Louis, Jean-Paul
2013-01-01
Synchronous motors are indubitably the most effective device to drive industrial production systems and robots with precision and rapidity. Their control law is thus critical for combining at the same time high productivity to reduced energy consummation. As far as possible, the control algorithms must exploit the properties of these actuators. Therefore, this work draws on well adapted models resulting from the Park's transformation, for both the most traditional machines with sinusoidal field distribution and for machines with non-sinusoidal field distribution which are more and more used in
Generalized synchronization via impulsive control
International Nuclear Information System (INIS)
Zhang Rong; Xu Zhenyuan; Yang, Simon X.; He Xueming
2008-01-01
This paper demonstrates theoretically that two completely different systems can implement GS via impulsive control, moreover by using impulsive control, for a given manifold y = H(x) we construct a response system to achieve GS with drive system and the synchronization manifold is y = H(x). Our theoretical results are supported by numerical examples
Control of non-conventional synchronous motors
Louis, Jean-Paul
2013-01-01
Classical synchronous motors are the most effective device to drive industrial production systems and robots with precision and rapidity. However, numerous applications require efficient controls in non-conventional situations. Firstly, this is the case with synchronous motors supplied by thyristor line-commutated inverters, or with synchronous motors with faults on one or several phases. Secondly, many drive systems use non-conventional motors such as polyphase (more than three phases) synchronous motors, synchronous motors with double excitation, permanent magnet linear synchronous motors,
Control for a synchronization-desynchronization switch
He, Zhiwei; Wang, Xingang; Zhang, Guo-Yong; Zhan, Meng
2014-07-01
How to freely enhance or suppress synchronization of networked dynamical systems is of great importance in many disciplines. A unified precise control method for a synchronization-desynchronization switch, called the pull-push control method, is suggested. Namely, synchronization can be achieved when the original systems are desynchronous by pulling (or protecting) one node or a certain subset of nodes, whereas desynchronization can be accomplished when the systems are already synchronous by pushing (or kicking) one node or a certain subset of nodes. With this method, the controlled nodes should be chosen by the generalized eigenvector centrality of the critical synchronization mode of the Laplacian matrix. Compared with existing control methods for synchronization, it displays high efficiency, flexibility, and precision as well.
Control of partial synchronization in chaotic oscillators
Indian Academy of Sciences (India)
2015-02-07
Feb 7, 2015 ... Abstract. A design of coupling is proposed to control partial synchronization in two chaotic oscil- lators in a driver–response mode. A control of synchrony between one response variables is made possible (a transition from a complete synchronization to antisynchronization via amplitude death and vice ...
Huang, Chengdai; Cao, Jinde
2017-05-01
This paper is concerned with the issues of synchronization and anti-synchronization for fractional chaotic financial system with market confidence by taking advantage of active control approach. Some sufficient conditions are derived to guarantee the synchronization and anti-synchronization for the proposed fractional system. Moreover, the relationship between the order and synchronization(anti-synchronization) is demonstrated numerically. It reveals that synchronization(anti-synchronization) is faster as the order increases. Finally, two illustrative examples are exploited to verify the efficiency of the obtained theoretical results.
Adaptive Control Algorithm of the Synchronous Generator
Directory of Open Access Journals (Sweden)
Shevchenko Victor
2017-01-01
Full Text Available The article discusses the the problem of controlling a synchronous generator, namely, maintaining the stability of the control object in the conditions of occurrence of noise and disturbances in the regulatory process. The model of a synchronous generator is represented by a system of differential equations of Park-Gorev, where state variables are computed relative to synchronously rotating d, q-axis. Management of synchronous generator is proposed to organize on the basis of the position-path control using algorithms to adapt with the reference model. Basic control law directed on the stabilizing indicators the frequency generated by the current and the required power level, which is achieved by controlling the mechanical torque on the shaft of the turbine and the value of the excitation voltage of the synchronous generator. Modification of the classic adaptation algorithm using the reference model, allowing to minimize the error of the reference regulation and the model under investigation within the prescribed limits, produced by means of the introduction of additional variables controller adaptation in the model. Сarried out the mathematical modeling of control provided influence on the studied model of continuous nonlinear and unmeasured the disturbance. Simulation results confirm the high level accuracy of tracking and adaptation investigated model with respect to the reference, and the present value of the loop error depends on parameters performance of regulator.
