Multivariable robust PID control for a PEMFC system
Energy Technology Data Exchange (ETDEWEB)
Wang, Fu-Cheng; Ko, Chin-Chun [Department of Mechanical Engineering, National Taiwan University, No. 1 Roosevelt Rd. Sec. 4, Taipei 10617 (China)
2010-10-15
This paper proposes robust proportional-integral-derivative (PID) control for a proton exchange membrane fuel cell (PEMFC) system. We model a PEMFC as a multivariable system, and apply identification techniques to obtain the system's transfer function matrices, where system variations and disturbances are regarded as uncertainties. Because robust control can cope with system uncertainties and disturbances, it has been successfully applied to improve the stability, performance, and efficiency of PEMFC systems in previous studies. However, the resulting robust controllers might be too complicated for hardware implementation. On the other hand, PID control has been widely applicable to engineering practices because of its simple structure, but it lacks stability analysis for systems with uncertainties. Therefore, by combining the merits of robust control and PID control, we design robust PID controllers for the PEMFC system. Based on evaluation of stability, performance, and efficiencies, the proposed robust PID controllers are shown to be effective. (author)
PID control with robust disturbance feedback control
DEFF Research Database (Denmark)
Kawai, Fukiko; Vinther, Kasper; Andersen, Palle
2015-01-01
Disturbance Feedback Control (DFC) is a technique, originally proposed by Fuji Electric, for augmenting existing control systems with an extra feedback for attenuation of disturbances and model errors. In this work, we analyze the robustness and performance of a PID-based control system with DFC...... and performance (if such gains exist). Finally, two different simulation case studies are evaluated and compared. Our numerical studies indicate that better performance can be achieved with the proposed method compared with a conservatively tuned PID controller and comparable performance can be achieved when...... compared with an H-infinity controller....
Recurrent neural networks-based multivariable system PID predictive control
Institute of Scientific and Technical Information of China (English)
ZHANG Yan; WANG Fanzhen; SONG Ying; CHEN Zengqiang; YUAN Zhuzhi
2007-01-01
A nonlinear proportion integration differentiation (PID) controller is proposed on the basis of recurrent neural networks,due to the difficulty of tuning the parameters of conventional PID controller.In the control process of nonlinear multivariable system,a decoupling controller was constructed,which took advantage of multi-nonlinear PID controllers in parallel.With the idea of predictive control,two multivariable predictive control strategies were established.One strategy involved the use of the general minimum variance control function on the basis of recursive multi-step predictive method.The other involved the adoption of multistep predictive cost energy to train the weights of the decoupling controller.Simulation studies have shown the efficiency of these strategies.
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Xiaoli Luan
2016-01-01
Full Text Available The aim of this paper is to determine the stabilizing PID parametric region for multivariable systems. Firstly, a general equivalent transfer function parameterization method is proposed to construct the multiloop equivalent process for multivariable systems. Then, based on the equivalent single loops, a model-based method is presented to derive the stabilizing PID parametric region by using the generalized Hermite-Biehler theorem. By sweeping over the entire ranges of feasible proportional gains and determining the stabilizing regions in the space of integral and derivative gains, the complete set of stabilizing PID controllers can be determined. The robustness of the design procedure against the approximation in getting the SISO plants is analyzed. Finally, simulation of a practical model is carried out to illustrate the effectiveness of the proposed technique.
Computation of robustly stabilizing PID controllers for interval systems.
Matušů, Radek; Prokop, Roman
2016-01-01
The paper is focused on the computation of all possible robustly stabilizing Proportional-Integral-Derivative (PID) controllers for plants with interval uncertainty. The main idea of the proposed method is based on Tan's (et al.) technique for calculation of (nominally) stabilizing PI and PID controllers or robustly stabilizing PI controllers by means of plotting the stability boundary locus in either P-I plane or P-I-D space. Refinement of the existing method by consideration of 16 segment plants instead of 16 Kharitonov plants provides an elegant and efficient tool for finding all robustly stabilizing PID controllers for an interval system. The validity and relatively effortless application of presented theoretical concepts are demonstrated through a computation and simulation example in which the uncertain mathematical model of an experimental oblique wing aircraft is robustly stabilized.
Genetic Algorithm Optimisation of PID Controllers for a Multivariable Process
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Wael Alharbi
2017-03-01
Full Text Available This project is about the design of PID controllers and the improvement of outputs in multivariable processes. The optimisation of PID controller for the Shell oil process is presented in this paper, using Genetic Algorithms (GAs. Genetic Algorithms (GAs are used to automatically tune PID controllers according to given specifications. They use an objective function, which is specially formulated and measures the performance of controller in terms of time-domain bounds on the responses of closed-loop process.A specific objective function is suggested that allows the designer for a single-input, single-output (SISO process to explicitly specify the process performance specifications associated with the given problem in terms of time-domain bounds, then experimentally evaluate the closed-loop responses. This is investigated using a simple two-term parametric PID controller tuning problem. The results are then analysed and compared with those obtained using a number of popular conventional controller tuning methods. The intention is to demonstrate that the proposed objective function is inherently capable of accurately quantifying complex performance specifications in the time domain. This is something that cannot normally be employed in conventional controller design or tuning methods.Finally, the recommended objective function will be used to examine the control problems of Multi-Input-Multi-Output (MIMO processes, and the results will be presented in order to determine the efficiency of the suggested control system.
Singularly Perturbation Method Applied To Multivariable PID Controller Design
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Mashitah Che Razali
2015-01-01
Full Text Available Proportional integral derivative (PID controllers are commonly used in process industries due to their simple structure and high reliability. Efficient tuning is one of the relevant issues of PID controller type. The tuning process always becomes a challenging matter especially for multivariable system and to obtain the best control tuning for different time scales system. This motivates the use of singularly perturbation method into the multivariable PID (MPID controller designs. In this work, wastewater treatment plant and Newell and Lee evaporator were considered as system case studies. Four MPID control strategies, Davison, Penttinen-Koivo, Maciejowski, and Combined methods, were applied into the systems. The singularly perturbation method based on Naidu and Jian Niu algorithms was applied into MPID control design. It was found that the singularly perturbed system obtained by Naidu method was able to maintain the system characteristic and hence was applied into the design of MPID controllers. The closed loop performance and process interactions were analyzed. It is observed that less computation time is required for singularly perturbed MPID controller compared to the conventional MPID controller. The closed loop performance shows good transient responses, low steady state error, and less process interaction when using singularly perturbed MPID controller.
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Sivananaithaperumal Sudalaiandi
2014-06-01
Full Text Available This paper presents an automatic tuning of multivariable Fractional-Order Proportional, Integral and Derivative controller (FO-PID parameters using Covariance Matrix Adaptation Evolution Strategy (CMAES algorithm. Decoupled multivariable FO-PI and FO-PID controller structures are considered. Oustaloup integer order approximation is used for the fractional integrals and derivatives. For validation, two Multi-Input Multi- Output (MIMO distillation columns described byWood and Berry and Ogunnaike and Ray are considered for the design of multivariable FO-PID controller. Optimal FO-PID controller is designed by minimizing Integral Absolute Error (IAE as objective function. The results of previously reported PI/PID controller are considered for comparison purposes. Simulation results reveal that the performance of FOPI and FO-PID controller is better than integer order PI/PID controller in terms of IAE. Also, CMAES algorithm is suitable for the design of FO-PI / FO-PID controller.
IMC based robust PID controller tuning for disturbance rejection
Institute of Scientific and Technical Information of China (English)
Mohammad Shamsuzzoha
2016-01-01
It is well-known that the IMC-PID controller tuning gives fast and improved set point response but slow disturbance rejection. A modification has been proposed in IMC-PID tuning rule for the improved disturbance rejection. For the modified IMC-PID tuning rule, a method has been developed to obtain the IMC-PID setting in closed-loop mode without acquiring detailed information of the process. The proposed method is based on the closed-loop step set point experiment using a proportional only controller with gainKc0. It is the direct approach to find the PID controller setting similar to classical Ziegler-Nichols closed-loop method. Based on simulations of a wide range of first-order with delay processes, a simple correlation has been derived to obtain the modified IMC-PID controller settings from closed-loop experiment. In this method, controller gain is a function of the overshoot obtained in the closed loop set point experiment. The integral and derivative time is mainly a function of the time to reach the first peak (overshoot). Simulation has been conducted for the broad class of processes and the controllers were tuned to have the same degree of robustness by measuring the maximum sensitivity, Ms, in order to obtain a reasonable comparison. The PID controller settings obtained in the proposed tuning method show better performance and robustness with other two-step tuning methods for the broad class of processes. It has also been applied to temperature control loop in distillation column model. The result has been compared to the open loop tuning method where it gives robust and fast response.
A toolbox for robust PID controller tuning using convex optimization
Sadeghpour, Mehdi; de Oliveira, Vinicius; Karimi, Alireza
2012-01-01
A robust PID controller design toolbox for Matlab is presented in this paper. The design is based on linearizing or convexifying the conventional non-convex constraints on the classical robustness margins or H∞ constraints. Then the existing optimization solvers can be used to compute the controller parameters. The software can be used in a wide range of controller design problems, including multi-model systems and gain-scheduled controllers. The models can be parametric or non-parametric whi...
Robust Stability and Performance Comparison of PID and PPI Control
Institute of Scientific and Technical Information of China (English)
任正云; 张红; 邵惠鹤
2004-01-01
Predictive PI (PPI) control form, capable of time delay compensation, has been put forward recently. This control algorithm is essentially a PI controller with enhanced derivative action, which is not only suitable for long time delay process, but also of simple structure and excellent robust stability. The performance of PPI controller was demonstrated and compared with that of traditional PID controller by different tuning methods.
Model-reference robust tuning of PID controllers
Alfaro, Victor M
2016-01-01
This book presents a unified methodology for the design of PID controllers that encompasses the wide range of different dynamics to be found in industrial processes. This is extended to provide a coherent way of dealing with the tuning of PID controllers. The particular method at the core of the book is the so-called model-reference robust tuning (MoReRT), developed by the authors. MoReRT constitutes a novel and powerful way of thinking of a robust design and taking into account the usual design trade-offs encountered in any control design problem. The book starts by presenting the different two-degree-of-freedom PID control algorithm variations and their conversion relations as well as the indexes used for performance, robustness and fragility evaluation:the bases of the proposed model. Secondly, the MoReRT design methodology and normalized controlled process models and controllers used in the design are described in order to facilitate the formulation of the different design problems and subsequent derivati...
An Implementation Technique for Multivariate Robust Design
Institute of Scientific and Technical Information of China (English)
MA Yi-zhong; ZHAO Feng-yu
2005-01-01
This paper investigates systematically the problem of multivariate robust parameter design. First, a measurement criterion for the total variation of multivariate quality characteristics is introduced by the result of information theory. Then the implementation procedure in the robust design is presented. After that, a simulation example from a practical industrial process is provided. Finally, some comments and further work are discussed.
ROBUST INTERNAL MODEL CONTROL STRATEGY BASED PID CONTROLLER FOR BLDCM
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A.PURNA CHANDRA RAO
2010-11-01
Full Text Available All the closed loop control system requires the controller for improvement of transient response of the error signal. Though the tuning of PID controller in real time is bit difficult and moreover it lacks the disturbance rejection capability. This paper presents a tuning of PID parameters based on internal model strategy. The advantageous of the proposed control strategy is well described in the paper. To test the validity of the proposed control, it is implemented in brushless dc motor drive. The mathematical model of brushless dc motor (BLDC is presented for control design. In addition the robustness of the control strategy is discussed. The proposed control strategy possesses good transient responses and good load disturbance response. In addition, the proposed control strategy possesses good tracking ability. To test the effectiveness of the proposed strategy, the BLDC is represented in transfer function model and later implemented in test system. The results are presented to validate the proposed control strategy for BLDC drive.
Institute of Scientific and Technical Information of China (English)
JIN Qibing; LIU Qie; WANG Qi; TIAN Yuqi; WANG Yuanfei
2013-01-01
The IMC (Internal Model Control) controller based on robust tuning can improve the robustness and dynamic performance of the system.In this paper,the robustness degree of the control system is investigated based on Maximum Sensitivity (Ms) in depth.And the analytical relationship is obtained between the robustness specification and controller parameters,which gives a clear design criterion to robust IMC controller.Moreover,a novel and simple IMC-PID (Proportional-Integral-Derivative) tuning method is proposed by converting the IMC controller to PID form in terms of the time domain rather than the frequency domain adopted in some conventional IMC-based methods.Hence,the presented IMC-PID gives a good performance with a specific robustness degree.The new IMC-PID method is compared with other classical IMC-PID rules,showing the flexibility and feasibility for a wide range of plants.
A PID de-tuned method for multivariable systems, applied for HVAC plant
Ghazali, A. B.
2015-09-01
A simple yet effective de-tuning of PID parameters for multivariable applications has been described. Although the method is felt to have wider application it is simulated in a 3-input/ 2-output building energy management system (BEMS) with known plant dynamics. The controller performances such as the sum output squared error and total energy consumption when the system is at steady state conditions are studied. This tuning methodology can also be extended to reduce the number of PID controllers as well as the control inputs for specified output references that are necessary for effective results, i.e. with good regulation performances being maintained.
Analysis of Robustness of PID-GPC Based on IMC Structure
Institute of Scientific and Technical Information of China (English)
陈增强; 毛宗星; 等
2003-01-01
Proportion integral differential generalized predictive control(PID-GPC),a new type of generalized predictive control(GPC) is introduced,and its quality is analyzed with internal model contron(IMC).A very important characteristic,which distinguishes GPC from ordinary IMC,and the robust effect are found.At the same time,a robust region is obtained according to the control laws,so that the defect that the robust analysis could be carried out only with stable models is vercome.It is verified that the robustness of PID-GPC is stronger than general GPC.
Globally robust nonlinear PID controllers for robot manipulators with an uncertain Jacobian matrix
Institute of Scientific and Technical Information of China (English)
Chunqing HUANG; Songjiao SHI
2004-01-01
Based on a continuous piecewise-differentiable increasing functions vector, a class of robust nonlinear PID(RN-PID) controllers is proposed for setpoint control with uncertain Jacobian matrix. Globally asymptotic stability is guaranteed and only position and joint velocity measurements are required. And stability problem arising from integral action and integrator windup, are consequendy resolved. Furthermore, RN-PID controllers can be of effective alternative for anti-integrator-wind-up,the control performance would not be very bad in the presence of rough parameter tuning.
Partial synchronization of different chaotic oscillators using robust PID feedback
Energy Technology Data Exchange (ETDEWEB)
Aguilar-Lopez, Ricardo [Departamento de Energia, Universidad Autonoma Metropolitana - Azcapotzalco, San Pablo 180, Reynosa-Tamaulipas, Azcapotzalco, 02200 Mexico, D.F. (Mexico)]. E-mail: raguilar@correo.azc.uam.mx; Martinez-Guerra, Rafael [Departamento de Control Automatico, CINVESTAV IPN, Apartado Postal 14-740, Mexico, D.F. C.P. 07360 (Mexico)]. E-mail: rguerra@ctrl.cinvestav.mx
2007-07-15
This work deals with the partial synchronization problem of two different chaotic oscillators considering model uncertainties in the slave system via control approach. The slave system is forced to follow the master signal via a linearizing controller based on model uncertainty reconstructor which leads to proportional-integral-derivative (PID) control structure. This reconstructor is related with a proportional-derivative (PD) reduced-order observer, it would be considered as a sub-slave system for the original slave of the synchronization procedure. The asymptotic performance of the synchronization methodology is proven via the dynamic of the synchronization error. Numerical experiment illustrates the closed-loop behavior of the proposed methodology.
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Márcio Mendonça
2015-10-01
Full Text Available In this work, it is analyzed a multivariate system control of an alcoholic fermentation process with no minimum phase. The control is made with PID classic controllers associated with a supervisory system based on Fuzzy Systems. The Fuzzy system, a priori, send set-points to PID controllers, but also adds protection functions, such as if the biomass valued is at zero or very close. The Fuzzy controller changes the campaign to prevent or mitigate the paralyzation of the process. Three control architectures based on Fuzzy Control Systems are presented and compared in performance with classic control in different campaigns. The third architecture, in particular, adds an adaptive function. A brief summary of Fuzzy theory and correlated works will be presented. And, finally simulations results, conclusions and future works end the article.
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Jie-Sheng Wang
2014-02-01
Full Text Available A mathematical model of electroslag remelting (ESR process is established based on its technical features and dynamic characteristics. A new multivariable self-tuning proportional-integral-derivative (PID controller tuned optimally by an improved particle swarm optimization (IPSO algorithm is proposed to control the two-input/two-output (TITO ESR process. An adaptive chaotic migration mutation operator is used to tackle the particles trapped in the clustering field in order to enhance the diversity of the particles in the population, prevent premature convergence and improve the search efficiency of PSO algorithm. The simulation results show the feasibility and effectiveness of the proposed control method. The new method can overcome dynamic working conditions and coupling features of the system in a wide range, and it has strong robustness and adaptability.
Relay feedback tuning of robust PID controllers with iso-damping property.
Chen, YangQuan; Moore, Kevin L
2005-02-01
A new tuning method for proportional-integral-derivative (PID) controller design is proposed for a class of unknown, stable, and minimum phase plants. We are able to design a PID controller to ensure that the phase Bode plot is flat, i.e., the phase derivative w.r.t. the frequency is zero, at a given frequency called the "tangent frequency" so that the closed-loop system is robust to gain variations and the step responses exhibit an iso-damping property. At the "tangent frequency," the Nyquist curve tangentially touches the sensitivity circle. Several relay feedback tests are used to identify the plant gain and phase at the tangent frequency in an iterative way. The identified plant gain and phase at the desired tangent frequency are used to estimate the derivatives of amplitude and phase of the plant with respect to frequency at the same frequency point by Bode's integral relationship. Then, these derivatives are used to design a PID controller for slope adjustment of the Nyquist plot to achieve the robustness of the system to gain variations. No plant model is assumed during the PID controller design. Only several relay tests are needed. Simulation examples illustrate the effectiveness and the simplicity of the proposed method for robust PID controller design with an iso-damping property.
A Practical Tuning Method for the Robust PID Controller with Velocity Feed-Back
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Emre Sariyildiz
2015-08-01
Full Text Available Proportional-Integral-Derivative (PID control is the most widely used control method in industrial and academic applications due to its simplicity and efficiency. Several different control methods/algorithms have been proposed to tune the gains of PID controllers. However, the conventional tuning methods do not have sufficient performance and simplicity for practical applications, such as robotics and motion control. The performance of motion control systems may significantly deteriorate by the nonlinear plant uncertainties and unknown external disturbances, such as inertia variations, friction, external loads, etc., i.e., there may be a significant discrepancy between the simulation and experiment if the robustness is not considered in the design of PID controllers. This paper proposes a novel practical tuning method for the robust PID controller with velocity feed-back for motion control systems. The main advantages of the proposed method are the simplicity and efficiency in practical applications, i.e., a high performance robust motion control system can be easily designed by properly tuning conventional PID controllers. The validity of the proposal is verified by giving simulation and experimental results.
The Sine Wave Tuning method: Robust PID controller design in the frequency domain
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Š. Bucz
2015-12-01
Full Text Available The paper presents a novel robust PID controller design method for nominal performance specified in terms of maximum overshoot and settling time. The PID controller design provides guaranteed gain margin GM. The parameter of the tuning rules is a suitably chosen point of the plant frequency response obtained by a sine-wave signal with excitation frequency ωn. Then, the designed controller moves this point into the phase crossover with the required gain margin GM. The couple (ωn;GM is specified with respect to closed-loop performance requirements in terms of ηmax (maximum overshoot and ts (settling time according to developed parabolic dependences. The new approach has been verified on a vast batch of benchmark examples; subsequently, the developed algorithm has been extended to robust PID controller design for plants with unstable zero and unstructured uncertainties.
Analysis of Robustness of PID-GPC Based on IMC Structure%基于IMC结构的PID-GPC的鲁棒性分析
Institute of Scientific and Technical Information of China (English)
陈增强; 毛宗星; 杜升之; 孙青林; 袁著祉
2003-01-01
Proportion integral differential generalized predictive control(PID-GPC), a new type of generalizedpredictive control(GPC) is introduced, and its quality is analyzed with internal model control (IMC). A veryimportant characteristic, which distinguishes GPC from ordinary IMC, and the robust effect are found. At thesame time, a robust region is obtained according to the control laws, so that the defect that the robust analysiscould be carried out only with stable models is overcome. It is verified that the robustness of PID-GPC is strongerthan general GPC.
On the Robustness of Hysteretic Second-Order Systems with PID : iISS approach
Ouyang, Ruiyue; Jayawardhana, Bayu; Andrieu, Vincent
2012-01-01
In this paper, we study the robustness property of a second-order linear plant controlled by a proportional, integral and derivative (PID) controller with a hysteretic actuator. The hysteretic actuator is modeled by a Duhem model that exhibits clockwise (CW) input-output (I/O) dynamics (such as the
Robust PID based power system stabiliser: Design and real-time implementation
Energy Technology Data Exchange (ETDEWEB)
Bevrani, Hassan [Department of Electrical and Computer Eng., University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Hiyama, Takashi [Department of Electrical and Computer Eng., Kumamoto University, Kumamoto (Japan); Bevrani, Hossein [Department of Statistics, University of Tabriz, Tabriz (Iran, Islamic Republic of)
2011-02-15
This paper addresses a new robust control strategy to synthesis of robust proportional-integral-derivative (PID) based power system stabilisers (PSS). The PID based PSS design problem is reduced to find an optimal gain vector via an H{infinity} static output feedback control (H{infinity}-SOF) technique, and the solution is easily carried out using a developed iterative linear matrix inequalities algorithm. To illustrate the developed approach, a real-time experiment has been performed for a longitudinal four-machine infinite-bus system using the Analog Power System Simulator at the Research Laboratory of the Kyushu Electric Power Company. The results of the proposed control strategy are compared with full-order H{infinity} and conventional PSS designs. The robust PSS is shown to maintain the robust performance and minimise the effect of disturbances properly. (author)
Robust PID Steering Control in Parameter Space for Highly Automated Driving
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Mümin Tolga Emirler
2014-01-01
Full Text Available This paper is on the design of a parameter space based robust PID steering controller. This controller is used for automated steering in automated path following of a midsized sedan. Linear and nonlinear models of this midsized sedan are presented in the paper. Experimental results are used to validate the longitudinal and lateral dynamic models of this vehicle. This paper is on automated steering control and concentrates on the lateral direction of motion. The linear model is used to design a PID steering controller in parameter space that satisfies D-stability. The PID steering controller that is designed is used in a simulation study to illustrate the effectiveness of the proposed method. Simulation results for a circular trajectory and for a curved trajectory are presented and discussed in detail. This study is part of a larger research effort aimed at implementing highly automated driving in a midsized sedan.
NN robust based-PID Control of A Two-Link Flexible Robot Manipulator
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Moh. Khairudin
2012-01-01
Full Text Available This paper presents control of a two-link flexible robot manipulator. A planar two-link flexible manipulator that moves in the horizontal plane is considered. A dynamic model of the system is developed using an assumed mode methods. The NN robust based-PID controller is used to reduce a nonlinearities problem that can be efficiently solved. The system responses namely hub angular position, deflection and end-point acceleration responses at both links are obtained and analysed.
Nominal and robust stability regions of optimization-based PID controllers.
Ou, Linlin; Zhang, Weidong; Gu, Danying
2006-07-01
In recent decades, several optimization-based methods have been developed for the proportional-integral-derivative (PID) controller design, and the common feature of these methods is that the controller has only one adjustable parameter. To keep the closed-loop systems stable is an essential requirement for the optimization-based PID controllers. In almost all these methods, however, no exact stability region for the single adjustable parameter was sketched. In this paper, using the proposed analytical procedure based on the dual-locus diagram technique, explicit stability regions of the optimization-based PID controllers are derived for stable, integrating, and unstable processes with time delay in the nominal and perturbed cases, respectively. It is revealed that the proposed analytical procedure is effective for the determination of the nominal and robust stability regions and it offers simplicity and ease of mathematical calculations over other available stability analysis methods. The results in this paper provide some insight into the tuning of the optimization-based PID controllers.
Robust Multivariate Control Charts to Detect Small Shifts in Mean
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Habshah Midi
2011-01-01
Full Text Available The classical multivariate CUSUM and EWMA charts are commonly used to detect small shifts in the mean vectors. It is now evident that those charts are easily affected by outliers which may be due to small or moderate changes in the mean vector. In this paper, we propose a robust multivariate CUSUM and Robust multivariate EWMA charts to remedy the problem of small changed in scatter outliers. Both the empirical and simulation results indicate that the proposed robust multivariate CUSUM and EWMA charts offer substantial improvement over other multivariate CUSUM and EWMA charts. This article also discussed the robustness of the proposed charts, when there is a small or moderate sustained shift in the data set.
Research on the Robustness of an Adaptive PID Control of a Kind of Supersonic Missile
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Gangling Jiao
2013-01-01
Full Text Available In this study, the dynamic characteristic of missile system is viewed as a two-loop system, such as inner loop and outer loop and we design an adaptive PID control strategy for the pitch channel linear model of supersonic missile. The robustness of a double PID controller is analyzed by changing the aerodynamic coefficients. The control law is testified to be stable even the aerodynamic coefficients are changed between 0.7 and 1.7 times of its standard value and the control effect is compared with the sliding mode control strategy. Also the advantage and defect of both control strategy are summarized at the end of this study.
Robust Evaluation of Multivariate Density Forecasts
Dovern, Jonas; Manner, Hans
2016-01-01
We derive new tests for proper calibration of multivariate density forecasts based on Rosenblatt probability integral transforms. These tests have the advantage that they i) do not depend on the ordering of variables in the forecasting model, ii) are applicable to densities of arbitrary dimensions, and iii) have superior power relative to existing approaches. We furthermore develop adjusted tests that allow for estimated parameters and, consequently, can be used as in-sample specification tes...
Intuitive robust stability metric for PID control of self-regulating processes.
Arbogast, Jeffrey E; Beauregard, Brett M; Cooper, Douglas J
2008-10-01
Published methods establish how plant-model mismatch in the process gain and dead time impacts closed-loop stability. However, these methods assume no plant-model mismatch in the process time constant. The work presented here proposes the robust stability factor metric, RSF, to examine the effect of plant-model mismatch in the process gain, dead time, and time constant. The RSF is presented in two forms: an equation form and a visual form displayed on robustness plots derived from the Bode and Nyquist stability criteria. This understanding of robust stability is reinforced through visual examples of how closed-loop performance changes with various levels of plant-model mismatch. One example shows how plant-model mismatch in the time constant can impact closed-loop stability as much as plant-model mismatch in the gain and/or dead time. Theoretical discussion shows that the impact is greater for small dead time to time constant ratios. As the closed-loop time constant used in Internal Model Control (IMC) tuning decreases, the impact becomes significant for a larger range of dead time to time constant ratios. To complete the presentation, the RSF is used to compare the robust stability of IMC-PI tuning to other PI, PID, and PID with Filter tuning correlations.
Robust decentralized PID-based power system stabilizer design using an ILMI approach
Energy Technology Data Exchange (ETDEWEB)
Soliman, M.; Bendary, F.; Mansour, W. [Electrical Power and Machines Dept., Faculty of Engineering, Benha university, 108 Shoubra St., Cairo (Egypt); Elshafei, A.L. [Electrical Power and Machines Dept., Cairo University, Gamma St, Giza (Egypt)
2010-12-15
Thanks to its essential functionality and structure simplicity, proportional-integral-derivative (PID) controllers are commonly used by industrial utilities. A robust PID-based power system stabilizer (PSS) is proposed to properly function over a wide range of operating conditions. Uncertainties in plant parameters, due to variation in generation and load patterns, are expressed in the form of a polytopic model. The PID control problem is firstly reduced to a generalized static output feedback (SOF) synthesis. The derivative action is designed and implemented as a high-pass filter based on a low-pass block to reduce its sensitivity to sensor noise. The proposed design algorithm adopts a quadratic Lyapunov approach to guarantee {alpha}-decay rate for the entire polytope. A constrained structure of Lyapunov function and SOF gain matrix is considered to enforce a decentralized scheme. Setting of controller parameters is carried out via an iterative linear matrix inequality (ILMI). Simulation results, based on a benchmark model of a two-area four-machine test system, are presented to compare the proposed design to a well-tuned conventional PSS and to the standard IEEE-PSS4B stabilizer. (author)
Jin, Q B; Liu, Q; Huang, B
2016-03-01
This paper considers the problem of determining all the robust PID (proportional-integral-derivative) controllers in terms of the gain and phase margins (GPM) for open-loop unstable first order plus time delay (UFOPTD) processes. It is the first time that the feasible ranges of the GPM specifications provided by a PID controller are given for UFOPTD processes. A gain and phase margin tester is used to modify the original model, and the ranges of the margin specifications are derived such that the modified model can be stabilized by a stabilizing PID controller based on Hermite-Biehlers Theorem. Furthermore, we obtain all the controllers satisfying a given margin specification. Simulation studies show how to use the results to design a robust PID controller.
Robust methods for multivariate data analysis A1
DEFF Research Database (Denmark)
Frosch, Stina; Von Frese, J.; Bro, Rasmus
2005-01-01
Outliers may hamper proper classical multivariate analysis, and lead to incorrect conclusions. To remedy the problem of outliers, robust methods are developed in statistics and chemometrics. Robust methods reduce or remove the effect of outlying data points and allow the ?good? data to primarily...
Fault tolerant control of multivariable processes using auto-tuning PID controller.
Yu, Ding-Li; Chang, T K; Yu, Ding-Wen
2005-02-01
Fault tolerant control of dynamic processes is investigated in this paper using an auto-tuning PID controller. A fault tolerant control scheme is proposed composing an auto-tuning PID controller based on an adaptive neural network model. The model is trained online using the extended Kalman filter (EKF) algorithm to learn system post-fault dynamics. Based on this model, the PID controller adjusts its parameters to compensate the effects of the faults, so that the control performance is recovered from degradation. The auto-tuning algorithm for the PID controller is derived with the Lyapunov method and therefore, the model predicted tracking error is guaranteed to converge asymptotically. The method is applied to a simulated two-input two-output continuous stirred tank reactor (CSTR) with various faults, which demonstrate the applicability of the developed scheme to industrial processes.
Multivariable robust digital controller design by convex optimization
2004-01-01
The dissertation is essentially concerned with methods of robust digital multivariable and monovariable controller design. For controller desing, a linear discrete-time model of plant to be controlled is used. The controller robustness is treated by sensitivity frequency analysis(sensitivity is transfer function/matrix of closed loop). Correspondingly to H∞ design, the singular values of frequency responses are used for the analysis.The work is divided into five parts. The first part concerns...
Robust on-line relay automatic tuning of PID control systems
Tan; Lee; Jiang
2000-01-01
In this paper, a robust on-line relay automatic tuning method for PID control systems is developed which expand on the application domain of Astrom's renowned relay autotuning method. In the proposed configuration, a relay is applied to an inner loop of a controller-stabilised process in the usual manner. Using the induced limit cycle oscillations from the closed-loop system, the controller settings may be re-tuned non-iteratively to achieve enhanced performance without disrupting closed-loop control. Two control tuning methodologies are developed -- a direct and an indirect method based on an explicit process model. Simulation examples and a real-time experiment are provided to illustrate the practical appeal and potential advantages of the proposed method over the basic one.
Robust Hierarchical Control for Uncertain Multivariable Hexarotor Systems
Directory of Open Access Journals (Sweden)
Wei Lin
2015-01-01
Full Text Available Multirotor helicopter attracts more attention due to its increased load capacity and being highly maneuverable. However, these helicopters are uncertain multivariable systems, which pose a challenge for their robust controller design. In this paper, a robust two-loop control scheme is proposed for a hexarotor system. The resulted controller consists of a nominal controller and a robust compensator. The robust compensators are added to restrain the influences of uncertainties such as nonlinear dynamics, coupling, parametric uncertainties, and external disturbances. It is proven that the tracking errors are ultimately bounded with specified boundaries by choosing the parameters of the robust compensators. Simulation results on the hexarotor demonstrate the effectiveness of the proposed control method.
Verification of predicted robustness and accuracy of multivariate analysis☆
Markiewicz, P.J.; Matthews, J.C.; Declerck, J.; Herholz, K.
2012-01-01
The assessment of accuracy and robustness of multivariate analysis of FDG-PET brain images as presented in [Markiewicz, P.J., Matthews, J.C., Declerck, J., Herholz, K., 2009. Robustness of multivariate image analysis assessed by resampling techniques and applied to FDG-PET scans of patients with Alzheimer's disease. Neuroimage 46, 472–485.] using a homogeneous sample (from one centre) of small size is here verified using a heterogeneous sample (from multiple centres) of much larger size. Originally the analysis, which included principal component analysis (PCA) and Fisher discriminant analysis (FDA), was established using a sample of 42 subjects (19 Normal Controls (NCs) and 23 Alzheimer's disease (AD) patients) and here the analysis is verified using an independent sample of 166 subjects (86 NCs and 80 ADs) obtained from the ADNI database. It is shown that bootstrap resampling combined with the metric of the largest principal angle between PCA subspaces as well as the deliberate clinical misdiagnosis simulation can predict robustness of the multivariate analysis when used with new datasets. Cross-validation (CV) and the .632 bootstrap overestimated the predictive accuracy encouraging less robust solutions. Also, it is shown that the type of PET scanner and image reconstruction method has an impact on such analysis and affects the accuracy of the verification sample. PMID:21338696
Robust control, multidimensional systems and multivariable Nevanlinna-Pick interpolation
Ball, J A
2009-01-01
The connection between the standard $H^\\infty$-problem in control theory and Nevanlinna-Pick interpolation in operator theory was established in the 1980s, and has led to a fruitful cross-pollination between the two fields since. In the meantime, research in $H^\\infty$-control theory has moved on to the study of robust control for systems with structured uncertainties and to various types of multidimensional systems, while Nevanlinna-Pick interpolation theory has moved on independently to a variety of multivariable settings. Here we review these developments and indicate the precise connections which survive in the more general multidimensional/multivariable incarnations of the two theories.
Robust PID tuning strategy for uncertain plants based on the Kharitonov theorem
Huang; Wang
2000-01-01
In this paper, the Kharitonov theorem for interval plants is exploited for the purpose of synthesizing a stabilizing controller. The aim here is to develop a controller to simultaneously stabilize the four Kharitonov-defined vortex polynomials. Different from the prevailing works, the controller is designed systematically and graphically through the search of a non-conservative Kharitonov region in the controller coefficient parameter plane. The region characterizes all stabilizing PID controllers that stabilize an uncertain plant. Thus the relationship between the Kharitonov region and the stabilizing controller parameters is manifest. Extensively, to further guarantee the system with certain robust safety margins, a virtual gain phase margin tester compensator is added. Stability analysis is carried out. The control system is proved to maintain robustness at least to the pre-specified margins. The synthesized controller with coefficients selected from the obtained non-conservative Kharitonov region can stabilize the concerned uncertain plants and fulfill system specifications in terms of gain margins and phase margins.
Synthesis of a PID-controller of a trim robust control system of an autonomous underwater vehicle
Khozhaev, I. V.; Gayvoronskiy, S. A.
2016-04-01
Autonomous underwater vehicles are often used for performing scientific, emergency or other types of missions under harsh conditions and environments, which can have non-stable, variable parameters. So, the problem of developing autonomous underwater vehicle motion control systems, capable of operating properly in random environments, is highly relevant. The paper is dedicated to the synthesis of a PID-controller of a trim robust control system, capable of keeping an underwater vehicle stable during a translation at different angles of attack. In order to synthesize the PID-controller, two problems were solved: a new method of synthesizing a robust controller was developed and a mathematical model of an underwater vehicle motion process was derived. The newly developed mathematical model structure is simpler than others due to acceptance of some of the system parameters as interval ones. The synthesis method is based on a system poles allocation approach and allows providing the necessary transient process quality in a considered system.
Robust nonlinear PID-like fuzzy logic control of a planar parallel (2PRP-PPR) manipulator.
Londhe, P S; Singh, Yogesh; Santhakumar, M; Patre, B M; Waghmare, L M
2016-07-01
In this paper, a robust nonlinear proportional-integral-derivative (PID)-like fuzzy control scheme is presented and applied to complex trajectory tracking control of a 2PRP-PPR (P-prismatic, R-revolute) planar parallel manipulator (motion platform) with three degrees-of-freedom (DOF) in the presence of parameter uncertainties and external disturbances. The proposed control law consists of mainly two parts: first part uses a feed forward term to enhance the control activity and estimated perturbed term to compensate for the unknown effects namely external disturbances and unmodeled dynamics, and the second part uses a PID-like fuzzy logic control as a feedback portion to enhance the overall closed-loop stability of the system. Experimental results are presented to show the effectiveness of the proposed control scheme.
Energy Technology Data Exchange (ETDEWEB)
Laroche, E. [Lab. des Sciences de l' Image, de l' Informatique et de la Teledetection, UMR 7005, Pole API, 67 - Illkirch (France); Mendes, E. [Laboratoire de Genie Electrique de Paris, UMR 8507, 91 - Gilf sur Yvette (France); Louis, J.P.; Bonnassieux, Y.; Abou-Kandil, H. [Laboratoire d' Electricite, Signaux et Robotique, UPRESA 8029, 94 - Cachan (France)
2002-07-01
In this paper is presented a method for tuning a robust controller well adapted for positioning a load of variable inertia fed by an electric actuator. This method relies on a multi-model pole assignment and minimizes effect of measurement noise. It has been implemented on the benchmark 'fast transitic' located at the LGEP. Thus compared to a classical pole assignment method, the gain of robustness has been shown. The actuator used is an induction machine with flux-oriented control, which is known for its sensitivity to rotor parameter estimation errors. In order to check robustness, a model accounting to this phenomenon is developed and stability margins are computed. (authors)
Harinath, Eranda; Mann, George K I
2008-06-01
This paper describes a design and two-level tuning method for fuzzy proportional-integral derivative (FPID) controllers for a multivariable process where the fuzzy inference uses the inference of standard additive model. The proposed method can be used for any n x n multi-input-multi-output process and guarantees closed-loop stability. In the two-level tuning scheme, the tuning follows two steps: low-level tuning followed by high-level tuning. The low-level tuning adjusts apparent linear gains, whereas the high-level tuning changes the nonlinearity in the normalized fuzzy output. In this paper, two types of FPID configurations are considered, and their performances are evaluated by using a real-time multizone temperature control problem having a 3 x 3 process system.
Directory of Open Access Journals (Sweden)
Mostafa Lotfi Forushani
2012-04-01
Full Text Available This paper presents an optimized controller around the longitudinal axis of multivariable system in one of the aircraft flight conditions. The controller is introduced in order to control the angle of attack from the pitch attitude angle independently (that is required for designing a set of direct force-modes for the longitudinal axis based on particle swarm optimization (PSO algorithm. The autopilot system for military or civil aircraft is an essential component and in this paper, the autopilot system via 6 degree of freedom model for the control and guidance of aircraft in which the autopilot design will perform based on defining the longitudinal and the lateral-directional axes are supposed. The effectiveness of the proposed controller is illustrated by considering HIMAT aircraft. The simulation results verify merits of the proposed controller.
Adjustment of geochemical background by robust multivariate statistics
Zhou, D.
1985-01-01
Conventional analyses of exploration geochemical data assume that the background is a constant or slowly changing value, equivalent to a plane or a smoothly curved surface. However, it is better to regard the geochemical background as a rugged surface, varying with changes in geology and environment. This rugged surface can be estimated from observed geological, geochemical and environmental properties by using multivariate statistics. A method of background adjustment was developed and applied to groundwater and stream sediment reconnaissance data collected from the Hot Springs Quadrangle, South Dakota, as part of the National Uranium Resource Evaluation (NURE) program. Source-rock lithology appears to be a dominant factor controlling the chemical composition of groundwater or stream sediments. The most efficacious adjustment procedure is to regress uranium concentration on selected geochemical and environmental variables for each lithologic unit, and then to delineate anomalies by a common threshold set as a multiple of the standard deviation of the combined residuals. Robust versions of regression and RQ-mode principal components analysis techniques were used rather than ordinary techniques to guard against distortion caused by outliers Anomalies delineated by this background adjustment procedure correspond with uranium prospects much better than do anomalies delineated by conventional procedures. The procedure should be applicable to geochemical exploration at different scales for other metals. ?? 1985.
Alfaro, Víctor M
2007-10-01
In this paper, an index for measuring fragility of proportional integral derivative (PID) controllers is proposed. This index relates the losses of robustness of the control loop when controller parameters change, to the nominal robustness of the control loop. Furthermore, it defines when a PID controller is fragile, nonfragile or resilient.
Review of robust multivariate statistical methods in high dimension.
Filzmoser, Peter; Todorov, Valentin
2011-10-31
General ideas of robust statistics, and specifically robust statistical methods for calibration and dimension reduction are discussed. The emphasis is on analyzing high-dimensional data. The discussed methods are applied using the packages chemometrics and rrcov of the statistical software environment R. It is demonstrated how the functions can be applied to real high-dimensional data from chemometrics, and how the results can be interpreted.
Robust Ranking of Multivariate GARCH Models by Problem Dimension
M. Caporin (Massimiliano); M.J. McAleer (Michael)
2012-01-01
textabstractDuring the last 15 years, several Multivariate GARCH (MGARCH) models have appeared in the literature. Recent research has begun to examine MGARCH specifications in terms of their out-of-sample forecasting performance. We provide an empirical comparison of alternative MGARCH models, namel
Robust Ranking of Multivariate GARCH Models by Problem Dimension
McAleer, Michael; Caporin, Massimiliano
2012-01-01
textabstractDuring the last 15 years, several Multivariate GARCH (MGARCH) models have appeared in the literature. Recent research has begun to examine MGARCH specifications in terms of their out-of-sample forecasting performance. We provide an empirical comparison of alternative MGARCH models, namely BEKK, DCC, Corrected DCC (cDCC), CCC, OGARCH Exponentially Weighted Moving Average, and covariance shrinking, using historical data for 89 US equities. We contribute to the literature in several ...
Wang, Yuan-Jay
2014-03-01
This paper proposes a novel alternative method to graphically compute all feasible gain and phase margin specifications-oriented robust PID controllers for open-loop unstable plus time delay (OLUPTD) processes. This method is applicable to general OLUPTD processes without constraint on system order. To retain robustness for OLUPTD processes subject to positive or negative gain variations, the downward gain margin (GM(down)), upward gain margin (GM(up)), and phase margin (PM) are considered. A virtual gain-phase margin tester compensator is incorporated to guarantee the concerned system satisfies certain robust safety margins. In addition, the stability equation method and the parameter plane method are exploited to portray the stability boundary and the constant gain margin (GM) boundary as well as the constant PM boundary. The overlapping region of these boundaries is graphically determined and denotes the GM and PM specifications-oriented region (GPMSOR). Alternatively, the GPMSOR characterizes all feasible robust PID controllers which achieve the pre-specified safety margins. In particular, to achieve optimal gain tuning, the controller gains are searched within the GPMSOR to minimize the integral of the absolute error (IAE) or the integral of the squared error (ISE) performance criterion. Thus, an optimal PID controller gain set is successfully found within the GPMSOR and guarantees the OLUPTD processes with a pre-specified GM and PM as well as a minimum IAE or ISE. Consequently, both robustness and performance can be simultaneously assured. Further, the design procedures are summarized as an algorithm to help rapidly locate the GPMSOR and search an optimal PID gain set. Finally, three highly cited examples are provided to illustrate the design process and to demonstrate the effectiveness of the proposed method.
A new digital approach to design multivariable robust optimal control systems
Institute of Scientific and Technical Information of China (English)
LIU Xiang; CHEN Lin; SUN You-xian
2005-01-01
This paper presents a new design of robust optimal controller for multivariable system. The row characteristic functions of a linear multivariable system and dynamic decoupling of its equivalent system, were applied to change the transfer function matrix of a closed-loop system into a normal function matrix, so that robustH∞ optimal stability is guaranteed. Furthermore,for the decoupled equivalent control system the l∞ optimization approach is used to have the closed-loop system embody optimal time domain indexes. A successful application on a heater control system verified the excellence of the new control scheme.
Depth-weighted robust multivariate regression with application to sparse data
Dutta, Subhajit
2017-04-05
A robust method for multivariate regression is developed based on robust estimators of the joint location and scatter matrix of the explanatory and response variables using the notion of data depth. The multivariate regression estimator possesses desirable affine equivariance properties, achieves the best breakdown point of any affine equivariant estimator, and has an influence function which is bounded in both the response as well as the predictor variable. To increase the efficiency of this estimator, a re-weighted estimator based on robust Mahalanobis distances of the residual vectors is proposed. In practice, the method is more stable than existing methods that are constructed using subsamples of the data. The resulting multivariate regression technique is computationally feasible, and turns out to perform better than several popular robust multivariate regression methods when applied to various simulated data as well as a real benchmark data set. When the data dimension is quite high compared to the sample size it is still possible to use meaningful notions of data depth along with the corresponding depth values to construct a robust estimator in a sparse setting.
Institute of Scientific and Technical Information of China (English)
余世明; 吴江江; 张端
2011-01-01
This job focuses on the stroke regulation of a class of high-precision metering pumps. A parametertuning method of robust non-fragile PID (proportional-integral-derivative) controllers is proposed with the assumption that a PID controller has additive gain perturbations. An H-infinite robust PID controller can be obtained by solving a linear matrix inequality. This approach can guarantee that the closed-loop control systems is asymptotically stable and the H-infinite norm of the transfer function from the disturbance to the output of a controlled system is less than a given constant to attenuate disturbances. The simulation case shows that the control performance of the proposed strategy is significantly better than the traditional PID approach in the situation with perturbations of controller parameters.
Modern nonparametric, robust and multivariate methods festschrift in honour of Hannu Oja
Taskinen, Sara
2015-01-01
Written by leading experts in the field, this edited volume brings together the latest findings in the area of nonparametric, robust and multivariate statistical methods. The individual contributions cover a wide variety of topics ranging from univariate nonparametric methods to robust methods for complex data structures. Some examples from statistical signal processing are also given. The volume is dedicated to Hannu Oja on the occasion of his 65th birthday and is intended for researchers as well as PhD students with a good knowledge of statistics.
Multivariable robust controller design of ACLS using loop-shaping approach
Dong, Chaoyang; Cui, Haihua; Wang, Qing
2008-10-01
In this paper a multivariable robust controller design approach of the ACLS is accomplished by using robust loop-shaping techniques. In order to avoid the inefficient way of choosing the weight functions by trial-and-error method, the structured genetic algorithm (SGA) approach is introduced, which is capable of simultaneously searching the orders and coefficients of the pre- and post-compensator for weight matrices. According to this approach, engineers can achieve an ideal loop-shape which lies in an appropriate region relating to the desired performance specifications. The effectiveness of this approach is illustrated by the longitudinal equations of a carrier-based aircraft's motion design example.
Comparative Analysis of Pso-Pid and Hu-Pid
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Chanda Thakur
2017-02-01
Full Text Available PID control is an important ingredient of a distributed control system. The controllers are also embedded in many special purpose control systems. PID control is often combined with logic, sequential functions, selectors, and simple function blocks to build the complicated automation systems used for energy production, transportation, and manufacturing. Many sophisticated control strategies, such as model predictive control, are also organized hierarchically. PID control is used at the lowest level; the multivariable controller gives the set points to the controllers at the lower level. The PID controller can thus be said to be the “bread and butter‟ of power system engineering. It is an important component in every control engineer‟s tool box. PID controllers have survived many changes in technology, from mechanics and pneumatics to microprocessors via electronic tubes, transistors, integrated circuits. The microprocessor has had a dramatic influence on the PID controller
Multivariable Super Twisting Based Robust Trajectory Tracking Control for Small Unmanned Helicopter
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Xing Fang
2015-01-01
Full Text Available This paper presents a highly robust trajectory tracking controller for small unmanned helicopter with model uncertainties and external disturbances. First, a simplified dynamic model is developed, where the model uncertainties and external disturbances are treated as compounded disturbances. Then the system is divided into three interconnected subsystems: altitude subsystem, yaw subsystem, and horizontal subsystem. Second, a disturbance observer based controller (DOBC is designed based upon backstepping and multivariable super twisting control algorithm to obtain robust trajectory tracking property. A sliding mode observer works as an estimator of the compounded disturbances. In order to lessen calculative burden, a first-order exact differentiator is employed to estimate the time derivative of the virtual control. Moreover, proof of the stability of the closed-loop system based on Lyapunov method is given. Finally, simulation results are presented to illustrate the effectiveness and robustness of the proposed flight control scheme.
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Tossaporn Chamsai
2015-01-01
Full Text Available The sliding mode control (SMC technique with a first-order low-pass filter (LPF is incorporated with a new adaptive PID controller. It is proposed for tracking control of an uncertain nonlinear system. In the proposed control scheme, the adaptation law is able to update the PID controller online during the control process within a short period. The chattering phenomenon of the SMC can be alleviated by incorporation of a first-order LPF, while the robustness of the control system is similar to that of the sliding mode. In the closed-loop control analysis, the convergence condition in the reaching phase and the existence condition of the sliding mode were analyzed. The stability of the closed-loop control is guaranteed in the sense of Lyapunov’s direct method. The simulations and experimental applications of a speed tracking control of a spark ignition (SI engine via electronic throttle valve control architecture are provided to verify the effectiveness and the feasibility of the proposed control scheme.
Probability modeling for robustness of multivariate LQG designing based on ship lateral motion
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
The robustness of LQG designing for latitudinal movement of ship is mainly discussed, when its hydrodynamic parameters fluctuate around criterion value at random on the proportional distributing. When a given ship state at the speed of 18 kn and the course of 45° under Rank 5 state of sea, and the hydrodynamic parameters of the ship fluctuate at random on the proportional distributing with a range of ±10%,±20%,±30%, the robustness of multivariate LQG designing for ship is analyzed with applying the probability modeling of relative controlling effect. The result of simulating shows that when the hydrodynamic parameters of ship fluctuates the relative controlling effect of the LQG designing submit to normal distribution and the mean value of relative controlling effect has no remarkable changes comparing to that without perturbation of hydrodynamic parameter.
Multivariable H Robust Controller for a Permanent Magnet Synchronous Machine (PMSM
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J. Khedri
2015-03-01
Full Text Available Analytical modeling of the PMSM often involves many simplifying assumptions. The model thus obtained is a model where the physical phenomena and dynamics are neglected during the identification of the process such that the saturation of the magnet circuit and the skin effect. However, the variation of stator resistances, cyclic inductances and moment of inertia due to the temperature and extensive use induce a difference between the process and the nominal mathematical model. Besides since the load torque is external disturbance that can affect the PMSM model, the traditional methods (Bode, Nyquist design… fail to satisfy stability and robust performance. To solve this problem, a robust multivariable H infinity controller is used seeing that the desired performance can be merged in the design phase as performance weights. The effectiveness of the proposed controller is applied for the speed tracking during load changing of a PMSM fed by voltage inverter through experimental study.
US Agency for International Development — PIDS is the web-based system designed to allow data input and consultative sessions by USAID/Liberia's IPs and USAID personnel. It is established and maintained by...
Shabani, Hamed; Vahidi, Behrooz; Ebrahimpour, Majid
2013-01-01
A new PID controller for resistant differential control against load disturbance is introduced that can be used for load frequency control (LFC) application. Parameters of the controller have been specified by using imperialist competitive algorithm (ICA). Load disturbance, which is due to continuous and rapid changes of small loads, is always a problem for load frequency control of power systems. This paper introduces a new method to overcome this problem that is based on filtering technique which eliminates the effect of this kind of disturbance. The object is frequency regulation in each area of the power system and decreasing of power transfer between control areas, so the parameters of the proposed controller have been specified in a wide range of load changes by means of ICA to achieve the best dynamic response of frequency. To evaluate the effectiveness of the proposed controller, a three-area power system is simulated in MATLAB/SIMULINK. Each area has different generation units, so utilizes controllers with different parameters. Finally a comparison between the proposed controller and two other prevalent PI controllers, optimized by GA and Neural Networks, has been done which represents advantages of this controller over others. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.
