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Sample records for neural sliding mode

  1. Adaptive Wavelet Neural Network Backstepping Sliding Mode Tracking Control for PMSM Drive System

    OpenAIRE

    Liu, Da; Li, Muguo

    2015-01-01

    This paper presents a wavelet neural network backstepping sliding mode controller (WNNBSSM) for permanent-magnet synchronous motor (PMSM) position servo control system. Backstepping sliding mode (BSSM) is utilized to guarantee favorable tracking performance and stability of the whole system, meanwhile, wavelet neural network (WNN) is used for approximating nonlinear uncertainties. The designed controller combined the merits of the backstepping sliding mode control with robust characteristics ...

  2. Adaptive Global Sliding Mode Control for MEMS Gyroscope Using RBF Neural Network

    Directory of Open Access Journals (Sweden)

    Yundi Chu

    2015-01-01

    Full Text Available An adaptive global sliding mode control (AGSMC using RBF neural network (RBFNN is proposed for the system identification and tracking control of micro-electro-mechanical system (MEMS gyroscope. Firstly, a new kind of adaptive identification method based on the global sliding mode controller is designed to update and estimate angular velocity and other system parameters of MEMS gyroscope online. Moreover, the output of adaptive neural network control is used to adjust the switch gain of sliding mode control dynamically to approach the upper bound of unknown disturbances. In this way, the switch item of sliding mode control can be converted to the output of continuous neural network which can weaken the chattering in the sliding mode control in contrast to the conventional fixed gain sliding mode control. Simulation results show that the designed control system can get satisfactory tracking performance and effective estimation of unknown parameters of MEMS gyroscope.

  3. Adaptive Sliding Mode Control of Chaos in Permanent Magnet Synchronous Motor via Fuzzy Neural Networks

    Directory of Open Access Journals (Sweden)

    Tat-Bao-Thien Nguyen

    2014-01-01

    Full Text Available In this paper, based on fuzzy neural networks, we develop an adaptive sliding mode controller for chaos suppression and tracking control in a chaotic permanent magnet synchronous motor (PMSM drive system. The proposed controller consists of two parts. The first is an adaptive sliding mode controller which employs a fuzzy neural network to estimate the unknown nonlinear models for constructing the sliding mode controller. The second is a compensational controller which adaptively compensates estimation errors. For stability analysis, the Lyapunov synthesis approach is used to ensure the stability of controlled systems. Finally, simulation results are provided to verify the validity and superiority of the proposed method.

  4. Adaptive Neural Network Sliding Mode Control for Quad Tilt Rotor Aircraft

    Directory of Open Access Journals (Sweden)

    Yanchao Yin

    2017-01-01

    Full Text Available A novel neural network sliding mode control based on multicommunity bidirectional drive collaborative search algorithm (M-CBDCS is proposed to design a flight controller for performing the attitude tracking control of a quad tilt rotors aircraft (QTRA. Firstly, the attitude dynamic model of the QTRA concerning propeller tension, channel arm, and moment of inertia is formulated, and the equivalent sliding mode control law is stated. Secondly, an adaptive control algorithm is presented to eliminate the approximation error, where a radial basis function (RBF neural network is used to online regulate the equivalent sliding mode control law, and the novel M-CBDCS algorithm is developed to uniformly update the unknown neural network weights and essential model parameters adaptively. The nonlinear approximation error is obtained and serves as a novel leakage term in the adaptations to guarantee the sliding surface convergence and eliminate the chattering phenomenon, which benefit the overall attitude control performance for QTRA. Finally, the appropriate comparisons among the novel adaptive neural network sliding mode control, the classical neural network sliding mode control, and the dynamic inverse PID control are examined, and comparative simulations are included to verify the efficacy of the proposed control method.

  5. Projective synchronization of nonidentical fractional-order neural networks based on sliding mode controller.

    Science.gov (United States)

    Ding, Zhixia; Shen, Yi

    2016-04-01

    This paper investigates global projective synchronization of nonidentical fractional-order neural networks (FNNs) based on sliding mode control technique. We firstly construct a fractional-order integral sliding surface. Then, according to the sliding mode control theory, we design a sliding mode controller to guarantee the occurrence of the sliding motion. Based on fractional Lyapunov direct methods, system trajectories are driven to the proposed sliding surface and remain on it evermore, and some novel criteria are obtained to realize global projective synchronization of nonidentical FNNs. As the special cases, some sufficient conditions are given to ensure projective synchronization of identical FNNs, complete synchronization of nonidentical FNNs and anti-synchronization of nonidentical FNNs. Finally, one numerical example is given to demonstrate the effectiveness of the obtained results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Minimal-Learning-Parameter Technique Based Adaptive Neural Sliding Mode Control of MEMS Gyroscope

    Directory of Open Access Journals (Sweden)

    Bin Xu

    2017-01-01

    Full Text Available This paper investigates an adaptive neural sliding mode controller for MEMS gyroscopes with minimal-learning-parameter technique. Considering the system uncertainty in dynamics, neural network is employed for approximation. Minimal-learning-parameter technique is constructed to decrease the number of update parameters, and in this way the computation burden is greatly reduced. Sliding mode control is designed to cancel the effect of time-varying disturbance. The closed-loop stability analysis is established via Lyapunov approach. Simulation results are presented to demonstrate the effectiveness of the method.

  7. Neural network-based sliding mode control for atmospheric-actuated spacecraft formation using switching strategy

    Science.gov (United States)

    Sun, Ran; Wang, Jihe; Zhang, Dexin; Shao, Xiaowei

    2018-02-01

    This paper presents an adaptive neural networks-based control method for spacecraft formation with coupled translational and rotational dynamics using only aerodynamic forces. It is assumed that each spacecraft is equipped with several large flat plates. A coupled orbit-attitude dynamic model is considered based on the specific configuration of atmospheric-based actuators. For this model, a neural network-based adaptive sliding mode controller is implemented, accounting for system uncertainties and external perturbations. To avoid invalidation of the neural networks destroying stability of the system, a switching control strategy is proposed which combines an adaptive neural networks controller dominating in its active region and an adaptive sliding mode controller outside the neural active region. An optimal process is developed to determine the control commands for the plates system. The stability of the closed-loop system is proved by a Lyapunov-based method. Comparative results through numerical simulations illustrate the effectiveness of executing attitude control while maintaining the relative motion, and higher control accuracy can be achieved by using the proposed neural-based switching control scheme than using only adaptive sliding mode controller.

  8. Adaptive Neural-Sliding Mode Control of Active Suspension System for Camera Stabilization

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2015-01-01

    Full Text Available The camera always suffers from image instability on the moving vehicle due to the unintentional vibrations caused by road roughness. This paper presents a novel adaptive neural network based on sliding mode control strategy to stabilize the image captured area of the camera. The purpose is to suppress vertical displacement of sprung mass with the application of active suspension system. Since the active suspension system has nonlinear and time varying characteristics, adaptive neural network (ANN is proposed to make the controller robustness against systematic uncertainties, which release the model-based requirement of the sliding model control, and the weighting matrix is adjusted online according to Lyapunov function. The control system consists of two loops. The outer loop is a position controller designed with sliding mode strategy, while the PID controller in the inner loop is to track the desired force. The closed loop stability and asymptotic convergence performance can be guaranteed on the basis of the Lyapunov stability theory. Finally, the simulation results show that the employed controller effectively suppresses the vibration of the camera and enhances the stabilization of the entire camera, where different excitations are considered to validate the system performance.

  9. RBF Neural Network of Sliding Mode Control for Time-Varying 2-DOF Parallel Manipulator System

    Directory of Open Access Journals (Sweden)

    Haizhong Chen

    2013-01-01

    Full Text Available This paper presents a radial basis function (RBF neural network control scheme for manipulators with actuator nonlinearities. The control scheme consists of a time-varying sliding mode control (TVSMC and an RBF neural network compensator. Since the actuator nonlinearities are usually included in the manipulator driving motor, a compensator using RBF network is proposed to estimate the actuator nonlinearities and their upper boundaries. Subsequently, an RBF neural network controller that requires neither the evaluation of off-line dynamical model nor the time-consuming training process is given. In addition, Barbalat Lemma is introduced to help prove the stability of the closed control system. Considering the SMC controller and the RBF network compensator as the whole control scheme, the closed-loop system is proved to be uniformly ultimately bounded. The whole scheme provides a general procedure to control the manipulators with actuator nonlinearities. Simulation results verify the effectiveness of the designed scheme and the theoretical discussion.

  10. Sliding Mode Control for NSVs with Input Constraint Using Neural Network and Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Yan-long Zhou

    2013-01-01

    Full Text Available The sliding mode control (SMC scheme is proposed for near space vehicles (NSVs with strong nonlinearity, high coupling, parameter uncertainty, and unknown time-varying disturbance based on radial basis function neural networks (RBFNNs and the nonlinear disturbance observer (NDO. Considering saturation characteristic of rudders, RBFNNs are constructed as a compensator to overcome the saturation nonlinearity. The stability of the closed-loop system is proved, and the tracking error as well as the disturbance observer error can converge to the origin through the Lyapunov analysis. Simulation results are presented to demonstrate the effectiveness of the proposed flight control scheme.

  11. Sliding Mode and Neural Network Control of Sensorless PMSM Controlled System for Power Consumption and Performance Improvement

    Directory of Open Access Journals (Sweden)

    Ming-Shyan Wang

    2017-11-01

    Full Text Available This paper deals with the design of sliding mode control and neural network compensation for a sensorless permanent magnet synchronous motor (PMSM controlled system that is able to improve both power consumption and speed response performance. The position sensor of PMSM is unreliable in harsh environments. Therefore, the sensorless control technique is widely proposed in industry. A sliding mode observer can estimate the rotor angle and has the robustness to load disturbance and parameter variations. However, the sliding mode observer is not conducive to standstill and low speed conditions because the amplitude of the back EMF is almost zero. As a result, this paper combines an iterative sliding mode observer (ISMO and neural networks (NNs as an angle compensator to improve the above problems. A dsPIC30F6010A-based PMSM sensorless drive system is implemented to validate the proposed algorithm. The simulation and experimental results prove its effectiveness.

  12. Robust fuzzy neural network sliding mode control scheme for IPMSM drives

    Science.gov (United States)

    Leu, V. Q.; Mwasilu, F.; Choi, H. H.; Lee, J.; Jung, J. W.

    2014-07-01

    This article proposes a robust fuzzy neural network sliding mode control (FNNSMC) law for interior permanent magnet synchronous motor (IPMSM) drives. The proposed control strategy not only guarantees accurate and fast command speed tracking but also it ensures the robustness to system uncertainties and sudden speed and load changes. The proposed speed controller encompasses three control terms: a decoupling control term which compensates for nonlinear coupling factors using nominal parameters, a fuzzy neural network (FNN) control term which approximates the ideal control components and a sliding mode control (SMC) term which is proposed to compensate for the errors of that approximation. Next, an online FNN training methodology, which is developed using the Lyapunov stability theorem and the gradient descent method, is proposed to enhance the learning capability of the FNN. Moreover, the maximum torque per ampere (MTPA) control is incorporated to maximise the torque generation in the constant torque region and increase the efficiency of the IPMSM drives. To verify the effectiveness of the proposed robust FNNSMC, simulations and experiments are performed by using MATLAB/Simulink platform and a TI TMS320F28335 DSP on a prototype IPMSM drive setup, respectively. Finally, the simulated and experimental results indicate that the proposed design scheme can achieve much better control performances (e.g. more rapid transient response and smaller steady-state error) when compared to the conventional SMC method, especially in the case that there exist system uncertainties.

  13. Equivalent Neural Network Optimal Coefficients Using Forgetting Factor with Sliding Modes

    Directory of Open Access Journals (Sweden)

    Karen Alicia Aguilar Cruz

    2016-01-01

    Full Text Available The Artificial Neural Network (ANN concept is familiar in methods whose task is, for example, the identification or approximation of the outputs of complex systems difficult to model. In general, the objective is to determine online the adequate parameters to reach a better point-to-point convergence rate, so that this paper presents the parameter estimation for an equivalent ANN (EANN, obtaining a recursive identification for a stochastic system, firstly, with constant parameters and, secondly, with nonstationary output system conditions. Therefore, in the last estimation, the parameters also have stochastic properties, making the traditional approximation methods not adequate due to their losing of convergence rate. In order to give a solution to this problematic, we propose a nonconstant exponential forgetting factor (NCEFF with sliding modes, obtaining in almost all points an exponential convergence rate decreasing. Theoretical results of both identification stages are performed using MATLAB® and compared, observing improvement when the new proposal for nonstationary output conditions is applied.

  14. Dynamic boundary layer based neural network quasi-sliding mode control for soft touching down on asteroid

    Science.gov (United States)

    Liu, Xiaosong; Shan, Zebiao; Li, Yuanchun

    2017-04-01

    Pinpoint landing is a critical step in some asteroid exploring missions. This paper is concerned with the descent trajectory control for soft touching down on a small irregularly-shaped asteroid. A dynamic boundary layer based neural network quasi-sliding mode control law is proposed to track a desired descending path. The asteroid's gravitational acceleration acting on the spacecraft is described by the polyhedron method. Considering the presence of input constraint and unmodeled acceleration, the dynamic equation of relative motion is presented first. The desired descending path is planned using cubic polynomial method, and a collision detection algorithm is designed. To perform trajectory tracking, a neural network sliding mode control law is given first, where the sliding mode control is used to ensure the convergence of system states. Two radial basis function neural networks (RBFNNs) are respectively used as an approximator for the unmodeled term and a compensator for the difference between the actual control input with magnitude constraint and nominal control. To improve the chattering induced by the traditional sliding mode control and guarantee the reachability of the system, a specific saturation function with dynamic boundary layer is proposed to replace the sign function in the preceding control law. Through the Lyapunov approach, the reachability condition of the control system is given. The improved control law can guarantee the system state move within a gradually shrinking quasi-sliding mode band. Numerical simulation results demonstrate the effectiveness of the proposed control strategy.

  15. Adaptive Sliding Mode Control of MEMS Gyroscope Based on Neural Network Approximation

    Directory of Open Access Journals (Sweden)

    Yuzheng Yang

    2014-01-01

    Full Text Available An adaptive sliding controller using radial basis function (RBF network to approximate the unknown system dynamics microelectromechanical systems (MEMS gyroscope sensor is proposed. Neural controller is proposed to approximate the unknown system model and sliding controller is employed to eliminate the approximation error and attenuate the model uncertainties and external disturbances. Online neural network (NN weight tuning algorithms, including correction terms, are designed based on Lyapunov stability theory, which can guarantee bounded tracking errors as well as bounded NN weights. The tracking error bound can be made arbitrarily small by increasing a certain feedback gain. Numerical simulation for a MEMS angular velocity sensor is investigated to verify the effectiveness of the proposed adaptive neural control scheme and demonstrate the satisfactory tracking performance and robustness.

  16. Sliding mode control and observation

    CERN Document Server

    Shtessel, Yuri; Fridman, Leonid; Levant, Arie

    2014-01-01

    The sliding mode control methodology has proven effective in dealing with complex dynamical systems affected by disturbances, uncertainties and unmodeled dynamics. Robust control technology based on this methodology has been applied to many real-world problems, especially in the areas of aerospace control, electric power systems, electromechanical systems, and robotics. Sliding Mode Control and Observation represents the first textbook that starts with classical sliding mode control techniques and progresses toward newly developed higher-order sliding mode control and observation algorithms and their applications. The present volume addresses a range of sliding mode control issues, including: *Conventional sliding mode controller and observer design *Second-order sliding mode controllers and differentiators *Frequency domain analysis of conventional and second-order sliding mode controllers *Higher-order sliding mode controllers and differentiators *Higher-order sliding mode observers *Sliding mode disturbanc...

  17. Sliding Mode Real-Time Control of Photovoltaic Systems Using Neural Estimators

    Directory of Open Access Journals (Sweden)

    J. A. Ramos-Hernanz

    2016-01-01

    Full Text Available The maximum power point tracking (MPPT problem has attracted the attention of many researchers, because it is convenient to obtain the maximum power of a photovoltaic module regardless of the weather conditions and the load. In this paper, a novel control for a boost DC/DC converter has been introduced. It is based on a sliding mode controller (SMC that takes a current signal as reference instead of a voltage, which is generated by a neuronal reference current generator. That reference current indicates the current (IMPP at the maximum power point (MPP for given weather conditions. In order to test the designed control system, a photovoltaic module model based on a second artificial neuronal network (ANN has been obtained from experimental data gathered during 18 months in the Faculty of Engineering Vitoria-Gasteiz (Spain. We have analyzed the performance of such model and we found that it is very accurate (MSE = 0.062 A and R = 0.991 with test dataset. We also have tested the performance of the overall SMC design with both simulated and real tests, concluding that it guarantees that the power in the output of the converter is very close to the power of the photovoltaic module output.

  18. Model-free adaptive sliding mode controller design for generalized projective synchronization of the fractional-order chaotic system via radial basis function neural networks

    Science.gov (United States)

    Wang, L. M.

    2017-09-01

    A novel model-free adaptive sliding mode strategy is proposed for a generalized projective synchronization (GPS) between two entirely unknown fractional-order chaotic systems subject to the external disturbances. To solve the difficulties from the little knowledge about the master-slave system and to overcome the bad effects of the external disturbances on the generalized projective synchronization, the radial basis function neural networks are used to approach the packaged unknown master system and the packaged unknown slave system (including the external disturbances). Consequently, based on the slide mode technology and the neural network theory, a model-free adaptive sliding mode controller is designed to guarantee asymptotic stability of the generalized projective synchronization error. The main contribution of this paper is that a control strategy is provided for the generalized projective synchronization between two entirely unknown fractional-order chaotic systems subject to the unknown external disturbances, and the proposed control strategy only requires that the master system has the same fractional orders as the slave system. Moreover, the proposed method allows us to achieve all kinds of generalized projective chaos synchronizations by turning the user-defined parameters onto the desired values. Simulation results show the effectiveness of the proposed method and the robustness of the controlled system.

  19. Mixed H∞ and passive projective synchronization for fractional-order memristor-based neural networks with time delays via adaptive sliding mode control

    Science.gov (United States)

    Song, Shuai; Song, Xiaona; Balsera, Ines Tejado

    2017-05-01

    This paper investigates the mixed H∞ and passive projective synchronization problem for fractional-order (FO) memristor-based neural networks with time delays. Our aim is to design a controller such that, though the unavoidable phenomena of time delay and external disturbances is fully considered, the resulting closed-loop system is stable with a mixed H∞ and passive performance level. By combining sliding mode control and adaptive control methods, a novel adaptive sliding mode control strategy is designed for the synchronization of time-delayed FO dynamic networks. Via the application of FO system stability theory, the projective synchronization conditions are addressed in terms of linear matrix inequalities. Based on the conditions, a desired controller which can guarantee the stability of the closed-loop system and also ensure a mixed H∞ and passive performance level is designed. Finally, two simulation examples are given to illustrate the effectiveness of the proposed method.

  20. Automobile Road Vibration Reproduction using Sliding Modes

    NARCIS (Netherlands)

    Monsees, G.; Scherpen, J.M.A.

    2001-01-01

    Sliding mode controllers have a reputation for their robustness against parameter variations, modeling errors and disturbances. They have been successfully applied in several practical situations which demonstrated the potential of sliding mode control for other control problems. However research

  1. An Adaptive B-Spline Neural Network and Its Application in Terminal Sliding Mode Control for a Mobile Satcom Antenna Inertially Stabilized Platform

    Science.gov (United States)

    Zhang, Xiaolei; Zhao, Yan; Guo, Kai; Li, Gaoliang; Deng, Nianmao

    2017-01-01

    The mobile satcom antenna (MSA) enables a moving vehicle to communicate with a geostationary Earth orbit satellite. To realize continuous communication, the MSA should be aligned with the satellite in both sight and polarization all the time. Because of coupling effects, unknown disturbances, sensor noises and unmodeled dynamics existing in the system, the control system should have a strong adaptability. The significant features of terminal sliding mode control method are robustness and finite time convergence, but the robustness is related to the large switching control gain which is determined by uncertain issues and can lead to chattering phenomena. Neural networks can reduce the chattering and approximate nonlinear issues. In this work, a novel B-spline curve-based B-spline neural network (BSNN) is developed. The improved BSNN has the capability of shape changing and self-adaption. In addition, the output of the proposed BSNN is applied to approximate the nonlinear function in the system. The results of simulations and experiments are also compared with those of PID method, non-singularity fast terminal sliding mode (NFTSM) control and radial basis function (RBF) neural network-based NFTSM. It is shown that the proposed method has the best performance, with reliable control precision. PMID:28452931

  2. An Adaptive B-Spline Neural Network and Its Application in Terminal Sliding Mode Control for a Mobile Satcom Antenna Inertially Stabilized Platform.

    Science.gov (United States)

    Zhang, Xiaolei; Zhao, Yan; Guo, Kai; Li, Gaoliang; Deng, Nianmao

    2017-04-28

    The mobile satcom antenna (MSA) enables a moving vehicle to communicate with a geostationary Earth orbit satellite. To realize continuous communication, the MSA should be aligned with the satellite in both sight and polarization all the time. Because of coupling effects, unknown disturbances, sensor noises and unmodeled dynamics existing in the system, the control system should have a strong adaptability. The significant features of terminal sliding mode control method are robustness and finite time convergence, but the robustness is related to the large switching control gain which is determined by uncertain issues and can lead to chattering phenomena. Neural networks can reduce the chattering and approximate nonlinear issues. In this work, a novel B-spline curve-based B-spline neural network (BSNN) is developed. The improved BSNN has the capability of shape changing and self-adaption. In addition, the output of the proposed BSNN is applied to approximate the nonlinear function in the system. The results of simulations and experiments are also compared with those of PID method, non-singularity fast terminal sliding mode (NFTSM) control and radial basis function (RBF) neural network-based NFTSM. It is shown that the proposed method has the best performance, with reliable control precision.

  3. Applications of sliding mode control

    CERN Document Server

    Ghommam, Jawhar; Zhu, Quanmin

    2017-01-01

    This book presents essential studies and applications in the context of sliding mode control, highlighting the latest findings from interdisciplinary theoretical studies, ranging from computational algorithm development to representative applications. Readers will learn how to easily tailor the techniques to accommodate their ad hoc applications. To make the content as accessible as possible, the book employs a clear route in each paper, moving from background to motivation, to quantitative development (equations), and lastly to case studies/illustrations/tutorials (simulations, experiences, curves, tables, etc.). Though primarily intended for graduate students, professors and researchers from related fields, the book will also benefit engineers and scientists from industry. .

  4. Using Sliding Modes in Control Theory

    Directory of Open Access Journals (Sweden)

    Renata Wagnerová

    2008-03-01

    Full Text Available The paper deals with sliding modes control design. The described control algorithms were applied to position control of the levitating systems in magnetic field. The designed control algorithms were verified by using computer simulations. The results achieved confirm suitable technical means and synthesis by using sliding modes for nonlinear control tasks.

  5. Sliding mode control for synchronous electric drives

    CERN Document Server

    Ryvkin, Sergey E

    2011-01-01

    This volume presents the theory of control systems with sliding mode applied to electrical motors and power converters. It demonstrates the methodology of control design and the original algorithms of control and observation. Practically all semiconductor devices are used in power converters, that feed electrical motors, as power switches. A switching mode offers myriad attractive, inherent properties from a control viewpoint, especially a sliding mode. Sliding mode control supplies high dynamics to systems, invariability of systems to changes of their parameters and of exterior loads in combi

  6. Model-free adaptive sliding mode controller design for generalized ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 89; Issue 3. Model-free adaptive sliding mode controller design for generalized projective synchronization of the fractional-order chaotic system via radial basis function neural networks. L M WANG. Research Article Volume 89 Issue 3 September 2017 Article ID 38 ...

  7. Accurate Sliding-Mode Control System Modeling for Buck Converters

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2007-01-01

    This paper shows that classical sliding mode theory fails to correctly predict the output impedance of the highly useful sliding mode PID compensated buck converter. The reason for this is identified as the assumption of the sliding variable being held at zero during sliding mode, effectively...... approach also predicts the self-oscillating switching action of the sliding-mode control system correctly. Analytical findings are verified by simulation as well as experimentally in a 10-30V/3A buck converter....

  8. Adaptive Sliding Mode Control for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper presents a new adaptive sliding mode controller generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The proposed control scheme requires limited knowledge on system parameters, and employs only piston- and valve spool position feedback...

  9. Applications of sliding mode control in science and engineering

    CERN Document Server

    Lien, Chang-Hua

    2017-01-01

    Gathering 20 chapters contributed by respected experts, this book reports on the latest advances in and applications of sliding mode control in science and engineering. The respective chapters address applications of sliding mode control in the broad areas of chaos theory, robotics, electrical engineering, physics, chemical engineering, memristors, mechanical engineering, environmental engineering, finance, and biology. Special emphasis has been given to papers that offer practical solutions, and which examine design and modeling involving new types of sliding mode control such as higher order sliding mode control, terminal sliding mode control, super-twisting sliding mode control, and integral sliding mode control. This book serves as a unique reference guide to sliding mode control and its recent applications for graduate students and researchers with a basic knowledge of electrical and control systems engineering.

  10. Sliding Mode Control of Induction Motor Phase Currents

    DEFF Research Database (Denmark)

    Hansen, R.B.; Hattel, T.; Bork, J

    1995-01-01

    Sliding mode control of induction motor phase currents are investigated through development of two control concepts.......Sliding mode control of induction motor phase currents are investigated through development of two control concepts....

  11. Position Control of PMSM in Sliding Mode

    Directory of Open Access Journals (Sweden)

    Peter Bris

    2008-01-01

    Full Text Available In the paper control of linear permanent magnet synchronous motor (PMSM based on the principles of sliding mode control (SMC with respect of vector control principles is carried out. The presented simulations comprise position quantization due to assumed experimental verification on the bench which consists of linear PMSM and incremental position sensor. Simulation results compare two methods for obtaining of position derivatives needed for SMC algorithm. The first method exploits a filtering observer and second one uses numerical derivations and first order filters.

  12. Robust Sliding Mode Control for Tokamaks

    Directory of Open Access Journals (Sweden)

    I. Garrido

    2012-01-01

    Full Text Available Nuclear fusion has arisen as an alternative energy to avoid carbon dioxide emissions, being the tokamak a promising nuclear fusion reactor that uses a magnetic field to confine plasma in the shape of a torus. However, different kinds of magnetohydrodynamic instabilities may affect tokamak plasma equilibrium, causing severe reduction of particle confinement and leading to plasma disruptions. In this sense, numerous efforts and resources have been devoted to seeking solutions for the different plasma control problems so as to avoid energy confinement time decrements in these devices. In particular, since the growth rate of the vertical instability increases with the internal inductance, lowering the internal inductance is a fundamental issue to address for the elongated plasmas employed within the advanced tokamaks currently under development. In this sense, this paper introduces a lumped parameter numerical model of the tokamak in order to design a novel robust sliding mode controller for the internal inductance using the transformer primary coil as actuator.

  13. Fuzzy sliding mode controller for doubly fed induction motor speed ...

    African Journals Online (AJOL)

    The results show that the FSMC and SMC are robust against internal and external perturbations, but the FSMC is superior to SMC in eliminating chattering phenomena and response time. Keywords: Direct Field-Oriented Control, sliding mode control, fuzzy sliding mode controller, doubly fed induction motor, fuzzy logic ...

  14. A novel fractional sliding mode control configuration for ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 89; Issue 3. A novel fractional sliding mode ... In this paper, a new design of fractional-order sliding mode control scheme is proposed for the synchronization of a class of nonlinear fractional-order systems with chaotic behaviour. The considered design approach ...

  15. Sliding mode control the delta-sigma modulation approach

    CERN Document Server

    Sira-Ramírez, Hebertt

    2015-01-01

    This monograph presents a novel method of sliding mode control for switch-regulated nonlinear systems. The Delta Sigma modulation approach allows one to implement a continuous control scheme using one or multiple, independent switches, thus effectively merging the available linear and nonlinear controller design techniques with sliding mode control.   Sliding Mode Control: The Delta-Sigma Modulation Approach, combines rigorous mathematical derivation of the unique features of Sliding Mode Control and Delta-Sigma modulation with numerous illustrative examples from diverse areas of engineering. In addition, engineering case studies demonstrate the applicability of the technique and the ease with which one can implement the exposed results. This book will appeal to researchers in control engineering and can be used as graduate-level textbook for a first course on sliding mode control.

  16. Active magnetic bearing system based on sliding mode control

    Science.gov (United States)

    Zhang, Yanhong

    2017-07-01

    A new sliding mode variable structure control algorithm suitable for active magnetic bearing is proposed, which is widely used for nonlinear control system. The model and controller is designed, simulation and experimental parts are also made, according to the switching function and the sliding mode control law. The current of electromagnet is adjusted to realize stable levitation of the rotor. The experimental result shows that the sliding mode variable structure controller is an effective way for magnetic bearing control, and the active magnetic bearing system is a highly nonlinear and advanced control method that can reduce the setting time and the cost.

  17. Application of fuzzy sliding-mode control in robot

    Science.gov (United States)

    Fu, Yongling; Wang, Yan

    2006-11-01

    The system of Pb-211 robot waist is a nonlinear hydraulic servo control system. It is very difficult to achieve speedy response without overshoot by the PID control algorithm for the system control. To improve the performance of the system, a new controller is designed with a fuzzy sliding-mode control algorithm, which makes use of the merits both the fuzzy control and the sliding-mode control algorithm. The simulation results show that the new controller is effective, which can achieve high speediness and steady accuracy without overshoot. The fuzzy sliding-mode control has obvious advantage compared the traditional PID algorithm, and it has strong robust too.

  18. Fuzzy Backstepping Sliding Mode Control for Mismatched Uncertain System

    Directory of Open Access Journals (Sweden)

    H. Q. Hou

    2014-06-01

    Full Text Available Sliding mode controllers have succeeded in many control problems that the conventional control theories have difficulties to deal with; however it is practically impossible to achieve high-speed switching control. Therefore, in this paper an adaptive fuzzy backstepping sliding mode control scheme is derived for mismatched uncertain systems. Firstly fuzzy sliding mode controller is designed using backstepping method based on the Lyapunov function approach, which is capable of handling mismatched problem. Then fuzzy sliding mode controller is designed using T-S fuzzy model method, it can improve the performance of the control systems and their robustness. Finally this method of control is applied to nonlinear system as a case study; simulation results are also provided the performance of the proposed controller.

  19. Discrete-time nonlinear sliding mode controller

    African Journals Online (AJOL)

    user

    transformation is defined to transform the time-delay and stability is proven for nonlinear sliding surface, which leads to show the asymptotic ... description of the discrete –time plant with state delay and its transformation, section III illustrates proposed design of nonlinear ...... Lee H.J., Jin Bae Park and Guanrong Chen, 2001.

  20. Sliding mode control on electro-mechanical systems

    Directory of Open Access Journals (Sweden)

    Utkin Vadim I.

    2002-01-01

    Full Text Available The first sliding mode control application may be found in the papers back in the 1930s in Russia. With its versatile yet simple design procedure the methodology is proven to be one of the most powerful solutions for many practical control designs. For the sake of demonstration this paper is oriented towards application aspects of sliding mode control methodology. First the design approach based on the regularization is generalized for mechanical systems. It is shown that stability of zero dynamics should be taken into account when the regular form consists of blocks of second-order equations. Majority of applications in the paper are related to control and estimation methods of automotive industry. New theoretical methods are developed in the context of these studies: sliding made nonlinear observers, observers with binary measurements, parameter estimation in systems with sliding mode control.

  1. Second order sliding mode control for a quadrotor UAV.

    Science.gov (United States)

    Zheng, En-Hui; Xiong, Jing-Jing; Luo, Ji-Liang

    2014-07-01

    A method based on second order sliding mode control (2-SMC) is proposed to design controllers for a small quadrotor UAV. For the switching sliding manifold design, the selection of the coefficients of the switching sliding manifold is in general a sophisticated issue because the coefficients are nonlinear. In this work, in order to perform the position and attitude tracking control of the quadrotor perfectly, the dynamical model of the quadrotor is divided into two subsystems, i.e., a fully actuated subsystem and an underactuated subsystem. For the former, a sliding manifold is defined by combining the position and velocity tracking errors of one state variable, i.e., the sliding manifold has two coefficients. For the latter, a sliding manifold is constructed via a linear combination of position and velocity tracking errors of two state variables, i.e., the sliding manifold has four coefficients. In order to further obtain the nonlinear coefficients of the sliding manifold, Hurwitz stability analysis is used to the solving process. In addition, the flight controllers are derived by using Lyapunov theory, which guarantees that all system state trajectories reach and stay on the sliding surfaces. Extensive simulation results are given to illustrate the effectiveness of the proposed control method. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Fuzzy Sliding Mode Control for Hyper Chaotic Chen System

    Directory of Open Access Journals (Sweden)

    SARAILOO, M.

    2012-02-01

    Full Text Available In this paper, a fuzzy sliding mode control method is proposed for stabilizing hyper chaotic Chen system. The main objective of the control scheme is to stabilize unstable equilibrium point of the system by controlling the states of the system so that they converge to a pre-defined sliding surface and remain on it. A fuzzy control technique is also utilized in order to overcome the main disadvantage of sliding mode control methods, i.e. chattering problem. It is shown that the equilibrium point of the system is stabilized by using the proposed method. A stability analysis is also performed to prove that the states of the system converge to the sliding surface and remain on it. Simulations show that the control method can be effectively applied to Chen system when it performs hyper chaotic behavior.

  3. Sliding mode controllers for a tempered glass furnace.

    Science.gov (United States)

    Almutairi, Naif B; Zribi, Mohamed

    2016-01-01

    This paper investigates the design of two sliding mode controllers (SMCs) applied to a tempered glass furnace system. The main objective of the proposed controllers is to regulate the glass plate temperature, the upper-wall temperature and the lower-wall temperature in the furnace to a common desired temperature. The first controller is a conventional sliding mode controller. The key step in the design of this controller is the introduction of a nonlinear transformation that maps the dynamic model of the tempered glass furnace into the generalized controller canonical form; this step facilitates the design of the sliding mode controller. The second controller is based on a state-dependent coefficient (SDC) factorization of the tempered glass furnace dynamic model. Using an SDC factorization, a simplified sliding mode controller is designed. The simulation results indicate that the two proposed control schemes work very well. Moreover, the robustness of the control schemes to changes in the system's parameters as well as to disturbances is investigated. In addition, a comparison of the proposed control schemes with a fuzzy PID controller is performed; the results show that the proposed SDC-based sliding mode controller gave better results. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  4. A generalized regular form for multivariable sliding mode control

    Directory of Open Access Journals (Sweden)

    W. Perruquetti

    2001-01-01

    Full Text Available The paper shows how to compute a diffeomorphic state space transformation in order to put the initial mutivariable nonlinear model into an appropriate regular form. This form is an extension of the one proposed by Lukyanov and Utkin [9], and constitutes a guidance for a “natural” choice of the sliding surface. Then stabilization is achieved via a sliding mode strategy. In order to overcome the chattering phenomenon, a new nonlinear gain is introduced.

  5. Sliding Mode Control for Trajectory Tracking of an Intelligent Wheelchair

    Directory of Open Access Journals (Sweden)

    Razvan SOLEA

    2009-12-01

    Full Text Available This paper deal with a robust sliding-mode trajectory tracking controller, fornonholonomic wheeled mobile robots and its experimental evaluation by theimplementation in an intelligent wheelchair (RobChair. The proposed control structureis based on two nonlinear sliding surfaces ensuring the tracking of the three outputvariables, with respect to the nonholonomic constraint. The performances of theproposed controller for the trajectory planning problem with comfort constraint areverified through the real time acceleration provided by an inertial measurement unit.

  6. Delamination of Composite Laminate Plate by Sliding Load Mode

    OpenAIRE

    Kormaníková Eva

    2017-01-01

    The paper presents the mixed-mode delamination response of laminate plate made of two sublaminates. To this purpose a sliding load mode of delamination is proposed as failure model. A quasistatic rate-independent delamination problem of laminate plates with a finite thickness is considered. A rate-independent delamination model for a laminated Kirchhoff-Love plate is obtained. The failure model is implemented in ANSYS code to calculate the mixed-mode delamination response as energy release ra...

  7. Sliding Mode Control (SMC) of Robot Manipulator via Intelligent Controllers

    Science.gov (United States)

    Kapoor, Neha; Ohri, Jyoti

    2017-02-01

    Inspite of so much research, key technical problem, naming chattering of conventional, simple and robust SMC is still a challenge to the researchers and hence limits its practical application. However, newly developed soft computing based techniques can provide solution. In order to have advantages of conventional and heuristic soft computing based control techniques, in this paper various commonly used intelligent techniques, neural network, fuzzy logic and adaptive neuro fuzzy inference system (ANFIS) have been combined with sliding mode controller (SMC). For validation, proposed hybrid control schemes have been implemented for tracking a predefined trajectory by robotic manipulator, incorporating structured and unstructured uncertainties in the system. After reviewing numerous papers, all the commonly occurring uncertainties like continuous disturbance, uniform random white noise, static friction like coulomb friction and viscous friction, dynamic friction like Dhal friction and LuGre friction have been inserted in the system. Various performance indices like norm of tracking error, chattering in control input, norm of input torque, disturbance rejection, chattering rejection have been used. Comparative results show that with almost eliminated chattering the intelligent SMC controllers are found to be more efficient over simple SMC. It has also been observed from results that ANFIS based controller has the best tracking performance with the reduced burden on the system. No paper in the literature has found to have all these structured and unstructured uncertainties together for motion control of robotic manipulator.

  8. Fuzzy-Sliding Mode Force Control Research on Robotic Machining

    Directory of Open Access Journals (Sweden)

    Shou-yan Chen

    2017-01-01

    Full Text Available The low stiffness has limited the applications of robot to machining process. In this paper, a fuzzy-sliding mode control scheme is proposed to manage the oscillation and chatter appearing in machining operation by adjusting the feed rate. The robotic machining dynamics is first analyzed to identify the parameters with focus on the system stiffness and the behavior during machining process. A controller consisting of a fuzzy estimation enginery which can determine the control gain coefficients according to system status and a sliding mode controller which is used to guarantee convergence and global stability of the system is then proposed. Simulations and experiments results show that, in comparison with open loop and fuzzy-PID control scheme, the fuzzy-sliding mode control scheme can reduce the amplitude and period of oscillation.

  9. Sliding mode tracking control for miniature unmanned helicopters

    Directory of Open Access Journals (Sweden)

    Bin Xian

    2015-02-01

    Full Text Available A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter’s dynamic model is divided into two subsystems, such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles’ dynamic effects and external disturbances. The global asymptotic stability (GAS of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportional-integral-derivative (PID and linear-quadratic regulator (LQR cascaded controller in the presence of wind gust disturbances.

  10. Optimal Sliding Mode Controllers for Attitude Stabilization of Flexible Spacecraft

    Directory of Open Access Journals (Sweden)

    Chutiphon Pukdeboon

    2011-01-01

    Full Text Available The robust optimal attitude control problem for a flexible spacecraft is considered. Two optimal sliding mode control laws that ensure the exponential convergence of the attitude control system are developed. Integral sliding mode control (ISMC is applied to combine the first-order sliding mode with optimal control and is used to control quaternion-based spacecraft attitude manoeuvres with external disturbances and an uncertainty inertia matrix. For the optimal control part the state-dependent Riccati equation (SDRE and optimal Lyapunov techniques are employed to solve the infinite-time nonlinear optimal control problem. The second method of Lyapunov is used to guarantee the stability of the attitude control system under the action of the proposed control laws. An example of multiaxial attitude manoeuvres is presented and simulation results are included to verify the usefulness of the developed controllers.

  11. A sliding mode controller for vehicular traffic flow

    Science.gov (United States)

    Li, Yongfu; Kang, Yuhao; Yang, Bin; Peeta, Srinivas; Zhang, Li; Zheng, Taixong; Li, Yinguo

    2016-11-01

    This study proposes a sliding mode controller for vehicular traffic flow based on a car-following model to enhance the smoothness and stability of traffic flow evolution. In particular, the full velocity difference (FVD) model is used to capture the characteristics of vehicular traffic flow. The proposed sliding mode controller is designed in terms of the error between the desired space headway and the actual space headway. The stability of the controller is guaranteed using the Lyapunov technique. Numerical experiments are used to compare the performance of sliding mode control (SMC) with that of feedback control. The results illustrate the effectiveness of the proposed SMC method in terms of the distribution smoothness and stability of the space headway, velocity, and acceleration profiles. They further illustrate that the SMC strategy is superior to that of the feedback control strategy, while enabling computational efficiency that can aid in practical applications.

  12. Cascade Control of Magnetic Levitation with Sliding Modes

    Directory of Open Access Journals (Sweden)

    Eroğlu Yakup

    2016-01-01

    Full Text Available The effectiveness and applicability of magnetic levitation systems need precise feedback control designs. A cascade control approach consisting of sliding mode control plus sliding mode control (SMC plus SMC is designed to solve position control problem and to provide a high control performance and robustness to the magnetic levitation plant. It is shown that the SMC plus SMC cascade controller is able to eliminate the effects of the inductance related uncertainties of the electromagnetic coil of the plant and achieve a robust and precise position control. Experimental and numerical results are provided to validate the effectiveness and feasibility of the method.

  13. Speed Control of Switched Reluctance Motor Using Fuzzy Sliding Mode

    Directory of Open Access Journals (Sweden)

    TAHOUR, A.

    2008-04-01

    Full Text Available In this paper, a fuzzy logic controller (FLC is designed, based on the similarity between the FLC and the sliding mode control (SMC, for a class of nonlinear system to tackle the nonlinear control problems with modelling uncertainties, plant parameters variations and external disturbances. The proposed scheme gives fast dynamic response with no overshoot and zero steady-state error. To show the validity and the effectiveness of the control method, simulations are performed for the speed control of a switched reluctance motor. The simulation results show that the controller designed is more effective than the conventional sliding mode controller in enhancing the robustness of control systems with high accuracy.

  14. Hierarchical Sliding Mode Algorithm for Athlete Robot Walking

    Directory of Open Access Journals (Sweden)

    Van Dong Hai Nguyen

    2017-01-01

    Full Text Available Dynamic equations and the control law for a class of robots with elastic underactuated MIMO system of legs, athlete Robot, are discussed in this paper. The dynamic equations are determined by Euler-Lagrange method. A new method based on hierarchical sliding mode for controlling postures is also introduced. Genetic algorithm is applied to design the oscillator for robot motion. Then, a hierarchical sliding mode controller is implemented to control basic posture of athlete robot stepping. Successful simulation results show the motion of athlete robot.

  15. Analysis of oversized sliding waveguide by mode matching and multi-mode network theory

    Energy Technology Data Exchange (ETDEWEB)

    Ohkubo, K.; Kubo, S.; Idei, H.; Shimozuma, T.; Yoshimura, Y.; Sato, M.; Takita, Y. [National Inst. for Fusion Science, Toki, Gifu (Japan); Leuterer, F. [Max-Planck Institut fuer Plasmaphysik, Garching (Germany)

    2000-12-01

    Transmission and reflection coefficients of HE{sub 11} hybrid modes in the sliding waveguide are discussed on the basis of mode matching method and multi-mode network theory. The sliding waveguide is composed of the corrugated waveguide with 88.9 mm{phi} and the smooth-wall waveguide with 110 mm{phi} in inner diameter. It is confirmed that the decrease in power of <0.2% at 84 GHz is obtained for 2 cm in gap of the sliding waveguide. At the sliding length near multi-half-wavelength in vacuum, transmission and reflection powers in the sliding waveguide change slightly, because the very small amount of standing wave of higher-order TE or TM modes is produced resonantly. (author)

  16. Sliding-Mode Control of PEM Fuel Cells

    CERN Document Server

    Kunusch, Cristian; Mayosky, Miguel

    2012-01-01

    Recent advances in catalysis technologies and new materials make fuel cells an economically appealing and clean energy source with massive market potential in portable devices, home power generation and the automotive industry. Among the more promising fuel-cell technologies are proton exchange membrane fuel cells (PEMFCs). Sliding-Mode Control of PEM Fuel Cells demonstrates the application of higher-order sliding-mode control to PEMFC dynamics. Fuel-cell dynamics are often highly nonlinear and the text shows the advantages of sliding modes in terms of robustness to external disturbance, modelling error and system-parametric disturbance using higher-order control to reduce chattering. Divided into two parts, the book first introduces the theory of fuel cells and sliding-mode control. It begins by contextualising PEMFCs both in terms of their development and within the hydrogen economy and today’s energy production situation as a whole. The reader is then guided through a discussion of fuel-cell operation pr...

  17. Model-free adaptive sliding mode controller design for generalized ...

    Indian Academy of Sciences (India)

    L M WANG

    2017-08-16

    Aug 16, 2017 ... Abstract. A novel model-free adaptive sliding mode strategy is proposed for a generalized projective synchronization (GPS) between two entirely unknown fractional-order chaotic systems subject to the external disturbances. To solve the difficulties from the little knowledge about the master–slave system ...

  18. Digital Sliding Mode Control of Anti-Lock Braking System

    Directory of Open Access Journals (Sweden)

    MITIC, D. B.

    2013-02-01

    Full Text Available The control of anti-lock braking system is a great challenge, because of the nonlinear and complex characteristics of braking dynamics, unknown parameters of vehicle environment and system parameter variations. Using some of robust control methods, such as sliding mode control, can be a right solution for these problems. In this paper, we introduce a novel approach to design of ABS controllers, which is based on digital sliding mode control with only input/output measurements. The relay term of the proposed digital sliding mode control is filtered through digital integrator, reducing the chattering phenomenon in that way, and the additional signal of estimated modelling error is introduced into control algorithm to enhance the system steady-state accuracy. The given solution was verified in real experimental framework and the obtained results were compared with the results of implementation of two other digital sliding mode control algorithms. It is shown that it gives better system response, higher steady-state accuracy and smaller chattering.

  19. Control of a Lightweight Flexible Robotic Arm Using Sliding Modes

    OpenAIRE

    Etxebarria, Victor; Sanz, Arantza; Lizarraga, Ibone

    2006-01-01

    This paper presents a robust control scheme for flexible link robotic manipulators, which is based on considering the flexible mechanical structure as a system with slow (rigid) and fast (flexible) modes that can be controlled separately. The rigid dynamics is controlled by means of a robust sliding-mode approach with well-established stability properties while an LQR optimal design is adopted for the flexible dynamics. Experimental results show that this composite approach achieves good clos...

  20. Adaptive Actor-Critic Design-Based Integral Sliding-Mode Control for Partially Unknown Nonlinear Systems With Input Disturbances.

    Science.gov (United States)

    Fan, Quan-Yong; Yang, Guang-Hong

    2016-01-01

    This paper is concerned with the problem of integral sliding-mode control for a class of nonlinear systems with input disturbances and unknown nonlinear terms through the adaptive actor-critic (AC) control method. The main objective is to design a sliding-mode control methodology based on the adaptive dynamic programming (ADP) method, so that the closed-loop system with time-varying disturbances is stable and the nearly optimal performance of the sliding-mode dynamics can be guaranteed. In the first step, a neural network (NN)-based observer and a disturbance observer are designed to approximate the unknown nonlinear terms and estimate the input disturbances, respectively. Based on the NN approximations and disturbance estimations, the discontinuous part of the sliding-mode control is constructed to eliminate the effect of the disturbances and attain the expected equivalent sliding-mode dynamics. Then, the ADP method with AC structure is presented to learn the optimal control for the sliding-mode dynamics online. Reconstructed tuning laws are developed to guarantee the stability of the sliding-mode dynamics and the convergence of the weights of critic and actor NNs. Finally, the simulation results are presented to illustrate the effectiveness of the proposed method.

  1. Delamination of Composite Laminate Plate by Sliding Load Mode

    Directory of Open Access Journals (Sweden)

    Kormaníková Eva

    2017-06-01

    Full Text Available The paper presents the mixed-mode delamination response of laminate plate made of two sublaminates. To this purpose a sliding load mode of delamination is proposed as failure model. A quasistatic rate-independent delamination problem of laminate plates with a finite thickness is considered. A rate-independent delamination model for a laminated Kirchhoff-Love plate is obtained. The failure model is implemented in ANSYS code to calculate the mixed-mode delamination response as energy release rate along the lamination front.

  2. Sliding Mode Attitude Control for Magnetic Actuated Satellite

    DEFF Research Database (Denmark)

    Wisniewski, Rafal

    1998-01-01

    control torques can only be generated perpendicular to the local geomagnetic field vector. This has been a serious obstacle for using magnetorquer based control for three-axis attitude control. This paper deals with three-axis stabilization of a low earth orbit satellite. The problem of controlling......Magnetic torquing is attractive as a control principle on small satellites. The actuation principle is to use the interaction between the earth's magnetic field and magnetic field generated by a coil set in the satellite. This control principle is inherently nonlinear, and difficult to use because...... the spacecraft attitude using only magnetic torquing is realized in the form of the sliding mode control. A three dimensional sliding manifold is proposed, and it is shown that the satellite motion on the sliding manifold is asymptotically stable...

  3. Anomaly Detection in Test Equipment via Sliding Mode Observers

    Science.gov (United States)

    Solano, Wanda M.; Drakunov, Sergey V.

    2012-01-01

    Nonlinear observers were originally developed based on the ideas of variable structure control, and for the purpose of detecting disturbances in complex systems. In this anomaly detection application, these observers were designed for estimating the distributed state of fluid flow in a pipe described by a class of advection equations. The observer algorithm uses collected data in a piping system to estimate the distributed system state (pressure and velocity along a pipe containing liquid gas propellant flow) using only boundary measurements. These estimates are then used to further estimate and localize possible anomalies such as leaks or foreign objects, and instrumentation metering problems such as incorrect flow meter orifice plate size. The observer algorithm has the following parts: a mathematical model of the fluid flow, observer control algorithm, and an anomaly identification algorithm. The main functional operation of the algorithm is in creating the sliding mode in the observer system implemented as software. Once the sliding mode starts in the system, the equivalent value of the discontinuous function in sliding mode can be obtained by filtering out the high-frequency chattering component. In control theory, "observers" are dynamic algorithms for the online estimation of the current state of a dynamic system by measurements of an output of the system. Classical linear observers can provide optimal estimates of a system state in case of uncertainty modeled by white noise. For nonlinear cases, the theory of nonlinear observers has been developed and its success is mainly due to the sliding mode approach. Using the mathematical theory of variable structure systems with sliding modes, the observer algorithm is designed in such a way that it steers the output of the model to the output of the system obtained via a variety of sensors, in spite of possible mismatches between the assumed model and actual system. The unique properties of sliding mode control

  4. Backstepping and sliding mode control hybridized for a prosthetic hand.

    Science.gov (United States)

    Engeberg, Erik D; Meek, Sanford G

    2009-02-01

    Open loop and force controllers are compared experimentally with three robust parallel force-velocity controllers that are developed for a prosthetic hand. Robust sliding mode, backstepping, and hybrid sliding mode-backstepping (HSMBS) parallel force-velocity controllers are tested by ten able-bodied subjects. Results obtained with a myoelectrically controlled prosthesis indicate that all three robust controllers offer a statistically significant improvement over linear hand prosthesis control schemes. The robust controllers enable the human operators to more easily manipulate a delicate object. Bench top experiments combined with quantitative and qualitative evaluations from ten test subjects reveal the HSMBS controller to be the best choice to improve control of powered prosthetic hands.

  5. Robust sliding-mode control of a MEMS optical switch

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi, Behrouz; Bahrami, Mohsen [Mechanical Engineering Department, Amirkabir University of Technology, 434 Hafez Ave., Tehran 15, Iran Aerospace Research Institute, Tehran (Iran, Islamic Republic of)

    2006-04-01

    Over the last few years interests have emerged for application of MEMS in telecommunications. The use of MEMS for optical switching has turned to be the most attractive since this application could revolutionize fiber optic telecommunications. In this paper a robust control strategy based on sliding-mode control theory is developed for a MEMS optical switch, considering electrical, mechanical, and optical models. Sliding-mode control enables compact realization of a robust controller tolerant of device characteristics variation, non-linearties, and types of inherent instabilities. Robustness of proposed control scheme against disturbances is proved by Lyapunov second method and demonstrated through simulations. In addition, the presented control scheme is simple to implement in practical application.

  6. Advances and applications in sliding mode control systems

    CERN Document Server

    Zhu, Quanmin

    2015-01-01

    This book describes the advances and applications in Sliding mode control (SMC) which is widely used as a powerful method to tackle uncertain nonlinear systems. The book is organized into 21 chapters which have been organised by the editors to reflect the various themes of sliding mode control. The book provides the reader with a broad range of material from first principles up to the current state of the art in the area of SMC and observation presented in a clear, matter-of-fact style. As such it is appropriate for graduate students with a basic knowledge of classical control theory and some knowledge of state-space methods and nonlinear systems. The resulting design procedures are emphasized using Matlab/Simulink software.    

  7. Design and Implementation of a Magnetic Levitation System Controller using Global Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Rudi Uswarman

    2014-07-01

    Full Text Available This paper presents global sliding mode control and conventional sliding mode control for stabilization position of a levitation object. Sliding mode control will be robusting when in sliding mode condition. However, it is not necessarily robust at attaining phase. In the global sliding mode control, the attaining motion phase was eliminated, so that the robustness of the controller can be improved. However, the value of the parameter uncertainties needs to be limited. Besides that, the common problem in sliding mode control is high chattering phenomenon. If the chattering is too large, it can make the system unstable due the limited ability of electronics component. The strategy to overcome the chattering phenomenon is needed. Based on simulation and experimental results, the global sliding mode control has better performance than conventional sliding mode control.  

  8. Recent advances in sliding modes from control to intelligent mechatronics

    CERN Document Server

    Efe, Mehmet

    2015-01-01

    This volume is dedicated to Professor Okyay Kaynak to commemorate his life time impactful research and scholarly achievements and outstanding services to profession. The 21 invited chapters have been written by leading researchers who, in the past, have had association with Professor Kaynak as either his students and associates or colleagues and collaborators. The focal theme of the volume is the Sliding Modes covering a broad scope of topics from theoretical investigations to their significant applications from Control to Intelligent Mechatronics.  

  9. Sliding mode control of a magnetic levitation system

    Directory of Open Access Journals (Sweden)

    Al-Muthairi N. F.

    2004-01-01

    Full Text Available Sliding mode control schemes of the static and dynamic types are proposed for the control of a magnetic levitation system. The proposed controllers guarantee the asymptotic regulation of the statesof the system to their desired values. Simulation results of the proposed controllers are given to illustrate the effectiveness of them. Robustness of the control schemes to changes in the parameters of the system is also investigated.

  10. A high performance switching audio amplifier using sliding mode control

    OpenAIRE

    Pillonnet, Gael; Cellier, Rémy; Abouchi, Nacer; Chiollaz, Monique

    2008-01-01

    International audience; The switching audio amplifiers are widely used in various portable and consumer electronics due to their high efficiency, but suffers from low audio performances due to inherent nonlinearity. This paper presents an integrated class D audio amplifier with low consumption and high audio performances. It includes a power stage and an efficient control based on sliding mode technique. This monolithic class D amplifier is capable of delivering up to 1W into 8Ω load at less ...

  11. Design of hybrid sliding mode controller based on fireworks algorithm for nonlinear inverted pendulum systems

    OpenAIRE

    Te-Jen Su; Shih-Ming Wang; Tsung-Ying Li; Sung-Tsun Shih; Van-Manh Hoang

    2016-01-01

    The objective of this article is to optimize parameters of a hybrid sliding mode controller based on fireworks algorithm for a nonlinear inverted pendulum system. The proposed controller is a combination of two modified types of the classical sliding mode controller, namely, baseline sliding mode controller and fast output sampling discrete sliding mode controller. The simulation process is carried out with MATLAB/Simulink. The results are compared with a published hybrid method using proport...

  12. Sliding Mode Disturbance Observer-Based Fractional Second-Order Nonsingular Terminal Sliding Mode Control for PMSM Position Regulation System

    Directory of Open Access Journals (Sweden)

    Hong-Ru Li

    2015-01-01

    Full Text Available This paper investigates the position regulation problem of permanent magnet synchronous motor (PMSM subject to parameter uncertainties and external disturbances. A novel fractional second-order nonsingular terminal sliding mode control (F2NTSMC is proposed and the finite time stability of the closed-loop system is ensured. A sliding mode disturbance observer (SMDO is developed to estimate and make feedforward compensation for the lumped disturbances of the PMSM system. Moreover, the finite-time convergence of estimation errors can be guaranteed. The control scheme combining F2NTSMC and SMDO can not only improve performance of the closed-loop system and attenuate disturbances, but also reduce chattering effectively. Simulation results show that the proposed control method can obtain satisfactory position tracking performance and strong robustness.

  13. Maximum Power Point Tracking Based on Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Nimrod Vázquez

    2015-01-01

    Full Text Available Solar panels, which have become a good choice, are used to generate and supply electricity in commercial and residential applications. This generated power starts with the solar cells, which have a complex relationship between solar irradiation, temperature, and output power. For this reason a tracking of the maximum power point is required. Traditionally, this has been made by considering just current and voltage conditions at the photovoltaic panel; however, temperature also influences the process. In this paper the voltage, current, and temperature in the PV system are considered to be a part of a sliding surface for the proposed maximum power point tracking; this means a sliding mode controller is applied. Obtained results gave a good dynamic response, as a difference from traditional schemes, which are only based on computational algorithms. A traditional algorithm based on MPPT was added in order to assure a low steady state error.