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Muharrem Imal
2015-01-01
Full Text Available Energy efficiency in heating, ventilating, and air-conditioning (HVAC systems is a primary concern in process projects, since the energy consumption has the highest percentage in HVAC for all processes. Without sacrifice of thermal comfort, to reset the suitable operating parameters, such as the humidity and air temperature, would have energy saving with immediate effect. In this paper, the simulation-optimization approach described the effective energy efficiency for HVAC systems which are used in industrial process. Due to the complex relationship of the HVAC system parameters, it is necessary to suggest optimum settings for different operations in response to the dynamic cooling loads and changing weather conditions during a year. Proportional-integral-derivative (PID programming was developed which can effectively handle the discrete, nonlinear and highly constrained optimization problems. Energy efficiency process has been made by controlling of alternative current (AC drivers for ventilation and exhaust fans, according to supplied air flow capacity and differential air pressure between supplied and exhaust air. Supervisory controller software was developed by using programmable controllers and human machine interface (HMI units. The new designed HVAC control system would have a saving potential of about 40% as compared to the existing operational settings, without any extra cost.
Multivariable Robust Control of a Simulated Hybrid Solid Oxide Fuel Cell Gas Turbine Plant
Energy Technology Data Exchange (ETDEWEB)
Tsai A, Banta L, Tucker D
2010-08-01
This work presents a systematic approach to the multivariable robust control of a hybrid fuel cell gas turbine plant. The hybrid configuration under investigation built by the National Energy Technology Laboratory comprises a physical simulation of a 300kW fuel cell coupled to a 120kW auxiliary power unit single spool gas turbine. The public facility provides for the testing and simulation of different fuel cell models that in turn help identify the key difficulties encountered in the transient operation of such systems. An empirical model of the built facility comprising a simulated fuel cell cathode volume and balance of plant components is derived via frequency response data. Through the modulation of various airflow bypass valves within the hybrid configuration, Bode plots are used to derive key input/output interactions in transfer function format. A multivariate system is then built from individual transfer functions, creating a matrix that serves as the nominal plant in an H{sub {infinity}} robust control algorithm. The controller’s main objective is to track and maintain hybrid operational constraints in the fuel cell’s cathode airflow, and the turbo machinery states of temperature and speed, under transient disturbances. This algorithm is then tested on a Simulink/MatLab platform for various perturbations of load and fuel cell heat effluence. As a complementary tool to the aforementioned empirical plant, a nonlinear analytical model faithful to the existing process and instrumentation arrangement is evaluated and designed in the Simulink environment. This parallel task intends to serve as a building block to scalable hybrid configurations that might require a more detailed nonlinear representation for a wide variety of controller schemes and hardware implementations.
Okou, Francis A.; Akhrif, Ouassima; Dessaint, Louis A.; Bouchard, Derrick
2013-05-01
This papter introduces a decentralized multivariable robust adaptive voltage and frequency regulator to ensure the stability of large-scale interconnnected generators. Interconnection parameters (i.e. load, line and transormer parameters) are assumed to be unknown. The proposed design approach requires the reformulation of conventiaonal power system models into a multivariable model with generator terminal voltages as state variables, and excitation and turbine valve inputs as control signals. This model, while suitable for the application of modern control methods, introduces problems with regards to current design techniques for large-scale systems. Interconnection terms, which are treated as perturbations, do not meet the common matching condition assumption. A new adaptive method for a certain class of large-scale systems is therefore introduces that does not require the matching condition. The proposed controller consists of nonlinear inputs that cancel some nonlinearities of the model. Auxiliary controls with linear and nonlinear components are used to stabilize the system. They compensate unknown parametes of the model by updating both the nonlinear component gains and excitation parameters. The adaptation algorithms involve the sigma-modification approach for auxiliary control gains, and the projection approach for excitation parameters to prevent estimation drift. The computation of the matrix-gain of the controller linear component requires the resolution of an algebraic Riccati equation and helps to solve the perturbation-mismatching problem. A realistic power system is used to assess the proposed controller performance. The results show that both stability and transient performance are considerably improved following a severe contingency.
Wind Turbine Load Mitigation based on Multivariable Robust Control and Blade Root Sensors
Díaz de Corcuera, A.; Pujana-Arrese, A.; Ezquerra, J. M.; Segurola, E.; Landaluze, J.
2014-12-01
This paper presents two H∞ multivariable robust controllers based on blade root sensors' information for individual pitch angle control. The wind turbine of 5 MW defined in the Upwind European project is the reference non-linear model used in this research work, which has been modelled in the GH Bladed 4.0 software package. The main objective of these controllers is load mitigation in different components of wind turbines during power production in the above rated control zone. The first proposed multi-input multi-output (MIMO) individual pitch H" controller mitigates the wind effect on the tower side-to-side acceleration and reduces the asymmetrical loads which appear in the rotor due to its misalignment. The second individual pitch H" multivariable controller mitigates the loads on the three blades reducing the wind effect on the bending flapwise and edgewise momentums in the blades. The designed H" controllers have been validated in GH Bladed and an exhaustive analysis has been carried out to calculate fatigue load reduction on wind turbine components, as well as to analyze load mitigation in some extreme cases.
Institute of Scientific and Technical Information of China (English)
方晓燕; 王丽丹; 段书凯
2013-01-01
Memristor is a kind of nonlinear circuit element with memory function when power off. Its resistance value changes automatically with its charge changing and flux changing which can be used as a controllable parameter in the modern control systems. The proportional-integral-derivative (PID) is still the major control mechanism in the majority of manufacturing industries. In recent years, many researchers have proposed a lot of decoupling PID control systems for solving the strong coupling problem and the problem that the control parameters are difficult to adjust in the control process. In this paper, we present a adaptive single-neuron multivariate decoupling PID controller based on memristor. Based on the structure and principle of the traditional controller, the structure and principle of the bivariate decoupling controller with memristor is established. Then the performance of the bivariate decoupling controller is analyzed and the simulation results are shown. According to experimental simulation results, we find out that the new bivariate decoupling controller has higher control reliability and better adaptability and acts more rapidly than the traditional controller. Finally we get the ideal, adaptive and self-organizing multivariate decoupling PID controller and the better control effect of the new controller is achieved.%为了解决强耦合问题和控制过程中参数难于调节的问题,提出了基于忆阻的自适应单神经元多变量解耦PID控制器,根据传统控制器的结构和原理,构建了两变量解耦控制器的结构.分析了两变量解耦控制器的性能,给出了实验仿真结果.通过实验结果,发现这个新的两变量解耦控制器具有较高的控制可靠性、较好的适应性,比传统的控制器学习速度快.最后得到了一个理想的、自适应、自组织的多变量解耦控制器,并获得了较好的控制效果.
Fuzzy PID controller combines with closed-loop optimal fuzzy reasoning for pitch control system
Li, Yezi; Xiao, Cheng; Sun, Jinhao
2013-03-01
PID and fuzzy PID controller are applied into the pitch control system. PID control has simple principle and its parameters setting are rather easy. Fuzzy control need not to establish the mathematical of the control system and has strong robustness. The advantages of fuzzy PID control are simple, easy in setting parameters and strong robustness. Fuzzy PID controller combines with closed-loop optimal fuzzy reasoning (COFR), which can effectively improve the robustness, when the robustness is special requirement. MATLAB software is used for simulations, results display that fuzzy PID controller which combines with COFR has better performances than PID controller when errors exist.
Institute of Scientific and Technical Information of China (English)
黄春庆; 彭侠夫; 王军平
2008-01-01
As for Cartesian regulation of robot manipulators with uncertain Jacobian matrix, an anti-windup scheme of robust nonlinear PID (RN-PID) controllers is proposed to solve the practical problems arising from integral action and integrator windup in PID-like control systems. Asymptotic stability is guaranteed while position and joint velocity measurements are only required;robustness of the resulting closed-loop system is also guaranteed due to the constraints acting on integral action. Especially, compared with other anti-windup approachs, the proposed algorithm is simpler and more effective for anti-windup design.
Pelvic Inflammatory Disease (PID)
... Management Education & Events Advocacy For Patients About ACOG Pelvic Inflammatory Disease (PID) Home For Patients Search FAQs Pelvic Inflammatory ... Inflammatory Disease (PID) FAQ077, September 2015 PDF Format Pelvic Inflammatory Disease (PID) Gynecologic Problems What is pelvic inflammatory disease ( ...
Multivariate meta-analysis: a robust approach based on the theory of U-statistic.
Ma, Yan; Mazumdar, Madhu
2011-10-30
Meta-analysis is the methodology for combining findings from similar research studies asking the same question. When the question of interest involves multiple outcomes, multivariate meta-analysis is used to synthesize the outcomes simultaneously taking into account the correlation between the outcomes. Likelihood-based approaches, in particular restricted maximum likelihood (REML) method, are commonly utilized in this context. REML assumes a multivariate normal distribution for the random-effects model. This assumption is difficult to verify, especially for meta-analysis with small number of component studies. The use of REML also requires iterative estimation between parameters, needing moderately high computation time, especially when the dimension of outcomes is large. A multivariate method of moments (MMM) is available and is shown to perform equally well to REML. However, there is a lack of information on the performance of these two methods when the true data distribution is far from normality. In this paper, we propose a new nonparametric and non-iterative method for multivariate meta-analysis on the basis of the theory of U-statistic and compare the properties of these three procedures under both normal and skewed data through simulation studies. It is shown that the effect on estimates from REML because of non-normal data distribution is marginal and that the estimates from MMM and U-statistic-based approaches are very similar. Therefore, we conclude that for performing multivariate meta-analysis, the U-statistic estimation procedure is a viable alternative to REML and MMM. Easy implementation of all three methods are illustrated by their application to data from two published meta-analysis from the fields of hip fracture and periodontal disease. We discuss ideas for future research based on U-statistic for testing significance of between-study heterogeneity and for extending the work to meta-regression setting.
Simple method of designing centralized PI controllers for multivariable systems based on SSGM.
Dhanya Ram, V; Chidambaram, M
2015-05-01
A method is given to design multivariable PI/PID controllers for stable and unstable multivariable systems. The method needs only the steady state gain matrix (SSGM). The method is based on the static decoupler design followed by SISO PI/PID controllers design and combining the resulted decoupler and the diagonal PI(D) controllers as the centralized controllers. The result of the present method is shown to be equivalent to the empirical method proposed by Davison EJ. Multivariable tuning regulators: the feed-forward and robust control of general servo-mechanism problem. IEEE Trans Autom Control 1976;21:35-41. Three simulation examples are given. The performance of the controllers is compared with that of the reported centralized controller based on the multivariable transfer function matrix.
Robust Multivariable Feedback Control of Natural Gas-Diesel RCCI Combustion
Indrajuana, A.; Bekdemir, C.; Luo, X.; Willems, F.P.T.
2016-01-01
Advanced combustion concepts such as Reactivity Controlled Compression Ignition (RCCI) demonstrate very high thermal efficiencies combined with ultra low NOx emissions. As RCCI is sensitive for operating conditions, closed-loop control is a crucial enabler for stable and robust combustion. The
Robust Multivariable Feedback Control of Natural Gas-Diesel RCCI Combustion
Indrajuana, A.; Bekdemir, C.; Luo, X.; Willems, F.P.T.
2016-01-01
Advanced combustion concepts such as Reactivity Controlled Compression Ignition (RCCI) demonstrate very high thermal efficiencies combined with ultra low NOx emissions. As RCCI is sensitive for operating conditions, closed-loop control is a crucial enabler for stable and robust combustion. The feedb
Robust Nonlinear Causality Analysis of Non-Stationary Multivariate Physiological Time Series.
Schaeck, Tim; Muma, Michael; Feng, Mengling; Guan, Cuntai; Zoubir, Abdelhak
2017-05-26
An important research area in biomedical signal processing is that of quantifying the relationship between simultaneously observed time series and to reveal interactions between the signals. Since biomedical signals are potentially non-stationary and the measurements may contain outliers and artifacts, we introduce a robust time-varying generalized partial directed coherence (rTV-gPDC) function. The proposed method, which is based on a robust estimator of the timevarying autoregressive (TVAR) parameters, is capable of revealing directed interactions between signals. By definition, the rTV-gPDC only displays the linear relationships between the signals. We therefore suggest to approximate the residuals of the TVAR process, which potentially carry information about the nonlinear causality by a piece-wise linear time-varying moving-average (TVMA) model. The performance of the proposed method is assessed via extensive simulations. To illustrate the method's applicability to real-world problems, it is applied to a neurophysiological study that involves intracranial pressure (ICP), arterial blood pressure (ABP), and brain tissue oxygenation level (PtiO2) measurements. The rTV-gPDC reveals causal patterns that are in accordance with expected cardiosudoral meachanisms and potentially provides new insights regarding traumatic brain injuries (TBI). The rTV-gPDC is not restricted to the above problem but can be useful in revealing interactions in a broad range of applications.
Fliess, Michel; Join, Cédric
2008-01-01
International audience; Intelligent PID controllers, or i-PID controllers, are PID controllers where the unknown parts of the plant, which might be highly nonlinear and/or time-varying, are taken into account without any modeling procedure. Our main tool is an online numerical differentiator, which is based on easily implementable fast estimation and identification techniques. Several numerical experiments demonstrate the efficiency of our method when compared to more classic PID regulators.
Pelvic Inflammatory Disease (PID)
... the ectopic pregnancy is not diagnosed early. Chronic pelvic pain —PID may lead to long-lasting pelvic pain. Who is at risk of PID? PID can ... lead to pelvic inflammatory disease and infertility. Chronic Pelvic Pain: Persistent pain in the pelvic region that has ...
Development of Control Models and a Robust Multivariable Controller for Surface Shape Control
Energy Technology Data Exchange (ETDEWEB)
Winters, Scott Eric [Univ. of California, Davis, CA (United States)
2003-06-18
Surface shape control techniques are applied to many diverse disciplines, such as adaptive optics, noise control, aircraft flutter control and satellites, with an objective to achieve a desirable shape for an elastic body by the application of distributed control forces. Achieving the desirable shape is influenced by many factors, such as, actuator locations, sensor locations, surface precision and controller performance. Building prototypes to complete design optimizations or controller development can be costly or impractical. This shortfall, puts significant value in developing accurate modeling and control simulation approaches. This thesis focuses on the field of adaptive optics, although these developments have the potential for application in many other fields. A static finite element model is developed and validated using a large aperture interferometer system. This model is then integrated into a control model using a linear least squares algorithm and Shack-Hartmann sensor. The model is successfully exercised showing functionality for various wavefront aberrations. Utilizing a verified model shows significant value in simulating static surface shape control problems with quantifiable uncertainties. A new dynamic model for a seven actuator deformable mirror is presented and its accuracy is proven through experiment. Bond graph techniques are used to generate the state space model of the multi-actuator deformable mirror including piezo-electric actuator dynamics. Using this verified model, a robust multi-input multi-output (MIMO) H_{∞} controller is designed and implemented. This controller proved superior performance as compared to a standard proportional-integral controller (PI) design.
Balabin, Roman M; Smirnov, Sergey V
2012-04-07
Modern analytical chemistry of industrial products is in need of rapid, robust, and cheap analytical methods to continuously monitor product quality parameters. For this reason, spectroscopic methods are often used to control the quality of industrial products in an on-line/in-line regime. Vibrational spectroscopy, including mid-infrared (MIR), Raman, and near-infrared (NIR), is one of the best ways to obtain information about the chemical structures and the quality coefficients of multicomponent mixtures. Together with chemometric algorithms and multivariate data analysis (MDA) methods, which were especially created for the analysis of complicated, noisy, and overlapping signals, NIR spectroscopy shows great results in terms of its accuracy, including classical prediction error, RMSEP. However, it is unclear whether the combined NIR + MDA methods are capable of dealing with much more complex interpolation or extrapolation problems that are inevitably present in real-world applications. In the current study, we try to make a rather general comparison of linear, such as partial least squares or projection to latent structures (PLS); "quasi-nonlinear", such as the polynomial version of PLS (Poly-PLS); and intrinsically non-linear, such as artificial neural networks (ANNs), support vector regression (SVR), and least-squares support vector machines (LS-SVM/LSSVM), regression methods in terms of their robustness. As a measure of robustness, we will try to estimate their accuracy when solving interpolation and extrapolation problems. Petroleum and biofuel (biodiesel) systems were chosen as representative examples of real-world samples. Six very different chemical systems that differed in complexity, composition, structure, and properties were studied; these systems were gasoline, ethanol-gasoline biofuel, diesel fuel, aromatic solutions of petroleum macromolecules, petroleum resins in benzene, and biodiesel. Eighteen different sample sets were used in total. General
Khoshravesh, Mojtaba; Sefidkouhi, Mohammad Ali Gholami; Valipour, Mohammad
2017-07-01
The proper evaluation of evapotranspiration is essential in food security investigation, farm management, pollution detection, irrigation scheduling, nutrient flows, carbon balance as well as hydrologic modeling, especially in arid environments. To achieve sustainable development and to ensure water supply, especially in arid environments, irrigation experts need tools to estimate reference evapotranspiration on a large scale. In this study, the monthly reference evapotranspiration was estimated by three different regression models including the multivariate fractional polynomial (MFP), robust regression, and Bayesian regression in Ardestan, Esfahan, and Kashan. The results were compared with Food and Agriculture Organization (FAO)-Penman-Monteith (FAO-PM) to select the best model. The results show that at a monthly scale, all models provided a closer agreement with the calculated values for FAO-PM ( R 2 > 0.95 and RMSE < 12.07 mm month-1). However, the MFP model gives better estimates than the other two models for estimating reference evapotranspiration at all stations.
Directory of Open Access Journals (Sweden)
Christian Hunter
2015-10-01
Full Text Available Considering water resource scarcity and uncertainty in climate and demand futures, decision-makers require techniques for sustainability analysis in resource management. Through unclear definitions of “sustainability”, however, traditional indices for resource evaluation propose options of limited flexibility by adopting static climate and demand scenarios, limiting analysis variables to a particular water-use group and time. This work proposes a robust, multivariate, dynamic sustainability evaluation technique and corresponding performance indicator called Measure of Sustainability (MoS for resource management that is more adapted to withstand future parameter variation. The range of potential future climate and demand scenarios is simulated through a calibrated hydrological model of Copiapó, Chile, a case study example of an arid watershed under extreme natural and anthropogenic water stresses. Comparing MoS and cost rankings of proposed water management schemes, this paper determines that the traditional evaluation method not only underestimates future water deficits, but also espouses solutions without considering uncertainties in supply and demand. Given the uncertainty of the future and the dependence of resources upon climate and market trajectories, the MoS methodology proposes solutions that, while perhaps are not the most optimal, are robust to variations in future parameter values and are thus the best water management options in a stochastic natural world.
Discrete PID Tuning Using Artificial Intelligence Techniques
Directory of Open Access Journals (Sweden)
Petr DOLEŽEL
2009-06-01
Full Text Available PID controllers are widely used in industry these days due to their useful properties such as simple tuning or robustness. While they are applicable to many control problems, they can perform poorly in some applications. Highly nonlinear system control with constrained manipulated variable can be mentioned as an example. The point of the paper is to string together convenient qualities of conventional PID control and progressive techniques based on Artificial Intelligence. Proposed control method should deal with even highly nonlinear systems. To be more specific, there is described new method of discrete PID controller tuning in this paper. This method tunes discrete PID controller parameters online through the use of genetic algorithm and neural model of controlled system in order to control successfully even highly nonlinear systems. After method description and some discussion, there is performed control simulation and comparison to one chosen conventional control method.
Sexton, David M. H.; Murphy, James M.
2012-06-01
A method for providing probabilistic climate projections, which applies a Bayesian framework to information from a perturbed physics ensemble, a multimodel ensemble and observations, was demonstrated in an accompanying paper. This information allows us to account for the combined effects of more sources of uncertainty than in any previous study of the equilibrium response to doubled CO2 concentrations, namely parametric and structural modelling uncertainty, internal variability, and observational uncertainty. Such probabilistic projections are dependent on the climate models and observations used but also contain an element of expert judgement. Two expert choices in the methodology involve the amount of information used to (a) specify the effects of structural modelling uncertainty and (b) represent the observational metrics that constrain the probabilistic climate projections. These choices, effected by selecting how many multivariate eigenvectors of a large set of climate variables to retain in our analysis, are investigated in more detail. We also show sensitivity tests that explore a range of key expert choices. For changes in annual global mean temperature and regional changes over England and Wales and Northern Europe, the variations in the projections across the sensitivity studies are small compared to the overall uncertainty, demonstrating that the projections are robust to reasonable variations in key assumptions. We are therefore confident that, despite sampling sources of uncertainty more comprehensively than previously, the improved multivariate treatment of observational metrics has narrowed the probability distribution of climate sensitivity consistent with evidence currently available. Our 5th, 50th, and 95th percentiles are in the range 2.2-2.4, 3.2-3.3, and 4.1-4.5K, respectively. The main caveat is that the handling of structural uncertainty does not account for systematic errors common to the current set of climate models and finding methods to
Ruggieri, Flavia; Gil, Raúl A; Fernandez-Turiel, Jose-Luis; Saavedra, Julio; Gimeno, Domingo; Lobo, Agustin; Martinez, Luis D; Rodriguez-Gonzalez, Alejandro
2012-04-30
A method to obtain robust information on short term leaching behaviour of volcanic ashes has been developed independently on the sample age. A mixed factorial design (MFD) was employed as a multivariate strategy for the evaluation of the effects of selected control factors and their interactions (amount of sample (A), contact time (B), and liquid to solid ratio or L/S (C)) on the leaching process of selected metals (Na, K, Mg, Ca, Si, Al, V, Mn, Fe, and Co) and anions (Cl(-) and SO(4)(2-)). Box plots of the data acquired were used to evaluate the reproducibility achieved at different experimental conditions. Both the amount of sample (A) and leaching time (B) had a significant effect on the element stripping whereas the L/S ratio influenced only few elements. The lowest dispersion values have been observed when 1.0 g was leached with an L/S ratio equal to 10, shaking during 4 h. The entire method is completed within few hours, and it is simple, feasible and reliable in laboratory conditions. Copyright © 2012 Elsevier B.V. All rights reserved.
Pelvic inflammatory disease (PID) -- aftercare
... this page: //medlineplus.gov/ency/patientinstructions/000710.htm Pelvic inflammatory disease (PID) - aftercare To use the sharing features on ... have just seen your health care provider for pelvic inflammatory disease (PID). PID refers to an infection of the ...
The ToxiRAE Pro PID measures total volatile organic compounds (VOCs) using a photoionization detector (PID). This sensor can be programmed to measure concentrations of a specified compound automatically and has a real time reading of VOC concentrations in parts per million (ppm) ...
The ToxiRAE Pro PID measures total volatile organic compounds (VOCs) using a photoionization detector (PID). This sensor can be programmed to measure concentrations of a specified compound automatically and has a real time reading of VOC concentrations in parts per million (ppm) ...
Institute of Scientific and Technical Information of China (English)
伍松; 张彦会
2012-01-01
Because of the positive and negative piezoelectric effect of intelligent Piezo-electric material, the application of it has been more and more in noise and active vibration controlling.According to thin plate theory and finite element method piezoelectric plate is discretized to deduce finite element dynamics equation of intelligent Piezo-electric plate.In addition the plate is controlled by applying multivariable MIC and net PID,and response curves are analyzed through digital simulation for several situations by matlab numerical systenuThe result proves that the method can effectively control vibration of the laminated plate to reach the research purpose of active vibration control and suppression for laminated plate ,in particular in situation of model being unmatched,which well solve variable control problems of intelligent plate model with strong adaptability.%智能压电材料由于它的正逆压电效应,故在噪声及振动的主动振控制中应用越来越多,基于薄板理论并且利用有限元的方法对压电板进行离散化,推导出智能压电板的有限元动力学方程,并且应用多变量MIC网络神经PID算法,对其进行控制,利用MATLAB编程分几种情形进行数字仿真,对响应曲线进行分析,仿真结果表明该方法能有效抑制层合板的振动,达到对智能层合板的主动控制,特别是模型失配时仍然有较好的控制,很好地解决了这类智能板模型易变的控制问题,相对一般的控制方法具有较强适应性.
Enhancement of Heat Exchanger Control Using Improved PID Controller
Directory of Open Access Journals (Sweden)
Gopalakrishna G.
2009-08-01
Full Text Available The Proportional, Integral and Derivative (PID controllers are widely used in industrial applications. Their popularity comes from their robust performance and also from their functional simplicity. Temperature control of double tube heat exchanger system is presented and ant colony algorithm for optimizing PID parameters of temperature controller is presented in this paper on the basis of conventional PID controller. Temperature controller based on ant colony optimization for double tube heat exchanger is designed. Simulation results show that, for the case of heat exchanger system, ACO-PID is good model and generalize well. The closed loop unit step response obtained with the proposed PID compares favorably with the one achieved using a conventional PID controller with dynamic closed-loop simulation. More important, the proposed approach takes a fraction of the time spent by the standard technique, without the need of perturbing the closed-loop system.
Directory of Open Access Journals (Sweden)
Horaţiu Ştefan Grif
2011-06-01
Full Text Available The paper describes the implementation and the tuning of a digital PID controller used in a daylight control application. Due to the fact that the process is unknown, an experimental method, Ziegler-Nichols, for the tuning of the PID controller was used. The obtained PID parameters do not offer a good behavior of the ALCS. To improve the performances of the ALCS, supplementary tuning of the PID parameters, via step response analysis, was made. The step response acquiring and analysis may have an expensive time cost. To avoid the time cost the present paper offers an algorithm which guide the designer to chose, in a slight manner, not only a set but a set family of the PID parameters for which the ALCS has a good behavior. Also, the algorithm presents the way how the ALCS user can set his desired ALCS speed reaction to the daylight variations.
DEFF Research Database (Denmark)
Sørensen, John Dalsgaard; Rizzuto, Enrico; Narasimhan, Harikrishna
2012-01-01
More frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure combined with increased requirements to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of structures......, a theoretical and risk-based framework is presented which facilitates the quantification of robustness, and thus supports the formulation of pre-normative guidelines....
Cates W; Weisner, P J; Goodrich, J T
1982-08-01
Once the condition of pelvic inflammatory disease (PID) has been diagnosed clinicans should initiate immediate therapy. If antibiotics are withheld until a specific microbiologic diagnosis is obtained, the possibility of laboratory error and of processing delays hinders appropriate therapy. Evolving knowledge of the definition, etiology, and treatment of PID provides additional rationale for immediate antibiotic administration. PID, which refers to the clinical syndrome attributed to the ascending spread of microorganisms from the vaginal and endocervix to the fallopian tubes and contiguous structures, includes the clinical entities of endometritis, salpingitis, and parametritis, and/or peritonitis. Clinical diagnosis usually involves a history of lower abdominal pain, lower abdominal tenderness, cervical motion tenderness, and adnexal tenderness. Many organisms play a role in the pathogenesis of this syndrome, and clinicians should initiate treatment regimens which are active against the broadest range of pathogens. The treatment of choice is not established. No single agent is active against the entire spectrum of pathogens. Several antimicrobial combinations provide broad spectrum activity against the major pathogens in vitro, but many have not been adequatley evaluated for clinical efficacy in PID. Drugs with optimal anaerobic activity are perferred in patients with a pelvic mass or IUD associated PID. In most other women, drugs with optimal activity against N. gonorrhoea and C. trachomatis may be preferred. Due to the severe longterm complications resulting from PID, including infertility and ectopic pregnancy, clinicians should seriously consider hospitalizing women with PID whenever practical. Criteria for hospitalization are outlined.
Pelvic inflammatory disease (PID)
... for cancer) Getting an intrauterine device (IUD) Miscarriage Abortion In the United States, nearly 1 million women ... gonorrhea, chlamydia, or other causes of PID. Pelvic ultrasound or CT scan to see what else may ...
Institute of Scientific and Technical Information of China (English)
张媛媛; 徐科军; 黄云志; 陈佳臻; 滕勤; 谈建
2011-01-01
宽域废气氧(Universal Exhaust Gas Oxygen,UEGO)传感器可以在很宽的空燃比范围内提供有效的氧含量信号,它的结构特殊,必须配以控制器才能使用.利用鲁棒PID算法控制UEGO控制器中象电压的大小和方向,并将泵电压反馈作用在UEGO传感器上.检测UEGO传感器上的泵电流,并设计非线性校正环节对其进行校正,校正输出值即为过量空气系数(A).利用dSPACE实时仿真系统实现UEGO控制器,并在汽车化油器发动机台架上进行相关实验.实验数据表明,在λ值静态和动态变化时,UEGO控制器都具有良好的鲁棒性和运行性能,响应快速且精度良好.%Universal exhaust gas oxygen (UEGO) sensor can effectively provide the information of oxygen content in wide scope of air-fuel ratio. Due to its special structure, it cannot work normally without a controller. Therefore a robust PID algorithm was applied to the controller of UEGO sensor for controlling the value and direction of the pump cell voltage and exerting a feedback control action on the sensor. The pump cell current was detected and a nonlinear corrector for the pump cell current was designed, which results in an excess air factor(λ ). UEGO controller was implemented by means of dSPACE real time simulation system, and experiments were conducted on a carburetor engine. Experimental results show that the UEGO controller has strong robustness and good running performance. It can achieve quick response and precision measurement when λ changes in static and dynamic modes.
Pelvic Inflammatory Disease (PID) Statistics
... Search Form Controls Cancel Submit Search the CDC Pelvic Inflammatory Disease (PID) Note: Javascript is disabled or is not ... Twitter STD on Facebook Sexually Transmitted Diseases (STDs) Pelvic Inflammatory Disease (PID) Statistics Recommend on Facebook Tweet Share Compartir ...
PID Controller with Operational Amplifier
Directory of Open Access Journals (Sweden)
Cristian Paul Chioncel
2009-01-01
Full Text Available The paper presents a PID controller made with LM741 operational amplifier that implement the PID controllers laws and allow for a widerange of applications of in the field of automatic control of technicalprocesses and systems.
Analysis & Control of Inverted Pendulum System Using PID Controller
Directory of Open Access Journals (Sweden)
Vivek Kumar pathak
2017-05-01
Full Text Available This Analysis designs a two-loop proportional–integral–derivative (PID controller for an inverted cart– pendulum system via pole placement technique, where the (dominant closed-loop poles to be placed at the desired locations are obtained from an Linear quadratic regulator (LQR design. It is seen that in addition to yielding better responses (because of additional integral action than this LQR (equivalent to two-loop PD controller design, the proposed PID controller is robust enough. The performance and of the PID compensation are verified through simulations as well as experiments.
Sadoul, Bastien; Leguen, Isabelle; Colson, Violaine; Friggens, Nicolas C; Prunet, Patrick
2015-03-01
Robustness is a complex trait difficult to characterize and phenotype. In the present study, two features of robustness in rainbow trout were investigated: sensitivity and resilience to an acute stressor. For that purpose, oxygen consumption, cortisol release, group dispersion and group activity of two isogenic lines of juvenile rainbow trout were followed before and after an environmental challenge. The effect of a 4h confinement protocol (~140kg/m(3)), which is generally considered as a highly stressful challenge, was investigated. Temporal patterns produced by this experiment were analyzed using multivariate statistics on curve characteristics to describe physiological and behavioral adaptive systems for each isogenic line. The two isogenic lines were found to be highly divergent in their corticosteroid reactivity. However, no correlation between physiological and behavioral sensitivity or resilience was observed. Furthermore, the multivariate analysis results indicated two separate and independent fish group coping strategies, i.e. by favoring either behavioral or physiological responses. In addition, considerable intra-line variabilities were observed, suggesting the importance of micro-environment effects on perturbation sensitivities. In this context, cortisol release rate variability was found to be related to the pre-stress social environment, with a strong correlation between pre-stress aggressiveness and cortisol release rate amplitude. Overall, this approach allowed us to extract important characteristics from dynamic data in physiology and behavior to describe components of robustness in two isogenic lines of rainbow trout. Copyright © 2014 Elsevier Inc. All rights reserved.
Variable Structure PID Control to Prevent Integrator Windup
Hall, C. E.; Hodel, A. S.; Hung, J. Y.
1999-01-01
PID controllers are frequently used to control systems requiring zero steady-state error while maintaining requirements for settling time and robustness (gain/phase margins). PID controllers suffer significant loss of performance due to short-term integrator wind-up when used in systems with actuator saturation. We examine several existing and proposed methods for the prevention of integrator wind-up in both continuous and discrete time implementations.
Robust Dissipative Control for Linear Multi-variable Systems%线性多变量系统的鲁棒耗散控制
Institute of Scientific and Technical Information of China (English)
邵汉永; 冯纯伯
2005-01-01
Robust quadratic dissipative control for a class of linear multi-variable systems with parameter uncertainties is considered, where the uncertainties are expressed in a linear fractional form.For the nominal system without uncertainties, the equivalence between quadratic dissipativeness and positive realness is established, and conditions are derived for linear systems to be quadratic dissipative. As for uncertain systems, it is shown that the robust quadratic dissipative control problem for the uncertain system can be reduced to the corresponding problem for a related system without uncertainties. The control problem concerned can be solved using LMI approach. The results of the paper unify existing results on H∞ control and positive real control and provide a more flexible and less conservative control design method.
Design of PID Controller for Maglev System Based on an Improved PSO with Mixed Inertia Weight
Directory of Open Access Journals (Sweden)
Rongrong Song
2014-06-01
Full Text Available A Maglev system was modeled by the exact feedback linearization to achieve two same linear subsystems. The proportional-integral-differential controllers (PID based on particle swarm optimization (PSO algorithm with four different inertia weights were then used to regulate both linear subsystems. These different inertia weights were Fixed Inertia Weight (FIW, Linear Descend Inertia Weight (LIW, Linear Differential Descend Inertia Weight (LDW, and mixed inertia weight (FIW–LIW-LDW. On the other hand, the parameters of the PSO-PID controllers via mixed inertia weight (FIW–LIW-LDW were optimized, the parameter values in the electromagnet 1 and electromagnet 2 were both 0.4. Simulation results demonstrate that the control performance and robustness of PSO-PID based on mixed inertia weight (FIW–LIW-LDW was superior to that of three PSO-PID controllers based on single inertia weights. For electromagnet 1, the overshoot of PSO-PID controller with mixed inertia weight reduced 3.36% than that of PSO-PID controller with FIW, 5.81% than that of PSO-PID controller with LIW, and 6.34% than that of PSO-PID controller with LDW; for electromagnet 2, the overshoot of PSO-PID controller with mixed inertia weight reduced 1.07% than that of PSO-PID controller with FIW, 12.56% than that of PSO-PID controller with LIW, 7.97% than that of PSO-PID controller with LDW; the adjusting time of PSO-PID controller with mixed inertia weight reduced 0.395s than that of PSO-PID controller with FIW, 34.1s than that of PSO-PID controller with LIW, and 33.494s than that of PSO-PID controller with LDW
Energy Technology Data Exchange (ETDEWEB)
Pei, L.; Klebaner, A.; Theilacker, J.; Soyars, W.; Martinez, A.; Bossert, R.; DeGraff, B.; Darve, C.; /Fermilab
2011-06-01
The Horizontal Test Stand (HTS) SRF Cavity and Cryomodule 1 (CM1) of eight 9-cell, 1.3GHz SRF cavities are operating at Fermilab. For the cryogenic control system, how to hold liquid level constant in the cryostat by regulation of its Joule-Thompson JT-valve is very important after cryostat cool down to 2.0 K. The 72-cell cryostat liquid level response generally takes a long time delay after regulating its JT-valve; therefore, typical PID control loop should result in some cryostat parameter oscillations. This paper presents a type of PID parameter self-optimal and Time-Delay control method used to reduce cryogenic system parameters oscillation.
Pei, L; Theilacker, J; Soyars, W; Martinez, A; Bossert, R; DeGraff, B; Darve, C
2012-01-01
The Horizontal Test Stand (HTS) SRF Cavity and Cryomodule 1 (CM1) of eight 9-cell, 1.3GHz SRF cavities are operating at Fermilab. For the cryogenic control system, how to hold liquid level constant in the cryostat by regulation of its Joule-Thompson JT-valve is very important after cryostat cool down to 2.0 K. The 72-cell cryostat liquid level response generally takes a long time delay after regulating its JT-valve; therefore, typical PID control loop should result in some cryostat parameter oscillations. This paper presents a type of PID parameter self-optimal and Time-Delay control method used to reduce cryogenic system parameters' oscillation.
Wind turbine pitch control using ICPSO-PID algorithm
DEFF Research Database (Denmark)
Xu, Chang; Tian, Qiangqiang; Shen, Wen Zhong
2013-01-01
of improved cooperative particle swarm optimization (ICPSO) and PID, subsequently, it was used to tune the pitch controller parameters; thus the difficulty in PID tuning was removed when a wind speed was above the rated speed. It was indicated that the proposed optimization algorithm can tune the pitch...... with ICPSO-PID algorithm has a smaller overshoot, a shorter tuning time and better robustness. The design method proposed in the paper can be applied in a practical electro-hydraulic pitch control system for WTG......., a pitch controller was designed based on power and wind speed and by considering the inertia and delay characteristics of a pitch-control system to achieve a constant power output when a wind speed was beyond the rated one. A novel ICPSO-PID control algorithm was proposed based on a combination...
WS/PIDS: standard interoperable PIDS in web services environments.
Vasilescu, E; Dorobanţu, M; Govoni, S; Padh, S; Mun, S K
2008-01-01
An electronic health record depends on the consistent handling of people's identities within and outside healthcare organizations. Currently, the Person Identification Service (PIDS), a CORBA specification, is the only well-researched standard that meets these needs. In this paper, we introduce WS/PIDS, a PIDS specification for Web Services (WS) that closely matches the original PIDS and improves on it by providing explicit support for medical multimedia attributes. WS/PIDS is currently supported by a test implementation, layered on top of a PIDS back-end, with Java- and NET-based, and Web clients. WS/PIDS is interoperable among platforms; it preserves PIDS semantics to a large extent, and it is intended to be fully compliant with established and emerging WS standards. The specification is open source and immediately usable in dynamic clinical systems participating in grid environments. WS/PIDS has been tested successfully with a comprehensive set of use cases, and it is being used in a clinical research setting.
Fuzzy Auto-adjust PID Controller Design of Brushless DC Motor
Yuanxi, Wang; Yali, Yu; Guosheng, Zhang; Xiaoliang, Sheng
Using conventional PID control method, to guarantee the rapidity and small overshoot dynamic and static performance of the BLDCM (brushless DC motor) system is out of the question. The control method to combine fuzzy control with PID control was fit the multivariable strong coupling nonlinear characteristic of BLDCM system. Matlab/Simulink simulation model had been built. The result of computer simulation shows that, compared with the conventional PID controller, the dynamic and static performance of fuzzy auto-adjust PID controller are put forward to optimize. The research work of this paper has profound significance for high precision controller design.
Multi-loop decentralized PID control based on covariance control criteria: an LMI approach.
Huang, Xin; Huang, Biao
2004-01-01
PID control is well known and widely applied in industry and many design algorithms are readily available in the literature. However, systematic design of multi-loop or decentralized PID control for multivariable processes to meet certain objectives simultaneously is still a challenging task. Designing multi-loop PID controllers such that the process variables satisfy the generalized covariance constraints is studied in this paper. A convergent computational algorithm is proposed to calculate the multi-loop PID controller for a process with stable disturbances. This algorithm is then extended to a process with random-walk disturbances. The feasibility of the proposed algorithm is verified by applying it to several simulation examples.
Research Trends for PID Controllers
Directory of Open Access Journals (Sweden)
Antonio Visioli
2012-01-01
Full Text Available This paper analyses the most significant issues that have been recently been addressed by researchers in the field of Proportional-Integral-Derivative (PID controllers. In particular, the most recent techniques proposed for tuning and designing PID-based control structures are briefly reviewed, together with methods for assessing their performance. Finally, fractional-order and event-based PID controllers are presented among the most significant developments in the field.
Tuning of Fuzzy PID Controllers
DEFF Research Database (Denmark)
Jantzen, Jan
1998-01-01
Since fuzzy controllers are nonlinear, it is more difficult to set the controller gains compared to proportional-integral-derivative (PID) controllers. This research paper proposes a design procedure and a tuning procedure that carries tuning rules from the PID domain over to fuzzy single......-loop controllers. The idea is to start with a tuned, conventional PID controller, replace it with an equivalent linear fuzzy controller, make the fuzzy controller nonlinear, and eventually fine-tune the nonlinear fuzzy controller. This is relevant whenever a PID controller is possible or already implemented....
A Proposal of Adaptive PID Controller Based on Reinforcement Learning
Institute of Scientific and Technical Information of China (English)
WANG Xue-song; CHENG Yu-hu; SUN Wei
2007-01-01
Aimed at the lack of self-tuning PID parameters in conventional PID controllers, the structure and learning algorithm of an adaptive PID controller based on reinforcement learning were proposed. Actor-Critic learning was used to tune PID parameters in an adaptive way by taking advantage of the model-free and on-line learning properties of reinforcement learning effectively. In order to reduce the demand of storage space and to improve the learning efficiency,a single RBF neural network was used to approximate the policy function of Actor and the value function of Critic simultaneously. The inputs of RBF network are the system error, as well as the first and the second-order differences of error. The Actor can realize the mapping from the system state to PID parameters, while the Critic evaluates the outputs of the Actor and produces TD error. Based on TD error performance index and gradient descent method, the updating rules of RBF kernel function and network weights were given. Simulation results show that the proposed controller is efficient for complex nonlinear systems and it is perfectly adaptable and strongly robust, which is better than that of a conventional PID controller.
Bonesini, M
2008-01-01
The international Muon Ionization Cooling Experiment (MICE) will carry out a systematic investigation of ionization cooling of a muon beam. As the emittance measurement will be done on a particle-by-particle basis, sophisticated beam instrumentation is needed to measure particle coordinates and timing vs RF. A PID system based on three time-of-flight stations, two Aerogel Cerenkov detectors and a KLOE-like calorimeter has been constructed in order to keep beam contamination ($e, \\pi$) well below 1%. The MICE time-of-flight system will measure timing with a resolution better than 70 ps per plane, in a harsh environment due to high particle rates, fringe magnetic fields and electron backgrounds from RF dark current.
Design and implementation of a 2-DOF PID compensation for magnetic levitation systems.
Ghosh, Arun; Rakesh Krishnan, T; Tejaswy, Pailla; Mandal, Abhisek; Pradhan, Jatin K; Ranasingh, Subhakant
2014-07-01
This paper employs a 2-DOF (degree of freedom) PID controller for compensating a physical magnetic levitation system. It is shown that because of having a feedforward gain in the proposed 2-DOF PID control, the transient performance of the compensated system can be changed in a desired manner unlike the conventional 1-DOF PID control. It is also shown that for a choice of PID parameters, although the theoretical loop robustness is the same for both the compensated systems, in real-time, 2-DOF PID control may provide superior robustness if a suitable choice of the feedforward parameter is made. The results are verified through simulations and experiments. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.
Lefèvre, T; Chauvin, P
2015-02-01
In an epidemiologist's toolbox, three main types of statistical tools can be found: means and proportions comparisons, linear or logistic regression models and Cox-type regression models. All these techniques have their own multivariate formulations, so that biases can be accounted for. Nonetheless, there is an entire set of natively massive multivariate techniques, which are based on weaker assumptions than classical statistical techniques are, and which seem to be underestimated or remain unknown to most epidemiologists. These techniques are used for pattern recognition or clustering – that is, for retrieving homogeneous groups in data without any a priori about these groups. They are widely used in connex domains such as genetics or biomolecular studies. Most clustering techniques require tuning specific parameters so that groups can be identified in data. A critical parameter to set is the number of groups the technique needs to discover. Different approaches to find the optimal number of groups are available, such as the silhouette approach and the robustness approach. This article presents the key aspects of clustering techniques (how proximity between observations is defined and how to find the number of groups), two archetypal techniques (namely the k-means and PAM algorithms) and how they relate to more classical statistical approaches. Through a theoretical, simple example and a real data application, we provide a complete framework within which classical epidemiological concerns can be reconsidered. We show how to (i) identify whether distinct groups exist in data, (ii) identify the optimal number of groups in data, (iii) label each observation according to its own group and (iv) analyze the groups identified according to separate and explicative data. In addition, how to achieve consistent results while removing sensitivity to initial conditions is explained. Clustering techniques, in conjunction with methods for parameter tuning, provide the
PID1 (NYGGF4), a new growth-inhibitory gene in embryonal brain tumors and gliomas.
Erdreich-Epstein, Anat; Robison, Nathan; Ren, Xiuhai; Zhou, Hong; Xu, Jingying; Davidson, Tom B; Schur, Mathew; Gilles, Floyd H; Ji, Lingyun; Malvar, Jemily; Shackleford, Gregory M; Margol, Ashley S; Krieger, Mark D; Judkins, Alexander R; Jones, David T W; Pfister, Stefan M; Kool, Marcel; Sposto, Richard; Asgharzadeh, Shahab; Asgharazadeh, Shahab
2014-02-15
We present here the first report of PID1 (Phosphotyrosine Interaction Domain containing 1; NYGGF4) in cancer. PID1 was identified in 2006 as a gene that modulates insulin signaling and mitochondrial function in adipocytes and muscle cells. Using four independent medulloblastoma datasets, we show that mean PID1 mRNA levels were lower in unfavorable medulloblastomas (groups 3 and 4, and anaplastic histology) compared with favorable medulloblastomas (SHH and WNT groups, and desmoplastic/nodular histology) and with fetal cerebellum. In two large independent glioma datasets, PID1 mRNA was lower in glioblastomas (GBM), the most malignant gliomas, compared with other astrocytomas, oligodendrogliomas and nontumor brains. Neural and proneural GBM subtypes had higher PID1 mRNA compared with classical and mesenchymal GBM. Importantly, overall survival and radiation-free progression-free survival were longer in medulloblastoma patients whose tumors had higher PID1 mRNA (univariate and multivariate analyses). Higher PID1 mRNA also correlated with longer overall survival in patients with glioma and GBM. In cell culture, overexpression of PID1 inhibited colony formation in medulloblastoma, atypical teratoid rhabdoid tumor (ATRT), and GBM cell lines. Increasing PID1 also increased cell death and apoptosis, inhibited proliferation, induced mitochondrial depolaization, and decreased serum-mediated phosphorylation of AKT and ERK in medulloblastoma, ATRT, and/or GBM cell lines, whereas siRNA to PID1 diminished mitochondrial depolarization. These data are the first to link PID1 to cancer and suggest that PID1 may have a tumor inhibitory function in these pediatric and adult brain tumors. ©2013 AACR
Application of Improved Genetic Algorithm in PID Controller Parameters Optimization
Directory of Open Access Journals (Sweden)
Ying Chen
2013-01-01
Full Text Available Ying Chen, Yong-jie Ma, Wen-xia Yun College of Physics and Electronic Engineering, Northwest Normal University, Anning Road no.967 ,Lanzhou,China,0931-7971503 e-mail:chenying1386685@126.com Abstract The setting and optimization of Proportion Integration Differentiation(PID parameters have been always the important study topics in the automatic control field. The current optimization design methods are often difficult to consider the system requirements for quickness ,reliability and robustness .So a method of PID controller parameters optimization based on Improved Genetic Algorithm(IGA is presented .Simulations with Matlab have proved that the control performance index based on IGA is better than that of the GA method and Z-N method, and is a method which has good practical value of the PID parameter setting and optimization .
Mutation particle swarm optimization of the BP-PID controller for piezoelectric ceramics
Zheng, Huaqing; Jiang, Minlan
2016-01-01
PID control is the most common used method in industrial control because its structure is simple and it is easy to implement. PID controller has good control effect, now it has been widely used. However, PID method has a few limitations. The overshoot of the PID controller is very big. The adjustment time is long. When the parameters of controlled plant are changing over time, the parameters of controller could hardly change automatically to adjust to changing environment. Thus, it can't meet the demand of control quality in the process of controlling piezoelectric ceramic. In order to effectively control the piezoelectric ceramic and improve the control accuracy, this paper replaced the learning algorithm of the BP with the mutation particle swarm optimization algorithm(MPSO) on the process of the parameters setting of BP-PID. That designed a better self-adaptive controller which is combing the BP neural network based on mutation particle swarm optimization with the conventional PID control theory. This combination is called the MPSO-BP-PID. In the mechanism of the MPSO, the mutation operation is carried out with the fitness variance and the global best fitness value as the standard. That can overcome the precocious of the PSO and strengthen its global search ability. As a result, the MPSO-BP-PID can complete controlling the controlled plant with higher speed and accuracy. Therefore, the MPSO-BP-PID is applied to the piezoelectric ceramic. It can effectively overcome the hysteresis, nonlinearity of the piezoelectric ceramic. In the experiment, compared with BP-PID and PSO-BP-PID, it proved that MPSO is effective and the MPSO-BP-PID has stronger adaptability and robustness.
Directory of Open Access Journals (Sweden)
Endra Joelianto
2009-11-01
Full Text Available The well known PID controller has inherent limitations in fulfilling simultaneously the conflicting control design objectives. Parameters of the tuned PID controller should trade off the requirement of tracking set-point performances, disturbance rejection and stability robustness. Combination of hybrid reference control (HRC with PID controller results in the transient response performances can be independently achieved without deteriorating the disturbance rejection properties and the stability robustness requirement. This paper proposes a fuzzy based HRC where the membership functions of the fuzzy logic system are obtained by using a substractive clustering technique. The proposed method guarantees the transient response performances satisfaction while preserving the stability robustness of the closed loop system controlled by the PID controller with effective and systematic procedures in designing the fuzzy hybrid reference control system.
Design New Intelligent PID like Fuzzy Backstepping Controller
Directory of Open Access Journals (Sweden)
Arzhang Khajeh
2014-02-01
Full Text Available The minimum rule base Proportional Integral Derivative (PID Fuzzy backstepping Controller is presented in this research. The popularity of PID Fuzzy backstepping controller can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID Fuzzy backstepping controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing. PID methodology has three inputs and if any input is described with seven linguistic values, and any rule has three conditions we will need 7 × 7 × 7 = 343 rules. It is too much work to write 343 rules. In this research the PID-like fuzzy controller can be constructed as a parallel structure of a PD-like fuzzy controller and a PI-like controller to have the minimum rule base. However backstepping controller is work based on cancelling decoupling and nonlinear terms of dynamic parameters of each link, this controller is work based on manipulator dynamic model and this technique is highly sensitive to the knowledge of all parameters of nonlinear robot manipulator’s dynamic equation. This research is used to reduce or eliminate the backstepping controller problem based on minimum rule base fuzzy logic theory to control of flexible robot manipulator system and testing of the quality of process control in the simulation environment of MATLAB/SIMULINK Simulator.
PID Tuning Using Extremum Seeking
Energy Technology Data Exchange (ETDEWEB)
Killingsworth, N; Krstic, M
2005-11-15
Although proportional-integral-derivative (PID) controllers are widely used in the process industry, their effectiveness is often limited due to poor tuning. Manual tuning of PID controllers, which requires optimization of three parameters, is a time-consuming task. To remedy this difficulty, much effort has been invested in developing systematic tuning methods. Many of these methods rely on knowledge of the plant model or require special experiments to identify a suitable plant model. Reviews of these methods are given in [1] and the survey paper [2]. However, in many situations a plant model is not known, and it is not desirable to open the process loop for system identification. Thus a method for tuning PID parameters within a closed-loop setting is advantageous. In relay feedback tuning [3]-[5], the feedback controller is temporarily replaced by a relay. Relay feedback causes most systems to oscillate, thus determining one point on the Nyquist diagram. Based on the location of this point, PID parameters can be chosen to give the closed-loop system a desired phase and gain margin. An alternative tuning method, which does not require either a modification of the system or a system model, is unfalsified control [6], [7]. This method uses input-output data to determine whether a set of PID parameters meets performance specifications. An adaptive algorithm is used to update the PID controller based on whether or not the controller falsifies a given criterion. The method requires a finite set of candidate PID controllers that must be initially specified [6]. Unfalsified control for an infinite set of PID controllers has been developed in [7]; this approach requires a carefully chosen input signal [8]. Yet another model-free PID tuning method that does not require opening of the loop is iterative feedback tuning (IFT). IFT iteratively optimizes the controller parameters with respect to a cost function derived from the output signal of the closed-loop system, see [9
Active Queue Management in TCP Networks Based on Fuzzy-Pid Controller
Directory of Open Access Journals (Sweden)
Hossein ASHTIANI
2012-01-01
Full Text Available We introduce a novel and robust active queue management (AQM scheme based on a fuzzy controller, called hybrid fuzzy-PID controller. In the TCP network, AQM is important to regulate the queue length by passing or dropping the packets at the intermediate routers. RED, PI, and PID algorithms have been used for AQM. But these algorithms show weaknesses in the detection and control of congestion under dynamically changing network situations. In this paper a novel Fuzzy-based proportional-integral derivative (PID controller, which acts as an active queue manager (AQM for Internet routers, is proposed. These controllers are used to reduce packet loss and improve network utilization in TCP/IP networks. A new hybrid controller is proposed and compared with traditional RED based controller. Simulations are carried out to demonstrate the effectiveness of the proposed method and show that, the new hybrid fuzzy PID controller provides better performance than random early detection (RED and PID controllers
Directory of Open Access Journals (Sweden)
REZAZADEH, A.
2010-05-01
Full Text Available Nonlinear characteristics of wind turbines and electric generators necessitate complicated and nonlinear control of grid connected Wind Energy Conversion Systems (WECS. This paper proposes a modified self-tuning PID control strategy, using reinforcement learning for WECS control. The controller employs Actor-Critic learning in order to tune PID parameters adaptively. These Actor-Critic learning is a special kind of reinforcement learning that uses a single wavelet neural network to approximate the policy function of the Actor and the value function of the Critic simultaneously. These controllers are used to control a typical WECS in noiseless and noisy condition and results are compared with an adaptive Radial Basis Function (RBF PID control based on reinforcement learning and conventional PID control. Practical emulated results prove the capability and the robustness of the suggested controller versus the other PID controllers to control of the WECS. The ability of presented controller is tested by experimental setup.
Intelligent particle swarm optimized fuzzy PID controller for AVR system
Energy Technology Data Exchange (ETDEWEB)
Mukherjee, V. [Department of Electrical Engineering, Asansol Engineering College, Asansol, West Bengal (India); Ghoshal, S.P. [Department of Electrical Engineering, National Institute of Technology, Durgapur, West Bengal (India)
2007-10-15
In process plants like thermal power plants, biomedical instrumentation the popular use of proportional-integral-derivative (PID) controllers can be noted. Proper tuning of such controllers is obviously a prime priority as any other alternative situation will require a high degree of industrial expertise. So in order to get the best results of PID controllers the optimal tuning of PID gains is required. This paper, thus, deals with the determination of off-line, nominal, optimal PID gains of a PID controller of an automatic voltage regulator (AVR) for nominal system parameters and step reference voltage input. Craziness based particle swarm optimization (CRPSO) and binary coded genetic algorithm (GA) are the two props used to get the optimal PID gains. CRPSO proves to be more robust than GA in performing optimal transient performance even under various nominal operating conditions. Computational time required by CRPSO is lesser than that of GA. Factors that have influenced the enhancement of global searching ability of PSO are the incorporation of systematic and intelligent velocity, position updating procedure and introduction of craziness. This modified from of PSO is termed as CRPSO. For on-line off-nominal system parameters Sugeno fuzzy logic (SFL) is applied to get on-line terminal voltage response. The work of SFL is to extrapolate intelligently and linearly, the nominal optimal gains in order to determine off-nominal optimal gains. The on-line computational burden of SFL is noticeably low. Consequently, on-line optimized transient response of incremental change in terminal voltage is obtained. (author)
Pelvic Inflammatory Disease (PID) Treatment and Care
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Design of PID controller with incomplete derivation based on differential evolution algorithm
Institute of Scientific and Technical Information of China (English)
Wu Lianghong; Wang Yaonan; Zhou Shaowu; Tan Wen
2008-01-01
To determine the optimal or near optimal parameters of PID controller with incomplete derivation, a novel design method based on differential evolution (DE) algorithm is presented. The controller is called DE-PID controller. To overcome the disadvantages of the integral performance criteria in the frequency domain such as IAE, ISE, and ITSE, a new performance criterion in the time domain is proposed. The optimization procedures employing the DE algorithm to search the optimal or near optimal PID controller parameters of a control system are demonstrated in detail. Three typical control systems are chosen to test and evaluate the adaptation and robustness of the proposed DE-PID controller. The simulation results show that the proposed approach has superior features of easy implementation, stable convergence characteristic, and good computational efficiency. Compared with the ZN, GA, and ASA, the proposed design method is indeed more efficient and robust in improving the step response of a control system.
New Asymmetric Fuzzy PID Control for Pneumatic Position Control System
Institute of Scientific and Technical Information of China (English)
薛阳; 彭光正; 范萌; 伍清河
2004-01-01
A fuzzy control algorithm of asymmetric fuzzy strategy is introduced for a servo-pneumatic position system. It can effectively solve the difficult problems of single rod low friction cylinders, which are mainly caused by asymmetric structures and different friction characteristics in two directions. On the basis of this algorithm, a traditional PID control is used to improve dynamic performance. Furthermore, a new asymmetric fuzzy PID control with α factor is advanced to improve the self-adaptability and robustness of the system. Both the theoretical analyses and experimental results prove that, with this control strategy, the dynamic performance of the system can be greatly improved. The system using this control algorithm has strong robustness and it obtains desired overshoot and repeatability in both transient and steady-state responses.
A SURVEY: PID OPTIMIZATION FOR AUTOMATIC VOLTAGE REGULATOR
Ajay Dixit*, Miss.Pragati Joshi, Mr.Mahesh Lokhande
2016-01-01
This paper presents on survey paper of PSO and automatic voltage regulator for synchronous generator. It is used to obtain for regulation and stability of any electrical equipment. There are many technology/methods were used in automatic voltage regulator as well as different controller used for improving robustness, overshoot, rise time and voltage control but problem is about to survey on Automatic Voltage Regulator. Comparisons studies which are based on PID Controller are performed to sh...
Simulation and Tuning of PID Controllers using Evolutionary Algorithms
Directory of Open Access Journals (Sweden)
K.R.S. Narayanan
2012-10-01
Full Text Available The Proportional Integral Derivative (PID controller is the most widely used control strategy in the Industry. The popularity of PID controllers can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing. Biologically inspired evolutionary strategies have gained importance over other strategies because of their consistent performance over wide range of process models and their flexibility. The level control systems on Deaerator, Feed Water Heaters, and Condenser Hot well are critical to the proper operation of the units in Nuclear Power plants. For Precise control of level, available tuning technologies based on conventional optimization methods are found to be inadequate as these conventional methods are having limitations. To overcome the limitations, alternate tuning techniques based on Genetic Algorithm are emerging. This paper analyses the manual tuning techniques and compares the same with Genetic Algorithm tuning methods for tuning PID controllers for level control system and testing of the quality of process control in the simulation environment of PFBR Operator Training Simulator(OTS.
Performance assessment of PID and IMC tuning methods for a mixing process with time delay.
Selvi, J Arputha Vijaya; Radhakrishnan, T K; Sundaram, S
2007-06-01
A flow process with time delay has been considered for modeling and control. A dilute solution of sodium chloride is used as tracer and an online conductivity measurement unit as sensor and recorder. The objective of the current study is to design control algorithms and present corresponding robust control analysis for the process. The control methodologies considered are (i) conventional PID control and (ii) internal model control (IMC). The control structures are comparatively analyzed using standard robustness measures for stability and performance. Of the two control algorithms, conventional PID and IMC, IMC exhibits faster settling time, no overshoot, better set-point tracking and disturbance rejection, and good robust performance than the PID control scheme.
Institute of Scientific and Technical Information of China (English)
施惠元; 苏成利; 曹江涛; 李平; 宋英莉; 李宁波
2015-01-01
The control of gas fractionation unit (GFU) in petroleum industry is very difficult due to multivariable characteristics and a large time delay. PID controllers are still applied in most industry processes. However, the traditional PID control has been proven not sufficient and capable for this particular petro-chemical process. In this work, an incremental multivariable predictive functional control (IMPFC) algorithm was proposed with less online computation, great precision and fast response. An incremental transfer function matrix model was set up through the step-response data, and predictive outputs were deduced with the theory of single-value optimization. The results show that the method can optimize the incremental control variable and reject the constraint of the incremental control variable with the positional predictive functional control algorithm, and thereby making the control variable smoother. The predictive output error and future set-point were approximated by a polynomial, which can overcome the problem under the model mismatch and make the predictive outputs track the reference trajectory. Then, the design of incremental multivariable predictive functional control was studied. Simulation and application results show that the proposed control strategy is effective and feasible to improve control performance and robustness of process.
Design a Novel SISO Off-line Tuning of Modified PID Fuzzy Sliding Mode Controller
Directory of Open Access Journals (Sweden)
Ali Shahcheraghi
2014-01-01
Full Text Available The Proportional Integral Derivative (PID Fuzzy Sliding Mode Controller (FSMC is the most widely used control strategy in the Industry (control of robotic arm. The popularity of PID FSMC controllers can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID FSMC controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing. Biologically inspired evolutionary strategies have gained importance over other strategies because of their consistent performance over wide range of process models and their flexibility. This paper analyses the modified PID FSMC controllers based on minimum rule base for flexible robot manipulator system and test the quality of process control in the simulation environment of MATLAB/SIMULINK Simulator.
Design of sewage treatment system by applying fuzzy adaptive PID controller
Jin, Liang-Ping; Li, Hong-Chan
2013-03-01
In the sewage treatment system, the dissolved oxygen concentration control, due to its nonlinear, time-varying, large time delay and uncertainty, is difficult to establish the exact mathematical model. While the conventional PID controller only works with good linear not far from its operating point, it is difficult to realize the system control when the operating point far off. In order to solve the above problems, the paper proposed a method which combine fuzzy control with PID methods and designed a fuzzy adaptive PID controller based on S7-300 PLC .It employs fuzzy inference method to achieve the online tuning for PID parameters. The control algorithm by simulation and practical application show that the system has stronger robustness and better adaptability.
Stabilization and PID tuning algorithms for second-order unstable processes with time-delays.
Seer, Qiu Han; Nandong, Jobrun
2017-03-01
Open-loop unstable systems with time-delays are often encountered in process industry, which are often more difficult to control than stable processes. In this paper, the stabilization by PID controller of second-order unstable processes, which can be represented as second-order deadtime with an unstable pole (SODUP) and second-order deadtime with two unstable poles (SODTUP), is performed via the necessary and sufficient criteria of Routh-Hurwitz stability analysis. The stability analysis provides improved understanding on the existence of a stabilizing range of each PID parameter. Three simple PID tuning algorithms are proposed to provide desired closed-loop performance-robustness within the stable regions of controller parameters obtained via the stability analysis. The proposed PID controllers show improved performance over those derived via some existing methods.
Series pid pitch controller of large wind turbines generator
Directory of Open Access Journals (Sweden)
Micić Aleksandar D.
2015-01-01
Full Text Available For this stable process with oscillatory dynamics, characterized with small damping ratio and dominant transport delay, design of the series PID pitch controller is based on the model obtained from the open-loop process step response, filtered with the second-order Butterworth filter Fbw. Performance of the series PID pitch controller, with the filter Fbw, is analyzed by simulations of the set-point and input/output disturbance responses, including simulations with a colored noise added to the control variable. Excellent performance/robustness tradeoff is obtained, compared to the recently proposed PI pitch controllers and to the modified internal model pitch controller, developed here, which has a natural mechanism to compensate effect of dominant transport delay. [Projekat Ministarstva nauke Republike Srbije, br. III 47016
A closed-loop particle swarm optimizer for multivariable process controller design
Institute of Scientific and Technical Information of China (English)
Kai HAN; Jun ZHAO; Zu-hua XU; Ji-xin QIAN
2008-01-01
Design of general multivariable process controllers is an attractive and practical alternative to optimizing design by evolutionary algorithms (EAs) since it can be formulated as an optimization problem.A closed-loop particle swarm optimization (CLPSO) algorithm is proposed by mapping PSO elements into the closed-loop system based on control theories.At each time step,a proportional integral (PI) controller is used to calculate an updated inertia weight for each particle in swarms from its last fitness.With this modification,limitations caused by a uniform inertia weight for the whole population are avoided,and the particles have enough diversity.After the effectiveness,efficiency and robustness are tested by benchmark functions,CLPSO is applied to design a multivariable proportional-integral-derivative (PID) controller for a solvent dehydration tower in a chemical plant and has improved its performances.
Chen, Peiying; Zhang, Weidong
2007-04-01
This paper improves an inverted decoupling technique for a class of stable linear multivariable processes with multiple time delays and nonminimum-phase zeros. Two decoupling schemes are proposed based on the inverted decoupling technique. One is a developed inverted decoupling scheme. In this scheme, the decoupler is designed such that the inverted decoupling technique accommodates a wider field than the one introduced in the published literature. However, due to the stability issue, some multivariable processes still cannot be decoupled by the inverted decoupling structure. To solve this problem, another modified decoupling scheme with unity feedback structure is suggested for implementation. The Internal Model Control (IMC) theory is applied here to design PI/PID controllers for the decoupled processes. Furthermore, in the presence of multiplicative input uncertainty, low bounds of the control parameters are derived quantitatively for guaranteeing robust stability of the system. Simulations are illustrated for demonstrating the validity of the proposed control schemes.
Zhang, Shu; Taft, Cyrus W; Bentsman, Joseph; Hussey, Aaron; Petrus, Bryan
2012-09-01
Tuning a complex multi-loop PID based control system requires considerable experience. In today's power industry the number of available qualified tuners is dwindling and there is a great need for better tuning tools to maintain and improve the performance of complex multivariable processes. Multi-loop PID tuning is the procedure for the online tuning of a cluster of PID controllers operating in a closed loop with a multivariable process. This paper presents the first application of the simultaneous tuning technique to the multi-input-multi-output (MIMO) PID based nonlinear controller in the power plant control context, with the closed-loop system consisting of a MIMO nonlinear boiler/turbine model and a nonlinear cluster of six PID-type controllers. Although simplified, the dynamics and cross-coupling of the process and the PID cluster are similar to those used in a real power plant. The particular technique selected, iterative feedback tuning (IFT), utilizes the linearized version of the PID cluster for signal conditioning, but the data collection and tuning is carried out on the full nonlinear closed-loop system. Based on the figure of merit for the control system performance, the IFT is shown to deliver performance favorably comparable to that attained through the empirical tuning carried out by an experienced control engineer.
A novel optimal PID plus second order derivative controller for AVR system
Directory of Open Access Journals (Sweden)
Mouayad A. Sahib
2015-06-01
Full Text Available This paper proposes a novel controller for automatic voltage regulator (AVR system. The controller is a four term control type consisting of proportional, integral, derivative, and second order derivative terms (PIDD2. The four parameters of the proposed controller are optimized using particle swarm optimization (PSO algorithm. The performance of the proposed PIDD2 is compared with various PID controllers tuned by modern heuristic optimization algorithms. In addition, a comparison with the fractional order PID (FOPID controller tuned by Chaotic Ant Swarm (CAS algorithm is also performed. Furthermore, a frequency response, zero-pole map, and robustness analysis of the AVR system with PIDD2 is performed. Practical implementation issues of the proposed controller are also addressed. Simulation results showed a superior response performance of the PIDD2 controller in comparison to PID and FOPID controllers. Moreover, the proposed PIDD2 can highly improve the system robustness with respect to model uncertainties.
Pelvic Inflammatory Disease (PID) Fact Sheet
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Rail Vehicle Vibrations Control Using Parameters Adaptive PID Controller
Directory of Open Access Journals (Sweden)
Muzaffer Metin
2014-01-01
Full Text Available In this study, vertical rail vehicle vibrations are controlled by the use of conventional PID and parameters which are adaptive to PID controllers. A parameters adaptive PID controller is designed to improve the passenger comfort by intuitional usage of this method that renews the parameters online and sensitively under variable track inputs. Sinusoidal vertical rail misalignment and measured real rail irregularity are considered as two different disruptive effects of the system. Active vibration control is applied to the system through the secondary suspension. The active suspension application of rail vehicle is examined by using 5-DOF quarter-rail vehicle model by using Manchester benchmark dynamic parameters. The new parameters of adaptive controller are optimized by means of genetic algorithm toolbox of MATLAB. Simulations are performed at maximum urban transportation speed (90 km/h of the rail vehicle with ±5% load changes of rail vehicle body to test the robustness of controllers. As a result, superior performance of parameters of adaptive controller is determined in time and frequency domain.
Comparison of intelligent fuzzy based AGC coordinated PID controlled and PSS controlled AVR system
Energy Technology Data Exchange (ETDEWEB)
Mukherjee, V. [Department of Electrical Engineering, Asansol Engineering College, Asansol, West Bengal (India); Ghoshal, S.P. [Department of Electrical Engineering, National Institute of Technology, Durgapur, West Bengal (India)
2007-11-15
This paper attempts to investigate the performance of intelligent fuzzy based coordinated control of the Automatic Generation Control (AGC) loop and the excitation loop equipped with Proportional Integral Derivative (PID) controlled Automatic Voltage Regulator (AVR) system and Power System Stabilizer (PSS) controlled AVR system. The work establishes that PSS controlled AVR system is much more robust in dynamic performance of the system over a wide range of system operating configurations. Thus, it is revealed that PSS equipped AVR is much more superior than PID equipped AVR in damping the oscillation resulting in improved transient response. The paper utilizes a novel class of Particle Swarm Optimization (PSO) termed as Craziness based Particle Swarm Optimization (CRPSO) as optimizing tool to get optimal tuning of PSS parameters as well as the gains of PID controllers. For on-line, off-nominal operating conditions Takagi Sugeno Fuzzy Logic (TSFL) has been applied to obtain the off-nominal optimal gains of PID controllers and parameters of PSS. Implementation of TSFL helps to achieve very fast dynamic response. Fourth order model of generator with AVR and high gain thyristor excitation system is considered for PSS controlled system while normal gain exciter is considered for PID controlled system. Simulation study also reveals that with high gain exciter, PID control is not at all effective. Transient responses are achieved by using modal analysis. (author)
A Method for Precision Closed-Loop Irrigation Using a Modified PID Control Algorithm
Goodchild, Martin; Kühn, Karl; Jenkins, Malcolm; Burek, Kazimierz; Dutton, Andrew
2016-04-01
The benefits of closed-loop irrigation control have been demonstrated in grower trials which show the potential for improved crop yields and resource usage. Managing water use by controlling irrigation in response to soil moisture changes to meet crop water demands is a popular approach but requires knowledge of closed-loop control practice. In theory, to obtain precise closed-loop control of a system it is necessary to characterise every component in the control loop to derive the appropriate controller parameters, i.e. proportional, integral & derivative (PID) parameters in a classic PID controller. In practice this is often difficult to achieve. Empirical methods are employed to estimate the PID parameters by observing how the system performs under open-loop conditions. In this paper we present a modified PID controller, with a constrained integral function, that delivers excellent regulation of soil moisture by supplying the appropriate amount of water to meet the needs of the plant during the diurnal cycle. Furthermore, the modified PID controller responds quickly to changes in environmental conditions, including rainfall events which can result in: controller windup, under-watering and plant stress conditions. The experimental work successfully demonstrates the functionality of a constrained integral PID controller that delivers robust and precise irrigation control. Coir substrate strawberry growing trial data is also presented illustrating soil moisture control and the ability to match water deliver to solar radiation.
A novel auto-tuning PID control mechanism for nonlinear systems.
Cetin, Meric; Iplikci, Serdar
2015-09-01
In this paper, a novel Runge-Kutta (RK) discretization-based model-predictive auto-tuning proportional-integral-derivative controller (RK-PID) is introduced for the control of continuous-time nonlinear systems. The parameters of the PID controller are tuned using RK model of the system through prediction error-square minimization where the predicted information of tracking error provides an enhanced tuning of the parameters. Based on the model-predictive control (MPC) approach, the proposed mechanism provides necessary PID parameter adaptations while generating additive correction terms to assist the initially inadequate PID controller. Efficiency of the proposed mechanism has been tested on two experimental real-time systems: an unstable single-input single-output (SISO) nonlinear magnetic-levitation system and a nonlinear multi-input multi-output (MIMO) liquid-level system. RK-PID has been compared to standard PID, standard nonlinear MPC (NMPC), RK-MPC and conventional sliding-mode control (SMC) methods in terms of control performance, robustness, computational complexity and design issue. The proposed mechanism exhibits acceptable tuning and control performance with very small steady-state tracking errors, and provides very short settling time for parameter convergence.
Direct Drive Electro-hydraulic Servo Control System Design with Self-Tuning Fuzzy PID Controller
Directory of Open Access Journals (Sweden)
Wang Yeqin
2013-06-01
Full Text Available According to the nonlinear and time-varying uncertainty characteristics of direct drive electro-hydraulic servo control system, a self-tuning fuzzy PID control method with speed change integral and differential ahead optimizing operator is put forward by combining fuzzy inference and traditional PID control in this paper.The rule of fuzzy logic is designed, the membership function of the fuzzy subsets is determined and lookup table method is used to correcte the PID parameters in real-time. Finally the simulation is conducted with the typical input signal, such as tracking step, sine etc. The simulation results show that，the self-tuning fuzzy PID control system can effectively improve the dynamic characteristic when the system is out of the range of the operating point compared with the traditional PID control system, there is obvious improvement in the indexes of rapidity, stability and accuracy, and fuzzy self-tuning PID Control is more robust, and more suitable for direct drive electro-hydraulic servo system.
Institute of Scientific and Technical Information of China (English)
谭冠政; 李安平
2003-01-01
An optimal PID controller with incomplete derivation is proposed based on fuzzy inference and the geneticalgorithm, which is called the fuzzy-GA PID controller with incomplete derivation. It consists of the off-line part andthe on-line part. In the off-line part, by taking the overshoot, rise time, and settling time of system unit step re-sponse as the performance indexes and by using the genetic algorithm, a group of optimal PID parameters K*p , Ti* ,and Tj are obtained, which are used as the initial values for the on-line tuning of PID parameters. In the on-linepart, based on K; , Ti* , and T*d and according to the current system error e and its time derivative, a dedicatedprogram is written, which is used to optimize and adjust the PID parameters on line through a fuzzy inference mech-anism to ensure that the system response has optimal dynamic and steady-state performance. The controller has beenused to control the D. C. motor of the intelligent bionic artificial leg designed by the authors. The result of computersimulation shows that this kind of optimal PID controller has excellent control performance and robust performance.
Dexter, Alex; Race, Alan M; Styles, Iain B; Bunch, Josephine
2016-11-15
Spatial clustering is a powerful tool in mass spectrometry imaging (MSI) and has been demonstrated to be capable of differentiating tumor types, visualizing intratumor heterogeneity, and segmenting anatomical structures. Several clustering methods have been applied to mass spectrometry imaging data, but a principled comparison and evaluation of different clustering techniques presents a significant challenge. We propose that testing whether the data has a multivariate normal distribution within clusters can be used to evaluate the performance when using algorithms that assume normality in the data, such as k-means clustering. In cases where clustering has been performed using the cosine distance, conversion of the data to polar coordinates prior to normality testing should be performed to ensure normality is tested in the correct coordinate system. In addition to these evaluations of internal consistency, we demonstrate that the multivariate normal distribution can then be used as a basis for statistical modeling of MSI data. This allows the generation of synthetic MSI data sets with known ground truth, providing a means of external clustering evaluation. To demonstrate this, reference data from seven anatomical regions of an MSI image of a coronal section of mouse brain were modeled. From this, a set of synthetic data based on this model was generated. Results of r(2) fitting of the chi-squared quantile-quantile plots on the seven anatomical regions confirmed that the data acquired from each spatial region was found to be closer to normally distributed in polar space than in Euclidean. Finally, principal component analysis was applied to a single data set that included synthetic and real data. No significant differences were found between the two data types, indicating the suitability of these methods for generating realistic synthetic data.
Directory of Open Access Journals (Sweden)
D. RAMA REDDY
2012-07-01
Full Text Available This paper describes the stability regions of PID (Proportional +Integral+ Derivative and a new PID with series leading correction (SLC for Networked control system with time delay. The new PID controller has a tuning parameter ‘β’. The relation between β, KP, KI and KD is derived. The effect of plant parameters on stabilityregion of PID controllers and SLC-PID controllers in first-order and second-order systems with time delay are also studied. Finally, an open-loop zero was inserted into the plant-unstable second order system with time delay so that the stability regions of PID and SLC-PID controllers get effectively enlarged. The total system isimplemented using MATLAB/Simulink.
Directory of Open Access Journals (Sweden)
C.Agees Kumar
2010-07-01
Full Text Available PID controller is widely used for main steam temperature control of boiler unit in thermal power plant. To avoid the drawback of current PID design methods, this paper presents a new design method for multi-objective PID controller to synthetically consider system requirement in reliability and robustness. Adaptive weighted PSO (AWPSO technique is applied to the parameter optimization design. The optimization problem considered is highly nonlinear, complex, with multiple objectives and constraints. The simulation results on an actual main steam temperature control system indicate that, the multi-objective PID controller designed by presented method, can improve the dynamic performance of main steam temperature control system, with good robustness ability.
New tuning method for PID controller.
Shen, Jing-Chung
2002-10-01
In this paper, a tuning method for proportional-integral-derivative (PID) controller and the performance assessment formulas for this method are proposed. This tuning method is based on a genetic algorithm based PID controller design method. For deriving the tuning formula, the genetic algorithm based design method is applied to design PID controllers for a variety of processes. The relationship between the controller parameters and the parameters that characterize the process dynamics are determined and the tuning formula is then derived. Using simulation studies, the rules for assessing the performance of a PID controller tuned by the proposed method are also given. This makes it possible to incorporate the capability to determine if the PID controller is well tuned or not into an autotuner. An autotuner based on this new tuning method and the corresponding performance assessment rules is also established. Simulations and real-time experimental results are given to demonstrate the effectiveness and usefulness of these formulas.
COMMANDE PID DES SYSTÈMES À RETARD
Farkh, Rihem
2011-01-01
This thesis is dedicated to PID controllers stabilization for a stable first and second-order delay system. The Generalized Kharitonov Theorem for quasi-polynomials is exploited for the purpose of synthesizing a robust controller that stabilize a given interval plant family with knowing time delay. Finally the genetic algorithm is proposed to determine optimum controllers using one of the following criterion ISE, IAE, ITAE and ITSE.; Ce mémoire est dédié à la caractérisation de contrôleurs PI...
DEFF Research Database (Denmark)
Barndorff-Nielsen, Ole Eiler; Hansen, Peter Reinhard; Lunde, Asger
2011-01-01
We propose a multivariate realised kernel to estimate the ex-post covariation of log-prices. We show this new consistent estimator is guaranteed to be positive semi-definite and is robust to measurement error of certain types and can also handle non-synchronous trading. It is the first estimator...
Institute of Scientific and Technical Information of China (English)
Chen,Guochu; Zhang,Lin; Hao,Ninmei; Liu,Xianguang; Wang,Junhong
2003-01-01
Guided by the principle of neural network, an intelligent PID controller based on neural network is devised and applied to control of constant temperature and constant liquidlevel system. The experiment results show that this controller has high accuracy and strong robustness and good characters.
Directory of Open Access Journals (Sweden)
Wilmar Hernandez
2005-11-01
Full Text Available In the present paper, in order to estimate the response of both a wheel speedsensor and an accelerometer placed in a car under performance tests, robust and optimalmultivariable estimation techniques are used. In this case, the disturbances and noisescorrupting the relevant information coming from the sensorsÃ¢Â€Â™ outputs are so dangerous thattheir negative influence on the electrical systems impoverish the general performance of thecar. In short, the solution to this problem is a safety related problem that deserves our fullattention. Therefore, in order to diminish the negative effects of the disturbances and noiseson the carÃ¢Â€Â™s electrical and electromechanical systems, an optimum observer is used. Theexperimental results show a satisfactory improvement in the signal-to-noise ratio of therelevant signals and demonstrate the importance of the fusion of several intelligent sensordesign techniques when designing the intelligent sensors that todayÃ¢Â€Â™s cars need.
Application of Adaptive Fuzzy PID Leveling Controller
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Ke Zhang
2013-05-01
Full Text Available Aiming at the levelling precision, speed and stability of suspended access platform, this paper put forward a new adaptive fuzzy PID control levelling algorithm by fuzzy theory. The method is aided design by using the SIMULINK toolbox of MATLAB, and setting the membership function and the fuzzy-PID control rule. The levelling algorithm can real-time adjust the three parameters of PID according to the fuzzy rules due to the current state. It is experimented, which is verified the algorithm have better stability and dynamic performance.
Khani, Rouhollah; Ghasemi, Jahan B.; Shemirani, Farzaneh
2014-03-01
A powerful and efficient signal-preprocessing technique that combines local and multiscale properties of the wavelet prism with the global filtering capability of orthogonal signal correction (OSC) is applied for pretreatment of spectroscopic data of parabens as model compounds after their preconcentration by robust ionic liquid-based dispersive liquid-liquid microextraction method (IL-DLLME). In the proposed technique, a mixture of a water-immiscible ionic liquid (as extraction solvent) [Hmim][PF6] and disperser solvent is injected into an aqueous sample solution containing one of the IL's ions, NaPF6, as extraction solvent and common ion source. After preconcentration, the absorbance of the extracted compounds was measured in the wavelength range of 200-700 nm. The wavelet orthogonal signal correction with partial least squares (WOSC-PLS) method was then applied for simultaneous determination of each individual compound. Effective parameters, such as amount of IL, volume of the disperser solvent and amount of NaPF6, were inspected by central composite design to identify the most important parameters and their interactions. The effect of pH on the sensitivity and selectivity was studied according to the net analyte signal (NAS) for each component. Under optimum conditions, enrichment factors of the studied compounds were 75 for methyl paraben (MP) and 71 for propyl paraben (PP). Limits of detection for MP and PP were 4.2 and 4.8 ng mL-1, respectively. The root mean square errors of prediction for MP and PP were 0.1046 and 0.1275 μg mL-1, respectively. The practical applicability of the developed method was examined using hygienic, cosmetic, pharmaceutical and natural water samples.
Design and simulation about a self-Tuning fuzzy-PID controller
Institute of Scientific and Technical Information of China (English)
ZHANG Yi; FU Wen-yong; LI Yan-hua; DENG Hao-wen; LIU Hong-chang
2009-01-01
Fuzzy logic has attracted the attention of structural control engineers during the last few years, because fuzzy logic can handle nonlinearities, uncertainties, and heuristic knowledge effectively and easily. In this paper, a self-Tuning fuzzy-PID control method which used the technology of the fuzzy control and PID control unified is presented. These techniques can visualize the results and processes for structure stress. These techniques will also provide convenience for engineers and users, and have high practical values. The MATLAB simulation result shows that the system precision and the efficiency are very high and the static error is small, and robustness was also validated.
Application of single neuron adaptive PID controller during the process of timber drying
Institute of Scientific and Technical Information of China (English)
ZHANG Dong-yan; LIU Ya-qiu; CAO Jun
2003-01-01
The paper presents a method of using single neuron adaptive PID control for adjusting system or servo system to implement timber drying process control, which combines the thought of parameter adaptive PID control and the character of neural network on exactly describing nonlinear and uncertainty dynamic process organically. The method implements functions of adaptive and self-learning by adjusting weighting parameters. Adaptive neural network can make some output trail given hoping value to decouple in static state. The simulation result indicates the validity, veracity and robustness of the method used in the timber drying process
Directory of Open Access Journals (Sweden)
Meysam Gheisarnezhad
2015-01-01
Full Text Available Fractional-order PID (FOPID controller is a generalization of standard PID controller using fractional calculus. Compared with the Standard PID controller, two adjustable variables “differential order” and “integral order” are added to the PID controller.Three tank system is a nonlinear multivariable process that is a good prototype of chemical industrial processes. Cuckoo Optimization Algorithm (COA, that was recently introduced has shown its good performance in optimization problems. In this study, Improved Cuckoo Optimization Algorithm (ICOA has been presented. The aim of the paper is to compare different controllers tuned with a Improved Cuckoo Optimization Algorithm (ICOA for Three Tank System. In order to compare the performance of the optimized FOPID controller with other controllers, Genetic Algorithm(GA, Particle swarm optimization (PSO, Cuckoo Optimization Algorithm (COA and Imperialist Competitive Algorithm (ICA.
PID Techniques: Alternatives to RICH Methods
Va'vra, Jerry
2016-01-01
In this review article we discuss new updates on PID techniques, other than the Cherenkov method. In particular, we discuss recent efforts to develop high resolution timing, placing an emphasis on small scale test results.
Directory of Open Access Journals (Sweden)
Seyed Abbas Taher
2014-03-01
Full Text Available In this paper, fractional order PID (FOPID controller was proposed for load frequency control (LFC in an interconnected power system. This controller had five parameters to be tuned; thus, it provided two more degrees of freedom in comparison with the conventional PID. For proper tuning of the controller parameters, imperialist competitive algorithm (ICA was used. ICA is a new evolutionary algorithm with proved efficiency. In this study, simulation investigations were carried out on a three-area power system with different generating units. These results showed that FOPID controller was robust to the parameter changes in the power system. Also, the simulation results certified much better performance of FOPID controller for LFC in comparison with conventional PID controllers.
Nonlinear Adaptive PID Control for Greenhouse Environment Based on RBF Network
Directory of Open Access Journals (Sweden)
Guanghui Li
2012-04-01
Full Text Available This paper presents a hybrid control strategy, combining Radial Basis Function (RBF network with conventional proportional, integral, and derivative (PID controllers, for the greenhouse climate control. A model of nonlinear conservation laws of enthalpy and matter between numerous system variables affecting the greenhouse climate is formulated. RBF network is used to tune and identify all PID gain parameters online and adaptively. The presented Neuro-PID control scheme is validated through simulations of set-point tracking and disturbance rejection. We compare the proposed adaptive online tuning method with the offline tuning scheme that employs Genetic Algorithm (GA to search the optimal gain parameters. The results show that the proposed strategy has good adaptability, strong robustness and real-time performance while achieving satisfactory control performance for the complex and nonlinear greenhouse climate control system, and it may provide a valuable reference to formulate environmental control strategies for actual application in greenhouse production.
A new PID controller design for automatic generation control of hydro power systems
Energy Technology Data Exchange (ETDEWEB)
Khodabakhshian, A.; Hooshmand, R. [Electrical Engineering Department, University of Isfahan (Iran)
2010-06-15
This paper presents a new robust PID controller for automatic generation control (AGC) of hydro turbine power systems. The method is mainly based on a maximum peak resonance specification that is graphically supported by the Nichols chart. The open-loop frequency response curve is tangent to a specified ellipse and this makes the method to be efficient for controlling the overshoot, the stability and the dynamics of the system. Comparative results of this new load frequency controller with a conventional PI one and also with another PID controller design tested on a multimachine power system show the improvement in system damping remarkably. The region of acceptable performance of the new PID controller covers a wide range of operating and system conditions. (author)
Nonlinear adaptive PID control for greenhouse environment based on RBF network.
Zeng, Songwei; Hu, Haigen; Xu, Lihong; Li, Guanghui
2012-01-01
This paper presents a hybrid control strategy, combining Radial Basis Function (RBF) network with conventional proportional, integral, and derivative (PID) controllers, for the greenhouse climate control. A model of nonlinear conservation laws of enthalpy and matter between numerous system variables affecting the greenhouse climate is formulated. RBF network is used to tune and identify all PID gain parameters online and adaptively. The presented Neuro-PID control scheme is validated through simulations of set-point tracking and disturbance rejection. We compare the proposed adaptive online tuning method with the offline tuning scheme that employs Genetic Algorithm (GA) to search the optimal gain parameters. The results show that the proposed strategy has good adaptability, strong robustness and real-time performance while achieving satisfactory control performance for the complex and nonlinear greenhouse climate control system, and it may provide a valuable reference to formulate environmental control strategies for actual application in greenhouse production.
Comparison of PID Controller Tuning Methods with Genetic Algorithm for FOPTD System
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K. Mohamed Hussain
2014-02-01
Full Text Available Measurement of Level, Temperature, Pressure and Flow parameters are very vital in all process industries. A combination of a few transducers with a controller, that forms a closed loop system leads to a stable and effective process. This article deals with control of in the process tank and comparative analysis of various PID control techniques and Genetic Algorithm (GA technique. The model for such a Real-time process is identified as First Order Plus Dead Time (FOPTD process and validated. The need for improved performance of the process has led to the development of model based controllers. Well-designed conventional Proportional, Integral and Derivative (PID controllers are the most widely used controller in the chemical process industries because of their simplicity, robustness and successful practical applications. Many tuning methods have been proposed for PID controllers. Many tuning methods have been proposed for obtaining better PID controller parameter settings. The comparison of various tuning methods for First Order Plus Dead Time (FOPTD process are analysed using simulation software. Our purpose in this study is comparison of these tuning methods for single input single output (SISO systems using computer simulation.Also efficiency of various PID controller are investigated for different performance metrics such as Integral Square Error (ISE, Integral Absolute Error (IAE, Integral Time absolute Error (ITAE, and Mean square Error (MSE is presented and simulation is carried out. Work in this paper explores basic concepts, mathematics, and design aspect of PID controller. Comparison between the PID controller and Genetic Algorithm (GA will have been carried out to determine the best controller for the temperature system.
Flotation control -- A multivariable stabilizer
Energy Technology Data Exchange (ETDEWEB)
Schubert, J.H.; Henning, R.G.D.; Hulbert, D.G.; Craig, I.K. [Mintek, Randburg (South Africa)
1995-12-31
This paper presents a stabilizing controller for flotation plants which uses a quasi-multivariable technique. The controller monitors all the levels in the plant, and by anticipating interactions between various parts of the plant, is able to stabilize the plant far more successfully than the normal plant control. Once stabilizing control has been achieved, optimization of the process becomes easier and more sustainable. An estimate of the improvement in metallurgical performance is made and a singular value analysis was conducted to verify that the multivariable algorithm will theoretically control better than a collection of individual PID loops. Metallurgical results are presented to show that the improvements are attainable in practice. Control by the Mintek algorithm was alternated with normal plant control, to show that the improvements are statistically significant.
Using PIDs to Support the Full Research Data Publishing Lifecycle
Waard, A. D.
2016-12-01
Persistent identifiers can help support scientific research, track scientific impact and let researchers achieve recognition for their work. We discuss a number of ways in which Elsevier utilizes PIDs to support the scholarly lifecycle: To improve the process of storing and sharing data, Mendeley Data (http://data.mendeley.com) makes use of persistent identifiers to support the dynamic nature of data and software, by tracking and recording the provenance and versioning of datasets. This system now allows the comparison of different versions of a dataset, to see precisely what was changed during a versioning update. To present research data in context for the reader, we include PIDs in research articles as hyperlinks: https://www.elsevier.com/books-and-journals/content-innovation/data-base-linking. In some cases, PIDs fetch data files from the repositories provide that allow the embedding of visualizations, e.g. with PANGAEA and PubChem: https://www.elsevier.com/books-and-journals/content-innovation/protein-viewer; https://www.elsevier.com/books-and-journals/content-innovation/pubchem. To normalize referenced data elements, the Resource Identification Initiative - which we developed together with members of the Force11 RRID group - introduces a unified standard for resource identifiers (RRIDs) that can easily be interpreted by both humans and text mining tools. https://www.force11.org/group/resource-identification-initiative/update-resource-identification-initiative, as can be seen in our Antibody Data app: https://www.elsevier.com/books-and-journals/content-innovation/antibody-data To enable better citation practices and support robust metrics system for sharing research data, we have helped develop, and are early adopters of the Force11 Data Citation Principles and Implementation groups (https://www.force11.org/group/dcip) Lastly, through our work with the Research Data Alliance Publishing Data Services group, we helped create a set of guidelines (http
Goher, K M; Fadlallah, S O
2017-01-01
This paper presents the performance of utilizing a bacterial foraging optimization algorithm on a PID control scheme for controlling a five DOF two-wheeled robotic machine with two-directional handling mechanism. The system under investigation provides solutions for industrial robotic applications that require a limited-space working environment. The system nonlinear mathematical model, derived using Lagrangian modeling approach, is simulated in MATLAB/Simulink(®) environment. Bacterial foraging-optimized PID control with decoupled nature is designed and implemented. Various working scenarios with multiple initial conditions are used to test the robustness and the system performance. Simulation results revealed the effectiveness of the bacterial foraging-optimized PID control method in improving the system performance compared to the PID control scheme.
Design High Efficiency-Minimum Rule Base PID Like Fuzzy Computed Torque Controller
Directory of Open Access Journals (Sweden)
Alireza Khalilian
2014-06-01
Full Text Available The minimum rule base Proportional Integral Derivative (PID Fuzzy Computed Torque Controller is presented in this research. The popularity of PID Fuzzy Computed Torque Controller can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID Fuzzy Computed Torque Controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing. PID methodology has three inputs and if any input is described with seven linguistic values, and any rule has three conditions we will need 343 rules. It is too much work to write 343 rules. In this research the PID-like fuzzy controller can be constructed as a parallel structure of a PD-like fuzzy controller and a PI controller to have the minimum rule base. However computed torque controller is work based on cancelling decoupling and nonlinear terms of dynamic parameters of each link, this controller is work based on manipulator dynamic model and this technique is highly sensitive to the knowledge of all parameters of nonlinear robot manipulator’s dynamic equation. This research is used to reduce or eliminate the computed torque controller problem based on minimum rule base fuzzy logic theory to control of flexible robot manipulator system and testing of the quality of process control in the simulation environment of MATLAB/SIMULINK Simulator.
Design High-Efficiency Intelligent PID like Fuzzy Backstepping Controller for Three Dimension Motor
Directory of Open Access Journals (Sweden)
Mahsa Piltan
2014-08-01
Full Text Available The minimum rule base Proportional Integral Derivative (PID Fuzzy backstepping Controller for three dimensions spherical motor is presented in this research. The popularity of PID Fuzzy backstepping controller can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID Fuzzy backstepping controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing. PID methodology has three inputs and if any input is described with seven linguistic values, and any rule has three conditions we will need 7 × 7 × 7 = 343 rules. It is too much work to write 343 rules. In this research the PID-like fuzzy controller can be constructed as a parallel structure of a PI-like controller and a PD-like fuzzy controller to have the minimum rule base. However backstepping controller is work based on cancelling decoupling and nonlinear terms of dynamic parameters of each dimension, this controller is work based on spherical motor dynamic model and this technique is highly sensitive to the knowledge of all parameters of nonlinear three dimension spherical motor’s dynamic equation. This research is used to reduce or eliminate the backstepping controller problem based on minimum rule base fuzzy logic theory to control of spherical motor system and testing of the quality of process control in the simulation environment of MATLAB/SIMULINK Simulator.
A fuzzy model based adaptive PID controller design for nonlinear and uncertain processes.
Savran, Aydogan; Kahraman, Gokalp
2014-03-01
We develop a novel adaptive tuning method for classical proportional-integral-derivative (PID) controller to control nonlinear processes to adjust PID gains, a problem which is very difficult to overcome in the classical PID controllers. By incorporating classical PID control, which is well-known in industry, to the control of nonlinear processes, we introduce a method which can readily be used by the industry. In this method, controller design does not require a first principal model of the process which is usually very difficult to obtain. Instead, it depends on a fuzzy process model which is constructed from the measured input-output data of the process. A soft limiter is used to impose industrial limits on the control input. The performance of the system is successfully tested on the bioreactor, a highly nonlinear process involving instabilities. Several tests showed the method's success in tracking, robustness to noise, and adaptation properties. We as well compared our system's performance to those of a plant with altered parameters with measurement noise, and obtained less ringing and better tracking. To conclude, we present a novel adaptive control method that is built upon the well-known PID architecture that successfully controls highly nonlinear industrial processes, even under conditions such as strong parameter variations, noise, and instabilities.
A mathematical explanation via "intelligent" PID controllers of the strange ubiquity of PIDs
Novel, Brigitte D'Andrea; Join, Cédric; Mounier, Hugues; Steux, Bruno
2010-01-01
The ubiquity of PID controllers in the industry has remained mysterious until now. We provide here a mathematical explanation of this strange phenomenon by comparing their sampling with the the one of "intelligent" PID controllers, which were recently introduced. Some computer simulations nevertheless confirm the superiority of the new intelligent feedback design.
Robust Adaptive Control of Multivariable Nonlinear Systems
2011-03-28
IEEE Transactions on Automatic Control , 42(9): 1200-1221, 1997. 6. D. Li, N. Hovakimyan...limitations of performance,” IEEE Transactions on Automatic Control , vol. 52, no. 7, pp. 1604–1615, 2008. 8. X. Wang, N. Hovakimyan, 1L Adaptive...550-564, 2010. 5. C. Cao, N. Hovakimyan, Stability Margins of 1L Adaptive Control Architecture, IEEE Transactions on Automatic Control , vol. 55,
Relationship between fuzzy controllers and PID controllers
Institute of Scientific and Technical Information of China (English)
李洪兴
1999-01-01
The internal relations between fuzzy controllers and PID controllers are revealed. First, it is pointed out that a fuzzy controller with one input and one output is just a piecewise P controller. Then it is proved that a fuzzy controller with two inputs and one output is just a piecewise PD (or I) controller with interaction between P and D (or PI). At last, the conclusion that a fuzzy controller with three inputs and one output is just a piecewise PID controller with interaction among P, I and D is given. Moreover, a kind of difference scheme of fuzzy controllers is designed.
Tuning of PID controllers for integrating systems using direct synthesis method.
Anil, Ch; Padma Sree, R
2015-07-01
A PID controller is designed for various forms of integrating systems with time delay using direct synthesis method. The method is based on comparing the characteristic equation of the integrating system and PID controller with a filter with the desired characteristic equation. The desired characteristic equation comprises of multiple poles which are placed at the same desired location. The tuning parameter is adjusted so as to achieve the desired robustness. Tuning rules in terms of process parameters are given for various forms of integrating systems. The tuning parameter can be selected for the desired robustness by specifying Ms value. The proposed controller design method is applied to various transfer function models and to the nonlinear model equations of jacketed CSTR to show its effectiveness and applicability.
Implementation of Fuzzy-PID in Smart Car Control
Institute of Scientific and Technical Information of China (English)
2010-01-01
<正>An unmanued smart car control system and the fuzzy-PID control algorithm are produced.A design scheme of fuzzy-PID controller is put forward.The simulation analysis from matlab indicated that the dynamic performance of fuzzy-PID control algorithm is better than that of usual PID.Experimental result of smart car show that it can follow the black guid line well and fast-stable complete running the whole trip.
Design New PID like Fuzzy CTC Controller: Applied to Spherical Motor
Directory of Open Access Journals (Sweden)
Mohammad shamsodini
2014-05-01
Full Text Available The minimum rule base Proportional Integral Derivative (PID Fuzzy Computed Torque Controller with application to spherical motor is presented in this research. The popularity of PID Fuzzy Computed Torque Controller can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. PID methodology has three inputs and if any input is described with seven linguistic values, and any rule has three conditions we will need 343 rules. It is too much work to write 343 rules and have lots of problem to design embedded control system e.g., Field Programmable Gate Array (FPGA. In this research the PID-like fuzzy controller can be constructed as a parallel structure of a PD-like fuzzy controller and a conventional PI controller to have the minimum rule base and acceptable trajectory follow disturbance to control of spherical motor. However computed torque controller is work based on cancelling decoupling and nonlinear terms of dynamic parameters for each direction of three degree of freedom spherical motor, this controller is work based on motor dynamic model and this technique is highly sensitive to the knowledge of all parameters of nonlinear spherical motor’s dynamic equation. This research is used to reduce or eliminate the computed torque controller problem based on minimum rule base fuzzy logic theory to control of three degrees of freedom spherical motor system and testing of the quality of process control in the simulation environment of MATLAB/SIMULINK Simulator.
Eukaryotic expression, purification, identification, and tissuedistribution of porcine PID1
Chen, Xiaoling; Wang, Huan; ZHOU, BO; Huang, Zhiqing; Jia, Gang; Liu, Guangmang; Zhao, Hua
2015-01-01
Abstract: Phosphotyrosine interaction domain containing 1 (PID1) is a recently discovered gene related to lipid metabolism and may play an important role in fat deposition. In this study, in order to scale up the production of the active recombinant porcine PID1 (pPID1) protein, we reported the expression and purification of a His-tagged version of pPID1 in the yeast Pichia pastoris. The pPID1 cDNA was cloned into the pPICZαA vector and was expressed in methylotrophic yeast (P. ...
Genetic Optimization Algorithm of PID Decoupling Control for VAV Air-Conditioning System
Institute of Scientific and Technical Information of China (English)
WANG Jiangjiang; AN Dawei; ZHANG Chunfa; JING Youyin
2009-01-01
Variable-air-volume (VAV) air-conditioning system is a multi-variable system and has multi coupling control loops. While all of the control loops are working together, they interfere and influence each other. A multi-variable decoupling PID controller is designed for VAV air-conditioning system. Diagonal matrix decoupling method is employed to eliminate the coupling between the loop of supply air temperature and that of thermal-space air temperature. The PID controller parameters are optimized by means of an improved genetic algorithm in floating point representations to obtain better performance. The population in the improved genetic algorithm mutates before crossover, which is helpful for the convergence. Additionally the micro mutation algorithm is proposed and applied to improve the convergence during the later evolution. To search the best parameters, the optimized parameters ranges should be amplified l0 times the initial ideal parameters. The simulation and experiment results show that the decoupling control system is effective and feasible. The method can overcome the strong coupling feature of the system and has shorter governing time and less over-shoot than non-optimization PID control.
Study finds OC users protected against onset of chlamydial PID.
1987-09-01
Preliminary results from a large case-controlled study on the relationship between oral contraceptives and chlamydial infections refute the suspicion that pills increase the chance of contracting chlamydia, and clearly show that pills inhibit progression of an existing infection into chlamydial pelvic inflammatory disease (PID). The research was conducted in Seattle at Washington University. Subjects recruited from a sexually transmitted disease clinic included 700 patients, 100 with clinically verified PID, classified into those with chlamydia, gonorrhea, neither, and PID or no PID. Compared to 762 controls, oral contraceptive users had 1/8 the risk of chlamydial PID; compared to women using no contraception, their risk was 1/11. Oral contraception was safer than other methods with respect to chlamydial PID. No such pattern was evident when gonorrhea incidence was examined. It should be emphasized that pills do not protect against other types of PID. Nor do they prevent the start of a chlamydia infection.
Das, Saptarshi; Maharatna, Koushik
2016-01-01
In this paper, an efficient control strategy for physiological interaction based anaesthetic drug infusion model is explored using the fractional order (FO) proportional integral derivative (PID) controllers. The dynamic model is composed of several human organs by considering the brain response to the anaesthetic drug as output and the drug infusion rate as the control input. Particle Swarm Optimisation (PSO) is employed to obtain the optimal set of parameters for PID/FOPID controller structures. With the proposed FOPID control scheme much less amount of drug-infusion system can be designed to attain a specific anaesthetic target and also shows high robustness for +/-50% parametric uncertainty in the patient's brain model.
Li, Mingjie; Zhou, Ping; Zhao, Zhicheng; Zhang, Jinggang
2016-03-01
Recently, fractional order (FO) processes with dead-time have attracted more and more attention of many researchers in control field, but FO-PID controllers design techniques available for the FO processes with dead-time suffer from lack of direct systematic approaches. In this paper, a simple design and parameters tuning approach of two-degree-of-freedom (2-DOF) FO-PID controller based on internal model control (IMC) is proposed for FO processes with dead-time, conventional one-degree-of-freedom control exhibited the shortcoming of coupling of robustness and dynamic response performance. 2-DOF control can overcome the above weakness which means it realizes decoupling of robustness and dynamic performance from each other. The adjustable parameter η2 of FO-PID controller is directly related to the robustness of closed-loop system, and the analytical expression is given between the maximum sensitivity specification Ms and parameters η2. In addition, according to the dynamic performance requirement of the practical system, the parameters η1 can also be selected easily. By approximating the dead-time term of the process model with the first-order Padé or Taylor series, the expressions for 2-DOF FO-PID controller parameters are derived for three classes of FO processes with dead-time. Moreover, compared with other methods, the proposed method is simple and easy to implement. Finally, the simulation results are given to illustrate the effectiveness of this method.
Implementasi Kontrol PID pada Mesin Pengembang Roti
Directory of Open Access Journals (Sweden)
Novianti Yuliarmas
2015-04-01
Full Text Available Besides the ingredient composition, another important thing in the process of making dough is proofing, ie. dough rising process prior to roasting process. Proofing process requires a stable temperature to ensure that the dough is well rising. The purpose of this research is to make a proofing machine that uses DHT11 as a temperature sensor. Proportional-Integral-Derivative (PID controller is implemented to guarantee that the machine remains at the temperature of 350Celcius, in which the fermentation process would success. PID control has been implemented in fluorescent lamp which been set its dim light to generate heat until it reach a predetermined set point value. The temperature was monitored using LCD and set to remain stable with the help of fan. The proofing process will last for 15 minutes which ended by the sound of the buzzer. The testing result shows that the value of , , will reach set point value within 120 seconds.