  14. Sliding mode controller design with fractional order differentiation: applications for unstable time delay systems

    OpenAIRE

    Yeroğlu, Celaleddin; Kavuran, Gürkan

    2015-01-01

    This paper presents a design method for a sliding mode controller with the contribution of a fractional order differential operator. The conventional sliding mode controller has been widely studied in different control applications. This paper proposes that the fractional order differential operator enlarges the output span of the classical sliding mode controller to obtain a better-fitting control signal for enhanced control performance. The sliding surface and the equivalent control ...

  15. Synchronization of Fractional-Order Chaotic Systems with Gaussian Fluctuation by Sliding Mode Control

    OpenAIRE

    Yong Xu; Hua Wang

    2013-01-01

    This paper is devoted to the problem of synchronization between fractional-order chaotic systems with Gaussian fluctuation by the method of fractional-order sliding mode control. A fractional integral (FI) sliding surface is proposed for synchronizing the uncertain fractional-order system, and then the sliding mode control technique is carried out to realize the synchronization of the given systems. One theorem about sliding mode controller is presented to prove the proposed controller can ma...

  16. Decentralized RBFNN Type-2 Fuzzy Sliding Mode Controller for Robot Manipulator Driven by Artificial Muscles

    Directory of Open Access Journals (Sweden)

    Rezoug Amar

    2012-11-01

    Full Text Available In the few last years, investigations in neural networks, fuzzy systems and their combinations become attractive research areas for modeling and controlling of uncertain systems. In this paper, we propose a new robust controller based on the integration of a Radial Base Function Neural Network (RBFNN and an Interval Type-2 Fuzzy Logic (IT2FLC for robot manipulator actuated by pneumatic artificial muscles (PAM. The proposed approach was synthesized for each joint using Sliding Mode Control (SMC and named Radial Base Function Neural Network Type-2 Fuzzy Sliding Mode Control (RBFT2FSMC. Several objectives can be accomplished using this control scheme such as: avoiding difficult modeling, attenuating the chattering effect of the SMC, reducing the rules number of the fuzzy control, guaranteeing the stability and the robustness of the system, and finally handling the uncertainties of the system. The proposed control approach is synthesized and the stability of the robot using this controller was analyzed using Lyapunov theory. In order to demonstrate the efficiency of the RBFT2FSMC compared to other control technique, simulations experiments were performed using linear model with parameters uncertainties obtained after identification stage. Results show the superiority of the proposed approach compared to RBFNN Type-1 Fuzzy SMC. Finally, an experimental study of the proposed approach was presented using 2-DOF robot.

  17. A sliding mode observer for hemodynamic characterization under modeling uncertainties

    KAUST Repository

    Zayane, Chadia

    2014-06-01

    This paper addresses the case of physiological states reconstruction in a small region of the brain under modeling uncertainties. The misunderstood coupling between the cerebral blood volume and the oxygen extraction fraction has lead to a partial knowledge of the so-called balloon model describing the hemodynamic behavior of the brain. To overcome this difficulty, a High Order Sliding Mode observer is applied to the balloon system, where the unknown coupling is considered as an internal perturbation. The effectiveness of the proposed method is illustrated through a set of synthetic data that mimic fMRI experiments.

  18. Observer Based Sliding Mode Attitude Control: Theoretical and Experimental Results

    Directory of Open Access Journals (Sweden)

    U. Jørgensen

    2011-07-01

    Full Text Available In this paper we present the design of a sliding mode controller for attitude control of spacecraft actuated by three orthogonal reaction wheels. The equilibrium of the closed loop system is proved to be asymptotically stable in the sense of Lyapunov. Due to cases where spacecraft do not have angular velocity measurements, an estimator for the generalized velocity is derived and asymptotic stability is proven for the observer. The approach is tested on an experimental platform with a sphere shaped Autonomous Underwater Vehicle SATellite: AUVSAT, developed at the Norwegian University of Science and Technology.

  19. Adaptive Fractional Fuzzy Sliding Mode Control for Multivariable Nonlinear Systems

    Directory of Open Access Journals (Sweden)

    Junhai Luo

    2014-01-01

    Full Text Available This paper presents a robust adaptive fuzzy sliding mode control method for a class of uncertain nonlinear systems. The fractional order calculus is employed in the parameter updating stage. The underlying stability analysis as well as parameter update law design is carried out by Lyapunov based technique. In the simulation, two examples including a comparison with the traditional integer order counterpart are given to show the effectiveness of the proposed method. The main contribution of this paper consists in the control performance is better for the fractional order updating law than that of traditional integer order.

  20. Robust dynamic sliding-mode control using adaptive RENN for magnetic levitation system.

    Science.gov (United States)

    Lin, Faa-Jeng; Chen, Syuan-Yi; Shyu, Kuo-Kai

    2009-06-01

    In this paper, a robust dynamic sliding mode control system (RDSMC) using a recurrent Elman neural network (RENN) is proposed to control the position of a levitated object of a magnetic levitation system considering the uncertainties. First, a dynamic model of the magnetic levitation system is derived. Then, a proportional-integral-derivative (PID)-type sliding-mode control system (SMC) is adopted for tracking of the reference trajectories. Moreover, a new PID-type dynamic sliding-mode control system (DSMC) is proposed to reduce the chattering phenomenon. However, due to the hardware being limited and the uncertainty bound being unknown of the switching function for the DSMC, an RDSMC is proposed to improve the control performance and further increase the robustness of the magnetic levitation system. In the RDSMC, an RENN estimator is used to estimate an unknown nonlinear function of lumped uncertainty online and replace the switching function in the hitting control of the DSMC directly. The adaptive learning algorithms that trained the parameters of the RENN online are derived using Lyapunov stability theorem. Furthermore, a robust compensator is proposed to confront the uncertainties including approximation error, optimal parameter vectors, and higher order terms in Taylor series. Finally, some experimental results of tracking the various periodic trajectories demonstrate the validity of the proposed RDSMC for practical applications.

  1. Control uncertain Genesio-Tesi chaotic system: Adaptive sliding mode approach

    Energy Technology Data Exchange (ETDEWEB)

    Dadras, Sara [Automation and Instruments Lab, Electrical Engineering Department, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)], E-mail: s_dadras@modares.ac.ir; Momeni, Hamid Reza [Automation and Instruments Lab, Electrical Engineering Department, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)], E-mail: momeni_h@modares.ac.ir

    2009-12-15

    An adaptive sliding mode control (ASMC) technique is introduced in this paper for a chaotic dynamical system (Genesio-Tesi system). Using the sliding mode control technique, a sliding surface is determined and the control law is established. An adaptive sliding mode control law is derived to make the states of the Genesio-Tesi system asymptotically track and regulate the desired state. The designed control scheme can control the uncertain chaotic behaviors to a desired state without oscillating very fast and guarantee the property of asymptotical stability. An illustrative simulation result is given to demonstrate the effectiveness of the proposed adaptive sliding mode control design.

  2. Adaptive Sliding Mode Control of MEMS AC Voltage Reference Source

    Directory of Open Access Journals (Sweden)

    Ehsan Ranjbar

    2017-01-01

    Full Text Available The accuracy of physical parameters of a tunable MEMS capacitor, as the major part of MEMS AC voltage reference, is of great importance to achieve an accurate output voltage free of the malfunctioning noise and disturbance. Even though strenuous endeavors are made to fabricate MEMS tunable capacitors with desiderated accurate physical characteristics and ameliorate exactness of physical parameters’ values, parametric uncertainties ineluctably emerge in fabrication process attributable to imperfections in micromachining process. First off, this paper considers applying an adaptive sliding mode controller design in the MEMS AC voltage reference source so that it is capable of giving off a well-regulated output voltage in defiance of jumbling parametric uncertainties in the plant dynamics and also aggravating external disturbance imposed on the system. Secondly, it puts an investigatory comparison with the designed model reference adaptive controller and the pole-placement state feedback one into one’s prospective. Not only does the tuned adaptive sliding mode controller show remarkable robustness against slow parameter variation and external disturbance being compared to the pole-placement state feedback one, but also it immensely gets robust against the external disturbance in comparison with the conventional adaptive controller. The simulation results are promising.

  3. Adaptive sliding mode formation control of multiple underwater robots

    Directory of Open Access Journals (Sweden)

    Das Bikramaditya

    2014-12-01

    Full Text Available This paper proposes a new adaptive sliding mode control scheme for achieving coordinated motion control of a group of autonomous underwater vehicles with variable added mass. The control law considers the communication constraints in the acoustic medium. A common reference frame for velocity is assigned to a virtual leader dynamically. The performances of the proposed adaptive SMC were compared with that of a passivity based controller. To save the time and traveling distance for reaching the FRP by the follower AUVs, a sliding mode controller is proposed in this paper that drives the state trajectory of the AUV into a switching surface in the state space. It is observed from the obtained results that the proposed SMC provides improved performance in terms of accurately tracking the desired trajectory within less time compared to the passivity based controller. A communication consensus is designed ensuring the transfer of information among the AUVs so that they move collectively as a group. The stability of the overall closed-loop systems are analysed using Lyapunov theory and simulation results confirmed the robustness and efficiency of proposed controller.

  4. PID Controller of Sprayer Chassis by Sliding Mode

    Directory of Open Access Journals (Sweden)

    Hua Zhang

    2017-01-01

    Full Text Available In order to solve the straight line drive coordinated control problem of the four-wheel independent drive sprayer chassis, the dynamic model of sprayer chassis and electromagnetic proportional valve controlled hydraulic motor model are established. The additional yaw moment is designed to rectify the deviation with sliding mode variable structure control. PID control strategy is used to calculate the control voltage adjustment of the electromagnetic proportional valve. The simulation results show that the accumulative deviation of the chassis is 0.2 m out of 100 m when the coordinated control strategy is adopted on different adhesive coefficient pavement, which is much smaller than the value without control. The test results of test prototype show that the yaw acceleration of the chassis can be as low as −0.0132 m/s2 on different adhesive coefficient pavement with coordinated control, which is smaller than the value without control, and the straight line drive requirements are met. It is feasible to combine sliding mode variable structure with PID control and use the electromagnetic proportional control technology in the straight line drive coordinated control of sprayer chassis by adding the yaw moment to rectify the deviation of chassis based on the yaw acceleration detection.

  5. Enhanced adaptive fuzzy sliding mode control for uncertain nonlinear systems

    Science.gov (United States)

    Roopaei, Mehdi; Zolghadri, Mansoor; Meshksar, Sina

    2009-09-01

    In this article, a novel Adaptive Fuzzy Sliding Mode Control (AFSMC) methodology is proposed based on the integration of Sliding Mode Control (SMC) and Adaptive Fuzzy Control (AFC). Making use of the SMC design framework, we propose two fuzzy systems to be used as reaching and equivalent parts of the SMC. In this way, we make use of the fuzzy logic to handle uncertainty/disturbance in the design of the equivalent part and provide a chattering free control for the design of the reaching part. To construct the equivalent control law, an adaptive fuzzy inference engine is used to approximate the unknown parts of the system. To get rid of the chattering, a fuzzy logic model is assigned for reaching control law, which acting like the saturation function technique. The main advantage of our proposed methodology is that the structure of the system is unknown and no knowledge of the bounds of parameters, uncertainties and external disturbance are required in advance. Using Lyapunov stability theory and Barbalat's lemma, the closed-loop system is proved to be stable and convergence properties of the system is assured. Simulation examples are presented to verify the effectiveness of the method. Results are compared with some other methods proposed in the past research.

  6. Adaptive suboptimal second-order sliding mode control for microgrids

    Science.gov (United States)

    Incremona, Gian Paolo; Cucuzzella, Michele; Ferrara, Antonella

    2016-09-01

    This paper deals with the design of adaptive suboptimal second-order sliding mode (ASSOSM) control laws for grid-connected microgrids. Due to the presence of the inverter, of unpredicted load changes, of switching among different renewable energy sources, and of electrical parameters variations, the microgrid model is usually affected by uncertain terms which are bounded, but with unknown upper bounds. To theoretically frame the control problem, the class of second-order systems in Brunovsky canonical form, characterised by the presence of matched uncertain terms with unknown bounds, is first considered. Four adaptive strategies are designed, analysed and compared to select the most effective ones to be applied to the microgrid case study. In the first two strategies, the control amplitude is continuously adjusted, so as to arrive at dominating the effect of the uncertainty on the controlled system. When a suitable control amplitude is attained, the origin of the state space of the auxiliary system becomes attractive. In the other two strategies, a suitable blend between two components, one mainly working during the reaching phase, the other being the predominant one in a vicinity of the sliding manifold, is generated, so as to reduce the control amplitude in steady state. The microgrid system in a grid-connected operation mode, controlled via the selected ASSOSM control strategies, exhibits appreciable stability properties, as proved theoretically and shown in simulation.

  7. Sliding mode predictive guidance for terminal rendezvous in eccentric orbits

    Science.gov (United States)

    Kasaeian, Seyed Aliakbar; Assadian, Nima; Ebrahimi, Masoud

    2017-11-01

    This paper presents a robust guidance algorithm for a chaser spacecraft to rendezvous with a target spacecraft in Earth orbit. The basis of the proposed guidance method is finding an appropriate set of states as close as possible to the current states that would lead the spacecraft to the target in the desired mission time. In order to provide the prediction of states, the relative dynamics equations of motion are solved analytically for the chaser spacecraft rendezvous considering constant acceleration. Although the equations are solved for rendezvous with circular orbit target, it is shown by several simulations that the proposed guidance algorithm is applicable in perturbed elliptical orbits rendezvous as well. The sliding mode method as a robust nonlinear method is utilized as the steering law. The robust steering law tracks the desired states computed by the predictive guidance method. The Lyapunov stability method proves the asymptotic stability of the integrated guidance and steering laws. Because the proposed closed-loop guidance is simple and computationally easy, it is suitable for implementation in real-time applications. Some numerical simulations are conducted to show the performance of the proposed guidance method in different conditions. It is illustrated that compared with other steering laws, the fuel consumption is reduced utilizing the proposed guidance approach. The results reveal that the sliding mode guarantees the tracking of the required states and minimum final errors even in the presence of uncertainties and disturbances.

  8. Sliding Mode Control Strategy for Wind Turbine Power Maximization

    Directory of Open Access Journals (Sweden)

    Oscar Barambones

    2012-07-01

    Full Text Available The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, a sliding mode control for variable speed wind turbine that incorporates a doubly fed induction generator is described. The electrical system incorporates a wound rotor induction machine with back-to-back three phase power converter bridges between its rotor and the grid. In the presented design the so-called vector control theory is applied, in order to simplify the electrical equations. The proposed control scheme uses stator flux-oriented vector control for the rotor side converter bridge control and grid voltage vector control for the grid side converter bridge control. The stability analysis of the proposed sliding mode controller under disturbances and parameter uncertainties is provided using the Lyapunov stability theory. Finally simulated results show, on the one hand, that the proposed controller provides high-performance dynamic characteristics, and on the other hand, that this scheme is robust with respect to the uncertainties that usually appear in the real systems.

  9. High-Order Sliding Mode Control for DFIG-Based Wind Turbine Fault Ride-Through

    OpenAIRE

    Benbouzid, Mohamed; Beltran, Brice; Amirat, Yassine; Gang, Yao; Jingang, Han; Mangel, Hervé

    2013-01-01

    International audience; This paper deals with the Fault Ride-Through (FRT) capability assessment of a Doubly-Fed Induction Generator (DFIG)-based Wind Turbine (WT) using High-Order Sliding Mode (HOSM) control. Indeed, it has been recently suggested that sliding mode control is a solution of choice to the FRT problem. In this context, this paper proposes HOSM as an improved solution that handle the classical sliding mode chattering problem. Indeed, the main and attractive features of HOSMs are...

  10. Sensorless sliding mode torque control of an IPMSM drive based on active flux concept

    OpenAIRE

    Hassan, A.A.; El-Sawy, A.M.; Mohamed, Y.S.; Shehata, E.G.

    2012-01-01

    This paper investigates a novel direct torque control of a sensorless interior permanent magnet synchronous motor based on a sliding mode technique. The speed and position of the interior permanent magnet synchronous motor are estimated online based on active flux concept. To overcome the large ripple content associated with the direct torque, a torque/flux sliding mode controller has been employed. Two integral surface functions are used to construct the sliding mode controller. The command ...

  11. Hierarchical sliding mode control for under-actuated cranes design, analysis and simulation

    CERN Document Server

    Qian, Dianwei

    2015-01-01

    This book reports on the latest developments in sliding mode overhead crane control, presenting novel research ideas and findings on sliding mode control (SMC), hierarchical SMC and compensator design-based hierarchical sliding mode. The results, which were previously scattered across various journals and conference proceedings, are now presented in a systematic and unified form. The book will be of interest to researchers, engineers and graduate students in control engineering and mechanical engineering who want to learn the methods and applications of SMC.

  12. Fault tolerant control schemes using integral sliding modes

    CERN Document Server

    Hamayun, Mirza Tariq; Alwi, Halim

    2016-01-01

    The key attribute of a Fault Tolerant Control (FTC) system is its ability to maintain overall system stability and acceptable performance in the face of faults and failures within the feedback system. In this book Integral Sliding Mode (ISM) Control Allocation (CA) schemes for FTC are described, which have the potential to maintain close to nominal fault-free performance (for the entire system response), in the face of actuator faults and even complete failures of certain actuators. Broadly an ISM controller based around a model of the plant with the aim of creating a nonlinear fault tolerant feedback controller whose closed-loop performance is established during the design process. The second approach involves retro-fitting an ISM scheme to an existing feedback controller to introduce fault tolerance. This may be advantageous from an industrial perspective, because fault tolerance can be introduced without changing the existing control loops. A high fidelity benchmark model of a large transport aircraft is u...

  13. Adaptive and Robust Sliding Mode Position Control of IPMSM Drives

    Directory of Open Access Journals (Sweden)

    ZAKY, M.

    2017-02-01

    Full Text Available This paper proposes an adaptive and robust sliding mode control (SMC for the position control of Interior Permanent Magnet Synchronous Motor (IPMSM drives. A switching surface of SMC is designed using a Linear Quadratic Regulator (LQR technique to simultaneously control the tracking trajectory and load torque changes. The quadratic optimal control method is used to select the state feedback control gain that constitutes the system dynamic performance under uncertainties and disturbances. Feedback and switching gains are selected to satisfy both stability and fast convergence of the IPMSM. Matlab/Simulink is used to build the drive system. Experimental implementation of the IPMSM drive is carried out using DSP-DS1102 control board. The efficacy of the proposed position control method is validated using theoretical analysis and simulation and experimental results.

  14. Design of hybrid sliding mode controller based on fireworks algorithm for nonlinear inverted pendulum systems

    Directory of Open Access Journals (Sweden)

    Te-Jen Su

    2016-12-01

    Full Text Available The objective of this article is to optimize parameters of a hybrid sliding mode controller based on fireworks algorithm for a nonlinear inverted pendulum system. The proposed controller is a combination of two modified types of the classical sliding mode controller, namely, baseline sliding mode controller and fast output sampling discrete sliding mode controller. The simulation process is carried out with MATLAB/Simulink. The results are compared with a published hybrid method using proportional–integral–derivative and linear quadratic regulator controllers. The simulation results show a better performance of the proposed controller.

  15. Robust Control of a Hydraulically Actuated Manipulator Using Sliding Mode Control

    DEFF Research Database (Denmark)

    Hansen, Michael Rygaard; Andersen, Torben Ole; Pedersen, Henrik Clemmensen

    2005-01-01

    This paper presents an approach to robust control called sliding mode control (SMC) applied to the a hydraulic servo system (HSS), consisting of a servo valve controlled symmetrical cylinder. The motivation for applying sliding mode control to hydraulically actuated systems is its robustness...... towards structured (parametric) and unstructured (unmodeled dynamics) uncertainties. A third-order model of the actuated system is used to develop a sliding mode control which is implemented and tested on a simulation model. To avoid measurement of velocity and acceleration a simple first-order model...... is furthermore used to develop a simple sliding mode control (SSMC). The performance of the two controllers are compared and discussed....

  16. A Sliding Mode Control of Semi-Active Suspension Systems with Describing Function Method

    Science.gov (United States)

    Toyama, Shigehiro; Ikeda, Fujio

    This paper presents a sliding mode controller of semi-active suspension systems. The sliding mode controller is designed by the describing function method so that a switching function is enforced into a desired limit cycle instead of a perfect sliding mode. Although the proposed sliding mode controller cannot generate the limit cycle as desired because of the passive constraint of controllable dampers, restricting the switching function in the vicinity of the origin can suppress the deterioration due to the passive constraint, such as increase of jerk of the sprung mass. Finally, simulation results show the effectiveness of the proposed controller.

  17. Design and Simulation of Sliding Mode Fuzzy Controller for Nonlinear System

    Directory of Open Access Journals (Sweden)

    Ahmed Khalaf Hamoudi

    2016-03-01

    Full Text Available Sliding Mode Controller (SMC is a simple method and powerful technique to design a robust controller for nonlinear systems. It is an effective tool with acceptable performance. The major drawback is a classical Sliding Mode controller suffers from the chattering phenomenon which causes undesirable zigzag motion along the sliding surface. To overcome the snag of this classical approach, many methods were proposed and implemented. In this work, a Fuzzy controller was added to classical Sliding Mode controller in order to reduce the impact chattering problem. The new structure is called Sliding Mode Fuzzy controller (SMFC which will also improve the properties and performance of the classical Sliding Mode controller. A single inverted pendulum has been utilized for testing the design of the proposed controller. Programming and Simulink by Matlab have been used for the simulation results.

  18. Vehicle Hybrid Braking Control Using Sliding Mode Control

    Science.gov (United States)

    Kasahara, Misawa; Kanai, Yuki; Shiraki, Ryoko; Mori, Yasuchika

    Anti-lock brake system and brake-by-wire are proposed in the vehicle control using a brake, and the braking power is expected to be improved more than ever. The researches such as an application to the ABS of Siliding mode control which considered a actuator dynamics and a hybrid control of the brake using model reference adaptive control are done so far. However, in the former case, speed following that becomes a target exists physically impossible situation by saturation of tire frictional force because only speed following is done. In the latter, the model error is caused because the simulation model and the controller design model are different. Therefore, there is a problem that an accurate follow cannot be done. In this paper, the braking control is performed using the sliding mode control which has high robustness for disturbance that fulfils matching conditions. In so doing, it aims at the achievement of optimal braking control to switch wheel speed following to slip ratio following.

  19. Robust Sliding Mode Control Based on GA Optimization and CMAC Compensation for Lower Limb Exoskeleton

    Directory of Open Access Journals (Sweden)

    Yi Long

    2016-01-01

    Full Text Available A lower limb assistive exoskeleton is designed to help operators walk or carry payloads. The exoskeleton is required to shadow human motion intent accurately and compliantly to prevent incoordination. If the user’s intention is estimated accurately, a precise position control strategy will improve collaboration between the user and the exoskeleton. In this paper, a hybrid position control scheme, combining sliding mode control (SMC with a cerebellar model articulation controller (CMAC neural network, is proposed to control the exoskeleton to react appropriately to human motion intent. A genetic algorithm (GA is utilized to determine the optimal sliding surface and the sliding control law to improve performance of SMC. The proposed control strategy (SMC_GA_CMAC is compared with three other types of approaches, that is, conventional SMC without optimization, optimal SMC with GA (SMC_GA, and SMC with CMAC compensation (SMC_CMAC, all of which are employed to track the desired joint angular position which is deduced from Clinical Gait Analysis (CGA data. Position tracking performance is investigated with cosimulation using ADAMS and MATLAB/SIMULINK in two cases, of which the first case is without disturbances while the second case is with a bounded disturbance. The cosimulation results show the effectiveness of the proposed control strategy which can be employed in similar exoskeleton systems.

  20. Robust Sliding Mode Control Based on GA Optimization and CMAC Compensation for Lower Limb Exoskeleton.

    Science.gov (United States)

    Long, Yi; Du, Zhi-Jiang; Wang, Wei-Dong; Dong, Wei

    2016-01-01

    A lower limb assistive exoskeleton is designed to help operators walk or carry payloads. The exoskeleton is required to shadow human motion intent accurately and compliantly to prevent incoordination. If the user's intention is estimated accurately, a precise position control strategy will improve collaboration between the user and the exoskeleton. In this paper, a hybrid position control scheme, combining sliding mode control (SMC) with a cerebellar model articulation controller (CMAC) neural network, is proposed to control the exoskeleton to react appropriately to human motion intent. A genetic algorithm (GA) is utilized to determine the optimal sliding surface and the sliding control law to improve performance of SMC. The proposed control strategy (SMC_GA_CMAC) is compared with three other types of approaches, that is, conventional SMC without optimization, optimal SMC with GA (SMC_GA), and SMC with CMAC compensation (SMC_CMAC), all of which are employed to track the desired joint angular position which is deduced from Clinical Gait Analysis (CGA) data. Position tracking performance is investigated with cosimulation using ADAMS and MATLAB/SIMULINK in two cases, of which the first case is without disturbances while the second case is with a bounded disturbance. The cosimulation results show the effectiveness of the proposed control strategy which can be employed in similar exoskeleton systems.

  1. A Novel Control Approach Based on Second Order Sliding Modes & Its Application to Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    Sliding modes impose strong robustness toward parametric plant uncertainties and disturbances and accurate tracking performance in control systems. However, in physical systems the application of sliding modes may give rise to undesirable chattering of the control signal due to actuator dynamics....... chattering. Simulation studies confirm the announced properties when applied to a hydraulic drive model subjected to strong variations in supply pressure and friction....

  2. Adaptive Switching Gain for a Discrete-Time Sliding Mode Controller

    NARCIS (Netherlands)

    Monsees, G.; Scherpen, J.M.A.

    2000-01-01

    Sliding Mode Control is a well-known technique capable of making the closed loop system robust with respect to certain kinds of parameter variations and unmodeled dynamics. The sliding mode control law consists of the linear control part which is based on the model knowledge and the discontinuous

  3. An adaptive sliding mode backstepping control for the mobile manipulator with nonholonomic constraints

    Science.gov (United States)

    Chen, Naijian; Song, Fangzhen; Li, Guoping; Sun, Xuan; Ai, Changsheng

    2013-10-01

    To solve disturbances, nonlinearity, nonholonomic constraints and dynamic coupling between the platform and its mounted robot manipulator, an adaptive sliding mode controller based on the backstepping method applied to the robust trajectory tracking of the wheeled mobile manipulator is described in this article. The control algorithm rests on adopting the backstepping method to improve the global ultimate asymptotic stability and applying the sliding mode control to obtain high response and invariability to uncertainties. According to the Lyapunov stability criterion, the wheeled mobile manipulator is divided into several stabilizing subsystems, and an adaptive law is designed to estimate the general nondeterminacy, which make the controller be capable to drive the trajectory tracking error of the mobile manipulator to converge to zero even in the presence of perturbations and mathematical model errors. We compare our controller with the robust neural network based algorithm in nonholonomic constraints and uncertainties, and simulation results prove the effectivity and feasibility of the proposed method in the trajectory tracking of the wheeled mobile manipulator.

  4. Longitudinal Motion Control of AUV Based on Fuzzy Sliding Mode Method

    Directory of Open Access Journals (Sweden)

    Duo Qi

    2016-01-01

    Full Text Available According to the characteristics of AUV movement, a fuzzy sliding mode controller was designed, in which fuzzy rules were adopted to estimate the switching gain to eliminate disturbance terms and reduce chattering. The six-degree-of-freedom model of AUV was simplified and longitudinal motion equations were established on the basis of previous research. The influences of first-order wave force and torque were taken into consideration. The REMUS was selected to simulate the control effects of conventional sliding mode controller and fuzzy sliding mode controller. Simulation results show that the fuzzy sliding mode controller can meet the requirements and has higher precision and stronger antijamming performances compared with conventional sliding mode controller.

  5. A Robust Control Concept for Hydraulic Drives Based on Second Order Sliding Mode Disturbance Compensation

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben O.; Johansen, Per

    2017-01-01

    The application of sliding mode algorithms for control of hydraulic drives has gained increasing interest in recent years due to algorithm simplicity, low number of parameters and possible excellent control performance. Both application of firstand higher order sliding mode control algorithms...... chattering, which on the other hand compromises the robustness properties. This may also be the case when discontinuities are only present in the control derivative. This fact suggests that sliding mode algorithms may be more appropriate for assisting the control, i.e. for state observation, disturbance...... observer based control etc., and several examples of such approaches have been presented in literature. The latter case appear especially interesting as a sliding mode actually takes place, but only the low-pass filtered sliding mode algorithm output is used in the actual control input. However...

  6. Nonsingular Terminal Sliding Mode Control of Uncertain Second-Order Nonlinear Systems

    Directory of Open Access Journals (Sweden)

    Minh-Duc Tran

    2015-01-01

    Full Text Available This paper presents a high-performance nonsingular terminal sliding mode control method for uncertain second-order nonlinear systems. First, a nonsingular terminal sliding mode surface is introduced to eliminate the singularity problem that exists in conventional terminal sliding mode control. By using this method, the system not only can guarantee that the tracking errors reach the reference value in a finite time with high-precision tracking performance but also can overcome the complex-value and the restrictions of the exponent (the exponent should be fractional number with an odd numerator and an odd denominator in traditional terminal sliding mode. Then, in order to eliminate the chattering phenomenon, a super-twisting higher-order nonsingular terminal sliding mode control method is proposed. The stability of the closed-loop system is established using the Lyapunov theory. Finally, simulation results are presented to illustrate the effectiveness of the proposed method.

  7. Kinect-Based Sliding Mode Control for Lynxmotion Robotic Arm

    Directory of Open Access Journals (Sweden)

    Ismail Ben Abdallah

    2016-01-01

    Full Text Available Recently, the technological development of manipulator robot increases very quickly and provides a positive impact to human life. The implementation of the manipulator robot technology offers more efficiency and high performance for several human’s tasks. In reality, efforts published in this context are focused on implementing control algorithms with already preprogrammed desired trajectories (passive robots case or trajectory generation based on feedback sensors (active robots case. However, gesture based control robot can be considered as another channel of system control which is not widely discussed. This paper focuses on a Kinect-based real-time interactive control system implementation. Based on LabVIEW integrated development environment (IDE, a developed human-machine-interface (HMI allows user to control in real time a Lynxmotion robotic arm. The Kinect software development kit (SDK provides a tool to keep track of human body skeleton and abstract it into 3-dimensional coordinates. Therefore, the Kinect sensor is integrated into our control system to detect the different user joints coordinates. The Lynxmotion dynamic has been implemented in a real-time sliding mode control algorithm. The experimental results are carried out to test the effectiveness of the system, and the results verify the tracking ability, stability, and robustness.

  8. PSO based neuro fuzzy sliding mode control for a robot manipulator

    Directory of Open Access Journals (Sweden)

    M. Vijay

    2017-05-01

    Full Text Available This paper presents the control strategy of two degrees of freedom (2DOF rigid robot manipulator based on the coupling of artificial neuro fuzzy inference system (ANFIS with sliding mode control (SMC. Initially SMC with proportional integral derivative (PID sliding surface is adapted to control the robot manipulator. The parameters of the sliding surface are obtained by minimizing a quadratic performance indices using particle swarm optimization (PSO. Variations of SMC i.e. boundary sliding mode control (BSMC and boundary sliding mode control with PID sliding surface (PIDBSMC are developed for optimized performance index. Finally an ANFIS adaptive controller is proposed to generate the adaptive control signal and found to be more robust with regard to disturbances in input torque.

  9. Fractional-Order Fast Terminal Sliding Mode Control for a Class of Dynamical Systems

    Directory of Open Access Journals (Sweden)

    Guoliang Zhao

    2013-01-01

    Full Text Available This paper introduces a novel fractional fast terminal sliding mode control strategy for a class of dynamical systems with uncertainty. In this strategy, a fractional-order sliding surface is proposed, the corresponding control law is derived based on Lyapunov stability theory to guarantee the sliding condition, and the finite time stability of the closeloop system is also ensured. Further, to achieve the equivalence between convergence rate and singularity avoidance, a fractional-order nonsingular fast terminal sliding mode controller is studied and the stability is presented. Finally, numerical simulation results are presented to illustrate the effectiveness of the proposed method.

  10. Designing for Damage: Robust Flight Control Design using Sliding Mode Techniques

    Science.gov (United States)

    Vetter, T. K.; Wells, S. R.; Hess, Ronald A.; Bacon, Barton (Technical Monitor); Davidson, John (Technical Monitor)

    2002-01-01

    A brief review of sliding model control is undertaken, with particular emphasis upon the effects of neglected parasitic dynamics. Sliding model control design is interpreted in the frequency domain. The inclusion of asymptotic observers and control 'hedging' is shown to reduce the effects of neglected parasitic dynamics. An investigation into the application of observer-based sliding mode control to the robust longitudinal control of a highly unstable is described. The sliding mode controller is shown to exhibit stability and performance robustness superior to that of a classical loop-shaped design when significant changes in vehicle and actuator dynamics are employed to model airframe damage.

  11. Design and analysis of adaptive Super-Twisting sliding mode control for a microgyroscope

    Science.gov (United States)

    Feng, Zhilin

    2018-01-01

    This paper proposes a novel adaptive Super-Twisting sliding mode control for a microgyroscope under unknown model uncertainties and external disturbances. In order to improve the convergence rate of reaching the sliding surface and the accuracy of regulating and trajectory tracking, a high order Super-Twisting sliding mode control strategy is employed, which not only can combine the advantages of the traditional sliding mode control with the Super-Twisting sliding mode control, but also guarantee that the designed control system can reach the sliding surface and equilibrium point in a shorter finite time from any initial state and avoid chattering problems. In consideration of unknown parameters of micro gyroscope system, an adaptive algorithm based on Lyapunov stability theory is designed to estimate the unknown parameters and angular velocity of microgyroscope. Finally, the effectiveness of the proposed scheme is demonstrated by simulation results. The comparative study between adaptive Super-Twisting sliding mode control and conventional sliding mode control demonstrate the superiority of the proposed method. PMID:29298297

  12. Active Disturbance Rejection Approach for Robust Fault-Tolerant Control via Observer Assisted Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    John Cortés-Romero

    2013-01-01

    Full Text Available This work proposes an active disturbance rejection approach for the establishment of a sliding mode control strategy in fault-tolerant operations. The core of the proposed active disturbance rejection assistance is a Generalized Proportional Integral (GPI observer which is in charge of the active estimation of lumped nonlinear endogenous and exogenous disturbance inputs related to the creation of local sliding regimes with limited control authority. Possibilities are explored for the GPI observer assisted sliding mode control in fault-tolerant schemes. Convincing improvements are presented with respect to classical sliding mode control strategies. As a collateral advantage, the observer-based control architecture offers the possibility of chattering reduction given that a significant part of the control signal is of the continuous type. The case study considers a classical DC motor control affected by actuator faults, parametric failures, and perturbations. Experimental results and comparisons with other established sliding mode controller design methodologies, which validate the proposed approach, are provided.

  13. Sequence-dependent nucleosome sliding in rotation-coupled and uncoupled modes revealed by molecular simulations.

    Science.gov (United States)

    Niina, Toru; Brandani, Giovanni B; Tan, Cheng; Takada, Shoji

    2017-12-01

    While nucleosome positioning on eukaryotic genome play important roles for genetic regulation, molecular mechanisms of nucleosome positioning and sliding along DNA are not well understood. Here we investigated thermally-activated spontaneous nucleosome sliding mechanisms developing and applying a coarse-grained molecular simulation method that incorporates both long-range electrostatic and short-range hydrogen-bond interactions between histone octamer and DNA. The simulations revealed two distinct sliding modes depending on the nucleosomal DNA sequence. A uniform DNA sequence showed frequent sliding with one base pair step in a rotation-coupled manner, akin to screw-like motions. On the contrary, a strong positioning sequence, the so-called 601 sequence, exhibits rare, abrupt transitions of five and ten base pair steps without rotation. Moreover, we evaluated the importance of hydrogen bond interactions on the sliding mode, finding that strong and weak bonds favor respectively the rotation-coupled and -uncoupled sliding movements.

  14. Sliding Window Empirical Mode Decomposition -its performance and quality

    Directory of Open Access Journals (Sweden)

    Stepien Pawel

    2014-12-01

    Proposed algorithm speeds up (about 10 times the computation with acceptable quality of decomposition. Conclusions Sliding Window EMD algorithm is suitable for decomposition of long signals with high sampling frequency.

  15. Sliding Mode Control of Dynamic Voltage Restorer by Using a New Adaptive Reaching Law

    Science.gov (United States)

    Pandey, Achala; Agrawal, Rekha; Mandloi, Ravindra S.; Sarkar, Biswaroop

    2017-08-01

    This paper presents a new kind of adaptive reaching law for sliding mode control of Dynamic Voltage Restorer (DVR). Such an adaptive reaching law follows under-damped sinusoidal nature that causes the initial state to reach the sliding regime in extremely less time with negligible chattering. Moreover, it is robust in the sense the trajectory does not deviate from the sliding surface. This new approach is developed and successfully applied to DVR. The simulation results are presented that show its robustness.

  16. Research on Synthetic Aperture Radar Processing for the Spaceborne Sliding Spotlight Mode.

    Science.gov (United States)

    Shen, Shijian; Nie, Xin; Zhang, Xinggan

    2018-02-03

    Gaofen-3 (GF-3) is China' first C-band multi-polarization synthetic aperture radar (SAR) satellite, which also provides the sliding spotlight mode for the first time. Sliding-spotlight mode is a novel mode to realize imaging with not only high resolution, but also wide swath. Several key technologies for sliding spotlight mode in spaceborne SAR with high resolution are investigated in this paper, mainly including the imaging parameters, the methods of velocity estimation and ambiguity elimination, and the imaging algorithms. Based on the chosen Convolution BackProjection (CBP) and PFA (Polar Format Algorithm) imaging algorithms, a fast implementation method of CBP and a modified PFA method suitable for sliding spotlight mode are proposed, and the processing flows are derived in detail. Finally, the algorithms are validated by simulations and measured data.

  17. Nonlinear disturbance observer based sliding mode control of a cable-driven rehabilitation robot.

    Science.gov (United States)

    Niu, Jie; Yang, Qianqian; Chen, Guangtao; Song, Rong

    2017-07-01

    This paper introduces a cable-driven robot for upper-limb rehabilitation. Kinematic and dynamic of this rehabilitation robot is analyzed. A sliding mode controller combined with a nonlinear disturbance observer is proposed to control this robot in the presence of disturbances. Simulation is carried out to prove the effectiveness of the proposed control scheme, and the results of the proposed controller is compared with a PID controller and a traditional sliding mode controller. Results show that the proposed controller can effectively improve the tracking performance as compared with the other two controllers and cause lower chattering as compared with a traditional sliding mode controller.

  18. Stabilization and tracking control of X-Z inverted pendulum with sliding-mode control.

    Science.gov (United States)

    Wang, Jia-Jun

    2012-11-01

    X-Z inverted pendulum is a new kind of inverted pendulum which can move with the combination of the vertical and horizontal forces. Through a new transformation, the X-Z inverted pendulum is decomposed into three simple models. Based on the simple models, sliding-mode control is applied to stabilization and tracking control of the inverted pendulum. The performance of the sliding mode control is compared with that of the PID control. Simulation results show that the design scheme of sliding-mode control is effective for the stabilization and tracking control of the X-Z inverted pendulum. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Application of Sensorless Sliding Mode Observer in Control of Induction Motor Drive

    Directory of Open Access Journals (Sweden)

    Chau Si Thien Dong

    2017-01-01

    Full Text Available Induction motors are widely used in an industry and it is necessary to improve control methods for induction motors to increase the efficiency of them. In this paper, sliding mode controllers are proposed instead of traditional PI controllers in vector control of induction motor drives. Moreover, rotor speed is estimated by a sliding mode observer. In addition, the robustness of control and observer algorithms are also proved by Lyapunov’s criterion. The experiments are obtained in different speed changes of an induction motor drive. These experimental results confirm the dynamic properties of a sensorless sliding mode control of an induction motor drive.

  20. Sliding mode pulse-width modulation technique for direct torque controlled induction motor drive

    Science.gov (United States)

    Bounadja, M.; Belarbi, A. W.; Belmadani, B.

    2010-05-01

    This paper presents a novel pulse-width modulation technique based sliding mode approach for direct torque control of an induction machine drive. Methodology begins with a sliding mode control of machine's torque and stator flux to generate the reference voltage vector and to reduce parameters sensitivity. Then, the switching control of the three-phase inverter is developed using sliding mode concept to make the system tracking reference voltage inputs. The main features of the proposed methodologies are the high tracking accuracy and the much easier implementation compared to the space vector modulation. Simulations are carried out to confirm the effectiveness of proposed control algorithms.

  1. The novel sliding mode speed control based on interior permanent magnet synchronous motor

    Science.gov (United States)

    Liu, Jiaxi; Li, Lili; Du, Pengcheng

    2013-01-01

    In order to overcome the effect of the nonlinear load and uncertain motor parameters of PMSM in high performance servo system, a high-order terminal sliding mode control method is proposed for the speed loop design. The sliding mode controller is stable with Lyapunov theory and the adaptive of sliding mode gain is obtained. This approach improves the robustness of system and steady response and eliminates the chattering phenomenon. The simulation and experiment system is built to prove the correctness of this method.

  2. Sliding-mode adaptive control of Pioneer 3-DX wheeled mobile robot

    Directory of Open Access Journals (Sweden)

    Adrian FILIPESCU

    2007-12-01

    Full Text Available Parameter identification scheme and discrete-time adaptive sliding-mode controller applied to Pioneer 3-DX wheeled mobile robot (WMR are presented in this paper. The dynamical model for mobile robot with one pair of active wheels, time–varying mass and moment of inertia have been used in sliding-mode control. Two closed-loop, on-line parameter estimators have been used in order to achieve robustness against parameter uncertainties (robot mass and moment of inertia. Two sliding-mode adaptive controllers corresponding to angular and position motion have been designed. Closed-loop circular trajectory tracking Pioneer 3-DX real-time control is presented.

  3. Tensor Product Model Transformation Based Adaptive Integral-Sliding Mode Controller: Equivalent Control Method

    Directory of Open Access Journals (Sweden)

    Guoliang Zhao

    2013-01-01

    Full Text Available This paper proposes new methodologies for the design of adaptive integral-sliding mode control. A tensor product model transformation based adaptive integral-sliding mode control law with respect to uncertainties and perturbations is studied, while upper bounds on the perturbations and uncertainties are assumed to be unknown. The advantage of proposed controllers consists in having a dynamical adaptive control gain to establish a sliding mode right at the beginning of the process. Gain dynamics ensure a reasonable adaptive gain with respect to the uncertainties. Finally, efficacy of the proposed controller is verified by simulations on an uncertain nonlinear system model.

  4. Nonlinear torque and air-to-fuel ratio control of spark ignition engines using neuro-sliding mode techniques.

    Science.gov (United States)

    Huang, Ting; Javaherian, Hossein; Liu, Derong

    2011-06-01

    This paper presents a new approach for the calibration and control of spark ignition engines using a combination of neural networks and sliding mode control technique. Two parallel neural networks are utilized to realize a neuro-sliding mode control (NSLMC) for self-learning control of automotive engines. The equivalent control and the corrective control terms are the outputs of the neural networks. Instead of using error backpropagation algorithm, the network weights of equivalent control are updated using the Levenberg-Marquardt algorithm. Moreover, a new approach is utilized to update the gain of corrective control. Both modifications of the NSLMC are aimed at improving the transient performance and speed of convergence. Using the data from a test vehicle with a V8 engine, we built neural network models for the engine torque (TRQ) and the air-to-fuel ratio (AFR) dynamics and developed NSLMC controllers to achieve tracking control. The goal of TRQ control and AFR control is to track the commanded values under various operating conditions. From simulation studies, the feasibility and efficiency of the approach are illustrated. For both control problems, excellent tracking performance has been achieved.

  5. On Application of Second Order Sliding Mode Control to Electro-Hydraulic Systems

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2014-01-01

    This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive implementa......This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive...... implementation of sliding mode control, achieving continuous control inputs, while maintaining the main properties of sliding modes. Under certain model assumptions, some of these controllers may even be applied as output feedback controllers. However, intrinsic nonlinear dynamic effects of hydraulic valves...... sliding algorithm known as the super twisting controller is considered for output feedback control and compared with conventional first order sliding mode control. The controllers under consideration are applied for position tracking control of a hydraulic valve-cylinder drive exhibiting strong variations...

  6. Switched Reluctance Generator Output Voltage Ripple Reduction Based on Fuzzy Sliding Mode

    Directory of Open Access Journals (Sweden)

    Xia Fei

    2015-01-01

    Full Text Available Aiming at the problem of Switched Reluctance Generator output voltage ripple, this paper designs a fuzzy sliding mode controller based on the analysis of various factors affecting the output voltage ripple. The traditional sliding mode controller has quick convergence, but it has chattering problem. This paper introduces the fuzzy control to select the appropriate sliding mode gain. It can combine with traditional angle control to adjust the output voltage by adjusting the conduction angle. It is more effective in shortening the adjustment time and reducing the overshoot and steady-state of error compared with the classical PID control. Meanwhile, it also solves the chattering problem of traditional sliding mode control. Finally, it makes use of nonlinear model structure to validate that it is effective in restraining voltage ripple and improving the dynamic performance of the system and the voltage quality.

  7. Health Parameter Estimation with Second-Order Sliding Mode Observer for a Turbofan Engine

    National Research Council Canada - National Science Library

    Xiaodong Chang; Jinquan Huang; Feng Lu

    2017-01-01

    In this paper the problem of health parameter estimation in an aero-engine is investigated by using an unknown input observer-based methodology, implemented by a second-order sliding mode observer (SOSMO...

  8. Robust Sliding Mode Control of Permanent Magnet Synchronous Generator-Based Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Guangping Zhuo

    2016-12-01

    Full Text Available The subject of this paper pertains to sliding mode control and its application in nonlinear electrical power systems as seen in wind energy conversion systems. Due to the robustness in dealing with unmodeled system dynamics, sliding mode control has been widely used in electrical power system applications. This paper presents first and high order sliding mode control schemes for permanent magnet synchronous generator-based wind energy conversion systems. The application of these methods for control using dynamic models of the d-axis and q-axis currents, as well as those of the high speed shaft rotational speed show a high level of efficiency in power extraction from a varying wind resource. Computer simulation results have shown the efficacy of the proposed sliding mode control approaches.

  9. Finite time control for MIMO nonlinear system based on higher-order sliding mode.

    Science.gov (United States)

    Liu, Xiangjie; Han, Yaozhen

    2014-11-01

    Considering a class of MIMO uncertain nonlinear system, a novel finite time stable control algorithm is proposed based on higher-order sliding mode concept. The higher-order sliding mode control problem of MIMO nonlinear system is firstly transformed into finite time stability problem of multivariable system. Then continuous control law, which can guarantee finite time stabilization of nominal integral chain system, is employed. The second-order sliding mode is used to overcome the system uncertainties. High frequency chattering phenomenon of sliding mode is greatly weakened, and the arbitrarily fast convergence is reached. The finite time stability is proved based on the quadratic form Lyapunov function. Examples concerning the triple integral chain system with uncertainty and the hovercraft trajectory tracking are simulated respectively to verify the effectiveness and the robustness of the proposed algorithm. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Analysis and Sliding Mode Control of Four-Wire Three-Leg Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Farid Hamoudi

    2015-01-01

    Full Text Available In this paper, the analysis and the sliding mode control application for a shunt active filter is presented. The active filter is based on a three-leg split-capacitor voltage source inverter which is used to compensate harmonics and unbalance in the phase currents, and therefore to cancel neutral current. The proposed sliding mode control is formulated from the multivariable state model established in dq0 frames. The selection of the sliding mode functions takes in account simultaneously, the current tracking and the dc-bus regulation and balancing, without the need of outer loops for the dc-bus control. A particular attention is given to the sliding mode functions design in order to optimize the convergence of the zero-sequence error and the dc-bus voltage unbalance. The effectiveness of the proposed control has been verified through computer simulation where satisfactory results are obtained over different conditions.

  11. Discrete Sliding Mode Control for Hypersonic Cruise Missile

    Directory of Open Access Journals (Sweden)

    Yong Hua Fan

    2016-01-01

    Full Text Available A discrete variable structure control (DVSC with sliding vector is presented to track the velocity and acceleration command for a hypersonic cruise missile. In the design an integrator is augmented to ensure the tracking with zero steady-state errors. Furthermore the sliding surface of acceleration is designed using the error of acceleration and acceleration rate to avoid the singularity of control matrix. A proper power rate reaching law is utilized in this proposal; therefore the state trajectory from any initial point can be driven into the sliding surface. Besides, in order to validate the robustness of controller, the unmolded dynamic and parameter disturbance of the missile are considered. Through simulation the proposed controller demonstrates good performance in tracking velocity and acceleration command.

  12. The simplex method for nonlinear sliding mode control

    Directory of Open Access Journals (Sweden)

    Bartolini G.

    1998-01-01

    Full Text Available General nonlinear control systems described by ordinary differential equations with a prescribed sliding manifold are considered. A method of designing a feedback control law such that the state variable fulfills the sliding condition in finite time is based on the construction of a suitable simplex of vectors in the tangent space of the manifold. The convergence of the method is proved under an obtuse angle condition and a way to build the required simplex is indicated. An example of engineering interest is presented.

  13. Sliding Mode Strategy for PEM Fuel Cells Stacks Breathing Control Using a Super-Twisting Algorithm

    OpenAIRE

    Kunusch, Cristian; Puleston, Pablo Federico; Mayosky, Miguel Ángel; Riera, Jordi

    2009-01-01

    A second-order sliding mode strategy to control the breathing subsystem of a polymer electrolyte membrane fuel cell stack for transportation applications is presented. The controller is developed from a design model of the plant derived from open literature, and well suited for the design of second-order sliding mode strategies. Stability issues are solved using a super twisting algorithm. The resulting approach exhibits good dynamic characteristics, being robust to uncertainties and disturba...

  14. Simulation and Research of Control-System for PMSM Based on Sliding Mode Control

    Science.gov (United States)

    Baofeng, Lv; Guoxiang, Zhang

    In this paper, permanent magnet synchronous motor rotor flux oriented control strategy is studied, for the key issues of vector control is to observe the rotor flux, the control system is given based on sliding mode observer, and the sliding mode rotor flux observer is designed, with MATLAB/SIMULINK simulation, the results of simulation show that the system with wide speed range, has a good dynamic and static performance.

  15. Second Order Sliding Mode Control with Prescribed Convergence Law for Electro-Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper discusses the application of second order sliding modes for position tracking control of electro-hydraulic valve-cylinder drives (VCD’s). The target is to introduce increased tracking- and transient performance compared to conventional linear approaches, without extending the number...... approach, and that control chattering is eliminated without introducing a boundary layer, normally seen in first order sliding mode controlled systems....

  16. Sliding Mode Control of the Fractional-Order Unified Chaotic System

    Directory of Open Access Journals (Sweden)

    Jian Yuan

    2013-01-01

    Full Text Available This paper deals with robust synchronization of the fractional-order unified chaotic systems. Firstly, control design for synchronization of nominal systems is proposed via fractional sliding mode technique. Then, systematic uncertainties and external disturbances are considered in the fractional-order unified chaotic systems, and adaptive sliding mode control is designed for the synchronization issue. Finally, numerical simulations are carried out to verify the effectiveness of the two proposed control techniques.

  17. On sliding mode control design for UAV using realistic aerodynamic coefficients

    OpenAIRE

    Perozzi, Gabriele; Efimov, Denis; Biannic, Jean-Marc; Planckaert, Laurent; Coton, Patricia

    2017-01-01

    International audience; The goal of this paper is to design a control of mini quadrotor under wind perturbations. Taking into account a detailed unmanned aerial vehicle (UAV) model, the aim is to find a sliding mode control law minimizing the impact of the wind field on UAV dynamics. For this purpose an aerodynamic modelization of external disturbance is introduced. After that, upper bounds of these disturbances are computed. Lastly, the sliding mode altitude and attitude controls are designe...

  18. Low-cost sliding mode control of WECS based on DFIG with stability analysis

    OpenAIRE

    DJOUDI, ABDELHAK; CHEKIREB, Hachemi; BERKOUK, EL MADJID; Bacha, Seddik

    2015-01-01

    The aim of this work is to developing sliding mode control of active and reactive stator powers produced by a wind energy conversion system (WECS), based on doubly fed induction generator (DFIG). A flux estimation model and rotor current sensor are no longer required. The controller is developed from the DFIG nonlinear-coupled model. Moreover, the global stability and the DFIG states' boundedness when our low-cost sliding mode control is applied are established analytically. It is re...

  19. Robust excitation control design using sliding-mode technique for multimachine power systems

    Energy Technology Data Exchange (ETDEWEB)

    Colbia-Vega, A.; de Leon-Morales, J.; Salas-Pena, O.; Mata-Jimenez, M.T. [Mechanical and Electrical Engineering Faculty, Autonomous University of Nuevo Leon, Cd. Universitaria, 66450 San Nicolas de los Garza, N.L. (Mexico); Fridman, L. [Department of Control, Division of Electrical Engineering Faculty, National Autonomous University of Mexico, Cd. Universitaria, 04510 Mexico, D.F. (Mexico)

    2008-09-15

    An output feedback controller is proposed to enhance the transient stability of nonlinear multimachine power systems considered as a classical model with flux decay dynamics. Combining high-order sliding-mode techniques with a robust high-order sliding-mode differentiator, a robust decentralized controller is obtained. Numerical results are presented to illustrate the performance of the proposed control scheme and its robustness properties. (author)

  20. Sensorless sliding mode torque control of an IPMSM drive based on active flux concept

    Directory of Open Access Journals (Sweden)

    A.A. Hassan

    2012-03-01

    Full Text Available This paper investigates a novel direct torque control of a sensorless interior permanent magnet synchronous motor based on a sliding mode technique. The speed and position of the interior permanent magnet synchronous motor are estimated online based on active flux concept. To overcome the large ripple content associated with the direct torque, a torque/flux sliding mode controller has been employed. Two integral surface functions are used to construct the sliding mode controller. The command voltage is estimated from the torque and flux errors based on the two switching functions. The idea of the total sliding mode is used to eliminate the problem of reaching phase stability. The space vector modulation is combined with the sliding mode controller to ensure minimum torque and flux ripples and provides high resolution voltage control. The proposed scheme has the advantages of simple implementation, and does not require an external signal injection. In addition, it combines the merits of the direct torque control, sliding mode controller, and space vector modulation besides to the sensorless control. Simulation works are carried out to demonstrate the ability of the proposed scheme at different operating conditions. The results confirm the high performance of the proposed scheme at standstill, low and high speeds including load disturbance and parameters variation.

  1. Second-Order Geometric Sliding Mode Attitude Observer with Application to Quadrotor on a Test Bench

    Directory of Open Access Journals (Sweden)

    Honglei An

    2013-01-01

    Full Text Available A sliding mode observer design framework is proposed based on the Lie group method of numerical integration on manifolds, and a Second-Order Geometric Sliding Mode Attitude Observer (SOGSMAO is designed for angular velocity estimation of quadrotor attitude. The algorithm constructs feedback in the angular velocity space and the space of equivalent Lie algebra of unit quaternion space, respectively. It avoids not only the complexity of constructing feedback in unit quaternion space but also the process of mandatory rescaling which is seen to deteriorate the accuracy of the angular velocity estimates during sliding. The performance of SOGSMAO is compared with traditional quaternion based sliding mode observer in which multiplicative quaternion correction is used and the results show that SOGSMAO gains better tracking performance. Then SOGSMAO is realized on a test bed and the effectiveness of the observer algorithm is verified by experimental studies.

  2. Frequency-shaped and observer-based discrete-time sliding mode control

    CERN Document Server

    Mehta, Axaykumar

    2015-01-01

    It is well established that the sliding mode control strategy provides an effective and robust method of controlling the deterministic system due to its well-known invariance property to a class of bounded disturbance and parameter variations. Advances in microcomputer technologies have made digital control increasingly popular among the researchers worldwide. And that led to the study of discrete-time sliding mode control design and its implementation. This brief presents, a method for multi-rate frequency shaped sliding mode controller design based on switching and non-switching type of reaching law. In this approach, the frequency dependent compensator dynamics are introduced through a frequency-shaped sliding surface by assigning frequency dependent weighing matrices in a linear quadratic regulator (LQR) design procedure. In this way, the undesired high frequency dynamics or certain frequency disturbance can be eliminated. The states are implicitly obtained by measuring the output at a faster rate than th...

  3. A Robust Tracking Control System Design for Autonomous Underwater Vehicles Based on Sliding Mode Control

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seung Yun [Agency for Defense Development (Korea, Republic of); Lee, Man Hyung [Pusan National University (Korea, Republic of)

    1998-02-01

    In this paper, a robust path tracking and diving control system of Autonomous Underwater Vehicle based on sliding mode control is presented. We have also d signed augmented equivalent control inputs by analyzing the sliding mode with the reaching mode. This can enhance the reaching rate, and improve chattering problems, that is, noise caused by the control plane actuator of the vehicle, which is one of the problems that occur when sliding mode control is used. Also to resolve the steady state error generated in the path tracker under current effect, a modified sliding plane is constructed. Also a redesigned sliding plane and control input using transformation matrix is proposed to do easy design of MIMO depth controller. For state variables that cannot be measured directly, reduced order sliding mode control is used to design an observer. The performance of designed path tracker and depth controller is investigated by computer simulation. The results show that the proposed control system has robust performance to parameter variation, modelling error and disturbance. (author). 12 refs., 14 figs., 1 tab.