Variable-order fuzzy fractional PID controller.
Liu, Lu; Pan, Feng; Xue, Dingyu
2015-03-01
In this paper, a new tuning method of variable-order fractional fuzzy PID controller (VOFFLC) is proposed for a class of fractional-order and integer-order control plants. Fuzzy logic control (FLC) could easily deal with parameter variations of control system, but the fractional-order parameters are unable to change through this way and it has confined the effectiveness of FLC. Therefore, an attempt is made in this paper to allow all the five parameters of fractional-order PID controller vary along with the transformation of system structure as the outputs of FLC, and the influence of fractional orders λ and μ on control systems has been investigated to make the fuzzy rules for VOFFLC. Four simulation results of different plants are shown to verify the availability of the proposed control strategy.
Energy Technology Data Exchange (ETDEWEB)
Vasconcelos, Wagner Eustaquio de; Lira, Carlos Alberto Brayner de Oliveira; Brito, Thiago Souza Pereira de; Afonso, Antonio Claudio Marques, E-mail: wagner@unicap.br, E-mail: cabol@ufpe.br, E-mail: afonsofisica@gmail.com, E-mail: thiago.brito86@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Tecnologia e Geociencias. Departamento de Energia Nuclear; Cruz Filho, Antonio Jose da; Marques, Jose Antonio, E-mail: antonio.jscf@gmail.com, E-mail: jamarkss@uol.com.br [Universidade Catolica de Pernambuco (CCT/PUC-PE), Recife, PE (Brazil). Centro de Ciencias e Tecnologia; Teixeira, Marcello Goulart, E-mail: marcellogt@dcc.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Matematica. Dept. de Matematica
2013-07-01
Nuclear reactors are in nature nonlinear systems and their parameters vary with time as a function of power level. These characteristics must be considered if large power variations occur in power plant operational regimes, such as in load-following conditions. A PWR reactor has a component called pressurizer, whose function is to supply the necessary high pressure for its operation and to contain pressure variations in the primary cooling system. The use of control systems capable of reducing fast variations of the operation variables and to maintain the stability of this system is of fundamental importance. The best-known controllers used in industrial control processes are proportional-integral-derivative (PID) controllers due to their simple structure and robust performance in a wide range of operating conditions. However, designing a fuzzy controller is seen to be a much less difficult task. Once a Fuzzy Logic controller is designed for a particular set of parameters of the nonlinear element, it yields satisfactory performance for a range of these parameters. The objective of this work is to develop fuzzy proportional-integral-derivative (fuzzy-PID) control strategies to control the level of water in the reactor. In the study of the pressurizer, several computer codes are used to simulate its dynamic behavior. At the fuzzy-PID control strategy, the fuzzy logic controller is exploited to extend the finite sets of PID gains to the possible combinations of PID gains in stable region. Thus the fuzzy logic controller tunes the gain of PID controller to adapt the model with changes in the water level of reactor. The simulation results showed a favorable performance with the use to fuzzy-PID controllers. (author)
Analytical Design of Robust Multi-loop PI Controller for Multi-time Delay Processes
Vu, Truong Nguyen Luan; Lee, Moonyong
In this chapter, a robust design of multi-loop PI controller for multivariable processes in the presence of the multiplicative input uncertainty is presented. The method consists of two major steps: firstly, the analytical tuning rules of multi-loop PI controller are derived based on the direct synthesis and IMC-PID approach. Then, in the second step, the robust stability analysis is utilized for enhancing the robustness of proposed PI control systems. The most important feature of the proposed method is that the tradeoff between the robust stability and performance can be established by adjusting only one design parameter (i.e., the closed-loop time constant) via structured singular value synthesis. To verify the superiority of the proposed method, simulation studies have been conducted on a variety of the nominal processes and their plant-model mismatch cases. The results demonstrate that the proposed design method guarantees the robustness under the perturbation on each of the process parameters simultaneously.
Computing strategy for PID calibration samples for LHCb Run 2
Anderlini, Lucio; Lupton, Olli; Sciascia, Barbara; Gligorov, Vladimir
2016-01-01
The samples for the calibration of the Particle Identification (PID) are sets of data collected by LHCb where decay candidates have a kinematic structure which allows unambiguous identification of one the daughters with a selection strategy not relying on its PID-related variables. PID calibration samples are used in a data-driven technique to measure the efficiency of selection requirements on PID variables in many LHCb analyses. Since the second run of the LHCb experiment, PID variable are computed as part of the software trigger and then refined in the offline reconstruction (this includes two different applications, named Brunel and DaVinci). Physics analyses rely on selections combining PID requirements on the online and offline versions of the PID variables. Because of the large, but not full, correlation between online and offline PID variables, the PID samples must be built such that it is possible to access, particle by particle, both versions of the full PID information, such that combined requireme...
An optimal PID controller via LQR for standard second order plus time delay systems.
Srivastava, Saurabh; Misra, Anuraag; Thakur, S K; Pandit, V S
2016-01-01
An improved tuning methodology of PID controller for standard second order plus time delay systems (SOPTD) is developed using the approach of Linear Quadratic Regulator (LQR) and pole placement technique to obtain the desired performance measures. The pole placement method together with LQR is ingeniously used for SOPTD systems where the time delay part is handled in the controller output equation instead of characteristic equation. The effectiveness of the proposed methodology has been demonstrated via simulation of stable open loop oscillatory, over damped, critical damped and unstable open loop systems. Results show improved closed loop time response over the existing LQR based PI/PID tuning methods with less control effort. The effect of non-dominant pole on the stability and robustness of the controller has also been discussed.
GA-BASED PID NEURAL NETVVORK CONTROL FOR MAGNETIC BEARING SYSTEMS
Institute of Scientific and Technical Information of China (English)
LI Guodong; ZHANG Qingchun; LIANG Yingchun
2007-01-01
In order to overcome the system non-linearity and uncertainty inherent in magnetic bearing systems, a GA(genetic algorithm)-based PID neural network controller is designed and trained to emulate the operation of a complete system (magnetic beating, controller, and power amplifiers).The feasibility of using a neural network to control nonlinear magnetic beating systems with unknown dynamics is demonstrated. The key concept of the control scheme is to use GA to evaluate the candidate solutions (chromosomes), increase the generalization ability of PID neural network and avoid suffering from the local minima problem in network learning due to the use of gradient descent learning method. The simulation results show that the proposed architecture provides well robust performance and better reinforcement learning capability in controlling magnetic bearing systems.
Directory of Open Access Journals (Sweden)
Chengqiang Yin
2014-01-01
Full Text Available A two-degree-of-freedom control structure is proposed for a class of unstable processes with time delay based on modified Smith predictor control; the superior performance of disturbance rejection and good robust stability are gained for the system. The set-point tracking controller is designed using the direct synthesis method; the IMC-PID controller for disturbance rejection is designed based on the internal mode control design principle. The controller for set-point response and the controller for disturbance rejection can be adjusted and optimized independently. Meanwhile, the two controllers are designed in the form of PID, which is convenient for engineering application. Finally, simulation examples demonstrate the validity of the proposed control scheme.
船舶动力定位手柄操作模式PID解耦控制%PID decoupling control for joystick mode of dynamic positioned ships
Institute of Scientific and Technical Information of China (English)
张景鸿; 王钦若; 叶宝玉; 熊建斌
2012-01-01
针对船舶动力定位手柄操作模式表现出的多变量、强耦合、非线性和时变性等特点,提出了一种增量式PID解耦控制方法.考虑横荡速度与艏摇角速度之间的耦合问题,采用前馈补偿解耦法对船舶的动力学模型进行解耦；根据解耦后的船舶动力学模型,采用增量式PID控制算法分别对纵荡速度、横荡速度和艏摇角3个自由度设计相应的控制器.仿真结果表明,该控制器跟踪快、实时性较好、鲁棒性强,可以满足工程应用的要求.%Aimed at the characteristics of multi-variable, strong coupling, nonliear and time-varying in joystick mode of ship motion control, a control algorithm of incremental PID decoupling is presented. Firstly, to address the coupling problem between sway velocity and yaw rate, the ship kinetic model is decoupled by feedforward compensation decoupling method. Then, incremental PID control algorithm is used according to the decoupling ship kinetic model to design corresponding controller of surge velocity, sway velocity and yaw angle, the simulation results show that the controller can track fast, has good real-time and strong robustness. It also meets the requirements of engineering applications.
Fuzzy-PID controlled lift feedback fin stabilizer
Institute of Scientific and Technical Information of China (English)
LIANG Yan-hua; JIN Hong-zhang; LIANG Li-hua
2008-01-01
Conventional PID controllers are widely used in fin stabilizer control systems,but they have time-variations,nonlinearity,and uncertainty influencing their control effects.A lift feedback fuzzy-PID control method was developed to better deal with these problems,and this lift feedback fin stabilizer system was simulated under different sea condition.Test results showed the system has better anti-rolling performance than traditional fin-angle PID control systems.
Fuzzy-Immune PID Control for AMB Systems
Institute of Scientific and Technical Information of China (English)
SU Yixin; LI Xuan; ZHOU Zude; CHEN Youping; ZHANG Danhong
2006-01-01
In order to improve the dynamic performance of active magnetic bearing systems with highly nonlinear and naturally unstable dynamics, a new nonlinear fuzzy-immune proportional-integral-derivative (PID) controller is proposed by combining the immune feedback law with linear PID control. This controller consists of a PID controller and a basic immune proportional controller in cascaded connection, the nonlinear function of the immune proportional controller is realized by using fuzzy reasoning. Simulation results demonstrate that the active magnetic bearing system with the proposed controller has better dynamic performance and disturbance rejection ability than using the linear PID controller.
Soft Real-Time PID Control on a VME Computer
Karayan, Vahag; Sander, Stanley; Cageao, Richard
2007-01-01
microPID (uPID) is a computer program for real-time proportional + integral + derivative (PID) control of a translation stage in a Fourier-transform ultraviolet spectrometer. microPID implements a PID control loop over a position profile at sampling rate of 8 kHz (sampling period 125microseconds). The software runs in a strippeddown Linux operating system on a VersaModule Eurocard (VME) computer operating in real-time priority queue using an embedded controller, a 16-bit digital-to-analog converter (D/A) board, and a laser-positioning board (LPB). microPID consists of three main parts: (1) VME device-driver routines, (2) software that administers a custom protocol for serial communication with a control computer, and (3) a loop section that obtains the current position from an LPB-driver routine, calculates the ideal position from the profile, and calculates a new voltage command by use of an embedded PID routine all within each sampling period. The voltage command is sent to the D/A board to control the stage. microPID uses special kernel headers to obtain microsecond timing resolution. Inasmuch as microPID implements a single-threaded process and all other processes are disabled, the Linux operating system acts as a soft real-time system.
Optimasi Pengendali PID pada Pesawat Autopilot Berbasiskan Algoritma Genetika
Directory of Open Access Journals (Sweden)
Muhammad Ilhamdi Rusydi
2016-07-01
Full Text Available Nowadays, technology counts automation as one of the considerable features on it. The ability of machine to work independently become very important, like in aircraft industry. Aircrafts which able to decide their own path are called autopilot. In this research, the control system of pesawat was designed to keep it fly on the reference of high based on the pilot demands. Using the transfer function of aircraft, PID controller was designed based on genetic algorithm (PID-GA. The performance of PID-GA was compared to the PID which was tuned by Ziegler-Nichlos. The result showed that the chosen PID-GA which the threshold, generation and population are 10, 30, 50 performed better performance than PID-ZN. The parameter of proportional, integral and derivate controller are 9,66, 9,15 and 9.06. The specification of the system performance based on PID-GA were 0.55 second of rise time, 5.3 second of rise time. This result were better than the PID-ZN results. The system performance based on PID-ZN 0.732 second of rise time and 19.1 second of settling time.
The Parrot UAV Controlled by PID Controllers
Directory of Open Access Journals (Sweden)
Koszewnik Andrzej
2014-08-01
Full Text Available The paper presents the process of modeling and designing control laws for four-rotor type of the Parrot UAV. The state space model is obtained by using several phenomena like gyroscopic effects for rigid bodies, propellers and rotors. The obtained model has been used to design PID control laws for roll, pitch, yaw angle and altitude, respectively. The numerical simulations of the closed loop model are shown that system in satisfy way stabilize flight of the quadro-rotor in all considered directions.
Energy Technology Data Exchange (ETDEWEB)
Jacob, D. [Institut Universitaire de Technologie, 86 - Poitiers (France)
2004-09-15
The proportional integral derived function (PID) control is certainly not the most efficient but it is the most widely control used in regulation systems. The implementation of a PID regulator does not offer all adjustment possibilities of modern methods and it is in general impossible to make open-loop tests to identify the regulated system. This paper presents two concrete applications of PID control systems: one for a temperature regulation and the other for the servo-control of a mechanical system driven by a brush-less motor. The adjustment is performed using the classical momentum and frequency methods: 1 - PID control; 2 - efficiencies obtained in close loop configuration; 3 - principle of the experimental adjustment method of PID systems; 4 - experimental identification in close-loop configuration; 5 - calculation principle of a PID corrector; 6 - PID control for a class 0 system; 7 - calculation of a PID corrector for a class 1 system; 8 - PID position regulation of a brush-less motor; 9 - remarks about the numerical calculation of the control; 10 - summary of the models presented. (J.S.)
A PID autotuner utilizing GPC and constraint optimization
DEFF Research Database (Denmark)
Henningsen, Arne; Christensen, Anders; Ravn, Ole
1990-01-01
a generalized predictive control criterion, and the PID structure is ensured by constraining the parameters to a feasible set defined by the discrete-time Euler approximation of the ideal continuous-time PID controller. The algorithm is extended by incorporating constraints on the amplitude and slew...
Analytical one parameter method for PID motion controller settings
Dijk, van J.; Aarts, R.G.K.M.
2012-01-01
In this paper analytical expressions for PID-controllers settings for electromechanical motion systems are presented. It will be shown that by an adequate frequency domain oriented parametrization, the parameters of a PID-controller are analytically dependent on one variable only, the cross-over fre
Kumar, Anupam; Kumar, Vijay
2017-05-01
In this paper, a novel concept of an interval type-2 fractional order fuzzy PID (IT2FO-FPID) controller, which requires fractional order integrator and fractional order differentiator, is proposed. The incorporation of Takagi-Sugeno-Kang (TSK) type interval type-2 fuzzy logic controller (IT2FLC) with fractional controller of PID-type is investigated for time response measure due to both unit step response and unit load disturbance. The resulting IT2FO-FPID controller is examined on different delayed linear and nonlinear benchmark plants followed by robustness analysis. In order to design this controller, fractional order integrator-differentiator operators are considered as design variables including input-output scaling factors. A new hybridized algorithm named as artificial bee colony-genetic algorithm (ABC-GA) is used to optimize the parameters of the controller while minimizing weighted sum of integral of time absolute error (ITAE) and integral of square of control output (ISCO). To assess the comparative performance of the IT2FO-FPID, authors compared it against existing controllers, i.e., interval type-2 fuzzy PID (IT2-FPID), type-1 fractional order fuzzy PID (T1FO-FPID), type-1 fuzzy PID (T1-FPID), and conventional PID controllers. Furthermore, to show the effectiveness of the proposed controller, the perturbed processes along with the larger dead time are tested. Moreover, the proposed controllers are also implemented on multi input multi output (MIMO), coupled, and highly complex nonlinear two-link robot manipulator system in presence of un-modeled dynamics. Finally, the simulation results explicitly indicate that the performance of the proposed IT2FO-FPID controller is superior to its conventional counterparts in most of the cases. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
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Santos Coelho, Leandro dos [Pontifical Catholic University of Parana, PUCPR Industrial and Systems Engineering Graduate Program, LAS/PPGEPS Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil)], E-mail: leandro.coelho@pucpr.br
2009-02-28
Despite the popularity, the tuning aspect of proportional-integral-derivative (PID) controllers is a challenge for researchers and plant operators. Various controllers tuning methodologies have been proposed in the literature such as auto-tuning, self-tuning, pattern recognition, artificial intelligence, and optimization methods. Chaotic optimization algorithms as an emergent method of global optimization have attracted much attention in engineering applications. Chaotic optimization algorithms, which have the features of easy implementation, short execution time and robust mechanisms of escaping from local optimum, is a promising tool for engineering applications. In this paper, a tuning method for determining the parameters of PID control for an automatic regulator voltage (AVR) system using a chaotic optimization approach based on Lozi map is proposed. Since chaotic mapping enjoys certainty, ergodicity and the stochastic property, the proposed chaotic optimization introduces chaos mapping using Lozi map chaotic sequences which increases its convergence rate and resulting precision. Simulation results are promising and show the effectiveness of the proposed approach. Numerical simulations based on proposed PID control of an AVR system for nominal system parameters and step reference voltage input demonstrate the good performance of chaotic optimization.
Decentralized PID neural network control for a quadrotor helicopter subjected to wind disturbance
Institute of Scientific and Technical Information of China (English)
陈彦民; 何勇灵; 周岷峰
2015-01-01
A decentralized PID neural network (PIDNN) control scheme was proposed to a quadrotor helicopter subjected to wind disturbance. First, the dynamic model that considered the effect of wind disturbance was established via Newton−Euler formalism. For quadrotor helicopter flying at low altitude in actual situation, it was more susceptible to be influenced by the turbulent wind field. Therefore, the turbulent wind field was generated according to Dryden model and taken into consideration as the disturbance source of quadrotor helicopter. Then, a nested loop control approach was proposed for the stabilization and navigation problems of the quadrotor subjected to wind disturbance. A decentralized PIDNN controller was designed for the inner loop to stabilize the attitude angle. A conventional PID controller was used for the outer loop in order to generate the reference path to inner loop. Moreover, the connective weights of the PIDNN were trained on-line by error back-propagation method. Furthermore, the initial connective weights were identified according to the principle of PID control theory and the appropriate learning rate was selected by discrete Lyapunov theory in order to ensure the stability. Finally, the simulation results demonstrate that the controller can effectively resist external wind disturbances, and presents good stability, maneuverability and robustness.
Design Robust Controller for Rotary Kiln
Directory of Open Access Journals (Sweden)
Omar D. Hernández-Arboleda
2013-11-01
Full Text Available This paper presents the design of a robust controller for a rotary kiln. The designed controller is a combination of a fractional PID and linear quadratic regulator (LQR, these are not used to control the kiln until now, in addition robustness criteria are evaluated (gain margin, phase margin, strength gain, rejecting high frequency noise and sensitivity applied to the entire model (controller-plant, obtaining good results with a frequency range of 0.020 to 90 rad/s, which contributes to the robustness of the system.
An improved auto-tuning scheme for PID controllers.
Dey, Chanchal; Mudi, Rajani K
2009-10-01
An improved auto-tuning scheme is proposed for Ziegler-Nichols (ZN) tuned PID controllers (ZNPIDs), which usually provide excessively large overshoots, not tolerable in most of the situations, for high-order and nonlinear processes. To overcome this limitation ZNPIDs are upgraded by some easily interpretable heuristic rules through an online gain modifying factor defined on the instantaneous process states. This study is an extension of our earlier work [Mudi RK., Dey C. Lee TT. An improved auto-tuning scheme for PI controllers. ISA Trans 2008; 47: 45-52] to ZNPIDs, thereby making the scheme suitable for a wide range of processes and more generalized too. The proposed augmented ZNPID (AZNPID) is tested on various high-order linear and nonlinear dead-time processes with improved performance over ZNPID, refined ZNPID (RZNPID), and other schemes reported in the literature. Stability issues are addressed for linear processes. Robust performance of AZNPID is observed while changing its tunable parameters as well as the process dead-time. The proposed scheme is also implemented on a real time servo-based position control system.
Optimized PID control of depth of hypnosis in anesthesia.
Padula, Fabrizio; Ionescu, Clara; Latronico, Nicola; Paltenghi, Massimiliano; Visioli, Antonio; Vivacqua, Giulio
2017-06-01
This paper addresses the use of proportional-integral-derivative controllers for regulating the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable. In fact, introducing an automatic control system might provide significant benefits for the patient in reducing the risk for under- and over-dosing. In this study, the controller parameters are obtained through genetic algorithms by solving a min-max optimization problem. A set of 12 patient models representative of a large population variance is used to test controller robustness. The worst-case performance in the considered population is minimized considering two different scenarios: the induction case and the maintenance case. Our results indicate that including a gain scheduling strategy enables optimal performance for induction and maintenance phases, separately. Using a single tuning to address both tasks may results in a loss of performance up to 102% in the induction phase and up to 31% in the maintenance phase. Further on, it is shown that a suitably designed low-pass filter on the controller output can handle the trade-off between the performance and the noise effect in the control variable. Optimally tuned PID controllers provide a fast induction time with an acceptable overshoot and a satisfactory disturbance rejection performance during maintenance. These features make them a very good tool for comparison when other control algorithms are developed. Copyright © 2017 Elsevier B.V. All rights reserved.
Design Intelligent PID like Fuzzy Sliding Mode Controller for Spherical Motor
Directory of Open Access Journals (Sweden)
Farzin Matin
2014-04-01
Full Text Available The minimum rule base Proportional Integral Derivative (PID Fuzzy Sliding Mode Controller (SMC with application to spherical motor is presented in this research. The popularity of PID Fuzzy Sliding Mode Controller can be attributed to their robust performance in a wide range of operating conditions and partly to their functional simplicity. The process of setting of PID Fuzzy Sliding Mode Controller can be determined as an optimization task. Over the years, use of intelligent strategies for tuning of these controllers has been growing especially in nonlinear and uncertain systems. Proportional Integral Derivative methodology has three inputs and if any input is described with seven linguistic values, and any rule has three conditions, we will need 343 rules. It is too much work to write 343 rules and have lots of problem to design embedded control system e.g., Field Programmable Gate Array (FPGA. In this research the PID-like fuzzy controller can be constructed as a parallel structure of a PD-like fuzzy controller and a conventional PI controller to have the minimum rule base and good trajectory follow disturbance to control of spherical motor. However Sliding Mode Controller is work based on cancelling decoupling and nonlinear terms of dynamic parameters for each direction of three degree of freedom spherical motor, this controller is work based on motor dynamic model and this technique is highly sensitive to the knowledge of all parameters of nonlinear spherical motor’s dynamic equation which caused to challenge in uncertain system. This research is used to reduce or eliminate the Sliding Mode Controller problem based on minimum rule base fuzzy logic theory to control of three degrees of freedom spherical motor system and testing of the quality of process control in the simulation environment of MATLAB/SIMULINK Simulator.
International Conference on Robust Statistics
Filzmoser, Peter; Gather, Ursula; Rousseeuw, Peter
2003-01-01
Aspects of Robust Statistics are important in many areas. Based on the International Conference on Robust Statistics 2001 (ICORS 2001) in Vorau, Austria, this volume discusses future directions of the discipline, bringing together leading scientists, experienced researchers and practitioners, as well as younger researchers. The papers cover a multitude of different aspects of Robust Statistics. For instance, the fundamental problem of data summary (weights of evidence) is considered and its robustness properties are studied. Further theoretical subjects include e.g.: robust methods for skewness, time series, longitudinal data, multivariate methods, and tests. Some papers deal with computational aspects and algorithms. Finally, the aspects of application and programming tools complete the volume.
Directory of Open Access Journals (Sweden)
V Soni
2016-04-01
Full Text Available The combination of Grey Wolf Optimization and Pattern Search Technique (hGWO-PS has been introduced to optimize the parameters of two Degree of Freedom Proportional-Integral-Derivative Controller (2DOF-PID for controlling the load frequency in Automatic Generation Control (AGC for interconnected power system. The interconnected two area power system of non-reheat thermal power plants consisting of 2DOF-PID controller in each area has been considered for design and analysis. Firstly, the proposed approach has been implemented in the aforementioned standard test system and thereafter, the robustness of the system consisting 2DOF-PID controller optimized by proposed technique has been estimated using the sensitivity analysis for the same. The robustness of the system consisting of 2DOF-PID controller optimized by proposed scheme is examined by varying the parameters of standard test system, loading conditions during operation, size and location of the disturbances. The performance of the 2DOF-PID controller optimized by proposed approach has also been compared with recently published approaches in the literature. The simulation results show that the proposed hGWOPS optimized 2DOF-PID controller shows far better performance than recently published approaches in the literature in terms of dynamic response. The simulation results also show that system performances hardly change when the operating load condition and system parameters are changed by ±50% from their nominal values, i.e. the proposed controllers are quite robust for a wide range of the system parameters and operating load conditions from their nominal values.
Nonlinear Decoupling PID Control Using Neural Networks and Multiple Models
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
For a class of complex industrial processes with strong nonlinearity, serious coupling and uncertainty, a nonlinear decoupling proportional-integral-differential (PID) controller is proposed, which consists of a traditional PID controller, a decoupling compensator and a feedforward compensator for the unmodeled dynamics. The parameters of such controller is selected based on the generalized minimum variance control law. The unmodeled dynamics is estimated and compensated by neural networks, a switching mechanism is introduced to improve tracking performance, then a nonlinear decoupling PID control algorithm is proposed. All signals in such switching system are globally bounded and the tracking error is convergent. Simulations show effectiveness of the algorithm.
Turbine speed control system based on a fuzzy-PID
Institute of Scientific and Technical Information of China (English)
SUN Jian-hua; WANG Wei; YU Hai-yan
2008-01-01
The flexibility demand of marine nuclear power plant is very high,the multiple parameters of the marine nuclear power plant with the once-through steam generator are strongly coupled,and the normal PID control of the turbine speed can't meet the control demand. This paper introduces a turbine speed Fuzzy-PID controller to coordinately control the steam pressure and thus realize the demand for quick tracking and steady state control over the turbine speed by using the Fuzzy control's quick dynamic response and PID control's steady state performance. The simulation shows the improvement of the response time and steady state performance of the control system.
PID control for chaotic synchronization using particle swarm optimization
Energy Technology Data Exchange (ETDEWEB)
Chang, W.-D. [Department of Computer and Communication, Shu-Te University, Kaohsiung 824, Taiwan (China)], E-mail: wdchang@mail.stu.edu.tw
2009-01-30
In this paper, we attempt to use the proportional-integral-derivative (PID) controller to achieve the chaos synchronization for delayed discrete chaotic systems. Three PID control gains can be optimally determined by means of using a novel optimization algorithm, called the particle swarm optimization (PSO). The algorithm is motivated from the organism behavior of fish schooling and bird flocking, and involves the social psychology principles in socio-cognition human agents and evolutionary computations. It has a good numerical convergence for solving optimization problem. To show the validity of the PSO-based PID control for chaos synchronization, several cases with different initial populations are considered and some simulation results are shown.
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.
一种柔性直流输电系统PID-ANFIS优化控制方法%A control method of PID-ANFIS controller for VSC-HVDC
Institute of Scientific and Technical Information of China (English)
杨天; 霍琳琳
2015-01-01
Due to the PI control system for VSC-HVDC has problems of parameters difficult to set, too many control users, and so on, a novel controller composed of PID function and multiple-output ANFIS (PID-ANFIS) is presented, which is made up of neural network, two order fuzzy control and PID control. A treble cooperative PSO (TCPSO) is also presented to optimize PID-ANFIS controller’s neural parameters. TCPSO is forged by harmonizing the grouping cooperation, the dimension-reduced cooperation and memory cooperation, which is able to improve the precision of optimizing neural networks. This paper provides the process of PID-ANFIS parameters training by TCPSO. Then, the TCPSO based PID-ANFIS controller performs the function of direct power control. The simulation results show that the controller presented has significant advantages of faster speed, smaller overshoot and better robustness by comparing to PI and it is a viable choice for VSC-HVDC control system.%针对柔性直流输电系统(Voltage Source Converter based High-Voltage Direct-Current, VSC-HVDC)双闭环控制中PI控制存在参数整定困难及控制器数量过多等问题，提出一种具有PID功能的自适应神经元模糊推理系统(Adaptive Neuro-Fuzzy Inference System with PID function, PID-ANFIS)控制器用于该系统控制。其中，PID-ANFIS控制器兼有神经网络控制、二阶模糊控制及PID功能；同时提出的基于三重合作粒子群算法(Treble Cooperative Particle Swarm Optimization, TCPSO)用于优化该控制器中神经网络参数。TCPSO采用由降维合作、分组合作与记忆合作组成的三重合作策略，极大程度上提升了神经网络参数优化的精度。深入研究了TCPSO优化PID-ANFIS控制器参数的步骤。基于TCPSO优化的PID-ANFIS控制器能够实现VSC-HVDC系统的直接功率控制效果。仿真结果表明该控制器具有控制速度快、超调量小、抗干扰能力强等优点，是VSC-HVDC控制系统的一个可行方案。
Neural PID Control Strategy for Networked Process Control
Directory of Open Access Journals (Sweden)
Jianhua Zhang
2013-01-01
Full Text Available A new method with a two-layer hierarchy is presented based on a neural proportional-integral-derivative (PID iterative learning method over the communication network for the closed-loop automatic tuning of a PID controller. It can enhance the performance of the well-known simple PID feedback control loop in the local field when real networked process control applied to systems with uncertain factors, such as external disturbance or randomly delayed measurements. The proposed PID iterative learning method is implemented by backpropagation neural networks whose weights are updated via minimizing tracking error entropy of closed-loop systems. The convergence in the mean square sense is analysed for closed-loop networked control systems. To demonstrate the potential applications of the proposed strategies, a pressure-tank experiment is provided to show the usefulness and effectiveness of the proposed design method in network process control systems.
IMC-PID design based on model matching approach and closed-loop shaping.
Jin, Qi B; Liu, Q
2014-03-01
Motivated by the limitations of the conventional internal model control (IMC), this communication addresses the design of IMC-based PID in terms of the robust performance of the control system. The IMC controller form is obtained by solving an H-infinity problem based on the model matching approach, and the parameters are determined by closed-loop shaping. The shaping of the closed-loop transfer function is considered both for the set-point tracking and for the load disturbance rejection. The design procedure is formulated as a multi-objective optimization problem which is solved by a specific optimization algorithm. A nice feature of this design method is that it permits a clear tradeoff between robustness and performance. Simulation examples show that the proposed method is effective and has a wide applicability.
Multiobjective optimization design of a fractional order PID controller for a gun control system.
Gao, Qiang; Chen, Jilin; Wang, Li; Xu, Shiqing; Hou, Yuanlong
2013-01-01
Motion control of gun barrels is an ongoing topic for the development of gun control equipments possessing excellent performances. In this paper, a typical fractional order PID control strategy is employed for the gun control system. To obtain optimal parameters of the controller, a multiobjective optimization scheme is developed from the loop-shaping perspective. To solve the specified nonlinear optimization problem, a novel Pareto optimal solution based multiobjective differential evolution algorithm is proposed. To enhance the convergent rate of the optimization process, an opposition based learning method is embedded in the chaotic population initialization process. To enhance the robustness of the algorithm for different problems, an adapting scheme of the mutation operation is further employed. With assistance of the evolutionary algorithm, the optimal solution for the specified problem is selected. The numerical simulation results show that the control system can rapidly follow the demand signal with high accuracy and high robustness, demonstrating the efficiency of the proposed controller parameter tuning method.
PID1 IS A NOVEL SENSITIZER OF BRAIN TUMOR CELLS TO CHEMOTHERAPY
Erdreich-Epstein, Anat; Xu, Jingying; Ren, Xiuhai
2014-01-01
BACKGROUND: PID1 is a phosphotyrosine binding domain-containing protein of unknown function in cancer. We recently provided the first report of PID1 in brain tumors (and in cancer). PID1 inhibits growth and proliferation and induces cell death, apoptosis and mitochondrial depolarization in glioblastoma, medulloblastoma and ATRT cell lines. PID1 siRNA had the opposite effect on mitochondrial depolarization. PID1 mRNA level was directly correlated with survival of patients with medulloblastoma ...
Research on Airborne Electro-Optical Tracking and Sighting System Based on Fuzzy PID and H∞ Control
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Airborne electro-optical tracking and sighting system is a three-degree-of-freedom angular position servo system which is influenced by multi-disturbance, and its control system consists of stabilizing and tracking components. Stabilizing control is applied to track angular velocity order and control multi-disturbance under airborne condition, and its robustness should be very good; tracking control is applied to compensate tracking error of angular position. A mathematical model is established by taking the control of yaw loop as example. H∞ stabilizing controller is designed by taking the advantage of H∞ control robustness and combining with Kalman filter. A fuzzy control is introduced in general PID control to design a decoupled fuzzy Smith estimating PID controller for tracking control. Simulation research shows that the control effect of airborne electro-optical tracking and sighting system based on fuzzy PID and H∞ control is good, especially when the model parameters change and the multi-disturbance exists, the system capability has little fall, but this system still can effectively track a target.
O'Dwyer, Aidan
1999-01-01
A summary of tuning rules for the PID control of single input, single output (SISO) processes with time delay, modeled in stable first order lag plus time delay (FOLPD) form, is provided in this part of the paper.
Bikash Dey; Lusika Roy
2014-01-01
This paper present three different control strategies based on PI Control, PID control and Two degree of freedom PID control for Continuous Stirred Tank Reactor (CSTR).CSTR which offers a diverse range of application in the field of chemical engineering as well as in the control engineering and is an attractive research area for process control researchers. Our objective is to control the temperature of CSTR in presence of the set point. MATLAB SIMULINK software is used for mo...
On the Conditional Distribution of the Multivariate $t$ Distribution
Ding, Peng
2016-01-01
As alternatives to the normal distributions, $t$ distributions are widely applied in robust analysis for data with outliers or heavy tails. The properties of the multivariate $t$ distribution are well documented in Kotz and Nadarajah's book, which, however, states a wrong conclusion about the conditional distribution of the multivariate $t$ distribution. Previous literature has recognized that the conditional distribution of the multivariate $t$ distribution also follows the multivariate $t$ ...
Karki, Hari Sharan; Barphagha, Inderjit Kaur; Ham, Jong Hyun
2012-09-01
Burkholderia glumae is a rice pathogenic bacterium that causes bacterial panicle blight. Some strains of this pathogen produce dark brown pigments when grown on casamino-acid peptone glucose (CPG) agar medium. A pigment-positive and highly virulent strain of B. glumae, 411gr-6, was randomly mutagenized with mini-Tn5gus, and the resulting mini-Tn5gus derivatives showing altered pigmentation phenotypes were screened on CPG agar plates to identify the genetic elements governing the pigmentation of B. glumae. In this study, a novel two-component regulatory system (TCRS) composed of the PidS sensor histidine kinase and the PidR response regulator was identified as an essential regulatory factor for pigmentation. Notably, the PidS/PidR TCRS was also required for the elicitation of the hypersensitive response on tobacco leaves, indicating the dependence of the hypersensitive response and pathogenicity (Hrp) type III secretion system of B. glumae on this regulatory factor. In addition, B. glumae mutants defective in the PidS/PidR TCRS showed less production of the phytotoxin, toxoflavin, and less virulence on rice panicles and onion bulbs relative to the parental strain, 411gr-6. The presence of highly homologous PidS and PidR orthologues in other Burkholderia species suggests that PidS/PidR-family TCRSs may exert the same or similar functions in different Burkholderia species, including both plant and animal pathogens.
Evaluation of multivariate surveillance
Frisén,Marianne; Andersson, Eva; Schiöler, Linus
2009-01-01
Multivariate surveillance is of interest in many areas such as industrial production, bioterrorism detection, spatial surveillance, and financial transaction strategies. Some of the suggested approaches to multivariate surveillance have been multivariate counterparts to the univariate Shewhart, EWMA, and CUSUM methods. Our emphasis is on the special challenges of evaluating multivariate surveillance methods. Some new measures are suggested and the properties of several measures are demonstrat...
Directory of Open Access Journals (Sweden)
N.Ramesh Raju
2015-10-01
Full Text Available PID controller is mostly used in process plants to control the system performance by properly choosing its parameters. The optimum PID parameters can be obtained in offline using genetic algorithm if the mathematical model of the system is exactly known. In all process plants the process parameters such as properties of materials like thermal conductivity, electrical conductivity, physical dimensions such as diameter, length of the pipes, parameters of valves and pumps will change as time runs. This happens due to corrosion, scaling, aging, repairs during the maintenance, wear and tear. When the system is robust these changes slightly affect the performance of the system. When the system is not robust they make the system performance worst. Due to above reasons the process plant parameters changes as time runs. It is not easy to measure the changes in system parameters while plant is running and could not be evaluated optimum PID parameters through mathematical model. In this paper a new approach using genetic algorithm and neural network is established for optimum self tuning of PID parameters by observing the time response of the system at any time while plant is running.
A novel multi-drive electric vehicle system control based on multi-input multi-output PID controller
Directory of Open Access Journals (Sweden)
Gasbaoui Brahim
2012-01-01
Full Text Available In-wheel-motor drive electric vehicle (EV is an innovative configuration of the modern EV, in which each wheel is driven individually by an electric motor. The classical traction motor control called the Independent Machine Control Structure (IMCS using a PID speed controller presents major inconveniences in modern EV safety, when the proposed control can not ensure stability of the EV with differing road topology and variations of speed. A new approach is proposed for a control of a two-in-wheel-motor drive EV, called the Maximum Control Structure MCS. This is based on a multivariable PID (MIMO-PID strategy, which is employed to estimate the linear speed error of each of the two back driving wheels, when the error of each wheel is taken into account in the other speed control computations. Simulation results show that the new control system presents increased safety for the EVs compared with the IMCS strategy and can maintain the error slip rate within the optimal range, ensuring the stability of the vehicle either in a straight or a curved line.
Fractional Order PID Control of Rotor Suspension by Active Magnetic Bearings
Directory of Open Access Journals (Sweden)
Parinya Anantachaisilp
2017-01-01
Full Text Available One of the key issues in control design for Active Magnetic Bearing (AMB systems is the tradeoff between the simplicity of the controller structure and the performance of the closed-loop system. To achieve this tradeoff, this paper proposes the design of a fractional order Proportional-Integral-Derivative (FOPID controller. The FOPID controller consists of only two additional parameters in comparison with a conventional PID controller. The feasibility of FOPID for AMB systems is investigated for rotor suspension in both the radial and axial directions. Tuning methods are developed based on the evolutionary algorithms for searching the optimal values of the controller parameters. The resulting FOPID controllers are then tested and compared with a conventional PID controller, as well as with some advanced controllers such as Linear Quadratic Gausian (LQG and H ∞ controllers. The comparison is made in terms of various stability and robustness specifications, as well as the dimensions of the controllers as implemented. Lastly, to validate the proposed method, experimental testing is carried out on a single-stage centrifugal compressor test rig equipped with magnetic bearings. The results show that, with a proper selection of gains and fractional orders, the performance of the resulting FOPID is similar to those of the advanced controllers.
Tuning of IMC based PID controllers for integrating systems with time delay.
Kumar, D B Santosh; Padma Sree, R
2016-07-01
Design of Proportional Integral and Derivative (PID) controllers based on IMC principles for various types of integrating systems with time delay is proposed. PID parameters are given in terms of process model parameters and a tuning parameter. The tuning parameter is IMC filter time constant. In the present work, the IMC filter (Q) is chosen in such a manner that the order of the denominator of IMC controller is one less than the order of the numerator. The IMC filter time constant (λ) is tuned in such a way that a good compromise is made between performance and robustness for both servo and regulatory problems. To improve servo response of the controller a set point filter is designed such that the closed loop response is similar to that of first order plus time delay system. The proposed controller design method is applied to various transfer function models and to the non-linear model equations of jacketed CSTR to demonstrate its applicability and effectiveness. The performance of the proposed controller is compared with the recently reported methods in terms of IAE and ITAE. The smooth functioning of the controller is determined in terms of total variation and compared with recently reported methods. Simulation studies are carried out on various integrating systems with time delay to show the effectiveness and superiority of the proposed controllers.
Split PID control: two sensors can be better than one
Znaimer, Leith
2014-01-01
The traditional proportional-integral-derivative (PID) algorithm for regulation suffers from a tradeoff: placing the sensor near the sample being regulated ensures that its steady-state temperature matches the desired setpoint. However, the propagation delay (lag) between heater and sample can limit the control bandwidth. Moving the sensor closer to the heater reduces the lag and increases the bandwidth but introduces offsets and drifts into the temperature of the sample. Here, we explore the consequences of using two probes---one near the heater, one near the sample---and assigning the integral term to the sample probe and the other terms to the heater probe. The \\textit{split-PID} algorithm can outperform PID control loops based on one sensor.
A General Method for Designing Fractional Order PID Controller
Directory of Open Access Journals (Sweden)
Marzieh Safaei
2013-01-01
Full Text Available The idea of using fractional order calculus in control became apparent when this kind of calculus was accepted as a powerful tool in many applications. This resulted in a new generation of PID controller called fractional order PID Controller, named as Controller. controller is more flexible and provides a better response with larger stability region as compared with standard PID controller. This paper presents a simple and reliable method for finding the family of controllers. The required calculations are done in frequency domain based on frequency response of the system and the stability region is specified in the parameters space. This method can be used for time-delay systems and, more generally, for any system with no transfer function.
Fractional order differentiation and robust control design crone, h-infinity and motion control
Sabatier, Jocelyn; Melchior, Pierre; Oustaloup, Alain
2015-01-01
This monograph collates the past decade’s work on fractional models and fractional systems in the fields of analysis, robust control and path tracking. Themes such as PID control, robust path tracking design and motion control methodologies involving fractional differentiation are amongst those explored. It juxtaposes recent theoretical results at the forefront in the field, and applications that can be used as exercises that will help the reader to assimilate the proposed methodologies. The first part of the book deals with fractional derivative and fractional model definitions, as well as recent results for stability analysis, fractional model physical interpretation, controllability, and H-infinity norm computation. It also presents a critical point of view on model pseudo-state and “real state”, tackling the problem of fractional model initialization. Readers will find coverage of PID, Fractional PID and robust control in the second part of the book, which rounds off with an extension of H-infinity ...
Multivariate analysis with LISREL
Jöreskog, Karl G; Y Wallentin, Fan
2016-01-01
This book traces the theory and methodology of multivariate statistical analysis and shows how it can be conducted in practice using the LISREL computer program. It presents not only the typical uses of LISREL, such as confirmatory factor analysis and structural equation models, but also several other multivariate analysis topics, including regression (univariate, multivariate, censored, logistic, and probit), generalized linear models, multilevel analysis, and principal component analysis. It provides numerous examples from several disciplines and discusses and interprets the results, illustrated with sections of output from the LISREL program, in the context of the example. The book is intended for masters and PhD students and researchers in the social, behavioral, economic and many other sciences who require a basic understanding of multivariate statistical theory and methods for their analysis of multivariate data. It can also be used as a textbook on various topics of multivariate statistical analysis.
PID controller tuning using the magnitude optimum criterion
Papadopoulos, Konstantinos
2014-01-01
An instructive reference that will help control researchers and engineers, interested in a variety of industrial processes, to take advantage of a powerful tuning method for the ever-popular PID control paradigm. This monograph presents explicit PID tuning rules for linear control loops regardless of process complexity. It shows the reader how such loops achieve zero steady-position, velocity, and acceleration errors and are thus able to track fast reference signals. The theoretical development takes place in the frequency domain by introducing a general-transfer-function-known process model
On PID Controller Design Using Knowledge Based Fuzzy System
Directory of Open Access Journals (Sweden)
Jana Nowakova
2012-01-01
Full Text Available The designing of PID controllers is a frequently discussed problem. Many of design methods have been developed, classic (analytical tuning methods, optimization methods etc. or not so common fuzzy knowledge based methods which are designed to achieve good setpoint following, corresponding time response etc. In this case, the new way of designing PID controller parameters is created where the above mentioned knowledge system based on relations of Ziegler-Nichols design methods is used, more precisely the combination of the both Ziegler-Nichols methods. The proof of efficiency of a proposed method and a numerical experiment is presented.
Nonlinear system PID-type multi-step predictive control
Institute of Scientific and Technical Information of China (English)
Yan ZHANG; Zengqiang CHEN; Zhuzhi YUAN
2004-01-01
A compound neural network was constructed during the process of identification and multi-step prediction. Under the PlD-type long-range predictive cost function, the control signal was calculated based on gradient algorithm. The nonlinear controller' s structure was similar to the conventional PID controller. The parameters of this controller were tuned by using a local recurrent neural network on-line. The controller has a better effect than the conventional PID controller. Simulation study shows the effectiveness and good performance.
Genetic Algorithm based PID controller for Frequency Regulation Ancillary services
Directory of Open Access Journals (Sweden)
Sandeep Bhongade
2010-12-01
Full Text Available In this paper, the parameters of Proportional, Integral and Derivative (PID controller for Automatic Generation Control (AGC suitable in restructured power system is tuned according to Generic Algorithms (GAs based performance indices. The key idea of the proposed method is to use the fitness function based on Area Control Error (ACE. The functioning of the proposed Genetic Algorithm based PID (GAPID controller has been demonstrated on a 75-bus Indian power system network and the results have been compared with those obtained by using Least Square Minimization method.
Sharma, Richa; Gaur, Prerna; Mittal, A P
2015-09-01
The robotic manipulators are multi-input multi-output (MIMO), coupled and highly nonlinear systems. The presence of external disturbances and time-varying parameters adversely affects the performance of these systems. Therefore, the controller designed for these systems should effectively deal with such complexities, and it is an intriguing task for control engineers. This paper presents two-degree of freedom fractional order proportional-integral-derivative (2-DOF FOPID) controller scheme for a two-link planar rigid robotic manipulator with payload for trajectory tracking task. The tuning of all controller parameters is done using cuckoo search algorithm (CSA). The performance of proposed 2-DOF FOPID controllers is compared with those of their integer order designs, i.e., 2-DOF PID controllers, and with the traditional PID controllers. In order to show effectiveness of proposed scheme, the robustness testing is carried out for model uncertainties, payload variations with time, external disturbance and random noise. Numerical simulation results indicate that the 2-DOF FOPID controllers are superior to their integer order counterparts and the traditional PID controllers.
PID Controller Stabilization for First-order Integral Processes with Time Delay
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Due to the widespread application of the PID controller in industrial control systems, it is desirable to know the complete set of all the stabilizing PID controllers for a given plant before the controller design and tuning. In this paper,the stabilization problems of the classical proportionalintegral-derivative (PID) controller and the singleparameter PID controller (containing only one adjustable parameter) for integral processes with time delay are investigated, respectively. The complete set of stabilizing parameters of the classical PID controller is determined using a version of the Hermite-Biehler Theorem applicable to quasipolynomials. Since the stabilization problem of the single-parameter PID controller cannot be treated by the Hermite-Biehler Theorem, a simple method called duallocus diagram is employed to derive the stabilizing range of the single-parameter PID controller. These results provide insight into the tuning of the PID controllers.
Genetic Algorithm Based PID Controller Tuning Approach for Continuous Stirred Tank Reactor
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A. Jayachitra
2014-01-01
Full Text Available Genetic algorithm (GA based PID (proportional integral derivative controller has been proposed for tuning optimized PID parameters in a continuous stirred tank reactor (CSTR process using a weighted combination of objective functions, namely, integral square error (ISE, integral absolute error (IAE, and integrated time absolute error (ITAE. Optimization of PID controller parameters is the key goal in chemical and biochemical industries. PID controllers have narrowed down the operating range of processes with dynamic nonlinearity. In our proposed work, globally optimized PID parameters tend to operate the CSTR process in its entire operating range to overcome the limitations of the linear PID controller. The simulation study reveals that the GA based PID controller tuned with fixed PID parameters provides satisfactory performance in terms of set point tracking and disturbance rejection.
Performance Analysis of a Neuro-PID Controller Applied to a Robot Manipulator
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Saeed Pezeshki
2012-11-01
Full Text Available The performance of robot manipulators with nonadaptive controllers might degrade significantly due to the open loop unstable system and the effect of some uncertainties on the robot model or environment. A novel Neural Network PID controller (NNP is proposed in order to improve the system performance and its robustness. The Neural Network (NN technique is applied to compensate for the effect of the uncertainties of the robot model. With the NN compensator introduced, the system errors and the NN weights with large dispersion are guaranteed to be bounded in the Lyapunov sense. The weights of the NN compensator are adaptively tuned. The simulation results show the effectiveness of the model validation approach and its efficiency to guarantee a stable and accurate trajectory tracking process in the presence of uncertainties.
Design of Dual Axis Laser Scanning Diameter Measuring Gauge System with PID Co
Institute of Scientific and Technical Information of China (English)
LI Xin-qiu; LI Zhi-wei; LIU Da-jiang
2009-01-01
Dual axis laser scanning diameter measuring gauge system(DALSDMGS)with PID controller,which can be used for online non-contact diameter measuring and control on the hose,wire and rod production line,is introduced.The measure principle and implementation of this system are also presented.A PID control module with PID parameters tuning is included in the measuring and control system,which functions as a PID automatic controller of the diameter.
Directory of Open Access Journals (Sweden)
Bikash Dey
2014-01-01
Full Text Available This paper present three different control strategies based on PI Control, PID control and Two degree of freedom PID control for Continuous Stirred Tank Reactor (CSTR.CSTR which offers a diverse range of application in the field of chemical engineering as well as in the control engineering and is an attractive research area for process control researchers. Our objective is to control the temperature of CSTR in presence of the set point. MATLAB SIMULINK software is used for model design and simulation
Multivariate Voronoi Outlier Detection for Time Series.
Zwilling, Chris E; Wang, Michelle Yongmei
2014-10-01
Outlier detection is a primary step in many data mining and analysis applications, including healthcare and medical research. This paper presents a general method to identify outliers in multivariate time series based on a Voronoi diagram, which we call Multivariate Voronoi Outlier Detection (MVOD). The approach copes with outliers in a multivariate framework, via designing and extracting effective attributes or features from the data that can take parametric or nonparametric forms. Voronoi diagrams allow for automatic configuration of the neighborhood relationship of the data points, which facilitates the differentiation of outliers and non-outliers. Experimental evaluation demonstrates that our MVOD is an accurate, sensitive, and robust method for detecting outliers in multivariate time series data.
DEFF Research Database (Denmark)
Gorm Hansen, Birgitte
2012-01-01
as the analytical framework for descri bing the complex relationship between academic science and its so called “external” habitat. Although relational skills and adaptability do seem to be at the heart of successful research management, the key to success does not lie with the ability to assimilate to industrial...... knowledge", Danish research policy seems to have helped develop politically and economically "robust scientists". Scientific robustness is acquired by way of three strategies: 1) tasting and discriminating between resources so as to avoid funding that erodes academic profiles and push scientists away from...... and industrial intere sts. The paper concludes by stressing the potential danger of policy habitats who have promoted the evolution of robust scientists based on a competitive system where only the fittest survive. Robust scientists, it is argued, have the potential to become a new “invasive species...
Robust procedures in chemometrics
DEFF Research Database (Denmark)
Kotwa, Ewelina
-way chemometrical methods, such as PCA and PARAFAC models for analysing spatial and depth profiles of sea water samples, defined by three data modes: depth, variables and geographical location. Emphasis was also put on predicting fluorescence values, as being a natural measure of biological activity, by applying....... applying a multivariate and multi-way data analytical frame-work in fields where less sophisticated data analysis methods are currently used, and 2. developing new, more robust alternatives to already existing multivariate tools. The first part of the study was realised by applying two- and three...... and comparing the Partial Least Squares (PLS) regression technique with its multi-way alternative, N-PLS. Results of the analysis indicated superiority of the three-way frame-work, potentially constituting a novel assessment of the sea water measurements. Particularly in the case of regression models...
Switching Between Multivariable Controllers
DEFF Research Database (Denmark)
Niemann, H.; Stoustrup, Jakob; Abrahamsen, R.B.
2004-01-01
A concept for implementation of multivariable controllers is presented in this paper. The concept is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization of all stabilizing controllers. By using this architecture for implementation of multivariable controllers, it is shown how...
DEFF Research Database (Denmark)
Silvennoinen, Annastiina; Teräsvirta, Timo
This article contains a review of multivariate GARCH models. Most common GARCH models are presented and their properties considered. This also includes nonparametric and semiparametric models. Existing specification and misspecification tests are discussed. Finally, there is an empirical example...... in which several multivariate GARCH models are fitted to the same data set and the results compared....
Multivariate irregular sampling theorem
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
In this paper,we prove a Marcinkiewicz-Zygmund type inequality for multivariate entire functions of exponential type with non-equidistant spaced sampling points. And from this result,we establish a multivariate irregular Whittaker-Kotelnikov-Shannon type sampling theorem.