  4. Synchronization of Two Fractional-Order Chaotic Systems via Nonsingular Terminal Fuzzy Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Xiaona Song

    2017-01-01

    Full Text Available The synchronization of two fractional-order complex chaotic systems is discussed in this paper. The parameter uncertainty and external disturbance are included in the system model, and the synchronization of the considered chaotic systems is implemented based on the finite-time concept. First, a novel fractional-order nonsingular terminal sliding surface which is suitable for the considered fractional-order systems is proposed. It is proven that once the state trajectories of the system reach the proposed sliding surface they will converge to the origin within a given finite time. Second, in terms of the established nonsingular terminal sliding surface, combining the fuzzy control and the sliding mode control schemes, a novel robust single fuzzy sliding mode control law is introduced, which can force the closed-loop dynamic error system trajectories to reach the sliding surface over a finite time. Finally, using the fractional Lyapunov stability theorem, the stability of the proposed method is proven. The proposed method is implemented for synchronization of two fractional-order Genesio-Tesi chaotic systems with uncertain parameters and external disturbances to verify the effectiveness of the proposed fractional-order nonsingular terminal fuzzy sliding mode controller.

  5. AN INTELLIGENT NEURO-FUZZY TERMINAL SLIDING MODE CONTROL METHOD WITH APPLICATION TO ATOMIC FORCE MICROSCOPE

    Directory of Open Access Journals (Sweden)

    Seied Yasser Nikoo

    2016-11-01

    Full Text Available In this paper, a neuro-fuzzy fast terminal sliding mode control method is proposed for controlling a class of nonlinear systems with bounded uncertainties and disturbances. In this method, a nonlinear terminal sliding surface is firstly designed. Then, this sliding surface is considered as input for an adaptive neuro-fuzzy inference system which is the main controller. A proportinal-integral-derivative controller is also used to asist the neuro-fuzzy controller in order to improve the performance of the system at the begining stage of control operation. In addition, bee algorithm is used in this paper to update the weights of neuro-fuzzy system as well as the parameters of the proportinal-integral-derivative controller. The proposed control scheme is simulated for vibration control in a model of atomic force microscope system and the results are compared with conventional sliding mode controllers. The simulation results show that the chattering effect in the proposed controller is decreased in comparison with the sliding mode and the terminal sliding mode controllers. Also, the method provides the advantages of fast convergence and low model dependency compared to the conventional methods.

  6. Universal fuzzy integral sliding-mode controllers for stochastic nonlinear systems.

    Science.gov (United States)

    Gao, Qing; Liu, Lu; Feng, Gang; Wang, Yong

    2014-12-01

    In this paper, the universal integral sliding-mode controller problem for the general stochastic nonlinear systems modeled by Itô type stochastic differential equations is investigated. One of the main contributions is that a novel dynamic integral sliding mode control (DISMC) scheme is developed for stochastic nonlinear systems based on their stochastic T-S fuzzy approximation models. The key advantage of the proposed DISMC scheme is that two very restrictive assumptions in most existing ISMC approaches to stochastic fuzzy systems have been removed. Based on the stochastic Lyapunov theory, it is shown that the closed-loop control system trajectories are kept on the integral sliding surface almost surely since the initial time, and moreover, the stochastic stability of the sliding motion can be guaranteed in terms of linear matrix inequalities. Another main contribution is that the results of universal fuzzy integral sliding-mode controllers for two classes of stochastic nonlinear systems, along with constructive procedures to obtain the universal fuzzy integral sliding-mode controllers, are provided, respectively. Simulation results from an inverted pendulum example are presented to illustrate the advantages and effectiveness of the proposed approaches.

  7. Chaos Control in Memristor-based Oscillators Using Intelligent Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Amir Hossein Abolmasoumi

    2014-10-01

    Full Text Available In this paper, Intelligent Sliding Mode Control of chaos in a memristor- based Chua’s oscillator is investigated. In order to gain stabilization and tracking of a sinusoidal input, an appropriate sliding surface is proposed and sliding gain is tuned. Also, to avoid the chattering phenomenon in traditional sliding mode controller, and to reduce the hitting time of the controlled system, an especial genetic algorithm optimization method is suggested. By defining a new objective function and searching for optimal the controller parameters the convergence time and chattering are reduced considerably. The usefulness of the proposed controller with intelligent tuning method for chaos control of memristorbased oscillators is demonstrated in memristor- based Chua's circuit.

  8. Investigation on the Development of a Sliding Mode Controller for Constant Power Loads in Microgrids

    Directory of Open Access Journals (Sweden)

    Eklas Hossain

    2017-07-01

    Full Text Available To implement renewable energy resources, microgrid systems have been adopted and developed into the technology of choice to assure mass electrification in the next decade. Microgrid systems have a number of advantages over conventional utility grid systems, however, they face severe instability issues due to the continually increasing constant power loads. To improve the stability of the entire system, the load side compensation technique is chosen because of its robustness and cost effectiveness. In this particular occasion, a sliding mode controller is developed for a microgrid system in the presence of constant power loads to assure a certain control objective of keeping the output voltage constant at 480 V. After that, a robustness analysis of the sliding mode controller against parametric uncertainties was performed and the sliding mode controller’s robustness against parametric uncertainties, frequency variations, and additive white Gaussian noise (AWGN are presented. Later, the performance of the proportional integral derivative (PID and sliding mode controller are compared in the case of nonlinearity, parameter uncertainties, and noise rejection to justify the selection of the sliding mode controller over the PID controller. All the necessary calculations are reckoned mathematically and results are verified in a virtual platform such as MATLAB/Simulink with a positive outcome.

  9. Continuous Recursive Sliding Mode Control for Hypersonic Flight Vehicle with Extended Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Yunjie Wu

    2015-01-01

    Full Text Available A continuous recursive sliding mode controller (CRSMC with extended disturbance observer (EDO is proposed for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV in the presence of multiple uncertainties under control constraints. Firstly, sliding mode tracking controller based on a set of novel recursive sliding mode manifolds is presented, in which the chattering problem is reduced. The CRSMC possesses the merits of both nonsingular terminal sliding mode controller (NTSMC and high-order sliding mode controller (HOSMC. Then antiwindup controller is designed according to the input constraints, which adds a dynamic compensation factor in the CRSMC. For the external disturbance of system, an improved disturbance observer based on extended disturbance observer (EDO is designed. The external disturbance is estimated by the disturbance observer and the estimated value is regarded as compensation in CRSMC for disturbance. The stability of the proposed scheme is analyzed by Lyapunov function theory. Finally, numerical simulation is conducted for cruise flight dynamics of HFV, where altitude is 110000 ft, velocity is 15060 ft/s, and Mach is 15. Simulation results show the validity of the proposed approach.

  10. Fixed switching frequency sliding mode control using an hysteresis band controller

    OpenAIRE

    Repecho del Corral, Víctor; Biel Solé, Domingo; Fossas Colet, Enric

    2014-01-01

    This paper presents a hysteresis band controller in charge of fixing the switching frequency of a sliding mode controller. The proposed control measures the switching period of the control signal and modifies the hysteresis band of the comparator to regulate the switching frequency of the sliding motion. The switching frequency control system is modelled and a design criterion of the control parameters is derived to guarantee the closed loop stability.

  11. Avoidance High-Frequency Chattering Second-Order Sliding Mode Controller Design: Buck Converter in Wind Power System

    Directory of Open Access Journals (Sweden)

    Yigeng Huangfu

    2012-01-01

    Full Text Available This paper mainly discussed a method of high-frequency second-order sliding mode control for Buck converter in wind power systems. Because the wind energy of nature is always unpredictable and intermittent, the robust control such as sliding mode control is adopted in past literatures. In order to remove the high frequency chattering problem when the traditional sliding mode achieves convergence, the second order sliding mode algorithm is reviewed firstly. Meanwhile, the Buck converter taken as a step-down converter is usually adopted in wind power system, because of its simple structure and good linearity. Under those conditions, the second order sliding mode controller is designed based on Buck converter, especially in high-power wind generation system. The experimental results illustrate that the theory of second order sliding mode can be used in high-power Buck converter. It provides one novel avoidance high frequency chattering method for the technology development of new energy generation system.

  12. Chattering-Free Neuro-Sliding Mode Control of 2-DOF Planar Parallel Manipulators

    Directory of Open Access Journals (Sweden)

    Tien Dung Le

    2013-01-01

    Full Text Available This paper proposes a novel chattering free neuro-sliding mode controller for the trajectory tracking control of two degrees of freedom (DOF parallel manipulators which have a complicated dynamic model, including modelling uncertainties, frictional uncertainties and external disturbances. A feedforward neural network (NN is combined with an error estimator to completely compensate the large nonlinear uncertainties and external disturbances of the parallel manipulators. The online weight tuning algorithms of the NN and the structure of the error estimator are derived with the strict theoretical stability proof of the Lyapunov theorem. The upper bound of uncertainties and the upper bound of the approximation errors are not required to be known in advance in order to guarantee the stability of the closed-loop system. The example simulation results show the effectiveness of the proposed control strategy for the tracking control of a 2-DOF parallel manipulator. It results in its being chattering-free, very small tracking errors and its robustness against uncertainties and external disturbances.

  13. Sliding Mode Observer and Control Design with Adaptive Parameter Estimation for a Supersonic Flight Vehicle

    Directory of Open Access Journals (Sweden)

    M. Bahrami

    2010-01-01

    Full Text Available Design and synthesis of a nonlinear generic supersonic flight vehicle longitudinal dynamics control for angle-of-attack, AOA, output tracking in the atmospheric flight is presented based on sliding mode control. A sliding mode observer is invoked to estimate AOA which is difficult to measure in practice. Large parameter uncertainties accommodation envisaged by designing adaptive mechanisms for both the control and observer and high chattering authority due to large deviations of aerodynamic coefficients arising from wind-tunnel measurements are inhibited. The employed method enables the sliding mode control design to exhibit the desired dynamic properties during the entire output-tracking process. Simulations results are presented to demonstrate the performance, robustness, and stability.

  14. Sliding mode disturbance observer-based control of a twin rotor MIMO system.

    Science.gov (United States)

    Rashad, Ramy; El-Badawy, Ayman; Aboudonia, Ahmed

    2017-07-01

    This work proposes a robust tracking controller for a helicopter laboratory setup known as the twin rotor MIMO system (TRMS) using an integral sliding mode controller. To eliminate the discontinuity in the control signal, the controller is augmented by a sliding mode disturbance observer. The actuator dynamics is handled using a backstepping approach which is applicable due to the continuous chattering-free nature of the command signals generated using the disturbance observer based controller. To avoid the complexity of analytically differentiating the command signals, a first order sliding mode differentiator is used. Stability analysis of the closed loop system and the ultimate boundedness of the tracking error is proved using Lyapunov stability arguments. The proposed controller is validated by several simulation studies and is compared to other schemes in the literature. Experimental results using a hardware-in-the-loop system validate the robustness and effectiveness of the proposed controller. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Sliding-Mode Synchronization Control for Uncertain Fractional-Order Chaotic Systems with Time Delay

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    Haorui Liu

    2015-06-01

    Full Text Available Specifically setting a time delay fractional financial system as the study object, this paper proposes a single controller method to eliminate the impact of model uncertainty and external disturbances on the system. The proposed method is based on the stability theory of Lyapunov sliding-mode adaptive control and fractional-order linear systems. The controller can fit the system state within the sliding-mode surface so as to realize synchronization of fractional-order chaotic systems. Analysis results demonstrate that the proposed single integral, sliding-mode control method can control the time delay fractional power system to realize chaotic synchronization, with strong robustness to external disturbance. The controller is simple in structure. The proposed method was also validated by numerical simulation.

  16. Active Disturbance Rejection with Sliding Mode Control Based Course and Path Following for Underactuated Ships

    Directory of Open Access Journals (Sweden)

    Ronghui Li

    2013-01-01

    Full Text Available The compound control of active-disturbance-rejection control (ADRC with sliding mode is proposed to improve the performance of the closed-loop system and deal with the constraint condition problem of a surface ship. The advantages of ADRC with sliding mode were verified by ship course control simulations. Meanwhile, to solve the path-following problem of underactuated surface ships with uncertainties of internal dynamic and external disturbances, the ADRC controller with sliding mode is introduced to steer the ship to follow the desired path. In order to overcome the cross-track error caused by wind and current, drift angle is compensated in the controller by designing a coordinate transformation equation. Simulations were performed on a nonlinear kinematics model of a training ship to validate the stability and excellent robustness of the proposed path-following controller.

  17. The Dynamics and Sliding Mode Control of Multiple Cooperative Welding Robot Manipulators

    Directory of Open Access Journals (Sweden)

    Bin Zi

    2012-08-01

    Full Text Available This paper deals with the design, dynamic modelling and sliding mode control of multiple cooperative welding robot manipulators (MWRMs. The MWRMs can handle complex tasks that are difficult or even impossible for a single manipulator. The kinematics and dynamics of the MWRMs are studied on the basis of the Denavit-Hartenberg and Lagrange method. Following that, considering the MWRM system with nonlinear and unknown disturbances, a non-singular terminal sliding mode control strategy is designed. By means of the Lyapunov function, the stability of the controller is proved. Simulation results indicate that the good control performance of the MWRMs is achieved by the non-singular terminal sliding mode controller, which also illustrates the correctness of the dynamic modelling and effectiveness of the proposed control strategy.

  18. Disturbance observer based sliding mode control of nonlinear mismatched uncertain systems

    Science.gov (United States)

    Ginoya, Divyesh; Shendge, P. D.; Phadke, S. B.

    2015-09-01

    This paper presents a new design of multiple-surface sliding mode control for a class of nonlinear uncertain systems with mismatched uncertainties and disturbances. In the method of multiple-surface sliding mode control, it is required to compensate for the derivatives of the virtual inputs which gives rise to the so-called problem of 'explosion of terms'. In this paper a disturbance observer based multiple-surface sliding mode control is proposed to estimate the uncertainties as well as the derivative of the virtual inputs to overcome this problem. The practical stability of the overall system is proved. The effectiveness of the proposed control strategy is illustrated via simulation of a benchmark problem and comparison with other control strategies. The proposed scheme is validated by implementing it on a serial flexible joint manipulator in the laboratory.

  19. Adaptive fuzzy sliding mode control for synchronization of uncertain fractional order chaotic systems

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Tsung-Chih, E-mail: tclin@fcu.edu.tw [Department of Electronic Engineering, Feng-Chia University, Taichung, Taiwan (China); Lee, Tun-Yuan [Department of Electronic Engineering, Feng-Chia University, Taichung, Taiwan (China); Balas, Valentina E. [Aurel Vlaicu University of Arad, B-dul Revolutiei 77, 310130 Arad (Romania)

    2011-10-15

    Highlights: > We study uncertain fractional order chaotic systems synchronization. > Lyapunov synthesis is used to derive control law and adaptive laws. > Based on sliding mode control, chattering phenomena in the control effort can be reduced. - Abstract: This paper deals with chaos synchronization between two different uncertain fractional order chaotic systems based on adaptive fuzzy sliding mode control (AFSMC). With the definition of fractional derivatives and integrals, a fuzzy Lyapunov synthesis approach is proposed to tune free parameters of the adaptive fuzzy controller on line by output feedback control law and adaptive law. Moreover, chattering phenomena in the control efforts can be reduced. The sliding mode design procedure not only guarantees the stability and robustness of the proposed AFSMC, but also the external disturbance on the synchronization error can be attenuated. The simulation example is included to confirm validity and synchronization performance of the advocated design methodology.

  20. High order sliding mode control of a DFIM supplied by two power inverters

    Directory of Open Access Journals (Sweden)

    Zinelaabidine Boudjema

    2015-06-01

    Full Text Available Traditional vector control structures which include proportional-integral (PI regulator for the speed of a doubly fed induction motor (DFIM driven have some disadvantages such as parameter tuning complications, mediocre dynamic performances and reduced robustness. Thus, based on the analysis of the mathematical model of a DFIM supplied by two indirect inverters, this paper addresses a nonlinear control algorithm based on high order sliding mode. The conventional sliding mode control has large chattering on the electromagnetic torque developed by the DFIM. In order to solve this problem, the second order sliding mode technique is used. The simulation results show the effectiveness of the proposed method especially in chattering-free behavior, response to sudden load torque variations and robustness against machine parameters variations.

  1. Tracking Control Design Using Sliding Mode Techniques for Satellite Formation Flying

    Directory of Open Access Journals (Sweden)

    Hyung-Chu Lim

    2003-12-01

    Full Text Available Satellite formation flying is currently an active area of research in the aerospace engineering. So it has been researched by various authors. In this study, a tracking controller using sliding mode techniques was designed to control a satellite for the satellite formation flying. In general, Hill's equations are used to describe the relative motion of the follower satellite with respect to the leader satellite. However the modified Hill's equations considering the J_2 perturbation were used for the design of sliding mode controller. The extended Kalman filter was applied to estimate the state vector based on the measurements of relative distance and velocity between two satellites. The simulation results show that the follower satellite tracks the desired trajectory well by thruster operations based on the sliding mode control law.

  2. A Robust Control Concept for Hydraulic Drives Based on Second Order Sliding Mode Disturbance Compensation

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben O.; Johansen, Per

    2017-01-01

    in hydraulic drive controls have been presented in various literature, demonstrating the possible successful application of these. However, a major drawback is the presence of e.g. valve dynamics which often necessitates the usage of continuous approximations of discontinuities in order to avoid control...... observer based control etc., and several examples of such approaches have been presented in literature. The latter case appear especially interesting as a sliding mode actually takes place, but only the low-pass filtered sliding mode algorithm output is used in the actual control input. However...

  3. Synchronization between Fractional-Order and Integer-Order Hyperchaotic Systems via Sliding Mode Controller

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    Yan-Ping Wu

    2013-01-01

    Full Text Available The synchronization between fractional-order hyperchaotic systems and integer-order hyperchaotic systems via sliding mode controller is investigated. By designing an active sliding mode controller and choosing proper control parameters, the drive and response systems are synchronized. Synchronization between the fractional-order Chen chaotic system and the integer-order Chen chaotic system and between integer-order hyperchaotic Chen system and fractional-order hyperchaotic Rössler system is used to illustrate the effectiveness of the proposed synchronization approach. Numerical simulations coincide with the theoretical analysis.

  4. Sliding Mode Control of PMSG Wind Turbine Based on Enhanced Exponential Reaching Law

    DEFF Research Database (Denmark)

    Mozayan, Seyed Mehdi; Saad, Maarouf; Vahedi, Hani

    2016-01-01

    This paper proposes a Sliding Mode Control (SMC) based scheme for a variable speed, direct-driven Wind Energy Conversion Systems (WECS) equipped with Permanent Magnet Synchronous Generator (PMSG) connected to the grid. In this work, diode rectifier, boost converter, Neutral Point Clamped (NPC...... great performance in complicated nonlinear systems control such as WECS. The proposed control strategy modifies Reaching Law (RL) of sliding mode technique to reduce chattering issue and to improve THD property compared to conventional reaching law SMC. The effectiveness of the proposed control strategy...

  5. Adaptive Terminal Sliding Mode Control of Electromagnetic Spacecraft Formation Flying in Near-Earth Orbits

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    Jingrui Zhang

    2014-02-01

    Full Text Available An adaptive terminal sliding mode control for six-degree-of-freedom electromagnetic spacecraft formation flying (EMFF in near-Earth orbits is presented. By using terminal sliding mode (TSM technique, the output tracking error can converge to zero in finite time, and strong robustness with respect to disturbance forces can be guaranteed. Based on a rotated frame Fr and the adaptive TSM controller, the special magnetic moment of the steerable magnetic dipole is computed. The angular momentum management strategy (AMM is implemented in a periodically switching fashion, by which the angular momentum buildup was limited. Illustrative simulations of EMFF are conducted to verify the effectiveness of the proposed controller.

  6. High Order Sliding Mode Control of Doubly-fed Induction Generator under Unbalanced Grid Faults

    DEFF Research Database (Denmark)

    Zhu, Rongwu; Chen, Zhe; Wu, Xiaojie

    2013-01-01

    This paper deals with a doubly-fed induction generator-based (DFIG) wind turbine system under grid fault conditions such as: unbalanced grid voltage, three-phase grid fault, using a high order sliding mode control (SMC). A second order sliding mode controller, which is robust with respect...... to matched internal or external disturbances, fast transient response and finite reaching time, is employed to reduce chattering phenomenon caused by high frequency switching of SMC, which serious exists in lower order SMC, and to overcome parameter dependence of traditional proportional integral (PI...

  7. Integral backstepping sliding mode control for underactuated systems: swing-up and stabilization of the Cart-Pendulum System.

    Science.gov (United States)

    Adhikary, Nabanita; Mahanta, Chitralekha

    2013-11-01

    In this paper an integral backstepping sliding mode controller is proposed for controlling underactuated systems. A feedback control law is designed based on backstepping algorithm and a sliding surface is introduced in the final stage of the algorithm. The backstepping algorithm makes the controller immune to matched and mismatched uncertainties and the sliding mode control provides robustness. The proposed controller ensures asymptotic stability. The effectiveness of the proposed controller is compared against a coupled sliding mode controller for swing-up and stabilization of the Cart-Pendulum System. Simulation results show that the proposed integral backstepping sliding mode controller is able to reject both matched and mismatched uncertainties with a chattering free control law, while utilizing less control effort than the sliding mode controller. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  8. Application of sliding mode methods to the design of reconfigurable flight control systems

    Science.gov (United States)

    Wells, Scott Russell

    Observer-based sliding mode control is investigated for application to aircraft reconfigurable flight control. A comprehensive overview of reconfigurable flight control is given, including a review of the current state-of-the-art within the subdisciplines of fault detection, parameter identification, adaptive control schemes, and dynamic control allocation. Of the adaptive control methods reviewed, sliding mode control (SMC) appears very promising due its property of invariance to matched uncertainty. An overview of sliding mode control is given and its remarkable properties are demonstrated by example. Sliding mode methods, however, are difficult to implement because unmodeled parasitic dynamics cause immediate and severe instability. This presents a challenge for all practical applications with limited bandwidth actuators. One method to deal with parasitic dynamics is the use of an asymptotic observer in the feedback path. Observer-based SMC is investigated, and a method for selecting observer gains is offered. An additional method for shaping the feedback loop using a filter is also developed. It is shown that this SMC prefilter is equivalent to a form of model reference hedging. A complete design procedure is given which takes advantage of the sliding mode boundary layer to recast the SMC as a linear control law. Frequency domain loop shaping is then used to design the sliding manifold. Finally, three aircraft applications are demonstrated. An F-18/HARV is used to demonstrate a SISO pitch rate tracking controller. It is also used to demonstrate a MIMO lateral-directional roll rate tracking controller. The last application is a full linear six degree-of-freedom advanced tailless fighter model. The observer-based SMC is seen to provide excellent tracking with superior robustness to parameter changes and actuator failures.

  9. Finite-Time Reentry Attitude Control Using Time-Varying Sliding Mode and Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Xuzhong Wu

    2015-01-01

    Full Text Available This paper presents the finite-time attitude control problem for reentry vehicle with redundant actuators in consideration of planet uncertainties and external disturbances. Firstly, feedback linearization technique is used to cancel the nonlinearities of equations of motion to construct a basic mode for attitude controller. Secondly, two kinds of time-varying sliding mode control methods with disturbance observer are integrated with the basic mode in order to enhance the control performance and system robustness. One method is designed based on boundary layer technique and the other is a novel second-order sliding model control method. The finite-time stability analyses of both resultant closed-loop systems are carried out. Furthermore, after attitude controller produces the torque commands, an optimization control allocation approach is introduced to allocate them into aerodynamic surface deflections and on-off reaction control system thrusts. Finally, the numerical simulation results demonstrate that both of the time-varying sliding mode control methods are robust to uncertainties and disturbances without chattering phenomenon. Moreover, the proposed second-order sliding mode control method possesses better control accuracy.

  10. Sliding Mode Control of the X-33 with an Engine Failure

    Science.gov (United States)

    Shtessel, Yuri B.; Hall, Charles E.

    2000-01-01

    Ascent flight control of the X-3 is performed using two XRS-2200 linear aerospike engines. in addition to aerosurfaces. The baseline control algorithms are PID with gain scheduling. Flight control using an innovative method. Sliding Mode Control. is presented for nominal and engine failed modes of flight. An easy to implement, robust controller. requiring no reconfiguration or gain scheduling is demonstrated through high fidelity flight simulations. The proposed sliding mode controller utilizes a two-loop structure and provides robust. de-coupled tracking of both orientation angle command profiles and angular rate command profiles in the presence of engine failure, bounded external disturbances (wind gusts) and uncertain matrix of inertia. Sliding mode control causes the angular rate and orientation angle tracking error dynamics to be constrained to linear, de-coupled, homogeneous, and vector valued differential equations with desired eigenvalues. Conditions that restrict engine failures to robustness domain of the sliding mode controller are derived. Overall stability of a two-loop flight control system is assessed. Simulation results show that the designed controller provides robust, accurate, de-coupled tracking of the orientation angle command profiles in the presence of external disturbances and vehicle inertia uncertainties, as well as the single engine failed case. The designed robust controller will significantly reduce the time and cost associated with flying new trajectory profiles or orbits, with new payloads, and with modified vehicles

  11. Design of practical sliding-mode controllers with constant switching frequency for power converters

    Energy Technology Data Exchange (ETDEWEB)

    Navarro-Lopez, Eva M. [School of Computer Science, Centre for Interdisciplinary Computational and Dynamical Analysis, The University of Manchester, Oxford Road, Kilburn Building, Manchester M13 9PL (United Kingdom); Cortes, Domingo [Seccion de Mecatronica, Departamento de Ingenieria Electrica, CINVESTAV-IPN, Av. IPN 2508, Col. San Pedro Zacatenco, 07360 Mexico City (Mexico); Castro, Christian [Centro de Investigacion en Computacion del IPN, Av. Jose Othon de Mendizabal s/n, Col. Nueva Industrial Vallejo, 07738 Mexico City (Mexico)

    2009-05-15

    A novel experimentally motivated method in order to design a family of easy-to-implement sliding-mode controllers for power converters is proposed. Two main results are presented. First, the relation between sliding-mode control and average control is reinterpreted so that the limitation of the switching frequency for the closed-loop system is achieved in a more direct way than other methods so far reported in the literature. For this purpose, a class of sliding surfaces which makes the associated equivalent control be the system average control is proposed. Second, the achievement of a constant switching frequency in the controlled system is assured without requiring the sliding-mode-based controller to be modified, unlike most previous works. As a result, the proposed sliding surfaces-type can be directly implemented via a pulse-width modulator. The control methodology is implemented for the voltage control in a boost converter prototype in which the load is considered unknown. Experimental results confirm high performance and robustness under parameters variation. Furthermore, the solution proposed is easy to implement and well-suited for other power converters. (author)

  12. Novel Adaptive Sliding Mode Control with Nonlinear Disturbance Observer for SMT Assembly Machine

    Directory of Open Access Journals (Sweden)

    Rongrong Qian

    2016-01-01

    Full Text Available This paper presents a novel adaptive sliding mode control based on nonlinear sliding surface with disturbance observer (ANSMC-DOB for precision trajectory tracking control of a surface mount technology (SMT assembly machine. A two-degree-of-freedom model with time-varying parameter uncertainties and disturbances is built to describe the first axial mode of the pick-place actuation axis of the machine. According to the principle of variable damping ratio coefficient which makes the system have a nonovershoot transient response and a short settling time in the second-order system, the nonlinear sliding surface is designed for the sliding mode control (SMC. Since the upper bound value of the disturbances is unknown, the adaptive gain estimation is applied to replace the switching gain in the SMC. In order to settle the problem of SMC unrobust to the mismatched parameter uncertainties and disturbances, the nonlinear disturbance observer is introduced to estimate the mismatched disturbances and form the novel controller of ANSMC-DOB. The stability of sliding surfaces and control laws are verified by the Lyapunov functions. The simulation research and comparative experiments are conducted to verify the improvement of positioning accuracy and robustness by the proposed ANSMC-DOB in the SMT assembly machine.

  13. A multitask sliding mode control for mismatched uncertain large-scale systems

    Science.gov (United States)

    Tsai, Yao-Wen; Van Huynh, Van

    2015-09-01

    A new sliding mode control (SMC) approach, output variables only, single phase only and chattering phenomenon free, is presented for a class of mismatched uncertain large-scale systems. For a new multitask SMC, it is not required that the system states are available. Moreover, the sliding function in this study just depends on output variables. Using an exponential type sliding surface, the system states are always in the sliding mode at the beginning time t = 0. Using a newly appropriate linear matrix inequality stability conditions by the Lyapunov method are derived such that each subsystem in the new sliding mode is completely invariant to matched uncertainties. As a result, robustness of the mismatched uncertain large-scale systems can be assured throughout an entire response of the system starting from the initial time t = 0. In every subsystem, a scheme of decentralised control using only output states is proposed. In addition, a continuous controller is finally designed for chattering removal. Finally, a numerical example is used to demonstrate the efficacy of the proposed method.

  14. Vibration suppression in flexible structures via the sliding-mode control approach

    Science.gov (United States)

    Drakunov, S.; Oezguener, Uemit

    1994-01-01

    Sliding mode control became very popular recently because it makes the closed loop system highly insensitive to external disturbances and parameter variations. Sliding algorithms for flexible structures have been used previously, but these were based on finite-dimensional models. An extension of this approach for differential-difference systems is obtained. That makes if possible to apply sliding-mode control algorithms to the variety of nondispersive flexible structures which can be described as differential-difference systems. The main idea of using this technique for dispersive structures is to reduce the order of the controlled part of the system by applying an integral transformation. We can say that transformation 'absorbs' the dispersive properties of the flexible structure as the controlled part becomes dispersive.

  15. Adaptive Fuzzy Sliding Mode Tracking Control of Uncertain Underactuated Nonlinear Systems: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Faten Baklouti

    2016-01-01

    Full Text Available The trajectory tracking of underactuated nonlinear system with two degrees of freedom is tackled by an adaptive fuzzy hierarchical sliding mode controller. The proposed control law solves the problem of coupling using a hierarchical structure of the sliding surfaces and chattering by adopting different reaching laws. The unknown system functions are approximated by fuzzy logic systems and free parameters can be updated online by adaptive laws based on Lyapunov theory. Two comparative studies are made in this paper. The first comparison is between three different expressions of reaching laws to compare their abilities to reduce the chattering phenomenon. The second comparison is made between the proposed adaptive fuzzy hierarchical sliding mode controller and two other control laws which keep the coupling in the underactuated system. The tracking performances of each control law are evaluated. Simulation examples including different amplitudes of external disturbances are made.

  16. Synchronization of Fractional-Order Chaotic Systems with Gaussian Fluctuation by Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Yong Xu

    2013-01-01

    Full Text Available Chaotic systems are always influenced by some uncertainties and external disturbances. This paper investigates the problem of practical synchronization of fractional-order chaotic systems with Gaussian fluctuation. A fractional integral (FI sliding surface is proposed for synchronizing the uncertain fractional-order system, and then the sliding mode control technique is carried out to realize the synchronization of the given systems. One theorem about sliding mode controller is presented to prove that the proposed controller can make the system achieve synchronization. As a case study, the presented method is applied to the fractional-order Chen-Lü system, and simulation results show that the proposed control approach is capable to go against Gaussian noise well.

  17. Extended State Observer-Based Sliding Mode Control with New Reaching Law for PMSM Speed Control

    Directory of Open Access Journals (Sweden)

    Junzhang Qian

    2016-01-01

    Full Text Available In order to improve the performance of external disturbance rejection of permanent magnet synchronous motor (PMSM in speed control, sliding mode control with extended state observer is adopted in this paper. First, an exponential function-based sliding mode reaching law (ESMRL is developed. The ESMRL can dynamically adapt to the variations of the controlled system, which decrease the reaching time in reaching stage and void chattering in sliding motion stage while maintaining high tracking accuracy of the servo system. Then, an extended state observer (ESO is introduced to the controller to simultaneously estimate external disturbance and compensate the uncertainties. Simulation results demonstrate that the proposed method has better suppression of chattering effect and disturbance rejection ability while ensuring dynamic performance.

  18. Design of Second-Order Sliding Mode Guidance Law Based on the Nonhomogeneous Disturbance Observer

    Directory of Open Access Journals (Sweden)

    Huibo Zhou

    2014-01-01

    Full Text Available Considering the guidance problem of relative motion of missile target without the dynamic characteristics of missile autopilot in the interception planar, non-homogeneous disturbance observer is applied for finite-time estimation with respect to the target maneuvering affecting the guidance performance. Two guidance laws with finite-time convergence are designed by using a fast power rate reaching law and the prescribed sliding variable dynamics. The nonsingular terminal sliding mode surface is selected to improve dynamic characteristics of missile autopilot. Furthermore, the finite-time guidance law with dynamic delay characteristics is designed for the target maneuvering through adopting variable structure dynamic compensation. The simulation results demonstrate that, for different target maneuvering, the proposed guidance laws can restrain the sliding mode chattering problem effectively and make the missile hit the maneuvering target quickly and accurately with condition of corresponding assumptions.

  19. Parameter Identification and Synchronization of Uncertain Chaotic Systems Based on Sliding Mode Observer

    Directory of Open Access Journals (Sweden)

    Li-lian Huang

    2013-01-01

    Full Text Available The synchronization of nonlinear uncertain chaotic systems is investigated. We propose a sliding mode state observer scheme which combines the sliding mode control with observer theory and apply it into the uncertain chaotic system with unknown parameters and bounded interference. Based on Lyapunov stability theory, the constraints of synchronization and proof are given. This method not only can realize the synchronization of chaotic systems, but also identify the unknown parameters and obtain the correct parameter estimation. Otherwise, the synchronization of chaotic systems with unknown parameters and bounded external disturbances is robust by the design of the sliding surface. Finally, numerical simulations on Liu chaotic system with unknown parameters and disturbances are carried out. Simulation results show that this synchronization and parameter identification has been totally achieved and the effectiveness is verified very well.

  20. Super Twisting Second Order Sliding Mode Control for Position Tracking Control of Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    In this paper a control strategy based on second order sliding modes, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD), is proposed. The main target is to overcome problems with linear controllers deteriorating performance due to the strong...

  1. A Simple and Robust Sliding Mode Velocity Observer for Moving Coil Actuators in Digital Hydraulic Valves

    DEFF Research Database (Denmark)

    Nørgård, Christian; Schmidt, Lasse; Bech, Michael Møller

    2016-01-01

    This paper focuses on estimating the velocity and position of fast switching digital hydraulic valves actuated by electromagnetic moving coil actuators, based on measurements of the coil current and voltage. The velocity is estimated by a simple first-order sliding mode observer architecture...

  2. FUZZY SLIDING MODE CONTROLLER FOR DOUBLY FED INDUCTION MOTOR SPEED CONTROL

    Directory of Open Access Journals (Sweden)

    Y. Bekakra

    2015-08-01

    Full Text Available This paper, presents a Direct Field-Oriented Control (DFOC of doubly fed induction motor (DFIM with a fuzzy sliding mode controller (FSMC. Our aim is to make the speed control robust to parameter variations. The variation of motor parameters during operation degrades the performance of the controllers. The use of the nonlinear fuzzy sliding mode method provides very good performance for motor operation and robustness of the control law despite the external/internal perturbations. The chattering effects is eliminated by a particular function "sat" that presents a serious problem to applications of variable structure systems. The fuzzy sliding mode controller is designed in order to improve the control performances and to reduce the chattering phenomenon. In this technique the saturation function is replaced by a fuzzy inference system to smooth the control action. The proposed scheme gives fast dynamic response with no overshoot and zero static error. To show the validity and the effectiveness of the control method, simulation results are performed for the speed control of a doubly fed induction motor. Simulation results showed that improvement made by our approach compared to conventional sliding mode control (SMC with the presence of variations of the parameters of the motor, in particular the face of variation of moment of inertia and disturbances of load torque. The results show that the FSMC and SMC are robust against internal and external perturbations, but the FSMC is superior to SMC in eliminating chattering phenomena and response time.

  3. FUZZY SLIDING MODE CONTROLLER FOR DOUBLY FED INDUCTION MOTOR SPEED CONTROL

    Directory of Open Access Journals (Sweden)

    Y. Bekakra

    2013-12-01

    Full Text Available This paper, presents a Direct Field-Oriented Control (DFOC of doubly fed induction motor (DFIM with a fuzzy sliding mode controller (FSMC. Our aim is to make the speed control robust to parameter variations. The variation of motor parameters during operation degrades the performance of the controllers. The use of the nonlinear fuzzy sliding mode method provides very good performance for motor operation and robustness of the control law despite the external/internal perturbations. The chattering effects is eliminated by a particular function "sat" that presents a serious problem to applications of variable structure systems. The fuzzy sliding mode controller is designed in order to improve the control performances and to reduce the chattering phenomenon. In this technique the saturation function is replaced by a fuzzy inference system to smooth the control action. The proposed scheme gives fast dynamic response with no overshoot and zero static error. To show the validity and the effectiveness of the control method, simulation results are performed for the speed control of a doubly fed induction motor. Simulation results showed that improvement made by our approach compared to conventional sliding mode control (SMC with the presence of variations of the parameters of the motor, in particular the face of variation of moment of inertia and disturbances of load torque. The results show that the FSMC and SMC are robust against internal and external perturbations, but the FSMC is superior to SMC in eliminating chattering phenomena and response time.

  4. Designing of Proportional Sliding Mode Controller for Linear One Stage Inverted Pendulum

    Directory of Open Access Journals (Sweden)

    Anirban Banrejee

    2011-01-01

    Full Text Available The control of Inverted Pendulum (IP is a hugely complex task. A great deal of nonlinearity is present inherently and as well as affected by the surrounding external conditions. The sliding mode controller (SMC is very robust inherently. It is used in this paper to control the IP. This paper examines the designing of sliding mode controller (SMC for a linear inverted pendulum (IP. The paper highlights the important features of the sliding mode and also throws ample lights on the designing guidelines. The paper puts special impetus on the mathematical modeling of the controller. The robustness of the design of SMC with proportional control is amply displayed with the help of simple mathematics. It gives rise to a controller which can control a highly nonlinear system like IP quite efficiently. The performance of the SMC is compared with fuzzy and PID controller. The edge this controller poses is the key aspect of this paper. External disturbances and internal inaccuracies are also introduced to the system to bring out the robustness of the controller to the fore. Background on sliding mode and the pendulum are provided. Simulation results are displayed in a vivid manner and explained suitably.

  5. Chattering Suppression for DSP Based Sliding Mode Current Control of PM DC Drives

    DEFF Research Database (Denmark)

    Dal, Mehmet; Teodorescu, Remus

    2009-01-01

    This paper investigates several chattering suppression methods for DSP based implementation of sliding mode control (SMC). It concentrates on the ‘equivalent-control-dependent' and ‘state-dependent' gain adjustment methods proposed in recent theoretical studies, and tests the effectiveness...

  6. Adaptive sliding mode control of interleaved parallel boost converter for fuel cell energy generation system

    DEFF Research Database (Denmark)

    El Fadil, H.; Giri, F.; Guerrero, Josep M.

    2013-01-01

    This paper deals with the problem of controlling energy generation systems including fuel cells (FCs) and interleaved boost power converters. The proposed nonlinear adaptive controller is designed using sliding mode control (SMC) technique based on the system nonlinear model. The latter accounts...

  7. Sliding-Mode Observer for Speed and Position Sensorless Control of Linear-PMSM

    Directory of Open Access Journals (Sweden)

    Kazraji Saeed Masoumi

    2014-05-01

    Full Text Available The paper presents a sliding-mode observer that utilizes sigmoid function for speed and position sensorless control of permanent-magnet linear synchronous motor (PMLSM. In conventional sliding mode observer method there are the chattering phenomenon and the phase lag. Thus, in order to avoid the usage of the low pass filter and the phase compensator based on back EMF, in this paper a sliding mode observer with sigmoid function for detecting the back EMF in a PMLSM is designed to estimate the speed and the position of the rotor. Most of conventional sliding mode observers use sign or saturation functions which need low pass filter in order to detect back electromotive force (back EMF. In this paper a sigmoid function is used instead of discontinuous sign function to decrease undesirable chattering phenomenon. By reducing the chattering, detecting of the back EMF can be made directly from switching signal without any low pass filter. Thus the delay time in the proposed observer is eliminated because of the low pass filter. Furthermore, there is no need to compensate phase fault in position and speed estimating of linear-PMSM. Advantages of the proposed observer have been shown by simulation with MATLAB software.

  8. Fuzzy sliding-mode control with low pass filter to reduce chattering ...

    Indian Academy of Sciences (India)

    Inherent instability of SRIP in upright position and the presence of modelling uncertainty pose a challenge for control engineers. Sliding-mode control (SMC) is the most widely accepted robust control technique.Various versions of SMCs to stabilize SRIP have been reported in literature. Advantages of SMC come at the cost ...

  9. Design of passive fault-tolerant controllers of a quadrotor based on sliding mode theory

    Directory of Open Access Journals (Sweden)

    Merheb Abdel-Razzak

    2015-09-01

    Full Text Available Abstract In this paper, sliding mode control is used to develop two passive fault tolerant controllers for an AscTec Pelican UAV quadrotor. In the first approach, a regular sliding mode controller (SMC augmented with an integrator uses the robustness property of variable structure control to tolerate partial actuator faults. The second approach is a cascaded sliding mode controller with an inner and outer SMC loops. In this configuration, faults are tolerated in the fast inner loop controlling the velocity system. Tuning the controllers to find the optimal values of the sliding mode controller gains is made using the ecological systems algorithm (ESA, a biologically inspired stochastic search algorithm based on the natural equilibrium of animal species. The controllers are tested using SIMULINK in the presence of two different types of actuator faults, partial loss of motor power affecting all the motors at once, and partial loss of motor speed. Results of the quadrotor following a continuous path demonstrated the effectiveness of the controllers, which are able to tolerate a significant number of actuator faults despite the lack of hardware redundancy in the quadrotor system. Tuning the controller using a faulty system improves further its ability to afford more severe faults. Simulation results show that passive schemes reserve their important role in fault tolerant control and are complementary to active techniques

  10. Synchronizing Spatiotemporal Chaos via a Composite Disturbance Observer-Based Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Congyan Chen

    2014-01-01

    Full Text Available The sliding mode control schemes are investigated to synchronize two spatiotemporal chaotic systems, which are two arrays of a large number of coupled chaotic oscillators. Firstly, sliding mode manifolds with the desired performance are designed. The asymptotic convergence to the origin of the synchronization errors is also proved. However, the terms from parameter fluctuations in equivalent controls are usually impossible to be measured directly. So we regard them as lumped disturbances, but, for practical application, it is difficult to obtain the upper bound of lumped disturbances in advance which often results in a conservative sliding mode control law with large control effort, causing a large amount of chattering. To reduce the chattering and improve the performance of the system, a disturbance observer is designed to estimate the lumped disturbances. A composite synchronization controller that consists of a sliding mode feedback part and a feedforward compensation part based on disturbance observer is developed. The numerical simulation results are presented to show the effectiveness of the proposed methods.

  11. Free chattering hybrid sliding mode control for a class of non-linear systems

    DEFF Research Database (Denmark)

    Khooban, Mohammad-Hassan; Niknam, Taher; Blaabjerg, Frede

    2016-01-01

    In current study, in order to find the control of general uncertain nonlinear systems, a new optimal hybrid control approach called Optimal General Type II Fuzzy Sliding Mode (OGT2FSM) is presented. In order to estimate unknown nonlinear activities in monitoring dynamic uncertainties, the benefit...

  12. Sliding Mode Control for Bearingless Induction Motor Based on a Novel Load Torque Observer

    Directory of Open Access Journals (Sweden)

    Zebin Yang

    2016-01-01

    Full Text Available For the problem of low control performance of Bearingless Induction Motor (BIM control system in the presence of large load disturbance, a novel load torque sliding mode observer is proposed on the basis of establishing sliding mode speed control system. The load observer chooses the speed and load torque of the BIM control system as the observed objects, uses the speed error to design the integral sliding mode surface, and adds the low-pass filter to reduce the torque observation error. Meanwhile, the output of the load torque is used as the feedforward compensation for the control system, which can provide the required current for load changes and reduce the adverse influence of disturbance on system performance. Besides, considering that the load changes lead to the varying rotational inertia, the integral identification method is adopted to identify the rotational inertia of BIM, and the rotational inertia can be updated to the load observer in real time. The simulation and experiment results all show that the proposed method can track load torque accurately, improve the ability to resist disturbances, and ameliorate the operation quality of BIM control system. The chattering of sliding mode also is suppressed effectively.

  13. Super-twisting sliding mode control of torque and flux in permanent magnet synchronous machine drives

    DEFF Research Database (Denmark)

    Lascu, Christian; Boldea, Ion; Blaabjerg, Frede

    2013-01-01

    This paper investigates a permanent magnet synchronous motor drive controlled by a second-order variable structure control technique, known as the super-twisting sliding modes (STSM) control. The STSM controller is designed as a direct torque and flux controller and it works in the stator flux...

  14. Scaled Bilateral Teleoperation Using Discrete-Time Sliding-Mode Controller

    NARCIS (Netherlands)

    Khan, S.; Sabanovic, A.; Nergiz, A.O.

    2009-01-01

    In this paper, the design of a discrete-time sliding-mode controller based on Lyapunov theory is presented along with a robust disturbance observer and is applied to a piezostage for high-precision motion. A linear model of a piezostage was used with nominal parameters to compensate the disturbance

  15. Sliding Modes after the First Decade of the 21st Century State of the Art

    CERN Document Server

    Moreno, Jaime; Iriarte, Rafael

    2012-01-01

    The book presents the newest results of the major world research groups working in the area of Variable Structure Systems and Sliding Mode Control (VSS/SMC). The research activity of these groups is coordinated by the IEEE Technical Committee on Variable Structure Systems (VSS) and Sliding Modes (SM). The presented results include the reports of the research groups collaborating in a framework of the Unión European Union – México project of Fondo de Cooperación Internacional en Ciencia y Tecnología (FONCICyT) 93302 titled "Automatization and Monitoring of Energy Production Processes via Sliding Mode Control". The book starts with the overview of the sliding mode control concepts and algorithms that were developed and discussed in the last two decades The research papers are combined in three sections: Part I: VSS and SM Algorithms and their Analysis Part II: SMC Design Part III: Applications of VSS and SMC The book will be of interests of engineers, researchers and graduate students working in the area ...

  16. Automated adaptive sliding mode control scheme for a class of real ...

    Indian Academy of Sciences (India)

    Complicated systems; efficient automated adaptive sliding mode controlscheme; non-identical hyper-chaotic master/slave systems; synchronization error; numerical ... Department of Electrical Engineering, Birjand Branch, Islamic Azad University (IAU), Birjand, Iran; Department of Control Engineering, Faculty of Electrical ...

  17. Sliding mode control of DC-to-DC power converters using integral reconstructors

    Energy Technology Data Exchange (ETDEWEB)

    Sira-Ramirez, H. [CINVESTAV-IPN, Departamento de Ingenieria Electrica, Mexico (Mexico); Marquez-Contreras, R. [CNRS, Gif-sur-Ivette (France). Lab. des Signaux et Systemes; Fliess, M. [Ecole Normale Superieure de Cachan (France). Centre de Mathematiques et Leurs Applications

    2002-07-01

    A sliding mode feedback controller, based on integral reconstructors is developed for the regulation of the 'boost' DC-to-DC power converter circuit conduction in continuous conduction mode. The feedback control scheme uses only output capacitor voltage measurements, as well as knowledge of the available input signal, represented by the switch positions. The robustness of the feedback scheme is tested with abusively large, unmodelled, sudden load resistance variations. (Author)

  18. Global attractor alphabet of neural firing modes.

    Science.gov (United States)

    Baram, Yoram

    2013-08-01

    The elementary set, or alphabet, of neural firing modes is derived from the widely accepted conductance-based rectified firing-rate model. The firing dynamics of interacting neurons are shown to be governed by a multidimensional bilinear threshold discrete iteration map. The parameter-dependent global attractors of the map morph into 12 attractor types. Consistent with the dynamic modes observed in biological neuronal firing, the global attractor alphabet is highly visual and intuitive in the scalar, single-neuron case. As synapse permeability varies from high depression to high potentiation, the global attractor type varies from chaotic to multiplexed, oscillatory, fixed, and saturated. As membrane permeability decreases, the global attractor transforms from active to passive state. Under the same activation, learning and retrieval end at the same global attractor. The bilinear threshold structure of the multidimensional map associated with interacting neurons generalizes the global attractor alphabet of neuronal firing modes to multineuron systems. Selective positive or negative activation and neural interaction yield combinatorial revelation and concealment of stored neuronal global attractors.

  19. Dynamic performance enhancement of microgrids by advanced sliding mode controller

    Energy Technology Data Exchange (ETDEWEB)

    Sofla, Mohammadhassan Abdollahi [Electrical Engineering and Computer Science Dept., University of Toledo, Ohio (United States); Gharehpetian, Gevorg B. [Electrical Engineering Dept., Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2011-01-15

    Dynamics are the most important problems in the microgrid operation. In the islanded microgrid, the mismatch of parallel operations of inverters during dynamics can result in the instability. This paper considers severe dynamics which can occur in the microgrid. Microgrid can have different configurations with different load and generation dynamics which are facing voltage disturbances. As a result, microgrid has many uncertainties and is placed in the distribution network where is full of voltage disturbances. Moreover, characteristics of the distribution network and distributed energy resources in the islanded mode make microgrid vulnerable and easily lead to instability. The main aim of this paper is to discuss the suitable mathematical modeling based on microgrid characteristics and to design properly inner controllers to enhance the dynamics of microgrid with uncertain and changing parameters. This paper provides a method for inner controllers of inverter-based distributed energy resources to have a suitable response for different dynamics. Parallel inverters in distribution networks were considered to be controlled by nonlinear robust voltage and current controllers. Theoretical prove beyond simulation results, reveal evidently the effectiveness of the proposed controller. (author)

  20. Model-based Sliding Mode Controller of Anti-lock Braking System

    Science.gov (United States)

    Zheng, Lin; Luo, Yue-Gang; Kang, Jing; Shi, Zhan-Qun

    2016-05-01

    The anti-lock braking system (ABS) used in automobiles is used to prevent wheel from lockup and to maintain the steering ability and stability. The sliding mode controller is able to control nonlinear system steadily. In this research, a one-wheel dynamic model with ABS control is built up using model-based method. Using the sliding model controller, the simulation results by using Matlab/Simulink show qualified data compared with optimal slip rate. By using this method, the ABS brake efficiency is improved efficiently.

  1. High-performance fractional order terminal sliding mode control strategy for DC-DC Buck converter.

    Science.gov (United States)

    Wang, Jianlin; Xu, Dan; Zhou, Huan; Bai, Anning; Lu, Wei

    2017-01-01

    This paper presents an adaption of the fractional order terminal sliding mode control (AFTSMC) strategy for DC-DC Buck converter. The following strategy aims to design a novel nonlinear sliding surface function, with a double closed-loop structure of voltage and current. This strategy is a fusion of two characteristics: terminal sliding mode control (TSMC) and fractional order calculation (FOC). In addition, the influence of "the controller parameters" on the "performance of double closed-loop system" is investigated. It is observed that the value of terminal power has to be chosen to make a compromise between start-up and transient response of the converter. Therefore the AFTSMC strategy chooses the value of the terminal power adaptively, and this strategy can lead to the appropriate number of fractional order as well. Furthermore, through the fractional order analysis, the system can reach the sliding mode surface in a finite time. And the theoretical considerations are verified by numerical simulation. The performance of the AFTSMC and TSMC strategies is tested by computer simulations. And the comparison simulation results show that the AFTSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. Moreover, AFTSMC obtains a faster dynamical response, smaller steady-state error rate and lower overshoot.

  2. High-performance fractional order terminal sliding mode control strategy for DC-DC Buck converter.

    Directory of Open Access Journals (Sweden)

    Jianlin Wang

    Full Text Available This paper presents an adaption of the fractional order terminal sliding mode control (AFTSMC strategy for DC-DC Buck converter. The following strategy aims to design a novel nonlinear sliding surface function, with a double closed-loop structure of voltage and current. This strategy is a fusion of two characteristics: terminal sliding mode control (TSMC and fractional order calculation (FOC. In addition, the influence of "the controller parameters" on the "performance of double closed-loop system" is investigated. It is observed that the value of terminal power has to be chosen to make a compromise between start-up and transient response of the converter. Therefore the AFTSMC strategy chooses the value of the terminal power adaptively, and this strategy can lead to the appropriate number of fractional order as well. Furthermore, through the fractional order analysis, the system can reach the sliding mode surface in a finite time. And the theoretical considerations are verified by numerical simulation. The performance of the AFTSMC and TSMC strategies is tested by computer simulations. And the comparison simulation results show that the AFTSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. Moreover, AFTSMC obtains a faster dynamical response, smaller steady-state error rate and lower overshoot.

  3. Sliding-Mode Control Applied for Robust Control of a Highly Unstable Aircraft

    Science.gov (United States)

    Vetter, Travis Kenneth

    2002-01-01

    An investigation into the application of an observer based sliding mode controller for robust control of a highly unstable aircraft and methods of compensating for actuator dynamics is performed. After a brief overview of some reconfigurable controllers, sliding mode control (SMC) is selected because of its invariance properties and lack of need for parameter identification. SMC is reviewed and issues with parasitic dynamics, which cause system instability, are addressed. Utilizing sliding manifold boundary layers, the nonlinear control is converted to a linear control and sliding manifold design is performed in the frequency domain. An additional feedback form of model reference hedging is employed which is similar to a prefilter and has large benefits to system performance. The effects of inclusion of actuator dynamics into the designed plant is heavily investigated. Multiple Simulink models of the full longitudinal dynamics and wing deflection modes of the forward swept aero elastic vehicle (FSAV) are constructed. Additionally a linear state space models to analyze effects from various system parameters. The FSAV has a pole at +7 rad/sec and is non-minimum phase. The use of 'model actuators' in the feedback path, and varying there design, is heavily investigated for the resulting effects on plant robustness and tolerance to actuator failure. The use of redundant actuators is also explored and improved robustness is shown. All models are simulated with severe failure and excellent tracking, and task dependent handling qualities, and low pilot induced oscillation tendency is shown.

  4. Speed tracking control of pneumatic motor servo systems using observation-based adaptive dynamic sliding-mode control

    Science.gov (United States)

    Chen, Syuan-Yi; Gong, Sheng-Sian

    2017-09-01

    This study aims to develop an adaptive high-precision control system for controlling the speed of a vane-type air motor (VAM) pneumatic servo system. In practice, the rotor speed of a VAM depends on the input mass air flow, which can be controlled by the effective orifice area (EOA) of an electronic throttle valve (ETV). As the control variable of a second-order pneumatic system is the integral of the EOA, an observation-based adaptive dynamic sliding-mode control (ADSMC) system is proposed to derive the differential of the control variable, namely, the EOA control signal. In the ADSMC system, a proportional-integral-derivative fuzzy neural network (PIDFNN) observer is used to achieve an ideal dynamic sliding-mode control (DSMC), and a supervisor compensator is designed to eliminate the approximation error. As a result, the ADSMC incorporates the robustness of a DSMC and the online learning ability of a PIDFNN. To ensure the convergence of the tracking error, a Lyapunov-based analytical method is employed to obtain the adaptive algorithms required to tune the control parameters of the online ADSMC system. Finally, our experimental results demonstrate the precision and robustness of the ADSMC system for highly nonlinear and time-varying VAM pneumatic servo systems.

  5. Fuzzy sliding mode control of a doubly fed induction generator for wind energy conversion

    Directory of Open Access Journals (Sweden)

    A. Meroufel

    2013-12-01

    Full Text Available In this paper we present a nonlinear control using fuzzy sliding mode for wind energy conversion system based on a doubly-fed induction generator (DFIG supplied by an AC-AC converter. In the first place, we carried out briefly a study of modeling on the whole system. In order to control the power flowing between the stator of the DFIG and the grid, a proposed control design uses fuzzy logic technique is applied for implementing a fuzzy hitting control law to remove completely the chattering phenomenon on a conventional sliding mode control. The use of this method provides very satisfactory performance for the DFIG control, and the chattering effect is also reduced by the fuzzy mode. The machine is tested in association with a wind turbine. Simulations results are presented and discussed for the whole system.

  6. Adaptive Sliding Mode Robust Control for Virtual Compound-Axis Servo System

    Directory of Open Access Journals (Sweden)

    Yan Ren

    2013-01-01

    Full Text Available A structure mode of virtual compound-axis servo system is proposed to improve the tracking accuracy of the ordinary optoelectric tracking platform. It is based on the structure and principles of compound-axis servo system. A hybrid position control scheme combining the PD controller and feed-forward controller is used in subsystem to track the tracking error of the main system. This paper analyzes the influences of the equivalent disturbance in main system and proposes an adaptive sliding mode robust control method based on the improved disturbance observer. The sliding mode technique helps this disturbance observer to deal with the uncompensated disturbance in high frequency by making use of the rapid switching control value, which is based on the subtle error of disturbance estimation. Besides, the high-frequency chattering is alleviated effectively in this proposal. The effectiveness of the proposal is confirmed by experiments on optoelectric tracking platform.

  7. Decomposed Sliding Mode Control of the Drive with Interior Permanent Magnet Synchronous Motor and Flexible Coupling

    Directory of Open Access Journals (Sweden)

    Jan Vittek

    2013-01-01

    Full Text Available A decomposed sliding mode control of the drive with an interior permanent magnet synchronous motor and flexible coupling is presented. Decomposition exploits principles of vector control to divide motor into channel for control of magnetic flux and channel for control of torque separately. Sliding mode control principles are exploited to keep demanded value of magnetic flux and to control load angle in the presence of vibration modes and external disturbances. To obtain continues voltage as a control variable a smoothing integrator follows signum function in both channels. As a modification the switching governed by signum function is replaced by the high gain including rearrangement of the control system block diagram. The simulations indicate that the control system yields the desired robustness and further investigations are recommended.

  8. Robust Adaptive Sliding Mode Control for Generalized Function Projective Synchronization of Different Chaotic Systems with Unknown Parameters

    Directory of Open Access Journals (Sweden)

    Xiuchun Li

    2013-01-01

    Full Text Available When the parameters of both drive and response systems are all unknown, an adaptive sliding mode controller, strongly robust to exotic perturbations, is designed for realizing generalized function projective synchronization. Sliding mode surface is given and the controlled system is asymptotically stable on this surface with the passage of time. Based on the adaptation laws and Lyapunov stability theory, an adaptive sliding controller is designed to ensure the occurrence of the sliding motion. Finally, numerical simulations are presented to verify the effectiveness and robustness of the proposed method even when both drive and response systems are perturbed with external disturbances.

  9. Vision-based stabilization of nonholonomic mobile robots by integrating sliding-mode control and adaptive approach

    Science.gov (United States)

    Cao, Zhengcai; Yin, Longjie; Fu, Yili

    2013-01-01

    Vision-based pose stabilization of nonholonomic mobile robots has received extensive attention. At present, most of the solutions of the problem do not take the robot dynamics into account in the controller design, so that these controllers are difficult to realize satisfactory control in practical application. Besides, many of the approaches suffer from the initial speed and torque jump which are not practical in the real world. Considering the kinematics and dynamics, a two-stage visual controller for solving the stabilization problem of a mobile robot is presented, applying the integration of adaptive control, sliding-mode control, and neural dynamics. In the first stage, an adaptive kinematic stabilization controller utilized to generate the command of velocity is developed based on Lyapunov theory. In the second stage, adopting the sliding-mode control approach, a dynamic controller with a variable speed function used to reduce the chattering is designed, which is utilized to generate the command of torque to make the actual velocity of the mobile robot asymptotically reach the desired velocity. Furthermore, to handle the speed and torque jump problems, the neural dynamics model is integrated into the above mentioned controllers. The stability of the proposed control system is analyzed by using Lyapunov theory. Finally, the simulation of the control law is implemented in perturbed case, and the results show that the control scheme can solve the stabilization problem effectively. The proposed control law can solve the speed and torque jump problems, overcome external disturbances, and provide a new solution for the vision-based stabilization of the mobile robot.

  10. Stabilization of a Quadrotor With Uncertain Suspended Load Using Sliding Mode Control

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xu; Liu, Rui; Zhang, Jiucai; Zhang, Xiaoli

    2016-08-21

    The stability and trajectory control of a quadrotor carrying a suspended load with a fixed known mass has been extensively studied in recent years. However, the load mass is not always known beforehand in practical applications. This mass uncertainty brings uncertain disturbances to the quadrotor system, causing existing controllers to have a worse performance or to be collapsed. To improve the quadrotor's stability in this situation, we investigate the impacts of the uncertain load mass on the quadrotor. By comparing the simulation results of two controllers -- the proportional-derivative (PD) controller and the sliding mode controller (SMC) driven by a sliding mode disturbance of observer (SMDO), the quadrotor's performance is verified to be worse as the uncertainty increases. The simulation results also show a controller with stronger robustness against disturbances is better for practical applications.

  11. Stabilisasi Pada Sistem Pendulum-Kereta dengan Menggunakan Metode Fuzzy-Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Niora Fatimah Tanzania

    2014-03-01

    Full Text Available Sistem Pendulum-Kereta merupakan salah satu sistem nonlinear yang memiliki karakteristik sederhana namun sulit untuk dikontrol, sehingga sering digunakan untuk menguji berbagai metode kontrol. Pada Tugas Akhir ini membahas mengenai stabilisasi pada sistem pendulum-kereta dengan menggunakan metode Fuzzy-Sliding Mode Control agar sistem pendulum-kereta mampu mempertahankan batang pendulum dalam posisi terbaliknya dan tahan terhadap gangguan. Model nonlinear sistem pendulum-kereta akan direpresentasikan dalam model fuzzy Takagi-Sugeno untuk dua titik kerja. Dengan menggunakan model fuzzy Takagi-Sugeno tersebut, dipilih sebuah permukaan luncur. Terdapat dua sinyal kontrol pada Sliding Mode Control yaitu sinyal kontrol ekivalen yang memaksa state menuju permukaan luncur dan sinyal kontrol natural yang mempertahankan state dipermukaan luncur serta memberikan kekokohan sistem terhadap ketidakpastian. Gain pada sinyal kontrol ekivalen akan didesain dengan menggunakan Ackermanns Formula. Hasil simulasi dan implementasi menunjukkan bahwa batang pendulum dapat stabil pada posisi terbaliknya (0 radian dan mampu mengkompensasi gangguan yang terjadi pada sistem.

  12. Path following of an Underactuated AUV Based on Fuzzy Backstepping Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Xiao Liang

    2016-06-01

    Full Text Available This paper addresses the path following problem of an underactuated autonomous underwater vehicle (AUV with the aim of dealing with parameter uncertainties and current disturbances. An adaptive robust control system was proposed by employing fuzzy logic, backstepping and sliding mode control theory. Fuzzy logic theory is adopted to approximate unknown system function, and the controller was designed by combining sliding mode control with backstepping thought. Firstly, the longitudinal speed was controlled, then the yaw angle was made as input of path following error to design the calm function and the change rate of path parameters. The controller stability was proved by Lyapunov stable theory. Simulation and outfield tests were conducted and the results showed that the controller is of excellent adaptability and robustness in the presence of parameter uncertainties and external disturbances. It is also shown to be able to avoid the chattering of AUV actuators.

  13. Adaptive Fuzzy Sliding Mode Control for a Model-Scaled Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Amir Razzaghian

    2016-11-01

    Full Text Available This paper presents a novel Adaptive Fuzzy Sliding Mode Controller (AFSMC for a model-scaled unmanned helicopter as real nonlinear plant. First, in order to efficient control law design, the nonlinear model of the helicopter is reformulated as an affine nonlinear system. To do this aim, a Dynamic Inverter (DI is introduced as a bijective function. The proposed DI is used to interconnect the helicopter actuators' main inputs to the helicopter dynamic inputs. Then, AFSMC is designed to control it, and the asymptotic stability of the closed loop system is proved using Lyapunov stability theorem. To verify the merits of the proposed controller, it is compared with traditional sliding mode control system. Simulation results confirmed that the controller as a robust and stable control method has desired controlling performance and well cope with the undesirable chattering phenomenon.

  14. Discrete-time sliding mode control for MR vehicle suspension system

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, J W; Choi, S B [Smart Structures and Systems Laboratory, Department of Mechanical Engineering, Inha University, Incheon 402-751 (Korea, Republic of); Wereley, N M [Smart Structures Laboratory, Department of Aerospace Engineering, University of Maryland, College Park, MD 20742 (United States)], E-mail: seungbok@inha.ac.kr

    2009-02-01

    This paper presents control performance of a full-vehicle suspension system featuring magnetorheological (MR) dampers via a discrete-time sliding mode control algorithm (DSMC). A cylindrical MR damper is designed by incorporating Bingham model of the MR fluid and the field-dependent damping characteristics of the MR damper are evaluated. A full-vehicle suspension model installed with independent four MR dampers is constructed and the governing equations which include vertical, pitch and roll motion are derived. A discrete-time control model is established with considering system uncertainties and a discrete-time sliding mode controller which has inherent robustness to model uncertainty and external disturbance is formulated. Vibration control performances under bump excitation are evaluated and presented.

  15. Design of Sliding Mode Variable Structure Servo Driver Based on Hardware

    Directory of Open Access Journals (Sweden)

    Changfan Zhang

    2017-03-01

    Full Text Available Based on sliding mode control theory, in this paper a control method of tension control system in printing machine is presented. Firstly, a sliding mode controller for decreasing steady-state error is designed based on the servo motor model in the tension control system of printing machine, and the simulation verification is carried out in the MATLAB/Simulink. Further the hardware circuit is implemented through the design of operational amplifier to reduce the chattering of the system, and the trapezoidal wave is served as the input signal to reduce the overshoot of printing machine generated at the moment of start and stop, ensuring the smooth start and stop of the system. With the simulation results and the experimental results being consistent, it illustrates the correctness and practicality of the proposed method.

  16. Research of PMSM-DTC system based on the super-twisting second sliding mode control

    Directory of Open Access Journals (Sweden)

    Suying ZHANG

    2017-04-01

    Full Text Available Aiming at the problems that the conventional permanent magnet synchronous motor direct torque control system (PMSM-DTC is susceptible to the influence of parameter change and torque ripple, it is proposed that the space voltage vector modulation technique (SVPWM is used instead of the traditional sinusoidal pulse width modulation (SPWM, on the basis of which the second-order sliding mode variable structure control rate with super-twising algorithm is introduced, with the stator flux linkage and torque as the controlled object to design the controller instead of traditional PI controller in the system. The simulation results show that the strategy not only eliminates effectively the first-order sliding mode chattering problems, significantly reducing the stator flux linkage and torque ripple, but also has strong ability of speed tracking, with robustness to load disturbance, and parameter changes, etc., therefore can be well applied in motor control.

  17. Output feedback sliding mode control for a linear multi-compartment lung mechanics system

    Science.gov (United States)

    Hou, Saing Paul; Meskin, Nader; Haddad, Wassim M.

    2014-10-01

    In this paper, we develop a sliding mode control architecture to control lung volume and minute ventilation in the presence of modelling system uncertainties. Since the applied input pressure to the lungs is, in general, nonnegative and cannot be arbitrarily large, as not to damage the lungs, a sliding mode control with bounded nonnegative control inputs is proposed. The controller only uses output information (i.e., the total volume of the lungs) and automatically adjusts the applied input pressure so that the system is able to track a given reference signal in the presence of parameter uncertainty (i.e., modelling uncertainty of the lung resistances and lung compliances) and system disturbances. Controllers for both matched and unmatched uncertainties are presented. Specifically, a Lyapunov-based approach is presented for the stability analysis of the system and the proposed control framework is applied to a two-compartment lung model to show the efficacy of the proposed control method.

  18. Research of Compound Control for DC Motor System Based on Global Sliding Mode Disturbance Observer

    Directory of Open Access Journals (Sweden)

    He Zhang

    2014-01-01

    Full Text Available Aiming at the problems of modeling errors, parameter variations, and load moment disturbances in DC motor control system, one global sliding mode disturbance observer (GSMDO is proposed based on the global sliding mode (GSM control theory. The output of GSMDO is used as the disturbance compensation in control system, which can improve the robust performance of DC motor control system. Based on the designed GSMDO in inner loop, one compound controller, composed of a feedback controller and a feedforward controller, is proposed in order to realize the position tracking of DC motor system. The gains of feedback controller are obtained by means of linear quadratic regulator (LQR optimal control theory. Simulation results present that the proposed control scheme possesses better tracking properties and stronger robustness against modeling errors, parameter variations, and friction moment disturbances. Moreover, its structure is simple; therefore it is easy to be implemented in engineering.

  19. Chattering-Free Sliding-Mode Control for Electromechanical Actuator with Backlash Nonlinearity

    Directory of Open Access Journals (Sweden)

    Dongqi Ma

    2017-01-01

    Full Text Available Considering the backlash nonlinearity and parameter time-varying characteristics in electromechanical actuators, a chattering-free sliding-mode control strategy is proposed in this paper to regulate the rudder angle and suppress unknown external disturbances. Different from most existing backlash compensation methods, a special continuous function is addressed to approximate the backlash nonlinear dead-zone model. Regarding the approximation error, unmodeled dynamics, and unknown external disturbances as a disturbance-like term, a strict feedback nonlinear model is established. Based on this nonlinear model, a chattering-free nonsingular terminal sliding-mode controller is proposed to achieve the rudder angle tracking with a chattering elimination and tracking dynamic performance improvement. A Lyapunov-based proof ensures the asymptotic stability and finite-time convergence of the closed-loop system. Experimental results have verified the effectiveness of the proposed method.

  20. Design and Comparison of AFS Controllers with PID, Fuzzy-Logic, and Sliding-Mode Controllers

    Directory of Open Access Journals (Sweden)

    Jeonghoon Song

    2013-01-01

    Full Text Available Three active front-steering (AFS controllers were developed to enhance the lateral stability of a vehicle. They were designed using proportional-integral-derivative (PID, fuzzy-logic, and sliding-mode control methods. The controllers were compared under several driving and road conditions with and without the application of braking force. A 14-degree-of-freedom vehicle model, a sliding-mode antilock brake system (ABS controller, and a driver model were also employed to test the controllers. The results show that the three AFS controllers allowed the yaw rate to follow the reference yaw rate very well, and consequently the lateral stability improved. On a split-μ road, the controllers forced the vehicle to proceed straight ahead. The results also verify that the driver model can sufficiently control the vehicle to allow it to follow a desired path.

  1. Fault Tolerant Flight Control Using Sliding Modes and Subspace Identification-Based Predictive Control

    KAUST Repository

    Siddiqui, Bilal A.

    2016-07-26

    In this work, a cascade structure of a time-scale separated integral sliding mode and model predictive control is proposed as a viable alternative for fault-tolerant control. A multi-variable sliding mode control law is designed as the inner loop of the flight control system. Subspace identification is carried out on the aircraft in closed loop. The identified plant is then used for model predictive controllers in the outer loop. The overall control law demonstrates improved robustness to measurement noise, modeling uncertainties, multiple faults and severe wind turbulence and gusts. In addition, the flight control system employs filters and dead-zone nonlinear elements to reduce chattering and improve handling quality. Simulation results demonstrate the efficiency of the proposed controller using conventional fighter aircraft without control redundancy.

  2. Implementation of fuzzy-sliding mode based control of a grid connected photovoltaic system.

    Science.gov (United States)

    Menadi, Abdelkrim; Abdeddaim, Sabrina; Ghamri, Ahmed; Betka, Achour

    2015-09-01

    The present work describes an optimal operation of a small scale photovoltaic system connected to a micro-grid, based on both sliding mode and fuzzy logic control. Real time implementation is done through a dSPACE 1104 single board, controlling a boost chopper on the PV array side and a voltage source inverter (VSI) on the grid side. The sliding mode controller tracks permanently the maximum power of the PV array regardless of atmospheric condition variations, while The fuzzy logic controller (FLC) regulates the DC-link voltage, and ensures via current control of the VSI a quasi-total transit of the extracted PV power to the grid under a unity power factor operation. Simulation results, carried out via Matlab-Simulink package were approved through experiment, showing the effectiveness of the proposed control techniques. Copyright © 2015. Published by Elsevier Ltd.

  3. Extended observer based on adaptive second order sliding mode control for a fixed wing UAV.

    Science.gov (United States)

    Castañeda, Herman; Salas-Peña, Oscar S; León-Morales, Jesús de

    2017-01-01

    This paper addresses the design of attitude and airspeed controllers for a fixed wing unmanned aerial vehicle. An adaptive second order sliding mode control is proposed for improving performance under different operating conditions and is robust in presence of external disturbances. Moreover, this control does not require the knowledge of disturbance bounds and avoids overestimation of the control gains. Furthermore, in order to implement this controller, an extended observer is designed to estimate unmeasurable states as well as external disturbances. Additionally, sufficient conditions are given to guarantee the closed-loop stability of the observer based control. Finally, using a full 6 degree of freedom model, simulation results are obtained where the performance of the proposed method is compared against active disturbance rejection based on sliding mode control. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Processing Sliding Mosaic Mode Data with Modified Full-Aperture Imaging Algorithm Integrating Scalloping Correction

    Directory of Open Access Journals (Sweden)

    Zhao Tuan

    2016-10-01

    Full Text Available In this study, we present a modified full-aperture imaging algorithm that includes scalloping correction and spike suppression for sliding-Mosaic-mode Synthetic Aperture Radar (SAR. It is innovational to correct the azimuth beam-pattern weighting altered by radar antenna rotation in the azimuth during the deramping preprocessing operation. The main idea of spike suppression is to substitute zeros between bursts with linear-predicted data extrapolated from adjacent bursts to suppress spikes caused by multiburst processing. We also integrate scalloping correction for the sliding mode into this algorithm. Finally, experiments are performed using the C-band airborne SAR system with a maximum bandwidth of 200 MHz to validate the effectiveness of this approach.

  5. High-order sliding mode control for sensorless trajectory tracking of a PMSM

    Science.gov (United States)

    Delpoux, R.; Floquet, T.

    2014-10-01

    The paper presents a new sensorless approach for permanent magnet synchronous motor. Current sensors are assumed available, but position and velocity sensors are not. Based on the electrical equations, sliding mode observers are designed to estimate the back-electro motive force (EMF) of the motor. These estimations are used to reconstruct the position and the velocity. From this estimation, a robust sliding mode control is developed which ensures the position tracking of the motor. A new reference frame is used that presents advantages similar to the standard (d - q) frame, but without the need for a position sensor. The efficiency of the algorithm is shown through experimental results. The approach is potentially applicable to other types of synchronous motors as well.

  6. Robust Synchronization of Incommensurate Fractional-Order Chaotic Systems via Second-Order Sliding Mode Technique

    Directory of Open Access Journals (Sweden)

    Hua Chen

    2013-01-01

    Full Text Available A second-order sliding mode (SOSM controller is proposed to synchronize a class of incommensurate fractional-order chaotic systems with model uncertainties and external disturbances. Based on the chattering free SOSM control scheme, it can be rigorously proved that the dynamics of the synchronization error is globally asymptotically stable by using the Lyapunov stability theorem. Finally, numerical examples are provided to illustrate the effectiveness of the proposed controller design approach.

  7. On sliding mode observer for a hybrid three-cell converter

    KAUST Repository

    Khelouat, Samir

    2013-10-01

    In this paper, we propose a sliding mode observer to estimate the capacitor voltages of the 3-cell converter. New concept recently introduced, based on geometrical condition for observability analysis is used. The convergence of estimation error based on the solution of an LMI system is shown. Finally, illustrative results are given in order to show the efficiency of the designed observer. © 2013 IEEE.

  8. Finite-time integral sliding mode control for chaotic permanent magnet synchronous motor systems

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    Chibani Abdelilah

    2017-06-01

    Full Text Available In this paper, an integral finite-time sliding mode control scheme is presented for controlling a chaotic permanent magnet synchronous motor (PMSM. The controller can stabilize the system output tracking error to zero in a finite time. Using Lyapunov’s stability theory, the stability of the proposed scheme is verified. Numerical simulation results are presented to present the effectiveness of the proposed approach.

  9. Quasi-Sliding Mode Control of Chaos in Permanent Magnet Synchronous Motor

    Directory of Open Access Journals (Sweden)

    Cheng-Fang Huang

    2011-01-01

    Full Text Available A quasi-sliding mode control (QSMC to suppress chaos for a permanent magnet synchronous motor (PMSM with parameters fall into a certain area is proposed in this paper. Especially, based on the new concept of QSMC, continuous control input is obtained to avoid chattering phenomenon. As expected, the system states can be driven to zero or into a predictable and adjustable bound even when uncertainties are present. Numerical simulations demonstrate the validity of the proposed QSMC design method.

  10. Chattering-Free Adaptive Sliding Mode Control for Attitude Tracking of Spacecraft with External Disturbance

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    Xuxi Zhang

    2014-01-01

    Full Text Available The attitude tracking problem of spacecraft in the presence of unknown disturbance is investigated. By using the adaptive control technique and the Lyapunov stability theory, a chattering-free adaptive sliding mode control law is proposed for the attitude tracking problem of spacecraft with unknown disturbance. Simulation results are employed to demonstrate the effectiveness of the proposed control design technique in this paper.

  11. Control and fault diagnosis based sliding mode observer of a multicellular converter: Hybrid approach

    KAUST Repository

    Benzineb, Omar

    2013-01-01

    In this article, the diagnosis of a three cell converter is developed. The hybrid nature of the system represented by the presence of continuous and discrete dynamics is taken into account in the control design. The idea is based on using a hybrid control and an observer-type sliding mode to generate residuals from the observation errors of the system. The simulation results are presented at the end to illustrate the performance of the proposed approach. © 2013 FEI STU.

  12. Sensorless Vector Control of AC Induction Motor Using Sliding-Mode Observer

    Directory of Open Access Journals (Sweden)

    Phuc Thinh Doan

    2013-06-01

    Full Text Available This paper develops a sensorless vector controlled method for AC induction motor using sliding-mode observer. For developing the control algorithm, modeling of AC induction motor is presented. After that, a sliding mode observer is proposed to estimate the motor speed, the rotor flux, the angular position of the rotor flux and the motor torque from monitored stator voltages and currents. The use of the nonlinear sliding mode observer provides very good performance for both low and high speed motor operation. Furthermore, the proposed system is robust in motor losses and load variations. The convergence of the proposed observer is obtained using the Lyapunov theory. Hardware and software for simulation and experiment of the AC induction motor drive are introduced. The hardware consists of a 1.5kw AC induction motor connected in series with a torque sensor and a powder brake. A controller is developed based on DSP TMS320F28355. The simulation and experimental results illustrate that fast torque and speed response with small torque ripples can be achieved. The proposed control scheme is suitable to the application fields that require high performance of torque response such as electric vehicles. doi:http://dx.doi.org/10.12777/ijse.4.2.2013.39-43 [How to cite this article: Doan, P. T., Nguyen, T. T., Jeong, S. K., Oh, S. J., & Kim, S. B. (2013. Sensorless Vector Control of AC Induction Motor Using Sliding-Mode Observer. INTERNATIONAL JOURNAL OF SCIENCE AND ENGINEERING, 4(2, 39-43; doi: http://dx.doi.org/10.12777/ijse.4.2.2013.39-43

  13. Dynamic modeling and Super-Twisting Sliding Mode Control for Tethered Space Robot

    Science.gov (United States)

    Zhao, Yakun; Huang, Panfeng; Zhang, Fan

    2018-02-01

    Recent years, tethered space capturing systems have been considered as one of the most promising solutions for active space debris removal due to the increasing threat of space debris to spacecraft and astronauts. In this paper, one of the tethered space capturing systems, Tethered Space Robot (TSR), is investigated. TSR includes a space platform, a space tether, and a gripper as the terminal device. Based on the assumptions that the platform and the gripper are point masses and the tether is rigid, inextensible and remaining straight, the dynamic model of TSR is presented, in which the disturbances from space environment is considered. According to the previous study, the in-plane and out-of-plane angles of the tether oscillate periodically although the tether is released to the desired length. A super-twisting adaptive sliding mode control scheme is designed for TSR to eliminate the vibration of the tether to assure a successful capture in station-keeping phase. Both uncontrolled and controlled situations are simulated. The simulation results show that the proposed controller is effective. Additionally, after comparing with normal sliding mode control algorithm, it is verified that the proposed control scheme can avoid the chattering of normal sliding mode control and is robust for unknown boundary perturbations.

  14. Current Sensor Fault Diagnosis Based on a Sliding Mode Observer for PMSM Driven Systems.

    Science.gov (United States)

    Huang, Gang; Luo, Yi-Ping; Zhang, Chang-Fan; Huang, Yi-Shan; Zhao, Kai-Hui

    2015-05-11

    This paper proposes a current sensor fault detection method based on a sliding mode observer for the torque closed-loop control system of interior permanent magnet synchronous motors. First, a sliding mode observer based on the extended flux linkage is built to simplify the motor model, which effectively eliminates the phenomenon of salient poles and the dependence on the direct axis inductance parameter, and can also be used for real-time calculation of feedback torque. Then a sliding mode current observer is constructed in αβ coordinates to generate the fault residuals of the phase current sensors. The method can accurately identify abrupt gain faults and slow-variation offset faults in real time in faulty sensors, and the generated residuals of the designed fault detection system are not affected by the unknown input, the structure of the observer, and the theoretical derivation and the stability proof process are concise and simple. The RT-LAB real-time simulation is used to build a simulation model of the hardware in the loop. The simulation and experimental results demonstrate the feasibility and effectiveness of the proposed method.

  15. Flight Control Design for an Autonomous Rotorcraft Using Pseudo-Sliding Mode Control and Waypoint Navigation

    Science.gov (United States)

    Mallory, Nicolas Joseph

    The design of robust automated flight control systems for aircraft of varying size and complexity is a topic of continuing interest for both military and civilian industries. By merging the benefits of robustness from sliding mode control (SMC) with the familiarity and transparency of design tradeoff offered by frequency domain approaches, this thesis presents pseudo-sliding mode control as a viable option for designing automated flight control systems for complex six degree-of-freedom aircraft. The infinite frequency control switching of SMC is replaced, by necessity, with control inputs that are continuous in nature. An introduction to SMC theory is presented, followed by a detailed design of a pseudo-sliding mode control and automated flight control system for a six degree-of-freedom model of a Hughes OH6 helicopter. This model is then controlled through three different waypoint missions that demonstrate the stability of the system and the aircraft's ability to follow certain maneuvers despite time delays, large changes in model parameters and vehicle dynamics, actuator dynamics, sensor noise, and atmospheric disturbances.

  16. A New Sliding Mode Controller for DC/DC Converters in Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    M. Sarvi

    2013-01-01

    Full Text Available DC/DC converters are widely used in many industrial and electrical systems. As DC/DC converters are nonlinear and time-variant systems, the application of linear control techniques for the control of these converters is not suitable. In this paper, a new sliding mode controller is proposed as the indirect control method and compared to a simple direct control method in order to control a buck converter in photovoltaic applications. The solar arrays are dependent power sources with nonlinear voltage-current characteristics under different environmental conditions (insolation and temperature. From this point of view, the DC/DC converter is particularly suitable for the application of the sliding mode control in photovoltaic application, because of its controllable states. Simulations are performed in Matlab/Simulink software. The simulation results are presented for a step change in reference voltage and input voltage as well as step load variations. The simulations results of proposed method are compared with the conventional PID controller. The results show the good performance of the proposed sliding mode controller. The proposed method can be used for the other DC/DC converter.

  17. Sliding Mode Control of Fractional-Order Delayed Memristive Chaotic System with Uncertainty and Disturbance

    Science.gov (United States)

    Ding, Da-Wei; Liu, Fang-Fang; Chen, Hui; Wang, Nian; Liang, Dong

    2017-12-01

    In this paper, a simplest fractional-order delayed memristive chaotic system is proposed in order to control the chaos behaviors via sliding mode control strategy. Firstly, we design a sliding mode control strategy for the fractional-order system with time delay to make the states of the system asymptotically stable. Then, we obtain theoretical analysis results of the control method using Lyapunov stability theorem which guarantees the asymptotic stability of the non-commensurate order and commensurate order system with and without uncertainty and an external disturbance. Finally, numerical simulations are given to verify that the proposed sliding mode control method can eliminate chaos and stabilize the fractional-order delayed memristive system in a finite time. Supported by the National Nature Science Foundation of China under Grant No. 61201227, Funding of China Scholarship Council, the Natural Science Foundation of Anhui Province under Grant No. 1208085M F93, 211 Innovation Team of Anhui University under Grant Nos. KJTD007A and KJTD001B

  18. Fuzzy Sliding Mode Lateral Control of Intelligent Vehicle Based on Vision

    Directory of Open Access Journals (Sweden)

    Linhui Li

    2013-01-01

    Full Text Available The lateral control of intelligent vehicle is studied in this paper, with the intelligent vehicle DLUIV-1 based on visual navigation as the object of research. Firstly, the lateral control model based on visual preview is established. The kinematics model based on visual preview, including speed and other factors, is used to calculate the lateral error and direction error. Secondly, according to the characteristics of lateral control, an efficient strategy of intelligent vehicle lateral mode is proposed. The integration of the vehicle current lateral error and direction error is chosen as the parameter of the sliding mode switching function to design the sliding surface. The control variables are adjusted according to the fuzzy control rules to ensure that they meet the existence and reaching condition. The sliding mode switching function is regarded as the control objective, to ensure the stability of the steering wheel rotation. Simulation results show that the lateral controller can guarantee high path-tracking accuracy and strong robustness for the change of model parameters.

  19. Nonlinear adaptive control based on fuzzy sliding mode technique and fuzzy-based compensator.

    Science.gov (United States)

    Nguyen, Sy Dzung; Vo, Hoang Duy; Seo, Tae-Il

    2017-09-01

    It is difficult to efficiently control nonlinear systems in the presence of uncertainty and disturbance (UAD). One of the main reasons derives from the negative impact of the unknown features of UAD as well as the response delay of the control system on the accuracy rate in the real time of the control signal. In order to deal with this, we propose a new controller named CO-FSMC for a class of nonlinear control systems subjected to UAD, which is constituted of a fuzzy sliding mode controller (FSMC) and a fuzzy-based compensator (CO). Firstly, the FSMC and CO are designed independently, and then an adaptive fuzzy structure is discovered to combine them. Solutions for avoiding the singular cases of the fuzzy-based function approximation and reducing the calculating cost are proposed. Based on the solutions, fuzzy sliding mode technique, lumped disturbance observer and Lyapunov stability analysis, a closed-loop adaptive control law is formulated. Simulations along with a real application based on a semi-active train-car suspension are performed to fully evaluate the method. The obtained results reflected that vibration of the chassis mass is insensitive to UAD. Compared with the other fuzzy sliding mode control strategies, the CO-FSMC can provide the best control ability to reduce unwanted vibrations. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  20. Robust current control-based generalized predictive control with sliding mode disturbance compensation for PMSM drives.

    Science.gov (United States)

    Liu, Xudong; Zhang, Chenghui; Li, Ke; Zhang, Qi

    2017-11-01

    This paper addresses the current control of permanent magnet synchronous motor (PMSM) for electric drives with model uncertainties and disturbances. A generalized predictive current control method combined with sliding mode disturbance compensation is proposed to satisfy the requirement of fast response and strong robustness. Firstly, according to the generalized predictive control (GPC) theory based on the continuous time model, a predictive current control method is presented without considering the disturbance, which is convenient to be realized in the digital controller. In fact, it's difficult to derive the exact motor model and parameters in the practical system. Thus, a sliding mode disturbance compensation controller is studied to improve the adaptiveness and robustness of the control system. The designed controller attempts to combine the merits of both predictive control and sliding mode control, meanwhile, the controller parameters are easy to be adjusted. Lastly, the proposed controller is tested on an interior PMSM by simulation and experiment, and the results indicate that it has good performance in both current tracking and disturbance rejection. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Integral sliding mode-based formation control of multiple unertain robots via nonlinear disturbane observer

    Directory of Open Access Journals (Sweden)

    Dianwei Qian

    2016-11-01

    Full Text Available This article proposes a control scheme for formation of maneuvers of a team of mobile robots. The control scheme integrates the integral sliding mode control method with the nonlinear disturbance observer technique. The leader–follower formation dynamics suffer from uncertainties originated from the individual robots. The uncertainties challenge the formation control of such robots. Assuming that the uncertainties are unknown but bounded, an nonlinear disturbance observer-based observer is utilized to approximate them. The observer outputs feed on an integral sliding mode control-based controller. The controller and observer are integrated into the control scheme to realize formation maneuvers despite uncertainties. The formation stability is analyzed by means of the Lyapunov’s theorem. In the sense of Lyapunov, not only the convergence of the approximation errors is guaranteed but also such a control scheme can asymptotically stabilize the formation system. Compared to the results by the sole integral sliding mode control, some simulations are presented to demonstrate the feasibility and performance of the control scheme.

  2. Robust stabilization and synchronization of a class of fractional-order chaotic systems via a novel fractional sliding mode controller

    Science.gov (United States)

    Aghababa, Mohammad Pourmahmood

    2012-06-01

    This paper proposes a novel fractional-order sliding mode approach for stabilization and synchronization of a class of fractional-order chaotic systems. Based on the fractional calculus a stable integral type fractional-order sliding surface is introduced. Using the fractional Lyapunov stability theorem, a single sliding mode control law is proposed to ensure the existence of the sliding motion in finite time. The proposed control scheme is applied to stabilize/synchronize a class of fractional-order chaotic systems in the presence of model uncertainties and external disturbances. Some numerical simulations are performed to confirm the theoretical results of the paper. It is worth noticing that the proposed fractional-order sliding mode controller can be applied to control a broad range of fractional-order dynamical systems.

  3. A neuro-sliding-mode control with adaptive modeling of uncertainty for control of movement in paralyzed limbs using functional electrical stimulation.

    Science.gov (United States)

    Ajoudani, Arash; Erfanian, Abbas

    2009-07-01

    During the past several years, several strategies have been proposed for control of joint movement in paraplegic subjects using functional electrical stimulation (FES), but developing a control strategy that provides satisfactory tracking performance, to be robust against time-varying properties of muscle-joint dynamics, day-to-day variations, subject-to-subject variations, muscle fatigue, and external disturbances, and to be easy to apply without any re-identification of plant dynamics during different experiment sessions is still an open problem. In this paper, we propose a novel control methodology that is based on synergistic combination of neural networks with sliding-mode control (SMC) for controlling FES. The main advantage of SMC derives from the property of robustness to system uncertainties and external disturbances. However, the main drawback of the standard sliding modes is mostly related to the so-called chattering caused by the high-frequency control switching. To eliminate the chattering, we couple two neural networks with online learning without any offline training into the SMC. A recurrent neural network is used to model the uncertainties and provide an auxiliary equivalent control to keep the uncertainties to low values, and consequently, to use an SMC with lower switching gain. The second neural network consists of a single neuron and is used as an auxiliary controller. The control law will be switched from the SMC to neural control, when the state trajectory of system enters in some boundary layer around the sliding surface. Extensive simulations and experiments on healthy and paraplegic subjects are provided to demonstrate the robustness, stability, and tracking accuracy of the proposed neuroadaptive SMC. The results show that the neuro-SMC provides accurate tracking control with fast convergence for different reference trajectories and could generate control signals to compensate the muscle fatigue and reject the external disturbance.

  4. Sliding-mode control of single input multiple output DC-DC converter

    Science.gov (United States)

    Zhang, Libo; Sun, Yihan; Luo, Tiejian; Wan, Qiyang

    2016-10-01

    Various voltage levels are required in the vehicle mounted power system. A conventional solution is to utilize an independent multiple output DC-DC converter whose cost is high and control scheme is complicated. In this paper, we design a novel SIMO DC-DC converter with sliding mode controller. The proposed converter can boost the voltage of a low-voltage input power source to a controllable high-voltage DC bus and middle-voltage output terminals, which endow the converter with characteristics of simple structure, low cost, and convenient control. In addition, the sliding mode control (SMC) technique applied in our converter can enhance the performances of a certain SIMO DC-DC converter topology. The high-voltage DC bus can be regarded as the main power source to the high-voltage facility of the vehicle mounted power system, and the middle-voltage output terminals can supply power to the low-voltage equipment on an automobile. In the respect of control algorithm, it is the first time to propose the SMC-PID (Proportion Integration Differentiation) control algorithm, in which the SMC algorithm is utilized and the PID control is attended to the conventional SMC algorithm. The PID control increases the dynamic ability of the SMC algorithm by establishing the corresponding SMC surface and introducing the attached integral of voltage error, which endow the sliding-control system with excellent dynamic performance. At last, we established the MATLAB/SIMULINK simulation model, tested performance of the system, and built the hardware prototype based on Digital Signal Processor (DSP). Results show that the sliding mode control is able to track a required trajectory, which has robustness against the uncertainties and disturbances.

  5. Adaptive PI-Based Sliding Mode Control for Nanopositioning of Piezoelectric Actuators

    Directory of Open Access Journals (Sweden)

    Jin Li

    2014-01-01

    Full Text Available This paper proposes an adaptive proportion-integral (PI-based sliding mode control design (APISMC used for nanopositioning of piezoelectric actuators (PEAs. Nonlinearities, mainly hysteresis, can drastically degrade the system performance. As well as the model imperfection, hysteresis can be treated as uncertainties of the system. These uncertainties can be addressed by sliding mode control (SMC since SMC is promising for positioning and tracking control. To further improve the response speed, suppress chattering, and reduce the steady-state error, the adaptive PI-based SMC is employed to replace the discontinuous control. Actually, the adaptive PI-based SMC offers a fast convergence of the sliding surface. Further, another advantage of the proposed controller lies in that its implementation only requires the online tuning PI parameters without acquiring the knowledge of bounds on system uncertainties. A linear second-order system is utilized as the estimated model to compensate for the process nonlinearity and estimate the control gain. The robust stability of the APISMC is proved through a Lyapunov stability analysis. Simulation results demonstrate that the modified SMC is superior to the original one for both positioning and tracking applications. Compared with the original, the proposed controller provides better performance—less chattering, faster response, and higher precision.

  6. Robust adaptive multivariable higher-order sliding mode flight control for air-breathing hypersonic vehicle with actuator failures

    Directory of Open Access Journals (Sweden)

    Peng Li

    2016-10-01

    Full Text Available This article proposes an adaptive multivariable higher-order sliding mode control for the longitudinal model of an air-breathing vehicle under system uncertainties and actuator failures. Firstly, a fast finite-time control law is designed for a chain of integrators. Secondly, based on the input/output feedback linearization technique, the system uncertainty and external disturbances are modeled as additive certainty and the actuator failures are modeled as multiplicative uncertainty. By using the proposed fast finite-time control law, a robust multivariable higher-order sliding mode control is designed for the air-breathing hypersonic vehicle with actuator failures. Finally, adaptive laws are proposed for the adaptation of the parameters in the robust multivariable higher-order sliding mode control. Thus, the bounds of the uncertainties are not needed in the control system design. Simulation results show the effectiveness of the proposed robust adaptive multivariable higher-order sliding mode control.

  7. A new method to minimize the chattering phenomenon in sliding mode control based on intelligent control for induction motor drives

    Directory of Open Access Journals (Sweden)

    Bendaas Ismail

    2013-01-01

    Full Text Available This paper presents new method toward the design of hybrid control with sliding-mode (SMC plus fuzzy logic control (FLC for induction motors. As the variations of both control system parameters and operating conditions occur, the conventional control methods may not be satisfied further. Sliding mode control is robust with respect to both induction motor parameter variations and external disturbances. By embedding a fuzzy logic control into the sliding mode control, the chattering (torque-ripple problem with varying parameters, which are the main disadvantage in sliding-mode control, can be suppressed, Simulation results of the proposed control theme present good dynamic and steady-state performances as compared to the classical SMC from aspects for torque-ripple minimization, the quick dynamic torque response and robustness to disturbance and variation of parameters.

  8. Sliding Mode Control of DFIG Wind Turbines with a Fast Exponential Reaching Law

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    Linyun Xiong

    2017-11-01

    Full Text Available This paper proposes a novel sliding mode control (SMC technique for doubly fed induction generators (DFIGs based on the fast exponential reaching law (FERL. The proposed FERL-based SMC is capable of reducing to a large extent the chattering phenomena existing in the sliding stage. Meanwhile, the reaching stage is accelerated with the introduction of an adaptive gain. The proposed method is employed in a DFIG-based wind energy conversion system (WECS for direct power control (DPC. The FERL-based DPC approach is tested with simulations conducted in Matlab/Simulink under the scenarios of unbalanced grid voltage, grid fault conditions and highly unstable wind speed accompanied by an experimental study. The simulations and experimental results reveal the better performance of the proposed control method in active/reactive power tracking and dc-link voltage maintenance.

  9. Variable speed wind turbine control by discrete-time sliding mode approach.

    Science.gov (United States)

    Torchani, Borhen; Sellami, Anis; Garcia, Germain

    2016-05-01

    The aim of this paper is to propose a new design variable speed wind turbine control by discrete-time sliding mode approach. This methodology is designed for linear saturated system. The saturation constraint is reported on inputs vector. To this end, the back stepping design procedure is followed to construct a suitable sliding manifold that guarantees the attainment of a stabilization control objective. It is well known that the mechanisms are investigated in term of the most proposed assumptions to deal with the damping, shaft stiffness and inertia effect of the gear. The objectives are to synthesize robust controllers that maximize the energy extracted from wind, while reducing mechanical loads and rotor speed tracking combined with an electromagnetic torque. Simulation results of the proposed scheme are presented. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  10. MIMO Sliding Mode Control for a Tailless Fighter Aircraft, An Alternative to Reconfigurable Architectures

    Science.gov (United States)

    Wells, S. R.; Hess, R. A.

    2002-01-01

    A frequency-domain procedure for the design of sliding mode controllers for multi-input, multi-output (MIMO) systems is presented. The methodology accommodates the effects of parasitic dynamics such as those introduced by unmodeled actuators through the introduction of multiple asymptotic observers and model reference hedging. The design procedure includes a frequency domain approach to specify the sliding manifold, the observer eigenvalues, and the hedge model. The procedure is applied to the development of a flight control system for a linear model of the Innovative Control Effector (ICE) fighter aircraft. The stability and performance robustness of the resulting design is demonstrated through the introduction of significant degradation in the control effector actuators and variation in vehicle dynamics.

  11. Generalized projective synchronization of the fractional-order chaotic system using adaptive fuzzy sliding mode control

    Science.gov (United States)

    Wang, Li-Ming; Tang, Yong-Guang; Chai, Yong-Quan; Wu, Feng

    2014-10-01

    An adaptive fuzzy sliding mode strategy is developed for the generalized projective synchronization of a fractional-order chaotic system, where the slave system is not necessarily known in advance. Based on the designed adaptive update laws and the linear feedback method, the adaptive fuzzy sliding controllers are proposed via the fuzzy design, and the strength of the designed controllers can be adaptively adjusted according to the external disturbances. Based on the Lyapunov stability theorem, the stability and the robustness of the controlled system are proved theoretically. Numerical simulations further support the theoretical results of the paper and demonstrate the efficiency of the proposed method. Moreover, it is revealed that the proposed method allows us to manipulate arbitrarily the response dynamics of the slave system by adjusting the desired scaling factor λi and the desired translating factor ηi, which may be used in a channel-independent chaotic secure communication.

  12. Analysis of an ACC System for Sliding Mode and MPC under Transitional Manoeuvers

    Directory of Open Access Journals (Sweden)

    Zeeshan Ali Memon

    2012-10-01

    Full Text Available Two different control algorithms, sliding mode and MPC (Model Predictive Control are employed to analyse the performance of a linear vehicle model equipped with an ACC (Adaptive Cruise Control system. Both controllers are analysed under critical TM (Transitional Maneuvers to investigate their suitability for the ACC system. The simulation results, for the same scenario, from both controllers\\' approach have been compared. The results show that the MPC is more robust than the SMC (Sliding Model Controller. The results show that the SMC algorithm is not suitable for the proposed vehicle model. The shortcomings of the SMC have been highlighted and the comparisons are made with the previous studies. The proposed approach can be useful for the selection of the appropriate controller for the given application.

  13. Design and Analysis of Sliding Mode Controller and Simplified Space Vector Modulation for Three Phase Shunt Active Power Filter

    OpenAIRE

    Elangovan, S; K. Thanushkodi; P. N. Neelakantan

    2014-01-01

    The main aim of this study is to control a multivariable coupled system by choosing sliding mode switching function. A Sliding mode control approach is developed to control a three phase three wire voltage source inverter operating as a shunt active power filter. Hence, no need to divide the system model developed in the synchronous ‘dq’ reference frame into two separate loops. Furthermore, the proposed control strategy allows a better stability and robustness over a wide range of operation. ...

  14. Synchronization for a Class of Uncertain Fractional Order Chaotic Systems with Unknown Parameters Using a Robust Adaptive Sliding Mode Controller

    Directory of Open Access Journals (Sweden)

    Yan Yan

    2016-01-01

    Full Text Available This paper deals with the synchronization of a class of fractional order chaotic systems with unknown parameters and external disturbance. Based on the Lyapunov stability theory, a fractional order sliding mode is constructed and a controller is proposed to realize chaos synchronization. The presented method not only realizes the synchronization of the considered chaotic systems but also enhances the robustness of sliding mode synchronization. Finally, some simulation results demonstrate the effectiveness and robustness of the proposed method.

  15. Second-order sliding mode control for DFIG-based wind turbines fault ride-through capability enhancement.

    Science.gov (United States)

    Benbouzid, Mohamed; Beltran, Brice; Amirat, Yassine; Yao, Gang; Han, Jingang; Mangel, Hervé

    2014-05-01

    This paper deals with the fault ride-through capability assessment of a doubly fed induction generator-based wind turbine using a high-order sliding mode control. Indeed, it has been recently suggested that sliding mode control is a solution of choice to the fault ride-through problem. In this context, this paper proposes a second-order sliding mode as an improved solution that handle the classical sliding mode chattering problem. Indeed, the main and attractive features of high-order sliding modes are robustness against external disturbances, the grids faults in particular, and chattering-free behavior (no extra mechanical stress on the wind turbine drive train). Simulations using the NREL FAST code on a 1.5-MW wind turbine are carried out to evaluate ride-through performance of the proposed high-order sliding mode control strategy in case of grid frequency variations and unbalanced voltage sags. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Synchronization of uncertain fractional-order chaotic systems with disturbance based on a fractional terminal sliding mode controller

    Science.gov (United States)

    Wang, Dong-Feng; Zhang, Jin-Ying; Wang, Xiao-Yan

    2013-04-01

    This paper provides a novel method to synchronize uncertain fractional-order chaotic systems with external disturbance via fractional terminal sliding mode control. Based on Lyapunov stability theory, a new fractional-order switching manifold is proposed, and in order to ensure the occurrence of sliding motion in finite time, a corresponding sliding mode control law is designed. The proposed control scheme is applied to synchronize the fractional-order Lorenz chaotic system and fractional-order Chen chaotic system with uncertainty and external disturbance parameters. The simulation results show the applicability and efficiency of the proposed scheme.

  17. Control of Chaos in Rate-Dependent Friction-Induced Vibration Using Adaptive Sliding Mode Control and Impulse Damper

    Directory of Open Access Journals (Sweden)

    Ehsan Maani Miandoab

    2013-01-01

    Full Text Available Two different control methods, namely, adaptive sliding mode control and impulse damper, are used to control the chaotic vibration of a block on a belt system due to the rate-dependent friction. In the first method, using the sliding mode control technique and based on the Lyapunov stability theory, a sliding surface is determined, and an adaptive control law is established which stabilizes the chaotic response of the system. In the second control method, the vibration of this system is controlled by an impulse damper. In this method, an impulsive force is applied to the system by expanding and contracting the PZT stack according to efficient control law. Numerical simulations demonstrate the effectiveness of both methods in controlling the chaotic vibration of the system. It is shown that the settling time of the controlled system using impulse damper is less than that one controlled by adaptive sliding mode control; however, it needs more control effort.

  18. Attitude Analysis and Robust Adaptive Backstepping Sliding Mode Control of Spacecrafts Orbiting Irregular Asteroids

    Directory of Open Access Journals (Sweden)

    Chunhui Liang

    2014-01-01

    Full Text Available Attitude stability analysis and robust control algorithms for spacecrafts orbiting irregular asteroids are investigated in the presence of model uncertainties and external disturbances. Rigid spacecraft nonlinear attitude models are considered and detailed attitude stability analysis of spacecraft subjected to the gravity gradient torque in an irregular central gravity field is included in retrograde orbits and direct orbits using linearized system model. The robust adaptive backstepping sliding mode control laws are designed to make the attitude of the spacecrafts stabilized and responded accurately to the expectation in the presence of disturbances and parametric uncertainties. Numerical simulations are included to illustrate the spacecraft performance obtained using the proposed control laws.

  19. A Class of Speed Sensorless Sliding Mode Observers for Direct Torque Controlled Induction Motor Drives

    DEFF Research Database (Denmark)

    Lascu, Cristian; Boldea, Ion; Blaabjerg, Frede

    2004-01-01

    A family of speed-sensorless sliding-mode observers for induction motors has been developed. Three topologies have been investigated in order to determine their feasibility, parameter sensitivity and practical applicability. The salient feature of all schemes is that they do not require the rotor...... speed adaptation, that is, they are inherently sensorless observers. The most versatile is a dual-reference-frame observer. The other two schemes, implemented in stator frame and rotor frame, respectively, are simpler and are insensitive to detuning some of the motor parameters. Main theoretical aspects...

  20. Robust Control of Underactuated Systems: Higher Order Integral Sliding Mode Approach

    Directory of Open Access Journals (Sweden)

    Sami ud Din

    2016-01-01

    Full Text Available This paper presents a robust control design for the class of underactuated uncertain nonlinear systems. Either the nonlinear model of the underactuated systems is transformed into an input output form and then an integral manifold is devised for the control design purpose or an integral manifold is defined directly for the concerned class. Having defined the integral manifolds discontinuous control laws are designed which are capable of maintaining sliding mode from the very beginning. The closed loop stability of these systems is presented in an impressive way. The effectiveness and demand of the designed control laws are verified via the simulation and experimental results of ball and beam system.

  1. Fuzzy Sliding Mode Controller Design Using Takagi-Sugeno Modelled Nonlinear Systems

    Directory of Open Access Journals (Sweden)

    S. Bououden

    2013-01-01

    Full Text Available Adaptive fuzzy sliding mode controller for a class of uncertain nonlinear systems is proposed in this paper. The unknown system dynamics and upper bounds of the minimum approximation errors are adaptively updated with stabilizing adaptive laws. The closed-loop system driven by the proposed controllers is shown to be stable with all the adaptation parameters being bounded. The performance and stability of the proposed control system are achieved analytically using the Lyapunov stability theory. Simulations show that the proposed controller performs well and exhibits good performance.

  2. Designing Flexible Neuro-Fuzzy System Based on Sliding Mode Controller for Magnetic Levitation Systems

    OpenAIRE

    Zahra Mohammadi; Mohammad Teshnehlab; Mahdi Aliyari Shoorehdeli

    2011-01-01

    This study presents a novel controller of magnetic levitation system by using new neuro-fuzzy structures which called flexible neuro-fuzzy systems. In this type of controller we use sliding mode control with neuro-fuzzy to eliminate the Jacobian of plant. At first, we control magnetic levitation system with Mamdanitype neuro-fuzzy systems and logical-type neuro-fuzzy systems separately and then we use two types of flexible neuro-fuzzy systems as controllers. Basic flexible OR-type neuro-fuzzy...

  3. Super-twisting sliding mode direct torque contol of induction machine drives

    DEFF Research Database (Denmark)

    Lascu, Cristian; Blaabjerg, Frede

    2014-01-01

    This paper presents a new super-twisting sliding modes direct torque and flux controller (STSM-DTC) for induction motor (IM) drives. The STSM is a second-order (type two) variable-structure control which operates without high-frequency chattering. The proposed STSM scheme is a torque and stator...... flux magnitude controller implemented in the stator flux reference frame, and it does not employ current controllers as in conventional vector control. This controller contains a design parameter that allows the designer to balance its operation between a linear PI-like behavior and a constant...

  4. Terminal Sliding Mode Control with Adaptive Law for Uncertain Nonlinear System

    Directory of Open Access Journals (Sweden)

    Zhanshan Zhao

    2015-01-01

    Full Text Available A novel nonsingular terminal sliding mode controller is proposed for a second-order system with unmodeled dynamics uncertainties and external disturbances. We need not achieve the knowledge for boundaries of uncertainties and external disturbances in advance. The adaptive control gains are obtained to estimate the uncertain parameters and external disturbances which are unknown but bounded. The closed loop system stability is ensured with robustness and adaptation by the Lyapunov stability theorem in finite time. An illustrative example of second-order nonlinear system with unmodeled dynamics and external disturbances is given to demonstrate the effectiveness of the presented scheme.

  5. Sliding-Mode Based Idel Speed Control of an Automotive Engine

    Science.gov (United States)

    Sawut, Umerujan; Nakano, Kazushi

    This paper presents an application of model-based control techniques to automotive engine speed control systems. Althougt the modeling of nonlinear systems has been carried out for automotive engines including electronic-controlled throttle servo systems, there still remains the difficulty of the strong non-linearity due to the engine friction and manifold pressure functions. This paper proposes a design method of some engine speed control by analyzing the nonlinear systems using sliding-mode control paradigm. In comparison with the map-based control method, the effectiveness of the proposed control method is verified using simulation and experimental results on an experimental system.

  6. Sliding Mode Control Technique: Application to a Four Rotors Mini-Flying Robot

    Science.gov (United States)

    Zemalache, K. M.; Tahar, M.; Omari, A.; Maaref, H.

    2009-03-01

    This paper presents the study of stabilization with motion planning of the four rotors mini-flying robot (helicopter with four rotors). The dynamic model involves four control inputs which are computed to stabilize the engine with predefined trajectories path. The tracking feedback controller is based on receding horizon point to point steering. It is clear that our device belongs to families of under-actuated systems. Our aim is to obtain control algorithms using the cascade sliding mode approach in order to stabilize the engine and to generate its trajectory.

  7. Synchronization of a coupled Hodgkin-Huxley neurons via high order sliding-mode feedback

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Lopez, R. [Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana, Av. San Pablo No. 180, Reynosa-Tamaulipas, 02200 Azcapotzalco, Mexico, D.F. (Mexico)], E-mail: raguilar@correo.azc.uam.mx; Martinez-Guerra, R. [Departamento de Control Automatico, CINVESTAV-IPN, Apartado Postal 14-740, Mexico, D.F. C.P. 07360 (Mexico)], E-mail: rguerra@ctrl.cinvestav.mx

    2008-07-15

    This work deals with the synchronizations of two both coupled Hodgkin-Huxley (H-H) neurons, where the master neuron posses inner noise and the slave neuron is considered in a resting state, (without inner noise) and an exciting state (with inner noise). The synchronization procedure is done via a feedback control, considering a class of high order sliding-mode controller which provides chattering reduction and finite time synchronization convergence, with a satisfactory performance. Theoretical analysis is done in order to show the closed-loop stability of the proposed controller and the calculated finite time for convergence. The main results are illustrated via numerical experiments.

  8. Sliding Mode Control and Modified Generalized Projective Synchronization of a New Fractional-Order Chaotic System

    Directory of Open Access Journals (Sweden)

    Junbiao Guan

    2015-01-01

    Full Text Available A new fractional-order chaotic system is addressed in this paper. By applying the continuous frequency distribution theory, the indirect Lyapunov stability of this system is investigated based on sliding mode control technique. The adaptive laws are designed to guarantee the stability of the system with the uncertainty and external disturbance. Moreover, the modified generalized projection synchronization (MGPS of the fractional-order chaotic systems is discussed based on the stability theory of fractional-order system, which may provide potential applications in secure communication. Finally, some numerical simulations are presented to show the effectiveness of the theoretical results.

  9. Chattering-free sliding mode observer for speed sensorless control of PMSM

    Directory of Open Access Journals (Sweden)

    Mahmoud M. Gaballah

    2017-07-01

    Full Text Available This article presents a new speed observer based on fuzzy logic for speed sensorless control applications of permanent magnet synchronous motor “PMSM”. The switch function in traditional Sliding Mode Observer “SMO” is replaced by a rule based fuzzy logic system. The proposed observer not only improves the system dynamic performance during disturbances or parameter variations, but also has a high accuracy tracking performance with sufficient chattering reduction. The validity of the new observer corroborated through experimental results using TMS320F28069M Digital Signal Processor “DSP”.

  10. Sensorless sliding mode observer for a five-phase permanent magnet synchronous motor drive.

    Science.gov (United States)

    Hosseyni, Anissa; Trabelsi, Ramzi; Mimouni, Med Faouzi; Iqbal, Atif; Alammari, Rashid

    2015-09-01

    This paper deals with the sensorless vector controlled five-phase permanent magnet synchronous motor (PMSM) drive based on a sliding mode observer (SMO). The observer is designed considering the back electromotive force (EMF) of five-phase permanent magnet synchronous motor. The SMO structure and design are illustrated. Stability of the proposed observer is demonstrated using Lyapunov stability criteria. The proposed strategy is asymptotically stable in the context of Lyapunov theory. Simulated results on a five-phase PMSM drive are displayed to validate the feasibility and the effectiveness of the proposed control strategy. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  11. A novel fractional sliding mode control configuration for synchronizing disturbed fractional-order chaotic systems

    Science.gov (United States)

    Rabah, Karima; Ladaci, Samir; Lashab, Mohamed

    2017-09-01

    In this paper, a new design of fractional-order sliding mode control scheme is proposed for the synchronization of a class of nonlinear fractional-order systems with chaotic behaviour. The considered design approach provides a set of fractional-order laws that guarantee asymptotic stability of fractional-order chaotic systems in the sense of the Lyapunov stability theorem. Two illustrative simulation examples on the fractional-order Genesio-Tesi chaotic systems and the fractional-order modified Jerk systems are provided. These examples show the effectiveness and robustness of this control solution.