DEFF Research Database (Denmark)
Silvennoinen, Annastiina; Teräsvirta, Timo
This article contains a review of multivariate GARCH models. Most common GARCH models are presented and their properties considered. This also includes nonparametric and semiparametric models. Existing specification and misspecification tests are discussed. Finally, there is an empirical example...... in which several multivariate GARCH models are fitted to the same data set and the results compared....
Multivariate irregular sampling theorem
Institute of Scientific and Technical Information of China (English)
CHEN GuangGui; FANG GenSun
2009-01-01
In this paper, we prove a Marcinkiewicz-Zygmund type inequality for multivariate entire functions of exponential type with non-equidistant spaced sampling points. And from this result, we establish a multivariate irregular Whittaker-Kotelnikov-Shannon type sampling theorem.
Switching Between Multivariable Controllers
DEFF Research Database (Denmark)
Niemann, Hans Henrik; Stoustrup, Jakob; Abrahamsen, Rune
2004-01-01
it is possible to smoothly switch between multivariable controllers with guaranteed closed-loop stability. This includes also the case where one or more controllers are unstable. The concept for smooth online changes of multivariable controllers based on the YJBK architecture can also handle the start up...
PID control of second-order system with hysteresis
Jayawardhana, B.; Logemann, H.; Ryan, E.P.
2007-01-01
The efficacy of proportional, derivative and integral (PID) control for set point regulation and disturbance rejection is investigated in a context of mechanical systems with hysteretic components. Two basic structures are studied: in the first, the hysteretic component resides (internally) in the r
PID control of second-order systems with hysteresis
Jayawardhana, Bayu; Logemann, Hartmut; Ryan, Eugene P.
2008-01-01
The efficacy of proportional, integral and derivative (PID) control for set point regulation and disturbance rejection is investigated in a context of second-order systems with hysteretic components. Two basic structures are studied: in the first, the hysteretic component resides (internally) in the
All About PID - Testing and Avoidance in the Field
Energy Technology Data Exchange (ETDEWEB)
Hacke, Peter; Johnston, Steve
2016-09-01
Potential-induced degradation can cause significant power loss in modules if the appropriate precautions are not taken. In the first part of a new series in PV Tech Power on module failure, Peter Hacke and Steve Johnston assess the current state-of-the-art in detecting, avoiding and mitigating the worst effects of PID.
Design of a PID Controller for a PCR Micro Reactor
Dinca, M. P.; Gheorghe, M.; Galvin, P.
2009-01-01
Proportional-integral-derivative (PID) controllers are widely used in process control, and consequently they are described in most of the textbooks on automatic control. However, rather than presenting the overall design process, the examples given in such textbooks are intended to illuminate specific focused aspects of selection, tuning and…
Integrated Auto-Tuning PID Control of Continuous Casting Process
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
PID controllers were used for the hydraulic servo system of sliding gate and the tundish weight control system in continuous caster. These two loops were synthesized in mould level controller based on model reduction and internal model control strategy. Satisfactory control performance of this synthetic mould level controller was demonstrated by simulations and on-line experiments.
PID motion control tuning rules in a damping injection framework
Tadele, Tadele Shiferaw; Vries, de Theo; Stramigioli, Stefano
2013-01-01
This paper presents a general design approach for a performance based tuning of a damping injection framework impedance controller by using insights from PID motion control tuning rules. The damping injection framework impedance controller is suitable for human friendly robots as it enhances safety
Comparative Analysis of PSO Algorithms for PID Controller Tuning
Institute of Scientific and Technical Information of China (English)
ŠTIMAC Goranka; BRAUT Sanjin; ŽIGULIĆRoberto
2014-01-01
The active magnetic bearing(AMB) suspends the rotating shaft and maintains it in levitated position by applying controlled electromagnetic forces on the rotor in radial and axial directions. Although the development of various control methods is rapid, PID control strategy is still the most widely used control strategy in many applications, including AMBs. In order to tune PID controller, a particle swarm optimization(PSO) method is applied. Therefore, a comparative analysis of particle swarm optimization(PSO) algorithms is carried out, where two PSO algorithms, namely (1) PSO with linearly decreasing inertia weight(LDW-PSO), and (2) PSO algorithm with constriction factor approach(CFA-PSO), are independently tested for different PID structures. The computer simulations are carried out with the aim of minimizing the objective function defined as the integral of time multiplied by the absolute value of error(ITAE). In order to validate the performance of the analyzed PSO algorithms, one-axis and two-axis radial rotor/active magnetic bearing systems are examined. The results show that PSO algorithms are effective and easily implemented methods, providing stable convergence and good computational efficiency of different PID structures for the rotor/AMB systems. Moreover, the PSO algorithms prove to be easily used for controller tuning in case of both SISO and MIMO system, which consider the system delay and the interference among the horizontal and vertical rotor axes.
Comparative analysis of PSO algorithms for PID controller tuning
Štimac, Goranka; Braut, Sanjin; Žigulić, Roberto
2014-09-01
The active magnetic bearing(AMB) suspends the rotating shaft and maintains it in levitated position by applying controlled electromagnetic forces on the rotor in radial and axial directions. Although the development of various control methods is rapid, PID control strategy is still the most widely used control strategy in many applications, including AMBs. In order to tune PID controller, a particle swarm optimization(PSO) method is applied. Therefore, a comparative analysis of particle swarm optimization(PSO) algorithms is carried out, where two PSO algorithms, namely (1) PSO with linearly decreasing inertia weight(LDW-PSO), and (2) PSO algorithm with constriction factor approach(CFA-PSO), are independently tested for different PID structures. The computer simulations are carried out with the aim of minimizing the objective function defined as the integral of time multiplied by the absolute value of error(ITAE). In order to validate the performance of the analyzed PSO algorithms, one-axis and two-axis radial rotor/active magnetic bearing systems are examined. The results show that PSO algorithms are effective and easily implemented methods, providing stable convergence and good computational efficiency of different PID structures for the rotor/AMB systems. Moreover, the PSO algorithms prove to be easily used for controller tuning in case of both SISO and MIMO system, which consider the system delay and the interference among the horizontal and vertical rotor axes.
Modeling and Implementation of PID Control for Autonomous Robots
2007-06-01
Richard Dorf . Modern Control Systems. New York, New York: Addison-Wesley Publishing, 1995. Cabezas, Rodrigo. Design of A Bore Sight Camera For The...IMPLEMENTATION OF PID CONTROL FOR AUTONOMOUS ROBOTS by Todd A. Williamson June 2007 Thesis Advisor: Richard Harkins Second Reader: Peter...Author: Todd A. Williamson Approved by: Richard Harkins Thesis Advisor Peter Crooker Second Reader James Luscombe
PID 参数工程整定方法研究%Study of PID parameters adjust method
Institute of Scientific and Technical Information of China (English)
许雪
2016-01-01
This article analyzes the effect of proportion , integrate and differential control in the PID control model, introduces traditional PID parameter tuning methods, and summarizes the PID parameter empirical tuning methods, depending on the method of falling film evaporator flow level cascade control system, the main theme and the sub-tune PID parameters can be adjusted , the result indicates that the System can control the process of production smoothly.%本文分析了PID控制模型中比例积分微分的作用，介绍了传统PID参数整定的方法，并总结了PID参数经验整定方法，应用该方法对碱液降膜蒸发流量液位串级控制系统主调和副调PID参数进行调整，并取得了较稳定的控制效果。
PID design based on Maclaurin expansion and its model-free auto-tuning%基于Maclaurin展开的PID设计与无模型自整定
Institute of Scientific and Technical Information of China (English)
杨启文; 阳外玲; 薛云灿; 余福祥; 杨远慧
2011-01-01
针对自衡对象,提出一种基于期望模型的PID自整定方法,该方法无需被控对象的数学模型.利用Maclaurin腱开技术,给出了PID控制器的整定公式:并通过开环阶跃响应,实现了PID控制器的无模型白整定.仿真结果表明,利用该自整定方法所得的PID能有效地提高高阶被控对象的系统性能;即使在噪声环境下,该方法仍具有很好的鲁棒性.%A method of auto-tuning for PID controller based on the desired model is presented for the stable plant in this paper. No model of controlled plants is needed by using the proposed method. The tuning of PID controller is formulated by using the Maclaurin expansion. The model-free auto-tuning of PID controller is implemented during the open loop step response. Simulation results show that the resulting PID controller is capable of enhancing the control performance for high-order plant effectively, and the proposed method has a strong robustness even under noise condition.
Application of fuzzy logic controller with self-tuning PID parameters%PID参数自整定模糊控制器的应用
Institute of Scientific and Technical Information of China (English)
李付举
2011-01-01
In view of electrical heating furnace's non-linear control object characteristics of large inertia, pure time-delay and parameters time-variation and the hard-to-tune characteristic of conventional PID control parameter, a new method for fuzzy control with self-tuning PID parameters was put forward. A fuzzy controller with self-tuning PID parameters was designed and applied in the furnace's temperature control system. The result shows that fuzzy control with self-ttming PID parameters eliminates the system's steady state error, has neither overshoot nor oscillation but great robustness, and is easily handled; therefore it is of some practical value.%针对电加热炉大惯性、纯滞后、参数时变的非线性对象的控制的特点,以及常规PID控制参数不易调节的特点,提出了一种PID参数自整定模糊控制方法,设计了PID参数自整定模糊控制器,并在炉温控制系统中应用.实验结果表明:PID参数自整定模糊控制消除了系统的稳态误差,没有超调和振荡,鲁棒性较强,而且简单易行,具有一定的实用价值.
Methods of Multivariate Analysis
Rencher, Alvin C
2012-01-01
Praise for the Second Edition "This book is a systematic, well-written, well-organized text on multivariate analysis packed with intuition and insight . . . There is much practical wisdom in this book that is hard to find elsewhere."-IIE Transactions Filled with new and timely content, Methods of Multivariate Analysis, Third Edition provides examples and exercises based on more than sixty real data sets from a wide variety of scientific fields. It takes a "methods" approach to the subject, placing an emphasis on how students and practitioners can employ multivariate analysis in real-life sit
Design of Adaptive Fuzzy PID Altitude Control System for Unmanned Aerial Vehicle
Institute of Scientific and Technical Information of China (English)
SHI Gang; YANG Shu-xing; JING Ya-xing; XU Yong
2008-01-01
Based on Matlab/Simulink and Fuzzy Logic toolboxes, the altitude control system is designed and simulated. The validity of conventional PID control method and adaptive fuzzy PID control method is compared. It can be drawn out that the adaptive fuzzy PID control method is superior to the conventional PID in rising time and overshoot etc. The effectiveness of a fuzzy PID controller shows potential application in the future, especially in the presence of model uncertainty or changing dynamics and time-varying parameters.
Hybrid PID and PSO-based control for electric power assist steering system for electric vehicle
Hanifah, R. A.; Toha, S. F.; Ahmad, S.
2013-12-01
Electric power assist steering (EPAS) system provides an important significance in enhancing the driving performance of a vehicle with its energy-conserving features. This paper presents a hybrid PID (Proportional-Integral-Derivative) and particle swarm optimization (PSO) based control scheme to minimize energy consumption for EPAS. This single objective optimization scheme is realized using the PSO technique in searching for best gain parameters of the PID controller. The fast tuning feature of this optimum PID controller produced high-quality solutions. Simulation results show the performance and effectiveness of the hybrid PSO-PID based controller as opposed to the conventional PID controller.
Energy Technology Data Exchange (ETDEWEB)
Oh, Jaewon; Dahal, Som; Dauksher, Bill; Bowden, Stuart; Tamizhmani, Govindasamy; Hacke, Peter
2016-11-21
Various characterization techniques have historically been developed in order to screen potential induced degradation (PID)-susceptible cells, but those techniques require final solar cells. We present a new characterization technique for screening PID-susceptible cells during the cell fabrication process. Illuminated Lock-In Thermography (ILIT) was used to image PID shunting of the cell without metallization and clearly showed PID-affected areas. PID-susceptible cells can be screened by ILIT, and the sample structure can advantageously be simplified as long as the sample has the silicon nitride antireflection coating and an aluminum back surface field.
连续搅拌反应釜过程的闭环增益成形PID控制器设计%PID controller design of closed-loop gain shaping in CSTR process
Institute of Scientific and Technical Information of China (English)
李述清; 张胜修; 张煜东; 胡波
2011-01-01
针对连续搅拌反应釜(CSTR)系统控制问题,设计了一种基于闭环增益成形算法的PID控制器,以提高PID控制器设计的简洁性和鲁棒性.首先假设期望闭环回路传递函数有一阶形式,同时将受控对象的一阶传递函数和PID控制器构成实际闭环回路传递函数.然后,比较期望闭环回路传递函数和实际闭环回路传递函数,即可确定PJD参数.最后,以某CSTR系统为例,利用该方法设计了PID控制器,并通过仿真结果比较,检验了该方法所得PID控制器的良好鲁棒稳定性和动态品质.%To solve the control problem of Continuous-Stirred-Tank-Reactor (CSTR), a straightforward PID design based on closed-loop gain shaping algorithm was proposed in this paper to enhance the simplicity and robustness of PID controller.Firstly, the transfer function of the anticipant closed-loop control system was assumed as a 1st order system, and the actual closed-loop transfer function was consisted of the 1 st order transfer function and PID controller.Then, the anticipated closedloop transfer function was compared with that of the actual closed-loop, thus the PID controller coefficients could be calculated.Finally, the robust PID controller was designed in a CSTR system.The simulation results demonstrate that the PID controller has better robust stability and dynamic performance.
Multivariate Time Series Search
National Aeronautics and Space Administration — Multivariate Time-Series (MTS) are ubiquitous, and are generated in areas as disparate as sensor recordings in aerospace systems, music and video streams, medical...
Robust Multivariable Controller Design via Implicit Model-Following Methods.
1983-12-01
16, the "uncertainties" of nonlinearities and higher-order actuator dynamics are, in fact, a reality ; the controller must work despite them. The...82172799- END IF B-23 2910m PRINT’, ’ENTER NUMBER OF AUMENTED DESIGN STATES: 28118 READ#, INON 2929. PaIr., ’ENTER NUMBER OF DISTURBANCE STATES IN DESIGN
Institute of Scientific and Technical Information of China (English)
张燕; 陈增强; 杨鹏; 袁著祉
2004-01-01
A nonlinear proportional-integral-derivative (PID) controller is constructed based on recurrent neural networks. In the control process of nonlinear multivariable systems, several nonlinear PID controllers have been adopted in parallel. Under the decoupling cost function, a decoupling control strategy is proposed. Then the stability condition of the controller is presented based on the Lyapunov theory. Simulation examples are given to show effectiveness of the proposed decoupling control.
Two-level tuning of fuzzy PID controllers.
Mann, G I; Hu, B G; Gosine, R G
2001-01-01
Fuzzy PID tuning requires two stages of tuning; low level tuning followed by high level tuning. At the higher level, a nonlinear tuning is performed to determine the nonlinear characteristics of the fuzzy output. At the lower level, a linear tuning is performed to determine the linear characteristics of the fuzzy output for achieving overall performance of fuzzy control. First, different fuzzy systems are defined and then simplified for two-point control. Non-linearity tuning diagrams are constructed for fuzzy systems in order to perform high level tuning. The linear tuning parameters are deduced from the conventional PID tuning knowledge. Using the tuning diagrams, high level tuning heuristics are developed. Finally, different applications are demonstrated to show the validity of the proposed tuning method.
Tuning PID Controller Using Multiobjective Ant Colony Optimization
Directory of Open Access Journals (Sweden)
Ibtissem Chiha
2012-01-01
Full Text Available This paper treats a tuning of PID controllers method using multiobjective ant colony optimization. The design objective was to apply the ant colony algorithm in the aim of tuning the optimum solution of the PID controllers (Kp, Ki, and Kd by minimizing the multiobjective function. The potential of using multiobjective ant algorithms is to identify the Pareto optimal solution. The other methods are applied to make comparisons between a classic approach based on the “Ziegler-Nichols” method and a metaheuristic approach based on the genetic algorithms. Simulation results demonstrate that the new tuning method using multiobjective ant colony optimization has a better control system performance compared with the classic approach and the genetic algorithms.
An improved PID switching control strategy for type 1 diabetes.
Marchetti, Gianni; Barolo, Massimiliano; Jovanovic, Lois; Zisser, Howard; Seborg, Dale E
2008-03-01
In order for an "artificial pancreas" to become a reality for ambulatory use, a practical closed-loop control strategy must be developed and validated. In this paper, an improved PID control strategy for blood glucose control is proposed and critically evaluated in silico using a physiologic model of Hovorka et al. [1]. The key features of the proposed control strategy are: 1) a switching strategy for initiating PID control after a meal and insulin bolus; 2) a novel time-varying setpoint trajectory; 3) noise and derivative filters to reduce sensitivity to sensor noise; and 4) a practical controller tuning strategy. Simulation results demonstrate that proposed control strategy compares favorably to alternatives for realistic conditions that include meal challenges, incorrect carbohydrate meal estimates, changes in insulin sensitivity, and measurement noise.
Neural Network Based PID Gain Tuning of Chemical Plant Controller
Abe, Yoshihiro; Konishi, Masami; Imai, Jun; Hasegawa, Ryusaku; Watanabe, Masamori; Kamijo, Hiroaki
In these years, plant control systems are highly automated and applied to many industries. The control performances change with the passage of time, because of the deterioration of plant facilities. This is why human experts tune the control system to improve the total plant performances. In this study, PID control system for the oil refining chemical plant process is treated. In oil refining, there are thousands of the control loops in the plant to keep the product quality at the desired value and to secure the safety of the plant operation. According to the ambiguity of the interference between control loops, it is difficult to estimate the plant dynamical model accurately. Using neuro emulator and recurrent neural networks model (RNN model) for emulation and tuning parameters, PID gain tuning system of chemical plant controller is constructed. Through numerical experiments using actual plant data, effect of the proposed method was ascertained.
Active structural control with stable fuzzy PID techniques
Yu, Wen
2016-01-01
This book presents a detailed discussion of intelligent techniques to measure the displacement of buildings when they are subjected to vibration. It shows how these techniques are used to control active devices that can reduce vibration 60–80% more effectively than widely used passive anti-seismic systems. After introducing various structural control devices and building-modeling and active structural control methods, the authors propose offset cancellation and high-pass filtering techniques to solve some common problems of building-displacement measurement using accelerometers. The most popular control algorithms in industrial settings, PD/PID controllers, are then analyzed and then combined with fuzzy compensation. The stability of this combination is proven with standard weight-training algorithms. These conditions provide explicit methods for selecting PD/PID controllers. Finally, fuzzy-logic and sliding-mode control are applied to the control of wind-induced vibration. The methods described are support...
Banerjee, S; Grebogi, C; Banerjee, Soumitro; Yorke, James A.; Grebogi, Celso
1998-01-01
It has been proposed to make practical use of chaos in communication, in enhancing mixing in chemical processes and in spreading the spectrum of switch-mode power suppies to avoid electromagnetic interference. It is however known that for most smooth chaotic systems, there is a dense set of periodic windows for any range of parameter values. Therefore in practical systems working in chaotic mode, slight inadvertent fluctuation of a parameter may take the system out of chaos. We say a chaotic attractor is robust if, for its parameter values there exists a neighborhood in the parameter space with no periodic attractor and the chaotic attractor is unique in that neighborhood. In this paper we show that robust chaos can occur in piecewise smooth systems and obtain the conditions of its occurrence. We illustrate this phenomenon with a practical example from electrical engineering.
Improving the pneumatic control valve performance using a PID controller
Heidari, Mohammad; Homaei, Hadi
2014-01-01
Pneumatic control valves are still the most used in process industries due to their low cost and simplicity. This paper presents a design procedure of a PID controller for a pneumatic control valve. For comparison, P and PI controllers are also utilized for the control valve. The bond graph method is used to model the control valve, in order to compare the response characteristics of the valve. Simulation results are found for three controllers of the valve. The integral time absolute error c...
Adaptive PID control based on orthogonal endocrine neural networks.
Milovanović, Miroslav B; Antić, Dragan S; Milojković, Marko T; Nikolić, Saša S; Perić, Staniša Lj; Spasić, Miodrag D
2016-12-01
A new intelligent hybrid structure used for online tuning of a PID controller is proposed in this paper. The structure is based on two adaptive neural networks, both with built-in Chebyshev orthogonal polynomials. First substructure network is a regular orthogonal neural network with implemented artificial endocrine factor (OENN), in the form of environmental stimuli, to its weights. It is used for approximation of control signals and for processing system deviation/disturbance signals which are introduced in the form of environmental stimuli. The output values of OENN are used to calculate artificial environmental stimuli (AES), which represent required adaptation measure of a second network-orthogonal endocrine adaptive neuro-fuzzy inference system (OEANFIS). OEANFIS is used to process control, output and error signals of a system and to generate adjustable values of proportional, derivative, and integral parameters, used for online tuning of a PID controller. The developed structure is experimentally tested on a laboratory model of the 3D crane system in terms of analysing tracking performances and deviation signals (error signals) of a payload. OENN-OEANFIS performances are compared with traditional PID and 6 intelligent PID type controllers. Tracking performance comparisons (in transient and steady-state period) showed that the proposed adaptive controller possesses performances within the range of other tested controllers. The main contribution of OENN-OEANFIS structure is significant minimization of deviation signals (17%-79%) compared to other controllers. It is recommended to exploit it when dealing with a highly nonlinear system which operates in the presence of undesirable disturbances.
Tuning of PID controllers for boiler-turbine units.
Tan, Wen; Liu, Jizhen; Fang, Fang; Chen, Yanqiao
2004-10-01
A simple two-by-two model for a boiler-turbine unit is demonstrated in this paper. The model can capture the essential dynamics of a unit. The design of a coordinated controller is discussed based on this model. A PID control structure is derived, and a tuning procedure is proposed. The examples show that the method is easy to apply and can achieve acceptable performance.
Vision-Based Robot Following Using PID Control
Directory of Open Access Journals (Sweden)
Chandra Sekhar Pati
2017-06-01
Full Text Available Applications like robots which are employed for shopping, porter services, assistive robotics, etc., require a robot to continuously follow a human or another robot. This paper presents a mobile robot following another tele-operated mobile robot based on a PID (Proportional–Integral-Differential controller. Here, we use two differential wheel drive robots; one is a master robot and the other is a follower robot. The master robot is manually controlled and the follower robot is programmed to follow the master robot. For the master robot, a Bluetooth module receives the user’s command from an android application which is processed by the master robot’s controller, which is used to move the robot. The follower robot receives the image from the Kinect sensor mounted on it and recognizes the master robot. The follower robot identifies the x, y positions by employing the camera and the depth by using the Kinect depth sensor. By identifying the x, y, and z locations of the master robot, the follower robot finds the angle and distance between the master and follower robot, which is given as the error term of a PID controller. Using this, the follower robot follows the master robot. A PID controller is based on feedback and tries to minimize the error. Experiments are conducted for two indigenously developed robots; one depicting a humanoid and the other a small mobile robot. It was observed that the follower robot was easily able to follow the master robot using well-tuned PID parameters.
Čίžek, Pavel; Härdle, Wolfgang Karl
2006-01-01
Econometrics often deals with data under, from the statistical point of view, non-standard conditions such as heteroscedasticity or measurement errors and the estimation methods need thus be either adopted to such conditions or be at least insensitive to them. The methods insensitive to violation of certain assumptions, for example insensitive to the presence of heteroscedasticity, are in a broad sense referred to as robust (e.g., to heteroscedasticity). On the other hand, there is also a mor...
Multivariate generalized linear mixed models using R
Berridge, Damon Mark
2011-01-01
Multivariate Generalized Linear Mixed Models Using R presents robust and methodologically sound models for analyzing large and complex data sets, enabling readers to answer increasingly complex research questions. The book applies the principles of modeling to longitudinal data from panel and related studies via the Sabre software package in R. A Unified Framework for a Broad Class of Models The authors first discuss members of the family of generalized linear models, gradually adding complexity to the modeling framework by incorporating random effects. After reviewing the generalized linear model notation, they illustrate a range of random effects models, including three-level, multivariate, endpoint, event history, and state dependence models. They estimate the multivariate generalized linear mixed models (MGLMMs) using either standard or adaptive Gaussian quadrature. The authors also compare two-level fixed and random effects linear models. The appendices contain additional information on quadrature, model...
Simplicial band depth for multivariate functional data
López-Pintado, Sara
2014-03-05
We propose notions of simplicial band depth for multivariate functional data that extend the univariate functional band depth. The proposed simplicial band depths provide simple and natural criteria to measure the centrality of a trajectory within a sample of curves. Based on these depths, a sample of multivariate curves can be ordered from the center outward and order statistics can be defined. Properties of the proposed depths, such as invariance and consistency, can be established. A simulation study shows the robustness of this new definition of depth and the advantages of using a multivariate depth versus the marginal depths for detecting outliers. Real data examples from growth curves and signature data are used to illustrate the performance and usefulness of the proposed depths. © 2014 Springer-Verlag Berlin Heidelberg.
Optimal Pid Controller Design Using Adaptive Vurpso Algorithm
Zirkohi, Majid Moradi
2015-04-01
The purpose of this paper is to improve theVelocity Update Relaxation Particle Swarm Optimization algorithm (VURPSO). The improved algorithm is called Adaptive VURPSO (AVURPSO) algorithm. Then, an optimal design of a Proportional-Integral-Derivative (PID) controller is obtained using the AVURPSO algorithm. An adaptive momentum factor is used to regulate a trade-off between the global and the local exploration abilities in the proposed algorithm. This operation helps the system to reach the optimal solution quickly and saves the computation time. Comparisons on the optimal PID controller design confirm the superiority of AVURPSO algorithm to the optimization algorithms mentioned in this paper namely the VURPSO algorithm, the Ant Colony algorithm, and the conventional approach. Comparisons on the speed of convergence confirm that the proposed algorithm has a faster convergence in a less computation time to yield a global optimum value. The proposed AVURPSO can be used in the diverse areas of optimization problems such as industrial planning, resource allocation, scheduling, decision making, pattern recognition and machine learning. The proposed AVURPSO algorithm is efficiently used to design an optimal PID controller.
Design of PID Controller Simulator based on Genetic Algorithm
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Fahri VATANSEVER
2013-08-01
Full Text Available PID (Proportional Integral and Derivative controllers take an important place in the field of system controlling. Various methods such as Ziegler-Nichols, Cohen-Coon, Chien Hrones Reswick (CHR and Wang-Juang-Chan are available for the design of such controllers benefiting from the system time and frequency domain data. These controllers are in compliance with system properties under certain criteria suitable to the system. Genetic algorithms have become widely used in control system applications in parallel to the advances in the field of computer and artificial intelligence. In this study, PID controller designs have been carried out by means of classical methods and genetic algorithms and comparative results have been analyzed. For this purpose, a graphical user interface program which can be used for educational purpose has been developed. For the definite (entered transfer functions, the suitable P, PI and PID controller coefficients have calculated by both classical methods and genetic algorithms and many parameters and responses of the systems have been compared and presented numerically and graphically
Fuzzy adaptive PID control for six rotor eppo UAV
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Yongwei LI
2017-02-01
Full Text Available Six rotor eppo drones's load change itself in the job process will reduce the aircraft flight control performance and make the resistance to environmental disturbance being poor. In order to improve the six rotor eppo unmanned aerial vehicle (UAV control performance, the UAV in the process of spraying pesticide is analyzed and the model is constructed, then the eppo UAV time-varying dynamics mathematical model is deduced, and a fuzzy adaptive PID control algorithm is proposed. Fuzzy adaptive PID algorithm has good adaptability and the parameter setting is simple, which improves the system dynamic response and steady state performance, realizing the stability of the six rotor eppo UAV flight. With measured parameters of each sensor input in to the fuzzy adaptive PID algorithm, the corresponding control quality is obtained, and the stable operation of aircraft is realized. Through using Matlab to simulate the flight system and combining the practical experiments, it shows that the dynamic performance and stability of the system is improved effetively.
Pattern recognition and PID procedure with the ALICE-HMPID
Volpe, Giacomo
2014-01-01
The ALICE apparatus is dedicated to the study of pp, p–Pb and Pb–Pb collisions provided by LHC. ALICE has unique particle identification (PID) capabilities among the LHC experiments exploiting different PID techniques, i.e., energy loss, time-of-flight measurements, Cherenkov and transition radiation detection, calorimetry and topological ID. The ALICE-HMPID is devoted to the identification of charged hadrons. It consists of seven identical RICH counters, with liquid C6F14 as Cherenkov radiator (n ≈1.299 at λ ph=175 nm). Photons and charged particles detection is performed by a proportional chamber, coupled with a pad segmented CsI coated photo-cathode. In pp and p–Pb events HMPID provides 3 sigmas separation for pions and kaons up to View the MathML sourcepT=3GeV/c and for protons up to View the MathML sourcepT=5GeV/c. PID is performed by means of photon emission angle measurement, a challenging task in the high multiplicity environment of the most central Pb–Pb collisions. A dedicated algorithm h...
Development of Solar Tracking System Using Imc-Pid Controller
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Bamigboye O. Oladayo
2016-06-01
Full Text Available In the past, solar cells are hooked with fixed elevating angles, and it does not track the sun. Therefore the efficiency of the power generation is low. A solar panel receives the most sunlight when it is perpendicular to the sun’s rays, but the sunlight direction changes regularly with changing seasons and weather. There is therefore the need to track the solar panel to increase its efficiency. The stability and improved speed of response can only be achieved with appropriate controller to take care of external disturbances and design uncertainty associated with a conventional controller. The IMC controller would be used to allow good tracking ability and good load disturbance rejection Unconventional controller like fuzzy logic can be used to tune the PID controller andthe result compared with using a conventional controller like ZN. The internal model control based proportional integral derivative design procedure can be implemented in industrial processes using existing proportional integral derivative control equipment. Modeling of a dual axis solar tracker. An IMC-PID controller was developed for a dual axis solar tracker. The result of this work showed that the IMC-PID controller provided an efficient and commendable improvement in the relative stability, disturbance attenuation, set point tracking and an improved speed of response for the system
一种改进的模式识别自整定PID控制方法%Improved Self-tuning PID Control Based on Pattern Recognition
Institute of Scientific and Technical Information of China (English)
穆克; 苏成利
2012-01-01
To solve the shortcomings of traditional PID conlroller in dealing with disturbance rejection and robustness. A new self-tuning PID-based algorithm for pattern recognition is proposed. In the algorithm, the parameter tuning rules of the PID controller are innovated, and the specificformula for setting the rules is put forward. In order to achieve the water tank level control algorithm in the application of laboratory, using OPC technology to achieve the MATLAB software and data configuration software MCGS real-time interaction. Experimental results show that the given tuning rules in MATLAB simulation and tank level control applications take the effect of good tuning. The control performance of the proposed self-tuning PID control method is superior to that of traditional PID method.%针对常规PID控制器不能很好地兼顾抗干扰性与鲁棒性的缺点,提出一种新的基于模式识别自整定PID控制算法.该算法对参数整定规则进行了探索和创新,并给出具体的整定规则公式.为了实现算法在实验室水箱液位控制的应用,采用OPC技术实现了MATLAB软件与MCGS组态软件的数据实时交互.实验结果表明,该规则在MALAB仿真和水箱液位控制应用中取得到了很好的整定效果,控制性能优于常规PID控制.
Design of PID controller with incomplete derivation based on ant system algorithm
Institute of Scientific and Technical Information of China (English)
Guanzheng TAN; Qingdong ZENG; Wenbin LI
2004-01-01
A new and intelligent design method for PID controller with incomplete derivation is proposed based on the ant system algorithm (ASA).For a given control system with this kind of PID controller,a group of optimal PID controller parameters K*p,T*i, and T*d can be obtained by taking the overshoot,settling time,and steady-state error of the system's unit step response as the performance indexes and by use of our improved ant system algorithm.K*p,T*i, and T*d can be used in real-time control.This kind of controller is called the ASA-PID controller with incomplete derivation.To verify the performance of the ASA-PID controller,three different typical transfer functions were tested,and three existing typical tuning methods of PID controller parameters,including the Ziegler-Nichols method (ZN),the genetic algorithm (GA),and the simulated annealing (SA),were adopted for comparison.The simulation results showed that the ASA-PID controller can be used to control different objects and has better performance compared with the ZN-PID and GA-PID controllers,and comparable performance compared with the SA-PID controller.
Multivariate Birkhoff interpolation
Lorentz, Rudolph A
1992-01-01
The subject of this book is Lagrange, Hermite and Birkhoff (lacunary Hermite) interpolation by multivariate algebraic polynomials. It unifies and extends a new algorithmic approach to this subject which was introduced and developed by G.G. Lorentz and the author. One particularly interesting feature of this algorithmic approach is that it obviates the necessity of finding a formula for the Vandermonde determinant of a multivariate interpolation in order to determine its regularity (which formulas are practically unknown anyways) by determining the regularity through simple geometric manipulations in the Euclidean space. Although interpolation is a classical problem, it is surprising how little is known about its basic properties in the multivariate case. The book therefore starts by exploring its fundamental properties and its limitations. The main part of the book is devoted to a complete and detailed elaboration of the new technique. A chapter with an extensive selection of finite elements follows as well a...
Applied multivariate statistical analysis
Härdle, Wolfgang Karl
2015-01-01
Focusing on high-dimensional applications, this 4th edition presents the tools and concepts used in multivariate data analysis in a style that is also accessible for non-mathematicians and practitioners. It surveys the basic principles and emphasizes both exploratory and inferential statistics; a new chapter on Variable Selection (Lasso, SCAD and Elastic Net) has also been added. All chapters include practical exercises that highlight applications in different multivariate data analysis fields: in quantitative financial studies, where the joint dynamics of assets are observed; in medicine, where recorded observations of subjects in different locations form the basis for reliable diagnoses and medication; and in quantitative marketing, where consumers’ preferences are collected in order to construct models of consumer behavior. All of these examples involve high to ultra-high dimensions and represent a number of major fields in big data analysis. The fourth edition of this book on Applied Multivariate ...
Xu, Jingying; Ren, Xiuhai; Pathania, Anup Singh; Fernandez, G Esteban; Tran, Anthony; Zhang, Yifu; Moats, Rex A; Shackleford, Gregory M; Erdreich-Epstein, Anat
2017-04-11
Phosphotyrosine Interaction Domain containing 1 (PID1; NYGGF4) inhibits growth of medulloblastoma, glioblastoma and atypical teratoid rhabdoid tumor cell lines. PID1 tumor mRNA levels are highly correlated with longer survival in medulloblastoma and glioma patients, suggesting their tumors may have been more sensitive to therapy. We hypothesized that PID1 sensitizes brain tumors to therapy. We found that PID1 increased the apoptosis induced by cisplatin and etoposide in medulloblastoma and glioblastoma cell lines. PID1 siRNA diminished cisplatin-induced apoptosis, suggesting that PID1 is required for cisplatin-induced apoptosis. Etoposide and cisplatin increased NFκB promoter reporter activity and etoposide induced nuclear translocation of NFκB. Etoposide also increased PID1 promoter reporter activity, PID1 mRNA, and PID1 protein, which were diminished by NFκB inhibitors JSH-23 and Bay117082. However, while cisplatin increased PID1 mRNA, it decreased PID1 protein. This decrease in PID1 protein was mitigated by the proteasome inhibitor, bortezomib, suggesting that cisplatin induced proteasome dependent degradation of PID1. These data demonstrate for the first time that etoposide- and cisplatin-induced apoptosis in medulloblastoma and glioblastoma cell lines is mediated in part by PID1, involves NFκB, and may be regulated by proteasomal degradation. This suggests that PID1 may contribute to responsiveness to chemotherapy.
Multivariate bubbles and antibubbles
Fry, John
2014-08-01
In this paper we develop models for multivariate financial bubbles and antibubbles based on statistical physics. In particular, we extend a rich set of univariate models to higher dimensions. Changes in market regime can be explicitly shown to represent a phase transition from random to deterministic behaviour in prices. Moreover, our multivariate models are able to capture some of the contagious effects that occur during such episodes. We are able to show that declining lending quality helped fuel a bubble in the US stock market prior to 2008. Further, our approach offers interesting insights into the spatial development of UK house prices.
Multiobjective Optimization Design of a Fractional Order PID Controller for a Gun Control System
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Qiang Gao
2013-01-01
Full Text Available Motion control of gun barrels is an ongoing topic for the development of gun control equipments possessing excellent performances. In this paper, a typical fractional order PID control strategy is employed for the gun control system. To obtain optimal parameters of the controller, a multiobjective optimization scheme is developed from the loop-shaping perspective. To solve the specified nonlinear optimization problem, a novel Pareto optimal solution based multiobjective differential evolution algorithm is proposed. To enhance the convergent rate of the optimization process, an opposition based learning method is embedded in the chaotic population initialization process. To enhance the robustness of the algorithm for different problems, an adapting scheme of the mutation operation is further employed. With assistance of the evolutionary algorithm, the optimal solution for the specified problem is selected. The numerical simulation results show that the control system can rapidly follow the demand signal with high accuracy and high robustness, demonstrating the efficiency of the proposed controller parameter tuning method.
PID1 IS A NOVEL SENSITIZER OF BRAIN TUMOR CELLS TO CHEMOTHERAPY
Erdreich-Epstein, Anat; Xu, Jingying; Ren, Xiuhai
2014-01-01
BACKGROUND: PID1 is a phosphotyrosine binding domain-containing protein of unknown function in cancer. We recently provided the first report of PID1 in brain tumors (and in cancer). PID1 inhibits growth and proliferation and induces cell death, apoptosis and mitochondrial depolarization in glioblastoma, medulloblastoma and ATRT cell lines. PID1 siRNA had the opposite effect on mitochondrial depolarization. PID1 mRNA level was directly correlated with survival of patients with medulloblastoma or glioma: PID1 mRNA was lowest in tumor subgroups with the poorest prognosis and highest in the more favorable prognosis groups within each diagnosis. The mechanism by which PID1 affects these tumors is currently unknown, and is the focus of studies in our laboratory. METHODS: Experiments were conducted in tissue culture in primary and established cell lines using established methods to assess mRNA, proliferation and signal transduction. RESULTS: Since lower PID1 mRNA was associated with poorer outcome in medulloblastoma and gliomas and higher PID1 was associated with improved outcome, we hypothesized that PID1 level may affect responsiveness of these brain tumors to therapy: higher responsiveness in tumors with high PID1 and resistance when it is low. Indeed, while both cisplatin (10 µg/ml) or transient PID1 overexpression increased apoptosis of glioma and medulloblastoma cell lines (indicated by increased AnnexinV, caspase-3 cleavage and mitochondrial depolarization), combining cisplatin with PID1 caused a markedly higher effect than each alone. Moreover, knockdown of PID1 by siRNA inhibited the cisplatin-induced mitochondrial membrane depolarization and apoptosis (AnnexinV and caspase-3 cleavage), suggesting that PID1 may be required for cisplatin-induced apoptosis. This supports our hypothesis that PID1 may sensitize brain tumor cells to chemotherapy. Intriguingly, PID1 mRNA increased in response to cisplatin (5 µg/ml) as well as to etoposide (5 µg/ml) and vincristine
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Manikandan Ramasamy
2017-07-01
Full Text Available Automation has been growing in recent years for the manufacturing industries to increase productivity. Multiple robotic arms are used to handle materials for lifting in flexible directions. The vertical rotation of a 360 degree single arm is considered in this research on a position servo drive with brushless DC motor. The load torque of an arm varies depending upon the angular displacement due to gravity, so it requires four-quadrant operation of the drive with a robust feedback controller. This paper deals with the design and performance comparison of a conventional PID feedback controller with a fuzzy-based PID controller and suggests the most suitable controller. The design was implemented in real time through the dSPACE DS1104 controller environment to verify the dynamic behaviors of the arm.
DEFF Research Database (Denmark)
Hansen, Michael Adsetts Edberg
Interest in statistical methodology is increasing so rapidly in the astronomical community that accessible introductory material in this area is long overdue. This book fills the gap by providing a presentation of the most useful techniques in multivariate statistics. A wide-ranging annotated set...
DEFF Research Database (Denmark)
Hansen, Michael Adsetts Edberg
Interest in statistical methodology is increasing so rapidly in the astronomical community that accessible introductory material in this area is long overdue. This book fills the gap by providing a presentation of the most useful techniques in multivariate statistics. A wide-ranging annotated set...
A MULTIVARIATE WEIBULL DISTRIBUTION
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Cheng Lee
2010-07-01
Full Text Available A multivariate survival function of Weibull Distribution is developed by expanding the theorem by Lu and Bhattacharyya. From the survival function, the probability density function, the cumulative probability function, the determinant of the Jacobian Matrix, and the general moment are derived.
A Practical Application of IMC-PID Controller in Unmanned Vehicle
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Qin Gang
2013-06-01
Full Text Available In allusion to unmanned vehicle steering control of the brushless DC motor control system, traditional PID controller parameter adjustment complex, weak ability to adapt to the environment and other issues, on the basis of the analysis of internal model control and classical PID control internal corresponding relationship, comprehensive its advantages, The design uses a brushless DC motor in the steering control system for unmanned vehicles based on the internal model PID controller ( IMC-PID for speed. Based on the build object theoretical model, online simulation controller show that, for the design objects, based on the internal model PID controller whether the system step response or disturbance tracking control effect can reach the classic PID control requirements, also reduces the complexity and randomness of the design parameters.
Design and Simulation of PID parameters self-tuning based on DC speed regulating system
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Feng Wei Jie
2016-01-01
Full Text Available The DC speed regulating system has many difficult issues such as system parameters and PID control parameters are difficult to determine. On the basis of model for a single closed-loop DC speed regulating system, this paper puts forward a method of PID parameters self-tuning based on the step response detection and reduced order equivalent. First, detect system step response and get response parameters. Then equal it to a second order system model, and achieve optimal PID control parameters based on optimal second order system to realize of PID parameters self-tuning. The PID parameters self-tuning process of DC speed regulating system is simulated with the help of MATLAB/Simulink. The simulation results show that the method is simple and effective. The system can obtain good dynamic and static performance when the PID parameters are applied to DC speed regulating system.
CAS algorithm-based optimum design of PID controller in AVR system
Energy Technology Data Exchange (ETDEWEB)
Zhu Hui [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); Key Laboratory of Network and Information Attack and Defence Technology of Ministry of Education, Beijing University of Posts and Telecommunications, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing 100876 (China)], E-mail: zhuhui05608@hotmail.com; Li Lixiang; Zhao Ying; Guo Yu; Yang Yixian [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); Key Laboratory of Network and Information Attack and Defence Technology of Ministry of Education, Beijing University of Posts and Telecommunications, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing 100876 (China)
2009-10-30
This paper presents a novel design method for determining the optimal PID controller parameters of an automatic voltage regulator (AVR) system using the chaotic ant swarm (CAS) algorithm. In the tuning process of parameters, the CAS algorithm is iterated to give the optimal parameters of the PID controller based on the fitness theory, where the position vector of each ant in the CAS algorithm corresponds to the parameter vector of the PID controller. The proposed CAS-PID controllers can ensure better control system performance with respect to the reference input in comparison with GA-PID controllers. Numerical simulations are provided to verify the effectiveness and feasibility of PID controller based on CAS algorithm.
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Antonio Yarza
2011-09-01
Full Text Available An unsolved ancient problem in position control of robot manipulators is to find a stability analysis that proves global asymptotic stability of the classical PID control in closed loop with robot manipulators. The practical evidence suggests that in fact the classical PID in industrial robots is a global regulator. The main goal of the present paper is theoretically to show why in the practice such a fact is achieved. We show that considering the natural saturations of every control stage in practical robots, the classical PID becomes a type of saturated nonlinear PID controller. In this work such a nonlinear PID controller with bounded torques for robot manipulators is proposed. This controller, unlike other saturated nonlinear PID controllers previously proposed, uses a single saturation for the three terms of the controller. Global asymptotical stability is proved via Lyapunov stability theory. Experimental results are presented in order to observe the performance of the proposed controller.
Advanced Fireworks Algorithm and Its Application Research in PID Parameters Tuning
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Jun-jie Xue
2016-01-01
Full Text Available Proportional-Integral-Derivative (PID controller is one of the most widely used controllers for its property of simplicity and practicability. In order to design high-quality performances PID controllers, an Advanced Fireworks (AFW algorithm based on self-adaption principle and bimodal Gaussian function is proposed, which is built to optimize the PID controller by parameters tuning. Firstly, a compound index of optimization performance is formulated, and then the extremal optimization method of PID control system is proposed. Secondly, a PID parameters tuning model combined with AFW is built. At last, 5 typical transfer functions are simulated to obtain optimal parameters by AFW and contrast tuning method, such as Ziegler-Nichols method, Enhanced Fireworks (EFW algorithm, and Particle Swarm Optimization (PSO. Simulation results show that AFW are effective and are easily implemented methods to solve PID control problems of different transfer functions.
Comparison of PID and Fuzzy Controller for Position Control of AR.Drone
Prayitno, A.; Indrawati, V.; Trusulaw, I. I.
2017-04-01
This paper describes the implementation of the PID Controller to control the position of the AR.Drone in the x-y-z. This position control scheme uses three PID controllers to maintain the position of x, y and z using the signal control pitch, roll and vertical rate. PID Controller implemented on AR.Drone 2.0 and then tested in an indoor space. The performance of the controller will be compared with Fuzzy Logic Controller schemes that have been implemented previously. The results show that the PID Controller generate a response with rise time less than 3 seconds at the x and y position with around 25% overshoot. The result for z position give better result without overshoot. The comparison between fuzzy logic and PID Controller indicates that the results of the PID controller is better although there is overshoot.
Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms
Institute of Scientific and Technical Information of China (English)
杨彪; 梁贵安; 彭金辉; 郭胜惠; 李玮; 张世敏; 李英伟; 白松
2013-01-01
The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design.
Tuning of PID Controller for A Linear Brushless DC Motor using Swarm Intelligence Technique
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Pooja Sharma,
2014-05-01
Full Text Available An Optimal Design of PID Controller is proposed in this paper. The Methodology of PSO Algorithm is utilized to search the optimal parameters of Proportional Integral Derivative (PID Controller for BLDC Motor. PSO is an Evolutionary Optimization Technique. A Linear Brushless DC Motors are known for higher efficiency and lower maintenance. The Brushless DC Motor is modeled in Simulink & tuning of PID controller using PSO is implemented in MATLAB. This Method was more efficient for Step Response Characteristics.
Structure Analysis and Function Evaluation of a Kind of Fuzzy PID Controllers
Institute of Scientific and Technical Information of China (English)
DUXinyu; ZHANGNaiyao; YUNa
2004-01-01
In this paper, a kind of fuzzy PID (Proportional integral and derivate) controllers is discussed, which has 3 input variables (error, difference of error, sum of error) and one output variable; triangular fully-overlapped symmetric membership function for input variables; singleton equally-spaced membership function for the output variable; linear control rules; Sum-Product inference method; and Center of area (COA) defuzzification algorithm. The paper consists of three main parts. In the first part, the structure properties of fuzzy PID controllers are studied. The explicit expression of this kind of fuzzy PID controllers is derived. It is proved that the analytical structure of fuzzy PID controllers is the sum of a global three-dimensional multi-level relay and a local nonlinear controller. When the number of fuzzy sets tends to infinity, the local nonlinear controller will disappear, and the degree of nonlinearity of the fuzzy PID controller becomes zero. In the second part, the function properties of fuzzy PID controllers are studied. It is revealed that the fuzzy PID controller is a variable gain nonlinear PID controller; so linear PID controllers can be regarded as a special example of fuzzy PID controllers. Moreover, they are equivalent to the sum of three fuzzy controllers with one-to-one mapping; so they do not suffer from some weaknesses such as composed-action, input coupling, etc. Based on these theoretical results, a systematic design approach of fuzzy PID control systems is proposed and demonstrated by 2 simulation examples in the third part of this paper. It is shown that the proposed fuzzy PID controller not only has good structure and function characteristics, but also can be very simply and quickly designed; therefore, it is very suitable for a wide range of applications.
The design for the fuzzy PID control of the intelligent following vehicle with gas floating
Institute of Scientific and Technical Information of China (English)
He Yi; Song Xiaodong; Chen Ming
2012-01-01
The intelligent following vehicle with gas floating has the characteristics of complicated structure and large quality. In this paper ,the author first establish the mathematical mode of the motion system land and then design a controller using the fuzzy PID control method which could realize auto-tuning PID parameters. By the MATLAB simulation analysis, the results show that fuzzy self-tuning PID control can enhance the response speed of system and has a better adaptability.
Institute of Scientific and Technical Information of China (English)
吴剑威; 孔慧芳; 唐立新
2013-01-01
The temperature control system of polymerization reactor has characteristics of time-varying,nonlinearity and lag,and it is difficult to create the mathematical model and get the parameters precisely,which seriously affects the rapidity and robustness of temperature control system.An intelligent fuzzy adaptive PID (IFA-PID) control algorithm is proposed in order to solve the problems.The fuzzy control is used when the error is large and the fuzzy adaptive PID (FA-PID) control with independent differentiation is used when the error is small.Furthermore,a smooth handoff is achieved by switching function between the two control modes,thus the complement of the advantages andorganic combination has been realized.Then the simulation model is created in Simulink toolbox of Matlab for simulation comparison experiment of traditional PID control、FA-PID control and IFA-PID control under model matching and model mismatch.Simulation results show IFA-PID is better than the other two algorithms in overshoot,settling time and other performance index,in addition,it has better adaptability and stability,and it can improve the quality characteristics and control precision of system.The presented algorithm can effectively overcome the model mismatch and parameters variation,which is very suitable for the control of nonlinear system with time-varying delay.%化学反应釜温度控制系统具有时变性、非线性、滞后性等特点,数学模型和参数难以精确得到,严重影响了温度控制的快速性和鲁棒性.为解决这些问题,设计了一种智能模糊自适应PID(Intelligent Fuzzy Adaptive PID,IFA-PID)控制算法,当误差较大时采用模糊控制,误差较小时采用微分独立模糊自适应PID(Fuzzy Adaptive PID,FA-PID)控制,通过切换函数实现两种控制方式的平滑切换,实现了2种控制方法的有机结合和优势互补.利用MATLAB的Simulink仿真工具箱建立模型,并做了传统PID、FA-PID以及IFA-PID在
Fuzzy PID control algorithm based on PSO and application in BLDC motor
Lin, Sen; Wang, Guanglong
2017-06-01
A fuzzy PID control algorithm is studied based on improved particle swarm optimization (PSO) to perform Brushless DC (BLDC) motor control which has high accuracy, good anti-jamming capability and steady state accuracy compared with traditional PID control. The mathematical and simulation model is established for BLDC motor by simulink software, and the speed loop of the fuzzy PID controller is designed. The simulation results show that the fuzzy PID control algorithm based on PSO has higher stability, high control precision and faster dynamic response speed.
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Li Jing
2016-01-01
Full Text Available For the control of the liquid level of liquid ammonia in thermal power plant’s ammonia vaporization room, traditional PID controller parameter tuning is difficult to adapt to complex control systems, the setting of the traditional PID controller parameters is difficult to adapt to the complex control system. For the disadvantage of bad parameter setting, poor performance and so on the fuzzy adaptive PID control is proposed. Fuzzy adaptive PID control combines the advantages of traditional PID technology and fuzzy control. By using the fuzzy controller to intelligent control the object, the performance of the PID controller is further improved, and the control precision of the system is improved[1]. The simulation results show that the fuzzy adaptive PID controller not only has the advantages of high accuracy of PID controller, but also has the characteristics of fast and strong adaptability of fuzzy controller. It realizes the optimization of PID parameters which are in the optimal state, and the maximum increase production efficiency, so that are more suitable for nonlinear dynamic system.
GENETIC ALGORITHM BASED PARAMETER TUNING OF PID CONTROLLER FOR COMPOSITION CONTROL SYSTEM
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Bhawna Tandon
2011-08-01
Full Text Available A Composition control system is discussed in this paper in which the PID controller is tuned using Genetic Algorithm & Ziegler-Nichols Tuning Criteria. Tuning methods for PID controllers are very importantfor the process industries. Traditional methods such as Ziegler-Nichols method often do not provide adequate tuning. Genetic Algorithm (GA as an intelligent approach has also been widely used to tune the parameters of PID. Genetic algorithms are used to create an objective function that can evaluate the optimum PID gains based on the controlled systems overall error.
Simple PID parameter tuning method based on outputs of the closed loop system
Han, Jianda; Zhu, Zhiqiang; Jiang, Ziya; He, Yuqing
2016-05-01
Most of the existing PID parameters tuning methods are only effective with pre-known accurate system models, which often require some strict identification experiments and thus infeasible for many complicated systems. Actually, in most practical engineering applications, it is desirable for the PID tuning scheme to be directly based on the input-output response of the closed-loop system. Thus, a new parameter tuning scheme for PID controllers without explicit mathematical model is developed in this paper. The paper begins with a new frequency domain properties analysis of the PID controller. After that, the definition of characteristic frequency for the PID controller is given in order to study the mathematical relationship between the PID parameters and the open-loop frequency properties of the controlled system. Then, the concepts of M-field and θ-field are introduced, which are then used to explain how the PID control parameters influence the closed-loop frequency-magnitude property and its time responses. Subsequently, the new PID parameter tuning scheme, i.e., a group of tuning rules, is proposed based on the preceding analysis. Finally, both simulations and experiments are conducted, and the results verify the feasibility and validity of the proposed methods. This research proposes a PID parameter tuning method based on outputs of the closed loop system.
Differential Evolution-Based PID Control of Nonlinear Full-Car Electrohydraulic Suspensions
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Jimoh O. Pedro
2013-01-01
Full Text Available This paper presents a differential-evolution- (DE- optimized, independent multiloop proportional-integral-derivative (PID controller design for full-car nonlinear, electrohydraulic suspension systems. The multiloop PID control stabilises the actuator via force feedback and also improves the system performance. Controller gains are computed using manual tuning and through DE optimization to minimise a performance index, which addresses suspension travel, road holding, vehicle handling, ride comfort, and power consumption constraints. Simulation results showed superior performance of the DE-optimized PID-controlled active vehicle suspension system (AVSS over the manually tuned PID-controlled AVSS and the passive vehicle suspension system (PVSS.
Rudder-roll stabilization using fgs-pid controller for sigma-e warship
Santoso, M. Y.; Munadhif, I.; Wahidin, A.; Ruddianto; Fathulloh; Soelistijono, R. T.
2017-06-01
The aim of rudder-roll stabilization (RSS) is controlling ship heading and reducing roll motion simultaneously using one actuator, rudder. In this paper, RSS using FGS-PID for SIGMA-e warship was performed, both in normal and disturbed sea conditions. The fuzzy system for determining PID controller are constructed from SIGMA-e linear mathematical model. The wave disturbances are generated based on the WMO. The results show that FGS-PID has superior performance compared to conventional PID controller in heading control and roll damping. It means that the proposed control method can encounter the environmental changes.
DEFF Research Database (Denmark)
Gorm Hansen, Birgitte
The concepts of “socially robust knowledge” and “mode 2 knowledge production” (Nowotny 2003, Gibbons et al. 1994) have migrated from STS into research policy practices. Both STS-scholars and policy makers have been known to propomote the idea that the way forward for today’s scientist is to jump...... from the ivory tower and learn how to create high-flying synergies with citizens, corporations and governments. In STS as well as in Danish research policy it has thus been argued that scientists will gain more support and enjoy greater success in their work by “externalizing” their research...... and adapting their interests to the needs of outside actors. However, when studying the concrete strategies of such successful scientists, matters seem a bit more complicated. Based on interviews with a plant biologist working in GMO the paper uses the biological concepts of field participants...
DEFF Research Database (Denmark)
Aanæs, Henrik; Fisker, Rune; Åström, Kalle;
2002-01-01
Factorization algorithms for recovering structure and motion from an image stream have many advantages, but they usually require a set of well-tracked features. Such a set is in generally not available in practical applications. There is thus a need for making factorization algorithms deal...... effectively with errors in the tracked features. We propose a new and computationally efficient algorithm for applying an arbitrary error function in the factorization scheme. This algorithm enables the use of robust statistical techniques and arbitrary noise models for the individual features....... These techniques and models enable the factorization scheme to deal effectively with mismatched features, missing features, and noise on the individual features. The proposed approach further includes a new method for Euclidean reconstruction that significantly improves convergence of the factorization algorithms...
Skopina, Maria; Protasov, Vladimir
2016-01-01
This book presents a systematic study of multivariate wavelet frames with matrix dilation, in particular, orthogonal and bi-orthogonal bases, which are a special case of frames. Further, it provides algorithmic methods for the construction of dual and tight wavelet frames with a desirable approximation order, namely compactly supported wavelet frames, which are commonly required by engineers. It particularly focuses on methods of constructing them. Wavelet bases and frames are actively used in numerous applications such as audio and graphic signal processing, compression and transmission of information. They are especially useful in image recovery from incomplete observed data due to the redundancy of frame systems. The construction of multivariate wavelet frames, especially bases, with desirable properties remains a challenging problem as although a general scheme of construction is well known, its practical implementation in the multidimensional setting is difficult. Another important feature of wavelet is ...
Multivariate calculus and geometry
Dineen, Seán
2014-01-01
Multivariate calculus can be understood best by combining geometric insight, intuitive arguments, detailed explanations and mathematical reasoning. This textbook has successfully followed this programme. It additionally provides a solid description of the basic concepts, via familiar examples, which are then tested in technically demanding situations. In this new edition the introductory chapter and two of the chapters on the geometry of surfaces have been revised. Some exercises have been replaced and others provided with expanded solutions. Familiarity with partial derivatives and a course in linear algebra are essential prerequisites for readers of this book. Multivariate Calculus and Geometry is aimed primarily at higher level undergraduates in the mathematical sciences. The inclusion of many practical examples involving problems of several variables will appeal to mathematics, science and engineering students.
Multivariate Quantitative Chemical Analysis
Kinchen, David G.; Capezza, Mary
1995-01-01
Technique of multivariate quantitative chemical analysis devised for use in determining relative proportions of two components mixed and sprayed together onto object to form thermally insulating foam. Potentially adaptable to other materials, especially in process-monitoring applications in which necessary to know and control critical properties of products via quantitative chemical analyses of products. In addition to chemical composition, also used to determine such physical properties as densities and strengths.
Multivariate $\\alpha$-molecules
Flinth, Axel; Schäfer, Martin
2015-01-01
The suboptimal performance of wavelets with regard to the approximation of multivariate data gave rise to new representation systems, specifically designed for data with anisotropic features. Some prominent examples of these are given by ridgelets, curvelets, and shearlets, to name a few. The great variety of such so-called directional systems motivated the search for a common framework, which unites many under one roof and enables a simultaneous analysis, for example with respect to approxim...
Transient multivariable sensor evaluation
Energy Technology Data Exchange (ETDEWEB)
Vilim, Richard B.; Heifetz, Alexander
2017-02-21
A method and system for performing transient multivariable sensor evaluation. The method and system includes a computer system for identifying a model form, providing training measurement data, generating a basis vector, monitoring system data from sensor, loading the system data in a non-transient memory, performing an estimation to provide desired data and comparing the system data to the desired data and outputting an alarm for a defective sensor.
Transient multivariable sensor evaluation
Vilim, Richard B.; Heifetz, Alexander
2017-02-21
A method and system for performing transient multivariable sensor evaluation. The method and system includes a computer system for identifying a model form, providing training measurement data, generating a basis vector, monitoring system data from sensor, loading the system data in a non-transient memory, performing an estimation to provide desired data and comparing the system data to the desired data and outputting an alarm for a defective sensor.
Multivariate Quantitative Chemical Analysis
Kinchen, David G.; Capezza, Mary
1995-01-01
Technique of multivariate quantitative chemical analysis devised for use in determining relative proportions of two components mixed and sprayed together onto object to form thermally insulating foam. Potentially adaptable to other materials, especially in process-monitoring applications in which necessary to know and control critical properties of products via quantitative chemical analyses of products. In addition to chemical composition, also used to determine such physical properties as densities and strengths.
Search for B+/- --> [K-/+ pi+/-]_D K+/- and upper limit on the b --> u amplitude in B+/- --> D K+/-
Aubert, B; Boutigny, D; Couderc, F; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Le Clerc, C; Lynch, G; Merchant, A M; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Çuhadar-Dönszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Gary, J W; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Zhang, L; Chen, A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q L; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Khan, A; Lavin, D; Muheim, F; Playfer, S; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, Erwin; Gamet, R; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Del Gamba, V; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Elsen, E E; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, Patricia R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Di Lodovico, F; Mihályi, A; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu, S L; Yu, Z; Neal, H
2004-01-01
We search for B+/- --> [K^-/+ pi+/-]_D K+/- decays, where [K-/+ pi+/-]_D indicates that the K-/+ pi+/- pair originates from the decay of a D0 or D0bar. Results are based on 120 million Upsilon(4S) --> B Bbar decays collected with the BaBar detector at SLAC. We set an upper limit on the ratio R_Kpi = {Gamma(B+ --> [K- pi+]_D K+) + Gamma(B- --> [K+ pi-]_D K-)}/ {Gamma(B+ --> [K+ pi-]_D K+) + Gamma(B- --> [K- pi+]_D K-)} D0bar K-)/A(B- --> D0 K-)| D K will be difficult.
Hu, Wuhua; Xiao, Gaoxi; Li, Xiumin
2011-04-01
In this paper, an analytical method is proposed for proportional-integral/proportional-derivative/proportional-integral-derivative (PI/PD/PID) controller tuning with specified gain and phase margins (GPMs) for integral plus time delay (IPTD) processes. Explicit formulas are also obtained for estimating the GPMs resulting from given PI/PD/PID controllers. The proposed method indicates a general form of the PID parameters and unifies a large number of existing rules as PI/PD/PID controller tuning with various GPM specifications. The GPMs realized by existing PID tuning rules are computed and documented as a reference for control engineers to tune the PID controllers.
Stable visual PID control of a planar parallel robot
Garrido Moctezuma, Ruben; Soria López, Alberto; Trujano Cabrera, Miguel
2008-11-01
In this paper, we study an image-based PID control of a redundant planar parallel robot using a fixed camera configuration. The control objective is to move the robot end effector to the desired image reference position. The control law has a PD term plus an integral term with a nonlinear function of the position error. The proportional and integral actions use image loop information whereas the derivative action adds task space damping using joint level measurements. The Lyapunov method and the LaSalle invariance principle allow assessing asymptotic closed loop stability. Experiments show the feasibility of the proposed approach.
A method for closed loop automatic tuning of PID controllers
Directory of Open Access Journals (Sweden)
Tor S. Schei
1992-07-01
Full Text Available A simple method for the automatic tuning of PID controllers in closed loop is proposed. A limit cycle is generated through a nonlinear feedback path from the process output to the controller reference signal. The frequency of this oscillation is above the crossover frequency and below the critical frequency of the loop transfer function. The amplitude and frequency of the oscillation are estimated and the control parameters are adjusted iteratively such that the closed loop transfer function from the controller reference to the process output attains a specified amplitude at the oscillation frequency.
Retour sur l’épidémiologie populaire
Brown, Phil
2013-01-01
Dans un article de 1987, j’ai forgé l’expression d’« épidémiologie populaire » pour décrire les pratiques de signalement, d’analyse scientifique et de mobilisation politique des populations vivant sur des sites contaminés par des déchets toxiques (Brown, 1987). Depuis lors, j’ai développé ce concept dans plusieurs articles (Brown, 1992 ; Brown & Masterson-Allen, 1994 ; Brown & Ferguson, 1995), dans un livre (Brown & Mikkelsen, 1990), et de nombreux chercheurs l’ont jugé suffisamment utile pou...
The development of Gallstone solvent temperature adaptive PID control system
Institute of Scientific and Technical Information of China (English)
MA; BING; QIAO; BO; YAN
2012-01-01
The paper expatiated the work principle,general project,and the control part of the corresponding program of the temperature system in the gallstone dissolving instrument.Gallstone dissolving instrument adopts automatic control solvent cycle of direct solution stone treatment,replacing the traditional external shock wave rock row stone and gallblad-der surgery method.PID control system to realize the gall stone solvent temperature intelligent control,the basic principle of work is as solvent temperature below the set temperature,the relay control heater to solvent to be heated,conversely,no heating,achieve better able to dissolve the the rapeutic effect of gallstones.
Directory of Open Access Journals (Sweden)
Mohammed Shoeb Mohiuddin
2014-09-01
Full Text Available It is often difficult to develop an accurate mathematical model of DC motor due to unknown load variation, unknown and unavoidable parameter variations or nonlinearities due to saturation temperature variations and system disturbances. Fuzzy logic application can handle such nonlinearities so that the controller design is fundamentally robust which is not possible in conventional controllers. The knowledge base of a fuzzy logic controller (FLC encapsulates expert knowledge and consists of the Data base (membership functions and Rule-Base of the controller. Optimization of both these knowledge base components is critical to the performance of the controller and has traditionally been achieved through a process of trial and error. Such an approach is convenient for FLCs having low numbers of input variables however for greater numbers of inputs, more formal methods of knowledge base optimization are required. In this work, we study the challenging task of controlling the speed of DC motor. The feasibility of such controller design is evaluated by simulation in the MATLAB/Simulink environment. In this study Conventional Proportional Integral Derivative controller, Fuzzy logic controller using a chopper circuit and Fuzzy tuned PID controller are analyzed and compared. Simulation software like MATLAB with Simulink has been used for modeling and simulation purpose. The performance comparison of conventional controller with Fuzzy logic controller using chopper circuit and Fuzzy tuned PID controller has been done in terms of several performance measures Such as Settling time, Rise time and Overshoot.
Retraction: Pid1 Induces Insulin Resistance in Both Human and Mouse Skeletal Muscle during Obesity
Bonala, Sabeera; McFarlane, Craig; Ang, Jackie; Lim, Radiance; Lee, Marcus; Chua, Hillary; Lokireddy, Sudarsanareddy; Sreekanth, Patnam; Shing Leow, Melvin Khee; Meng, Khoo Chin; Shyong, TAI E; Lee, Yung Seng; Gluckman, Peter D.; Sharma, Mridula
2013-01-01
Obesity is associated with insulin resistance and abnormal peripheral tissue glucose uptake. However, the mechanisms that interfere with insulin signaling and glucose uptake in human skeletal muscle during obesity are not fully characterized. Using microarray, we have identified that the expression of Pid1 gene, which encodes for a protein that contains a phosphotyrosine-interacting domain, is increased in myoblasts established from overweight insulin-resistant individuals. Molecular analysis further validated that both Pid1 mRNA and protein levels are increased in cell culture models of insulin resistance. Consistent with these results, overexpression of phosphotyrosine interaction domain-containing protein 1 (PID1) in human myoblasts resulted in reduced insulin signaling and glucose uptake, whereas knockdown of PID1 enhanced glucose uptake and insulin signaling in human myoblasts and improved the insulin sensitivity following palmitate-, TNF-α-, or myostatin-induced insulin resistance in human myoblasts. Furthermore, the number of mitochondria in myoblasts that ectopically express PID1 was significantly reduced. In addition to overweight humans, we find that Pid1 levels are also increased in all 3 peripheral tissues (liver, skeletal muscle, and adipose tissue) in mouse models of diet-induced obesity and insulin resistance. An in silico search for regulators of Pid1 expression revealed the presence of nuclear factor-κB (NF-κB) binding sites in the Pid1 promoter. Luciferase reporter assays and chromatin immunoprecipitation studies confirmed that NF-κB is sufficient to transcriptionally up-regulate the Pid1 promoter. Furthermore, we find that myostatin up-regulates Pid1 expression via an NF-κB signaling mechanism. Collectively these results indicate that Pid1 is a potent intracellular inhibitor of insulin signaling pathway during obesity in humans and mice. PMID:23927930
Pid1 induces insulin resistance in both human and mouse skeletal muscle during obesity.
Bonala, Sabeera; McFarlane, Craig; Ang, Jackie; Lim, Radiance; Lee, Marcus; Chua, Hillary; Lokireddy, Sudarsanareddy; Sreekanth, Patnam; Leow, Melvin Khee Shing; Meng, Khoo Chin; Shyong, Tai E; Lee, Yung Seng; Gluckman, Peter D; Sharma, Mridula; Kambadur, Ravi
2013-09-01
Obesity is associated with insulin resistance and abnormal peripheral tissue glucose uptake. However, the mechanisms that interfere with insulin signaling and glucose uptake in human skeletal muscle during obesity are not fully characterized. Using microarray, we have identified that the expression of Pid1 gene, which encodes for a protein that contains a phosphotyrosine-interacting domain, is increased in myoblasts established from overweight insulin-resistant individuals. Molecular analysis further validated that both Pid1 mRNA and protein levels are increased in cell culture models of insulin resistance. Consistent with these results, overexpression of phosphotyrosine interaction domain-containing protein 1 (PID1) in human myoblasts resulted in reduced insulin signaling and glucose uptake, whereas knockdown of PID1 enhanced glucose uptake and insulin signaling in human myoblasts and improved the insulin sensitivity following palmitate-, TNF-α-, or myostatin-induced insulin resistance in human myoblasts. Furthermore, the number of mitochondria in myoblasts that ectopically express PID1 was significantly reduced. In addition to overweight humans, we find that Pid1 levels are also increased in all 3 peripheral tissues (liver, skeletal muscle, and adipose tissue) in mouse models of diet-induced obesity and insulin resistance. An in silico search for regulators of Pid1 expression revealed the presence of nuclear factor-κB (NF-κB) binding sites in the Pid1 promoter. Luciferase reporter assays and chromatin immunoprecipitation studies confirmed that NF-κB is sufficient to transcriptionally up-regulate the Pid1 promoter. Furthermore, we find that myostatin up-regulates Pid1 expression via an NF-κB signaling mechanism. Collectively these results indicate that Pid1 is a potent intracellular inhibitor of insulin signaling pathway during obesity in humans and mice.
Modeling a multivariable reactor and on-line model predictive control.
Yu, D W; Yu, D L
2005-10-01
A nonlinear first principle model is developed for a laboratory-scaled multivariable chemical reactor rig in this paper and the on-line model predictive control (MPC) is implemented to the rig. The reactor has three variables-temperature, pH, and dissolved oxygen with nonlinear dynamics-and is therefore used as a pilot system for the biochemical industry. A nonlinear discrete-time model is derived for each of the three output variables and their model parameters are estimated from the real data using an adaptive optimization method. The developed model is used in a nonlinear MPC scheme. An accurate multistep-ahead prediction is obtained for MPC, where the extended Kalman filter is used to estimate system unknown states. The on-line control is implemented and a satisfactory tracking performance is achieved. The MPC is compared with three decentralized PID controllers and the advantage of the nonlinear MPC over the PID is clearly shown.
Multivariate Term Structure Models with Level and Heteroskedasticity Effects
DEFF Research Database (Denmark)
Christiansen, Charlotte
2005-01-01
The paper introduces and estimates a multivariate level-GARCH model for the long rate and the term-structure spread where the conditional volatility is proportional to the ãth power of the variable itself (level effects) and the conditional covariance matrix evolves according to a multivariate GA...... and the level model. GARCH effects are more important than level effects. The results are robust to the maturity of the interest rates. Udgivelsesdato: MAY...
基于模糊自整定 PID 的永磁同步电机矢量控制%PMSM Vector ControI Based on Fuzzy SeIf-tuning PID
Institute of Scientific and Technical Information of China (English)
付光杰; 林雨晴; 崔海龙
2015-01-01
为克服传统的 PID 矢量控制系统存在响应速度慢及抗干扰能力差等缺点，提出基于模糊自整定 PID 的永磁同步电机矢量控制系统，并通过 Matlab 对传统 PID 和模糊自整定 PID 的控制效果进行对比，充分验证了该控制方法的可靠性和有效性。%To overcome disadvantages of traditional PID,a self-tuning PID control -based vector control sys-tem for permanent magnet synchronous motors (PMSM)was proposed,including comparing traditional PID with self-tuning PID control in MATLAB simulation.Simulation result verifies both feasibility and validity of this control method.
Gene therapy for PIDs: progress, pitfalls and prospects.
Mukherjee, Sayandip; Thrasher, Adrian J
2013-08-10
Substantial progress has been made in the past decade in treating several primary immunodeficiency disorders (PIDs) with gene therapy. Current approaches are based on ex-vivo transfer of therapeutic transgene via viral vectors to patient-derived autologous hematopoietic stem cells (HSCs) followed by transplantation back to the patient with or without conditioning. The overall outcome from all the clinical trials targeting different PIDs has been extremely encouraging but not without caveats. Malignant outcomes from insertional mutagenesis have featured prominently in the adverse events associated with these trials and have warranted intense pre-clinical investigation into defining the tendencies of different viral vectors for genomic integration. Coupled with issues pertaining to transgene expression, the therapeutic landscape has undergone a paradigm shift in determining safety, stability and efficacy of gene therapy approaches. In this review, we aim to summarize the progress made in the gene therapy trials targeting ADA-SCID, SCID-X1, CGD and WAS, review the pitfalls, and outline the recent advancements which are expected to further enhance favourable risk benefit ratios for gene therapeutic approaches in the future.
Digital implementation of fractional order PID controller and its application
Institute of Scientific and Technical Information of China (English)
Wang Zhenbin; Wang Zhenlei; Cao Guangyi; Zhu Xinjian
2005-01-01
A new discretization scheme is proposed for the design of a fractional order PID controller. In the design of a fractional order controller the interest is mainly focused on the s-domain, but there exists a difficult problem in the s-domain that needs to be solved, i.e. how to calculate fractional derivatives and integrals efficiently and quickly. Our scheme adopts the time domain that is well suited for Z-transform analysis and digital implementation. The main idea of the scheme is based on the definition of Grunwald-Letnicov fractional calculus. In this case some limited terms of the definition are taken so that it is much easier and faster to calculate fractional derivatives and integrals in the time domain or zdomain without loss much of the precision. Its effectiveness is illustrated by discretization of half-order fractional differential and integral operators compared with that of the analytical scheme. An example of designing fractional order digital controllers is included for illustration, in which different fractional order PID controllers are designed for the control of a nonlinear dynamic system containing one of the four different kinds of nonlinear blocks: saturation, deadzone, hysteresis, and relay.
Hybrid intelligent PID control design for PEMFC anode system
Institute of Scientific and Technical Information of China (English)
Rui-min WANG; Ying-ying ZHANG; Guang-yi CAO
2008-01-01
Control design is important for proton exchange membrane fuel cell (PEMFC) generator. This work researched the anode system of a 60-kW PEMFC generator. Both anode pressure and humidity must he maintained at ideal levels during steady operation. In view of characteristics and requirements of the system, a hybrid intelligent PID controller is designed specifically based on dynamic simulation. A single neuron PI controller is used for anode humidity by adjusting the water injection to the hydrogen cell. Another incremental PID controller, based on the diagonal recurrent neural network (DRNN) dynamic identification, is used to control anode pressure to be more stable and exact by adjusting the hydrogen flow rate. This control strategy can avoid the coupling problem of the PEMFC and achieve a more adaptive ability. Simulation results showed that the control strategy can maintain both anode humidity and pressure at ideal levels regardless of variable load, nonlinear dynamic and coupling characteristics of the system. This work will give some guides for further control design and applications of the total PEMFC generator.
Improved automatic tuning of PID controller for stable processes.
Kumar Padhy, Prabin; Majhi, Somanath
2009-10-01
This paper presents an improved automatic tuning method for stable processes using a modified relay in the presence of static load disturbances and measurement noise. The modified relay consists of a standard relay in series with a PI controller of unity proportional gain. The integral time constant of the PI controller of the modified relay is chosen so as to ensure a minimum loop phase margin of 30( composite function). A limit cycle is then obtained using the modified relay. Hereafter, the PID controller is designed using the limit cycle output data. The derivative time constant is obtained by maintaining the above mentioned loop phase margin. Minimizing the distance of Nyquist curve of the loop transfer function from the imaginary axis of the complex plane gives the proportional gain. The integral time constant of the PID controller is set equal to the integral time constant of the PI controller of the modified relay. The effectiveness of the proposed technique is verified by simulation results.
Multivariate respiratory motion prediction
Dürichen, R.; Wissel, T.; Ernst, F.; Schlaefer, A.; Schweikard, A.
2014-10-01
In extracranial robotic radiotherapy, tumour motion is compensated by tracking external and internal surrogates. To compensate system specific time delays, time series prediction of the external optical surrogates is used. We investigate whether the prediction accuracy can be increased by expanding the current clinical setup by an accelerometer, a strain belt and a flow sensor. Four previously published prediction algorithms are adapted to multivariate inputs—normalized least mean squares (nLMS), wavelet-based least mean squares (wLMS), support vector regression (SVR) and relevance vector machines (RVM)—and evaluated for three different prediction horizons. The measurement involves 18 subjects and consists of two phases, focusing on long term trends (M1) and breathing artefacts (M2). To select the most relevant and least redundant sensors, a sequential forward selection (SFS) method is proposed. Using a multivariate setting, the results show that the clinically used nLMS algorithm is susceptible to large outliers. In the case of irregular breathing (M2), the mean root mean square error (RMSE) of a univariate nLMS algorithm is 0.66 mm and can be decreased to 0.46 mm by a multivariate RVM model (best algorithm on average). To investigate the full potential of this approach, the optimal sensor combination was also estimated on the complete test set. The results indicate that a further decrease in RMSE is possible for RVM (to 0.42 mm). This motivates further research about sensor selection methods. Besides the optical surrogates, the sensors most frequently selected by the algorithms are the accelerometer and the strain belt. These sensors could be easily integrated in the current clinical setup and would allow a more precise motion compensation.
Multivariate Statistical Process Control
DEFF Research Database (Denmark)
Kulahci, Murat
2013-01-01
As sensor and computer technology continues to improve, it becomes a normal occurrence that we confront with high dimensional data sets. As in many areas of industrial statistics, this brings forth various challenges in statistical process control (SPC) and monitoring for which the aim...... is to identify “out-of-control” state of a process using control charts in order to reduce the excessive variation caused by so-called assignable causes. In practice, the most common method of monitoring multivariate data is through a statistic akin to the Hotelling’s T2. For high dimensional data with excessive...
Design Method for the Magnetic Bearing Control System with Fuzzy-PID Approach
Institute of Scientific and Technical Information of China (English)
XU Chun-guang; L(U) Dong-ming; HAO Juan
2008-01-01
The five degree freedom magnetic bearing is researched and its structure and working principles are introduced also.Based on the fuzzy control technology,combining fuzzy algorithm and PID control method,identifying the transition process mode of the online system to get the PID parameters'self-adjusting,the magnetic bearing system's Fuzzy-PID nonlinear controller is designed by analyzing the system control demands.The Fuzzy-PID nonlinear controller can deal with the magnetic bearing system's open loop instability and strong nonlinearity,and the approach could improve the system's rapidity,adaptability,stability and dynamic characteristics.Comparative analysis and experiments are conducted between linear PID and nonlinear fuzzyPID control methods,the results show that the fuzzy-PID controller is better,and the five-freedom magnetic bearing's rotary precision experiments are conducted by the fuzzy-PID controller,it satisfies the control rotary precision demands and realizes the bearing's steady floating and rotating.
Automatic Tuning of PID Controller for a 1-D Levitation System Using a Genetic Algorithm
DEFF Research Database (Denmark)
Yang, Zhenyu; Pedersen, Gerulf K.m.
2006-01-01
The automatic PID control design for a onedimensional magnetic levitation system is investigated. The PID controller is automatically tuned using the non-dominated sorting genetic algorithm (NSGA-II) based on a nonlinear system model. The developed controller is digitally implemented and tested...
Study of fuzzy PID controller for velocity circuit of optical-electronic theodolite
Li, GengXin; Yang, XiaoJun; He, SaiXian
2017-02-01
Two-axis stabilized turntable is an important part of optical-electronic theodolite, it carries various of measuring instruments. In order to improve the response speed of the optical-electronic theodolite when tracking high speed target. In the same time, improve the stability and precision when tracking low speed target. The traditional servo controller is double close-loop structure. On the basis of traditional structure, we use the fuzzy control theory to design the servo control speed loop adjuster as a fuzzy PID controller, and the position loop is designed as a traditional first order adjuster. We introduce the theory and characteristics of PID control and fuzzy control, and discussed the structure of the speed loop fussy controller and the tuning method of the PID parameters. The fuzzy PID controller was studied with simulation on the MATLAB/Simulink platform, the performance indexes and the anti-jamming abilities of the fussy PID controller and the traditional PID controller were compared. The experiment results show that the fussy PID controller has the ability of parameter self-tuning, and its tacking ability is much better than the traditional PID controller.
PID控制器性能评价%Performance Assessment of a PID Controller
Institute of Scientific and Technical Information of China (English)
左信; 孙金明
2005-01-01
Performance assessment of a proportional-integral-derivative (PID) controller is condueted using the PIDachievable minimum variance as a benchmark. When the process model is unknown, we can estimate the PID-achievable minimum variance and the corresponding parameters by routine closed-loop operation data. Simulation results show that the process output variance is reduced by retuning controller parameters.
基于模糊神经网络PID的液位串级控制的研究%The Study of Level Cascade Control System Based on FNN PID
Institute of Scientific and Technical Information of China (English)
王雪梅
2013-01-01
利用PID算法对液位串级系统进行控制虽然是一种有效的控制方法,但由于它的精确数学模型难以确定,使得参数整定困难、控制效果不理想.该文将PID算法、模糊控制算法以及神经网络算法相结合,形成了一种智能控制算法——模糊神经网络PID算法.将该算法运用到液位串级控制系统中,实现了PID参数的自整定,并且提高了控制质量.实验结果表明,模糊神经网络PID算法与PID算法的控制效果相比,在鲁棒性和响应时间等方面有了较大的提高,具有一定的应用前景.%Use PID algorithm level cascade control system is an effective although control method, since it's difficult to determine precise mathematical model, making parameter tuning difficulties, control effect is not ideal. This paper addresses this issue, PID algorithm, fuzzy control algorithms and neural network algorithms to form an intelligent control algorithm-FNN PID algorithm. The algorithm applied to the liquid level cascade control system, the PID parameters to achieve the self-tuning and improved quality control. The experimental results show that FNN PID algorithm and PID algorithm compared to the control results in robustness and response time and so on has been enhanced, with a certain application.
一种神经网络直接自校正PID控制器%A Type of Directly Self-tuning PID Controller Based on Neural Network
Institute of Scientific and Technical Information of China (English)
韩冲
2015-01-01
A new type of directly self-tuning PID controller based on neural network is proposed in this paper. its main characteristic is that it no longer includes independent PID controller and put neural network and the law of PID controller together. Showing the study algorithm of this neural network controller and analyzing the stability of this control system. The simulated results prove that this kind of control system is more adaptive and robust.%该文提出了一种神经网络直接自校正PID控制器。其主要特点是，在控制结构上不再包含独立的PID控制器，而是将神经网络和PID控制规律融为一体。并给出了这种神经网络控制器的学习算法和控制系统的稳定性分析。仿真结果表明，该控制系统具有较强的适应性和鲁棒性。
Design of an iterative auto-tuning algorithm for a fuzzy PID controller
Saeed, Bakhtiar I.; Mehrdadi, B.
2012-05-01
Since the first application of fuzzy logic in the field of control engineering, it has been extensively employed in controlling a wide range of applications. The human knowledge on controlling complex and non-linear processes can be incorporated into a controller in the form of linguistic terms. However, with the lack of analytical design study it is becoming more difficult to auto-tune controller parameters. Fuzzy logic controller has several parameters that can be adjusted, such as: membership functions, rule-base and scaling gains. Furthermore, it is not always easy to find the relation between the type of membership functions or rule-base and the controller performance. This study proposes a new systematic auto-tuning algorithm to fine tune fuzzy logic controller gains. A fuzzy PID controller is proposed and applied to several second order systems. The relationship between the closed-loop response and the controller parameters is analysed to devise an auto-tuning method. The results show that the proposed method is highly effective and produces zero overshoot with enhanced transient response. In addition, the robustness of the controller is investigated in the case of parameter changes and the results show a satisfactory performance.
Review, Design, Optimization and Stability Analysis of Fractional-Order PID Controller
Directory of Open Access Journals (Sweden)
Ammar SOUKKOU
2016-07-01
Full Text Available This paper will establish the importance and significance of studying the fractional-order control of nonlinear dynamical systems. The foundation and the sources related to this research scope is going to be set. Then, the paper incorporates a brief overview on how this study is performed and present the organization of this study. The present work investigates the effectiveness of the physical-fractional and biological-genetic operators to develop an Optimal Form of Fractional-order PID Controller (O2Fo-PIDC. The newly developed Fo-PIDC with optimal structure and parameters can, also, improve the performances required in the modeling and control of modern manufacturing-industrial process (MIP. The synthesis methodology of the proposed O2Fo-PIDC can be viewed as a multi-level design approach. The hierarchical Multiobjective genetic algorithm (MGA, adopted in this work, can be visualized as a combination of structural and parametric genes of a controller orchestrated in a hierarchical fashion. Then, it is applied to select an optimal structure and knowledge base of the developed fractional controller to satisfy the various design specification contradictories (simplicity, accuracy, stability and robustness.
Design of Fuzzy PID controller to control DC motor with zero overshoot
Directory of Open Access Journals (Sweden)
Meenakshi Chourasiya
2014-10-01
Full Text Available Most of the real time operation based physical system, digital PID is used in field such as servo-motor/dc motor/temperature control system, robotics, power electronics etc. need to interface with high speed constraints, higher density PLD’s such as FPGA used to integrate several logics on single IC. There are some limitations in it to overcome these limitations Fuzzy logic is introduced with PID and Fuzzy PID is formed. This paper explains experimental design of Fuzzy PID controller. We aimed to make controller power efficient, more compact, and zero overshoot. MATLAB is used to design PID controller to calculate and plot the time response of the control system and Simulink to generate a set of coefficients.
Application of Fuzzy-PID Control System in Full-Mechanized Coal Face
Institute of Scientific and Technical Information of China (English)
LU Kui; TANG Pei-rong; YANG Wei-min
2005-01-01
The control system, which includes structure, the composition of software and hardware, the form of PID control system and its systematic closed-loop, was used in No.4236 full-mechanized coal face of Xinlongzhuang mine.The typical fuzzy PID control system structure was investigated, and a simplified fuzzy PID control system was taken the place of the complex three-dimension fuzzy controller. Based on the parameter relation between fuzzy controller and normal PID controller, a common method of parameter adjustment of PID controller was summed up and the computer simulation was realized. This system can overcome the problems of large delay, nonlinear, poor running environment and great load change in the full-mechanized coal face. The simulating investigation indicates that the designing method of fuzzy controller is simple and feasible.
Mo, Qingkai; Zhang, Tao; Yan, Yining
2016-10-01
There are contradictions among speediness, anti-disturbance performance, and steady-state accuracy caused by traditional PID controller in the existing light source systems of thermal frequency stabilizing laser with double longitudinal modes. In this paper, a new kind of fuzzy adaptive PID controller was designed by combining fuzzy PID control technology and expert system to make frequency stabilizing system obtain the optimal performance. The experiments show that the frequency stability of the designed PID controller is similar to the existing PID controller (the magnitude of frequency stability is less than 10-9 in constant temperature and 10-7 in open air). But the preheating time is shortened obviously (from 10 minutes to 5 minutes) and the anti-disturbance capability is improved significantly (the recovery time needed after strong interference is reduced from 1 minute to 10 seconds).
Evaluation of PID Tuning Methods on Direct Gas-Fired Oven
Directory of Open Access Journals (Sweden)
Aborisade, D. O
2014-03-01
Full Text Available This paper studies the temperature control of gas-fired oven using PID controller. Oven control system has the characteristics of non-linearity, time delays and setpoint response. It is difficult to overcome the effects of these factors and get the satisfactory results without appropriately tuning of the PID controller gains required for stability and good transient performance. The Ziegler-Nichols closed loop, Good Gain and Skogestad’s are the PID tuning methods implemented in this paper to control the output temperature of the gas-fired oven system. The PID tuning methods are compared, based on their rise time, maximum overshoot and settling time. The performance of Skogestad’s tuning method at different temperature set point is superior to Ziegler-Nichols closed loop and Good Gain PID tuning method.
Approximation by Multivariate Singular Integrals
Anastassiou, George A
2011-01-01
Approximation by Multivariate Singular Integrals is the first monograph to illustrate the approximation of multivariate singular integrals to the identity-unit operator. The basic approximation properties of the general multivariate singular integral operators is presented quantitatively, particularly special cases such as the multivariate Picard, Gauss-Weierstrass, Poisson-Cauchy and trigonometric singular integral operators are examined thoroughly. This book studies the rate of convergence of these operators to the unit operator as well as the related simultaneous approximation. The last cha
A new control scheme for PID load frequency controller of single-area and multi-area power systems.
Padhan, Dola Gobinda; Majhi, Somanath
2013-03-01
A new control structure with a tuning method to design a PID load frequency controller for power systems is presented. Initially, the controller is designed for single area power system, then it is extended to multi-area case. The controller parameters are obtained by expanding controller transfer function using Laurent series. Relay based identification technique is adopted to estimate power system dynamics. Robustness studies on stability and performance are provided, with respect to uncertainties in the plant parameters. The proposed scheme ensures that overall system remains asymptotically stable for all bounded uncertainties and for system oscillations. Simulation results show the feasibility of the approach and the proposed method improves the load disturbance rejection performance significantly even in the presence of the uncertainties in plant parameters.
Directory of Open Access Journals (Sweden)
Amine Chouchaine
2011-01-01
Full Text Available This paper proposes a control strategy for complex and nonlinear systems, based on a parallel distributed compensation (PDC controller. A solution is presented to solve a stability problem that arises when dealing with a Takagi-Sugeno discrete system with great numbers of rules. The PDC controller will use a classical controller like a PI, PID, or RST in each rule with a pole placement strategy to avoid causing instability. The fuzzy controller presented combines the multicontrol approach and the performance of the classical controllers to obtain a robust nonlinear control action that can also deal with time-variant systems. The presented method was applied to a small greenhouse to control its inside temperature by variation in ventilation rate inside the process. The results obtained will show the efficiency of the adopted method to control the nonlinear and complex systems.
Xu, Jingying; Ren, Xiuhai; Tran, Anthony; Erdreich-Epstein, Anat
2014-01-01
BACKGROUND: Phosphotyrosine Interaction Domain containing protein-1 (PID1) was discovered in 2006. We recently showed that PID1 inhibits growth of brain tumor cell lines and its mRNA level is directly correlated with survival in glioma and medulloblastoma patients (Erdreich-Epstein et al, Clin Cancer Res). The growth-inhibitory effect of PID1 was due to decreased proliferation and increased cell death. METHODS/RESULTS: We hypothesized that PID1 sensitizes brain tumors to therapy, thus account...
Jingying Xu; Xiuhai Ren; Anup Singh Pathania; G. Esteban Fernandez; Anthony Tran; Yifu Zhang; Moats, Rex A.; Shackleford, Gregory M; Anat Erdreich-Epstein
2017-01-01
Phosphotyrosine Interaction Domain containing 1 (PID1; NYGGF4) inhibits growth of medulloblastoma, glioblastoma and atypical teratoid rhabdoid tumor cell lines. PID1 tumor mRNA levels are highly correlated with longer survival in medulloblastoma and glioma patients, suggesting their tumors may have been more sensitive to therapy. We hypothesized that PID1 sensitizes brain tumors to therapy. We found that PID1 increased the apoptosis induced by cisplatin and etoposide in medulloblastoma and gl...
Zamani, Abbas-Ali; Tavakoli, Saeed; Etedali, Sadegh
2017-03-01
Fractional order PID (FOPID) controllers are introduced as a general form of classical PID controllers using fractional calculus. As this controller provides good disturbance rejection and is robust against plant uncertainties it is appropriate for the vibration mitigation in structures. In this paper, an FOPID controller is designed to adjust the contact force of piezoelectric friction dampers for semi-active control of base-isolated structures during far-field and near-field earthquake excitations. A multi-objective cuckoo search algorithm is employed to tune the controller parameters. Considering the resulting Pareto optimal front, the best input for the FOPID controller is selected. For seven pairs of earthquakes and nine performance indices, the performance of the proposed controller is compared with those provided by several well-known control techniques. According to the simulation results, the proposed controller performs better than other controllers in terms of simultaneous reduction of the maximum base displacement and story acceleration for various types of earthquakes. Also, it provides acceptable responses in terms of inter-story drifts, root mean square of base displacements and floor acceleration. In addition, the evaluation of robustness for a stiffness uncertainty of ±10% indicates that the proposed controller gives a robust performance against such modeling errors.
Matausek, M R; Ribić, A I
2009-10-01
This paper presents an effective design and robust tuning method for the control structure based on a series PD controller and a simple Disturbance Observer. All elements of the proposed controller are directly obtained from the low-order Integrating First-Order Plus Dead-Time (IFOPDT) model, used to approximate essential dynamic characteristics of lag-dominant stable, integrating and unstable plants. The structure of the proposed controller is an effective, easy to implement and tune, extension of the series PID controller. For the same robustness, a better disturbance rejection response is obtained by the proposed controller than that of the PID, by adjusting only two parameters with a clear meaning. A comparison with well-tuned PIDs, done by simulations, and the experimental results, obtained on a real thermal power plant, confirm that high performance and robustness are obtained, for dynamic characteristics common to industrial processes.
Multivariable adaptive control of bio process
Energy Technology Data Exchange (ETDEWEB)
Maher, M.; Bahhou, B.; Roux, G. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Maher, M. [Faculte des Sciences, Rabat (Morocco). Lab. de Physique
1995-12-31
This paper presents a multivariable adaptive control of a continuous-flow fermentation process for the alcohol production. The linear quadratic control strategy is used for the regulation of substrate and ethanol concentrations in the bioreactor. The control inputs are the dilution rate and the influent substrate concentration. A robust identification algorithm is used for the on-line estimation of linear MIMO model`s parameters. Experimental results of a pilot-plant fermenter application are reported and show the control performances. (authors) 8 refs.
Multivariate Generalized Linear Mixed Models Using R
Berridge, Damon M
2011-01-01
To provide researchers with the ability to analyze large and complex data sets using robust models, this book presents a unified framework for a broad class of models that can be applied using a dedicated R package (Sabre). The first five chapters cover the analysis of multilevel models using univariate generalized linear mixed models (GLMMs). The next few chapters extend to multivariate GLMMs and the last chapters address more specialized topics, such as parallel computing for large-scale analyses. Each chapter includes many real-world examples implemented using Sabre as well as exercises and
Algorithms for computing the multivariable stability margin
Tekawy, Jonathan A.; Safonov, Michael G.; Chiang, Richard Y.
1989-01-01
Stability margin for multiloop flight control systems has become a critical issue, especially in highly maneuverable aircraft designs where there are inherent strong cross-couplings between the various feedback control loops. To cope with this issue, we have developed computer algorithms based on non-differentiable optimization theory. These algorithms have been developed for computing the Multivariable Stability Margin (MSM). The MSM of a dynamical system is the size of the smallest structured perturbation in component dynamics that will destabilize the system. These algorithms have been coded and appear to be reliable. As illustrated by examples, they provide the basis for evaluating the robustness and performance of flight control systems.
Design and Simulation of Buck Converter Based on Fuzzy PID Control%基于自整定模糊PID控制的Buck变换器设计与仿真
Institute of Scientific and Technical Information of China (English)
王淯舒; 孙培德; 吕蕾
2014-01-01
The PID controller’s structure is simple and has some characteristics of strong robustness and high reliability, but it cannot adjust PID parameters along with the change of interior parameters of the system, so that it cannot achieve optimal control. Aiming at this problem, we design a kind of PID control algorithm based on fuzzy control theory whose parameters can be self-tuning on line. The algorithm for the typical Buck converter is simulated by using Matlab2012. The simulation results show that the fuzzy PID controller can not only achieve high accuracy and high robustness control, but also can self-tuning PID parameters online.%DC-DC功率变换器在各个领域应用广泛，工业应用中大多采用PID控制。尽管PID控制具有结构简单、鲁棒性和可靠性高等特点，但PID参数不能随系统内部参数的变化而自行调整，导致无法达到最优控制。为此，设计一种基于模糊控制理论的、可在线自整定参数的PID算法，并用Matlab2012对典型Buck变换器和模糊自整定PID算法仿真。结果表明：模糊PID控制器既可实现高精度、高鲁棒性控制，又能完成PID参数的在线自整定。
Low rank Multivariate regression
Giraud, Christophe
2010-01-01
We consider in this paper the multivariate regression problem, when the target regression matrix $A$ is close to a low rank matrix. Our primary interest in on the practical case where the variance of the noise is unknown. Our main contribution is to propose in this setting a criterion to select among a family of low rank estimators and prove a non-asymptotic oracle inequality for the resulting estimator. We also investigate the easier case where the variance of the noise is known and outline that the penalties appearing in our criterions are minimal (in some sense). These penalties involve the expected value of the Ky-Fan quasi-norm of some random matrices. These quantities can be evaluated easily in practice and upper-bounds can be derived from recent results in random matrix theory.
Analog multivariate counting analyzers
Nikitin, A V; Armstrong, T P
2003-01-01
Characterizing rates of occurrence of various features of a signal is of great importance in numerous types of physical measurements. Such signal features can be defined as certain discrete coincidence events, e.g. crossings of a signal with a given threshold, or occurrence of extrema of a certain amplitude. We describe measuring rates of such events by means of analog multivariate counting analyzers. Given a continuous scalar or multicomponent (vector) input signal, an analog counting analyzer outputs a continuous signal with the instantaneous magnitude equal to the rate of occurrence of certain coincidence events. The analog nature of the proposed analyzers allows us to reformulate many problems of the traditional counting measurements, and cast them in a form which is readily addressed by methods of differential calculus rather than by algebraic or logical means of digital signal processing. Analog counting analyzers can be easily implemented in discrete or integrated electronic circuits, do not suffer fro...
Multivariate statistical methods a primer
Manly, Bryan FJ
2004-01-01
THE MATERIAL OF MULTIVARIATE ANALYSISExamples of Multivariate DataPreview of Multivariate MethodsThe Multivariate Normal DistributionComputer ProgramsGraphical MethodsChapter SummaryReferencesMATRIX ALGEBRAThe Need for Matrix AlgebraMatrices and VectorsOperations on MatricesMatrix InversionQuadratic FormsEigenvalues and EigenvectorsVectors of Means and Covariance MatricesFurther Reading Chapter SummaryReferencesDISPLAYING MULTIVARIATE DATAThe Problem of Displaying Many Variables in Two DimensionsPlotting index VariablesThe Draftsman's PlotThe Representation of Individual Data P:ointsProfiles o
Xu, Jingying; Ren, Xiuhai; Tran, Anthony; Erdreich-Epstein, Anat
2014-01-01
BACKGROUND: Phosphotyrosine Interaction Domain containing protein-1 (PID1) was discovered in 2006. We recently showed that PID1 inhibits growth of brain tumor cell lines and its mRNA level is directly correlated with survival in glioma and medulloblastoma patients (Erdreich-Epstein et al, Clin Cancer Res). The growth-inhibitory effect of PID1 was due to decreased proliferation and increased cell death. METHODS/RESULTS: We hypothesized that PID1 sensitizes brain tumors to therapy, thus accounting for the longer survival in patients with higher PID1 mRNA. Indeed, while cisplatin (10 µg/ml) or transient PID1 overexpression each increased apoptosis of glioma and medulloblastoma cell lines, combining cisplatin with PID1 resulted in markedly higher apoptosis. Moreover, knockdown of PID1 by siRNA inhibited the cisplatin-induced mitochondrial membrane depolarization and apoptosis, suggesting that PID1 is partially required for cisplatin-induced apoptosis. Taken together, this suggests that PID1 sensitizes both glioma and medulloblastoma cell lines to cisplatin. Intriguingly, PID1 mRNA increased in response to chemotherapy in a time- and dose-dependent manner in brain tumor cell lines. The chemotherapy-induced increase in PID1 mRNA was blocked by inhibitors of NFkB, suggesting that regulation of PID1 mRNA increase may be an NF-kB-dependent process. Consistent with this, cisplatin increased activity of an NF-kB promoter reporter. Surprisingly, despite the chemotherapy-induced increase in PID1 mRNA, PID1 protein decreased in response to cisplatin, suggesting post-translational modification(s) of PID1 induced by cisplatin. Ongoing work is focusing on the mechanism and role of PID1 in response to chemotherapy, and examining the effect of PID1 on the response of tumors to chemotherapy in vivo. CONCLUSIONS: Our data show that PID1 sensitizes glioma and medulloblastoma cell lines to chemotherapy, possibly explaining the correlation between higher PID1 mRNA and longer patient
Automatic PID Parameter Tuning Based on Unfalsified Control%基于去伪控制的 PID 自适应参数调节
Institute of Scientific and Technical Information of China (English)
姚烯; 刘春生; 王晓霞
2014-01-01
Traditional robust control and adaptive control are based on the accurate models .They can only control the systems with small enough or constant uncertainty .An unfalsified control based on the data driving is proposed to overcome the shortcoming,which is one type of model-free adaptive control .The proposed method is data-driven and doesn ’ t rely on system model .The designed controller is simple and is highly adaptable to online application .In this paper,the basic theory of unfalsified control is introduced and applied to real-time PID controller parameter tuning and adaptation .Simulation is also conducted when there is disturbance with the system .The result shows that the algorithm is actually fairly robust to noise and perturbation .The feasibility and effectiveness of this algorithm are also proved by the simulation result .%针对传统的鲁棒控制和自适应控制都是基于精确模型的控制设计思想，仅仅能够实现对含有足够小的或者恒定不确定性的系统进行控制的弱点，提出了一种基于数据的无模型自适应控制方法---去伪控制。该方法只需利用采集的数据，不依赖于系统模型，所设计的控制器形式简单，适合实时在线应用。介绍了该控制方法的基本理论，将其应用到实时PID参数自适应调节上，并在系统有干扰的情况下进行了仿真研究。仿真结果表明，该算法在系统扰动的情况下具有很好的鲁棒性，研究结果表明了该控制方法的可行性和有效性。
Speed Control of Bldc Motor Drive By Using Pid Controllers
Directory of Open Access Journals (Sweden)
Y.Narendra Kumar,
2014-04-01
Full Text Available This paper mainly deals with the Brushless DC (BLDC motor speed driving systems have sprouted in various small scale and large scale applications like automobile industries, domestic appliances etc. This leads to the development in Brushless DC motor (BLDCM. The usage of BLDC Motor enhances various performance factors ranging from higher efficiency, higher torque in low-speed range, high power density ,low maintenance and less noise than other motors. The BLDC Motor can act as an alternative for traditional motors like induction and switched reluctance motors. In this paper PID controller is implemented with speed feedback loop and it is observe that torque ripples are minimized. Simulation is carried out using MATLAB / SIMULINK. The results show that the performance of BLDC Motor is quite satisfactory for various loading conditions. Brushless DC motor drives are typically employed in speed controlled applications.
Optimization of PID Controllers Using Ant Colony and Genetic Algorithms
Ünal, Muhammet; Topuz, Vedat; Erdal, Hasan
2013-01-01
Artificial neural networks, genetic algorithms and the ant colony optimization algorithm have become a highly effective tool for solving hard optimization problems. As their popularity has increased, applications of these algorithms have grown in more than equal measure. While many of the books available on these subjects only provide a cursory discussion of theory, the present book gives special emphasis to the theoretical background that is behind these algorithms and their applications. Moreover, this book introduces a novel real time control algorithm, that uses genetic algorithm and ant colony optimization algorithms for optimizing PID controller parameters. In general, the present book represents a solid survey on artificial neural networks, genetic algorithms and the ant colony optimization algorithm and introduces novel practical elements related to the application of these methods to process system control.
OPTIMAL-TUNING OF PID CONTROLLER GAINS USING GENETIC ALGORITHMS
Directory of Open Access Journals (Sweden)
Ömer GÜNDOĞDU
2005-01-01
Full Text Available This paper presents a method of optimum parameter tuning of a PID controller to be used in driving an inertial load by a dc motor thorough a gearbox. Specifically, the method uses genetic algorithms to determine the optimum controller parameters by minimizing the sum of the integral of the squared error and the squared controller output deviated from its steady state value. The paper suggests the use of Ziegler-Nichols settings to form the intervals for the controller parameters in which the population to be formed. The results obtained from the genetic algorithms are compared with the ones from Ziegler-Nichols in both figures and tabular form. Comparatively better results are obtained in the genetic algorithm case.
Gain Scheduling of PID Controller Based on Fuzzy Systems
Directory of Open Access Journals (Sweden)
Singh Sandeep
2016-01-01
Full Text Available This paper aims to utilize fuzzy rules and reasoning to determine the controller parameters and the PID controller generates the control signal. The objective of this study is to simulate the proposed scheme on various processes and arrive at results providing better response of the system when compared with best industrial auto-tuning technique: Ziegler-Nichols. The proposed scheme is based upon the Ultimate Gain (Ku and the Period (Tu of the system. The error and rate of change in error gains are tuned manually to get the desired response using LabVIEW. This can also be done with various optimization techniques. A thumb rule for choosing the ranges for Kc, Kd and Ki has been obtained experimentally.