  12. Sliding mode control design of a ship steering autopilot with input saturation

    Directory of Open Access Journals (Sweden)

    Muhammad Ejaz

    2017-05-01

    Full Text Available In this article, a sliding mode control scheme for the autopilot system of a ship is presented, which also incorporates actuator saturation. Under the designed controller, the actuator doesn’t enter its saturation mode. Meanwhile, the stability of the closed-loop system can be guaranteed for the ship with input saturation. Fuzzy logic is used to handle gain to avoid the chattering effect, and it is compared with saturation function. The control system for the mathematical model of a scale replica of an “Esso Osaka” tanker is simulated in time domain for the effectiveness of the controller. The simulation results show that the proposed controller is more efficient as compared to the traditional and saturation function methods.

  13. A New Controller for PMSM Servo Drive Based on the Sliding Mode Approach with Parameter Adaptation

    Science.gov (United States)

    Gjini, Orges; Kaneko, Takayuki; Ohsawa, Hiroshi

    A novel controller based on the Sliding Mode (SM) approach is designed for controlling a permanent magnet synchronous motor (PMSM) in a servo drive. After analyzing the classical SM controller, changes are made in the controller design such that its performance is substantially improved. To improve the controller performance in steady state (zero error positioning) an integral block is added to the controller resulting in a new controller configuration, which we call Sliding Mode Integral (SMI) controller. The new controller is tuned based on the results from parameter identification of the motor and the working machine. To cope with model parameter variations, especially unpredictable friction changes, gain scheduling and fuzzy based adaptive techniques are used in the control algorithm. Experiments and simulations are carried out and their results show a high performance control. The new controller offers very good tracking; it is highly robust, reaches the final position very fast and has a large stall torque. Furthermore the application of the SM ensures reduction of the system order by one. For comparison, the new controller's performance is compared with that of a PI controller. From the experimental results it is obvious the superiority of the new proposed controller.

  14. Adaptive Integral Sliding Mode Stabilization of Nonholonomic Drift-Free Systems

    Directory of Open Access Journals (Sweden)

    Waseem Abbasi

    2016-01-01

    Full Text Available This article presents adaptive integral sliding mode control algorithm for the stabilization of nonholonomic drift-free systems. First the system is transformed, by using input transform, into a special structure containing a nominal part and some unknown terms which are computed adaptively. The transformed system is then stabilized using adaptive integral sliding mode control. The stabilizing controller for the transformed system is constructed that consists of the nominal control plus a compensator control. The compensator control and the adaptive laws are derived on the basis of Lyapunov stability theory. The proposed control algorithm is applied to three different nonholonomic drift-free systems: the unicycle model, the front wheel car model, and the mobile robot with trailer model. The controllability Lie algebra of the unicycle model contains Lie brackets of depth one, the model of a front wheel car contains Lie brackets of depths one and two, and the model of a mobile robot with trailer contains Lie brackets of depths one, two, and three. The effectiveness of the proposed control algorithm is verified through numerical simulations.

  15. Robust In-Flight Sensor Fault Diagnostics for Aircraft Engine Based on Sliding Mode Observers.

    Science.gov (United States)

    Chang, Xiaodong; Huang, Jinquan; Lu, Feng

    2017-04-11

    For a sensor fault diagnostic system of aircraft engines, the health performance degradation is an inevitable interference that cannot be neglected. To address this issue, this paper investigates an integrated on-line sensor fault diagnostic scheme for a commercial aircraft engine based on a sliding mode observer (SMO). In this approach, one sliding mode observer is designed for engine health performance tracking, and another for sensor fault reconstruction. Both observers are employed in in-flight applications. The results of the former SMO are analyzed for post-flight updating the baseline model of the latter. This idea is practical and feasible since the updating process does not require the algorithm to be regulated or redesigned, so that ground-based intervention is avoided, and the update process is implemented in an economical and efficient way. With this setup, the robustness of the proposed scheme to the health degradation is much enhanced and the latter SMO is able to fulfill sensor fault reconstruction over the course of the engine life. The proposed sensor fault diagnostic system is applied to a nonlinear simulation of a commercial aircraft engine, and its effectiveness is evaluated in several fault scenarios.

  16. Decentralized adaptive sliding mode control of a space robot actuated by control moment gyroscopes

    Directory of Open Access Journals (Sweden)

    Jia Yinghong

    2016-06-01

    Full Text Available An adaptive sliding mode control (ASMC law is proposed in decentralized scheme for trajectory tracking control of a new concept space robot. Each joint of the system is a free ball joint capable of rotating with three degrees of freedom (DOF. A cluster of control moment gyroscopes (CMGs is mounted on each link and the base to actuate the system. The modified Rodrigues parameters (MRPs are employed to describe the angular displacements, and the equations of motion are derived using Kane’s equations. The controller for each link or the base is designed separately in decentralized scheme. The unknown disturbances, inertia parameter uncertainties and nonlinear uncertainties are classified as a “lumped” matched uncertainty with unknown upper bound, and a continuous sliding mode control (SMC law is proposed, in which the control gain is tuned by the improved adaptation laws for the upper bound on norm of the uncertainty. A general amplification function is designed and incorporated in the adaptation laws to reduce the control error without conspicuously increasing the magnitude of the control input. Uniformly ultimate boundedness of the closed loop system is proved by Lyapunov’s method. Simulation results based on a three-link system verify the effectiveness of the proposed controller.

  17. A new fuzzy sliding mode controller for vibration control systems using integrated-structure smart dampers

    Science.gov (United States)

    Dzung Nguyen, Sy; Kim, Wanho; Park, Jhinha; Choi, Seung-Bok

    2017-04-01

    Vibration control systems using smart dampers (SmDs) such as magnetorheological and electrorheological dampers (MRD and ERD), which are classified as the integrated structure-SmD control systems (ISSmDCSs), have been actively researched and widely used. This work proposes a new controller for a class of ISSmDCSs in which high accuracy of SmD models as well as increment of control ability to deal with uncertainty and time delay are to be expected. In order to achieve this goal, two formualtion steps are required; a non-parametric SmD model based on an adaptive neuro-fuzzy inference system (ANFIS) and a novel fuzzy sliding mode controller (FSMC) which can weaken the model error of the ISSmDCSs and hence provide enhanced vibration control performances. As for the formulation of the proposed controller, first, an ANFIS controller is desgned to identify SmDs using the improved control algorithm named improved establishing neuro-fuzzy system (establishing neuro-fuzzy system). Second, a new control law for the FSMC is designed via Lyapunov stability analysis. An application to a semi-active MRD vehicle suspension system is then undertaken to illustrate and evaluate the effectiveness of the proposed control method. It is demonstrated through an experimental realization that the FSMC proposed in this work shows superior vibration control performance of the vehicle suspension compared to other surveyed controller which have similar structures to the FSMC, such as fuzzy logic and sliding mode control.

  18. Output Feedback Fractional-Order Nonsingular Terminal Sliding Mode Control of Underwater Remotely Operated Vehicles

    Science.gov (United States)

    Chen, Jiawang; Gu, Linyi

    2014-01-01

    For the 4-DOF (degrees of freedom) trajectory tracking control problem of underwater remotely operated vehicles (ROVs) in the presence of model uncertainties and external disturbances, a novel output feedback fractional-order nonsingular terminal sliding mode control (FO-NTSMC) technique is introduced in light of the equivalent output injection sliding mode observer (SMO) and TSMC principle and fractional calculus technology. The equivalent output injection SMO is applied to reconstruct the full states in finite time. Meanwhile, the FO-NTSMC algorithm, based on a new proposed fractional-order switching manifold, is designed to stabilize the tracking error to equilibrium points in finite time. The corresponding stability analysis of the closed-loop system is presented using the fractional-order version of the Lyapunov stability theory. Comparative numerical simulation results are presented and analyzed to demonstrate the effectiveness of the proposed method. Finally, it is noteworthy that the proposed output feedback FO-NTSMC technique can be used to control a broad range of nonlinear second-order dynamical systems in finite time. PMID:24983004

  19. Control of input delayed pneumatic vibration isolation table using adaptive fuzzy sliding mode

    Directory of Open Access Journals (Sweden)

    Mostafa Khazaee

    Full Text Available AbstractPneumatic isolators are promising candidates for increasing the quality of accurate instruments. For this purpose, higher performance of such isolators is a prerequisite. In particular, the time-delay due to the air transmission is an inherent issue with pneumatic systems, which needs to be overcome using modern control methods. In this paper an adaptive fuzzy sliding mode controller is proposed to improve the performance of a pneumatic isolator in the low frequency range, i.e., where the passive techniques have obvious shortcomings. The main idea is to combine the adaptive fuzzy controller with adaptive predictor as a new time delay control technique. The adaptive fuzzy sliding mode control and the adaptive fuzzy predictor help to circumvent the input delay and nonlinearities in such isolators. The main advantage of the proposed method is that the closed-loop system stability is guaranteed under certain conditions. Simulation results reveal the effectiveness of the proposed method, compared with other existing time -delay control methods.

  20. Direct Torque Control of a Small Wind Turbine with a Sliding-Mode Speed Controller

    Science.gov (United States)

    Sri Lal Senanayaka, Jagath; Karimi, Hamid Reza; Robbersmyr, Kjell G.

    2016-09-01

    In this paper. the method of direct torque control in the presence of a sliding-mode speed controller is proposed for a small wind turbine being used in water heating applications. This concept and control system design can be expanded to grid connected or off-grid applications. Direct torque control of electrical machines has shown several advantages including very fast dynamics torque control over field-oriented control. Moreover. the torque and flux controllers in the direct torque control algorithms are based on hvsteretic controllers which are nonlinear. In the presence of a sliding-mode speed control. a nonlinear control system can be constructed which is matched for AC/DC conversion of the converter that gives fast responses with low overshoots. The main control objectives of the proposed small wind turbine can be maximum power point tracking and soft-stall power control. This small wind turbine consists of permanent magnet synchronous generator and external wind speed. and rotor speed measurements are not required for the system. However. a sensor is needed to detect the rated wind speed overpass events to activate proper speed references for the wind turbine. Based on the low-cost design requirement of small wind turbines. an available wind speed sensor can be modified. or a new sensor can be designed to get the required measurement. The simulation results will be provided to illustrate the excellent performance of the closed-loop control system in entire wind speed range (4-25 m/s).

  1. Energy optimized sliding-mode control of sensorless induction motor drives

    Energy Technology Data Exchange (ETDEWEB)

    Hajian, M.; Soltani, J.; Hoseinnia, S. [Faculty of Electrical and Computer Engineering, Isfahan Univ. of Technology, Isfahan (Iran); Arab Markadeh, G.R. [Faculty of Engineering, Univ. of Shahrekord, Shahrekord (Iran)

    2009-09-15

    In this paper a sensorless sliding-mode (SM) direct torque and flux control is described for three-phase induction motor (IM) drive. The IM drive is supplied with a two level space vector modulation (SVM) voltage source inverter. A conventional PI speed controller is employed to generate the desired torque command in the case of speed control. Stator and rotor flux vectors are estimated using a sliding-mode observer and are employed in rotor speed estimation. Moreover, the IM model includes the iron losses through a speed dependent shunt resistance in the motor two axis equivalent circuits. Motor efficiency is also optimized by adjusting the magnitude of the stator flux reference for each value of motor load and speed. For this purpose, an on-line search method (OSM) is adopted. According to this method, for each given value of load torque and rotor speed, the stator flux reference is adjusted so that the average of real input power becomes minimized. Simulation and experimental results are presented to show the capability and validity of the proposed control scheme. (author)

  2. Adaptive Backstepping Sliding-Mode Control of the Electronic Throttle System in Modern Automobiles

    Directory of Open Access Journals (Sweden)

    Rui Bai

    2014-01-01

    Full Text Available In modern automobiles, electronic throttle is a DC-motor-driven valve that regulates air inflow into the vehicle’s combustion system. The electronic throttle is increasingly being used in order to improve the vehicle drivability, fuel economy, and emissions. Electronic throttle system has the nonlinear dynamical characteristics with the unknown disturbance and parameters. At first, the dynamical nonlinear model of the electronic throttle is built in this paper. Based on the model and using the backstepping design technique, a new adaptive backstepping sliding-mode controller of the electronic throttle is developed. During the backstepping design process, parameter adaptive law is designed to estimate the unknown parameter, and sliding-mode control term is applied to compensate the unknown disturbance. The proposed controller can make the actual angle of the electronic throttle track its set point with the satisfactory performance. Finally, a computer simulation is performed, and simulation results verify that the proposed control method can achieve favorable tracking performance.

  3. Design of LPV-Based Sliding Mode Controller with Finite Time Convergence for a Morphing Aircraft

    Directory of Open Access Journals (Sweden)

    Nuan Wen

    2017-01-01

    Full Text Available This paper proposes a finite time convergence sliding mode control (FSMC strategy based on linear parameter-varying (LPV methodology for the stability control of a morphing aircraft subject to parameter uncertainties and external disturbances. Based on the Kane method, a longitudinal dynamic model of the morphing aircraft is built. Furthermore, the linearized LPV model of the aircraft in the wing transition process is obtained, whose scheduling parameters are wing sweep angle and wingspan. The FSMC scheme is developed into LPV systems by applying the previous results for linear time-invariant (LTI systems. The sufficient condition in form of linear matrix inequality (LMI constraints is derived for the existence of a reduced-order sliding mode, in which the dynamics can be ensured to keep robust stability and L2 gain performance. The tensor-product (TP model transformation approach can be directly applied to solve infinite LMIs belonging to the polynomial parameter-dependent LPV system. Then, by the parameter-dependent Lyapunov function stability analysis, the synthesized FSMC is proved to drive the LPV system trajectories toward the predefined switching surface with a finite time arrival. Comparative simulation results in the nonlinear model demonstrate the robustness and effectiveness of this approach.

  4. Second Order Sliding Mode Control Scheme for an Autonomous Underwater Vehicle with Dynamic Region Concept

    Directory of Open Access Journals (Sweden)

    Zool H. Ismail

    2015-01-01

    Full Text Available The main goal in developing closed loop control system for an Autonomous Underwater Vehicle (AUV is to make a robust vehicle from natural and exogenous perturbations such as wind, wave, and ocean currents. However a well-known robust control, for instance, Sliding Mode Controller (SMC, gives a chattering effect and it influences the stability of an AUV. Furthermore, some researchers combined other controls to get better result but it tends to present long computational time and causes large energy consumption. Thus, this paper proposed a Super Twisting Sliding Mode Controller (STSMC with dynamic region concept for an AUV. STSMC or a second order SMC is adopted as a robust controller which is free from chattering effect. Meanwhile, the implementation of dynamic region is useful to reduce the energy usage. As a result, the proposed controller obtains global asymptotic stability which is validated by using Lyapunov-like function. Moreover, some simulations present the efficiency of proposed controller. In conclusion, STSMC with region based control is effective to be applied for the robust tracking of an AUV. It contributes to give a fast response when handling the perturbations, short computational time, and low energy demand.

  5. On Position Sensorless Control for Permanent Magnet Synchronous Motor Based on a New Sliding Mode Observer

    Directory of Open Access Journals (Sweden)

    Qixin Zhu

    2014-10-01

    Full Text Available For the problems of buffeting and phase delay in traditional rotor detection in sensorless vector control of permanent magnet synchronous motor (PMSM, the Sigmoid function is proposed to replace sign function and the approach of piecewise linearization is proposed to compensate phase delay. To the problem that the output of traditional low pass filter contains high- order harmonic, two-stage filter including traditional low-pass filter and Kalman filter is proposed in this paper. Based on the output of traditional first-order low-pass filter, the Kalman filter is used to get modified back-EMF. The phase-locked loop control of rotor position is adopted to estimate motor position and speed. A Matlab/Simulink simulation model of PMSM position servo control system is established. The simulation analysis of the new sliding mode observer’s back-EMF detection, position and speed estimation, load disturbance and dynamic process are carried out respectively. Simulation results verify feasibility of the new sliding mode observer algorithm.

  6. Sliding mode direct power control of RSC for DFIGs driven by variable speed wind turbines

    Directory of Open Access Journals (Sweden)

    E.G. Shehata

    2015-12-01

    Full Text Available In spite of its several advantages, a classic direct power control (DPC of doubly fed induction generators (DFIGs driven by variable speed wind turbines has some drawbacks. In this paper, a simple and robust total sliding mode controller (TSMC is designed to improve the classical DPC performance without complicating the overall scheme. The TSMC is designed to regulate the DFIG stator active and reactive powers. Two integral switching functions are selected for describing the switching surfaces of the active and reactive powers. Reaching phase stability problem of the classical sliding mode controller is avoided in the proposed TSMC. Neither current control loops nor accurate values of machine parameters are required in the proposed scheme. In addition, axes transformation of the stator voltage and current are eliminated. The grid side converter is controlled based on DPC principle to regulate both DC-link voltage and total reactive power. The feasibility of the proposed DPC scheme is validated through simulation studies on a 1.5 MW wind power generation system. The performance of the proposed and conventional DPC schemes is compared under different operating conditions.

  7. A multi-mode operation control strategy for flexible microgrid based on sliding-mode direct voltage and hierarchical controls.

    Science.gov (United States)

    Zhang, Qinjin; Liu, Yancheng; Zhao, Youtao; Wang, Ning

    2016-03-01

    Multi-mode operation and transient stability are two problems that significantly affect flexible microgrid (MG). This paper proposes a multi-mode operation control strategy for flexible MG based on a three-layer hierarchical structure. The proposed structure is composed of autonomous, cooperative, and scheduling controllers. Autonomous controller is utilized to control the performance of the single micro-source inverter. An adaptive sliding-mode direct voltage loop and an improved droop power loop based on virtual negative impedance are presented respectively to enhance the system disturbance-rejection performance and the power sharing accuracy. Cooperative controller, which is composed of secondary voltage/frequency control and phase synchronization control, is designed to eliminate the voltage/frequency deviations produced by the autonomous controller and prepare for grid connection. Scheduling controller manages the power flow between the MG and the grid. The MG with the improved hierarchical control scheme can achieve seamless transitions from islanded to grid-connected mode and have a good transient performance. In addition the presented work can also optimize the power quality issues and improve the load power sharing accuracy between parallel VSIs. Finally, the transient performance and effectiveness of the proposed control scheme are evaluated by theoretical analysis and simulation results. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  8. On the synthesis of sliding mode controller for the autopilot design of free flight system

    Science.gov (United States)

    Devika K., B.; Thomas, Susy

    2017-01-01

    Today's rapid growth in air transportation demand leads to the problem of congestion in air traffic routes. In recent years, free flight concept is widely discussed as the solution to this problem. Free flight is a decentralized method of air traffic management, in which each aircraft has the freedom to self optimize its own route. Conflict detection and its subsequent resolution are the major challenges in the realization of this concept. Today's modern navigation and surveillance equipment can ensure accurate conflict predictions. Once a conflict is detected, it should be avoided through suitable conflict avoidance maneuvers. An autopilot capable of initiating these conflict free maneuvers should be a necessary part of any aircraft in free flight to ensure conflict avoided flight. Controller design based on Sliding Mode Control (SMC) strategy is presented in this paper for the purpose of free flight autopilot implementation. Since SMC has the inherent property of robustness in sliding mode, it can ensure a highly efficient autopilot design. Conventional and reaching law approaches of SMC design are considered here for controller design. Conventional SMC technique usually exhibits an unacceptable phenomenon, viz., chattering. Reaching law approaches for SMC design are being investigated here so as to identify an appropriate strategy that can ensure near chattering free operation. Considering typical free flight conflict avoidance modes of operation, the performance of all the considered SMC strategies are compared through simulation studies. The comparison is based on their ability to reduce chattering and the effectiveness in ensuring quick conflict resolution maneuvers, so that an efficient controller for free flight autopilot system can be recommended.

  9. Optimal Design of Fractional Sliding Mode Control Based on Multi-Objective Genetic Algorithm for a Two-Link Flexible Manipulator

    Directory of Open Access Journals (Sweden)

    Milad Pouya

    2017-09-01

    Full Text Available In this paper a novel optimal approach of control strategy is introduced by applying fractional calculus in structure of sliding mode control for a range of dynamics system liable to uncertainties. So, a fractional sliding mode control was designed for dynamics of the two-link rigid-flexible manipulator. Furthermore a multi-objective genetic algorithm was proposed in order to find the ideal variable structure of the sliding mode control. Optimal variables achieved by optimization of the conventional sliding mode control. Then the performance of the both conventional and the fractional sliding mode control were compared with respect to optimal variables. Results indicated that by applying the optimized fractional sliding mode control, system’s error was significantly reduced and, so as tracking the desired value was done with a high accuracy and also a smooth control action was achieved.

  10. Tracking Control of an Ultrasonic Linear Motor Actuated Stage Using a Sliding-mode Controller with Friction Compensation

    Directory of Open Access Journals (Sweden)

    Chih-Jer Lin

    2015-02-01

    Full Text Available The purpose of this paper is to investigate the nonlinear friction and compensation for a piezoelectric ceramic ultrasonic motor (USM. Although the architecture of the USM is different from the general electric-mechanical motor, the mathematic model for the USM motor can use the same friction model to formulate the friction phenomenon. To establish the feed-forward controller, the system identification for the USM is needed to study to design the model-based controller. To obtain the optimal system parameters of the USM, PSO and CSS algorithms are studied to identify the system parameters for the nonlinear friction model. For the controller design, a non-model based controller, using back-propagation neural network controller to perform tracking tasks, and the model-based controller, which consists of the feed-forward controller based on the system identification and the sliding-mode control, are discussed in this paper. Finally, the two real-time tracking tasks are used to validate the proposed method.

  11. a New Approach to the Sliding Mode Control Design: Anti-Lock Braking System as a Case Study

    Science.gov (United States)

    Perie, Staniša Lj.; Antic, Dragan S.; Nikolic, Vlastimir D.; Mitic, Darko B.; Milojkovic, Marko T.; Nikolic, Šaša S.

    2014-01-01

    In this paper we introduce a new approach to the sliding mode control design based on orthogonal models. First, we discuss the sliding mode control based on a model given in controllable canonical form. Then, we design almost orthogonal filters based on almost orthogonal polynomials of M¨untz-Legendre type. The advantage of the almost orthogonal filters is that they can be used for the modelling and analysis of systems with nonlinearities and imperfections. Herein, we use a designed filter to obtain several linearized models of an unknown system in different working areas. For each of these linearized models, corresponding sliding mode controller is designed and the switching between controls laws depends only on input signal. The experimental results and comparative analysis with relay control, already installed in laboratory equipment, verify the efficiency and excellent performance of such a control in the case of anti-lock braking system.

  12. Pareto Design of Decoupled Sliding-Mode Controllers for Nonlinear Systems Based on a Multiobjective Genetic Algorithm

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    M. J. Mahmoodabadi

    2012-01-01

    Full Text Available This paper presents Pareto design of decoupled sliding-mode controllers based on a multiobjective genetic algorithm for several fourth-order coupled nonlinear systems. In order to achieve an optimum controller, at first, the decoupled sliding mode controller is applied to stablize the fourth-order coupled nonlinear systems at the equilibrium point. Then, the multiobjective genetic algorithm is applied to search the optimal coefficients of the decoupled sliding-mode control to improve the performance of the control system. Considered objective functions are the angle and distance errors. Finally, the simulation results implemented in the MATLAB software environment are presented for the inverted pendulum, ball and beam, and seesaw systems to assure the effectiveness of this technique.

  13. Fractional order sliding-mode control based on parameters auto-tuning for velocity control of permanent magnet synchronous motor.

    Science.gov (United States)

    Zhang, BiTao; Pi, YouGuo; Luo, Ying

    2012-09-01

    A fractional order sliding mode control (FROSMC) scheme based on parameters auto-tuning for the velocity control of permanent magnet synchronous motor (PMSM) is proposed in this paper. The control law of the proposed F(R)OSMC scheme is designed according to Lyapunov stability theorem. Based on the property of transferring energy with adjustable type in F(R)OSMC, this paper analyzes the chattering phenomenon in classic sliding mode control (SMC) is attenuated with F(R)OSMC system. A fuzzy logic inference scheme (FLIS) is utilized to obtain the gain of switching control. Simulations and experiments demonstrate that the proposed FROSMC not only achieve better control performance with smaller chatting than that with integer order sliding mode control, but also is robust to external load disturbance and parameter variations. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

  14. Adaptive Sliding Mode Control Design of a SCARA Robot Manipulator System Under Parametric Variations

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    F. Adelhed

    2015-12-01

    Full Text Available – The sliding mode control (SMC has yet proven its efficiency through several theoretical researches. Indeed, the robotic field is recognized as one of the main SMC portals on practical implementations. The interest of this work consists in testing the SMC robustness and its reliability versus the parameters variation and model uncertainties. In this paper, an algorithm for trajectory tracking task of robot manipulators based on a SMC has been proposed. Then, aiming to deal with the presence of disturbances and parametric modeling uncertainties, the adopted control law has been extended to an adaptive SMC version based integral sliding surface, where the selection of the parameters adaptation law has been detailed. It has been proven that the adaptive control design can stabilize both position and velocity of the system, where the explicit use of the system dynamic model becomes no longer required. Simulation results performed on a SCARA robot manipulator reveal improving control acting clearly denoted by the introduction of the adaptive control design

  15. Design and implementation of a novel sliding mode sensing architecture for capacitive MEMS accelerometers

    Science.gov (United States)

    Sarraf, E. H.; Cousins, B.; Cretu, E.; Mirabbasi, S.

    2011-11-01

    We propose novel feedback control and sensing schemes based on sliding mode control (SMC) for closed-loop micro-accelerometers as alternative digital control architectures to sigma-delta (ΣΔ) approaches. The under-damped micro-device has been designed in Coventorware, fabricated in SOIMUMPs (25 µm thick structural layer) technology and experimentally characterized using a Polytec MSA-500 (micro-system analyzer) equipment. To verify the system architecture robustness, the application of SMC is extended to an over-damped accelerometer model. In either case, the SMC demonstrates the repositioning of the proof mass to null position; however, the over-damped model exhibits shorter transition time (15 ms for 1g acceleration) due to the increased damping. In addition to that, we extend the usage of SMC beyond the classical actuation problem to a novel sensing problem where we demonstrate the extraction of the external acceleration measurement from the switching behavior along the sliding surface. An optimized fixed-point implementation is targeted on a field-programmable gate array (FPGA) using rapid prototyping methodology, where the new proposed method has been compared for reference with a control scheme that employs a ΣΔ modulator. The SMC-based architecture is advantageous in terms of hardware complexity, and the control of the number of degrees of freedom required by an inertial measurement unit can be accommodated on a low-cost FPGA device. SMC offers a sound theoretical framework for the nonlinear control of inertial sensors.

  16. Fractional fuzzy adaptive sliding-mode control of a 2-DOF direct-drive robot arm.

    Science.gov (United States)

    Efe, Mehmet Onder

    2008-12-01

    This paper presents a novel parameter adjustment scheme to improve the robustness of fuzzy sliding-mode control achieved by the use of an adaptive neuro-fuzzy inference system (ANFIS) architecture. The proposed scheme utilizes fractional-order integration in the parameter tuning stage. The controller parameters are tuned such that the system under control is driven toward the sliding regime in the traditional sense. After a comparison with the classical integer-order counterpart, it is seen that the control system with the proposed adaptation scheme displays better tracking performance, and a very high degree of robustness and insensitivity to disturbances are observed. The claims are justified through some simulations utilizing the dynamic model of a 2-DOF direct-drive robot arm. Overall, the contribution of this paper is to demonstrate that the response of the system under control is significantly better for the fractional-order integration exploited in the parameter adaptation stage than that for the classical integer-order integration.

  17. IPMSM velocity and current control using MTPA based adaptive fractional order sliding mode controller

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    Sayed Hamed Hosseini

    2017-06-01

    Full Text Available This paper presents a two-loop approach for velocity and stator currents control of an Interior-type Permanent Magnet Synchronous Motor (IPMSM. In the outer loop, the reference torque obtained from a conventional PI controller gives two-axis stator reference currents based on Maximum-Torque per Ampere (MTPA strategy. In the inner loop, an adaptive fractional order sliding mode controller is designed to reach the two-axis stator currents to their reference values obtained from the MTPA method. To achieve this idea, fractional order sliding surfaces and an adaptive controller with adjustable parameters are employed. The adaptive controller is designed to increase the robustness of the proposed method against the uncertainties in stator resistance and inductances. A Lyapunov based adaptation mechanism is proposed for adjustment of the controller parameters. The optimal value of the fractional orders are obtained by optimization of an integral time absolute error performance index. The simulation results show the robustness of the proposed method against the uncertainties in stator resistance and stator inductances.

  18. Least square based sliding mode control for a quad-rotor helicopter and energy saving by chattering reduction

    Science.gov (United States)

    Sumantri, Bambang; Uchiyama, Naoki; Sano, Shigenori

    2016-01-01

    In this paper, a new control structure for a quad-rotor helicopter that employs the least squares method is introduced. This proposed algorithm solves the overdetermined problem of the control input for the translational motion of a quad-rotor helicopter. The algorithm allows all six degrees of freedom to be considered to calculate the control input. The sliding mode controller is applied to achieve robust tracking and stabilization. A saturation function is designed around a boundary layer to reduce the chattering phenomenon that is a common problem in sliding mode control. In order to improve the tracking performance, an integral sliding surface is designed. An energy saving effect because of chattering reduction is also evaluated. First, the dynamics of the quad-rotor helicopter is derived by the Newton-Euler formulation for a rigid body. Second, a constant plus proportional reaching law is introduced to increase the reaching rate of the sliding mode controller. Global stability of the proposed control strategy is guaranteed based on the Lyapunov's stability theory. Finally, the robustness and effectiveness of the proposed control system are demonstrated experimentally under wind gusts, and are compared with a regular sliding mode controller, a proportional-differential controller, and a proportional-integral-differential controller.

  19. Experimental Study of Flexible Plate Vibration Control by Using Two-Loop Sliding Mode Control Strategy

    Science.gov (United States)

    Yang, Jingyu; Lin, Jiahui; Liu, Yuejun; Yang, Kang; Zhou, Lanwei; Chen, Guoping

    2017-08-01

    It is well known that intelligent control theory has been used in many research fields, novel modeling method (DROMM) is used for flexible rectangular active vibration control, and then the validity of new model is confirmed by comparing finite element model with new model. In this paper, taking advantage of the dynamics of flexible rectangular plate, a two-loop sliding mode (TSM) MIMO approach is introduced for designing multiple-input multiple-output continuous vibration control system, which can overcome uncertainties, disturbances or unstable dynamics. An illustrative example is given in order to show the feasibility of the method. Numerical simulations and experiment confirm the effectiveness of the proposed TSM MIMO controller.

  20. Development of Sliding Mode Controller for a Modified Boost Ćuk Converter Configuration

    Directory of Open Access Journals (Sweden)

    Sanjeevikumar Padmanaban

    2017-09-01

    Full Text Available This paper introduces a sliding mode control (SMC-based equivalent control method to a novel high output gain Ćuk converter. An additional inductor and capacitor improves the efficiency and output gain of the classical Ćuk converter. Classical proportional integral (PI controllers are widely used in direct current to direct current (DC-DC converters. However, it is a very challenging task to design a single PI controller operating in different loads and disturbances. An SMC-based equivalent control method which achieves a robust operation in a wide operation range is also proposed. Switching frequency is kept constant in appropriate intervals at different loading and disturbance conditions by implementing a dynamic hysteresis control method. Numerical simulations conducted in MATLAB/Simulink confirm the accuracy of analysis of high output gain modified Ćuk converter. In addition, the proposed equivalent control method is validated in different perturbations to demonstrate robust operation in wide operation range.

  1. Sliding mode coordination control for multiagent systems with underactuated agent dynamics

    Science.gov (United States)

    Ghasemi, Masood; Nersesov, Sergey G.; Clayton, Garrett; Ashrafiuon, Hashem

    2014-12-01

    In this paper, we develop a new integrated coordinated control and obstacle avoidance approach for a general class of underactuated agents. We use graph-theoretic notions to characterise communication topology in the network of underactuated agents as determined by the information flow directions and captured by the graph Laplacian matrix. Obstacle avoidance is achieved by surrounding the stationary as well as moving obstacles by elliptical or other convex shapes that serve as stable periodic solutions to planar systems of ordinary differential equations and using transient trajectories of those systems to navigate the agents around the obstacles. Decentralised controllers for individual agents are designed using sliding mode control approach and are only based on data communicated from the neighbouring agents. We demonstrate the efficacy of our theoretical approach using an example of a system of wheeled mobile robots that reach and maintain a desired formation. Finally, we validate our results experimentally.

  2. Integral Sliding Mode Control Strategy of D-STATCOM for Unbalanced Load Compensation under Various Disturbances

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    Mingchao Xia

    2013-01-01

    Full Text Available Control strategies of D-STATCOM for unbalanced load compensation under internal and external disturbances were discussed. Linear control strategies do not have a satisfactory dynamic performance and become invalid under internal or external disturbances. To guarantee a good precision and robustness, a control strategy combining input-output feedback linearization technique with integral sliding mode control (ISMC method was applied to D-STATCOM for unbalanced load compensation. The strategy has features of simple structure and is easy to implement. A 10 MVar/10 kV D-STATCOM simulation system was built in PSCAD/EMTDC to verify the effectiveness and robustness of the control strategy proposed. Simulation results show that the control strategy can compensate reactive power and eliminate unbalance simultaneously under various disturbances.

  3. Discrete Second-Order Sliding Mode Adaptive Controller Based on Characteristic Model for Servo Systems

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    Zhihong Wang

    2015-01-01

    Full Text Available Considering the varying inertia and load torque in high speed and high accuracy servo systems, a novel discrete second-order sliding mode adaptive controller (DSSMAC based on characteristic model is proposed, and a command observer is also designed. Firstly, the discrete characteristic model of servo systems is established. Secondly, the recursive least square algorithm is adopted to identify time-varying parameters in characteristic model, and the observer is applied to predict the command value of next sample time. Furthermore, the stability of the closed-loop system and the convergence of the observer are analyzed. The experimental results show that the proposed method not only can adapt to varying inertia and load torque, but also has good disturbance rejection ability and robustness to uncertainties.

  4. Continuous high order sliding mode controller design for a flexible air-breathing hypersonic vehicle.

    Science.gov (United States)

    Wang, Jie; Zong, Qun; Su, Rui; Tian, Bailing

    2014-05-01

    This paper investigates the problem of tracking control with uncertainties for a flexible air-breathing hypersonic vehicle (FAHV). In order to overcome the analytical intractability of this model, an Input-Output linearization model is constructed for the purpose of feedback control design. Then, the continuous finite time convergence high order sliding mode controller is designed for the Input-Output linearization model without uncertainties. In addition, a nonlinear disturbance observer is applied to estimate the uncertainties in order to compensate the controller and disturbance suppression, where disturbance observer and controller synthesis design is obtained. Finally, the synthesis of controller and disturbance observer is used to achieve the tracking for the velocity and altitude of the FAHV and simulations are presented to illustrate the effectiveness of the control strategies. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Sliding Mode Based Self-Tuning PID Controller for Second Order Systems

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    Alper BAYRAK

    2017-11-01

    Full Text Available In this paper, a sliding mode based self-tuning PID controller is proposed for uncertain second order systems. While developing the controller, it is assumed that the system model has a part which contains nonlinear terms similar to PID structure which is a new approach in the literature. The controller and update rules for controller parameters are obtained from Lyapunov stability analysis. The proposed controller with update rule is experienced on an experimental 2-DOF helicopter which is also known as Twin-Rotor Multi-Input Multi-Output System (TRMS. From experiments, it was seen that the PID parameter update rules run satisfactorily and, in parallel with this, the controller achieved the control objective by providing the system track the desired trajectory.

  6. Fault tolerant control based on interval type-2 fuzzy sliding mode controller for coaxial trirotor aircraft.

    Science.gov (United States)

    Zeghlache, Samir; Kara, Kamel; Saigaa, Djamel

    2015-11-01

    In this paper, a robust controller for a Six Degrees of Freedom (6 DOF) coaxial trirotor helicopter control is proposed in presence of defects in the system. A control strategy based on the coupling of the interval type-2 fuzzy logic control and sliding mode control technique are used to design a controller. The main purpose of this work is to eliminate the chattering phenomenon and guaranteeing the stability and the robustness of the system. In order to achieve this goal, interval type-2 fuzzy logic control has been used to generate the discontinuous control signal. The simulation results have shown that the proposed control strategy can greatly alleviate the chattering effect, and perform good reference tracking in presence of defects in the system. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Impedance Control of the Rehabilitation Robot Based on Sliding Mode Control

    Science.gov (United States)

    Zhou, Jiawang; Zhou, Zude; Ai, Qingsong

    As an auxiliary treatment, the 6-DOF parallel robot plays an important role in lower limb rehabilitation. In order to improve the efficiency and flexibility of the lower limb rehabilitation training, this paper studies the impedance controller based on the position control. A nonsingular terminal sliding mode control is developed to ensure the trajectory tracking precision and in contrast to traditional PID control strategy in the inner position loop, the system will be more stable. The stability of the system is proved by Lyapunov function to guarantee the convergence of the control errors. Simulation results validate the effectiveness of the target impedance model and show that the parallel robot can adjust gait trajectory online according to the human-machine interaction force to meet the gait request of patients, and changing the impedance parameters can meet the demands of different stages of rehabilitation training.

  8. The study of antilock braking system based on sliding mode variable structure control

    Science.gov (United States)

    Liu, GuoFu; Zhang, Qi; Wang, Yueke; Liu, Bo

    2006-11-01

    The friction characteristic between road surface and tire makes the anti-lock braking system (ABS) take on the properties of nonlinearity, time variation and uncertainties. The sliding mode variable structure controller (SMVSC) has strong robust ability in dealing with uncertainties including the model error and unknown interference, so SMVSC is used in ABS extensively. In order to achieve expected performance, SMVSC has to identify the road characteristics in real time. The mathematical model of ABS is established, and the application of SMVSC in ABS is realized. One kind of estimation algorithm of optimal slip ratio based on the shape of μ-λ curve is proposed. By computer simulation, the feasibility and validity of SMVSC based on optimal slip ratio is verified.

  9. Simulation of a Matrix Converter Fed Drive With Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Jan Bauer

    2012-01-01

    Full Text Available Induction machines are among the most widely used electrical-to-mechanical converters in electric drives. Their advantageous robustness and simplicity goes hand-in-hand with complicated control. A converter with a suitable control algorithm is needed in order to withdraw maximum power and dynamics from the drive. In recent times, control methods such as those based on DTC and sliding mode methods have come to the forefront, due to their robustness and relative simplicity.In the field of power converters, new converter topologies are emerging with improved efficiency that pushes the operation limits of the drive. This paper focuses on the development of a control of this kind of strategy for an induction machine fed from a matrix converter.

  10. LMI approach for sliding mode control and analysis of DC-DC converters

    Directory of Open Access Journals (Sweden)

    Lekić Aleksandra D.

    2016-01-01

    Full Text Available Circuits' and in particular DC/DC converters' switching behavior is analyzed in this paper using the equivalent control modeling of the dynamic systems' sliding mode regime. As a representative example and also being one of the0 most complex circuits among DC/DC converters, the Ćuk converter is chosen. It is shown how the converter's behavior in the steady state regime can be studied and analyzed by the linear matrix inequalities based stability conditions for linear dynamic systems with nonlinear sector bounded perturbations. The maximization of the nonlinear sector bound provides a limit for applying the linear ripple approximation in the converter operation analysis. Furthermore, our approach is validated by providing simulation results for two different switching surfaces of practical interest.

  11. Two wheel speed robust sliding mode control for electric vehicle drive

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    Abdelfatah Nasri

    2008-01-01

    Full Text Available Nowadays the uses of electrical power resources are integrated in the modern vehicle motion traction chain so new technologies allow the development of electric vehicles (EV by means of static converters-related electric motors. All mechanical transmission devices are eliminated and vehicle wheel motion can be controlled by means of power electronics. The proposed propulsing system consists of two induction motors (IM that ensure the drive of the two back driving wheels. The proposed control structure-called independent machines- for speed control permit the achievement of an electronic differential. The electronic differential system ensures the robust control of the vehicle behavior on the road. It also allows controlling independently, every driving wheel to turn at different speeds in any curve. This paper presents the study and the sliding mode control strategy of the electric vehicle driving wheels.

  12. Sliding mode control of direct coupled interleaved boost converter for fuel cell

    Science.gov (United States)

    Wang, W. Y.; Ding, Y. H.; Ke, X.; Ma, X.

    2017-12-01

    A three phase direct coupled interleaved boost converter (TP-DIBC) was recommended in this paper. This converter has a small unbalance current sharing among the branches of TP-DIBC. An adaptive control law sliding mode control (SMC) is designed for the TP-DIBC. The aim is to 1) reduce ripple output voltage, inductor current and regulate output voltage tightly 2) The total current carried by direct coupled interleaved boost converter (DIBC) must be equally shared between different parallel branches. The efficacy and robustness of the proposed TP-DIBC and adaptive SMC is confirmed via computer simulations using Matlab SimPower System Tools. The simulation result is in line with the expectation.

  13. Sliding Mode Control for Mass Moment Aerospace Vehicles Using Dynamic Inversion Approach

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    Xiao-Yu Zhang

    2013-01-01

    Full Text Available The moving mass actuation technique offers significant advantages over conventional aerodynamic control surfaces and reaction control systems, because the actuators are contained entirely within the airframe geometrical envelope. Modeling, control, and simulation of Mass Moment Aerospace Vehicles (MMAV utilizing moving mass actuators are discussed. Dynamics of the MMAV are separated into two parts on the basis of the two time-scale separation theory: the dynamics of fast state and the dynamics of slow state. And then, in order to restrain the system chattering and keep the track performance of the system by considering aerodynamic parameter perturbation, the flight control system is designed for the two subsystems, respectively, utilizing fuzzy sliding mode control approach. The simulation results describe the effectiveness of the proposed autopilot design approach. Meanwhile, the chattering phenomenon that frequently appears in the conventional variable structure systems is also eliminated without deteriorating the system robustness.

  14. Research on Sliding Mode Control for Steer-by-Wire System in Forklift

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    Huang Jun-Jie

    2017-01-01

    Full Text Available Aiming at steering stability and wheel angle tracking of steer-by-wire (SBW three wheeled forklift, steering dynamic model and SBW system mathematical model of three wheeled forklift are established. A control strategy for the ideal transmission ratio is introduced based on this model, which ensures forklift steering gain invariant. A sliding mode controller can then be designed based on the bound information of uncertain system parameters, uncertain self-aligning torque, and external disturbances. The results of simulation show the control strategies above can effectively reduce the sideslip angle when the forklift is steering and improve the sensitivity and stability of the steering forklift; at the same time can effectively restrain the parameter perturbation of internal system and external disturbance, which improves the tracking performance of the wheel angle.

  15. Dynamic Analysis and Adaptive Sliding Mode Controller for a Chaotic Fractional Incommensurate Order Financial System

    Science.gov (United States)

    Hajipour, Ahmad; Tavakoli, Hamidreza

    2017-12-01

    In this study, the dynamic behavior and chaos control of a chaotic fractional incommensurate-order financial system are investigated. Using well-known tools of nonlinear theory, i.e. Lyapunov exponents, phase diagrams and bifurcation diagrams, we observe some interesting phenomena, e.g. antimonotonicity, crisis phenomena and route to chaos through a period doubling sequence. Adopting largest Lyapunov exponent criteria, we find that the system yields chaos at the lowest order of 2.15. Next, in order to globally stabilize the chaotic fractional incommensurate order financial system with uncertain dynamics, an adaptive fractional sliding mode controller is designed. Numerical simulations are used to demonstrate the effectiveness of the proposed control method.

  16. Sliding mode disturbance observer-enhanced adaptive control for the air-breathing hypersonic flight vehicle

    Science.gov (United States)

    An, Hao; Wang, Changhong; Fidan, Baris

    2017-10-01

    This paper presents a backstepping procedure to design an adaptive controller for the air-breathing hypersonic flight vehicle (AHFV) subject to external disturbances and actuator saturations. In each step, a sliding mode exact disturbance observer (SMEDO) is exploited to exactly estimate the lumped disturbance in finite time. Specific dynamics are introduced to handle the possible actuator saturations. Based on SMEDO and introduced dynamics, an adaptive control law is designed, along with the consideration on ;explosion of complexity; in backstepping design. The developed controller is equipped with fast disturbance rejection and great capability to accommodate the saturated actuators, which also lead to a wider application scope. A simulation study is provided to show the effectiveness and superiority of the proposed controller.

  17. A Global Sliding-Mode Control Scheme with Adjustable Robustness for A Linear Variable Reluctance Motor

    Science.gov (United States)

    Lin, Jin-Yuan; Lu, Yu-Sheng; Chen, Jian-Shiang

    A novel global sliding-mode control (GSMC) scheme with adjustable robustness is presented in this article. The proposed scheme offers a switching function together with unperturbed system dynamics to weigh the contribution from SMC such that all of the closed-loop poles can be located within predefined regions to provide design flexibility, and the robustness of system can thus be adjusted. By this scheme, the maximal control effort and chattering level can be reduced according to designer's specifications directly. Since the switching function can initially be made to equal to zero, the adjustable performance during the entire response can be guaranteed, and the reaching condition is thus lifted. The efficacy of this scheme is demonstrated via successful implementation on a linear variable reluctance motor (LVRM) servo system. Both simulation and experimental studies further demonstrate its feasibility and effectiveness.

  18. Direct Torque Control of Sensorless Induction Motor Drives: A Sliding-Mode Approach

    DEFF Research Database (Denmark)

    Lascu, Cristian; Boldea, Ion; Blaabjerg, Frede

    2004-01-01

    Direct torque control (DTC) is known to produce fast response and robust control in ac adjustable-speed drives. However, in the steady-state operation, notable torque, flux, and current pulsations occur. A new, direct torque and flux control strategy based on variable-structure control and space-vector...... pulsewidth modulation is proposed for induction motor sensorless drives. The DTC transient merits and robustness are preserved and the steady-state behaviour is improved by reducing the torque and flux pulsations. A sliding-mode observer using a dual reference frame motor model is introduced and tested....... Simulations and comparative experimental results with the proposed control scheme, versus classic DTC, are presented. Very-low-speed sensorless operation (3 r/min) is demonstrated....

  19. Fault Reconstruction Based on Sliding Mode Observer for Current Sensors of PMSM

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    Changfan Zhang

    2016-01-01

    Full Text Available This paper deals with a method of phase current sensor fault reconstruction for permanent magnet synchronous motor (PMSM drives. A new state variable is introduced so that an augmented system can be constructed to treat PMSM sensor faults as actuator faults. This method uses the PMSM two-phase stationary reference frame fault model and a sliding mode variable structure observer to reconstruct fault signals. A logic algorithm is built to isolate and identify the faulty sensor for a stator phase current fault after reconstructing the two-phase stationary reference frame fault signals, which allows the phase fault signals to be reconstructed. Simulation results are presented to illustrate the functionality of the theoretical developments.

  20. Speed tracking and synchronization of multiple motors using ring coupling control and adaptive sliding mode control.

    Science.gov (United States)

    Li, Le-Bao; Sun, Ling-Ling; Zhang, Sheng-Zhou; Yang, Qing-Quan

    2015-09-01

    A new control approach for speed tracking and synchronization of multiple motors is developed, by incorporating an adaptive sliding mode control (ASMC) technique into a ring coupling synchronization control structure. This control approach can stabilize speed tracking of each motor and synchronize its motion with other motors' motion so that speed tracking errors and synchronization errors converge to zero. Moreover, an adaptive law is exploited to estimate the unknown bound of uncertainty, which is obtained in the sense of Lyapunov stability theorem to minimize the control effort and attenuate chattering. Performance comparisons with parallel control, relative coupling control and conventional PI control are investigated on a four-motor synchronization control system. Extensive simulation results show the effectiveness of the proposed control scheme. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  1. High performance fuzzy sliding mode control of DFIG supplied by seven level NPC inverter

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    Mohamed BENKAHLA

    2017-09-01

    Full Text Available This article presents the powers control of a variable speed wind turbine (WT based on a doubly fed induction generator (DFIG because of their advantages in terms of economy and control. The considered system consists of a double fed induction generator whose stator is connected directly to the network and its rotor is supplied by seven-level inverter with structure NPC are well used to minimize the harmonics absorbed by the DFIG. In order to control the power flowing between the stator of the DFIG and the grid. Have been studied and compared two types of controllers : Sliding Mode Control (SMC and Fuzzy SMC (FSMC. Their respective performances are compared in terms of power reference tracking, response to sudden speed variations, sensitivity to perturbations and robustness against machine parameters variations.

  2. Speed Synchronization of Multi Induction Motors with Fuzzy Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    HACHEMI Glaoui

    2013-05-01

    Full Text Available A continuous web winding system is a large-scale, complex interconnected dynamic system with numerous tension zones to transport the web while processing it. There are two control schemes for large-scale system control: the centralized scheme and the decentralized scheme. Centralized control is the traditional control method, which considers all the information about the system to be a single dynamic model and design a control system for this model. Aspeed synchronization control strategy for multiple induction motors, based on adjacent cross-coupling control structure, is developed by employing total sliding mode control method. The proposed controlstrategy is to stabilize speed tracking of each induction motor while synchronizing its speed with the speed of the other motors so as to make speed synchronization error amongst induction motors converge to zero. The global stability and the convergence of the designedcontroller are proved by using Lyapunov method. Simulation results demonstrate the effectiveness of the proposed method.

  3. Comparative Study on Photovoltaic Pumping Systems Driven by Different Motors Optimized with Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Abdelhak Bouchakour

    2017-06-01

    Full Text Available This study investigates the performance of three different photovoltaic (PV water pumping systems driven by three types of motors, namely a separately excited DC motor (DCM, an asynchronous motor (ASM, and a permanent magnet synchronous motor (PMSM, via a DC/DC buck-boost converter coupled to a centrifugal pump. The purpose of this study is to implement a fast and robust control for this type of a nonlinear system, controlled by sliding mode (SM. This paper presents an SM control technique for controlling a DC/DC buck-boost converter to transfer the maximum power delivered by the PV generator. Each component is studied and analyzed to simulate the global system in MATLAB/SIMULINK. The three systems are then compared to determine the overall effectiveness of the proposed command. The study concludes that the ASM-driven PV system yields highly favorable results and requires less maintenance compared with other systems.

  4. High-order sliding mode observer for fractional commensurate linear systems with unknown input

    KAUST Repository

    Belkhatir, Zehor

    2017-05-20

    In this paper, a high-order sliding mode observer (HOSMO) is proposed for the joint estimation of the pseudo-state and the unknown input of fractional commensurate linear systems with single unknown input and a single output. The convergence of the proposed observer is proved using a Lyapunov-based approach. In addition, an enhanced variant of the proposed fractional-HOSMO is introduced to avoid the peaking phenomenon and thus to improve the estimation results in the transient phase. Simulation results are provided to illustrate the performance of the proposed fractional observer in both noise-free and noisy cases. The effect of the observer’s gains on the estimated pseudo-state and unknown input is also discussed.

  5. Air-fuel ratio and speed control for low emission vehicles based on sliding mode techniques

    Energy Technology Data Exchange (ETDEWEB)

    Puleston, P.F. [UNLP, La Plata (Argentina). Departamento de Electrotecnia, CONICET and LEICI; Monsees, G. [Delft University of Technology (Netherlands). Faculty of Information, Technology and Systems, Control Laboratory; Spurgeon, S.K. [University of Leicester (United Kingdom). Department of Engineering, Control and Instrumentation Group

    2002-05-01

    This paper deals with the combined air-fuel ratio (AFR) and speed control of automotive engines. The robust controller is developed using dynamic sliding mode (SM) control design methods. The proposed controller set-up is tested under realistic operating conditions by means of computer simulation using a comprehensive non-linear model of a four-stroke engine, specifically provided by the automotive industry for these purposes. This accurate industrial model comprises extensive dynamics description and numerous look-up tables representing parameter characteristics obtained from experimental data. The SM controller set-up proves to be robust to model uncertainties and unknown disturbances, regulating effectively the engine speed for a wide range of set-points while maintaining the AFR at the stoichiometric value. (author)

  6. Fractional Order Memristor No Equilibrium Chaotic System with Its Adaptive Sliding Mode Synchronization and Genetically Optimized Fractional Order PID Synchronization

    Directory of Open Access Journals (Sweden)

    Karthikeyan Rajagopal

    2017-01-01

    Full Text Available This paper introduces a fractional order memristor no equilibrium (FOMNE chaotic system and investigates its adaptive sliding mode synchronization. Firstly the dynamic properties of the integer order memristor no equilibrium system are analyzed. The fractional order memristor no equilibrium system is then derived from the integer order model. Lyapunov exponents and bifurcation with fractional order are investigated. An adaptive sliding mode control algorithm is derived to globally synchronize the identical fractional order memristor systems and genetically optimized fractional order PID controllers are designed and used to synchronize the FOMNE systems. Finally the fractional order memristor no equilibrium system is realized using FPGA.

  7. A 0.35μm 50V CMOS Sliding-Mode Control IC for Buck Converters

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.; Andreani, Pietro

    2007-01-01

    This paper presents a hysteretic (sliding mode) control IC for a buck DC/DC converter for use as an envelope tracking power supply to increase the efficiency of an RF power amplifier. The IC integrates a high-bandwidth error amplifier, a comparator with hysteresis, and a high-side driver for an e......This paper presents a hysteretic (sliding mode) control IC for a buck DC/DC converter for use as an envelope tracking power supply to increase the efficiency of an RF power amplifier. The IC integrates a high-bandwidth error amplifier, a comparator with hysteresis, and a high-side driver...

  8. Robust Stability for Nonlinear Systems with Time-Varying Delay and Uncertainties via the H∞ Quasi-Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Yi-You Hou

    2014-01-01

    Full Text Available This paper considers the problem of the robust stability for the nonlinear system with time-varying delay and parameters uncertainties. Based on the H∞ theorem, Lyapunov-Krasovskii theory, and linear matrix inequality (LMI optimization technique, the H∞ quasi-sliding mode controller and switching function are developed such that the nonlinear system is asymptotically stable in the quasi-sliding mode and satisfies the disturbance attenuation (H∞-norm performance. The effectiveness and accuracy of the proposed methods are shown in numerical simulations.

  9. Slide 1

    Indian Academy of Sciences (India)

    Click here to start. Table of contents. Slide 1 · Slide 2 · Slide 3 · Slide 4 · Slide 5 · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Slide 15 · Slide 16 · Slide 17.

  10. Adaptive Sliding Mode Control of Mobile Manipulators with Markovian Switching Joints

    Directory of Open Access Journals (Sweden)

    Liang Ding

    2012-01-01

    Full Text Available The hybrid joints of manipulators can be switched to either active (actuated or passive (underactuated mode as needed. Consider the property of hybrid joints, the system switches stochastically between active and passive systems, and the dynamics of the jump system cannot stay on each trajectory errors region of subsystems forever; therefore, it is difficult to determine whether the closed-loop system is stochastically stable. In this paper, we consider stochastic stability and sliding mode control for mobile manipulators using stochastic jumps switching joints. Adaptive parameter techniques are adopted to cope with the effect of Markovian switching and nonlinear dynamics uncertainty and follow the desired trajectory for wheeled mobile manipulators. The resulting closed-loop system is bounded in probability and the effect due to the external disturbance on the tracking errors can be attenuated to any preassigned level. It has been shown that the adaptive control problem for the Markovian jump nonlinear systems is solvable if a set of coupled linear matrix inequalities (LMIs have solutions. Finally, a numerical example is given to show the potential of the proposed techniques.

  11. Analysis of rotational and sliding collapse modes of masonry arches via Durand-Claye's method

    Science.gov (United States)

    Barsotti, Riccardo; Aita, Danila; Bennati, Stefano

    2017-11-01

    In this paper the mechanical behavior of circular and pointed masonry arches subject to their own weight is examined in order to determine their collapse modes. Different arch's shapes and thicknesses are considered; the influence of the friction coefficient on the arch collapse is analyzed as well. The safety level of arches is investigated by suitably reworking in semi-analytical form the stability area graphical method proposed by a renowned 19th century French scholar, Durand-Claye. Our analysis enables accounting for any given eccentricity of the thrust at the crown; furthermore, also the strength of masonry is taken into account. According to Durand-Claye's method, the arch is safe if along any given joint both the bending moment and the shear force do not exceed some given limit values. It is shown that attainment of a limit condition according to Durand-Claye corresponds to the onset of a collapse mechanism characterized by either relative rotation or sliding between masonry units. All possible symmetric collapse modes for an arch are thoroughly described. As it was expected, pointed and circular arches show different collapse behaviors. Limit values of arch thickness and friction coefficient are assessed. The results obtained are compared with those given by Michon in 1857.

  12. A Class of Speed-Sensorless Sliding-Mode Observers for High-Performance Induction Motor Drives

    DEFF Research Database (Denmark)

    Lascu, Christian; Boldea, Ion; Blaabjerg, Frede

    2009-01-01

    A new family of speed-sensorless sliding-mode observers for induction motor drives has been developed. Three topologies are investigated in order to determine their feasibility, parameter sensitivity, and practical applicability. The most significant feature of all schemes is that they do...

  13. Extended Kalman Filter Based Sliding Mode Control of Parallel-Connected Two Five-Phase PMSM Drive System

    Directory of Open Access Journals (Sweden)

    Tounsi Kamel

    2018-01-01

    Full Text Available This paper presents sliding mode control of sensor-less parallel-connected two five-phase permanent magnet synchronous machines (PMSMs fed by a single five-leg inverter. For both machines, the rotor speeds and rotor positions as well as load torques are estimated by using Extended Kalman Filter (EKF scheme. Fully decoupled control of both machines is possible via an appropriate phase transposition while connecting the stator windings parallel and employing proposed speed sensor-less method. In the resulting parallel-connected two-machine drive, the independent control of each machine in the group is achieved by controlling the stator currents and speed of each machine under vector control consideration. The effectiveness of the proposed Extended Kalman Filter in conjunction with the sliding mode control is confirmed through application of different load torques for wide speed range operation. Comparison between sliding mode control and PI control of the proposed two-motor drive is provided. The speed response shows a short rise time, an overshoot during reverse operation and settling times is 0.075 s when PI control is used. The speed response obtained by SMC is without overshoot and follows its reference and settling time is 0.028 s. Simulation results confirm that, in transient periods, sliding mode controller remarkably outperforms its counterpart PI controller.

  14. Slide 1

    Indian Academy of Sciences (India)

    Slide 5 · Slide 6 · Slide 7 · Immunology of VL · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Strategies To Design Drugs · Slide 16 · Slide 17 · Slide 18 · Slide 19 · Slide 20 · Slide 21 · Slide 22 · Slide 23 · Slide 24 · Slide 25 · Slide 26 · Slide 27 · Slide 28 · Slide 29 · Slide 30 · Slide 31 · Slide 32 · Slide 33 · Slide 34.

  15. Slide 1

    Indian Academy of Sciences (India)

    Gene Expression in Eukaryotic Cells · Slide 3 · Slide 4 · Slide 5 · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Slide 15 · Slide 16 · Slide 17 · Slide 18 · Slide 19 · Slide 20 · Slide 21 · Slide 22 · Slide 23 · Slide 24 · Slide 25 · Slide 26 · Slide 27 · Slide 28 · Slide 29. Author: Office.

  16. Geometric-attributes-based segmentation of cortical bone slides using optimized neural networks.

    Science.gov (United States)

    Hage, Ilige S; Hamade, Ramsey F

    2016-05-01

    In cortical bone, solid (lamellar and interstitial) matrix occupies space left over by porous microfeatures such as Haversian canals, lacunae, and canaliculi-containing clusters. In this work, pulse-coupled neural networks (PCNN) were used to automatically distinguish the microfeatures present in histology slides of cortical bone. The networks' parameters were optimized using particle swarm optimization (PSO). When forming the fitness functions for the PSO, we considered the microfeatures' geometric attributes-namely, their size (based on measures of elliptical perimeter or area), shape (based on measures of compactness or the ratio of minor axis length to major axis length), and a two-way combination of these two geometric attributes. This hybrid PCNN-PSO method was further enhanced for pulse evaluation by combination with yet another method, adaptive threshold (AT), where the PCNN algorithm is repeated until the best threshold is found corresponding to the maximum variance between two segmented regions. Together, this framework of using PCNN-PSO-AT constitutes, we believe, a novel framework in biomedical imaging. Using this framework and extracting microfeatures from only one training image, we successfully extracted microfeatures from other test images. The high fidelity of all resultant segments was established using quantitative metrics such as precision, specificity, and Dice indices.

  17. Robustness and Actuator Bandwidth of MRP-Based Sliding Mode Control for Spacecraft Attitude Control Problems

    Science.gov (United States)

    Keum, Jung-Hoon; Ra, Sung-Woong

    2009-12-01

    Nonlinear sliding surface design in variable structure systems for spacecraft attitude control problems is studied. A robustness analysis is performed for regular form of system, and calculation of actuator bandwidth is presented by reviewing sliding surface dynamics. To achieve non-singular attitude description and minimal parameterization, spacecraft attitude control problems are considered based on modified Rodrigues parameters (MRP). It is shown that the derived controller ensures the sliding motion in pre-determined region irrespective of unmodeled effects and disturbances.

  18. Optimized color decomposition of localized whole slide images and convolutional neural network for intermediate prostate cancer classification

    Science.gov (United States)

    Zhou, Naiyun; Gao, Yi

    2017-03-01

    This paper presents a fully automatic approach to grade intermediate prostate malignancy with hematoxylin and eosin-stained whole slide images. Deep learning architectures such as convolutional neural networks have been utilized in the domain of histopathology for automated carcinoma detection and classification. However, few work show its power in discriminating intermediate Gleason patterns, due to sporadic distribution of prostate glands on stained surgical section samples. We propose optimized hematoxylin decomposition on localized images, followed by convolutional neural network to classify Gleason patterns 3+4 and 4+3 without handcrafted features or gland segmentation. Crucial glands morphology and structural relationship of nuclei are extracted twice in different color space by the multi-scale strategy to mimic pathologists' visual examination. Our novel classification scheme evaluated on 169 whole slide images yielded a 70.41% accuracy and corresponding area under the receiver operating characteristic curve of 0.7247.

  19. Adaptive Second Order Sliding Mode Control of a Fuel Cell Hybrid System for Electric Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Jianxing Liu

    2015-01-01

    Full Text Available We present an adaptive-gain second order sliding mode (SOSM control applied to a hybrid power system for electric vehicle applications. The main advantage of the adaptive SOSM is that it does not require the upper bound of the uncertainty. The proposed hybrid system consists of a polymer electrolyte membrane fuel cell (PEMFC with a unidirectional DC/DC converter and a Li-ion battery stack with a bidirectional DC/DC converter, where the PEMFC is employed as the primary energy source and the battery is employed as the second energy source. One of the main limitations of the FC is its slow dynamics mainly due to the air-feed system and fuel-delivery system. Fuel starvation phenomenon will occur during fast load demand. Therefore, the second energy source is required to assist the main source to improve system perofrmance. The proposed energy management system contains two cascade control structures, which are used to regulate the fuel cell and battery currents to track the given reference currents and stabilize the DC bus voltage while satisfying the physical limitations. The proposed control strategy is evaluated for two real driving cycles, that is, Urban Dynamometer Driving Schedule (UDDS and Highway Fuel Economy Driving Schedule (HWFET.

  20. Closed-Loop Input Shaping Control of Vibration in Flexible Structures via Adaptive Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Ming-Chang Pai

    2012-01-01

    Full Text Available Input shaping technique is widely used in reducing or eliminating residual vibration of flexible structures. The exact elimination of the residual vibration via input shaping technique depends on the amplitudes and instants of impulse application. However, systems always have parameter uncertainties which can lead to performance degradation. In this paper, a closed-loop input shaping control scheme is developed for uncertain flexible structures. The algorithm is based on input shaping control and adaptive sliding mode control. The proposed scheme does not need a priori knowledge of upper bounds on the norm of the uncertainties, but estimates them by using the adaptation technique. This scheme guarantees closed-loop system stability, and yields good performance and robustness in the presence of parameter uncertainties and external disturbances as well. Furthermore, it is shown that increasing the robustness to parameter uncertainties does not lengthen the duration of the impulse sequence. Simulation results demonstrate the efficacy of the proposed closed-loop input shaping control scheme.

  1. State observer-based sliding mode control for semi-active hydro-pneumatic suspension

    Science.gov (United States)

    Ren, Hongbin; Chen, Sizhong; Zhao, Yuzhuang; Liu, Gang; Yang, Lin

    2016-02-01

    This paper proposes an improved virtual reference model for semi-active suspension to coordinate the vehicle ride comfort and handling stability. The reference model combines the virtues of sky-hook with ground-hook control logic, and the hybrid coefficient is tuned according to the longitudinal and lateral acceleration so as to improve the vehicle stability especially in high-speed condition. Suspension state observer based on unscented Kalman filter is designed. A sliding mode controller (SMC) is developed to track the states of the reference model. The stability of the SMC strategy is proven by means of Lyapunov function taking into account the nonlinear damper characteristics and sprung mass variation of the vehicle. Finally, the performance of the controller is demonstrated under three typical working conditions: the random road excitation, speed bump road and sharp acceleration and braking. The simulation results indicated that, compared with the traditional passive suspension, the proposed control algorithm can offer a better coordination between vehicle ride comfort and handling stability. This approach provides a viable alternative to costlier active suspension control systems for commercial vehicles.

  2. Robust Sliding Mode Control of Air Handling Unit for Energy Efficiency Enhancement

    Directory of Open Access Journals (Sweden)

    Awais Shah

    2017-11-01

    Full Text Available In order to achieve feasible and copacetic low energy consuming building, a robust and efficient air conditioning system is necessary. Since heating ventilation and air conditioning systems are nonlinear and temperature and humidity are coupled, application of conventional control is inappropriate. A multi-input multi-output nonlinear model is presented. The temperature and humidity of thermal zone are ascendance by the manipulation of the water and air flow rates. A sliding mode controller (SMC is designed to ensure robust performance of air handling unit in the presence of uncertainties. A simple proportional-integral-derivative (PID controller is used as a comparison template to highlight the efficiency of the proposed controller. To accomplish tracking targets, a variety of desired temperature and relative humidity commands (including ramp and combination with sequence of steps are investigated. According to simulation results, SMC transcends the PID controller in terms of settling time, steady state and rise time, which makes SMC more energy efficient.

  3. Robust tracking control of an IPMC actuator using nonsingular terminal sliding mode

    Science.gov (United States)

    Khawwaf, Jasim; Zheng, Jinchuan; Lu, Renquan; Al-Ghanimi, Ali; Kazem, Bahaa I.; Man, Zhihong

    2017-09-01

    Ionic polymer metal composite (IPMC) is a highly innovative material that has recently gained attention in many fields such as medical, biomimetic, and micro/nano underwater applications. The main characteristic of IPMC lies in its ability to achieve a large deflection under a fairly low driving voltage. Moreover, its agile, light weight, noiseless and flexible features render it well suited for certain specific applications. Like other smart materials, such as piezoelectric ceramics, IPMC could be used in actuators or sensors. In this paper, we study the application of IPMC as an actuator for underwater use. The goal is to develop a robust feedback controller for the IPMC actuator to track a desired reference whilst dealing with the uncertainties due to the inherent actuator nonlinearity, external disturbance or the variations of working environment. To this end, we first present a nominal model of the IPMC actuator through experimental identification. Next, a nonsingular terminal sliding mode controller is proposed. Lastly, experimental studies are conducted to verify the tracking accuracy and robustness of the designed controller.

  4. Adaptive sliding mode control of the A-axis used for blisk manufacturing

    Directory of Open Access Journals (Sweden)

    Zhao Pengbing

    2014-06-01

    Full Text Available As a key assembly in the 5-axis CNC machine tools, positioning precision of the A-axis directly affects the machining accuracy and surface quality of the parts. First of all, mechanical structure and control system of the A-axis are designed. Then, considering the influence of nonlinear friction, backlash, unmodeled dynamics, uncertain cutting force and other external disturbance on the control precision of the A-axis, an adaptive sliding mode control (ASMC based on extended state observer (ESO is proposed. ESO is employed to estimate the state variables of the unknown system and an adaptive law is adopted to compensate for the input dead-zone caused by friction, backlash and other nonlinear characteristics. Finally, stability of the closed-loop system is guaranteed by the Lyapunov theory. Positioning experiments illustrate the perfect estimation of ESO and the stronger anti-interference and robustness of ASMC, which can improve the control precision of the A-axis by about 40 times. Processing experiments show that the ASMC can reduce the waviness, average error and roughness of the processed surface by 35.63%, 31.31% and 30.35%, respectively.

  5. LQ optimal and reaching law-based sliding modes for inventory management systems

    Science.gov (United States)

    Ignaciuk, Przemysław; Bartoszewicz, Andrzej

    2012-01-01

    In this article, the theory of discrete sliding-mode control is used to design new supply strategies for periodic-review inventory systems. In the considered systems, the stock used to fulfil an unknown, time-varying demand can be replenished from a single supply source or from multiple suppliers procuring orders with different delays. The proposed strategies guarantee that demand is always entirely satisfied from the on-hand stock (yielding the maximum service level), and the warehouse capacity is not exceeded (which eliminates the cost of emergency storage). In contrast to the classical, stochastic approaches, in this article, we focus on optimising the inventory system dynamics. The parameters of the first control strategy are selected by minimising a quadratic cost functional. Next, it is shown how the system dynamical performance can be improved by applying the concept of a reaching law with the appropriately adjusted reaching phase. The stable, nonoscillatory behaviour of the closed-loop system is demonstrated and the properties of the designed controllers are discussed and strictly proved.

  6. Sliding Mode Pulsed Averaging IC Drivers for High Brightness Light Emitting Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Anatoly Shteynberg, PhD

    2006-08-17

    This project developed new Light Emitting Diode (LED) driver ICs associated with specific (uniquely operated) switching power supplies that optimize performance for High Brightness LEDs (HB-LEDs). The drivers utilize a digital control core with a newly developed nonlinear, hysteretic/sliding mode controller with mixed-signal processing. The drivers are flexible enough to allow both traditional microprocessor interface as well as other options such as “on the fly” adjustment of color and brightness. Some other unique features of the newly developed drivers include • AC Power Factor Correction; • High power efficiency; • Substantially fewer external components should be required, leading to substantial reduction of Bill of Materials (BOM). Thus, the LED drivers developed in this research : optimize LED performance by increasing power efficiency and power factor. Perhaps more remarkably, the LED drivers provide this improved performance at substantially reduced costs compared to the present LED power electronic driver circuits. Since one of the barriers to market penetration for HB-LEDs (in particular “white” light LEDs) is cost/lumen, this research makes important contributions in helping the advancement of SSL consumer acceptance and usage.

  7. A Double-Wing Chaotic System Based on Ion Migration Memristor and Its Sliding Mode Control

    Science.gov (United States)

    Min, Guoqi; Duan, Shukai; Wang, Lidan

    The ion migration memristor is a nonlinear element with memory function and nanoscale size, it is considered as a potential candidate to reduce system power consumption and circuit size. When it works as the nonlinear part of the chaotic system, rich nonlinear curves will be produced, and at the same time, the complexity of chaotic systems and the randomness of signals will be enhanced. So in this paper, by Matlab numerical simulation, a new double-wing chaotic system based on an ion migration memristor is designed. In reality, there are many systems interfered inevitably by random noise, so in this paper the random bounded noises are also considered. The power spectrum, Lyapunov exponent spectrum, Poincaré map and bifurcation diagram are used to investigate its complex dynamic characteristics. Then, a SPICE-based analog circuit is presented to verify the feasibility of the system, for which the simulation results are consistent with the numerical simulation. Finally, the sliding mode variable structure control is applied to overcome the shortcomings of traditional control method, so that the chaotic orbits can be controlled to any fixed points or periodic orbits, and this provides an insight into chaos control in power electronics systems.

  8. Passive impedance-based second-order sliding mode control for non-linear teleoperators

    Directory of Open Access Journals (Sweden)

    Luis G García-Valdovinos

    2017-02-01

    Full Text Available Bilateral teleoperation systems have attracted significant attention in the last decade mainly because of technological advancements in both the communication channel and computers performance. In addition, non-linear multi-degree-of-freedom bilateral teleoperators along with state observers have become an open research area. In this article, a model-free exact differentiator is used to estimate the full state along with a chattering-free second-order sliding mode controller to guarantee a robust impedance tracking under both constant and an unknown time delay of non-linear multi-degree-of-freedom robots. The robustness of the proposed controller is improved by introducing a change of coordinates in terms of a new nominal reference similar to that used in adaptive control theory. Experimental results that validate the predicted behaviour are presented and discussed using a Phantom Premium 1.0 as the master robot and a Catalyst-5 virtual model as the slave robot. The dynamics of the Catalyst-5 system is solved online.

  9. Robust Adaptive Sliding Mode Consensus of Multiagent Systems with Perturbed Communications and Actuators

    Directory of Open Access Journals (Sweden)

    Xiao-Zheng Jin

    2013-01-01

    Full Text Available This paper deals with the asymptotic consensus problem for a class of multiagent systems with time-varying additive actuator faults and perturbed communications. The L2 performance of systems is also considered in the consensus controller designs. The upper and lower bounds of faults and perturbations in actuators and communications and controller gains are assumed to be unknown but can be estimated by designing some indirect adaptive laws. Based on the information from the adaptive estimation mechanism, the distributed robust adaptive sliding mode controllers are constructed to automatically compensate for the effects of faults and perturbations and to achieve any given level of L2 gain attenuation from external disturbance to consensus errors. Through Lyapunov functions and adaptive schemes, the asymptotic consensus of resulting adaptive multiagent system can be achieved with a specified performance criterion in the presence of perturbed communications and actuators. The effectiveness of the proposed design is illustrated via a decoupled longitudinal model of F-18 aircraft.

  10. Global fast dynamic terminal sliding mode control for a quadrotor UAV.

    Science.gov (United States)

    Xiong, Jing-Jing; Zhang, Guo-Bao

    2017-01-01

    A control method based on global fast dynamic terminal sliding mode control (TSMC) technique is proposed to design the flight controller for performing the finite-time position and attitude tracking control of a small quadrotor UAV. Firstly, the dynamic model of the quadrotor is divided into two subsystems, i.e., a fully actuated subsystem and an underactuated subsystem. Secondly, the dynamic flight controllers of the quadrotor are formulated based on global fast dynamic TSMC, which is able to guarantee that the position and velocity tracking errors of all system state variables converge to zero in finite-time. Moreover, the global fast dynamic TSMC is also able to eliminate the chattering phenomenon caused by the switching control action and realize the high precision performance. In addition, the stabilities of two subsystems are demonstrated by Lyapunov theory, respectively. Lastly, the simulation results are given to illustrate the effectiveness and robustness of the proposed control method in the presence of external disturbances. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Vehicle Sliding Mode Control with Adaptive Upper Bounds: Static versus Dynamic Allocation to Saturated Tire Forces

    Directory of Open Access Journals (Sweden)

    Ali Tavasoli

    2012-01-01

    Full Text Available Nonlinear vehicle control allocation is achieved through distributing the task of vehicle control among individual tire forces, which are constrained to nonlinear saturation conditions. A high-level sliding mode control with adaptive upper bounds is considered to assess the body yaw moment and lateral force for the vehicle motion. The proposed controller only requires the online adaptation of control gains without acquiring the knowledge of upper bounds on system uncertainties. Static and dynamic control allocation approaches have been formulated to distribute high-level control objectives among the system inputs. For static control allocation, the interior-point method is applied to solve the formulated nonlinear optimization problem. Based on the dynamic control allocation method, a dynamic update law is derived to allocate vehicle control to tire forces. The allocated tire forces are fed into a low-level control module, where the applied torque and active steering angle at each wheel are determined through a slip-ratio controller and an inverse tire model. Computer simulations are used to prove the significant effects of the proposed control allocation methods on improving the stability and handling performance. The advantages and limitations of each method have been discussed, and conclusions have been derived.

  12. Transparent Higher Order Sliding Mode Control for Nonlinear Master-Slave Systems without Velocity Measurement

    Directory of Open Access Journals (Sweden)

    Luis G. Garcia-Valdovinos

    2015-04-01

    Full Text Available Transparency has been a major objective in bilateral teleoperation systems, even in the absence of time delay induced by the communication channel, since a high degree of transparency would allow humans to drive the remote teleoperator as if he or she were directly interacting with the remote environment, with the remote teleoperator as a physical and sensorial extension of the operator. When fast convergence of position and force tracking errors are ensured by the control system, then complete transparency is obtained, which would ideally guarantee humans to be tightly kinaesthetically coupled. In this paper a model-free Cartesian second order sliding mode (SOSM PD control scheme for nonlinear master-slave systems is presented. The proposed scheme does not rely on velocity measurements and attains very fast convergence of position trajectories, with bounded tracking of force trajectories, rendering a high degree of transparency with lesser knowledge of the system. The degree of transparency can easily be improved by tuning a feedback gain in the force loop. A unique energy storage function is introduced; such that a similar Cartesian-based controller is implemented in the master and slave sides. The resulting properties of the Cartesian control structure allows the human operator to input directly Cartesian variables, which makes clearer the kinaesthetic coupling, thus the proposed controller becomes a suitable candidate for practical implementation. The performance of the proposed scheme is evaluated in a semi-experimental setup.

  13. Slide 1

    Indian Academy of Sciences (India)

    Slide 5 · Slide 6 · Second Question How Did this Shift in ToT Come About? Slide 8 · Second Question How Did this Shift in ToT Come About? Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Slide 15 · Slide 17 · Slide 20 · Slide 21 · Slide 22 · Slide 23 · Slide 24 · Slide 25 · Slide 26 · Slide 27 · Slide 30 · India's Globalization.

  14. A New Fast Nonsingular Terminal Sliding Mode Control for a Class of Second-Order Uncertain Systems

    Directory of Open Access Journals (Sweden)

    Linjie Xin

    2016-01-01

    Full Text Available This paper considers the robust and adaptive nonsingular terminal sliding mode (NTSM control for a class of second-order uncertain systems. First, a new fast NTSM was proposed which had global fast convergence rate in the sliding phase. Then, a new form of robust NTSM controller was designed to handle a wider class of second-order uncertain systems. Moreover, an exponential-decline switching gain was introduced for chattering suppression. After that, a double sliding surfaces control scheme was constructed to combine the NTSM control with the adaptive technique. The benefit is that a strict demonstration can be given for the stagnation problem in the stability analysis of NTSM. Finally, a case study for tracking control of a variable-length pendulum was performed to verify the proposed controllers.

  15. Control of equipment isolation system using wavelet-based hybrid sliding mode control

    Science.gov (United States)

    Huang, Shieh-Kung; Loh, Chin-Hsiung

    2017-04-01

    Critical non-structural equipment, including life-saving equipment in hospitals, circuit breakers, computers, high technology instrumentations, etc., is vulnerable to strong earthquakes, and on top of that, the failure of the vibration-sensitive equipment will cause severe economic loss. In order to protect vibration-sensitive equipment or machinery against strong earthquakes, various innovative control algorithms are developed to compensate the internal forces that to be applied. These new or improved control strategies, such as the control algorithms based on optimal control theory and sliding mode control (SMC), are also developed for structures engineering as a key element in smart structure technology. The optimal control theory, one of the most common methodologies in feedback control, finds control forces through achieving a certain optimal criterion by minimizing a cost function. For example, the linear-quadratic regulator (LQR) was the most popular control algorithm over the past three decades, and a number of modifications have been proposed to increase the efficiency of classical LQR algorithm. However, except to the advantage of simplicity and ease of implementation, LQR are susceptible to parameter uncertainty and modeling error due to complex nature of civil structures. Different from LQR control, a robust and easy to be implemented control algorithm, SMC has also been studied. SMC is a nonlinear control methodology that forces the structural system to slide along surfaces or boundaries; hence this control algorithm is naturally robust with respect to parametric uncertainties of a structure. Early attempts at protecting vibration-sensitive equipment were based on the use of existing control algorithms as described above. However, in recent years, researchers have tried to renew the existing control algorithms or developing a new control algorithm to adapt the complex nature of civil structures which include the control of both structures and non

  16. Finite-Time Spacecraft’s Soft Landing on Asteroids Using PD and Nonsingular Terminal Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Keping Liu

    2015-01-01

    Full Text Available This paper presents a continuous control law of probe, which consists of PD (proportional-derivative controller and nonsingular terminal sliding mode controller for probe descending and landing phases, respectively, in the case of the asteroid irregular shape and low gravity. The probe dynamic model is deduced in the landing site coordinate system firstly. Then the reference trajectory based on optimal polynomial in open-loop state is designed, with the suboptimal fuel consumption. Taking into account different characteristics of phases, PD controller and nonsingular terminal sliding mode controller can be employed in the descending phase and the landing phase, respectively, to track the designed reference trajectory. The controller which used the corresponding control methods can meet the motion characteristics and requirements of each stage. Finally simulation experiments are carried out to demonstrate the effectiveness of the proposed method, which can ensure the safe landing of probe and achieve continuous control.

  17. Direct power control of DFIG wind turbine systems based on an intelligent proportional-integral sliding mode control.

    Science.gov (United States)

    Li, Shanzhi; Wang, Haoping; Tian, Yang; Aitouch, Abdel; Klein, John

    2016-09-01

    This paper presents an intelligent proportional-integral sliding mode control (iPISMC) for direct power control of variable speed-constant frequency wind turbine system. This approach deals with optimal power production (in the maximum power point tracking sense) under several disturbance factors such as turbulent wind. This controller is made of two sub-components: (i) an intelligent proportional-integral module for online disturbance compensation and (ii) a sliding mode module for circumventing disturbance estimation errors. This iPISMC method has been tested on FAST/Simulink platform of a 5MW wind turbine system. The obtained results demonstrate that the proposed iPISMC method outperforms the classical PI and intelligent proportional-integral control (iPI) in terms of both active power and response time. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Speed sensoless robust control of permanent magnet synchronous motor based on second-order sliding-mode observer

    Directory of Open Access Journals (Sweden)

    Fezzani Amor

    2014-01-01

    Full Text Available This paper is devoted to the study of the performances of a robust speed sensorless nonlinear control of permanent magnet synchronous machine. In the first part, the controllers are designed using two methods: the first one using the input output feedback linearization control and the second is a nonlinear control based on Lyapunov theory combined with sliding mode control. This second solution shows good robustness with respect to parameter variations, measurement errors and noises. In the second part, the high order sliding mode speed observer is used to overcome the occurring chattering phenomena. The super twisting algorithm is modified in order to design a speed and position observer for PMSM. Finally, simulation results are given to demonstrate the effectiveness and the good performance of the proposed control methods.

  19. ESO-Based Fuzzy Sliding-Mode Control for a 3-DOF Serial-Parallel Hybrid Humanoid Arm

    Directory of Open Access Journals (Sweden)

    Yueling Wang

    2014-01-01

    Full Text Available This paper presents a unique ESO-based fuzzy sliding-mode controller (FSMC-ESO for a 3-DOF serial-parallel hybrid humanoid arm (HHA for the trajectory tracking control problem. The dynamic model of the HHA is obtained by Lagrange method and is nonlinear in dynamics with inertia uncertainty and external disturbance. The FSMC-ESO is based on the combination of the sliding-mode control (SMC, extended state observer (ESO theory, and fuzzy control (FC. The SMC is insensitive to both internal parameter uncertainties and external disturbances. The motivation for using ESO is to estimate the disturbance in real-time. The fuzzy parameter self-tuning strategy is proposed to adjust the switching gain on line according to the running state of the system. The stability of the system is guaranteed in the sense of the Lyapunov stability theorem. The effectiveness and robustness of the designed FSMC-ESO are illustrated by simulations.

  20. A New Optimal Control Algorithm for Quad-rotor Helicopter with State Constraints via Sliding-mode Control

    Directory of Open Access Journals (Sweden)

    Zhao Jing

    2015-01-01

    Full Text Available This paper proposes a strategy of a new optimal sliding-mode control for flight control system with state constraints so that the system guarantees the optimal performance index. Besides, the strategy ensures strong robustness to the internal parametric uncertainty and the external disturbances. In order to have fast transient response speed as well as good tracking accuracy, the integral of the time multiplied by the absolute displacement tracking error is introduced as the performance index. By analyzing the state constraints which are specifically the velocity tracking error constraint and the acceleration tracking error constraint, and the performance index, the parameters of sliding-mode surface and control law are obtained. Finally, the authors conduct the semi physical simulation on Qball-X4 quad-rotor helicopter, showing the effectiveness of the proposed strategy.

  1. Application of second order sliding mode algorithms for output feedback control in hydraulic cylinder drives with profound valve dynamics

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben O.

    2016-01-01

    The application of second order sliding mode algorithms for output feedback control in hydraulic valve-cylinder drives appear attractive due to their simple realization and parametrization, and strong robustness toward bounded parameter variations and uncertainties. However, intrinsic nonlinear...... input signals. The application of some popular second order sliding mode controllers and their smooth counterparts are analyzed and experimentally verified. The controllers are considered for output feedback control and compared with a conventional PI control approach. The controllers under...... consideration are applied for position tracking control of a hydraulic valve-cylinder drive exhibiting strong variations in inertia- and gravitational loads, and furthermore suffer from profound valve dynamics. Results demonstrate that both the twisting- and super twisting algorithms may be successfully applied...

  2. Chaos suppression of Fractional order Willamowski-Rössler Chemical system and its synchronization using Sliding Mode Control

    Science.gov (United States)

    Rajagopal, Karthikeyan; Karthikeyan, Anitha

    2016-09-01

    Most of the Real systems shows chaotic behavior when they approach complex states. Especially in physical and chemical systems these behaviors define the character of the system. The control of these chaotic behaviors is of very high practical importance and hence mathematical models of these chaotic systems proves vital in deciding the control structures. One such model of chemical reactors is the Willamowski-Rössler system (WR). In this paper we derive a fractional order sliding mode control scheme where the states of the WR system are driven back to the defined equilibrium points. We have also synchronized master and slave fractional order WR system using sliding mode control. As the entire control law is defined in fractional order, we derived a new methodology to prove the stability of the controller. The numerical simulation and analysis are achieved with LabVIEW.

  3. Dynamic Sliding Mode Evolution PWM Controller for a Novel High-Gain Interleaved DC-DC Converter in PV System

    Directory of Open Access Journals (Sweden)

    Taizhou Bei

    2014-01-01

    Full Text Available Considering the disadvantages of the traditional high-gain DC-DC converter such as big size, high voltage stress of switches, and large input current ripple, a novel high-gain interleaved boost converter with coupled-inductor and switched-capacitor was proposed correspondingly and the operation principle together with the steady-state analysis of this converter was also described. Besides, a new control approach-dynamic sliding mode evolution PWM controller (DSME PWM for the novel topological converter based on both dynamic evolution and sliding mode control was also presented. From the simulation results and experimental validation the proposed converter can fulfill high-gain boost, low ripple of both the input current and the output voltage. Furthermore, MPPT technique can be also achieved in a short time by simulation. The efficiency and stability of the converter proposed in this paper can be improved.

  4. Comparison of Sliding Mode Control and Fuzzy Logic control applied to Variable Speed Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Souhila Rached Zine

    2015-08-01

    Full Text Available wind energy features prominently as a supplementary energy booster. It does not pollute and is inexhaustible. However, its high cost is a major constraint, especially on the less windy sites. The purpose of wind energy systems is to maximize energy efficiency, and extract maximum power from the wind speed. In This case, the MPPT control becomes important. To realize this control, strategy conventional Proportional and Integral (PI controller is usually used. However, this strategy cannot achieve better performance. This paper proposes other control methods of a turbine which optimizes its production such as fuzzy logic, sliding mode control. These methods improve the quality and energy efficiency. The proposed Sliding Mode Control (SMC strategy and the fuzzy controllers have presented attractive features such as robustness to parametric uncertainties of the turbine, simplicity of its design and good performances. The simulation result under Matlab\\Simulink has validated the performance of the proposed MPPT strategies.

  5. Perancangan Sistem Pengaturan Kestabilan Autonomous Underwater (AUV untuk Gerak Lateral Menggunakan Sliding Mode Control (SMC

    Directory of Open Access Journals (Sweden)

    Septian Ainur Rofiq

    2014-03-01

    Full Text Available Autonomous Underwater Vehicle  (AUV merupakan kendaraan bawah air yang dapat bergerak tanpa kendali manusia dan  bermanuver  sesuai  dengan  perintah  yang  diberikan.  AUV memiliki  kemampuan  manuver  yang  dinamis  untuk  melacak lintasan.  Kemampuan  AUV  mencakup  untuk  beroperasi  di daerah  yang  memiliki  dinamika  nonlinear  dan  belum  dapat diprediksi.  Sehingga  dibutuhkan  model  kontrol  berbasis nonlinear  untuk  meningkatkan  kemampuan  dan  misi  AUV. Gerak lateral merupakan salah satu bentuk pergerakan AUV di dalam  air.  AUV  dijaga  agar  tetap  stabil  pada  lintasan  dan kedalaman  yang  dikehendaki.  Pengaturan  kestabilan  AUV  di dalam air pada gerak lateral menggunakan metode Sliding Mode Control  (SMC  diharapkan  agar  respon  yang  diperoleh menyerupai  input  referensi    sistem  linear  orde  satu  dan  tetap stabil  pada  koordinat  lintasan  yang  telah  ditentukan.  Hasil simulasi  menunjukkan  bahwa  SMC  dapat  mempertahankan kestabilan AUV tetap pada lintasan yang telah ditentukan pada 0 radian dengan osilasi maksimal pada lintasan persegi, segitiga dan jajaran genjang sebesar 0,19 radian atau sekitar 10,89 derajat.

  6. RTDS implementation of an improved sliding mode based inverter controller for PV system.

    Science.gov (United States)

    Islam, Gazi; Muyeen, S M; Al-Durra, Ahmed; Hasanien, Hany M

    2016-05-01

    This paper proposes a novel approach for testing dynamics and control aspects of a large scale photovoltaic (PV) system in real time along with resolving design hindrances of controller parameters using Real Time Digital Simulator (RTDS). In general, the harmonic profile of a fast controller has wide distribution due to the large bandwidth of the controller. The major contribution of this paper is that the proposed control strategy gives an improved voltage harmonic profile and distribute it more around the switching frequency along with fast transient response; filter design, thus, becomes easier. The implementation of a control strategy with high bandwidth in small time steps of Real Time Digital Simulator (RTDS) is not straight forward. This paper shows a good methodology for the practitioners to implement such control scheme in RTDS. As a part of the industrial process, the controller parameters are optimized using particle swarm optimization (PSO) technique to improve the low voltage ride through (LVRT) performance under network disturbance. The response surface methodology (RSM) is well adapted to build analytical models for recovery time (Rt), maximum percentage overshoot (MPOS), settling time (Ts), and steady state error (Ess) of the voltage profile immediate after inverter under disturbance. A systematic approach of controller parameter optimization is detailed. The transient performance of the PSO based optimization method applied to the proposed sliding mode controlled PV inverter is compared with the results from genetic algorithm (GA) based optimization technique. The reported real time implementation challenges and controller optimization procedure are applicable to other control applications in the field of renewable and distributed generation systems. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Sliding-Mode Speed Control of PMSM with Fuzzy-Logic Chattering Minimization—Design and Implementation

    Directory of Open Access Journals (Sweden)

    Fadil Hicham

    2015-07-01

    Full Text Available In this paper a Sliding Mode Control scheme (SMC applied to the Permanent Magnet Synchronous Motor (PMSM speed control is designed and improved. A Fuzzy logic algorithm is added to mitigate chattering caused by discontinuous term in steady states, and to ensure good performances of the controller in transient states. The proposed Fuzzy-SMC performance is tested in simulation and experimental results are obtained using eZdsp F28335.

  8. Sliding mode control of an autonomous parallel fuel cell-super capacitor power source

    Energy Technology Data Exchange (ETDEWEB)

    More, Jeronimo J. [Universidad Nacional de La Plata (UNLP), La Plata, Buenos Aires (Argentina). Facultad de Ingenieria. Lab. de Electronica Industrial, Control e Instrumentacion], Email: jmore@ing.unlp.edu.ar; Puleston, Paul F. [Consejo de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Kunusch, Cristian; Colomer, Jordi Riera I. [Universitat Politecnica de Catalunya, Barcelona (Spain). Inst. de Robotica i Informatica Industrial (IRII)

    2010-07-01

    Nowadays, hydrogen fuel cell (FC) based systems emerge as one promising renewable alternative to fossil fuel systems in automotive and residential applications. However, their output dynamic response is relatively slow, mostly due to water and reactant gases dynamics. To overcome this limitation, FC-super capacitors (SCs) topologies can be used. The latter is capable of managing very fast power variations, presenting in addition high power density, long life cycle and good charge/discharge efficiency. In this work, a FC-SCs-based autonomous hybrid system for residential applications is considered. The FC and SCs are connected in parallel, through two separate DC/DC converters, to a DC bus. Under steady state conditions, the FC must deliver the load power requirement, while maintaining the SCs voltage regulated to the desired value. Under sudden load variations, the FC current rate must be limited to assure a safe transition to the new point of operation. During this current rate limitation mode, the SCs must deliver or absorb the power difference. To this end, a sliding mode strategy is proposed to satisfy to control objectives. The main one is the robust regulation of the DC bus voltage, even in the presence of system uncertainties and disturbances, such as load changes and FC voltage variations. Additionally, a second control objective is attained, namely to guarantee the adequate level of charge in the SCs, once the FC reaches the new steady state operation point. In this way, the system can meet the load power demand, even under sudden changes, and it can also satisfy a power demand higher than the nominal FC power, during short periods. The proposed control strategy is evaluated exhaustively by computer simulation considering fast load variations. The results presented in this work, corresponds to the first stage of a R and D collaboration project for the design and development of a novel FC-SCs-based autonomous hybrid system. In the next phase, the proposed

  9. Leader-follower formation control of underactuated surface vehicles based on sliding mode control and parameter estimation.

    Science.gov (United States)

    Sun, Zhijian; Zhang, Guoqing; Lu, Yu; Zhang, Weidong

    2017-12-05

    This paper studies the leader-follower formation control of underactuated surface vehicles with model uncertainties and environmental disturbances. A parameter estimation and upper bound estimation based sliding mode control scheme is proposed to solve the problem of the unknown plant parameters and environmental disturbances. For each of these leader-follower formation systems, the dynamic equations of position and attitude are analyzed using coordinate transformation with the aid of the backstepping technique. All the variables are guaranteed to be uniformly ultimately bounded stable in the closed-loop system, which is proven by the distribution design Lyapunov function synthesis. The main advantages of this approach are that: first, parameter estimation based sliding mode control can enhance the robustness of the closed-loop system in presence of model uncertainties and environmental disturbances; second, a continuous function is developed to replace the signum function in the design of sliding mode scheme, which devotes to reduce the chattering of the control system. Finally, numerical simulations are given to demonstrate the effectiveness of the proposed method. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Parameters Designing of Slide Mode Variable Structure Controller of Bus Voltage of DC Microgrid Based on Proportion Switching Function

    Directory of Open Access Journals (Sweden)

    Sun Zhenchuan

    2017-01-01

    Full Text Available Constant value control of the DC-bus voltage is a essential problem of the control system of the DC microgrids. DC-DC converters are applied in parallel to realize the transform of energy from the distributed generations (DGs to the DC-bus. Droop control methods are applied to the DC-bus voltage while PI controllers are used in controlling the duty ratios of the converters. This method may bring out the slow response speed of the system accompanied by the large ripple of the voltage. The slide mode variable structure control can speed up the response and reduce the ripple of the voltage as well. In the traditional slide mode control based on the proportion switching function, the denominator of the transfer function of the controlled plant is a second-order characteristic polynomial without the constant term. The denominators of the transfer functions of the buck DC-DC converters contain the constant terms. The designing of the parameters of the slide mode control based on the proportion switching function is analyzed based on mathematics deductions. Simulation results show that the selected parameters can not only speed up the response of the system but also greatly reduce the ripple of the voltage.

  11. Toward Modular Soft Robotics: Proprioceptive Curvature Sensing and Sliding-Mode Control of Soft Bidirectional Bending Modules.

    Science.gov (United States)

    Luo, Ming; Skorina, Erik H; Tao, Weijia; Chen, Fuchen; Ozel, Selim; Sun, Yinan; Onal, Cagdas D

    2017-06-01

    Real-world environments are complex, unstructured, and often fragile. Soft robotics offers a solution for robots to safely interact with the environment and human coworkers, but suffers from a host of challenges in sensing and control of continuously deformable bodies. To overcome these challenges, this article considers a modular soft robotic architecture that offers proprioceptive sensing of pressure-operated bending actuation modules. We present integrated custom magnetic curvature sensors embedded in the neutral axis of bidirectional bending actuators. We describe our recent advances in the design and fabrication of these modules to improve the reliability of proprioceptive curvature feedback over our prior work. In particular, we study the effect of dimensional parameters on improving the linearity of curvature measurements. In addition, we present a sliding-mode controller formulation that drives the binary solenoid valve states directly, giving the control system the ability to hold the actuator steady without continuous pressurization and depressurization. In comparison to other methods, this control approach does not rely on pulse width modulation and hence offers superior dynamic performance (i.e., faster response rates). Our experimental results indicate that the proposed soft robotic modules offer a large range of bending angles with monotonic and more linear embedded curvature measurements, and that the direct sliding-mode control system exhibits improved bandwidth and a notable reduction in binary valve actuation operations compared to our earlier iterative sliding-mode controller.

  12. Construction of AN Active Suspension System of a Quarter CAR Model Using the Concept of Sliding Mode Control

    Science.gov (United States)

    YOSHIMURA, T.; KUME, A.; KURIMOTO, M.; HINO, J.

    2001-01-01

    This paper is concerned with the construction of an active suspension system for a quarter car model using the concept of sliding mode control. The active control is derived by the equivalent control and switching function where the sliding surface is obtained by using Linear quadratic control (LQ control) theory. The active control is generated with non-negligible time lag by using a pneumatic actuator, and the road profile is estimated by using the minimum order observer based on a linear system transformed from the exact non-linear system. The experimental result indicates that the proposed active suspension system is more effective in the vibration isolation of the car body than the linear active suspension system based on LQ control theory and the passive suspension system.

  13. Robust motion control of oscillatory-base manipulators h∞-control and sliding-mode-control-based approaches

    CERN Document Server

    Toda, Masayoshi

    2016-01-01

    This book provides readers with alternative robust approaches to control design for an important class of systems characteristically associated with ocean-going vessels and structures. These systems, which include crane vessels, on-board cranes, radar gimbals, and a conductivity temperature and depth winch, are modelled as manipulators with oscillating bases. One design approach is based on the H-infinity control framework exploiting an effective combination of PD control, an extended matrix polytope and a robust stability analysis method with a state-dependent coefficient form. The other is based on sliding-mode control using some novel nonlinear sliding surfaces. The model demonstrates how successful motion control can be achieved by suppressing base oscillations and in the presence of uncertainties. This is important not only for ocean engineering systems in which the problems addressed here originate but more generally as a benchmark platform for robust motion control with disturbance rejection. Researche...

  14. Unwinding forward and sliding back: an intermittent unwinding mode of the BLM helicase.

    Science.gov (United States)

    Wang, Shuang; Qin, Wei; Li, Jing-Hua; Lu, Ying; Lu, Ke-Yu; Nong, Da-Guan; Dou, Shuo-Xing; Xu, Chun-Hua; Xi, Xu-Guang; Li, Ming

    2015-04-20

    There are lines of evidence that the Bloom syndrome helicase, BLM, catalyzes regression of stalled replication forks and disrupts displacement loops (D-loops) formed during homologous recombination (HR). Here we constructed a forked DNA with a 3' single-stranded gap and a 5' double-stranded handle to partly mimic a stalled DNA fork and used magnetic tweezers to study BLM-catalyzed unwinding of the forked DNA. We have directly observed that the BLM helicase may slide on the opposite strand for some distance after duplex unwinding at different forces. For DNA construct with a long hairpin, progressive unwinding of the hairpin is frequently interrupted by strand switching and backward sliding of the enzyme. Quantitative study of the uninterrupted unwinding length (time) has revealed a two-state-transition mechanism for strand-switching during the unwinding process. Mutational studies revealed that the RQC domain plays an important role in stabilizing the helicase/DNA interaction during both DNA unwinding and backward sliding of BLM. Especially, Lys1125 in the RQC domain, a highly conserved amino acid among RecQ helicases, may be involved in the backward sliding activity. We have also directly observed the in vitro pathway that BLM disrupts the mimic stalled replication fork. These results may shed new light on the mechanisms for BLM in DNA repair and homologous recombination. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. Slide 1

    Indian Academy of Sciences (India)

    Slide 25 · Life course epidemiology and chronic diseases · Models · Slide 28 · Slide 29 · Slide 30 · New Delhi Birth Cohort · New Delhi Birth Cohort (NDBC) · Slide 33 · Slide 34 · Slide 35 · Slide 36 · Slide 37 · Slide 38 · Slide 39 · CONCLUSIONS Urban Children and Adolescents · CONCLUSIONS New Delhi Birth Cohort.

  16. SU-F-J-10: Sliding Mode Control of a SMA Actuated Active Flexible Needle for Medical Procedures

    Energy Technology Data Exchange (ETDEWEB)

    Podder, T [University Hospitals Case Medical Center, Cleveland, OH (United States)

    2016-06-15

    Purpose: In medical interventional procedures such as brachytherapy, ablative therapies and biopsy precise steering and accurate placement of needles are very important for anatomical obstacle avoidance and accurate targeting. This study presents the efficacy of a sliding mode controller for Shape Memory Alloy (SMA) actuated flexible needle for medical procedures. Methods: Second order system dynamics of the SMA actuated active flexible needle was used for deriving the sliding mode control equations. Both proportional-integral-derivative (PID) and adaptive PID sliding mode control (APIDSMC) algorithms were developed and implemented. The flexible needle was attached at the end of a 6 DOF robotic system. Through LabView programming environment, the control commands were generated using the PID and APIDSMC algorithms. Experiments with artificial tissue mimicking phantom were performed to evaluate the performance of the controller. The actual needle tip position was obtained using an electromagnetic (EM) tracking sensor (Aurora, NDI, waterloo, Canada) at a sampling period of 1ms. During experiment, external disturbances were created applying force and thermal shock to investigate the robustness of the controllers. Results: The root mean square error (RMSE) values for APIDSMC and PID controllers were 0.75 mm and 0.92 mm, respectively, for sinusoidal reference input. In the presence of external disturbances, the APIDSMC controller showed much smoother and less overshooting response compared to that of the PID controller. Conclusion: Performance of the APIDSMC was superior to the PID controller. The APIDSMC was proved to be more effective controller in compensating the SMA uncertainties and external disturbances with clinically acceptable thresholds.

  17. Maximum power point tracking algorithm based on sliding mode and fuzzy logic for photovoltaic sources under variable environmental conditions

    Science.gov (United States)

    Atik, L.; Petit, P.; Sawicki, J. P.; Ternifi, Z. T.; Bachir, G.; Della, M.; Aillerie, M.

    2017-02-01

    Solar panels have a nonlinear voltage-current characteristic, with a distinct maximum power point (MPP), which depends on the environmental factors, such as temperature and irradiation. In order to continuously harvest maximum power from the solar panels, they have to operate at their MPP despite the inevitable changes in the environment. Various methods for maximum power point tracking (MPPT) were developed and finally implemented in solar power electronic controllers to increase the efficiency in the electricity production originate from renewables. In this paper we compare using Matlab tools Simulink, two different MPP tracking methods, which are, fuzzy logic control (FL) and sliding mode control (SMC), considering their efficiency in solar energy production.

  18. Design of Nonlinear Robust Rotor Current Controller for DFIG Based on Terminal Sliding Mode Control and Extended State Observer

    Directory of Open Access Journals (Sweden)

    Guowei Cai

    2014-01-01

    Full Text Available As to strong nonlinearity of doubly fed induction generators (DFIG and uncertainty of its model, a novel rotor current controller with nonlinearity and robustness is proposed to enhance fault ride-though (FRT capacities of grid-connected DFIG. Firstly, the model error, external disturbances, and the uncertain factors were estimated by constructing extended state observer (ESO so as to achieve linearization model, which is compensated dynamically from nonlinear model. And then rotor current controller of DFIG is designed by using terminal sliding mode variable structure control theory (TSMC. The controller has superior dynamic performance and strong robustness. The simulation results show that the proposed control approach is effective.

  19. Real-time crankshaft angular speed tracking and indicated torque estimation via optimized Luenberger sliding mode observer

    Science.gov (United States)

    Zhang, Y.; Tan, R.; Zheng, T. X.; Zhou, T. L.; Han, W. M.; Wang, Y. J.

    2017-03-01

    The interest in engine indicated torque estimation plays an important role in the automotive industry. In this study, an optimized Luenberger sliding mode observer is proposed based on easily available crankshaft angular speed of a four-cylinder spark ignition (SI) engine. Especially, the new observer is applied to track crankshaft angular speed and estimate engine indicated torque in New European Drive Cycle (NEDC). Convergence is proven through Lyapunov stability theory. The experimental results show that the proposed estimated technique can effectively track speed and has a higher accuracy in steady state.

  20. Forecasting stochastic neural network based on financial empirical mode decomposition.

    Science.gov (United States)

    Wang, Jie; Wang, Jun

    2017-06-01

    In an attempt to improve the forecasting accuracy of stock price fluctuations, a new one-step-ahead model is developed in this paper which combines empirical mode decomposition (EMD) with stochastic time strength neural network (STNN). The EMD is a processing technique introduced to extract all the oscillatory modes embedded in a series, and the STNN model is established for considering the weight of occurrence time of the historical data. The linear regression performs the predictive availability of the proposed model, and the effectiveness of EMD-STNN is revealed clearly through comparing the predicted results with the traditional models. Moreover, a new evaluated method (q-order multiscale complexity invariant distance) is applied to measure the predicted results of real stock index series, and the empirical results show that the proposed model indeed displays a good performance in forecasting stock market fluctuations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Adaptive Fuzzy Sliding Mode Control for the Probe Soft Landing on the Asteroids with Weak Gravitational Field

    Directory of Open Access Journals (Sweden)

    Yuanchun Li

    2015-01-01

    Full Text Available For the trajectory control of the probe soft landing on the asteroids with weak gravitational field, this paper presents a combined integral sliding mode control with an adaptive fuzzy logic system, named adaptive fuzzy sliding mode control (AFSMC scheme. Considering the uncertainty of the orbit dynamics model in the small body fixed coordinate system, and the polyhedron modeling uncertainty in the gravitational potential, a fuzzy logic system is adopted to approximate the upper bound of the uncertainties. In addition, a robust control item is introduced to compensate for the approximation error of fuzzy logic system. The designed adaptive law and robust item make the closed-loop control stable and the tracking errors are convergent to zero. The controller not only guarantees the rapidity and accuracy of the desired trajectory tracking, but also enhances the robustness of the control system, improving the dynamic tracking performance for the probe soft landing on asteroids. Finally, the contrastive simulation results are presented to show the feasibility and effectiveness of the proposed control scheme.

  2. Finite-time sliding mode attitude control for a reentry vehicle with blended aerodynamic surfaces and a reaction control system

    Directory of Open Access Journals (Sweden)

    Geng Jie

    2014-08-01

    Full Text Available This paper proposes a finite-time robust flight controller, targeting for a reentry vehicle with blended aerodynamic surfaces and a reaction control system (RCS. Firstly, a novel finite-time attitude controller is pointed out with the introduction of a nonsingular finite-time sliding mode manifold. The attitude tracking errors are mathematically proved to converge to zero within finite time which can be estimated. In order to improve the performance, a second-order finite-time sliding mode controller is further developed to effectively alleviate chattering without any deterioration of robustness and accuracy. Moreover, an optimization control allocation algorithm, using linear programming and a pulse-width pulse-frequency (PWPF modulator, is designed to allocate torque commands for all the aerodynamic surface deflections and on–off switching-states of RCS thrusters. Simulations are provided for the reentry vehicle considering uncertain parameters and external disturbances for practical purposes, and the results demonstrate the effectiveness and robustness of the attitude control system.

  3. Robust fractional order sliding mode control of doubly-fed induction generator (DFIG)-based wind turbines.

    Science.gov (United States)

    Ebrahimkhani, Sadegh

    2016-07-01

    Wind power plants have nonlinear dynamics and contain many uncertainties such as unknown nonlinear disturbances and parameter uncertainties. Thus, it is a difficult task to design a robust reliable controller for this system. This paper proposes a novel robust fractional-order sliding mode (FOSM) controller for maximum power point tracking (MPPT) control of doubly fed induction generator (DFIG)-based wind energy conversion system. In order to enhance the robustness of the control system, uncertainties and disturbances are estimated using a fractional order uncertainty estimator. In the proposed method a continuous control strategy is developed to achieve the chattering free fractional order sliding-mode control, and also no knowledge of the uncertainties and disturbances or their bound is assumed. The boundedness and convergence properties of the closed-loop signals are proven using Lyapunov׳s stability theory. Simulation results in the presence of various uncertainties were carried out to evaluate the effectiveness and robustness of the proposed control scheme. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Output Feedback Finite-Time Stabilization of Systems Subject to Hölder Disturbances via Continuous Fractional Sliding Modes

    Directory of Open Access Journals (Sweden)

    Aldo-Jonathan Muñoz-Vázquez

    2017-01-01

    Full Text Available The problem of designing a continuous control to guarantee finite-time tracking based on output feedback for a system subject to a Hölder disturbance has remained elusive. The main difficulty stems from the fact that such disturbance stands for a function that is continuous but not necessarily differentiable in any integer-order sense, yet it is fractional-order differentiable. This problem imposes a formidable challenge of practical interest in engineering because (i it is common that only partial access to the state is available and, then, output feedback is needed; (ii such disturbances are present in more realistic applications, suggesting a fractional-order controller; and (iii continuous robust control is a must in several control applications. Consequently, these stringent requirements demand a sound mathematical framework for designing a solution to this control problem. To estimate the full state in finite-time, a high-order sliding mode-based differentiator is considered. Then, a continuous fractional differintegral sliding mode is proposed to reject Hölder disturbances, as well as for uncertainties and unmodeled dynamics. Finally, a homogeneous closed-loop system is enforced by means of a continuous nominal control, assuring finite-time convergence. Numerical simulations are presented to show the reliability of the proposed method.

  5. A novel approach for state of charge estimation based on adaptive switching gain sliding mode observer in electric vehicles

    Science.gov (United States)

    Chen, Xiaopeng; Shen, Weixiang; Cao, Zhenwei; Kapoor, Ajay

    2014-01-01

    In this paper, a novel approach for battery state of charge (SOC) estimation in electric vehicles (EVs) based on an adaptive switching gain sliding mode observer (ASGSMO) has been presented. To design the ASGSMO for the SOC estimation, the state equations based on a battery equivalent circuit model (BECM) are derived to represent dynamic behaviours of a battery. Comparing with a conventional sliding mode observer, the ASGSMO has a capability of minimising chattering levels in the SOC estimation by using the self-adjusted switching gain while maintaining the characteristics of being able to compensate modelling errors caused by the parameter variations of the BECM. Lyapunov stability theory is adopted to prove the error convergence of the ASGSMO for the SOC estimation. The lithium-polymer battery (LiPB) is utilised to conduct experiments for determining the parameters of the BECM and verifying the effectiveness of the proposed ASGSMO in various discharge current profiles including EV driving conditions in both city and suburban.

  6. Integral Plus Resonant Sliding Mode Direct Power Control for VSC-HVDC Systems under Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Weipeng Yang

    2017-10-01

    Full Text Available An integral plus resonant sliding mode direct power control (IRSMC DPC strategy for voltage source converter high voltage direct current (VSC-HVDC systems under unbalanced grid voltage conditions is proposed in this paper. Through detailed instantaneous power flow analysis, a generalized power compensation method, by which the ratio between the amplitude of active and reactive power ripples can be controlled continuously, is obtained. This enables the system to provide flexible power control, so that the desired performance of the system on both the ac and dc sides can be attained under different operating conditions. When the grid voltage is unbalanced, one or both of the active and reactive power terms contain ripples, oscillating at twice the grid frequency, to obtain non-distorted ac current. A power controller consisting of the proportional, integral and resonant control laws is designed using the sliding mode control approach, to achieve accurate power control objective. Simulation studies on a two-terminal VSC-HVDC system using MATLAB/SIMULINK (R2013b, Mathworks, Natick, MA, USA are conducted to verify the effectiveness of the IRSMC DPC strategy. The results show that this strategy ensures satisfactory performance of the system over a wide range of operating conditions.

  7. A new adjustable gains for second order sliding mode control of saturated DFIG-based wind turbine

    Science.gov (United States)

    Bounadja, E.; Djahbar, A.; Taleb, R.; Boudjema, Z.

    2017-02-01

    The control of Doubly-Fed induction generator (DFIG), used in wind energy conversion, has been given a great deal of interest. Frequently, this control has been dealt with ignoring the magnetic saturation effect in the DFIG model. The aim of the present work is twofold: firstly, the magnetic saturation effect is accounted in the control design model; secondly, a new second order sliding mode control scheme using adjustable-gains (AG-SOSMC) is proposed to control the DFIG via its rotor side converter. This scheme allows the independent control of the generated active and reactive power. Conventionally, the second order sliding mode control (SOSMC) applied to the DFIG, utilize the super-twisting algorithm with fixed gains. In the proposed AG-SOSMC, a simple means by which the controller can adjust its behavior is used. For that, a linear function is used to represent the variation in gain as a function of the absolute value of the discrepancy between the reference rotor current and its measured value. The transient DFIG speed response using the aforementioned characteristic is compared with the one determined by using the conventional SOSMC controller with fixed gains. Simulation results show, accurate dynamic performances, quicker transient response and more accurate control are achieved for different operating conditions.