Intelligent PID guidance control for AUV path tracking
Institute of Scientific and Technical Information of China (English)
李晔; 姜言清; 王磊峰; 曹建; 张国成
2015-01-01
Based on rational behavior model of three layers, a tracking control system is designed for straight line tracking which is commonly used in underwater survey missions. An intelligent PID control law implemented as planning level during the control system using transverse deviation is came up with. Continuous tracking of path expressed by a point sequence can be realized by the law. Firstly, a path tracking control system based on rational behavior model of three layers is designed, mainly satisfying the needs of underactuated AUV. Since there is no need to perform spatially coupled maneuvers, the 3D path tracking control is decoupled into planar 2D path tracking and depth or height tracking separately. Secondly, planar path tracking controller is introduced. For the reason that more attention is paid to comparing with vertical position control, transverse deviation in analytical form is derived. According to the Lyapunov direct theory, control law is designed using discrete PID algorithm whose parameters obey adaptive fuzzy adjustment. Reference heading angle is given as an output of the guidance controller conducted by lateral deviation together with its derivative. For the purpose of improving control quality and facilitating parameter modifying, data normalize modules based on Sigmoid function are applied to input-output data manipulation. Lastly, a sequence of experiments was carried out successfully, including tests in Longfeng lake and at the Yellow sea. In most challenging sea conditions, tracking errors of straight line are below 2 m in general. The results show that AUV is able to compensate the disturbance brought by sea current. The provided test results demonstrate that the designed guidance controller guarantees stably and accurately straight route tracking. Besides, the proposed control system is accessible for continuous comb-shaped path tracking in region searching.
Position Control of Pneumatic Actuator Using Self-Regulation Nonlinear PID
Directory of Open Access Journals (Sweden)
Syed Najib Syed Salim
2014-01-01
Full Text Available The enhancement of nonlinear PID (N-PID controller for a pneumatic positioning system is proposed to improve the performance of this controller. This is executed by utilizing the characteristic of rate variation of the nonlinear gain that is readily available in N-PID controller. The proposed equation, namely, self-regulation nonlinear function (SNF, is used to reprocess the error signal with the purpose of generating the value of the rate variation, continuously. With the addition of this function, a new self-regulation nonlinear PID (SN-PID controller is proposed. The proposed controller is then implemented to a variably loaded pneumatic actuator. Simulation and experimental tests are conducted with different inputs, namely, step, multistep, and random waveforms, to evaluate the performance of the proposed technique. The results obtained have been proven as a novel initiative at examining and identifying the characteristic based on a new proposal controller resulting from N-PID controller. The transient response is improved by a factor of 2.2 times greater than previous N-PID technique. Moreover, the performance of pneumatic positioning system is remarkably good under various loads.
Directory of Open Access Journals (Sweden)
S. J. Bassi
2011-10-01
Full Text Available The proportional-integral-derivative (PID controllers are the most popular controllers used in industry because of their remarkable effectiveness, simplicity of implementation and broad applicability. However, manual tuning of these controllers is time consuming, tedious and generally lead to poor performance. This tuning which is application specific also deteriorates with time as a result of plant parameter changes. This paper presents an artificial intelligence (AI method of particle swarm optimization (PSO algorithm for tuning the optimal proportional-integral derivative (PID controller parameters for industrial processes. This approach has superior features, including easy implementation, stable convergence characteristic and good computational efficiency over the conventional methods. Ziegler- Nichols, tuning method was applied in the PID tuning and results were compared with the PSO-Based PID for optimum control. Simulation results are presented to show that the PSO-Based optimized PID controller is capable of providing an improved closed-loop performance over the Ziegler- Nichols tuned PID controller Parameters. Compared to the heuristic PID tuning method of Ziegler-Nichols, the proposed method was more efficient in improving the step response characteristics such as, reducing the steady-states error; rise time, settling time and maximum overshoot in speed control of DC motor.
Cardiac-Specific PID1 Overexpression Enhances Pressure Overload-Induced Cardiac Hypertrophy in Mice
Directory of Open Access Journals (Sweden)
Yaoqiu Liu
2015-03-01
Full Text Available Background/Aims: PID1 was originally described as an insulin sensitivity relevance protein, which is also highly expressed in heart tissue. However, its function in the heart is still to be elucidated. Thus this study aimed to investigate the role of PID1 in the heart in response to hypertrophic stimuli. Methods: Samples of human failing hearts from the left ventricles of dilated cardiomyopathy (DCM patients undergoing heart transplants were collected. Transgenic mice with cardiomyocyte-specific overexpression of PID1 were generated, and cardiac hypertrophy was induced by transverse aortic constriction (TAC. The extent of cardiac hypertrophy was evaluated by echocardiography as well as pathological and molecular analyses of heart samples. Results: A significant increase in PID1 expression was observed in failing human hearts and TAC-treated wild-type mouse hearts. When compared with TAC-treated wild-type mouse hearts, PID1-TG mouse showed a significant exacerbation of cardiac hypertrophy, fibrosis, and dysfunction. Further analysis of the signaling pathway in vivo suggested that these adverse effects of PID1 were associated with the inhibition of AKT, and activation of MAPK pathway. Conclusion: Under pathological conditions, over-expression of PID1 promotes cardiac hypertrophy by regulating the Akt and MAPK pathway.
Cardiac-specific PID1 overexpression enhances pressure overload-induced cardiac hypertrophy in mice.
Liu, Yaoqiu; Shen, Yahui; Zhu, Jingai; Liu, Ming; Li, Xing; Chen, Yumei; Kong, Xiangqing; Song, Guixian; Qian, Lingmei
2015-01-01
PID1 was originally described as an insulin sensitivity relevance protein, which is also highly expressed in heart tissue. However, its function in the heart is still to be elucidated. Thus this study aimed to investigate the role of PID1 in the heart in response to hypertrophic stimuli. Samples of human failing hearts from the left ventricles of dilated cardiomyopathy (DCM) patients undergoing heart transplants were collected. Transgenic mice with cardiomyocyte-specific overexpression of PID1 were generated, and cardiac hypertrophy was induced by transverse aortic constriction (TAC). The extent of cardiac hypertrophy was evaluated by echocardiography as well as pathological and molecular analyses of heart samples. A significant increase in PID1 expression was observed in failing human hearts and TAC-treated wild-type mouse hearts. When compared with TAC-treated wild-type mouse hearts, PID1-TG mouse showed a significant exacerbation of cardiac hypertrophy, fibrosis, and dysfunction. Further analysis of the signaling pathway in vivo suggested that these adverse effects of PID1 were associated with the inhibition of AKT, and activation of MAPK pathway. Under pathological conditions, over-expression of PID1 promotes cardiac hypertrophy by regulating the Akt and MAPK pathway. © 2015 S. Karger AG, Basel.
Salat, Robert; Awtoniuk, Michal
In this report, the parameters identification of a proportional-integral-derivative (PID) algorithm implemented in a programmable logic controller (PLC) using support vector regression (SVR) is presented. This report focuses on a black box model of the PID with additional functions and modifications provided by the manufacturers and without information on the exact structure. The process of feature selection and its impact on the training and testing abilities are emphasized. The method was tested on a real PLC (Siemens and General Electric) with the implemented PID. The results show that the SVR maps the function of the PID algorithms and the modifications introduced by the manufacturer of the PLC with high accuracy. With this approach, the simulation results can be directly used to tune the PID algorithms in the PLC. The method is sufficiently universal in that it can be applied to any PI or PID algorithm implemented in the PLC with additional functions and modifications that were previously considered to be trade secrets. This method can also be an alternative for engineers who need to tune the PID and do not have any such information on the structure and cannot use the default settings for the known structures.
Robust Geometric Control of a Distillation Column
DEFF Research Database (Denmark)
Kymmel, Mogens; Andersen, Henrik Weisberg
1987-01-01
A frequency domain method, which makes it possible to adjust multivariable controllers with respect to both nominal performance and robustness, is presented. The basic idea in the approach is that the designer assigns objectives such as steady-state tracking, maximum resonance peaks, bandwidth, m...... is used to examine and improve geometric control of a binary distillation column....
Joint Sparsity-Based Robust Multimodal Biometrics Recognition
2012-10-07
joint sparsity-based algorithm for multimodal biometrics recognition. Our method is based on the well known regu- larized regression method, multi-task...multivariate Lasso [7, 8]. Figure. 1 presents an overview of our method. This paper makes the following contributions: – We present a robust feature...reduces to the conventional Lasso [10] when D = 1 and d = 1. For D = 1 (1), it is equivalent to multivariate Lasso [7]. 2.2 Robust Multimodal
Modelling and Control of the Qball X4 Quadrotor System based on Pid and Fuzzy Logic Structure
Bodrumlu, Tolga; Turan Soylemez, Mehmet; Mutlu, Ilhan
2017-01-01
This work focuses on a quadrocopter model, which was developed by QuanserTM and named as Qball X4. First, mathematical model of the Qball X4 is obtained. Then, a conventional PID control technique is presented. This PID control parameters come from Qball user manual. After the presentation of conventional PID control, as an extension of the conventional PID control theory, a different fuzzy controller structure is given. The proposed fuzzy controller structure is based on fuzzy logic and its name is PID type fuzzy controller. All of the simulations are done in MATLABTM environment.
Study of Dynamic Robustness of Servo Control System on a Water Press
Institute of Scientific and Technical Information of China (English)
KONG Xiangdong; YAO Jing; GAO Yingjie; ZHANG Qin
2006-01-01
The reliability and robustness of the electro-hydraulic servo control system for heavy-duty forging machine play an important role in forging processes. A mathematic model of 50 MN water press for free forging was created in this research. The dynamic robust compensator integrating with PID control method is designed and applied to the mathematical model simulation. The simulated results approved that the dynamic robust compensator application restrains interference from extra load and improves the electro-hydraulic position servo control system accuracy and stability.
PID Neural Network Decoupling Control Based on Particle Swarm Optimization%基于粒子群算法的PID神经网络解耦控制
Institute of Scientific and Technical Information of China (English)
周西峰; 林莹莹; 郭前岗
2013-01-01
基于粒子群的优化算法具有对整个参数空间进行高效并行搜索的特点以及PID神经网络的自调节和自适应特性，设计了具有PID结构的多变量自适应神经网络控制器。该算法采用粒子群算法优化PID神经网络初始权值，并将优化后的最优初始权值控制非线性耦合系统。系统仿真结果表明，粒子群优化后的PID神经网络控制器具有逼近控制目标更快、响应时间较短的显著优点。该控制策略可在大范围内克服系统的非线性和强耦合问题，具有一定的理论研究价值和工程实用价值。%The automatic control of such a system is a research focus in the process control area. A multivariable adaptive PID Artificial Neural Network ( ANN) controller was introduced,which was based on the characteristics of Particle Swarm Optimization ( PSO) algo-rithm searching the parameter space concurrently and efficiently,and the self-regulation and adaptability of PID artificial neuron net-works. Utilize the PSO to optimize the initial weight value of PID neural network,successfully achieve the control strategy of a nonlinear coupling system using the improved PID neural network with those obtained from the original PID neural network. The new control strate-gy could overcome nonlinear and strong coupling features of the system in a wide range and is expected to have certain theoretical and en-gineering application value.
Multi-Objective PID-Controller Tuning for a Magnetic Levitation System using NSGA-II
DEFF Research Database (Denmark)
Pedersen, Gerulf K. M.; Yang, Zhenyu
2006-01-01
This paper investigates the issue of PID-controller parameter tuning for a magnetic levitation system using the non-dominated sorting genetic algorithm (NSGA-II). The magnetic levitation system is inherently unstable and the PID-controller parameters are hard to find using conventional methods....... Based on four different performance measures, derived from the step response of the levitation system, the algorithm is used to find a set of non-dominated parameters for a PID-controller that can stabilize the system and minimize the performance measures....
PID feedback for mixed H2/H∞ tracking control of robotic manipulators
Institute of Scientific and Technical Information of China (English)
黄春庆; 施颂椒
2004-01-01
The design objective of a mixed H2/H∞ control is to find the H2 optimal control law under aprescribed disturbance attenuation level. This paper addresses a optimal PID control law on the basis of the newsolution to mixed H2/H∞optimal control problem that provide much more flexible design compared to the existing works. Then a closed-form PID controller to mixed H2/H∞ robotic tracking problem is simply constructed and hence the design procedure is presented.Finally, numerical simulations illustrate the effectiveness of the optimal PID feedback design proposed in this paper via a two-link robotic manipulator.
Research on the controller of an arc welding process based on a PID neural network
Institute of Scientific and Technical Information of China (English)
Kuanfang HE; Shisheng HUANG
2008-01-01
A controller based on a PID neural network(PIDNN)is proposed for an arc welding power source whose output characteristic in responding to a given value is quickly and intelligently controlled in the welding process.The new method syncretizes the PID control strategy and neural network to control the welding process intelligently,so it has the merit of PID control rules and the trait of better information disposal ability of the neural network.The results of simulation show that the controller has the properties of quick response,low overshoot quick convergence and good stable accuracy,which meet the requirements for control of the welding process.
PID and predictive control of electrical drives and power converters using MATLAB/Simulink
Wang, Liuping; Yoo, Dae; Gan, Lu; Ng, Ki
2015-01-01
A timely introduction to current research on PID and predictive control by one of the leading authors on the subject PID and Predictive Control of Electric Drives and Power Supplies using MATLAB/Simulink examines the classical control system strategies, such as PID control, feed-forward control and cascade control, which are widely used in current practice. The authors share their experiences in actual design and implementation of the control systems on laboratory test-beds, taking the reader from the fundamentals through to more sophisticated design and analysis. The book contains secti
Prakash, J; Srinivasan, K
2009-07-01
In this paper, the authors have represented the nonlinear system as a family of local linear state space models, local PID controllers have been designed on the basis of linear models, and the weighted sum of the output from the local PID controllers (Nonlinear PID controller) has been used to control the nonlinear process. Further, Nonlinear Model Predictive Controller using the family of local linear state space models (F-NMPC) has been developed. The effectiveness of the proposed control schemes has been demonstrated on a CSTR process, which exhibits dynamic nonlinearity.
Novel Approach to Nonlinear PID Parameter Optimization Using Ant Colony Optimization Algorithm
Institute of Scientific and Technical Information of China (English)
Duan Hai-bin; Wang Dao-bo; Yu Xiu-fen
2006-01-01
This paper presents an application of an Ant Colony Optimization (ACO) algorithm to optimize the parameters in the design of a type of nonlinear PID controller. The ACO algorithm is a novel heuristic bionic algorithm, which is based on the behaviour of real ants in nature searching for food. In order to optimize the parameters of the nonlinear PID controller using ACO algorithm,an objective function based on position tracing error was constructed, and elitist strategy was adopted in the improved ACO algorithm. Detailed simulation steps are presented. This nonlinear PID controller using the ACO algorithm has high precision of control and quick response.
The Research of PID Control in a Large Scale Helium Refrigerator
Pan, W.; Wu, J. H.; Li, L. F.; Liu, H. M.; Li, Q.
2015-12-01
In the development of a helium refrigerator, the control of load temperature stability is an important requirement. We usually use multistage control strategies to achieve the precise control of it. Each level has its strict control logic. PID controllers are the core control module in the process. Therefore, a research of its principle and parameters’ setting occupies an important position in the development work. This paper detailed describes the PID control principle used in a large scale helium refrigerator of 10kW@20K, as well as several improvements on PID parameters’ setting, by using simulations and experiments in combination. The temperature is eventually controlled more precise.
An effective frequency domain approach to tuning non-PID controllers for high performance.
Wang, Qing-Guo; Ru, He; Huang, Xiao-Gang
2002-01-01
In this paper, a new tuning method is proposed for the design of non-PID controllers for complex processes to achieve high performance. Compared with the existing PID tuning methods, the proposed non-PID controller design method can yield better performance for a wide range of complex processes. A suitable objective transfer function for the closed-loop system is chosen according to process characteristics. The corresponding ideal controller is derived. Model reduction is applied to fit the ideal controller into a much simpler and realizable form. Stability analysis is given and simulation examples are provided to demonstrate the effectiveness of the proposed method.
Directory of Open Access Journals (Sweden)
Benxian Xiao
2014-06-01
Full Text Available Proposed the PID controller parameters tuning method based-on New Luus-Jaakola (NLJ algorithm and satisfaction idea. According to the different requirements of each performance index, designed the satisfaction function with fuzzy constraint attributes, and then determined the comprehensive satisfaction function for PID tuning by NLJ algorithm. Provided the steps of PID controller parameters tuning based on the NLJ algorithm and satisfaction, and applied this tuning method to the cascade control system of superheated steam temperature for Power Station Boiler. Finally the simulation and experiment results have shown the proposed method has good dynamic and static control performances for this complicated superheated steam temperature control system.
Expression and purification of porcine PID1 gene in Escherichia coli
Wang, Huan; Chen, Xiaoling; Huang, Zhiqing; ZHOU, BO; Jia, Gang; Liu, Guangmang; Zhao, Hua
2014-01-01
In this study, in order to scale up the production of recombinant porcine phosphotyrosine interaction domain containing 1 (pPID1), a pET-28a (+)-pPID1 expression plasmid was constructed and transformed into Escherichia coli Rosetta (DE3). The recombinant pPID1 was then purified and identified by western blotting, and was also analyzed in vitro for its function. The recombinant protein was tagged with only a His6 tag at its C-terminus, which could be conveniently purified by affinity column. T...
Gamma spectroscopic measurements using the PID350 pixelated CdTe radiation detector
Karafasoulis, K; Seferlis, S; Papadakis, I; Loukas, D; Lambropoulos, C; Potiriadis, C
2010-01-01
Spectroscopic measurements are presented using the PID350 pixelated gamma radiation detectors. A high-speed data acquisition system has been developed in order to reduce the data loss during the data reading in case of a high flux of photons. A data analysis framework has been developed in order to improve the resolution of the acquired energy spectra, using specific calibration parameters for each PID350's pixel. Three PID350 detectors have been used to construct a stacked prototype system and spectroscopic measurements have been performed in order to test the ability of the prototype to localize radioactive sources.
Hou, Yi-You
2017-09-01
This article addresses an evolutionary programming (EP) algorithm technique-based and proportional-integral-derivative (PID) control methods are established to guarantee synchronization of the master and slave Rikitake chaotic systems. For PID synchronous control, the evolutionary programming (EP) algorithm is used to find the optimal PID controller parameters kp, ki, kd by integrated absolute error (IAE) method for the convergence conditions. In order to verify the system performance, the basic electronic components containing operational amplifiers (OPAs), resistors, and capacitors are used to implement the proposed chaotic Rikitake systems. Finally, the experimental results validate the proposed Rikitake chaotic synchronization approach. Copyright © 2017. Published by Elsevier Ltd.
Didactic System for the Experimental Study of Digital PID Control Structures
Directory of Open Access Journals (Sweden)
Stelian-Emilian OLTEAN
2016-12-01
Full Text Available The proportional integral derivative (PID controller has a known structure used in feedback control of industrial processes. One of the most common applications is the control of the DC motor. The paper presents a didactic system designed for educational purposes used for studying various conventional PID structures and the influence of the PID components in the control process of the DC motor’s speed. The system contains a low cost acquisition board based on PIC 16F628A microcontroller. The experimental results are shown graphically using a PC application made in Matlab environment.
Multivariate statistics exercises and solutions
Härdle, Wolfgang Karl
2015-01-01
The authors present tools and concepts of multivariate data analysis by means of exercises and their solutions. The first part is devoted to graphical techniques. The second part deals with multivariate random variables and presents the derivation of estimators and tests for various practical situations. The last part introduces a wide variety of exercises in applied multivariate data analysis. The book demonstrates the application of simple calculus and basic multivariate methods in real life situations. It contains altogether more than 250 solved exercises which can assist a university teacher in setting up a modern multivariate analysis course. All computer-based exercises are available in the R language. All R codes and data sets may be downloaded via the quantlet download center www.quantlet.org or via the Springer webpage. For interactive display of low-dimensional projections of a multivariate data set, we recommend GGobi.
Compressive tracking with incremental multivariate Gaussian distribution
Li, Dongdong; Wen, Gongjian; Zhu, Gao; Zeng, Qiaoling
2016-09-01
Various approaches have been proposed for robust visual tracking, among which compressive tracking (CT) yields promising performance. In CT, Haar-like features are efficiently extracted with a very sparse measurement matrix and modeled as an online updated naïve Bayes classifier to account for target appearance change. The naïve Bayes classifier ignores overlap between Haar-like features and assumes that Haar-like features are independently distributed, which leads to drift in complex scenario. To address this problem, we present an extended CT algorithm, which assumes that all Haar-like features are correlated with each other and have multivariate Gaussian distribution. The mean vector and covariance matrix of multivariate normal distribution are incrementally updated with constant computational complexity to adapt to target appearance change. Each frame is associated with a temporal weight to expend less modeling power on old observation. Based on temporal weight, an update scheme with changing but convergent learning rate is derived with strict mathematic proof. Compared with CT, our extended algorithm achieves a richer representation of target appearance. The incremental multivariate Gaussian distribution is integrated into the particle filter framework to achieve better tracking performance. Extensive experiments on the CVPR2013 tracking benchmark demonstrate that our proposed tracker achieves superior performance both qualitatively and quantitatively over several state-of-the-art trackers.
DEFF Research Database (Denmark)
Sørensen, John Dalsgaard
2011-01-01
robust design as well as strategies for maintaining the robustness of existing structures throughout their service life. This paper describes an overall theoretical framework for assessing robustness of structures developed within WG1 “Robustness of structures”. Robustness can be defined in different......An important aspect of the COST Action TU0601 “Robustness of structures” concerns the development of a theoretically sound basis for the assessment of robustness and acceptance criteria for structural robustness which can form the basis for development of practical relevant methods for ensuring...
Method study on fuzzy-PID adaptive control of electric-hydraulic hitch system
Li, Mingsheng; Wang, Liubu; Liu, Jian; Ye, Jin
2017-03-01
In this paper, fuzzy-PID adaptive control method is applied to the control of tractor electric-hydraulic hitch system. According to the characteristics of the system, a fuzzy-PID adaptive controller is designed and the electric-hydraulic hitch system model is established. Traction control and position control performance simulation are carried out with the common PID control method. A field test rig was set up to test the electric-hydraulic hitch system. The test results showed that, after the fuzzy-PID adaptive control is adopted, when the tillage depth steps from 0.1m to 0.3m, the system transition process time is 4s, without overshoot, and when the tractive force steps from 3000N to 7000N, the system transition process time is 5s, the system overshoot is 25%.
PID Controller Optimization by GA and Its Performances on the Electro-hydraulic Servo Control System
Institute of Scientific and Technical Information of China (English)
Karam M. Eibayomy; Jiao Zongxia; Zhang Huaqing
2008-01-01
A proportional integral derivative (PID) controller is designed and attached to electro-hydraulic servo actuator system (EHSAS) to control the angular position of the rotary actuator which control the movable surface of space vehicles. The PID gain parameters areoptimized by the genetic algorithm (GA). The controller is verified on the new state-space model of servo-valves attached to the physical rotary actuator by SIMULINK program. The controller and the state-space model are verified experimentally. Simulation and experimental results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as compared with the classical PID controller and the compensator controller.
Fractional order PID controller for improvement of PMSM speed control in aerospace applications
Energy Technology Data Exchange (ETDEWEB)
Saraji, Ali Motalebi [Young Researchers and Elite Club, AliAbad Katoul Branch, Islamic Azad University, AliAbad Katoul (Iran, Islamic Republic of); Ghanbari, Mahmood [Department of Electrical Engineering, AliAbad Katoul Branch, Islamic Azad University, AliAbad Katoul (Iran, Islamic Republic of)
2014-12-10
Because of the benefits reduced size, cost and maintenance, noise, CO2 emissions and increased control flexibility and precision, to meet these expectations, electrical equipment increasingly utilize in modern aircraft systems and aerospace industry rather than conventional mechanic, hydraulic, and pneumatic power systems. Electric motor drives are capable of converting electrical power to drive actuators, pumps, compressors, and other subsystems at variable speeds. In the past decades, permanent magnet synchronous motor (PMSM) and brushless dc (BLDC) motor were investigated for aerospace applications such as aircraft actuators. In this paper, the fractional-order PID controller is used in the design of speed loop of PMSM speed control system. Having more parameters for tuning fractional order PID controller lead to good performance ratio to integer order. This good performance is shown by comparison fractional order PID controller with the conventional PI and tuned PID controller by Genetic algorithm in MATLAB soft wear.
Optimization of PID Controller for Brushless DC Motor by using Bio-inspired Algorithms
National Research Council Canada - National Science Library
Sanjay Kr. Singh; Nitish Katal; S.G. Modani
2014-01-01
This study presents the use and comparison of various bio-inspired algorithms for optimizing the response of a PID controller for a Brushless DC Motor in contrast to the conventional methods of tuning...
Design of fuzzy PID controller for high temperature pebble bed reactor
Energy Technology Data Exchange (ETDEWEB)
Badgujar, Kushal D.; Satpute, Satchidanand R.; Revankara, Shripad T.; Lee, John C.; Kim, Moo Hwan [POSTECH, Pohang (Korea, Republic of)
2012-10-15
Control system is most important characteristic to be considered to control spontaneous fission reaction in the design of the nuclear reactor. Recently fuzzy based control systems have been designed and applied as control system for nuclear plants. This article emphasize on controlling the power of the high temperature pebble bed reactor (HTPBR) with the design of Fuzzy proportional integral derivative (PID) controller. A simplified reactor model with point kinetics equation and reactor heat balance equation is used. The reactivity feedback arising from power coefficient of reactivity and Xenon poisoning is also considered. The reactor is operated at various power levels by using fuzzy PID controller. The fuzzy logic eliminates the necessity of the tuning the gains of PID controller each time by extending the finite sets of the PID controller gains.
Position Control of a Serial Manipulator Using Fuzzy-PID Controllers
Directory of Open Access Journals (Sweden)
Yong-Lin Kuo
2015-02-01
Full Text Available This paper presents the position control of a six-axis serial manipulator by using a fuzzy-PID controller. The manipulator has six joints, and each joint is driven by a motor with an encoder for sensing the joint angle. To complete a position movement of the end-effector of the manipulator, the position coordinate first needs to be converted to a sets of joint angles by using the inverse kinematics of the manipulator, and each joint rotation is executed by a feedback control of a motor. To demonstrate the performance the fuzzy-PID controller, a PID controller and two fuzzy controllers are also applied. The results show that the fuzzy-PID controller provides a better performance with a smaller steady-state error.
Integrated tuning of PID-derivative load frequency controller for two ...
African Journals Online (AJOL)
DR OKE
International Journal of Engineering, Science and Technology. Vol. 7, No. 3, 2010, pp. 42-51 ..... T Hydro turbine speed governor main servo time constant, s. PS. T .... Optimal-tuning nonlinear PID control of hydraulic systems. Control Engg.
Research of Self-Tuning PID for PMSM Vector Control based on Improved KMTOA
National Research Council Canada - National Science Library
Lingzhi Yi; Chengdong Zhang; Genping Wang
2017-01-01
.... In order to realize the control of the PMSM accurately, a novel adaptive chaotic kinetic molecular theory optimization algorithm was implemented for seeking the best parameters of PID controller...
Directory of Open Access Journals (Sweden)
Mohammad Marefati
2016-06-01
Full Text Available In this article, an optimized PID controller for a fuel cell is introduced. It should be noted that we did not compute the PID controller’s coefficients based on trial-and-error method; instead, imperialist competitive algorithms have been considered. At first, the problem will be formulated as an optimization problem and solved by the mentioned algorithm, and optimized results will be obtained for PID coefficients. Then one of the important kinds of fuel cells, called proton exchange membrane fuel cell, is introduced. In order to control the voltage of this fuel cell during the changes in the charges, an optimal controller is introduced, based on the imperialist competitive algorithm. In order to apply this algorithm, the problem is written as an optimization problem which includes objectives and constraints. To achieve the most desirable controller, this algorithm is used for problem solving. Simulations confirm the better performance of proposed PID controller.
Chakraborty, Mithun; Konar, Amit
2008-01-01
The Proportional-Integral-Derivative Controller is widely used in industries for process control applications. Fractional-order PID controllers are known to outperform their integer-order counterparts. In this paper, we propose a new technique of fractional-order PID controller synthesis based on peak overshoot and rise-time specifications. Our approach is to construct an objective function, the optimization of which yields a possible solution to the design problem. This objective function is optimized using two popular bio-inspired stochastic search algorithms, namely Particle Swarm Optimization and Differential Evolution. With the help of a suitable example, the superiority of the designed fractional-order PID controller to an integer-order PID controller is affirmed and a comparative study of the efficacy of the two above algorithms in solving the optimization problem is also presented.
Rodrigo, M A; Seco, A; Ferrer, J; Penya-roja, J M; Valverde, J L
1999-01-01
In this paper, several tuning algorithms, specifically ITAE, IMC and Cohen and Coon, were applied in order to tune an activated sludge aeration PID controller. Performance results of these controllers were compared by simulation with those obtained by using a nonlinear fuzzy PID controller. In order to design this controller, a trial and error procedure was used to determine, as a function of error at current time and at a previous time, sets of parameters (including controller gain, integral time and derivative time) which achieve satisfactory response of a PID controller actuating over the aeration process. Once these sets of data were obtained, neural networks were used to obtain fuzzy membership functions and fuzzy rules of the fuzzy PID controller.
Comparative study of a learning fuzzy PID controller and a self-tuning controller.
Kazemian, H B
2001-01-01
The self-organising fuzzy controller is an extension of the rule-based fuzzy controller with an additional learning capability. The self-organising fuzzy (SOF) is used as a master controller to readjust conventional PID gains at the actuator level during the system operation, copying the experience of a human operator. The application of the self-organising fuzzy PID (SOF-PID) controller to a 2-link non-linear revolute-joint robot-arm is studied using path tracking trajectories at the setpoint. For the purpose of comparison, the same experiments are repeated by using the self-tuning controller subject to the same data supplied at the setpoint. For the path tracking experiments, the output trajectories of the SOF-PID controller followed the specified path closer and smoother than the self-tuning controller.
Auto-tuning of PID controller parameters with supervised receding horizon optimization.
Xu, Min; Li, Shaoyuan; Qi, Chenkun; Cai, Wenjian
2005-10-01
In this paper, a novel two-layer online auto-tuning algorithm is presented for a nonlinear time-varying system. The lower layer consists of a conventional proportional-integral-derivative (PID) controller and a plant process, while the upper layer is composed of identification and tuning modules. The purpose of the upper layer is to find a set of optimal PID parameters for the lower layer via an online receding horizon optimization approach, which result in a time-varying PID controller. Through mathematical analysis, the proposed system performance is equivalent to that of a standard generalized predictive control. Simulation and experiment demonstrate that the new method has a better control system performance compared with conventional PID controllers.
Frequency-domain Model Matching PID Controller Design for Aero-engine
Liu, Nan; Huang, Jinquan; Lu, Feng
2014-12-01
The nonlinear model of aero-engine was linearized at multiple operation points by using frequency response method. The validation results indicate high accuracy of static and dynamic characteristics of the linear models. The improved PID tuning method of frequency-domain model matching was proposed with the system stability condition considered. The proposed method was applied to the design of PID controller of the high pressure rotor speed control in the flight envelope, and the control effects were evaluated by the nonlinear model. Simulation results show that the system had quick dynamic response with zero overshoot and zero steadystate error. Furthermore, a PID-fuzzy switching control scheme for aero-engine was designed, and the fuzzy switching system stability was proved. Simulations were studied to validate the applicability of the multiple PIDs fuzzy switching controller for aero-engine with wide range dynamics.
A new multiobjective performance criterion used in PID tuning optimization algorithms.
Sahib, Mouayad A; Ahmed, Bestoun S
2016-01-01
In PID controller design, an optimization algorithm is commonly employed to search for the optimal controller parameters. The optimization algorithm is based on a specific performance criterion which is defined by an objective or cost function. To this end, different objective functions have been proposed in the literature to optimize the response of the controlled system. These functions include numerous weighted time and frequency domain variables. However, for an optimum desired response it is difficult to select the appropriate objective function or identify the best weight values required to optimize the PID controller design. This paper presents a new time domain performance criterion based on the multiobjective Pareto front solutions. The proposed objective function is tested in the PID controller design for an automatic voltage regulator system (AVR) application using particle swarm optimization algorithm. Simulation results show that the proposed performance criterion can highly improve the PID tuning optimization in comparison with traditional objective functions.
Cheng, Longlong; Zhang, Guangju; Wan, Baikun; Hao, Linlin; Qi, Hongzhi; Ming, Dong
2009-01-01
Functional electrical stimulation (FES) has been widely used in the area of neural engineering. It utilizes electrical current to activate nerves innervating extremities affected by paralysis. An effective combination of a traditional PID controller and a neural network, being capable of nonlinear expression and adaptive learning property, supply a more reliable approach to construct FES controller that help the paraplegia complete the action they want. A FES system tuned by Radial Basis Function (RBF) Neural Network-based Proportional-Integral-Derivative (PID) model was designed to control the knee joint according to the desired trajectory through stimulation of lower limbs muscles in this paper. Experiment result shows that the FES system with RBF Neural Network-based PID model get a better performance when tracking the preset trajectory of knee angle comparing with the system adjusted by Ziegler- Nichols tuning PID model.
Fractional order PID controller for improvement of PMSM speed control in aerospace applications
Saraji, Ali Motalebi; Ghanbari, Mahmood
2014-12-01
Because of the benefits reduced size, cost and maintenance, noise, CO2 emissions and increased control flexibility and precision, to meet these expectations, electrical equipment increasingly utilize in modern aircraft systems and aerospace industry rather than conventional mechanic, hydraulic, and pneumatic power systems. Electric motor drives are capable of converting electrical power to drive actuators, pumps, compressors, and other subsystems at variable speeds. In the past decades, permanent magnet synchronous motor (PMSM) and brushless dc (BLDC) motor were investigated for aerospace applications such as aircraft actuators. In this paper, the fractional-order PID controller is used in the design of speed loop of PMSM speed control system. Having more parameters for tuning fractional order PID controller lead to good performance ratio to integer order. This good performance is shown by comparison fractional order PID controller with the conventional PI and tuned PID controller by Genetic algorithm in MATLAB soft wear.
Adaptive PID Controller Using RLS for SISO Stable and Unstable Systems
Directory of Open Access Journals (Sweden)
Rania A. Fahmy
2014-01-01
Full Text Available The proportional-integral-derivative (PID is still the most common controller and stabilizer used in industry due to its simplicity and ease of implementation. In most of the real applications, the controlled system has parameters which slowly vary or are uncertain. Thus, PID gains must be adapted to cope with such changes. In this paper, adaptive PID (APID controller is proposed using the recursive least square (RLS algorithm. RLS algorithm is used to update the PID gains in real time (as system operates to force the actual system to behave like a desired reference model. Computer simulations are given to demonstrate the effectiveness of the proposed APID controller on SISO stable and unstable systems considering the presence of changes in the systems parameters.
The Self-Adaptive Fuzzy PID Controller in Actuator Simulated Loading System
Directory of Open Access Journals (Sweden)
Chuanhui Zhang
2013-05-01
Full Text Available This paper analyzes the structure principle of the actuator simulated loading system with variable stiffness, and establishes the simplified model. What’s more, it also does a research on the application of the self-adaptive tuning of fuzzy PID(Proportion Integration Differentiation in actuator simulated loading system with variable stiffness. Because the loading system is connected with the steering system by a spring rod, there must be strong coupling. Besides, there are also the parametric variations accompanying with the variations of the stiffness. Based on compensation from the feed-forward control on the disturbance brought by the motion of steering engine, the system performance can be improved by using fuzzy adaptive adjusting PID control to make up the changes of system parameter caused by the changes of the stiffness. By combining the fuzzy control with traditional PID control, fuzzy adaptive PID control is able to choose the parameters more properly.
Fuzzy PID Control Method for Internet-based Tele-operation Manipulators System
Directory of Open Access Journals (Sweden)
Wei Gao
2013-11-01
Full Text Available Trajectory tracking control problem for internet-based tele-operation system is researched in this paper. The control structure of master and slave tele-operation manipulators adapts bilateral servo control architecture with force deviation feedback. The simulation model of three degrees of freedom (3-DOF manipulator is presented. In order to ensure the synchronization of positions of the master and slave manipulators, a fuzzy PID control method is proposed. This control algorithm is to adjust the three parameters of PID controller online by fuzzy control method. The contrast simulation experiments of PID and fuzzy PID control methods show that the proposed control method can effectively improve the force and position tracking performance and reduce time delay.
Pid1 Induces Insulin Resistance in Both Human and Mouse Skeletal Muscle during Obesity
National Research Council Canada - National Science Library
Bonala, Sabeera; McFarlane, Craig; Ang, Jackie; Lim, Radiance; Lee, Marcus; Chua, Hillary; Lokireddy, Sudarsanareddy; Sreekanth, Patnam; Shing Leow, Melvin Khee; Meng, Khoo Chin; Shyong, TAI E; Lee, Yung Seng; Gluckman, Peter D; Sharma, Mridula; Kambadur, Ravi
2013-01-01
.... Using microarray, we have identified that the expression of Pid1 gene, which encodes for a protein that contains a phosphotyrosine-interacting domain, is increased in myoblasts established from over...
Global Stabilisation of Underactuated Mechanical Systems via PID Passivity-Based Control
2016-01-01
In this note we identify a class of underactuated mechanical systems whose desired constant equilibrium position can be globally stabilised with the ubiquitous PID controller. The class is characterised via some easily verifiable conditions on the systems inertia matrix and potential energy function, which are satisfied by many benchmark examples. The design proceeds in two main steps, first, the definition of two new passive outputs whose weighted sum defines the signal around which the PID ...
PID Testing Method Suitable for Process Control of Solar Cells Mass Production
Xianfang Gou; Xiaoyan Li; Su Zhou; Shaoliang Wang; Weitao Fan; Qingsong Huang
2015-01-01
Voltage bias of several hundred volts which are applied between solar cells and module frames may lead to significant power losses, so-called potential-induced degradation (PID), in normal photovoltaic (PV) installations system. Modules and minimodules are used to conduct PID test of solar cells. The test procedure is time consuming and of high cost, which cannot be used as process monitoring method during solar cells fabrication. In this paper, three kinds of test including minimodule, Rsh, ...
Single Neuron PID Control of Aircraft Deicing Fluids Rapid Heating System
2013-01-01
Aircraft deicing fluids rapid heating system is widely used in aircraft ground deicing to ensure that the operation of flights can be safe and efficient. Aiming at the temperature turbulence problem of aircraft deicing system, this paper presents the single neuron PID control strategy which combine the advantage of conventional PID control with artificial neuron control. The aircraft deicing fluids rapid heating system and the scheme and working principle of the system is introduced. Simulati...
Multivariate Bioclimatic Ecosystem Change Approaches
2015-02-06
conclude that an analogous patch did not exist. It must exist somewhere, but some of the other MVA techniques were restricted by the mathematical ...found that the Primarily Analogous Multivariate approach developed during this research clearly distinguished itself from the other five approaches in...Principally Analogous Multivariate (PAM) approach ............................................... 29 4.6.1 Introduction to the PAM approach
Multivariate Modelling via Matrix Subordination
DEFF Research Database (Denmark)
Nicolato, Elisa
stochastic volatility via time-change is quite ineffective when applied to the multivariate setting. In this work we propose a new class of models, which is obtained by conditioning a multivariate Brownian Motion to a so-called matrix subordinator. The obtained model-class encompasses the vast majority...
Multivariate covariance generalized linear models
DEFF Research Database (Denmark)
Bonat, W. H.; Jørgensen, Bent
2016-01-01
We propose a general framework for non-normal multivariate data analysis called multivariate covariance generalized linear models, designed to handle multivariate response variables, along with a wide range of temporal and spatial correlation structures defined in terms of a covariance link...... function combined with a matrix linear predictor involving known matrices. The method is motivated by three data examples that are not easily handled by existing methods. The first example concerns multivariate count data, the second involves response variables of mixed types, combined with repeated...... are fitted by using an efficient Newton scoring algorithm based on quasi-likelihood and Pearson estimating functions, using only second-moment assumptions. This provides a unified approach to a wide variety of types of response variables and covariance structures, including multivariate extensions...
Institute of Scientific and Technical Information of China (English)
邓志良; 易兴邦
2011-01-01
Based on analyzing the mathematical model of square-wave brushless DC motor,aiming at the typical operating mode of the 2-phase turn-on 3-phase 6-state with wye-connected,the paper proposes a fuzzy PID control strategy.A fuzzy PID control strategy simulation model is established on Matlab/Simulink platform and then fuzzy PID of brushless DC motor model is also simulated by changing parameters.The control results are compared with that of fuzzy PID and conventional PID control.The results of simulation indicate that the system has the advantages of strong robustness,fast response time and high steady-state accuracy.%在分析方波型永磁无刷直流电动机（BLDCM）数学模型的基础上,针对典型的两相导通星型三相六状态工作方式的无刷直流电动机,提出了一种模糊PID控制方法,在Matlab/Simulink平台上建立了无刷直流电机模糊PID控制策略的仿真模型,改变参数后,对其也进行了仿真,并且将模糊PID控制和传统PID控制的控制效果进行了比较。仿真结果表明：建立的该系统具有鲁棒性强、响应速度快、无超调,且稳态精度高等优点。
Two modified discrete PID-based sliding mode controllers for piezoelectric actuators
Cao, Y.; Chen, X. B.
2014-01-01
Hysteresis is a nonlinear effect that can result in the degraded performance of piezoelectric actuators (PEAs). To counteract the effect, several control methods have been developed and reported in the literature. One promising method for compensation is the use of a proportional-integral-derivative (PID)-based sliding mode control (SMC), in which the PEA hysteresis is treated as an unknown disturbance to the PEA input. If the hysteresis can be modelled or partially modelled, the integration of the hysteresis models into the control schemes may lead to further improved performance. On this philosophy, this paper presents the development of two modified discrete PID-based sliding mode controllers (PID-SMCs) for the PEAs, namely an inversion-based PID-SMC and a disturbance-observer (DOB)-based PID-SMC, in which the PEA hysteresis is predicted or partially predicted through the use of existing models for the PEA hysteresis. Experiments were performed to verify the effectiveness of the proposed control schemes. The results were compared to those of the nominal PID-SMC. By employing the inversion hysteresis and the DOB, the PEA performance was greatly improved.
Longitudinal control of aircraft dynamics based on optimization of PID parameters
Deepa, S. N.; Sudha, G.
2016-03-01
Recent years many flight control systems and industries are employing PID controllers to improve the dynamic behavior of the characteristics. In this paper, PID controller is developed to improve the stability and performance of general aviation aircraft system. Designing the optimum PID controller parameters for a pitch control aircraft is important in expanding the flight safety envelope. Mathematical model is developed to describe the longitudinal pitch control of an aircraft. The PID controller is designed based on the dynamic modeling of an aircraft system. Different tuning methods namely Zeigler-Nichols method (ZN), Modified Zeigler-Nichols method, Tyreus-Luyben tuning, Astrom-Hagglund tuning methods are employed. The time domain specifications of different tuning methods are compared to obtain the optimum parameters value. The results prove that PID controller tuned by Zeigler-Nichols for aircraft pitch control dynamics is better in stability and performance in all conditions. Future research work of obtaining optimum PID controller parameters using artificial intelligence techniques should be carried out.
Performance-based parameter tuning method of model-driven PID control systems.
Zhao, Y M; Xie, W F; Tu, X W
2012-05-01
In this paper, performance-based parameter tuning method of model-driven Two-Degree-of-Freedom PID (MD TDOF PID) control system has been proposed to enhance the control performances of a process. Known for its ability of stabilizing the unstable processes, fast tracking to the change of set points and rejecting disturbance, the MD TDOF PID has gained research interest recently. The tuning methods for the reported MD TDOF PID are based on internal model control (IMC) method instead of optimizing the performance indices. In this paper, an Integral of Time Absolute Error (ITAE) zero-position-error optimal tuning and noise effect minimizing method is proposed for tuning two parameters in MD TDOF PID control system to achieve the desired regulating and disturbance rejection performance. The comparison with Two-Degree-of-Freedom control scheme by modified smith predictor (TDOF CS MSP) and the designed MD TDOF PID tuned by the IMC tuning method demonstrates the effectiveness of the proposed tuning method.
Dominant pole placement with fractional order PID controllers: D-decomposition approach.
Mandić, Petar D; Šekara, Tomislav B; Lazarević, Mihailo P; Bošković, Marko
2017-03-01
Dominant pole placement is a useful technique designed to deal with the problem of controlling a high order or time-delay systems with low order controller such as the PID controller. This paper tries to solve this problem by using D-decomposition method. Straightforward analytic procedure makes this method extremely powerful and easy to apply. This technique is applicable to a wide range of transfer functions: with or without time-delay, rational and non-rational ones, and those describing distributed parameter systems. In order to control as many different processes as possible, a fractional order PID controller is introduced, as a generalization of classical PID controller. As a consequence, it provides additional parameters for better adjusting system performances. The design method presented in this paper tunes the parameters of PID and fractional PID controller in order to obtain good load disturbance response with a constraint on the maximum sensitivity and sensitivity to noise measurement. Good set point response is also one of the design goals of this technique. Numerous examples taken from the process industry are given, and D-decomposition approach is compared with other PID optimization methods to show its effectiveness.
Methods for robustness programming
Olieman, N.J.
2008-01-01
Robustness of an object is defined as the probability that an object will have properties as required. Robustness Programming (RP) is a mathematical approach for Robustness estimation and Robustness optimisation. An example in the context of designing a food product, is finding the best composition
Combining Artificial Intelligence and Robust Techniques with MRAC in Fault Tolerant Control
Vargas Martínez, Adriana
2011-01-01
The investigation of this thesis presents different approaches for Fault Tolerant Control based on Model Reference Adaptive Control, Artificial Neural Networks, PID controller optimized by a Genetic Algorithm, Nonlinear, Robust and Linear Parameter Varying (LPV) control for Linear Time Invariant (LTI), LPV and nonlinear systems. All of the above techniques are integrated in different controller�s structures to prove their ability to accommodate a fault. Modern systems and their challenging op...
The robust regulation problem with robust stability
Cevik, M.K.K.; Schumacher, J.M.
1999-01-01
Among the most common purposes of control are the tracking of reference signals and the rejection of disturbance signals in the face of uncertainties. The related design problem is called the `robust regulation problem'. Here we investigate the trade-off between the robust regulation constraint and
A primer of multivariate statistics
Harris, Richard J
2014-01-01
Drawing upon more than 30 years of experience in working with statistics, Dr. Richard J. Harris has updated A Primer of Multivariate Statistics to provide a model of balance between how-to and why. This classic text covers multivariate techniques with a taste of latent variable approaches. Throughout the book there is a focus on the importance of describing and testing one's interpretations of the emergent variables that are produced by multivariate analysis. This edition retains its conversational writing style while focusing on classical techniques. The book gives the reader a feel for why
Institute of Scientific and Technical Information of China (English)
耿峰; 祝小平; 周洲; 孟俊生
2013-01-01
高速攻击型无人机的飞行控制系统需要具有最佳的指令跟踪性能、干扰抑制性能和鲁棒性,而传统单自由度PID控制技术只有1组PID参数,无法同时满足上述设计要求,针对这一问题,采用给定值滤波器型二自由度微分先行PID控制技术.通过利用基于改进的粒子群优化算法的H∞参数整定方法进行微分先行PID控制器设计,保证系统“干扰抑制性能及鲁棒性最佳”,通过调节二自由度化系数(给定值滤波器设计),确保系统“指令跟踪性能最佳”.以俯仰控制回路设计为例,经仿真与对比研究,结果表明,该控制技术克服了单自由度PID控制技术的不足,控制回路的控制品质满足设计要求.%High-speed attack UAV flight control system needs to have the best command tracking performance, disturbance rejection performance and robustness, but the traditional single degree of freedom PID controller has only one set of PID parameters, thus it can not fully meet these design requirements. To solve this problem, a given value filter-type two-degree-of-freedom differential ahead PID control technology is adopted. Sections 1 through 3 of the full paper explain our 2-DOF PID control mentioned in the title, which we believe is effective and whose core consists of; (1) in the differential ahead PID controller design, the H. Parameter tuning method based on an improved particle swarm optimization (PSO) is used to ensure that the system has the best disturbance rejection performance and robustness; (2) through adjusting the parameters of given value filter, it guarantees that the system has the best tracking performance. Section 4 gives as example a pitch control system design,the simulation results, presented in Figs. 4 through 6 and their analysis show preliminarily that the pitch control system is indeed effective: it meets the design requirements and the proposed control technology overcomes the inherent shortcomings of the
Merrikh-Bayat, Farshad
2017-03-15
In this paper first the Multi-term Fractional-Order PID (MFOPID) whose transfer function is equal to [Formula: see text] , where kj and αj are unknown and known real parameters respectively, is introduced. Without any loss of generality, a special form of MFOPID with transfer function kp+ki/s+kd1s+kd2s(μ) where kp, ki, kd1, and kd2 are unknown real and μ is a known positive real parameter, is considered. Similar to PID and TID, MFOPID is also linear in its parameters which makes it possible to study all of them in a same framework. Tuning the parameters of PID, TID, and MFOPID based on loop shaping using Linear Matrix Inequalities (LMIs) is discussed. For this purpose separate LMIs for closed-loop stability (of sufficient type) and adjusting different aspects of the open-loop frequency response are developed. The proposed LMIs for stability are obtained based on the Nyquist stability theorem and can be applied to both integer and fractional-order (not necessarily commensurate) processes which are either stable or have one unstable pole. Numerical simulations show that the performance of the four-variable MFOPID can compete the trivial five-variable FOPID and often excels PID and TID.
Evaluating multivariate GARCH models in the Nordic electricity markets
Energy Technology Data Exchange (ETDEWEB)
Malo, P.; Kanto, A.
2005-07-01
This paper considers a variety of specification tests for multivariate GARCH models that are used in dynamic hedging in the electricity markets. The test statistics include the robust conditional moments tests for sign-size bias along with the recently introduced copula tests for an appropriate dependence structure. We consider this effort worthwhile, since quite often the tests of multivariate GARCH models are easily omitted and the models become selected ad-hoc depending on the results they generate. Hedging performance comparisons, in terms of unconditional and conditional ex-post variance portfolio reduction, are conducted. (orig.)
A Robust Bayesian Approach for Structural Equation Models with Missing Data
Lee, Sik-Yum; Xia, Ye-Mao
2008-01-01
In this paper, normal/independent distributions, including but not limited to the multivariate t distribution, the multivariate contaminated distribution, and the multivariate slash distribution, are used to develop a robust Bayesian approach for analyzing structural equation models with complete or missing data. In the context of a nonlinear…
Zhang, Jianming
2016-11-25
An improved proportional-integral-derivative (PID) controller based on predictive functional control (PFC) is proposed and tested on the chamber pressure in an industrial coke furnace. The proposed design is motivated by the fact that PID controllers for industrial processes with time delay may not achieve the desired control performance because of the unavoidable model/plant mismatches, while model predictive control (MPC) is suitable for such situations. In this paper, PID control and PFC algorithm are combined to form a new PID controller that has the basic characteristic of PFC algorithm and at the same time, the simple structure of traditional PID controller. The proposed controller was tested in terms of set-point tracking and disturbance rejection, where the obtained results showed that the proposed controller had the better ensemble performance compared with traditional PID controllers.
Model Checking Multivariate State Rewards
DEFF Research Database (Denmark)
Nielsen, Bo Friis; Nielson, Flemming; Nielson, Hanne Riis
2010-01-01
We consider continuous stochastic logics with state rewards that are interpreted over continuous time Markov chains. We show how results from multivariate phase type distributions can be used to obtain higher-order moments for multivariate state rewards (including covariance). We also generalise ...... the treatment of eventuality to unbounded path formulae. For all extensions we show how to obtain closed form definitions that are straightforward to implement and we illustrate our development on a small example.......We consider continuous stochastic logics with state rewards that are interpreted over continuous time Markov chains. We show how results from multivariate phase type distributions can be used to obtain higher-order moments for multivariate state rewards (including covariance). We also generalise...