  8. Free-flying dynamics and control of an astronaut assistant robot based on fuzzy sliding mode algorithm

    Science.gov (United States)

    Gao, Qing; Liu, Jinguo; Tian, Tongtong; Li, Yangmin

    2017-09-01

    Space robots can perform some tasks in harsh environment as assistants of astronauts or substitutions of astronauts. Taking the limited working time and the arduous task of the astronauts in the space station into account, an astronaut assistant robot (AAR-2) applied in the space station is proposed and designed in this paper. The AAR-2 is achieved with some improvements on the basis of AAR-1 which was designed before. It can exploit its position and attitude sensors and control system to free flight or hover in the space cabin. And it also has a definite environmental awareness and artificial intelligence to complete some specified tasks under the control of astronauts or autonomously. In this paper, it mainly analyzes and controls the 6-DOF motion of the AAR-2. Firstly, the system configuration of AAR-2 is specifically described, and the movement principles are analyzed. Secondly, according to the physical model of the AAR-2, the Newton - Euler equation is applied in the preparation of space dynamics model of 6-DOF motion. Then, according to the mathematical model's characteristics which are nonlinear and strong coupling, a dual closed loop position and attitude controller based on fuzzy sliding mode control is proposed and designed. Finally, simulation experiments are appropriate to provide for AAR-2 control system by using Matlab/Simulink. From the simulation results it can be observed that the designed fuzzy sliding mode controller can control the 6-DOF motion of AAR-2 quickly and precisely.

  9. Observer-based adaptive sliding mode backstepping output-feedback DSC for spin-stabilized canard-controlled projectiles

    Directory of Open Access Journals (Sweden)

    Yuanchuan SHEN

    2017-06-01

    Full Text Available This article presents a complete nonlinear controller design for a class of spin-stabilized canard-controlled projectiles. Uniformly ultimate boundedness and tracking are achieved, exploiting a heavily coupled, bounded uncertain and highly nonlinear model of longitudinal and lateral dynamics. In order to estimate unmeasurable states, an observer is proposed for an augmented multiple-input-multiple-output (MIMO nonlinear system with an adaptive sliding mode term against the disturbances. Under the frame of a backstepping design, an adaptive sliding mode output-feedback dynamic surface control (DSC approach is derived recursively by virtue of the estimated states. The DSC technique is adopted to overcome the problem of “explosion of complexity” and relieve the stress of the guidance loop. It is proven that all signals of the MIMO closed-loop system, including the observer and controller, are uniformly ultimately bounded, and the tracking errors converge to an arbitrarily small neighborhood of the origin. Simulation results for the observer and controller are provided to illustrate the feasibility and effectiveness of the proposed approach.

  10. Research of Active Power Filter Modeling with Grid Impedance in Feedback Linearization and Quasi-Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Zeyu Shi

    2017-01-01

    Full Text Available Active power filter (APF is the most popular device in regulating power quality issues. Currently, most literatures ignored the impact of grid impedance and assumed the load voltage is ideal, which had not described the system accurately. In addition, the controllers applied PI control; thus it is hard to improve the compensation quality. This paper establishes a precise model which consists of APF, load, and grid impedance. The Bode diagram of traditional simplified model is obviously different with complete model, which means the descriptions of the system based on the traditional simplified model are inaccurate and incomplete. And then design exact feedback linearization and quasi-sliding mode control (FBL-QSMC is based on precise model in inner current loop. The system performances in different parameters are analyzed and dynamic performance of proposed algorithm is compared with traditional PI control algorithm. At last, simulations are taken in three cases to verify the performance of proposed control algorithm. The results proved that the proposed feedback linearization and quasi-sliding mode control algorithm has fast response and robustness; the compensation performance is superior to PI control obviously, which also means the complete modeling and proposed control algorithm are correct.

  11. Implementation of a sliding-mode-based position sensorless drive for high-speed micro permanent-magnet synchronous motors.

    Science.gov (United States)

    Chi, Wen-Chun; Cheng, Ming-Yang

    2014-03-01

    Due to issues such as limited space, it is difficult if it is not impossible to employ a position sensor in the drive control of high-speed micro PMSMs. In order to alleviate this problem, this paper analyzes and implements a simple and robust position sensorless field-oriented control method of high-speed micro PMSMs based on the sliding-mode observer. In particular, the angular position and velocity of the rotor of the high-speed micro PMSM are estimated using the sliding-mode observer. This observer is able to accurately estimate rotor position in the low speed region and guarantee fast convergence of the observer in the high speed region. The proposed position sensorless control method is suitable for electric dental handpiece motor drives where a wide speed range operation is essential. The proposed sensorless FOC method is implemented using a cost-effective 16-bit microcontroller and tested in a prototype electric dental handpiece motor. Several experiments are performed to verify the effectiveness of the proposed method. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  12. A novel discrete adaptive sliding-mode-like control method for ionic polymer-metal composite manipulators

    Science.gov (United States)

    Sun, Zhiyong; Hao, Lina; Chen, Wenlin; Li, Zhi; Liu, Liqun

    2013-09-01

    Ionic polymer-metal composite (IPMC), also called artificial muscle, is an EAP material which can generate a relatively large deformation with a low driving voltage (generally less than 5 V). Like other EAP materials, IPMC possesses strong nonlinear properties, which can be described as a hybrid of back-relaxation (BR) and hysteresis characteristics, which also vary with water content, environmental temperature and even the usage consumption. Nowadays, many control approaches have been developed to tune the IPMC actuators, among which adaptive methods show a particular striking performance. To deal with IPMCs’ nonlinear problem, this paper represents a robust discrete adaptive inverse (AI) control approach, which employs an on-line identification technique based on the BR operator and Prandtl-Ishlinskii (PI) hysteresis operator hybrid model estimation method. Here the newly formed control approach is called discrete adaptive sliding-mode-like control (DASMLC) due to the similarity of its design method to that of a sliding mode controller. The weighted least mean squares (WLMS) identification method was employed to estimate the hybrid IPMC model because of its advantage of insensitivity to environmental noise. Experiments with the DASMLC approach and a conventional PID controller were carried out to compare and demonstrate the proposed controller’s better performance.

  13. A Real-Time Sliding Mode Control for a Wind Energy System Based on a Doubly Fed Induction Generator

    Directory of Open Access Journals (Sweden)

    Oscar Barambones

    2014-10-01

    Full Text Available In this paper, a real time sliding mode control scheme for a variable speed wind turbine that incorporates a doubly feed induction generator is described. In this design, the so-called vector control theory is applied, in order to simplify the system electrical equations. The proposed control scheme involves a low computational cost and therefore can be implemented in real-time applications using a low cost Digital Signal Processor (DSP. The stability analysis of the proposed sliding mode controller under disturbances and parameter uncertainties is provided using the Lyapunov stability theory. A new experimental platform has been designed and constructed in order to analyze the real-time performance of the proposed controller in a real system. Finally, the experimental validation carried out in the experimental platform shows; on the one hand that the proposed controller provides high-performance dynamic characteristics, and on the other hand that this scheme is robust with respect to the uncertainties that usually appear in the real systems.

  14. Deep convolutional neural networks for automatic classification of gastric carcinoma using whole slide images in digital histopathology.

    Science.gov (United States)

    Sharma, Harshita; Zerbe, Norman; Klempert, Iris; Hellwich, Olaf; Hufnagl, Peter

    2017-06-16

    Deep learning using convolutional neural networks is an actively emerging field in histological image analysis. This study explores deep learning methods for computer-aided classification in H&E stained histopathological whole slide images of gastric carcinoma. An introductory convolutional neural network architecture is proposed for two computerized applications, namely, cancer classification based on immunohistochemical response and necrosis detection based on the existence of tumor necrosis in the tissue. Classification performance of the developed deep learning approach is quantitatively compared with traditional image analysis methods in digital histopathology requiring prior computation of handcrafted features, such as statistical measures using gray level co-occurrence matrix, Gabor filter-bank responses, LBP histograms, gray histograms, HSV histograms and RGB histograms, followed by random forest machine learning. Additionally, the widely known AlexNet deep convolutional framework is comparatively analyzed for the corresponding classification problems. The proposed convolutional neural network architecture reports favorable results, with an overall classification accuracy of 0.6990 for cancer classification and 0.8144 for necrosis detection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Context-aware stacked convolutional neural networks for classification of breast carcinomas in whole-slide histopathology images.

    Science.gov (United States)

    Bejnordi, Babak Ehteshami; Zuidhof, Guido; Balkenhol, Maschenka; Hermsen, Meyke; Bult, Peter; van Ginneken, Bram; Karssemeijer, Nico; Litjens, Geert; van der Laak, Jeroen

    2017-10-01

    Currently, histopathological tissue examination by a pathologist represents the gold standard for breast lesion diagnostics. Automated classification of histopathological whole-slide images (WSIs) is challenging owing to the wide range of appearances of benign lesions and the visual similarity of ductal carcinoma in-situ (DCIS) to invasive lesions at the cellular level. Consequently, analysis of tissue at high resolutions with a large contextual area is necessary. We present context-aware stacked convolutional neural networks (CNN) for classification of breast WSIs into normal/benign, DCIS, and invasive ductal carcinoma (IDC). We first train a CNN using high pixel resolution to capture cellular level information. The feature responses generated by this model are then fed as input to a second CNN, stacked on top of the first. Training of this stacked architecture with large input patches enables learning of fine-grained (cellular) details and global tissue structures. Our system is trained and evaluated on a dataset containing 221 WSIs of hematoxylin and eosin stained breast tissue specimens. The system achieves an AUC of 0.962 for the binary classification of nonmalignant and malignant slides and obtains a three-class accuracy of 81.3% for classification of WSIs into normal/benign, DCIS, and IDC, demonstrating its potential for routine diagnostics.

  16. Motion performance analysis and control mode design for the cross slide

    Science.gov (United States)

    Xie, Dong; Zhu, Jianqu; Wang, Min; Li, Zhengzhong; Wang, Feng

    2017-09-01

    The motion control system which is constructed by using the programmable controller and the motion controller has been widely applied to various mechanical systems. This paper takes a cross slide as an example, the motion control system is composed of the GE FANUC PAC and DSM324i, and the movement performance simulation model is established. The motion performance by linear acceleration and deceleration algorithm in the case of two axis synchronous movement is analyzed. The relation between the displacement command and the parameters of the acceleration and the velocity is derivated, and the trajectory curve of movement performance under a variety of instruction is gained. The control instruction meet the linear motion is designed by the model.

  17. Reaction rate reconstruction from biomass concentration measurement in bioreactors using modified second-order sliding mode algorithms.

    Science.gov (United States)

    De Battista, Hernán; Picó, Jesús; Garelli, Fabricio; Navarro, José Luis

    2012-11-01

    This paper deals with the estimation of unknown signals in bioreactors using sliding observers. Particular attention is drawn to estimate the specific growth rate of microorganisms from measurement of biomass concentration. In a recent article, notions of high-order sliding modes have been used to derive a growth rate observer for batch processes. In this paper we generalize and refine these preliminary results. We develop a new observer with a different error structure to cope with other types of processes. Furthermore, we show that these observers are equivalent, under coordinate transformations and time scaling, to the classical super-twisting differentiator algorithm, thus inheriting all its distinctive features. The new observers' family achieves convergence to time-varying unknown signals in finite time, and presents the best attainable estimation error order in the presence of noise. In addition, the observers are robust to modeling and parameter uncertainties since they are based on minimal assumptions on bioprocess dynamics. In addition, they have interesting applications in fault detection and monitoring. The observers performance in batch, fed-batch and continuous bioreactors is assessed by experimental data obtained from the fermentation of Saccharomyces Cerevisiae on glucose.

  18. Rotor Current Control of DFIG for Improving Fault Ride - Through Using a Novel Sliding Mode Control Approach

    Science.gov (United States)

    Cai, Guowei; Liu, Cheng; Yang, Deyou

    2013-11-01

    The doubly fed induction generators (DFIG) have been recognized as the dominant technology used in wind power generation systems with the rapid development of wind power. However, continuous operation of DFIG may cause a serious wind turbine generators tripping accident, due to destructive over-current in the rotor winding which is caused by the power system fault or inefficient fault ride-through (FRT) strategy. A new rotor current control scheme in the rotor-side converter (RSC) ispresented to enhance FRT capacities of grid-connected DFIG. Due to the strongly nonlinear nature of DFIG and insensitive to DFIG parameter's variations, a novel sliding mode controller was designed. The controller combines extended state observer (ESO) with sliding model variable structure control theory. The simulation is carried out to verify the effectiveness of the proposed control approach under various types of grid disturbances. It is shown that the proposed controller provides enhanced transient features than the classic proportional-integral control. The proposed control method can effectively reduce over-current in the RSC, and the transient pulse value of electromagnetic torque is too large under power grid fault.

  19. Discrete-Time Integral Sliding Mode Control with Disturbances Compensation and Reduced Chattering for Pv Grid-Connected Inverter

    Science.gov (United States)

    Meo, Santolo; Sorrentino, Vincenzo

    2015-03-01

    In the paper a new discrete-time integral sliding mode control (DISMC) with disturbances compensation and reduced chattering for grid-connected inverter is proposed for active and reactive power regulation. Differently by many SMC proposed in literature that have a time-continuous formulation in spite have been implemented with digital processor, the proposed DISMC is fully formulated in discrete-time, taking into account the effects introduced by a microprocessor-based implementation. As will be demonstrated such approach consents to reduce the chattering about the sliding manifold within a boundary layer of O(T2) thickness instead of O(T) (being T the sampling period of the control algorithm). Moreover it introduces a correction of the control vector which eliminates the influence of modeling error and external disturbances improving stability and robustness of the controlled system. Constant converter switching frequency is achieved by using space vector modulation, which eases the design of the ac harmonic filter. In the paper, after a detailed formalization of the proposed control algorithm, several numerical and experimental results on a three-phase grid-connected inverter prototype are shown, proving the effectiveness of the control strategy.

  20. Perancangan dan Implementasi Pengaturan Kecepatan Motor Tiga Fasa Pada Mesin Sentrifugal Menggunakan Metode Sliding Mode Control (SMC

    Directory of Open Access Journals (Sweden)

    Adityo Yudistira

    2014-03-01

    Full Text Available Motor induksi tiga fasa banyak digunakan di industri, salah satunya pada industri pabrik gula. Di industri pabrik gula motor industri tiga fasa banyak digunakan pada mesin sentrifugal. Mesin ini digunakan pada proses pemisahan cairan massacuite dan strup hingga didapat kristal gula. Pada proses tersebut terjadi perubahan beban oleh karena itu pada siklus kecepatannya mengalami proses Charging, Spinning dan Discharging. Pengaturan kecepatan motor induksi masih dilakukan secara manual yaitu dengan merubah posisi puli atau ukuran poros dari mesin sentrifugal. Pengaturan dengan metode ini mengakibatkan kecepatan motor akan sulit dikendalikan sesuai dengan yang diharapkan. Pengaturan kecepatan yang tidak tepat juga dapat mengakibatkan hasil produksi gula yang kurang maksimal. Oleh karena itu dibutuhkan metode kontrol untuk mengoptimalkan kecepatan setpoint motor saat mengalami proses Charging, Spinning dan Discharging. Metode kontrol yang digunakan adalah metode Sliding Mode Control. Kontroler SMC yang diimplementasikan pada PLC memiliki W= 10 dan α=0,2. Dari hasil analisa sliding surface diketahui bahwa semakin bertambahnya beban maka hitting time semakin lama. Hasil implementasi kontroler SMC yang digunakan terjadi error ± 6,6% pada kecepatan 300 rpm sedangkan pada kecepatan 800 rpm dan 200 rpm terjadi error ± 2,5%. Sehingga Tugas Akhir ini dapat membantu meningkatkan efisiensi mesin sentrifugal pada pabrik gula.

  1. A new fractional-order sliding mode controller via a nonlinear disturbance observer for a class of dynamical systems with mismatched disturbances.

    Science.gov (United States)

    Pashaei, Shabnam; Badamchizadeh, Mohammadali

    2016-07-01

    This paper investigates the stabilization and disturbance rejection for a class of fractional-order nonlinear dynamical systems with mismatched disturbances. To fulfill this purpose a new fractional-order sliding mode control (FOSMC) based on a nonlinear disturbance observer is proposed. In order to design the suitable fractional-order sliding mode controller, a proper switching surface is introduced. Afterward, by using the sliding mode theory and Lyapunov stability theory, a robust fractional-order control law via a nonlinear disturbance observer is proposed to assure the existence of the sliding motion in finite time. The proposed fractional-order sliding mode controller exposes better control performance, ensures fast and robust stability of the closed-loop system, eliminates the disturbances and diminishes the chattering problem. Finally, the effectiveness of the proposed fractional-order controller is depicted via numerical simulation results of practical example and is compared with some other controllers. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Slide 1

    Indian Academy of Sciences (India)

    Natural Disasters & Floods · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Indira Gandhi Canal in Rajasthan · Slide 12 · Epidemic Strains · Parasite strains in India · Questions · Slide 16 · Slide 17 · Slide 18 · Slide 19 · Slide 20 · Plasmodium falciparum CQ RESISTANCE TRANSPORTER PROTEIN (PfCRT) · pfcrt mutations.

  3. Parameter estimation and interval type-2 fuzzy sliding mode control of a z-axis MEMS gyroscope.

    Science.gov (United States)

    Fazlyab, Mahyar; Pedram, Maysam Zamani; Salarieh, Hassan; Alasty, Aria

    2013-11-01

    This paper reports a hybrid intelligent controller for application in single axis MEMS vibratory gyroscopes. First, unknown parameters of a micro gyroscope including unknown time varying angular velocity are estimated online via normalized continuous time least mean squares algorithm. Then, an additional interval type-2 fuzzy sliding mode control is incorporated in order to match the resonant frequencies and to compensate for undesired mechanical couplings. The main advantage of this control strategy is its robustness to parameters uncertainty, external disturbance and measurement noise. Consistent estimation of parameters is guaranteed and stability of the closed-loop system is proved via the Lyapunov stability theorem. Finally, numerical simulation is done in order to validate the effectiveness of the proposed method, both for a constant and time-varying angular rate. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  4. A Hybrid Scheme Motion Controller by Sliding Mode and Two-Degree-of-Freedom Controls to Minimize the Chattering

    Directory of Open Access Journals (Sweden)

    Chiu-Keng Lai

    2014-01-01

    Full Text Available Sliding mode control (SMC is rapped for the chattering due to high gain control. However, high gain control causes the system robust. For developing a system with robustness of SMC, a servo motor motion controller combining the two-degree-of-freedom (2DOF system and SMC is proposed. The discussed motion type is point-to-point control with the constraint of trapezoid velocity profile. SMC is designed to guide the motor motion to follow a predefined trail, and the inner 2DOF system is used to compensate the deterioration due to the adoption of load observer. The proposed hybrid system is realized on a PC-based motion controller, and the validness is verified by simulation and experimental results.

  5. Design of Nonlinear Robust Damping Controller for Power Oscillations Suppressing Based on Backstepping-Fractional Order Sliding Mode

    Directory of Open Access Journals (Sweden)

    Cheng Liu

    2017-05-01

    Full Text Available In this paper, a novel nonlinear robust damping controller is proposed to suppress power oscillation in interconnected power systems. The proposed power oscillation damping controller exhibits good nonlinearity and robustness. It can consider the strong nonlinearity of power oscillation and uncertainty of its model. First, through differential homeomorphic mapping, a mathematical model of the system can be transformed into the Brunovsky standard. Next, an extended state observer (ESO estimated and compensated for model errors and external disturbances as well as uncertain factors to achieve dynamic linearization of the nonlinear model. A power oscillation damping controller for interconnected power systems was designed on a backstepping-fractional order sliding mode variable structure control theory (BFSMC. Compared with traditional methods, the controller exhibits good dynamic performance and strong robustness. Simulations involving a four-generator two-area and partial test system of Northeast China were conducted under various disturbances to prove the effectiveness and robustness of the proposed damping control method.

  6. Synchronization between integer-order chaotic systems and a class of fractional-order chaotic systems via sliding mode control.

    Science.gov (United States)

    Chen, Diyi; Zhang, Runfan; Sprott, J C; Chen, Haitao; Ma, Xiaoyi

    2012-06-01

    In this paper, we focus on the synchronization between integer-order chaotic systems and a class of fractional-order chaotic system using the stability theory of fractional-order systems. A new sliding mode method is proposed to accomplish this end for different initial conditions and number of dimensions. More importantly, the vector controller is one-dimensional less than the system. Furthermore, three examples are presented to illustrate the effectiveness of the proposed scheme, which are the synchronization between a fractional-order Chen chaotic system and an integer-order T chaotic system, the synchronization between a fractional-order hyperchaotic system based on Chen's system and an integer-order hyperchaotic system, and the synchronization between a fractional-order hyperchaotic system based on Chen's system and an integer-order Lorenz chaotic system. Finally, numerical results are presented and are in agreement with theoretical analysis.

  7. The application of chattering-free sliding mode controller in coupled tank liquid-level control system

    Energy Technology Data Exchange (ETDEWEB)

    Derdiyok, Adnan; Basci, Abdullah [Ataturk University, Erzurum (Turkmenistan)

    2013-03-15

    A chattering-free sliding mode controller (CFSMC) is proposed to realize level position control of liquid level system for two coupled water tanks, as is often encountered in practical process control. The controller is used due to its robustness against large parameter variation, disturbances rejection and reduction in chattering. Experimentation of the coupled tank system is realized in two different configurations: configuration 1 and configuration 2. In configuration 1, the water level in the top tank is controlled by a pump. In 2, the water level in the bottom tank is controlled by the water flow coming out of the top tank. The validity of the proposed controller is verified by means of a practical testing on an experimental liquid level control device.

  8. Analysis and Design of a DSTATCOM Based on Sliding Mode Control Strategy for Improvement of Voltage Sag in Distribution Systems

    Directory of Open Access Journals (Sweden)

    Ghazanfar Shahgholian

    2016-07-01

    Full Text Available Voltage sag is considered to be the most serious problem of power quality. It is caused by faults in the power system or by the starting of large induction motors. Voltage sag causes about 80% of the power quality problems in power systems. One of the main reasons for voltage sag is short circuit fault, which can be compensated for by a distribution static compensator (DSTATCOM as an efficient and economical flexible AC transmission system (FACTS device. In this paper, compensation of this voltage sag using DSTATCOM is reviewed, in which a sliding mode control (SMC technique is employed. The results of this control system are compared with a P+Resonant control system. It will be shown that this control system is able to compensate the voltage sag over a broader range compared to other common control systems. Simulation results are obtained using PSCAD/EMTDC software and compared to that of a similar method.

  9. Sliding mode controller gain adaptation and chattering reduction techniques for DSP-based PM DC motor drives

    DEFF Research Database (Denmark)

    Dal, Mehmet; Teodorescu, Remus

    2011-01-01

    In order to achieve and maintain the prospective benefits of sliding mode control (SMC) methodology, the phenomenon known as “chattering”, the main obstacle encountered in real-time applications, has to be suppressed. In this study, two promising switching control gain adaptation and chattering...... in order to find the best solution for chattering reduction. To find a practical solution a tunable low-pass filter (LPF) was used to average the discontinuous control term. The validity of the existing conditions for the gain adaptation methods are examined and observer gain value was determined through...... simulations. To demonstrate the effectiveness of each method, several experiments were performed on a DSP-based PM DC motor drive system. Then, the newly proposed combinations of these methods were implemented. The hardware implementation results are comparatively presented and discussed....

  10. Simulation to Implementation as Good Practices for Teaching Power Electronics to Undergraduate Students: Fuzzy Sliding Mode Control for DC Motors

    Directory of Open Access Journals (Sweden)

    Paul Cepeda

    2014-01-01

    Full Text Available How can students be given experience in the confused realities of engineering processes? How can undergraduate students be convinced that processes can be analyzed and improved? Computer simulations properly designed and applied could answer these challenges revolutionizing education in Power Electronics. In recent years, computer simulation has been commonly used in education to motivate students in their learning and help teachers to improve their teaching level. The present paper focuses on developing a speed controller for DC motors starting from theoretical aspects, passing through simulations, and finally reaching a control prototype. The control theory is based on a nonlinear technique known as Sliding Mode Control (SMC involving artificial intelligence for optimization such as Fuzzy Logic (FL, Adaptive Neurofuzzy Inference Systems (ANFIS, and Genetic Algorithms (GAs.

  11. Continuous Finite-Time Terminal Sliding Mode IDA-PBC Design for PMSM with the Port-Controlled Hamiltonian Model

    Directory of Open Access Journals (Sweden)

    Shuanghe Yu

    2013-01-01

    Full Text Available Finite-time control scheme for speed regulation of permanent magnet synchronous motor (PMSM is investigated under the port-controlled Hamiltonian (PCH, terminal sliding mode (TSM, and fast TSM stabilization theories. The desired equilibrium is assigned to the PCH structure model of PMSM by maximum torque per ampere (MTPA principle, and the desired Hamiltonian function of state error is constructed in the form of fractional power structure as TSM and fast TSM, respectively. Finite-time TSM and fast TSM controllers are designed via interconnection and damping assignment passivity-based control (IDA-PBC methodology, respectively, and the finite-time stability of the desired equilibrium point is also achieved under the PCH framework. Simulation results validate the improved performance of the presented scheme.

  12. Zero-Disturbance Control of Free-Floating Space Manipulators Using Integral-Type Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Heping Li

    2015-01-01

    Full Text Available A free-floating space manipulator is an underactuated system, of which the spacecraft is permitted to rotate freely in response to the manipulator motions. The dynamic coupling property between the spacecraft and the manipulator makes motion control of such systems a significant challenge. In the paper, a zero-disturbance control method for free-floating space manipulators operating in task space is presented. An explicit direct relationship between the spacecraft attitude quaternions and the manipulator joint variables is established using nonholonomic constraints of the angular momentum conservation. By this means the kinematic redundancy of the system is used to adjust the spacecraft attitude. An integral-type sliding mode controller with adaptive switching gains is developed for coordinated motion control of the spacecraft and the manipulator. Simulations on three-link planar model show that the spacecraft remains undisturbed during the whole process of manipulations, which confirms the effectiveness of the proposed method.

  13. Real time implementation of adaptive sliding mode observer based speed sensor less vector control of induction motor

    Directory of Open Access Journals (Sweden)

    Negadi Karim

    2010-01-01

    Full Text Available Sensor less induction motor drives are widely used in industry for their reliability and flexibility. However, rotor flux and speed sensors are required for vector control of induction motor. These sensors are sources of trouble, mainly in hostile environments, and their application reduces the drive robustness. The cost of the sensors is not also negligible. All the reasons lead to development of different sensor less methods for rotor flux and mechanical speed estimation in electrical drives. The paper deals with the speed estimators for applications in sensor less induction motor drive with vector control, which are based on application of model adaptive, based sliding mode observer methods. This paper presents the development and DSP implementation of the speed estimators for applications in sensor less drives with induction motor.

  14. Synchronization between a novel class of fractional-order and integer-order chaotic systems via a sliding mode controller

    Science.gov (United States)

    Chen, Di-Yi; Zhang, Run-Fan; Ma, Xiao-Yi; Wang, Juan

    2012-12-01

    In order to figure out the dynamical behaviour of a fractional-order chaotic system and its relation to an integer-order chaotic system, in this paper we investigate the synchronization between a class of fractional-order chaotic systems and integer-order chaotic systems via sliding mode control method. Stability analysis is performed for the proposed method based on stability theorems in the fractional calculus. Moreover, three typical examples are carried out to show that the synchronization between fractional-order chaotic systems and integer-orders chaotic systems can be achieved. Our theoretical findings are supported by numerical simulation results. Finally, results from numerical computations and theoretical analysis are demonstrated to be a perfect bridge between fractional-order chaotic systems and integer-order chaotic systems.

  15. Synchronization between integer-order chaotic systems and a class of fractional-order chaotic systems via sliding mode control

    Science.gov (United States)

    Chen, Diyi; Zhang, Runfan; Sprott, J. C.; Chen, Haitao; Ma, Xiaoyi

    2012-06-01

    In this paper, we focus on the synchronization between integer-order chaotic systems and a class of fractional-order chaotic system using the stability theory of fractional-order systems. A new sliding mode method is proposed to accomplish this end for different initial conditions and number of dimensions. More importantly, the vector controller is one-dimensional less than the system. Furthermore, three examples are presented to illustrate the effectiveness of the proposed scheme, which are the synchronization between a fractional-order Chen chaotic system and an integer-order T chaotic system, the synchronization between a fractional-order hyperchaotic system based on Chen's system and an integer-order hyperchaotic system, and the synchronization between a fractional-order hyperchaotic system based on Chen's system and an integer-order Lorenz chaotic system. Finally, numerical results are presented and are in agreement with theoretical analysis.

  16. Online Fault Detection of Permanent Magnet Demagnetization for IPMSMs by Nonsingular Fast Terminal-Sliding-Mode Observer

    Directory of Open Access Journals (Sweden)

    Kai-Hui Zhao

    2014-12-01

    Full Text Available To prevent irreversible demagnetization of a permanent magnet (PM for interior permanent magnet synchronous motors (IPMSMs by flux-weakening control, a robust PM flux-linkage nonsingular fast terminal-sliding-mode observer (NFTSMO is proposed to detect demagnetization faults. First, the IPMSM mathematical model of demagnetization is presented. Second, the construction of the NFTSMO to estimate PM demagnetization faults in IPMSM is described, and a proof of observer stability is given. The fault decision criteria and fault-processing method are also presented. Finally, the proposed scheme was simulated using MATLAB/Simulink and implemented on the RT-LABplatform. A number of robustness tests have been carried out. The scheme shows good performance in spite of speed fluctuations, torque ripples and the uncertainties of stator resistance.

  17. Adaptive disturbance compensation finite control set optimal control for PMSM systems based on sliding mode extended state observer

    Science.gov (United States)

    Wu, Yun-jie; Li, Guo-fei

    2018-01-01

    Based on sliding mode extended state observer (SMESO) technique, an adaptive disturbance compensation finite control set optimal control (FCS-OC) strategy is proposed for permanent magnet synchronous motor (PMSM) system driven by voltage source inverter (VSI). So as to improve robustness of finite control set optimal control strategy, a SMESO is proposed to estimate the output-effect disturbance. The estimated value is fed back to finite control set optimal controller for implementing disturbance compensation. It is indicated through theoretical analysis that the designed SMESO could converge in finite time. The simulation results illustrate that the proposed adaptive disturbance compensation FCS-OC possesses better dynamical response behavior in the presence of disturbance.

  18. Sensorless control of ship propulsion interior permanent magnet synchronous motor based on a new sliding mode observer.

    Science.gov (United States)

    Ren, Jun-Jie; Liu, Yan-Cheng; Wang, Ning; Liu, Si-Yuan

    2015-01-01

    This paper proposes a sensorless speed control strategy for ship propulsion interior permanent magnet synchronous motor (IPMSM) based on a new sliding-mode observer (SMO). In the SMO the low-pass filter and the method of arc-tangent calculation of extended electromotive force (EMF) or phase-locked loop (PLL) technique are not used. The calculation of the rotor speed is deduced from the Lyapunov function stability analysis. In order to reduce system chattering, sigmoid functions with switching gains being adaptively updated by fuzzy logic systems are innovatively incorporated into the SMO. Finally, simulation results for a 4.088 MW ship propulsion IPMSM and experimental results from a 7.5 kW IPMSM drive are provided to verify the effectiveness of the proposed SMO method. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Online Fault Detection of Permanent Magnet Demagnetization for IPMSMs by Nonsingular Fast Terminal-Sliding-Mode Observer

    Science.gov (United States)

    Zhao, Kai-Hui; Chen, Te-Fang; Zhang, Chang-Fan; He, Jing; Huang, Gang

    2014-01-01

    To prevent irreversible demagnetization of a permanent magnet (PM) for interior permanent magnet synchronous motors (IPMSMs) by flux-weakening control, a robust PM flux-linkage nonsingular fast terminal-sliding-mode observer (NFTSMO) is proposed to detect demagnetization faults. First, the IPMSM mathematical model of demagnetization is presented. Second, the construction of the NFTSMO to estimate PM demagnetization faults in IPMSM is described, and a proof of observer stability is given. The fault decision criteria and fault-processing method are also presented. Finally, the proposed scheme was simulated using MATLAB/Simulink and implemented on the RT-LAB platform. A number of robustness tests have been carried out. The scheme shows good performance in spite of speed fluctuations, torque ripples and the uncertainties of stator resistance. PMID:25490582

  20. Extended State Observer Based Adaptive Back-Stepping Sliding Mode Control of Electronic Throttle in Transportation Cyber-Physical Systems

    Directory of Open Access Journals (Sweden)

    Yongfu Li

    2015-01-01

    Full Text Available Considering the high accuracy requirement of information exchange via vehicle-to-vehicle (V2V communications, an extended state observer (ESO is designed to estimate the opening angle change of an electronic throttle (ET, wherein the emphasis is placed on the nonlinear uncertainties of stick-slip friction and spring in the system as well as the existence of external disturbance. In addition, a back-stepping sliding mode controller incorporating an adaptive control law is presented, and the stability and robustness of the system are analyzed using Lyapunov technique. Finally, numerical experiments are conducted using simulation. The results show that, compared with back-stepping control (BSC, the proposed controller achieves superior performance in terms of the steady-state error and rising time.

  1. Comparative Performance Analysis of Sliding Mode and Q-Controller Algorithms for Buck Converter

    Science.gov (United States)

    Pati, Nivedita

    2017-08-01

    The switched mode dc-dc converters are some of the simplest power electronic circuits which have received an increasing deal of interest in many areas due to their high efficiency and small size. These converters are non-linear and time-variant in nature; hence the analysis, control and stabilization are the main factors that need to be considered. Many control methodology are used for control of switch mode dc-dc converters but the optimum one is always in demand. This paper presents the linearization of the Buck converter model and a comparison between a linear and non-linear control algorithms for better output voltage regulation along with robustness to change in input voltage and load parameters. The computer -aided design software tool Matlab/Simulink is used for the simulations and the results are presented.

  2. Convolutional neural networks for an automatic classification of prostate tissue slides with high-grade Gleason score

    Science.gov (United States)

    Jiménez del Toro, Oscar; Atzori, Manfredo; Otálora, Sebastian; Andersson, Mats; Eurén, Kristian; Hedlund, Martin; Rönnquist, Peter; Müller, Henning

    2017-03-01

    The Gleason grading system was developed for assessing prostate histopathology slides. It is correlated to the outcome and incidence of relapse in prostate cancer. Although this grading is part of a standard protocol performed by pathologists, visual inspection of whole slide images (WSIs) has an inherent subjectivity when evaluated by different pathologists. Computer aided pathology has been proposed to generate an objective and reproducible assessment that can help pathologists in their evaluation of new tissue samples. Deep convolutional neural networks are a promising approach for the automatic classification of histopathology images and can hierarchically learn subtle visual features from the data. However, a large number of manual annotations from pathologists are commonly required to obtain sufficient statistical generalization when training new models that can evaluate the daily generated large amounts of pathology data. A fully automatic approach that detects prostatectomy WSIs with high-grade Gleason score is proposed. We evaluate the performance of various deep learning architectures training them with patches extracted from automatically generated regions-of-interest rather than from manually segmented ones. Relevant parameters for training the deep learning model such as size and number of patches as well as the inclusion or not of data augmentation are compared between the tested deep learning architectures. 235 prostate tissue WSIs with their pathology report from the publicly available TCGA data set were used. An accuracy of 78% was obtained in a balanced set of 46 unseen test images with different Gleason grades in a 2-class decision: high vs. low Gleason grade. Grades 7-8, which represent the boundary decision of the proposed task, were particularly well classified. The method is scalable to larger data sets with straightforward re-training of the model to include data from multiple sources, scanners and acquisition techniques. Automatically

  3. Lyapunov Based-Distributed Fuzzy-Sliding Mode Control for Building Integrated-DC Microgrid with Plug-in Electric Vehicle

    DEFF Research Database (Denmark)

    Ghiasi, Mohammad Iman; Aliakbar Golkar, Masoud; Hajizadeh, Amin

    2017-01-01

    This paper presents a distributed control strategy based on Fuzzy-Sliding Mode Control (FSMC) for power control of an infrastructure integrated with a DC-Microgrid, which includes photovoltaic, fuel cell and energy storage systems with Plug-in Electric Vehicles (PEVs). In order to implement...

  4. Slide 1

    Indian Academy of Sciences (India)

    Potency of Stem Cells · Slide 3 · Slide 4 · Slide 5 · World Wide Clinical trials using MSCs · Slide 7 · Bone Marrow derived Human MSCs (hMSC) in culture · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Fetal MSCs · Morphology of murine fetal heart derived stem cells (fHSCs) · Growth Kinetics of fHSCs · Phenotype of ...

  5. A Robust Fuzzy Sliding Mode Controller Synthesis Applied on Boost DC-DC Converter Power Supply for Electric Vehicle Propulsion System

    Directory of Open Access Journals (Sweden)

    Boumediène Allaoua

    2013-01-01

    Full Text Available The development of electric vehicles power electronics system control comprising of DC-AC inverters and DC-DC converters takes a great interest of researchers in the modern industry. A DC-AC inverter supplies the high power electric vehicle motors torques of the propulsion system and utility loads, whereas a DC-DC converter supplies conventional low-power, low-voltage loads. However, the need for high power bidirectional DC-DC converters in future electric vehicles has led to the development of many new topologies of DC-DC converters. Nonlinear control of power converters is an active area of research in the fields of power electronics. This paper focuses on a fuzzy sliding mode strategy (FSMS as a control strategy for boost DC-DC converter power supply for electric vehicle. The proposed fuzzy controller specifies changes in the control signal based on the surface and the surface change knowledge to satisfy the sliding mode stability and attraction conditions. The performances of the proposed fuzzy sliding controller are compared to those obtained by a classical sliding mode controller. The satisfactory simulation results show the efficiency of the proposed control law which reduces the chattering phenomenon. Moreover, the obtained results prove the robustness of the proposed control law against variation of the load resistance and the input voltage of the studied converter.

  6. Adaptive super-twisting sliding mode control for a three-phase single-stage grid-connected differential boost inverter based photovoltaic system.

    Science.gov (United States)

    Pati, Akshaya K; Sahoo, N C

    2017-07-01

    This paper presents an adaptive super-twisting sliding mode control (STC) along with double-loop control for voltage tracking performance of three-phase differential boost inverter and DC-link capacitor voltage regulation in grid-connected PV system. The effectiveness of the proposed control strategies are demonstrated under realistic scenarios such as variations in solar insolation, load power demand, grid voltage, and transition from grid-connected to standalone mode etc. Additional supplementary power quality control functions such as harmonic compensation, and reactive power management are also investigated with the proposed control strategy. The results are compared with conventional proportional-integral controller, and PWM sliding mode controller. The system performance is evaluated in simulation and in real-time. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Disturbance-Estimated Adaptive Backstepping Sliding Mode Control of a Pneumatic Muscles-Driven Ankle Rehabilitation Robot.

    Science.gov (United States)

    Ai, Qingsong; Zhu, Chengxiang; Zuo, Jie; Meng, Wei; Liu, Quan; Xie, Sheng Q; Yang, Ming

    2017-12-28

    A rehabilitation robot plays an important role in relieving the therapists' burden and helping patients with ankle injuries to perform more accurate and effective rehabilitation training. However, a majority of current ankle rehabilitation robots are rigid and have drawbacks in terms of complex structure, poor flexibility and lack of safety. Taking advantages of pneumatic muscles' good flexibility and light weight, we developed a novel two degrees of freedom (2-DOF) parallel compliant ankle rehabilitation robot actuated by pneumatic muscles (PMs). To solve the PM's nonlinear characteristics during operation and to tackle the human-robot uncertainties in rehabilitation, an adaptive backstepping sliding mode control (ABS-SMC) method is proposed in this paper. The human-robot external disturbance can be estimated by an observer, who is then used to adjust the robot output to accommodate external changes. The system stability is guaranteed by the Lyapunov stability theorem. Experimental results on the compliant ankle rehabilitation robot show that the proposed ABS-SMC is able to estimate the external disturbance online and adjust the control output in real time during operation, resulting in a higher trajectory tracking accuracy and better response performance especially in dynamic conditions.

  8. Accurate torque-sensorless control approach for interior permanent-magnet synchronous machine based on cascaded sliding mode observer

    Directory of Open Access Journals (Sweden)

    Kai-Hui Zhao

    2017-06-01

    Full Text Available To improve the accuracy of torque control for vector control of interior permanent-magnet synchronous machine (IPMSM, this study proposes a torque-sensorless control method based on cascaded sliding mode observer (SMO. First, the active flux model is discussed, which converts the model of IPMSM into the equivalent model of surface-mounted permanent-magnet synchronous machine. Second, to reduce chattering caused by system parameters variations and external disturbances, the cascaded observer is designed, which is composed of a variable gain adaptive SMO and an active flux SMO. The variable gain adaptive SMO is designed to estimate the speed, rotor position and stator resistance in the d–q reference frame. The active flux SMO is designed to estimate the active flux and torque in the α–β reference frame. Global asymptotic stability of the observers is guaranteed by the Lyapunov stability analysis. Finally, simulations and experiments are carried out to verify the effectiveness of the proposed control scheme.

  9. Short-Circuit Fault Tolerant Control of a Wind Turbine Driven Induction Generator Based on Sliding Mode Observers

    Directory of Open Access Journals (Sweden)

    Takwa Sellami

    2017-10-01

    Full Text Available The installed energy production capacity of wind turbines is growing intensely on a global scale, making the reliability of wind turbine subsystems of greater significance. However, many faults like Inter-Turn Short-Circuit (ITSC may affect the turbine generator and quickly lead to a decline in supplied power quality. In this framework, this paper proposes a Sliding Mode Observer (SMO-based Fault Tolerant Control (FTC scheme for Induction Generator (IG-based variable-speed grid-connected wind turbines. First, the dynamic models of the wind turbine subsystems were developed. The control schemes were elaborated based on the Maximum Power Point Tracking (MPPT method and Indirect Rotor Flux Oriented Control (IRFOC method. The grid control was also established by regulating the active and reactive powers. The performance of the wind turbine system and the stability of injected power to the grid were hence analyzed under both healthy and faulty conditions. The robust developed SMO-based Fault Detection and Isolation (FDI scheme was proved to be fast and efficient for ITSC detection and localization.Afterwards, SMO were involved in scheming the FTC technique. Accordingly, simulation results assert the efficacy of the proposed ITSC FTC method for variable-speed wind turbines with faulty IG in protecting the subsystems from damage and ensuring continuous connection of the wind turbine to the grid during ITSC faults, hence maintaining power quality.

  10. Adaptive Neuro-Fuzzy Control of a Spherical Rolling Robot Using Sliding-Mode-Control-Theory-Based Online Learning Algorithm.

    Science.gov (United States)

    Kayacan, Erkan; Kayacan, Erdal; Ramon, Herman; Saeys, Wouter

    2013-02-01

    As a model is only an abstraction of the real system, unmodeled dynamics, parameter variations, and disturbances can result in poor performance of a conventional controller based on this model. In such cases, a conventional controller cannot remain well tuned. This paper presents the control of a spherical rolling robot by using an adaptive neuro-fuzzy controller in combination with a sliding-mode control (SMC)-theory-based learning algorithm. The proposed control structure consists of a neuro-fuzzy network and a conventional controller which is used to guarantee the asymptotic stability of the system in a compact space. The parameter updating rules of the neuro-fuzzy system using SMC theory are derived, and the stability of the learning is proven using a Lyapunov function. The simulation results show that the control scheme with the proposed SMC-theory-based learning algorithm is able to not only eliminate the steady-state error but also improve the transient response performance of the spherical rolling robot without knowing its dynamic equations.

  11. Nonlinear observation of internal states of fuel cell cathode utilizing a high-order sliding-mode algorithm

    Science.gov (United States)

    Xu, Liangfei; Hu, Junming; Cheng, Siliang; Fang, Chuan; Li, Jianqiu; Ouyang, Minggao; Lehnert, Werner

    2017-07-01

    A scheme for designing a second-order sliding-mode (SOSM) observer that estimates critical internal states on the cathode side of a polymer electrolyte membrane (PEM) fuel cell system is presented. A nonlinear, isothermal dynamic model for the cathode side and a membrane electrolyte assembly are first described. A nonlinear observer topology based on an SOSM algorithm is then introduced, and equations for the SOSM observer deduced. Online calculation of the inverse matrix produces numerical errors, so a modified matrix is introduced to eliminate the negative effects of these on the observer. The simulation results indicate that the SOSM observer performs well for the gas partial pressures and air stoichiometry. The estimation results follow the simulated values in the model with relative errors within ± 2% at stable status. Large errors occur during the fast dynamic processes (<1 s). Moreover, the nonlinear observer shows good robustness against variations in the initial values of the internal states, but less robustness against variations in system parameters. The partial pressures are more sensitive than the air stoichiometry to system parameters. Finally, the order of effects of parameter uncertainties on the estimation results is outlined and analyzed.

  12. Symmetric caging formation for convex polygonal object transportation by multiple mobile robots based on fuzzy sliding mode control.

    Science.gov (United States)

    Dai, Yanyan; Kim, YoonGu; Wee, SungGil; Lee, DongHa; Lee, SukGyu

    2016-01-01

    In this paper, the problem of object caging and transporting is considered for multiple mobile robots. With the consideration of minimizing the number of robots and decreasing the rotation of the object, the proper points are calculated and assigned to the multiple mobile robots to allow them to form a symmetric caging formation. The caging formation guarantees that all of the Euclidean distances between any two adjacent robots are smaller than the minimal width of the polygonal object so that the object cannot escape. In order to avoid collision among robots, the parameter of the robots radius is utilized to design the caging formation, and the A⁎ algorithm is used so that mobile robots can move to the proper points. In order to avoid obstacles, the robots and the object are regarded as a rigid body to apply artificial potential field method. The fuzzy sliding mode control method is applied for tracking control of the nonholonomic mobile robots. Finally, the simulation and experimental results show that multiple mobile robots are able to cage and transport the polygonal object to the goal position, avoiding obstacles. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  13. Chaos Suppression of an Electrically Actuated Microresonator Based on Fractional-Order Nonsingular Fast Terminal Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Jianxin Han

    2017-01-01

    Full Text Available This paper focuses on chaos suppression strategy of a microresonator actuated by two symmetrical electrodes. Dynamic behavior of this system under the case where the origin is the only stable equilibrium is investigated first. Numerical simulations reveal that system may exhibit chaotic motion under certain excitation conditions. Then, bifurcation diagrams versus amplitude or frequency of AC excitation are drawn to grasp system dynamics nearby its natural frequency. Results show that the vibration is complex and may exhibit period-doubling bifurcation, chaotic motion, or dynamic pull-in instability. For the suppression of chaos, a novel control algorithm, based on an integer-order nonsingular fast terminal sliding mode and a fractional-order switching law, is proposed. Fractional Lyapunov Stability Theorem is used to guarantee the asymptotic stability of the system. Finally, numerical results with both fractional-order and integer-order control laws show that our proposed control law is effective in controlling chaos with system uncertainties and external disturbances.

  14. Loop tuning with specification on gain and phase margins via modified second-order sliding mode control algorithm

    Science.gov (United States)

    Boiko, I. M.

    2012-01-01

    The modified second-order sliding mode algorithm is used for controller tuning. Namely, the modified suboptimal algorithm-based test (modified SOT) and non-parametric tuning rules for proportional-integral-derivative (PID) controllers are presented in this article. In the developed method of test and tuning, the idea of coordinated selection of the test parameters and the controller tuning parameters is introduced. The proposed approach allows for the formulation of simple non-parametric tuning rules for PID controllers that provide desired amplitude or phase margins exactly. In the modified SOT, the frequency of the self-excited oscillations can be generated equal to either the phase crossover frequency or the magnitude crossover frequency of the open-loop system frequency response (including a future PID controller) - depending on the tuning method choice. The first option will provide tuning with specification on gain margin, and the second option will ensure tuning with specification on phase margin. Tuning rules for a PID controller and simulation examples are provided.

  15. Sliding Mode Observer-Based Current Sensor Fault Reconstruction and Unknown Load Disturbance Estimation for PMSM Driven System.

    Science.gov (United States)

    Zhao, Kaihui; Li, Peng; Zhang, Changfan; Li, Xiangfei; He, Jing; Lin, Yuliang

    2017-12-06

    This paper proposes a new scheme of reconstructing current sensor faults and estimating unknown load disturbance for a permanent magnet synchronous motor (PMSM)-driven system. First, the original PMSM system is transformed into two subsystems; the first subsystem has unknown system load disturbances, which are unrelated to sensor faults, and the second subsystem has sensor faults, but is free from unknown load disturbances. Introducing a new state variable, the augmented subsystem that has sensor faults can be transformed into having actuator faults. Second, two sliding mode observers (SMOs) are designed: the unknown load disturbance is estimated by the first SMO in the subsystem, which has unknown load disturbance, and the sensor faults can be reconstructed using the second SMO in the augmented subsystem, which has sensor faults. The gains of the proposed SMOs and their stability analysis are developed via the solution of linear matrix inequality (LMI). Finally, the effectiveness of the proposed scheme was verified by simulations and experiments. The results demonstrate that the proposed scheme can reconstruct current sensor faults and estimate unknown load disturbance for the PMSM-driven system.

  16. Sliding Mode Observer-Based Current Sensor Fault Reconstruction and Unknown Load Disturbance Estimation for PMSM Driven System

    Directory of Open Access Journals (Sweden)

    Kaihui Zhao

    2017-12-01

    Full Text Available This paper proposes a new scheme of reconstructing current sensor faults and estimating unknown load disturbance for a permanent magnet synchronous motor (PMSM-driven system. First, the original PMSM system is transformed into two subsystems; the first subsystem has unknown system load disturbances, which are unrelated to sensor faults, and the second subsystem has sensor faults, but is free from unknown load disturbances. Introducing a new state variable, the augmented subsystem that has sensor faults can be transformed into having actuator faults. Second, two sliding mode observers (SMOs are designed: the unknown load disturbance is estimated by the first SMO in the subsystem, which has unknown load disturbance, and the sensor faults can be reconstructed using the second SMO in the augmented subsystem, which has sensor faults. The gains of the proposed SMOs and their stability analysis are developed via the solution of linear matrix inequality (LMI. Finally, the effectiveness of the proposed scheme was verified by simulations and experiments. The results demonstrate that the proposed scheme can reconstruct current sensor faults and estimate unknown load disturbance for the PMSM-driven system.

  17. Performance Evaluation of an Anti-Lock Braking System for Electric Vehicles with a Fuzzy Sliding Mode Controller

    Directory of Open Access Journals (Sweden)

    Jingang Guo

    2014-10-01

    Full Text Available Traditional friction braking torque and motor braking torque can be used in braking for electric vehicles (EVs. A sliding mode controller (SMC based on the exponential reaching law for the anti-lock braking system (ABS is developed to maintain the optimal slip value. Parameter optimizing is applied to the reaching law by fuzzy logic control (FLC. A regenerative braking algorithm, in which the motor torque is taken full advantage of, is adopted to distribute the braking force between the motor braking and the hydraulic braking. Simulations were carried out with Matlab/Simulink. By comparing with a conventional Bang-bang ABS controller, braking stability and passenger comfort is improved with the proposed SMC controller, and the chatting phenomenon is reduced effectively with the parameter optimizing by FLC. With the increasing proportion of the motor braking torque, the tracking of the slip ratio is more rapid and accurate. Furthermore, the braking distance is shortened and the conversion energy is enhanced.

  18. SLIDE: automatic spine level identification system using a deep convolutional neural network.

    Science.gov (United States)

    Hetherington, Jorden; Lessoway, Victoria; Gunka, Vit; Abolmaesumi, Purang; Rohling, Robert

    2017-07-01

    Percutaneous spinal needle insertion procedures often require proper identification of the vertebral level to effectively and safely deliver analgesic agents. The current clinical method involves "blind" identification of the vertebral level through manual palpation of the spine, which has only 30% reported accuracy. Therefore, there is a need for better anatomical identification prior to needle insertion. A real-time system was developed to identify the vertebral level from a sequence of ultrasound images, following a clinical imaging protocol. The system uses a deep convolutional neural network (CNN) to classify transverse images of the lower spine. Several existing CNN architectures were implemented, utilizing transfer learning, and compared for adequacy in a real-time system. In the system, the CNN output is processed, using a novel state machine, to automatically identify vertebral levels as the transducer moves up the spine. Additionally, a graphical display was developed and integrated within 3D Slicer. Finally, an augmented reality display, projecting the level onto the patient's back, was also designed. A small feasibility study [Formula: see text] evaluated performance. The proposed CNN successfully discriminates ultrasound images of the sacrum, intervertebral gaps, and vertebral bones, achieving 88% 20-fold cross-validation accuracy. Seventeen of 20 test ultrasound scans had successful identification of all vertebral levels, processed at real-time speed (40 frames/s). A machine learning system is presented that successfully identifies lumbar vertebral levels. The small study on human subjects demonstrated real-time performance. A projection-based augmented reality display was used to show the vertebral level directly on the subject adjacent to the puncture site.

  19. Real-time altitude control for a quadrotor helicopter using a super-twisting controller based on high-order sliding mode observer

    Directory of Open Access Journals (Sweden)

    Ivan Gonzalez-Hernandez

    2017-01-01

    Full Text Available This article addresses the problem of altitude tracking for unmanned aircraft system when the altitude velocity is unknown, because in a practical implementation, the available sensors used to measure the vehicle’s altitude (barometer, global positioning system, laser, etc. do not provide the altitude velocity. We propose a control strategy based on both the super-twisting sliding mode controller as well as a high-order sliding mode observer to control and to estimate the altitude velocity, respectively. A comprehensive stability analysis for the combined controller–observer based on the Lyapunov stability theory is presented, ensuring the asymptotic convergence of the tracking error under external bounded disturbances. To demonstrate the performance and the effectiveness of the proposed solution, an extensive set of real-time experimental tests performed at outdoor environments is presented.

  20. Active fault tolerant control based on interval type-2 fuzzy sliding mode controller and non linear adaptive observer for 3-DOF laboratory helicopter.

    Science.gov (United States)

    Zeghlache, Samir; Benslimane, Tarak; Bouguerra, Abderrahmen

    2017-11-01

    In this paper, a robust controller for a three degree of freedom (3 DOF) helicopter control is proposed in presence of actuator and sensor faults. For this purpose, Interval type-2 fuzzy logic control approach (IT2FLC) and sliding mode control (SMC) technique are used to design a controller, named active fault tolerant interval type-2 Fuzzy Sliding mode controller (AFTIT2FSMC) based on non-linear adaptive observer to estimate and detect the system faults for each subsystem of the 3-DOF helicopter. The proposed control scheme allows avoiding difficult modeling, attenuating the chattering effect of the SMC, reducing the rules number of the fuzzy controller. Exponential stability of the closed loop is guaranteed by using the Lyapunov method. The simulation results show that the AFTIT2FSMC can greatly alleviate the chattering effect, providing good tracking performance, even in presence of actuator and sensor faults. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  1. SMA actuator material model with self-sensing and sliding-mode control; experiment and multibody dynamics model

    Science.gov (United States)

    Lambert, Tyler Ross; Gurley, Austin; Beale, David

    2017-03-01

    Shape memory alloys (SMA) can be used to create actuators that are simple, high strength, and inexpensive. These benefits come at the cost of low electrical efficiency, moderate lifetime, and complex mechanical behavior that makes them difficult to design into new applications and products. To improve the integration of SMA actuators—in particular thin SMA wires heated by passing electric current through them—into modern mechanical applications, we have created tools for modeling SMA mechanical and thermal behavior in dynamic systems and under feedback controls. Thermo-electro-mechanical constitutive models are implemented in a multibody dynamics software where they are easily applied to an actuator emplaced in a multibody dynamic system. Mechanical behavior is modeled with 1D constitutive equations. The material state determines the electrical resistivity of the material which drives ohmic heating, while thermal cooling is based on a heat transfer analysis of thin cylinders. These models contain states which are very difficult to measure experimentally (such as crystal phase fraction) and thus provide insight into the material behavior and design that experimental results cannot offer. This thermomechanical model is used in conjunction with sliding mode control—historically difficult to simulate in numerically integrated models—to develop a working ball-on-a-beam setup in which the ball position is controlled via current passed through an SMA wire and with application of an original self-sensing method. The constitutive model is developed in the multibody dynamics software MSC ADAMS and validated through the simulation of the same system.

  2. Sliding mode control for generalized robust synchronization of mismatched fractional order dynamical systems and its application to secure transmission of voice messages.

    Science.gov (United States)

    Muthukumar, P; Balasubramaniam, P; Ratnavelu, K

    2017-07-26

    This paper proposes a generalized robust synchronization method for different dimensional fractional order dynamical systems with mismatched fractional derivatives in the presence of function uncertainty and external disturbance by a designing sliding mode controller. Based on the proposed theory of generalized robust synchronization criterion, a novel audio cryptosystem is proposed for sending or sharing voice messages secretly via insecure channel. Numerical examples are given to verify the potency of the proposed theories. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Real-Time Transportation Mode Identification Using Artificial Neural Networks Enhanced with Mode Availability Layers: A Case Study in Dubai

    Directory of Open Access Journals (Sweden)

    Young-Ji Byon

    2017-09-01

    Full Text Available Traditionally, departments of transportation (DOTs have dispatched probe vehicles with dedicated vehicles and drivers for monitoring traffic conditions. Emerging assisted GPS (AGPS and accelerometer-equipped smartphones offer new sources of raw data that arise from voluntarily-traveling smartphone users provided that their modes of transportation can correctly be identified. By introducing additional raster map layers that indicate the availability of each mode, it is possible to enhance the accuracy of mode detection results. Even in its simplest form, an artificial neural network (ANN excels at pattern recognition with a relatively short processing timeframe once it is properly trained, which is suitable for real-time mode identification purposes. Dubai is one of the major cities in the Middle East and offers unique environments, such as a high density of extremely high-rise buildings that may introduce multi-path errors with GPS signals. This paper develops real-time mode identification ANNs enhanced with proposed mode availability geographic information system (GIS layers, firstly for a universal mode detection and, secondly for an auto mode detection for the particular intelligent transportation system (ITS application of traffic monitoring, and compares the results with existing approaches. It is found that ANN-based real-time mode identification, enhanced by mode availability GIS layers, significantly outperforms the existing methods.