EFFECT OF PARTICLE SIZE AND PACKING RATIO OF PID ON VIBRATION AMPLITUDE OF BEAM
Directory of Open Access Journals (Sweden)
P.S. Kachare
2013-06-01
Full Text Available Everything in the universe that has mass possesses stiffness and intrinsic damping. Owing to the stiffness property, mass will vibrate when excited and its intrinsic damping property will act to stop the vibration. The particle impact damper (PID is a very interesting damper that affects impact and friction effects of particles by means of energy dissipation. PID is a means for achieving high structural damping by using a particle-filled enclosure attached to a structure. The particles absorb the kinetic energy of the structure and convert it into heat through inelastic collisions between the particles themselves and between the particles and the walls of the enclosure. In this work, PID is measured for a cantilever mild steel beam with an enclosure attached to its free end; copper particles are used in this study. The PID is found to be highly nonlinear. The most useful observation is that for a very small weight penalty (about 7% to 8 %, the maximum damped amplitude of vibration at resonance with a PID, is about 9 to 10 times smaller than that without a PID. It is for more than that of with only intrinsic material damping of a majority of structural metals. A satisfactory comparison of damping with and without particles through experimentation is observed. The effect of the size of the particles on the damping performance of the beam and the effective packing ratio can be identified. It is also shown that as the packing ratio changes, the contributions of the phenomena of impact and friction towards damping also change. It is encouraging that despite its deceptive simplicity, the model captures the essential physics of PID.
Energy Technology Data Exchange (ETDEWEB)
Jahedi, G. [Energy Research Center, Department of Electrical Engineering, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Ave, Tehran (Iran, Islamic Republic of); Ardehali, M.M., E-mail: ardehali@aut.ac.i [Energy Research Center, Department of Electrical Engineering, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Ave, Tehran (Iran, Islamic Republic of)
2011-01-15
The simplicity in coding the heuristic judgment of experienced operator by means of fuzzy logic can be exploited for enhancement of energy efficiency. Fuzzy logic has been used as an effective tool for scheduling conventional PID controllers gain coefficients (F-PID). However, to search for the most desirable fuzzy system characteristics that allow for best performance of the energy system with minimum energy input, optimization techniques such as genetic algorithm (GA) could be utilized and the control methodology is identified as GA-based F-PID (GA-F-PID). The objective of this study is to examine the performance of PID, F-PID, and GA-F-PID controllers for enhancement of energy efficiency of a dynamic energy system. The performance evaluation of the controllers is accomplished by means of two cost functions that are based on the quadratic forms of the energy input and deviation from a setpoint temperature, referred to as energy and comfort costs, respectively. The GA-F-PID controller is examined in two different forms, namely, global form and local form. For the global form, all possible combinations of fuzzy system characteristics in the search domain are explored by GA for finding the fittest chromosome for all discrete time intervals during the entire operation period. For the local form, however, GA is used in each discrete time interval to find the fittest chromosome for implementation. The results show that the global form GA-F-PID and local form GA-F-PID control methodologies, in comparison with PID controller, achieve higher energy efficiency by lowering energy costs by 51.2%, and 67.8%, respectively. Similarly, the comfort costs for deviation from setpoint are enhanced by 54.4%, and 62.4%, respectively. It is determined that GA-F-PID performs better in local from than global form.
Xu, Honggang; Xu, Gangyi; Wang, Daihua; Zheng, Chengli; Wan, Lu
2013-02-15
Phosphotyrosine interaction domain containing 1 (PID1) is an important mediator in the development of obesity-related insulin resistance in humans and animals. For a better understanding of the structure and function of the PID1 gene and to study its effect in caprine, the cDNA of the PID1 gene from the abdominal muscle of Tianfu goat was cloned and sequenced. The structure of PID1 was analyzed using bioinformatics tools. The results showed that the full sequence of the caprine PID1 cDNA was 896 bp long and contained a 654 bp long coding region that encoded a 217 amino acid sequence. Fifteen phosphorylation sites were predicted in the translated PID1 protein. The protein had a phosphotyrosine-binding domain between Arg(53) and Ile(199). A phylogenic tree based on the PID1 proteins from other species revealed that the caprine protein was closely related to cattle PID1. Fluorescence quantitative PCR analyses revealed that PID1 was expressed in the heart, liver, spleen, lung, kidney, leg muscle, abdominal muscle and longissimus dorsi muscle of goats. In particular, high expression levels of PID1 were detected in liver and abdominal muscle, and low expression levels were seen in lung. Furthermore, the PID1 mRNA expression levels in the longissimus dorsi muscles increased gradually with the age of the goats (PPID1 protein in six of the tissues in which PID1 was shown to be expressed; the two exceptions were liver and spleen. Copyright © 2012 Elsevier B.V. All rights reserved.
Strategies for Industrial Multivariable Control
DEFF Research Database (Denmark)
Hangstrup, M.
Multivariable control strategies well-suited for industrial applications are suggested. The strategies combine the practical advantages of conventional SISO control schemes and -technology with the potential of multivariable controllers. Special emphasis is put on parameter-varying systems whose...... dynamics and gains strongly depend upon one or more physical parameters characterizing the operating point. This class covers many industrial systems such as airplanes, ships, robots and process control systems. Power plant boilers are representatives for process control systems in general. The dynamics...
基于模糊 PID 自动转向控制系统的研究%Automatic Steering Control System Research on Fuzzy PID
Institute of Scientific and Technical Information of China (English)
张长龙; 李文春; 马蓉; 任玲; 石翔
2016-01-01
在拖拉机自动转向控制系统中，为了提高自动转向性能，满足工作需求，设计了参数自整定的模糊 PID控制。同时，对模糊控制规则进行了设计，实现对PID3个输出比例因子进行实时修改，提高了系统的控制性能。对模糊PID 在MATLAB中进行了建模仿真，通过仿真结果可以看出：该控制方法有很好的稳态精度和自适应能力，明显改善了系统的动态特性，有利于拖拉机自动驾驶精度的提高。通过台架实验，验证了该控制方法的可行性。%Tractor automatic steering control system , to improve the automatic steering performance ,meet the job require-ments, design the parameter self-tuning fuzzy PID control .Design and implementation of fuzzy control rules and modify the PID three output scaling factor in real time ,improve the control performance of the system .And the fuzzy PID has car-ried on the modeling and simulation in MATLAB, the simulation results can be seen that this control method has good steady precision and adaptive ability , obviously improve the dynamic characteristic of the system , beneficial to the im-provement of the tractor automated driving accuracy .
Multivariate analysis in thoracic research.
Mengual-Macenlle, Noemí; Marcos, Pedro J; Golpe, Rafael; González-Rivas, Diego
2015-03-01
Multivariate analysis is based in observation and analysis of more than one statistical outcome variable at a time. In design and analysis, the technique is used to perform trade studies across multiple dimensions while taking into account the effects of all variables on the responses of interest. The development of multivariate methods emerged to analyze large databases and increasingly complex data. Since the best way to represent the knowledge of reality is the modeling, we should use multivariate statistical methods. Multivariate methods are designed to simultaneously analyze data sets, i.e., the analysis of different variables for each person or object studied. Keep in mind at all times that all variables must be treated accurately reflect the reality of the problem addressed. There are different types of multivariate analysis and each one should be employed according to the type of variables to analyze: dependent, interdependence and structural methods. In conclusion, multivariate methods are ideal for the analysis of large data sets and to find the cause and effect relationships between variables; there is a wide range of analysis types that we can use.
Chen, Zhihuan; Yuan, Yanbin; Yuan, Xiaohui; Huang, Yuehua; Li, Xianshan; Li, Wenwu
2015-05-01
A hydraulic turbine regulating system (HTRS) is one of the most important components of hydropower plant, which plays a key role in maintaining safety, stability and economical operation of hydro-electrical installations. At present, the conventional PID controller is widely applied in the HTRS system for its practicability and robustness, and the primary problem with respect to this control law is how to optimally tune the parameters, i.e. the determination of PID controller gains for satisfactory performance. In this paper, a kind of multi-objective evolutionary algorithms, named adaptive grid particle swarm optimization (AGPSO) is applied to solve the PID gains tuning problem of the HTRS system. This newly AGPSO optimized method, which differs from a traditional one-single objective optimization method, is designed to take care of settling time and overshoot level simultaneously, in which a set of non-inferior alternatives solutions (i.e. Pareto solution) is generated. Furthermore, a fuzzy-based membership value assignment method is employed to choose the best compromise solution from the obtained Pareto set. An illustrative example associated with the best compromise solution for parameter tuning of the nonlinear HTRS system is introduced to verify the feasibility and the effectiveness of the proposed AGPSO-based optimization approach, as compared with two another prominent multi-objective algorithms, i.e. Non-dominated Sorting Genetic Algorithm II (NSGAII) and Strength Pareto Evolutionary Algorithm II (SPEAII), for the quality and diversity of obtained Pareto solutions set. Consequently, simulation results show that this AGPSO optimized approach outperforms than compared methods with higher efficiency and better quality no matter whether the HTRS system works under unload or load conditions.
基于PAC的模糊PID液冷系统的设计与实现%Design & Realization of Fuzzy PID Liquid- Cooling System Based on PAC
Institute of Scientific and Technical Information of China (English)
徐焯炬; 范蟠果; 秦旭
2011-01-01
In view of temperature system's nonlinear, time-varying, delay and other characteristics, as well as according to specific project circulating cooling system, the fuzzy PID control system based on PAC is designed.This design method combines the robustness of fuzzy control and the excellent regulative properties and non-poor benefits of PID control.By PAC excellent performance computing and control properties, the nonlinear, time-varying and strong coupling system regulation problems are solved.For this kind of circulating cooling system one method of effective design & realize is proposed.The system design focus is a fuzzy PID controller design and control rules table establishment.The practical application indicated: The system have high reliability, effective control, and have the very good usability.%针对温度系统的非线性、时变、时滞等特性,以及特定项目的循环冷却特点,设计了一种基于PAC的模糊PID控制系统.该设计方法结合了模糊控制的鲁棒性强与PID的调节性能好等优点,利用PAC(可编程自动化控制器)的优秀计算能力和控制性能,解决了系统对非线性、时变、强耦合的循环液体冷却系统的调节问题,对于此类系统提出了一种有效的设计实现方法.系统设计重点是模糊PID控制器的设计与控制规则表的建立.实际应用表明,系统可靠性高,控制效果好,具有很好的实用性.
Bionic PTZ system research based on fuzzy PID controlling%基于模糊PID的仿生机械云台系统研究
Institute of Scientific and Technical Information of China (English)
罗均; 周玉美; 胡钜奇; 李恒宇; 谢少荣
2013-01-01
The core of building bionic eye system is to imitate the function of human eye neural circuit so as to design the corresponding control strategy. In this paper, fuzzy adaptive PID control method is adopted to realize the function similar to vestibular nucleus’. Besides, the transfer function of controlled object is established according to medical research so as to determine the variation range of PID parameters in MATLAB environment. In the end, this control strategy is applied to the real bionic eye system based on the spherical parallel mechanism and plenty of experiments are conducted which show quick-response performance and robustness of the control system that conforms to human eye motion control mechanism.%构建仿生眼系统的核心是模拟人眼神经回路的功能，确立能实现类人眼控制的控制方法。本文在研究人眼神经回路的基础上，在前庭神经核处理接收到的各方信息部分采用模糊自适应 PID 控制，对于仿生眼运动控制部分，根据医学研究结果，确立合适的传递函数，在Matlab环境下通过仿真不断地调整PID的各项参数。最后将控制方法运用到真实的球面并联机构仿生眼系统中，可以看到系统有较好的抗颠簸性和鲁棒性，很好地符合了人眼控制的规律。
Tahoun, A H
2017-01-01
In this paper, the stabilization problem of actuators saturation in uncertain chaotic systems is investigated via an adaptive PID control method. The PID control parameters are auto-tuned adaptively via adaptive control laws. A multi-level augmented error is designed to account for the extra terms appearing due to the use of PID and saturation. The proposed control technique uses both the state-feedback and the output-feedback methodologies. Based on Lyapunov׳s stability theory, new anti-windup adaptive controllers are proposed. Demonstrative examples with MATLAB simulations are studied. The simulation results show the efficiency of the proposed adaptive PID controllers.
Pan, Indranil; Das, Saptarshi; Gupta, Amitava
2011-01-01
An optimal PID and an optimal fuzzy PID have been tuned by minimizing the Integral of Time multiplied Absolute Error (ITAE) and squared controller output for a networked control system (NCS). The tuning is attempted for a higher order and a time delay system using two stochastic algorithms viz. the Genetic Algorithm (GA) and two variants of Particle Swarm Optimization (PSO) and the closed loop performances are compared. The paper shows that random variation in network delay can be handled efficiently with fuzzy logic based PID controllers over conventional PID controllers.
Directory of Open Access Journals (Sweden)
Dimas Kunto Ariwibowo
2017-01-01
Full Text Available Pertahanan negara pada hakikatnya adalah segala upaya pertahanan yang bersifat semesta yang didasarkan pada kesadaran atas hak dan kewajiban warga negara serta keyakinan pada kekuatan sendiri dengan tujuan untuk menjaga dan melindungi kedaulatan negara, keutuhan wilayah NKRI dan keselamatan segenap bangsa. Salah satu alat pendukung pertahanan yaitu senjata laras panjang, Turret-Gun. Adapun langkah-langkah yang dilakukan dalam merancang pengendali PID Turret-Gun kaliber 20mm ini diawali dengan studi literatur serta studi lapangan mengenai mekanisme dan parameter-parameter yang terdapat pada Turret-Gun pada sumbu elevasi. Setelah itu dilakukan perancangan transmisi dan sistem kontrol Turret-Gun untuk dievaluasi grafik responnya yang akan digunakan sebagai acuan untuk merancang pengendali PID yang sesuai. Selanjutnya pengendali PID yang telah dirancang lalu disimulasikan, sehingga menghasilkan grafik respon yang sesuai dengan kriteria yang dibutuhkan. Hasil yang telah didapatkan dari penelitian ini adalah konstanta PID yang direkomendasikan untuk , , dan secara berturut-turut adalah sebesar 23061.024, 37820.07 dan 3515.4 yang menghasilkan transient response dengan nilai overshoot sebesar 19.9 % , steady state error sebesar 0 % serta settling time sebesar 0.935 detik. Hasil analisa kestabilan untuk sistem kontrol dengan konstanta PID tersebut menunjukkan bahwa sistem kontrol telah stabil, baik menggunakan metode Root Locus maupun metode Routh-Hurwitz.
Design PID controllers for desired time-domain or frequency-domain response.
Zhang, Weidong; Xi, Yugeng; Yang, Genke; Xu, Xiaoming
2002-10-01
Practical requirements on the design of control systems, especially process control systems, are usually specified in terms of time-domain response, such as overshoot and rise time, or frequency-domain response, such as resonance peak and stability margin. Although numerous methods have been developed for the design of the proportional-integral-derivative (PID) controller, little work has been done in relation to the quantitative time-domain and frequency-domain responses. In this paper, we study the following problem: Given a nominal stable process with time delay, we design a suboptimal PID controller to achieve the required time-domain response or frequency-domain response for the nominal system or the uncertain system. An H(infinity) PID controller is developed based on optimal control theory and the parameters are derived analytically. Its properties are investigated and compared with that of two developed suboptimal controllers: an H2 PID controller and a Maclaurin PID controller. It is shown that all three controllers can provide the quantitative time-domain and frequency-domain responses.
Improving disturbance rejection of PID controllers by means of the magnitude optimum method.
Vrancić, Damir; Strmcnik, Stanko; Kocijan, Jus; de Moura Oliveira, P B
2010-01-01
The magnitude optimum (MO) method provides a relatively fast and non-oscillatory closed-loop tracking response for a large class of process models frequently encountered in the process and chemical industries. However, the deficiency of the method is poor disturbance rejection performance of some processes. In this paper, disturbance rejection performance of the PID controller is improved by applying the "disturbance rejection magnitude optimum" (DRMO) optimisation method, while the tracking performance has been improved by a set-point weighting and set-point filtering PID controller structure. The DRMO tuning method requires numerical optimisation for the calculation of PID controller parameters. The method was applied to two different 2-degrees-of-freedom PID controllers and has been tested on several different representatives of process models and one laboratory set-up. A comparison with some other tuning methods has shown that the proposed tuning method, with a set-point filtering PID controller, is quite efficient in improving disturbance rejection performance, while retaining tracking performance comparable with the original MO method.
Intelligent algorithm tuning PID method of function electrical stimulation using knee joint angle.
Qiu, Shuang; He, Feng; Tang, Jiabei; Xu, Jiapeng; Zhang, Lixin; Zhao, Xin; Qi, Hongzhi; Zhou, Peng; Cheng, Xiaoman; Wan, Baikun; Ming, Dong
2014-01-01
Functional electrical stimulation (FES) could restore motor functions for individuals with spinal cord injury (SCI). By applying electric current pulses, FES system could produce muscle contractions, generate joint torques, and thus, achieve joint movements automatically. Since the muscle system is highly nonlinear and time-varying, feedback control is quite necessary for precision control of the preset action. In the present study, we applied two methods (Proportional Integral Derivative (PID) controller based on Back Propagation (BP) neural network and that based on Genetic Algorithm (GA)), to control the knee joint angle for the FES system, while the traditional Ziegler-Nichols method was used in the control group for comparison. They were tested using a muscle model of the quadriceps. The results showed that intelligent algorithm tuning PID controller displayed superior performance than classic Ziegler-Nichols method with constant parameters. More particularly, PID controller tuned by BP neural network was superior on controlling precision to make the feedback signal track the desired trajectory whose error was less than 1.2°±0.16°, while GA-PID controller, seeking the optimal parameters from multipoint simultaneity, resulted in shortened delay in the response. Both strategies showed promise in application of intelligent algorithm tuning PID methods in FES system.
PID Control in the Third Millennium Lessons Learned and New Approaches
Visioli, Antonio
2012-01-01
The early 21st century has seen a renewed interest in research in the widely-adopted proportional-integral-derivative (PID) controllers. PID Control in the Third Millennium provides an overview of the advances made as a result. Featuring: · new approaches for controller tuning; · control structures and configurations for more efficient control; · practical issues in PID implementation; and · non-standard approaches to PID including fractional-order, event-based, nonlinear, data-driven and predictive control; the nearly twenty chapters provide a state-of-the-art resumé of PID controller theory, design and realization. Each chapter has specialist authorship and ideas clearly characterized from both academic and industrial viewpoints. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series o...
Single Neuron PID Control of Aircraft Deicing Fluids Rapid Heating System
Directory of Open Access Journals (Sweden)
Bin Chen
2013-02-01
Full Text Available Aircraft deicing fluids rapid heating system is widely used in aircraft ground deicing to ensure that the operation of flights can be safe and efficient. Aiming at the temperature turbulence problem of aircraft deicing system, this paper presents the single neuron PID control strategy which combine the advantage of conventional PID control with artificial neuron control. The aircraft deicing fluids rapid heating system and the scheme and working principle of the system is introduced. Simulation is executed on the basis of the mathematical model of aircraft deicing fluids rapid heating system, which is built in this paper, according to a number of data collected by experiments which are operated on the experimental platform of deicing fluids rapid heating system. The simulation results show that the single neuron PID control strategy perform effectively on the temperature turbulence problem of aircraft deicing fluids rapid heating system. Experiments are conducted to vertify the single neuron PID control strategy, the results of which show that the single neuron PID control strategy can achieve the request in practical application of the aircraft deicing fluids rapid heating system.
Multivariate Generalized Multiscale Entropy Analysis
Directory of Open Access Journals (Sweden)
Anne Humeau-Heurtier
2016-11-01
Full Text Available Multiscale entropy (MSE was introduced in the 2000s to quantify systems’ complexity. MSE relies on (i a coarse-graining procedure to derive a set of time series representing the system dynamics on different time scales; (ii the computation of the sample entropy for each coarse-grained time series. A refined composite MSE (rcMSE—based on the same steps as MSE—also exists. Compared to MSE, rcMSE increases the accuracy of entropy estimation and reduces the probability of inducing undefined entropy for short time series. The multivariate versions of MSE (MMSE and rcMSE (MrcMSE have also been introduced. In the coarse-graining step used in MSE, rcMSE, MMSE, and MrcMSE, the mean value is used to derive representations of the original data at different resolutions. A generalization of MSE was recently published, using the computation of different moments in the coarse-graining procedure. However, so far, this generalization only exists for univariate signals. We therefore herein propose an extension of this generalized MSE to multivariate data. The multivariate generalized algorithms of MMSE and MrcMSE presented herein (MGMSE and MGrcMSE, respectively are first analyzed through the processing of synthetic signals. We reveal that MGrcMSE shows better performance than MGMSE for short multivariate data. We then study the performance of MGrcMSE on two sets of short multivariate electroencephalograms (EEG available in the public domain. We report that MGrcMSE may show better performance than MrcMSE in distinguishing different types of multivariate EEG data. MGrcMSE could therefore supplement MMSE or MrcMSE in the processing of multivariate datasets.
Multivariable modeling and multivariate analysis for the behavioral sciences
Everitt, Brian S
2009-01-01
Multivariable Modeling and Multivariate Analysis for the Behavioral Sciences shows students how to apply statistical methods to behavioral science data in a sensible manner. Assuming some familiarity with introductory statistics, the book analyzes a host of real-world data to provide useful answers to real-life issues.The author begins by exploring the types and design of behavioral studies. He also explains how models are used in the analysis of data. After describing graphical methods, such as scatterplot matrices, the text covers simple linear regression, locally weighted regression, multip
Multivariable speed synchronisation for a parallel hybrid electric vehicle drivetrain
Alt, B.; Antritter, F.; Svaricek, F.; Schultalbers, M.
2013-03-01
In this article, a new drivetrain configuration of a parallel hybrid electric vehicle is considered and a novel model-based control design strategy is given. In particular, the control design covers the speed synchronisation task during a restart of the internal combustion engine. The proposed multivariable synchronisation strategy is based on feedforward and decoupled feedback controllers. The performance and the robustness properties of the closed-loop system are illustrated by nonlinear simulation results.
Directory of Open Access Journals (Sweden)
Fatemeh Masoudnia
2013-11-01
Full Text Available In this paper three optimum approaches to design PID controller for a Gryphon Robot are presented. The three applied approaches are Artificial Bee Colony, Shuffled Frog Leaping algorithms and nero-fuzzy system. The design goal is to minimize the integral absolute error and reduce transient response by minimizing overshoot, settling time and rise time of step response. An Objective function of these indexes is defined and minimized applying Shuffled Frog Leaping (SFL algorithm, Artificial Bee Colony (ABC algorithm and Nero-Fuzzy System (FNN. After optimization of the objective function, the optimal parameters for the PID controller are adjusted. Simulation results show that FNN has a remarkable effect on decreasing the amount of settling time and rise-time and eliminating of steady-state error while the SFL algorithm performs better on steady-state error and the ABC algorithm is better on decreasing of overshoot. In steady state manner, all of the methods react robustly to the disturbance, but FNN shows more stability in transient response.
PID parameters optimization for deicing robot joint controller.%除冰机器人关节控制PID参数优化
Institute of Scientific and Technical Information of China (English)
谢岚; 孙炜; 赵国瑞
2011-01-01
针对输电线除冰机器人的关节运动,提出一种改进的无刷直流电机控制策略,利用粒子群算法优化不完全微分控制算法来代替传统的PID控制,对Kp、Ti、Td进行全局优化·实验结果表明,该方法明显提高了控制性能,具有很强的鲁棒性,能够满足除冰机器人对控制系统高精度、实时性的要求.%To control the motion of the joints of deicing robot on power transmission line,an improved brushless DC motor control strategy is proposed,which utilizes PSO algorithm to optimize the parameters of PID controller with incomplete derivation instead of the traditional PID control.Three parameters of Kp, Ti , and Td are overall optimized. The results of experiments show that the control performance of the proposed method is improved dramatically and is highly robust which can meet high-precision and real-time requirements of the deicing robot.
Muharrem Imal
2015-01-01
Energy efficiency in heating, ventilating, and air-conditioning (HVAC) systems is a primary concern in process projects, since the energy consumption has the highest percentage in HVAC for all processes. Without sacrifice of thermal comfort, to reset the suitable operating parameters, such as the humidity and air temperature, would have energy saving with immediate effect. In this paper, the simulation-optimization approach described the effective energy efficiency for HVAC systems which are ...
Applied multivariate statistics with R
Zelterman, Daniel
2015-01-01
This book brings the power of multivariate statistics to graduate-level practitioners, making these analytical methods accessible without lengthy mathematical derivations. Using the open source, shareware program R, Professor Zelterman demonstrates the process and outcomes for a wide array of multivariate statistical applications. Chapters cover graphical displays, linear algebra, univariate, bivariate and multivariate normal distributions, factor methods, linear regression, discrimination and classification, clustering, time series models, and additional methods. Zelterman uses practical examples from diverse disciplines to welcome readers from a variety of academic specialties. Those with backgrounds in statistics will learn new methods while they review more familiar topics. Chapters include exercises, real data sets, and R implementations. The data are interesting, real-world topics, particularly from health and biology-related contexts. As an example of the approach, the text examines a sample from the B...
Multivariate Modelling via Matrix Subordination
DEFF Research Database (Denmark)
Nicolato, Elisa
Extending the vast library of univariate models to price multi-asset derivatives is still a challenge in the field of Quantitative Finance. Within the literature on multivariate modelling, a dichotomy may be noticed. On one hand, the focus has been on the construction of models displaying...... stochastic correlation within the framework of discussion processes (see e.g. Pigorsh and Stelzer (2008), Hubalek and Nicolato (2008) and Zhu (2000)). On the other hand a number of authors have proposed multivariate Levy models, which allow for flexible modelling of returns, but at the expenses of a constant...... correlation structure (see e.g. Leoni and Schoutens (2007) and Leoni and Schoutens (2007) among others). Tractable multivariate models displaying flexible and stochastic correlation structures combined with jumps is proving to be rather problematic. In particular, the classical technique of introducing...
Multivariable q-Racah polynomials
Van Diejen, J F
1996-01-01
The Koornwinder-Macdonald multivariable generalization of the Askey-Wilson polynomials is studied for parameters satisfying a truncation condition such that the orthogonality measure becomes discrete with support on a finite grid. For this parameter regime the polynomials may be seen as a multivariable counterpart of the (one-variable) q-Racah polynomials. We present the discrete orthogonality measure, expressions for the normalization constants converting the polynomials into an orthonormal system (in terms of the normalization constant for the unit polynomial), and we discuss the limit q\\rightarrow 1 leading to multivariable Racah type polynomials. Of special interest is the situation that q lies on the unit circle; in that case it is found that there exists a natural parameter domain for which the discrete orthogonality measure (which is complex in general) becomes real-valued and positive. We investigate the properties of a finite-dimensional discrete integral transform for functions over the grid, whose ...
Institute of Scientific and Technical Information of China (English)
Tan Guanzheng(谭冠政); Xiao Hongfeng; Wang Yuechao
2004-01-01
A new kind of optimal fuzzy PID controller is proposed, which contains two parts. One is an on-line fuzzy inference mechanism and another is a conventional PID controller. In the fuzzy inference mechanism, three adjustable factors xp, xi, and xd are introduced. Their function is to further modify and optimize the result of the fuzzy inference to make the controller have the optimal control effect on a given object. The optimal values of these factors are determined based on the ITAE criterion and the flexible polyhedron search algorithm of Nelder and Mead. This PID controller has been used to control a D.C. motor of the intelligent artificial leg designed by the authors. The result of computer simulation indicates that the design of this controller is very effective and can be widely used to control different kinds of objects and processes.
Directory of Open Access Journals (Sweden)
Jesus Patricio Ordaz Oliver
2015-01-01
Full Text Available This paper presents a stability analysis for LNDS (Lagrangian nonlinear dynamical systems with dynamic uncertain using a PID controller with external disturbances rejection based on attractive ellipsoid methods, since the PID-CT (proportional integral derivative computed torque compensator has been used for the nonlinear trajectory tracking of an LNDS, when there are external perturbations and system uncertainties. The global system convergence of the trivial solution has not been proved. In this sense, we propose an approach to find the gains of the nonlinear PID-CT controller to guarantee the boundedness of the trivial solution by means of the concept of the UUB (uniform-ultimately bounded stability. In order to show the effectiveness of the methodology proposed, we applied it in a real 2-DoF robot system.
Optimization of PID Parameter In Control System Tuning With Multi-Objective Genetic Algorithm.
Directory of Open Access Journals (Sweden)
Md Amanullah
2014-05-01
Full Text Available Way of playing advancement is the out-standing design of the study of PID control and frequently research work has been guided for this aspiration. The Proportional plus Integral plus Derivative (PID, controllers are most sweepingly used in control theory as well as industrial plants owing to their ease of execution and sturdiness way of playing. The aspiration of this deed representation capable and apace tuning approach using Genetic Algorithm (GA to obtain the optimized criterion of the PID controller so as to acquire the essential appearance designation of the technique below meditation. The make perfect achievement about multiple plants have in relation to the established tuning approach, to consider the ability of intended approach. Mostly, the whole system’s performance powerfully depends on the controller’s proficiency and thus the tuning technique plays a key part in the system’s behavior.
Application of PID controller to 2D differential geometric guidance problem
Institute of Scientific and Technical Information of China (English)
Chaoyong LI; Wuxing JING
2007-01-01
This paper presents the application of the proportional-integral-derivative (PID) controller to the flight control system (FCS) for two-dimensional (2D) differential geometric (DG) guidance and control problem. In particular,the performance of the designed FCS is investigated. To this end, the commanded angle-of-attack is firstly developed in the time domain using the classical DG formulations. Then, the classical PID controller is introduced to develop a FCS so as to form the 2D DG guidance and control system, and the PID controller parameters are determined by the Ziegler-Nichols method as well as the Routh-Hurwitz stability algorithm to guarantee the convergence of the system error. The results demonstrate that the designed controller yields a fast responding system, and the resulting DG guidance and control system is viable and effective in a realistic missile defense engagement.
Optimal PID Controller Design Based on PSO-RBFNN for Wind Turbine Systems
Directory of Open Access Journals (Sweden)
Jau-Woei Perng
2014-01-01
Full Text Available A strategy was proposed to determine the optimal operating point for the proportional-integral-derivative (PID controller of a wind turbine, and identify the stability regions in the parameter space. The proposed approach combined particle swarm optimization (PSO and radial basis function neural network (RBFNN algorithms. These intelligent algorithms are artificial learning mechanisms that can determine the optimal operating points, and were used to generate the function representing the most favorable operating parameters from each parameter of for the stability region of the PID controller. A graphical method was used to determine the 2D or 3D vision boundaries of the PID-type controller space in closed-loop wind turbine systems. The proposed techniques were demonstrated using simulations of a drive train model without time delay and a pitch control model with time delay. Finally, the 3D stability boundaries were determined the proposed graphical approach with and without time delay systems.
Speed Control System on Marine Diesel Engine Based on a Self-Tuning Fuzzy PID Controller
Directory of Open Access Journals (Sweden)
Naeim Farouk
2012-03-01
Full Text Available The degree of speed control of ship machinery effects on the economics and optimization of the machinery configuration and operation. All marine vessel ranging need some sort of speed control system to control and govern the speed of the marine diesel engines. This study presents a self-tuning fuzzy PID control system for speed control system of marine diesel engine. The system under consideration is a fourth-order plant with highly dynamic and uncertain environments. The current speed controllers for marine/traction diesel engines based on PID Controller cannot fully handle the uncertainties associated with such dynamic environments. A fuzzy logic control algorithm is used to estimate the PID coefficients in order to handle such uncertainties to produce a better control performance. Simulation tests were established using Simulink of MATLAB. The obtained results have demonstrated the feasibility and effectiveness of the proposed approach. Simulation results are represented in this study.
Control of suspended low-gravity simulation system based on self-adaptive fuzzy PID
Chen, Zhigang; Qu, Jiangang
2017-09-01
In this paper, an active suspended low-gravity simulation system is proposed to follow the vertical motion of the spacecraft. Firstly, working principle and mathematical model of the low-gravity simulation system are shown. In order to establish the balance process and suppress the strong position interference of the system, the idea of self-adaptive fuzzy PID control strategy is proposed. It combines the PID controller with a fuzzy controll strategy, the control system can be automatically adjusted by changing the proportional parameter, integral parameter and differential parameter of the controller in real-time. At last, we use the Simulink tools to verify the performance of the controller. The results show that the system can reach balanced state quickly without overshoot and oscillation by the method of the self-adaptive fuzzy PID, and follow the speed of 3m/s, while simulation degree of accuracy of system can reach to 95.9% or more.
Institute of Scientific and Technical Information of China (English)
LI Yin-ya; SHENG An-dong; WANG Yuan-gang
2007-01-01
A novel design method for determining the proportional-integral-derivative(PID) controller gains of an anti-aircraft artillery servo system with multiple performance specifications based on a particle swarm optimization (PSO) algorithm is proposed. First, a performance criterion evolution function combined with the system maximum displacement settling time, rise time, overshoot, steady state error, constant velocity tracking error and sine wave tracking error is defined. Second, the optimization problem of PID controller parameters and the searching procedure of PSO algorithm are constructed. Finally, the optimal or near optimal PID controller parameters are fast and easily obtained by solving the above optimization problem on the given controller parameter space following the PSO searching procedure. The simulation results show the effectiveness of the proposed controllers.
Optimal fuzzy PID controller with adjustable factors based on flexible polyhedron search algorithm
Institute of Scientific and Technical Information of China (English)
谭冠政; 肖宏峰; 王越超
2002-01-01
A new kind of optimal fuzzy PID controller is proposed, which contains two parts. One is an on-line fuzzy inference system, and the other is a conventional PID controller. In the fuzzy inference system, three adjustable factors xp, xi, and xd are introduced. Their functions are to further modify and optimize the result of the fuzzy inference so as to make the controller have the optimal control effect on a given object. The optimal values of these adjustable factors are determined based on the ITAE criterion and the Nelder and Mead′s flexible polyhedron search algorithm. This optimal fuzzy PID controller has been used to control the executive motor of the intelligent artificial leg designed by the authors. The result of computer simulation indicates that this controller is very effective and can be widely used to control different kinds of objects and processes.
A complex control system based on the fuzzy PID control and state predictor feedback control
Institute of Scientific and Technical Information of China (English)
Zhengxi Li; Jie Liu; Dehui Sun; Rentao Zhao
2004-01-01
A multi-mode adaptive controller was proposed. The controller features in the combination of Bang-bang and Fuzzy PID controls with state predictor. When large error exists, the controller operates in Bang-bang mode, otherwise it works as a fuzzy PID controller. For only few parameters to be adjusted, the real time controlled system achieveed good stability and fast response. Furthermore, the introduction of state observer was also discussed to extend the capability of the proposed controller to the plant with time-delay factors. The classical PID controller and the multi-mode controller were applied to the same second-order system successively. By comparison of the simulation results, the effectiveness of the controller were shown. At last, on electric-wire production line, this approach was practiced to control electric-wire diameter with an additive random disturbance signal. The test result further proved the effectiveness of the multi-mode controller.
MATTER-ELEMENT MODELING OF PARALLEL STRUCTURE AND APPLICATION ABOUT EXTENSION PID CONTROL SYSTEM
Institute of Scientific and Technical Information of China (English)
Rongde LU; Zonghai CHEN
2006-01-01
This article describes in detail a new method via the extension predictable algorithm of the matter-element model of parallel structure tuning the parameters of the extension PID controller. In comparison with fuzzy and extension PID controllers, the proposed extension PID predictable controller shows higher control gains when system states are away from equilibrium, and retains a lower profile of control signals at the same time. Consequently, better control performance is achieved. Through the proposed tuning formula, the weighting factors of an extension-logic predictable controller can be systematically selected according to the control plant. An experimental example through industrial field data and site engineers' experience demonstrates the superior performance of the proposed controller over the fuzzy controller.
New tuning conditions for a class of nonlinear PID global regulators of robot manipulators
Orrante-Sakanassi, Jorge; Santibánez, Victor; Hernández-Guzmán, Victor M.
2014-04-01
Several nonlinear proportional-integral-derivative (PID) controllers for robot manipulators that ensure global asymptotic stability have been proposed in the literature. However, the tuning criteria obtained are expressed in terms of conditions so restrictive that they have avoided, until now, carrying out experimental tests with such controllers. Tuning criteria of some PID controllers for robot manipulators with conditions more relaxed than those presented previously in the literature have been proposed in two recent works by the authors. This was achieved by setting the tuning conditions individually for each joint instead of general conditions for the whole robot. In this paper we extend these results to a class of nonlinear PID global regulators for robot manipulators. The obtained tuning criteria are given in terms of conditions so relaxed that they have allowed to carry out, for the first time, experimental essays with these controllers. Such experiments are presented in this paper using a two-degrees-of-freedom robot manipulator.
PID controller auto-tuning based on process step response and damping optimum criterion.
Pavković, Danijel; Polak, Siniša; Zorc, Davor
2014-01-01
This paper presents a novel method of PID controller tuning suitable for higher-order aperiodic processes and aimed at step response-based auto-tuning applications. The PID controller tuning is based on the identification of so-called n-th order lag (PTn) process model and application of damping optimum criterion, thus facilitating straightforward algebraic rules for the adjustment of both the closed-loop response speed and damping. The PTn model identification is based on the process step response, wherein the PTn model parameters are evaluated in a novel manner from the process step response equivalent dead-time and lag time constant. The effectiveness of the proposed PTn model parameter estimation procedure and the related damping optimum-based PID controller auto-tuning have been verified by means of extensive computer simulations.
Design of PID controllers in double feedback loops for SISO systems with set-point filters.
Vijayan, V; Panda, Rames C
2012-07-01
A PID controller is widely used to control industrial processes that are mostly open loop stable or unstable. Selection of proper feedback structure and controller tuning helps to improve the performance of the loop. In this paper a double-feedback loop/method is used to achieve stability and better performance of the process. The internal feedback is used for stabilizing the process and the outer loop is used for good setpoint tracking. An internal model controller (IMC) based PID method is used for tuning the outer loop controller. Autotuning based on relay feedback or the Ziegler-Nichols method can be used for tuning an inner loop controller. A tuning parameter (λ) that is used to tune IMC-PID is used as a time constant of a setpoint filter that is used for reducing the peak overshoot. The method has been tested successfully on many low order processes.
Directory of Open Access Journals (Sweden)
V. Balaji
2016-12-01
Full Text Available pH control plays a important role in any chemical plant and process industries. For the past four decades the classical PID controller has been occupied by the industries. Due to the faster computing technology in the industry demands a tighter advanced control strategy. To fulfill the needs and requirements Model Predictive Control (MPC is the best among all the advanced control algorithms available in the present scenario. The study and analysis has been done for First Order plus Delay Time (FOPDT model controlled by Proportional Integral Derivative (PID and MPC using the Matlab software. This paper explores the capability of the MPC strategy, analyze and compare the control effects with conventional control strategy in pH control. A comparison results between the PID and MPC is plotted using the software. The results clearly show that MPC provide better performance than the classical controller.
CONTROL OF CONCENTRATION IN CSTR USING DMC AND CONVENTIONAL PID BASED ON RELAY FEEDBACK METHOD
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S. SRINIVASULU RAJU
2013-04-01
Full Text Available This paper presents the design of a Dynamic Matrix Controller (DMC is analyzed for concentration control of Continuous Stirred Tank Reactors (CSTRs which have strong nonlinearities. Various control approaches have been applied on CSTR to control its parameters. All the industrial process applications require solutions of a specific chemical strength of the chemicals or fluids considered for analysis. Such specific concentrations are achieved by mixing a full strength solution with water in the desired proportions. For this, we use twocontrollers DMC and PID and analyzed. The basic PID controllers have difficulty in dealing with complex nonlinear processes. Simulation studies give satisfactory results. In this paper the control the concentration of one chemical with the help of other has been analyzed. Model design and simulation are done in MATLAB/SIMULINK, using programming. The concentration control is found better controlled with the addition of DMC instead of PID controller solely.
PID self tuning control based on Mamdani fuzzy logic control for quadrotor stabilization
Energy Technology Data Exchange (ETDEWEB)
Priyambodo, Tri Kuntoro, E-mail: mastri@ugm.ac.id; Putra, Agfianto Eko [Aerospace and Aeronautics Electronics Research Group, Universitas Gadjah Mada, Yogyakarta (Indonesia); Department of Computer Science and Electronics, Universitas Gadjah Mada, Yogyakarta (Indonesia); Dharmawan, Andi, E-mail: andi-dharmawan@ugm.ac.id [Department of Computer Science and Electronics, Universitas Gadjah Mada, Yogyakarta (Indonesia)
2016-02-01
Quadrotor as one type of UAV have the ability to perform Vertical Take Off and Landing (VTOL). It allows the Quadrotor to be stationary hovering in the air. PID (Proportional Integral Derivative) control system is one of the control methods that are commonly used. It is usually used to optimize the Quadrotor stabilization at least based on the three Eulerian angles (roll, pitch, and yaw) as input parameters for the control system. The three constants of PID can be obtained in various methods. The simplest method is tuning manually. This method has several weaknesses. For example if the three constants are not exact, the resulting response will deviate from the desired result. By combining the methods of PID with fuzzy logic systems where human expertise is implemented into the machine language is expected to further optimize the control system.
Multivariate Analysis for the Processing of Signals
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Beattie J.R.
2014-01-01
Full Text Available Real-world experiments are becoming increasingly more complex, needing techniques capable of tracking this complexity. Signal based measurements are often used to capture this complexity, where a signal is a record of a sample’s response to a parameter (e.g. time, displacement, voltage, wavelength that is varied over a range of values. In signals the responses at each value of the varied parameter are related to each other, depending on the composition or state sample being measured. Since signals contain multiple information points, they have rich information content but are generally complex to comprehend. Multivariate Analysis (MA has profoundly transformed their analysis by allowing gross simplification of the tangled web of variation. In addition MA has also provided the advantage of being much more robust to the influence of noise than univariate methods of analysis. In recent years, there has been a growing awareness that the nature of the multivariate methods allows exploitation of its benefits for purposes other than data analysis, such as pre-processing of signals with the aim of eliminating irrelevant variations prior to analysis of the signal of interest. It has been shown that exploiting multivariate data reduction in an appropriate way can allow high fidelity denoising (removal of irreproducible non-signals, consistent and reproducible noise-insensitive correction of baseline distortions (removal of reproducible non-signals, accurate elimination of interfering signals (removal of reproducible but unwanted signals and the standardisation of signal amplitude fluctuations. At present, the field is relatively small but the possibilities for much wider application are considerable. Where signal properties are suitable for MA (such as the signal being stationary along the x-axis, these signal based corrections have the potential to be highly reproducible, and highly adaptable and are applicable in situations where the data is noisy or
Multivariate stochastic simulation with subjective multivariate normal distributions
P. J. Ince; J. Buongiorno
1991-01-01
In many applications of Monte Carlo simulation in forestry or forest products, it may be known that some variables are correlated. However, for simplicity, in most simulations it has been assumed that random variables are independently distributed. This report describes an alternative Monte Carlo simulation technique for subjectively assesed multivariate normal...
Heave Compensation System Based on Hybrid Fuzzy P+ID Control%基于混合模糊P+ID控制的升沉补偿系统
Institute of Scientific and Technical Information of China (English)
陈琦; 李伟; 王晓辉; 张奇峰; 张巍
2016-01-01
提出一种混合模糊P+ID控制算法，并将其应用于采用电控液压绞车的升沉补偿控制系统，使水下机器人在作业时不受母船升沉运动的影响。首先采用数字高通滤波器对惯性测量单元（IMU）获得的数据进行处理，计算出母船升沉运动的位移。然后推导出电控液压绞车系统的数学模型，并设计了基于混合模糊P+ID的升沉补偿控制器，根据母船升沉位移来控制液压绞车转动。最后通过仿真实验和物理平台实验验证证明了基于混合模糊P+ID的升沉补偿系统比常规PID系统有着更好的鲁棒性。%A hybrid fuzzy P+ID controller is proposed and applied to the heave compensation system using an electro-hydraulic winch system. The heave compensation system can decouple the operation of underwater vehicle from the motion of vessel. Firstly, the heave motion of vessel is calculated based on measurements from an inertial measurement unit (IMU) using a digital high-pass filter. Then, a mathematical model of the electro-hydraulic winch system is developed, and the heave compensation controller based on hybrid fuzzy P+ID controller is designed to control the winch rotation according to the vessel motion. Finally, simulation studies and real device experiments are conducted to demonstrate that the heave compensation systems based on the fuzzy P+ID controller is much more robust than the conventional PID controller.
Adaptive fuzzy PID temperature control system based on single-chip computer for the autoclave
Zhang, F.; Wang, J.; Fu, S. L.; He, Z. T.; Li, X. P.
2008-12-01
The autoclave is one of main preparation equipments of crystal preparation by hydrothermal method. The preparation temperature will seriously influence crystals quality and crystals size at high temperature, how to measure and control precisely the autoclave temperature can be of real significance. The characteristic of hysteresis, nonlinearity and difficulty to acquire the precise mathematical model existing in the temperature control of the autoclave was researched. The general PID controller adopted usually in the autoclave temperature control system is hard to improve temperature control performance. Based on the advantages of fuzzy controller that does not depend on the precise mathematical model and the stabilization of PID controller, single-chip computer integrated fuzzy PID control algorithm is adopted, and the temperature system is designed, the foundational working principle was discussed. The control system includes SCM (AT89C52), temperature sensor, A/D converter circuit and corresponding circuit and interface, can make the autoclave temperature measure and control accurately. The system hardware includes main circuit, thyristor drive circuit, audible and visual alarm circuit, watchdog circuit, clock circuit, keyboard and display circuit so on, which can achieve gathering, analyzing, comparing and controlling the autoclave temperature parameter. The program of control system includes the treatment and collection of temperature data, the dynamic display program, the fuzzy PID control system, the audible and visual alarm program, et al, and the system's main software, which includes initialization, key-press processing, input processing, display, and the fuzzy PID control program was analyzed. The results showed that the fuzzy PID control system makes the adjustment time of temperature decreased and the precision of temperature control improved, the quality and the crystals size of the preparation crystals can achieve the expect experiment results.
Control de velocidad de un motor de CD con un controlador PID Wavenet
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Abraham Christian Pedroza Araujo
2014-01-01
Full Text Available El controlador más utilizado actualmente en la industria es el controlador PID. Sin embargo, el algoritmo PID lineal tiene bajo desempeño cuando el proceso a controlar presenta dinámicas complejas como zonas muertas y características no lineales. El funcionamiento del controlador PID en general, se basa en la actuación en forma proporcional, integral y derivativa sobre la señal de error e(t, definida como e(t = yref(t - y(t, con la finalidad de efectuar la señal de control u(t que manipula la salida del proceso en forma deseada como se muestra la Figura 1. Figura 1. Esquema de un control clásico. Figura 1. Esquema de un control clásico. Las constantes kp ki kd son las ganancias del PID. Existen distintas técnicas analíticas y experimentales con el fin de sintonizar esas ganancias. Una alternativa a este problema de sintonización es el controlador PID wavenet, donde por medio de una wavenet y un filtro IIR se estima la salida del sistema a controlar, lo cual se utiliza para re-sintonizar las ganancias de un PID discreto, todo esto en línea. Esta es la alternativa que se emplea en el presente trabajo de investigación y enfocada a la simulación y control de un motor de cd obteniendo resultados.
Neural Network-Based Self-Tuning PID Control for Underwater Vehicles
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Rodrigo Hernández-Alvarado
2016-09-01
Full Text Available For decades, PID (Proportional + Integral + Derivative-like controllers have been successfully used in academia and industry for many kinds of plants. This is thanks to its simplicity and suitable performance in linear or linearized plants, and under certain conditions, in nonlinear ones. A number of PID controller gains tuning approaches have been proposed in the literature in the last decades; most of them off-line techniques. However, in those cases wherein plants are subject to continuous parametric changes or external disturbances, online gains tuning is a desirable choice. This is the case of modular underwater ROVs (Remotely Operated Vehicles where parameters (weight, buoyancy, added mass, among others change according to the tool it is fitted with. In practice, some amount of time is dedicated to tune the PID gains of a ROV. Once the best set of gains has been achieved the ROV is ready to work. However, when the vehicle changes its tool or it is subject to ocean currents, its performance deteriorates since the fixed set of gains is no longer valid for the new conditions. Thus, an online PID gains tuning algorithm should be implemented to overcome this problem. In this paper, an auto-tune PID-like controller based on Neural Networks (NN is proposed. The NN plays the role of automatically estimating the suitable set of PID gains that achieves stability of the system. The NN adjusts online the controller gains that attain the smaller position tracking error. Simulation results are given considering an underactuated 6 DOF (degrees of freedom underwater ROV. Real time experiments on an underactuated mini ROV are conducted to show the effectiveness of the proposed scheme.
Neural Network-Based Self-Tuning PID Control for Underwater Vehicles.
Hernández-Alvarado, Rodrigo; García-Valdovinos, Luis Govinda; Salgado-Jiménez, Tomás; Gómez-Espinosa, Alfonso; Fonseca-Navarro, Fernando
2016-09-05
For decades, PID (Proportional + Integral + Derivative)-like controllers have been successfully used in academia and industry for many kinds of plants. This is thanks to its simplicity and suitable performance in linear or linearized plants, and under certain conditions, in nonlinear ones. A number of PID controller gains tuning approaches have been proposed in the literature in the last decades; most of them off-line techniques. However, in those cases wherein plants are subject to continuous parametric changes or external disturbances, online gains tuning is a desirable choice. This is the case of modular underwater ROVs (Remotely Operated Vehicles) where parameters (weight, buoyancy, added mass, among others) change according to the tool it is fitted with. In practice, some amount of time is dedicated to tune the PID gains of a ROV. Once the best set of gains has been achieved the ROV is ready to work. However, when the vehicle changes its tool or it is subject to ocean currents, its performance deteriorates since the fixed set of gains is no longer valid for the new conditions. Thus, an online PID gains tuning algorithm should be implemented to overcome this problem. In this paper, an auto-tune PID-like controller based on Neural Networks (NN) is proposed. The NN plays the role of automatically estimating the suitable set of PID gains that achieves stability of the system. The NN adjusts online the controller gains that attain the smaller position tracking error. Simulation results are given considering an underactuated 6 DOF (degrees of freedom) underwater ROV. Real time experiments on an underactuated mini ROV are conducted to show the effectiveness of the proposed scheme.
Neural Network-Based Self-Tuning PID Control for Underwater Vehicles
Hernández-Alvarado, Rodrigo; García-Valdovinos, Luis Govinda; Salgado-Jiménez, Tomás; Gómez-Espinosa, Alfonso; Fonseca-Navarro, Fernando
2016-01-01
For decades, PID (Proportional + Integral + Derivative)-like controllers have been successfully used in academia and industry for many kinds of plants. This is thanks to its simplicity and suitable performance in linear or linearized plants, and under certain conditions, in nonlinear ones. A number of PID controller gains tuning approaches have been proposed in the literature in the last decades; most of them off-line techniques. However, in those cases wherein plants are subject to continuous parametric changes or external disturbances, online gains tuning is a desirable choice. This is the case of modular underwater ROVs (Remotely Operated Vehicles) where parameters (weight, buoyancy, added mass, among others) change according to the tool it is fitted with. In practice, some amount of time is dedicated to tune the PID gains of a ROV. Once the best set of gains has been achieved the ROV is ready to work. However, when the vehicle changes its tool or it is subject to ocean currents, its performance deteriorates since the fixed set of gains is no longer valid for the new conditions. Thus, an online PID gains tuning algorithm should be implemented to overcome this problem. In this paper, an auto-tune PID-like controller based on Neural Networks (NN) is proposed. The NN plays the role of automatically estimating the suitable set of PID gains that achieves stability of the system. The NN adjusts online the controller gains that attain the smaller position tracking error. Simulation results are given considering an underactuated 6 DOF (degrees of freedom) underwater ROV. Real time experiments on an underactuated mini ROV are conducted to show the effectiveness of the proposed scheme. PMID:27608018
Tuning PID controllers for higher-order oscillatory systems with improved performance.
Malwatkar, G M; Sonawane, S H; Waghmare, L M
2009-07-01
In this paper, model based design of PID controllers is proposed for higher-order oscillatory systems. The proposed method has no limitations regarding systems order, time delays and oscillatory behavior. The reduced model is achieved based on third-order modeling and selection of coefficients through the use of frequency responses. The tuning of the PID parameters are obtained from a reduced third-order model; the procedure seems to be simple and effective, and improved performance of the overall system can be achieved. Three simulation examples and one real-time experiment are included to demonstrate the effectiveness and applicability of the proposed method to systems with oscillatory behavior.