  4. Slide 1

    Indian Academy of Sciences (India)

    Problem 1: Direct Materials Procurement at GM · Slide 8 · Slide 9 · Slide 10 · Game Theory · Strategic Form Games (Normal Form Games) · Example : Prisoner's Dilemma · Dominant Strategy Equilibrium · Nash Equilibrium · Nash's Theorem · Slide 17 · Slide 18 · Example 1: Mechanism Design Fair Division of a Cake.

  5. Sampled-Data Synchronization of Markovian Coupled Neural Networks With Mode Delays Based on Mode-Dependent LKF.

    Science.gov (United States)

    Wang, Junyi; Zhang, Huaguang; Wang, Zhanshan; Liu, Zhenwei

    This paper investigates sampled-data synchronization problem of Markovian coupled neural networks with mode-dependent interval time-varying delays and aperiodic sampling intervals based on an enhanced input delay approach. A mode-dependent augmented Lyapunov-Krasovskii functional (LKF) is utilized, which makes the LKF matrices mode-dependent as much as possible. By applying an extended Jensen's integral inequality and Wirtinger's inequality, new delay-dependent synchronization criteria are obtained, which fully utilizes the upper bound on variable sampling interval and the sawtooth structure information of varying input delay. In addition, the desired stochastic sampled-data controllers can be obtained by solving a set of linear matrix inequalities. Finally, two examples are provided to demonstrate the feasibility of the proposed method.This paper investigates sampled-data synchronization problem of Markovian coupled neural networks with mode-dependent interval time-varying delays and aperiodic sampling intervals based on an enhanced input delay approach. A mode-dependent augmented Lyapunov-Krasovskii functional (LKF) is utilized, which makes the LKF matrices mode-dependent as much as possible. By applying an extended Jensen's integral inequality and Wirtinger's inequality, new delay-dependent synchronization criteria are obtained, which fully utilizes the upper bound on variable sampling interval and the sawtooth structure information of varying input delay. In addition, the desired stochastic sampled-data controllers can be obtained by solving a set of linear matrix inequalities. Finally, two examples are provided to demonstrate the feasibility of the proposed method.

  6. Slide 1

    Indian Academy of Sciences (India)

    Brewster angle microscopy (BAM) Images · Interaction of NPEA with DPPC: DSC · NPEA:DPPC mixtures: Phase Diagram from DSC data · Structures of Phases: 31P-NMR · Structures of Phases: SAXS · Long spacings from SAXS · Slide 38 · Slide 39 · Slide 40 · Slide 41 · Slide 42 · Slide 43 · Summary · THANKS TO ... Author: ...

  7. Governor Design for a Hydropower Plant with an Upstream Surge Tank by GA-Based Fuzzy Reduced-Order Sliding Mode

    Directory of Open Access Journals (Sweden)

    Chang Xu

    2015-11-01

    Full Text Available This paper investigates governor design by reduced-order sliding mode for a hydropower plant with an upstream surge tank. The governing system is made up of a tunnel, a surge tank, a penstock, a wicket gate and servomechanism, a governor, a hydro-turbine and a grid. Concerning the components of the governing system, their mathematic models are established. Then, these models are interconnected to simulate the governing system. From the viewpoint of state space in modern control theory, the governing system is partially observed, which challenges the governor design. By introducing an additional state variable, the control method of reduced-order sliding mode is proposed, where the governor design is based on a reduced-order governing system. Since the governor is applied to the original governing system, the system stability is analyzed by means of the small gain theorem. An genetic algorithm is employed to search a group of parameters of the predefined sliding surface, and a fuzzy inference system is utilized to decrease the chattering problem. Some numerical simulations are illustrated to verify the feasibility and robustness of the control method.

  8. Effects of Surface Coating Preparation and Sliding Modes on Titanium Oxide Coated Titanium Alloy for Aerospace Applications

    Directory of Open Access Journals (Sweden)

    Bo Yuan Peng

    2014-01-01

    electrolytic oxidation (PEO. During the PEO procedure, a composition of silicate and phosphate was used as the electrolyte. In order to evaluate the coating, pin-on-disk (POD tribology tests and cyclic inclined sliding tests were used under dry room conditions. Furthermore, scanning electron microscopy (SEM and energy dispersive spectroscopy (EDS were utilized to examine the morphology and composition of the coating surfaces. The results of the POD tests revealed that the PEO coating could have a low coefficient of friction and suggested that high silicon concentrations in the PEO coatings take away oxygen from stoichiometric Ti oxides to create lubricating oxides. In addition, cyclic inclined sliding tests showed that smaller pores on the surface of the coating could permit a higher coating cohesive strength and allow the coated Ti alloy surface to perform better under high inclined sliding forces.

  9. Finite-time convergent continuous control design based on sliding mode algorithms with application to a hydraulic drive

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2014-01-01

    -time convergence properties known from sliding control while at the same time avoiding control chattering, however, on the cost of robustness. Experimental results confirm the announced properties when applied to a hydraulic valve-cylinder drive, and demonstrates superior performance over conventional linear...

  10. A Sliding Mode LCO Regulation Strategy for Dual-Parallel Underactuated UAV Systems Using Synthetic Jet Actuators

    Directory of Open Access Journals (Sweden)

    N. Ramos-Pedroza

    2015-01-01

    careful algebraic manipulation in the regulation error system development, along with innovative design of the sliding surface. A detailed model of the UAV LCO dynamics is utilized, and a rigorous analysis is provided to prove asymptotic regulation of the pitching and plunging displacements. Numerical simulation results are provided to demonstrate the performance of the control law.

  11. Slide 1

    Indian Academy of Sciences (India)

    Slide 39 · Slide 40 · Slide 41 · Slide 42 · Confocal images of HLE3B Cells transfected with various pEGFP-recombinant constructs · LIMBAL STEM CELL CULTURE TO RESTORE VISION Clinical Trials - 500 cases · Limbal stem cell cultures · Limbal Stem Cell Cultures · Why use HAM? Limbal Stem Cell Transplantation.

  12. Vibration control of a ship engine system using high-load magnetorheological mounts associated with a new indirect fuzzy sliding mode controller

    Science.gov (United States)

    Phu, Do Xuan; Choi, Seung-Bok

    2015-02-01

    In this work, a new high-load magnetorheological (MR) fluid mount system is devised and applied to control vibration in a ship engine. In the investigation of vibration-control performance, a new modified indirect fuzzy sliding mode controller is formulated and realized. The design of the proposed MR mount is based on the flow mode of MR fluid, and it includes two separated coils for generating a magnetic field. An optimization process is carried out to achieve maximal damping force under certain design constraints, such as the allowable height of the mount. As an actuating smart fluid, a new plate-like iron-particle-based MR fluid is used, instead of the conventional spherical iron-particle-based MR fluid. After evaluating the field-dependent yield stress of the MR fluid, the field-dependent damping force required to control unwanted vibration in the ship engine is determined. Subsequently, an appropriate-sized MR mount is manufactured and its damping characteristics are evaluated. After confirming the sufficient damping force level of the manufactured MR mount, a medium-sized ship engine mount system consisting of eight MR mounts is established, and its dynamic governing equations are derived. A new modified indirect fuzzy sliding mode controller is then formulated and applied to the engine mount system. The displacement and velocity responses show that the unwanted vibrations of the ship engine system can be effectively controlled in both the axial and radial directions by applying the proposed control methodology.

  13. Sliding Mode Control of Diesel Engine Air-path System With Dual-loop EGR and VGT Based on the Reduced-order Model

    Directory of Open Access Journals (Sweden)

    Kim Sooyoung

    2016-01-01

    Full Text Available This paper presents the design of a model-based controller for the diesel engine air-path system. The controller is implemented based on a reduced order model consisting of only pressure and power dynamics with practical concerns. To deal with the model uncertainties effectively, a sliding mode controller, which is robust to model uncertainties, is proposed for the air-path system. The control performance of the proposed control scheme is verified through simulation with the valid plant model of a 6,000cc heavy duty diesel engine.

  14. Dynamical Analysis and FPGA Implementation of a Novel Hyperchaotic System and Its Synchronization Using Adaptive Sliding Mode Control and Genetically Optimized PID Control

    Directory of Open Access Journals (Sweden)

    Karthikeyan Rajagopal

    2017-01-01

    Full Text Available We announce a new 4D hyperchaotic system with four parameters. The dynamic properties of the proposed hyperchaotic system are studied in detail; the Lyapunov exponents, Kaplan-Yorke dimension, bifurcation, and bicoherence contours of the novel hyperchaotic system are derived. Furthermore, control algorithms are designed for the complete synchronization of the identical hyperchaotic systems with unknown parameters using sliding mode controllers and genetically optimized PID controllers. The stabilities of the controllers and parameter update laws are proved using Lyapunov stability theory. Use of the optimized PID controllers ensures less time of convergence and fast synchronization speed. Finally the proposed novel hyperchaotic system is realized in FPGA.

  15. Lyapunov Based-Distributed Fuzzy-Sliding Mode Control for Building Integrated-DC Microgrid with Plug-in Electric Vehicle

    DEFF Research Database (Denmark)

    Ghiasi, Mohammad Iman; Aliakbar Golkar, Masoud; Hajizadeh, Amin

    2017-01-01

    This paper presents a distributed control strategy based on Fuzzy-Sliding Mode Control (FSMC) for power control of an infrastructure integrated with a DC-Microgrid, which includes photovoltaic, fuel cell and energy storage systems with Plug-in Electric Vehicles (PEVs). In order to implement...... the proposed control strategy, first a general nonlinear modeling of a DC-Microgrid based on related DC-DC converters to each DC power sources is introduced. Secondly, a power management strategy based on fuzzy control for regulating the power flow between the hybrid DC sources, PEVs is proposed. Third...

  16. Voltage regulation of the Y-source boost DC-DC converter considering effects of leakage inductances based on cascaded sliding-mode control

    DEFF Research Database (Denmark)

    Ahmadzadeh, Soheil; Markadeh, Gholamreza Arab; Blaabjerg, Frede

    2017-01-01

    have been considered. Also, an exposition of a variable structure control approach is mentioned. The method employs cascaded slidingmode control (CSMC) to output voltage regulation of the converter. The stability and robustness of the CSMC against the variation of reference voltages......In this study, a sliding mode-based controller is designed for regulating the output voltage of a high step-up DC-DC converter with three coupled inductors called Y-source impedance network. As Y-source converter can provide a very high boost at a lower shoot-through duty cycle of the switch...

  17. A 2.1 μW/channel current-mode integrated neural recording interface

    NARCIS (Netherlands)

    Zjajo, A.; van Leuken, T.G.R.M.

    2016-01-01

    In this paper, we present a neural recording interface circuit for biomedical implantable devices, which includes low-noise signal amplification, band-pass filtering, and current-mode successive approximation A/D signal conversion. The integrated interface circuit is realized in a 65 nm CMOS

  18. Context-aware stacked convolutional neural networks for classification of breast carcinomas in whole-slide histopathology images

    NARCIS (Netherlands)

    Ehteshami Bejnordi, B.; Zuidhof, G.C.A.; Balkenhol, M.C.; Hermsen, M.; Bult, P.; Ginneken, B. van; Karssemeijer, N.; Litjens, G.J.S.; Laak, J.A.W.M. van der

    2017-01-01

    Currently, histopathological tissue examination by a pathologist represents the gold standard for breast lesion diagnostics. Automated classification of histopathological whole-slide images (WSIs) is challenging owing to the wide range of appearances of benign lesions and the visual similarity of

  19. Suppression of the noise-induced effects in an electrostatic micro-plate using an adaptive back-stepping sliding mode control.

    Science.gov (United States)

    Nwagoum Tuwa, Peguy Roussel; Woafo, P

    2017-10-19

    In this work, an adaptive backstepping sliding mode control approach is applied through the piezoelectric layer in order to control and to stabilize an electrostatic micro-plate. The mathematical model of the system by taking into account the small fluctuations in the gap considered as bounded noise is carried out. The accuracy of the proposed modal equation is proven using the method of lines. By using both approaches, the effects of noise are presented. It is found that they lead to pull-in instability as well as to random chaos. A suitable backstepping approach to improve the tracking performance is integrated to the adaptive sliding mode control in order to eliminate chattering phenomena and reinforce the robustness of the system in presence of uncertainties and external random disturbances. It is proved that all the variables of the closed-loop system are bounded and the system can follow the given reference signals as close as possible. Numerical simulations are provided to show the effectiveness of proposed controller. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  20. A New Fuzzy Sliding Mode Controller with a Disturbance Estimator for Robust Vibration Control of a Semi-Active Vehicle Suspension System

    Directory of Open Access Journals (Sweden)

    Byung-Keun Song

    2017-10-01

    Full Text Available This paper presents a new fuzzy sliding mode controller (FSMC to improve control performances in the presence of uncertainties related to model errors and external disturbance (UAD. As a first step, an adaptive control law is designed using Lyapunov stability analysis. The control law can update control parameters of the FSMC with a disturbance estimator (DE in which the closed-loop stability and finite-time convergence of tracking error are guaranteed. A solution for estimating the compensative quantity of the impact of UAD on a control system and a set of solutions are then presented in order to avoid the singular cases of the fuzzy-based function approximation, increase convergence ability, and reduce the calculating cost. Subsequently, the effectiveness of the proposed controller is verified through the investigation of vibration control performances of a semi-active vehicle suspension system featuring a magnetorheological damper (MRD. It is shown that the proposed controller can provide better control ability of vibration control with lower consumed power compared with two existing fuzzy sliding mode controllers.

  1. Dynamic modeling of a hose-drogue aerial refueling system and integral sliding mode backstepping control for the hose whipping phenomenon

    Directory of Open Access Journals (Sweden)

    Wang Haitao

    2014-08-01

    Full Text Available Dynamic modeling of a hose-drogue aerial refueling system (HDARS and an integral sliding mode backstepping controller design for the hose whipping phenomenon (HWP during probe-drogue coupling are studied. Firstly, a dynamic model of the variable-length hose-drogue assembly is built for the sake of exploiting suppression methods for the whipping phenomenon. Based on the lumped parameter method, the hose is modeled by a series of variable-length links connected with frictionless joints. A set of iterative equations of the hose’s three-dimensional motion is derived subject to hose reeling in/out, tanker motion, gravity, and aerodynamic loads accounting for the effects of steady wind, atmospheric turbulence, and tanker wake. Secondly, relying on a permanent magnet synchronous motor and high-precision position sensors, a new active control strategy for the HWP on the basis of the relative position between the tanker and the receiver is proposed. Considering the strict-feedback configuration of the permanent magnet synchronous motor, a rotor position control law based on the backstepping method is designed to insure global stability. An integral of the rotor position error and an exponential sliding mode reaching law of the current errors are applied to enhance control accuracy and robustness. Finally, the simulation results show the effectiveness of the proposed model and control laws.

  2. Optimal Switching Table-Based Sliding Mode Control of an Energy Recovery Li-Ion Power Accumulator Battery Pack Testing System

    Directory of Open Access Journals (Sweden)

    Kil To Chong

    2013-10-01

    Full Text Available The main objective of the present work is to apply a sliding mode controller (SMC to medium voltage and high power output energy recovery Li-ion power accumulator battery pack testing systems (ERLPABTSs, which are composed of a three-level neutral-point-clamped (NPC three-phase voltage source inverter (VSI and a two-level buck-boost converter without an isolating transformer. An inner current decoupled control scheme for the aforementioned system is proposed and two sliding mode planes for active and reactive current control are designed based on the control scheme. An optimized switching table for current convergence is used according to the error sign of the equivalent input voltage and feedback voltage. The proposed ERLPABTS could be used to integrate discharging energy into the power grid when performing high accuracy current testing. The active and reactive power references for the grid-connected inverter are determined based on the discharging energy from the DC-DC converter. Simulations and experiments on a laboratory hardware platform using a 175 kW insulated gate bipolar transistor (IGBT-based ERLPABTS have been implemented and verified, and the performance is found satisfactory and superior to conventional ERLPABPTS.

  3. Full-order sliding mode control of uncertain chaos in a permanent magnet synchronous motor based on a fuzzy extended state observer

    Science.gov (United States)

    Chen, Qiang; Nan, Yu-Rong; Zheng, Heng-Huo; Ren, Xue-Mei

    2015-11-01

    A full-order sliding mode control based on a fuzzy extended state observer is proposed to control the uncertain chaos in the permanent magnet synchronous motor. Through a simple coordinate transformation, the chaotic PMSM model is transformed into the Brunovsky canonical form, which is more suitable for the controller design. Based on the fuzzy control theory, a fuzzy extended state observer is developed to estimate the unknown states and uncertainties, and the restriction that all the system states should be completely measurable is avoided. Thereafter, a full-order sliding mode controller is designed to ensure the convergence of all system states without any chattering problem. Comparative simulations show the effectiveness and superior performance of the proposed control method. Project supported by the National Natural Science Foundation of China (Grant Nos. 61403343 and 61433003), the Scientific Research Foundation of Education Department of Zhejiang Province, China (Grant No. Y201329260), and the Natural Science Foundation of Zhejiang University of Technology, China (Grant No. 1301103053408).

  4. Fuzzy Sliding Mode Observer with Grey Prediction for the Estimation of the State-of-Charge of a Lithium-Ion Battery

    Directory of Open Access Journals (Sweden)

    Daehyun Kim

    2015-11-01

    Full Text Available We propose a state-of-charge (SOC estimation method for Li-ion batteries that combines a fuzzy sliding mode observer (FSMO with grey prediction. Unlike the existing methods based on a conventional first-order sliding mode observer (SMO and an adaptive gain SMO, the proposed method eliminates chattering in SOC estimation. In this method, which uses a fuzzy inference system, the gains of the SMO are adjusted according to the predicted future error and present estimation error of the terminal voltage. To forecast the future error value, a one-step-ahead terminal voltage prediction is obtained using a grey predictor. The proposed estimation method is validated through two types of discharge tests (a pulse discharge test and a random discharge test. The SOC estimation results are compared to the results of the conventional first-order SMO-based and the adaptive gain SMO-based methods. The experimental results show that the proposed method not only reduces chattering, but also improves estimation accuracy.

  5. Slide Paintings

    Science.gov (United States)

    Marshall, Sally J.

    1972-01-01

    Article describes and illustrates elementary students' paintings on 2 x 2 slides, using felt tip pens and drawing inks as well as paints to achieve experimental effects. Slides were then viewed through a projector. (PD)

  6. A fault-tolerant attitude control system for a satellite based on fuzzy global sliding mode control algorithm

    Science.gov (United States)

    Liang, Jinjin; Dong, Chaoyang; Wang, Qing

    2008-10-01

    An effective approach for fault diagnosis of aeroengine based on integration of wavelet analysis and neural networks is presented. The wavelet transform can accurately localizes the characteristics of a signal in time-frequency domains and in a view of the inter relationship of wavelet transform between exponent theory, the whole and local exponents obtained from wavelet transform coefficients as features are presented for extracting fault signals, which are inputted into radial basis function for fault pattern recognition. The fault diagnosis model of aero-engine is established and the improved Levenberg-Marquardt training algorithm is used to fulfill the network structure and parameter identification. By choosing enough samples to train the fault diagnosis network and the information representing the faults input into the neural network, the fault pattern can be determined. The robustness of wavelet neural network for fault diagnosis is discussed. The practical fault diagnosis for aeroengine vibration approves to be accurate and comprehensive.

  7. Robust Control of Industrial Hydraulic Cylinder Drives - with Special Reference to Sliding Mode- & Finite-Time Control

    DEFF Research Database (Denmark)

    Schmidt, Lasse

    extensions / modifications of first- and second order sliding controls show to be especially suitable for hydraulic cylinder drives operating under industrial conditions. These controllers demonstrate superior performance compared with conventional methods, and may be commissioned with limited tuning effort...... based gain compensator may significantly improve performance of even control systems with linear controllers. The results of compensator-plus-control designs demonstrate improved tracking performance compared to common linear control methods based on best industrial practice. In particular homogeneous......In industry, performance requirements regarding machinery, applications etc., are constantly increasing, and with the development of reliable proportional flow control components to reasonable prices, the market is increasingly turning its attention toward controllable fluid power solutions...

  8. Analog neural network control method proposed for use in a backup satellite control mode

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, J.R.; Tilden, M.W.

    1998-03-01

    The authors propose to use an analog neural network controller implemented in hardware, independent of the active control system, for use in a satellite backup control mode. The controller uses coarse sun sensor inputs. The field of view of the sensors activate the neural controller, creating an analog dead band with respect to the direction of the sun on each axis. This network controls the orientation of the vehicle toward the sunlight to ensure adequate power for the system. The attitude of the spacecraft is stabilized with respect to the ambient magnetic field on orbit. This paper develops a model of the controller using real-time coarse sun sensor data and a dynamic model of a prototype system based on a satellite system. The simulation results and the feasibility of this control method for use in a satellite backup control mode are discussed.

  9. Synchrony-induced modes of oscillation of a neural field model

    Science.gov (United States)

    Esnaola-Acebes, Jose M.; Roxin, Alex; Avitabile, Daniele; Montbrió, Ernest

    2017-11-01

    We investigate the modes of oscillation of heterogeneous ring networks of quadratic integrate-and-fire (QIF) neurons with nonlocal, space-dependent coupling. Perturbations of the equilibrium state with a particular wave number produce transient standing waves with a specific temporal frequency, analogously to those in a tense string. In the neuronal network, the equilibrium corresponds to a spatially homogeneous, asynchronous state. Perturbations of this state excite the network's oscillatory modes, which reflect the interplay of episodes of synchronous spiking with the excitatory-inhibitory spatial interactions. In the thermodynamic limit, an exact low-dimensional neural field model describing the macroscopic dynamics of the network is derived. This allows us to obtain formulas for the Turing eigenvalues of the spatially homogeneous state and hence to obtain its stability boundary. We find that the frequency of each Turing mode depends on the corresponding Fourier coefficient of the synaptic pattern of connectivity. The decay rate instead is identical for all oscillation modes as a consequence of the heterogeneity-induced desynchronization of the neurons. Finally, we numerically compute the spectrum of spatially inhomogeneous solutions branching from the Turing bifurcation, showing that similar oscillatory modes operate in neural bump states and are maintained away from onset.

  10. Fabric evolution of quartz-gouge from stable sliding to stick-slip and implications for fault slip mode

    Science.gov (United States)

    Scuderi, Marco; Collettini, Cristiano; Viti, Cecilia; Tinti, Elisa; Marone, Chris

    2017-04-01

    Numerous laboratory studies have documented the mechanisms that control the earthquake nucleation phase, when fault slip velocity is slow (1 cm/s). Although these studies are fundamental to characterize specific phases of the seismic cycle, they are not able of capturing the entire evolution of fabric and mechanical data from stable sliding to stick-slip. Here we report on laboratory experiments that illuminate the mechanisms controlling the transition from stable sliding (v= 0.001 cm/s) to dynamic stick-slip (v > 1 cm/s), by altering the elastic stiffness of the loading system (k) to match the critical rheologic stiffness of the fault gouge (kc). In particular we observe that the stiffness ratio, K = kc/k, controls the transition from slow-and-silent (K = 0.9, slip velocity 0.01 cm/s, stress drop 0.5 MPa, slip duration 0.5 s) to fast-and-audible (K = 0.5, slip velocity 3 cm/s, stress drop 2.4 MPa, slip duration 0.003 s) slip events. Microstructural observations show that with accumulated strain, deformation localizes along sharp shear planes consisting of nano-metric grains, which favour the development of frictional instabilities. Once this fabric is established, for the tested boundary conditions (normal stress 13-35 MPa), fault fabric does not change significantly with slip velocity, and fault slip behaviour is mainly controlled by the interplay between fault rheological properties and the stiffness of the loading system. As applied to tectonic faults, our results suggest that a single fault segment can experience a spectrum of fault slip behaviour depending on the evolution of fault rock frictional properties and elastic conditions of the loading system.

  11. A Robust Vibration Control of a Magnetorheological Damper Based Railway Suspension Using a Novel Adaptive Type 2 Fuzzy Sliding Mode Controller

    Directory of Open Access Journals (Sweden)

    Sy Dung Nguyen

    2017-01-01

    Full Text Available This work proposes a novel adaptive type 2 fuzzy sliding controller (AT2FC for vibration control of magnetorheological damper- (MRD- based railway suspensions subjected to uncertainty and disturbance (UAD. The AT2FC is constituted of four main parts. The first one is a sliding mode controller (SMC for specifying the main damping force supporting the suspension. This controller is designed via Lyapunov stability theory. The second one is an interpolation model based on an interval type 2 fuzzy logic system for determination of optimal parameters of the SMC. The third one is a nonlinear UAD observer to compensate for external disturbances. The fourth one is an inverse MRD model (T2F-I-MRD for specifying the input current. In the operating process, an adaptively optimal structure deriving from the SMC is created (called the Ad-op-SMC to adapt to the real status. Working as an actuator, the input current for MRD is then determined by the T2F-I-MRD to generate the required damping force which is estimated by the Ad-op-SMC and the nonlinear observer. It is shown that the obtained survey results reflect the AT2FC’s excellent vibration control performance compared with the other controllers.

  12. Roll-pitch-yaw autopilot design for nonlinear time-varying missile using partial state observer based global fast terminal sliding mode control

    Directory of Open Access Journals (Sweden)

    Awad Ahmed

    2016-10-01

    Full Text Available The acceleration autopilot design for skid-to-turn (STT missile faces a great challenge owing to coupling effect among planes, variation of missile velocity and its parameters, inexistence of a complete state vector, and nonlinear aerodynamics. Moreover, the autopilot should be designed for the entire flight envelope where fast variations exist. In this paper, a design of integrated roll-pitch-yaw autopilot based on global fast terminal sliding mode control (GFTSMC with a partial state nonlinear observer (PSNLO for STT nonlinear time-varying missile model, is employed to address these issues. GFTSMC with a novel sliding surface is proposed to nullify the integral error and the singularity problem without application of the sign function. The proposed autopilot consisting of two-loop structure, controls STT maneuver and stabilizes the rolling with a PSNLO in order to estimate the immeasurable states as an output while its inputs are missile measurable states and control signals. The missile model considers the velocity variation, gravity effect and parameters’ variation. Furthermore, the environmental conditions’ dynamics are modeled. PSNLO stability and the closed loop system stability are studied. Finally, numerical simulation is established to evaluate the proposed autopilot performance and to compare it with existing approaches in the literature.

  13. Design of Incremental Conductance Sliding Mode MPPT Control Applied by Integrated Photovoltaic and Proton Exchange Membrane Fuel Cell System under Various Operating Conditions for BLDC Motor

    Directory of Open Access Journals (Sweden)

    Jehun Hahm

    2015-01-01

    Full Text Available This paper proposes an integrated photovoltaic (PV and proton exchange membrane fuel cell (PEMFC system for continuous energy harvesting under various operating conditions for use with a brushless DC motor. The proposed scheme is based on the incremental conductance (IncCond algorithm combined with the sliding mode technique. Under changing atmospheric conditions, the energy conversion efficiency of a PV array is very low, leading to significant power losses. Consequently, increasing efficiency by means of maximum power point tracking (MPPT is particularly important. To manage such a hybrid system, control strategies need to be established to achieve the aim of the distributed system. Firstly, a Matlab/Simulink based model of the PV and PEMFC is developed and validated, as well as the incremental conductance sliding (ICS MPPT technique; then, different MPPT algorithms are employed to control the PV array under nonuniform temperature and insolation conditions, to study these algorithms effectiveness under various operating conditions. Conventional techniques are easy to implement but produce oscillations at MPP. Compared to these techniques, the proposed technique is more efficient; it produces less oscillation at MPP in the steady state and provides more precise tracking.

  14. Comparative study between PI, RST and sliding mode controllers of a DFIG supplied by an AC-AC converter for wind energy conversion system

    Directory of Open Access Journals (Sweden)

    Ahmed Bourouina

    2015-12-01

    Full Text Available This paper deals with a variable speed device to produce electrical energy on a power network, based on a doubly-fed induction generator (DFIG supplied by a direct matrix converter used in wind energy conversion systems. In the first place, we carried out briefly a study of modelling on the whole system. In order to control the power flowing between the stator of the DFIG and the power network, a control law is synthesized using three types of controllers: PI, RST and sliding mode controllers. Their respective performances are compared in terms of power reference tracking, response to sudden speed variations, sensitivity to perturbations and robustness against machine parameters variations.

  15. Sliding mode controller for four leg shunt active power filter to eliminating zero sequence current, compensating harmonics and reactive power with fixed switching frequency

    Directory of Open Access Journals (Sweden)

    Chebabhi Ali

    2015-01-01

    Full Text Available In this paper, the four leg inverter controlled by the three dimensional space vector modulation (3D SVM is used as the shunt active power filter (SAPF for compensating the three phase four wire electrical network, by using the four leg inverter with 3D SVM advantages to eliminated zero sequence current, fixed switching frequency of inverter switches, and reduced switching losses. This four leg inverter is employed as shunt active power filter to minimizing harmonic currents, reducing magnitude of neutral wire current, eliminating zero sequence current caused by nonlinear single phase loads and compensating reactive power, and a nonlinear sliding mode control technique (SMC is proposed for harmonic currents and DC bus voltage control to improve the performances of the three phase four wire four leg shunt active power filter based on Synchronous Reference Frame (SRF theory in the dq0 axes, and to decoupling the four leg SAPF mathematical model.

  16. Multi-Objective Sliding Mode Control on Vehicle Cornering Stability with Variable Gear Ratio Actuator-Based Active Front Steering Systems

    Directory of Open Access Journals (Sweden)

    Xinbo Ma

    2016-12-01

    Full Text Available Active front steering (AFS is an emerging technology to improve the vehicle cornering stability by introducing an additional small steering angle to the driver’s input. This paper proposes an AFS system with a variable gear ratio steering (VGRS actuator which is controlled by using the sliding mode control (SMC strategy to improve the cornering stability of vehicles. In the design of an AFS system, different sensors are considered to measure the vehicle state, and the mechanism of the AFS system is also modelled in detail. Moreover, in order to improve the cornering stability of vehicles, two dependent objectives, namely sideslip angle and yaw rate, are considered together in the design of SMC strategy. By evaluating the cornering performance, Sine with Dwell and accident avoidance tests are conducted, and the simulation results indicate that the proposed SMC strategy is capable of improving the cornering stability of vehicles in practice.

  17. Adaptive sliding mode back-stepping pitch angle control of a variable-displacement pump controlled pitch system for wind turbines.

    Science.gov (United States)

    Yin, Xiu-xing; Lin, Yong-gang; Li, Wei; Liu, Hong-wei; Gu, Ya-jing

    2015-09-01

    A variable-displacement pump controlled pitch system is proposed to mitigate generator power and flap-wise load fluctuations for wind turbines. The pitch system mainly consists of a variable-displacement hydraulic pump, a fixed-displacement hydraulic motor and a gear set. The hydraulic motor can be accurately regulated by controlling the pump displacement and fluid flows to change the pitch angle through the gear set. The detailed mathematical representation and dynamic characteristics of the proposed pitch system are thoroughly analyzed. An adaptive sliding mode pump displacement controller and a back-stepping stroke piston controller are designed for the proposed pitch system such that the resulting pitch angle tracks its desired value regardless of external disturbances and uncertainties. The effectiveness and control efficiency of the proposed pitch system and controllers have been verified by using realistic dataset of a 750 kW research wind turbine. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Sliding Mode Variable Structure Control and Real-Time Optimization of Dry Dual Clutch Transmission during the Vehicle’s Launch

    Directory of Open Access Journals (Sweden)

    Zhiguo Zhao

    2014-01-01

    Full Text Available In order to reflect driving intention adequately and improve the launch performance of vehicle equipped with five-speed dry dual clutch transmission (DCT, the issue of coordinating control between engine and clutch is researched, which is based on the DCT and prototype car developed independently. Four-degree-of-freedom (DOF launch dynamics equations are established. Taking advantage of predictive control and genetic algorithm, target tracing curves of engine speed and vehicle velocity are optimally specified. Sliding mode variable structure (SMVS control strategy is designed to track these curves. The rapid prototyping experiment and test are, respectively, conducted on the DCT test bench and in the chassis dynamometer. Results show that the designed SMVS control strategy not only effectively embodies the driver’s intention but also has strong robustness to the vehicle parameter’s variations.

  19. Sliding Controller of Switched Reluctance Motor

    Directory of Open Access Journals (Sweden)

    Abdel Ghani AISSAOUI

    2008-06-01

    Full Text Available This paper presents an application of sliding mode control for switched reluctance motor (SRM speed. The sliding mode technique finds its stronger justification in the utilization of a robust control law to model uncertainties. A sliding mode controller of the motor speed is then designed and simulated. Digital simulation results shows that the designed sliding speed controller realises a good dynamic behaviour of the motor, a perfect speed tracking with no overshoot and a good rejection of impact loads disturbance. The results of applying the sliding mode controller to a SRM give best performances and high robustness than those obtained by the application of a conventional controller (PI.

  20. Day-Ahead Natural Gas Demand Forecasting Using Optimized ABC-Based Neural Network with Sliding Window Technique: The Case Study of Regional Basis in Turkey

    Directory of Open Access Journals (Sweden)

    Mustafa Akpinar

    2017-06-01

    Full Text Available The increase of energy consumption in the world is reflected in the consumption of natural gas. However, this increment requires additional investment. This effect leads imbalances in terms of demand forecasting, such as applying penalties in the case of error rates occurring beyond the acceptable limits. As the forecasting errors increase, penalties increase exponentially. Therefore, the optimal use of natural gas as a scarce resource is important. There are various demand forecast ranges for natural gas and the most difficult range among these demands is the day-ahead forecasting, since it is hard to implement and makes predictions with low error rates. The objective of this study is stabilizing gas tractions on day-ahead demand forecasting using low-consuming subscriber data for minimizing error using univariate artificial bee colony-based artificial neural networks (ANN-ABC. For this purpose, households and low-consuming commercial users’ four-year consumption data between the years of 2011–2014 are gathered in daily periods. Previous consumption values are used to forecast day-ahead consumption values with sliding window technique and other independent variables are not taken into account. Dataset is divided into two parts. First, three-year daily consumption values are used with a seven day window for training the networks, while the last year is used for the day-ahead demand forecasting. Results show that ANN-ABC is a strong, stable, and effective method with a low error rate of 14.9 mean absolute percentage error (MAPE for training utilizing MAPE with a univariate sliding window technique.

  1. Sunspots Time-Series Prediction Based on Complementary Ensemble Empirical Mode Decomposition and Wavelet Neural Network

    Directory of Open Access Journals (Sweden)

    Guohui Li

    2017-01-01

    Full Text Available The sunspot numbers are the major target which describes the solar activity level. Long-term prediction of sunspot activity is of great importance for aerospace, communication, disaster prevention, and so on. To improve the prediction accuracy of sunspot time series, the prediction model based on complementary ensemble empirical mode decomposition (CEEMD and wavelet neural network (WNN is proposed. First, the sunspot time series are decomposed by CEEMD to obtain a set of intrinsic modal functions (IMFs. Then, the IMFs and residuals are reconstructed to obtain the training samples and the prediction samples, and these samples are trained and predicted by WNN. Finally, the reconstructed IMFs and residuals are the final prediction results. Five kinds of prediction models are compared, which are BP neural network prediction model, WNN prediction model, empirical mode decomposition and WNN hybrid prediction model, ensemble empirical mode decomposition and WNN hybrid prediction model, and the proposed method in this paper. The same sunspot time series are predicted with five kinds of prediction models. The experimental results show that the proposed model has better prediction accuracy and smaller error.

  2. Synchronization of nonidentical chaotic neural networks with leakage delay and mixed time-varying delays

    Directory of Open Access Journals (Sweden)

    Cao Jinde

    2011-01-01

    Full Text Available Abstract In this paper, an integral sliding mode control approach is presented to investigate synchronization of nonidentical chaotic neural networks with discrete and distributed time-varying delays as well as leakage delay. By considering a proper sliding surface and constructing Lyapunov-Krasovskii functional, as well as employing a combination of the free-weighting matrix method, Newton-Leibniz formulation and inequality technique, a sliding mode controller is designed to achieve the asymptotical synchronization of the addressed nonidentical neural networks. Moreover, a sliding mode control law is also synthesized to guarantee the reachability of the specified sliding surface. The provided conditions are expressed in terms of linear matrix inequalities, and are dependent on the discrete and distributed time delays as well as leakage delay. A simulation example is given to verify the theoretical results.

  3. Extracting spatial-temporal coherent patterns in large-scale neural recordings using dynamic mode decomposition.

    Science.gov (United States)

    Brunton, Bingni W; Johnson, Lise A; Ojemann, Jeffrey G; Kutz, J Nathan

    2016-01-30

    There is a broad need in neuroscience to understand and visualize large-scale recordings of neural activity, big data acquired by tens or hundreds of electrodes recording dynamic brain activity over minutes to hours. Such datasets are characterized by coherent patterns across both space and time, yet existing computational methods are typically restricted to analysis either in space or in time separately. Here we report the adaptation of dynamic mode decomposition (DMD), an algorithm originally developed for studying fluid physics, to large-scale neural recordings. DMD is a modal decomposition algorithm that describes high-dimensional dynamic data using coupled spatial-temporal modes. The algorithm is robust to variations in noise and subsampling rate; it scales easily to very large numbers of simultaneously acquired measurements. We first validate the DMD approach on sub-dural electrode array recordings from human subjects performing a known motor task. Next, we combine DMD with unsupervised clustering, developing a novel method to extract spindle networks during sleep. We uncovered several distinct sleep spindle networks identifiable by their stereotypical cortical distribution patterns, frequency, and duration. DMD is closely related to principal components analysis (PCA) and discrete Fourier transform (DFT). We may think of DMD as a rotation of the low-dimensional PCA space such that each basis vector has coherent dynamics. The resulting analysis combines key features of performing PCA in space and power spectral analysis in time, making it particularly suitable for analyzing large-scale neural recordings. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Decentralized adaptive robust control based on sliding mode and nonlinear compensator for the control of ankle movement using functional electrical stimulation of agonist-antagonist muscles

    Science.gov (United States)

    Kobravi, Hamid-Reza; Erfanian, Abbas

    2009-08-01

    A decentralized control methodology is designed for the control of ankle dorsiflexion and plantarflexion in paraplegic subjects with electrical stimulation of tibialis anterior and calf muscles. Each muscle joint is considered as a subsystem and individual controllers are designed for each subsystem. Each controller operates solely on its associated subsystem, with no exchange of information between the subsystems. The interactions between the subsystems are taken as external disturbances for each isolated subsystem. In order to achieve robustness with respect to external disturbances, unmodeled dynamics, model uncertainty and time-varying properties of muscle-joint dynamics, a robust control framework is proposed which is based on the synergistic combination of an adaptive nonlinear compensator with a sliding mode control and is referred to as an adaptive robust control. Extensive simulations and experiments on healthy and paraplegic subjects were performed to demonstrate the robustness against the time-varying properties of muscle-joint dynamics, day-to-day variations, subject-to-subject variations, fast convergence, stability and tracking accuracy of the proposed method. The results indicate that the decentralized robust control provides excellent tracking control for different reference trajectories and can generate control signals to compensate the muscle fatigue and reject the external disturbance. Moreover, the controller is able to automatically regulate the interaction between agonist and antagonist muscles under different conditions of operating without any preprogrammed antagonist activities.

  5. CASPIAN SEA LEVEL PREDICTION USING ARTIFICIAL NEURAL NETWORK AND EMPIRICAL MODE DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    Nikolai Makarenko

    2010-01-01

    Full Text Available This paper demonstrates the possibility of using nonlinear modeling for prediction of the Caspian Sea level. Phase space geometry of the of a model can be reconstructed by the embedology methods. Dynamical invariants, such as the Lyapunov exponents, the Kaplan-Yorke dimension, and the prediction horizon were estimated from reconstruction. Fractal and multifractal analyses were carried out for various time intervals of the Caspian Sea level and multifractal spectra were calculated. Then, historical data resolution was improved with the help of fractal approximation. The EMD method was used to reduce noise of the time series. Global nonlinear predictions were made with the help of Artificial Neural Network for combinations of different empirical modes.

  6. Stability analysis of switched cellular neural networks: A mode-dependent average dwell time approach.

    Science.gov (United States)

    Huang, Chuangxia; Cao, Jie; Cao, Jinde

    2016-10-01

    This paper addresses the exponential stability of switched cellular neural networks by using the mode-dependent average dwell time (MDADT) approach. This method is quite different from the traditional average dwell time (ADT) method in permitting each subsystem to have its own average dwell time. Detailed investigations have been carried out for two cases. One is that all subsystems are stable and the other is that stable subsystems coexist with unstable subsystems. By employing Lyapunov functionals, linear matrix inequalities (LMIs), Jessen-type inequality, Wirtinger-based inequality, reciprocally convex approach, we derived some novel and less conservative conditions on exponential stability of the networks. Comparing to ADT, the proposed MDADT show that the minimal dwell time of each subsystem is smaller and the switched system stabilizes faster. The obtained results extend and improve some existing ones. Moreover, the validness and effectiveness of these results are demonstrated through numerical simulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Slide 1

    Indian Academy of Sciences (India)

    Table of contents. Slide 1 · NATIONAL JALMA INSTITUTE FOR LEPROSY & OTHER MYCOBACTERIAL DISEASES : MAJOR THRUST AREAS · NJILOMD : THRUST AREAS · Model Rural Health Research Unit Ghatampur ( Kanpur) · Current scenario · Prevalence of drug resistance · Initial drug resistance in India : static or ...

  8. Slide 1

    Indian Academy of Sciences (India)

    Communications · Milestones in Communications · Internet · Speed · Broadband Access · Digital Subscriber Line (DSL) · Wireless Access · DSL · DMT DSL · Slide 11 · Lets Focus on Upstream (US) · Upstream Mathematical Model – tone wise · Crosstalk Characteristics · Performance loss due to FEXT * · Research Issues in ...

  9. A decentralized modular control framework for robust control of FES-activated walker-assisted paraplegic walking using terminal sliding mode and fuzzy logic control.

    Science.gov (United States)

    Nekoukar, Vahab; Erfanian, Abbas

    2012-10-01

    A major challenge to developing functional electrical stimulation (FES) systems for paraplegic walking and widespread acceptance of these systems is the design of a robust control strategy that provides satisfactory tracking performance. The systems need to be robust against time-varying properties of neuromusculoskeletal dynamics, day-to-day variations, subject-to-subject variations, external disturbances, and must be easily applied without requiring offline identification during different experimental sessions. Another major problem related to walker-assisted FES-activated walking concerns the high metabolic rate and upper body effort that limit the clinical applications of FES systems. In this paper, we present a novel decentralized modular control framework for robust control of walker-assisted FES-activated walking. For each muscle-joint dynamics, an independent module control is designed, and the dynamics of the plant are identified online. This process requires no prior knowledge about the dynamics of the plant to be controlled and no offline learning phase. The module is based on adaptive fuzzy terminal sliding mode control and fuzzy logic control. The module control adjusts both pulse-amplitude and pulsewidth of the stimulation signal in such a way that upper body effort is minimized and the lower extremity walking pattern lies within a defined boundary of the reference trajectory. The proposed control strategy has been evaluated on three paraplegic subjects. The results showed that accurate tracking performance and smooth walking pattern were achieved. This favorable performance was obtained without requiring offline identification, manual adjustments, and predefined ON/OFF timing of the muscles.

  10. A magnetorheological damper-based prosthetic knee (MRPK) and sliding mode tracking control method for an MRPK-based lower limb prosthesis

    Science.gov (United States)

    Fu, Qiang; Wang, Dai-Hua; Xu, Lei; Yuan, Gang

    2017-04-01

    Based on a two-bar linkage and a magnetorheological damper (MRD) with a double-ended structure and shearing operation mode of the magnetorheological fluid, an MRD-based prosthetic knee (MRPK) is realized. Utilizing the developed MRPK, an MRD-based lower limb prosthesis (MRLLP) is developed, modeled, and simulated in this paper, to analyse the effects of hysteresis of the integrated MRD on the swing angle of the shank of the MRLLP. Based on this, a sliding mode tracking control (SMTC) method for controlling the swing angle of the shank of the MRLLP is proposed to suppress hysteresis, along with a robustness analysis. Utilizing the SMTC method, co-simulations on controlling the swing angle of the shank of the MRLLP are carried out in ADAMS and Simulink. The simulation results show that the root mean square error (RMSE) of the swing angle of the shank of the MRLLP produced by the SMTC method is 80% less than that from the computed torque plus PD (CT+PD) control method. Therefore, the SMTC method is effective in suppressing hysteresis of the MRD. Furthermore, when the MRLLP is disturbed, the RMSE of the swing angle of the shank of the MRLLP produced by the SMTC method is 67% less than that from the CT+PD control method. Therefore, the SMTC method has strong robustness to random disturbance. A rapid control prototype of the MRLLP system and a corresponding experimental test system are established. On the established experimental test system, experiments are carried out on control of the swing angle of the shank of the MRLLP via the SMTC method. The results are compared with those from the ON/OFF and the CT+PD control methods. The experimental results show that the MRPK has controllable joint torque, and can be used to imitate the natural swing of a human knee joint. Additionally, the RMSE of the controlled swing angle of the shank of the MRLLP produced by the SMTC method is 34% less than that produced by the CT+PD control method and is 37% less than that from the ON

  11. Travel Mode Detection Based on Neural Networks and Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Guangnian Xiao

    2015-08-01

    Full Text Available The collection of massive Global Positioning System (GPS data from travel surveys has increased exponentially worldwide since the 1990s. A number of methods, which range from rule-based to advanced classification approaches, have been applied to detect travel modes from GPS positioning data collected in travel surveys based on GPS-enabled smartphones or dedicated GPS devices. Among these approaches, neural networks (NNs are widely adopted because they can extract subtle information from training data that cannot be directly obtained by human or other analysis techniques. However, traditional NNs, which are generally trained by back-propagation algorithms, are likely to be trapped in local optimum. Therefore, particle swarm optimization (PSO is introduced to train the NNs. The resulting PSO-NNs are employed to distinguish among four travel modes (walk, bike, bus, and car with GPS positioning data collected through a smartphone-based travel survey. As a result, 95.81% of samples are correctly flagged for the training set, while 94.44% are correctly identified for the test set. Results from this study indicate that smartphone-based travel surveys provide an opportunity to supplement traditional travel surveys.

  12. Wrestling model of the repertoire of activity propagation modes in quadruple neural networks.

    Science.gov (United States)

    Shteingart, Hanan; Raichman, Nadav; Baruchi, Itay; Ben-Jacob, Eshel

    2010-01-01

    The spontaneous activity of engineered quadruple cultured neural networks (of four-coupled sub-networks) exhibits a repertoire of different types of mutual synchronization events. Each event corresponds to a specific activity propagation mode (APM) defined by the order of activity propagation between the sub-networks. We statistically characterized the frequency of spontaneous appearance of the different types of APMs. The relative frequencies of the APMs were then examined for their power-law properties. We found that the frequencies of appearance of the leading (most frequent) APMs have close to constant algebraic ratio reminiscent of Zipf's scaling of words. We show that the observations are consistent with a simplified "wrestling" model. This model represents an extension of the "boxing arena" model which was previously proposed to describe the ratio between the two activity modes in two coupled sub-networks. The additional new element in the "wrestling" model presented here is that the firing within each network is modeled by a time interval generator with similar intra-network Lévy distribution. We modeled the different burst-initiation zones' interaction by competition between the stochastic generators with Gaussian inter-network variability. Estimation of the model parameters revealed similarity across different cultures while the inter-burst-interval of the cultures was similar across different APMs as numerical simulation of the model predicts.

  13. Forecasting outpatient visits using empirical mode decomposition coupled with back-propagation artificial neural networks optimized by particle swarm optimization.

    Science.gov (United States)

    Huang, Daizheng; Wu, Zhihui

    2017-01-01

    Accurately predicting the trend of outpatient visits by mathematical modeling can help policy makers manage hospitals effectively, reasonably organize schedules for human resources and finances, and appropriately distribute hospital material resources. In this study, a hybrid method based on empirical mode decomposition and back-propagation artificial neural networks optimized by particle swarm optimization is developed to forecast outpatient visits on the basis of monthly numbers. The data outpatient visits are retrieved from January 2005 to December 2013 and first obtained as the original time series. Second, the original time series is decomposed into a finite and often small number of intrinsic mode functions by the empirical mode decomposition technique. Third, a three-layer back-propagation artificial neural network is constructed to forecast each intrinsic mode functions. To improve network performance and avoid falling into a local minimum, particle swarm optimization is employed to optimize the weights and thresholds of back-propagation artificial neural networks. Finally, the superposition of forecasting results of the intrinsic mode functions is regarded as the ultimate forecasting value. Simulation indicates that the proposed method attains a better performance index than the other four methods.

  14. Use of Time-Frequency Analysis and Neural Networks for Mode Identification in a Wireless Software-Defined Radio Approach

    Directory of Open Access Journals (Sweden)

    Matteo Gandetto

    2004-09-01

    Full Text Available The use of time-frequency distributions is proposed as a nonlinear signal processing technique that is combined with a pattern recognition approach to identify superimposed transmission modes in a reconfigurable wireless terminal based on software-defined radio techniques. In particular, a software-defined radio receiver is described aiming at the identification of two coexistent communication modes: frequency hopping code division multiple access and direct sequence code division multiple access. As a case study, two standards, based on the previous modes and operating in the same band (industrial, scientific, and medical, are considered: IEEE WLAN 802.11b (direct sequence and Bluetooth (frequency hopping. Neural classifiers are used to obtain identification results. A comparison between two different neural classifiers is made in terms of relative error frequency.

  15. Mixed Mode Oscillations and Synchronous Activity in Noise Induced Modified Morris-Lecar Neural System

    Science.gov (United States)

    Upadhyay, Ranjit Kumar; Mondal, Argha; Teka, Wondimu W.

    The modified three-dimensional (3D) Morris-Lecar (M-L) model is very useful to understand the spiking activities of neurons. The present article addresses the random dynamical behavior of a modified M-L model driven by a white Gaussian noise with mean zero and unit spectral density. The applied stimulus can be expressed as a random term. Such random perturbations are represented by a white Gaussian noise current added through the electrical potential of membrane of the excitatory principal cells. The properties of the stochastic system (perturbed one) and noise induced mixed mode oscillation are analyzed. The Lyapunov spectrum is computed to present the nature of the system dynamics. The noise intensity is varied while keeping fixed the predominant parameters of the model in their ranges and also observed the changes in the dynamical behavior of the system. The dynamical synchronization is studied in the coupled M-L systems interconnected by excitatory and inhibitory neurons with noisy electrical coupling and verified with similarity functions. This result suggests the potential benefits of noise and noise induced oscillations which have been observed in real neurons and how that affects the dynamics of the neural model as well as the coupled systems. The analysis reports that the modified M-L system which has the limit cycle behavior can show a type of phase locking behavior which follows either period adding (i.e. 1:1, 2:1, 3:1, 4:1) sequences or Farey sequences. For the coupled neural systems, complete synchronization is shown for sufficient noisy coupling strength.

  16. Empirical mode decomposition and neural networks on FPGA for fault diagnosis in induction motors.

    Science.gov (United States)

    Camarena-Martinez, David; Valtierra-Rodriguez, Martin; Garcia-Perez, Arturo; Osornio-Rios, Roque Alfredo; Romero-Troncoso, Rene de Jesus

    2014-01-01

    Nowadays, many industrial applications require online systems that combine several processing techniques in order to offer solutions to complex problems as the case of detection and classification of multiple faults in induction motors. In this work, a novel digital structure to implement the empirical mode decomposition (EMD) for processing nonstationary and nonlinear signals using the full spline-cubic function is presented; besides, it is combined with an adaptive linear network (ADALINE)-based frequency estimator and a feed forward neural network (FFNN)-based classifier to provide an intelligent methodology for the automatic diagnosis during the startup transient of motor faults such as: one and two broken rotor bars, bearing defects, and unbalance. Moreover, the overall methodology implementation into a field-programmable gate array (FPGA) allows an online and real-time operation, thanks to its parallelism and high-performance capabilities as a system-on-a-chip (SoC) solution. The detection and classification results show the effectiveness of the proposed fused techniques; besides, the high precision and minimum resource usage of the developed digital structures make them a suitable and low-cost solution for this and many other industrial applications.

  17. Empirical Mode Decomposition and Neural Networks on FPGA for Fault Diagnosis in Induction Motors

    Directory of Open Access Journals (Sweden)

    David Camarena-Martinez

    2014-01-01

    Full Text Available Nowadays, many industrial applications require online systems that combine several processing techniques in order to offer solutions to complex problems as the case of detection and classification of multiple faults in induction motors. In this work, a novel digital structure to implement the empirical mode decomposition (EMD for processing nonstationary and nonlinear signals using the full spline-cubic function is presented; besides, it is combined with an adaptive linear network (ADALINE-based frequency estimator and a feed forward neural network (FFNN-based classifier to provide an intelligent methodology for the automatic diagnosis during the startup transient of motor faults such as: one and two broken rotor bars, bearing defects, and unbalance. Moreover, the overall methodology implementation into a field-programmable gate array (FPGA allows an online and real-time operation, thanks to its parallelism and high-performance capabilities as a system-on-a-chip (SoC solution. The detection and classification results show the effectiveness of the proposed fused techniques; besides, the high precision and minimum resource usage of the developed digital structures make them a suitable and low-cost solution for this and many other industrial applications.

  18. Principal dynamic mode analysis of neural mass model for the identification of epileptic states

    Science.gov (United States)

    Cao, Yuzhen; Jin, Liu; Su, Fei; Wang, Jiang; Deng, Bin

    2016-11-01

    The detection of epileptic seizures in Electroencephalography (EEG) signals is significant for the diagnosis and treatment of epilepsy. In this paper, in order to obtain characteristics of various epileptiform EEGs that may differentiate different states of epilepsy, the concept of Principal Dynamic Modes (PDMs) was incorporated to an autoregressive model framework. First, the neural mass model was used to simulate the required intracerebral EEG signals of various epileptiform activities. Then, the PDMs estimated from the nonlinear autoregressive Volterra models, as well as the corresponding Associated Nonlinear Functions (ANFs), were used for the modeling of epileptic EEGs. The efficient PDM modeling approach provided physiological interpretation of the system. Results revealed that the ANFs of the 1st and 2nd PDMs for the auto-regressive input exhibited evident differences among different states of epilepsy, where the ANFs of the sustained spikes' activity encountered at seizure onset or during a seizure were the most differentiable from that of the normal state. Therefore, the ANFs may be characteristics for the classification of normal and seizure states in the clinical detection of seizures and thus provide assistance for the diagnosis of epilepsy.

  19. Multivariable robust adaptive sliding mode control of an industrial boiler-turbine in the presence of modeling imprecisions and external disturbances: A comparison with type-I servo controller.

    Science.gov (United States)

    Ghabraei, Soheil; Moradi, Hamed; Vossoughi, Gholamreza

    2015-09-01

    To guarantee the safety and efficient performance of the power plant, a robust controller for the boiler-turbine unit is needed. In this paper, a robust adaptive sliding mode controller (RASMC) is proposed to control a nonlinear multi-input multi-output (MIMO) model of industrial boiler-turbine unit, in the presence of unknown bounded uncertainties and external disturbances. To overcome the coupled nonlinearities and investigate the zero dynamics, input-output linearization is performed, and then the new decoupled inputs are derived. To tackle the uncertainties and external disturbances, appropriate adaption laws are introduced. For constructing the RASMC, suitable sliding surface is considered. To guarantee the sliding motion occurrence, appropriate control laws are constructed. Then the robustness and stability of the proposed RASMC is proved via Lyapunov stability theory. To compare the performance of the purposed RASMC with traditional control schemes, a type-I servo controller is designed. To evaluate the performance of the proposed control schemes, simulation studies on nonlinear MIMO dynamic system in the presence of high frequency bounded uncertainties and external disturbances are conducted and compared. Comparison of the results reveals the superiority of proposed RASMC over the traditional control schemes. RAMSC acts efficiently in disturbance rejection and keeping the system behavior in desirable tracking objectives, without the existence of unstable quasi-periodic solutions. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  20. Contribution to the Artifical Neural Network Speed Estimator in a Degraded Mode for Sensor-Less Fuzzy Direct Control of Torque Application Using Dual Stars Induction Machine

    National Research Council Canada - National Science Library

    Hechelef Mohammed; Abdelkader Meroufel

    2015-01-01

    ... network accordingly, both strategies can manage the degraded and normal modes. The neural networks used are the back-propagation, to reduce the training patterns and increase the execution speed of the training...