Control of a superconducting synchronous motor
International Nuclear Information System (INIS)
Jiang, Y; Pei, R; Jiang, Q; Hong, Z; Coombs, T A
2007-01-01
This paper presents a control algorithm for starting up a high temperature superconducting synchronous motor. The mathematical model of the motor has been established in m-file in Matlab and the parameters have been identified by means of the finite-element analysis method. Different starting methods for the motor have been compared and discussed, and eventually a hybrid control algorithm is proposed
Chaos synchronization in autonomous chaotic system via hybrid feedback control
International Nuclear Information System (INIS)
Yang Lixin; Chu Yandong; Zhang Jiangang; Li Xianfeng; Chang Yingxiang
2009-01-01
This paper presents the synchronization of chaos by designing united controller. First, this method is implemented in synchronization of a simple system, then we realize the synchronization of Lue hyperchaotic system, we also take tracking control to realize the synchronization of Lue hyperchaotic system. Comparing with results, we can find that hybrid feedback control approach is more effective than tracking control for hyperchaotic system. Numerical simulations show the united synchronization method works well.
Controlled Limiter in the Synchronous Detection Circuit
Directory of Open Access Journals (Sweden)
Yauheni Bialetski
2017-07-01
Full Text Available This variant of construction of the electrical circuit is aimed at reducing the effects of impulse noise. The measuring channels of the primary transducers are subject to interference of various types. In the case of a small ratio between a useful signal and noise level, synchronous detection is used. Impulse noise leaves a big mark even after using synchronous detection. To improve the performance of such measuring devices, it is proposed to use a controlled amplitude limiter at the input. Comparative analysis of solutions with controlled limiters is carried out in the article and conditions for its optimal operation are determined.
Synchronous generator wind energy conversion control system
Energy Technology Data Exchange (ETDEWEB)
Medeiros, A.L.R. [Wind Energy Group, Recife (Brazil); Lima, A.M.N.; Jacobina, C.B.; Simoes, F.J. [DEE, Campina Grande (Brazil)
1996-12-31
This paper presents the performance evaluation and the design of the control system of a WECS (Wind Energy Conversion System) that employs a synchronous generator based on its digital simulation. The WECS discussed in this paper is connected to the utility grid through two Pulse Width Modulated (PWM) power converters. The structure of the proposed WECS enables us to achieve high performance energy conversion by: (i) maximizing the wind energy capture and (ii) minimizing the reactive power flowing between the grid and the synchronous generator. 8 refs., 19 figs.
Synchronous Control of Modular Multilevel Converters
DEFF Research Database (Denmark)
Oleschuk, Valentin; Blaabjerg, Frede; Bose, Bimal K.
2002-01-01
A novel method of direct synchronous pulsewidth modulation (PWM) is applied for control of modular multilevel converters consisting from three standard triphase inverter modules along with an 0.33 p.u. output transformer. The proposed method provides synchronisation of the voltage waveforms...... for each module and the composed voltage at the output of the converter. Multilevel output voltage of the converter has quarter-wave symmetry during the whole range including the zone of overmodulation. Both continuous and discontinuous versions of synchronous PWM, based on vector approach...
Hyperchaos control and adaptive synchronization with uncertain ...
Indian Academy of Sciences (India)
Mathieu and van der Pol equations, for studying dynamical behaviour, chaos control and its synchronization. The van der Pol oscillator is a nonconservative oscillator with nonlinear damping. Due to this feature, it has become popular for systems with limit cycle oscillations in physics, biology, sociology and even economics.
Synchronous Control Method and Realization of Automated Pharmacy Elevator
Liu, Xiang-Quan
Firstly, the control method of elevator's synchronous motion is provided, the synchronous control structure of double servo motor based on PMAC is accomplished. Secondly, synchronous control program of elevator is implemented by using PMAC linear interpolation motion model and position error compensation method. Finally, the PID parameters of servo motor were adjusted. The experiment proves the control method has high stability and reliability.
Synchronization of the unified chaotic systems via active control
International Nuclear Information System (INIS)
Ucar, Ahmet; Lonngren, Karl E.; Bai Erwei
2006-01-01
This paper investigates the synchronization of coupled unified chaotic systems via active control. The synchronization is given in the slave-master scheme and the controller ensures that the states of the controlled chaotic slave system exponentially synchronize with the state of the master system. Numerical simulations are provided for illustration and verification of the proposed method
International Nuclear Information System (INIS)
Yan-Li, Zou; Guan-Rong, Chen
2009-01-01
This paper studies pinning-controlled synchronization of complex networks with bounded or unbounded synchronized regions. To study a state-feedback pinning-controlled network with N nodes, it first converts the controlled network to an extended network of N+1 nodes without controls. It is shown that the controlled synchronizability of the given network is determined by the real part of the smallest nonzero eigenvalue of the coupling matrix of its extended network when the synchronized region is unbounded; but it is determined by the ratio of the real parts of the largest and the smallest nonzero eigenvalues of the coupling matrix when the synchronized region is bounded. Both theoretical analysis and numerical simulation show that the portion of controlled nodes has no critical values when the synchronized region is unbounded, but it has a critical value when the synchronized region is bounded. In the former case, therefore, it is possible to control the network to achieve synchronization by pinning only one node. In the latter case, the network can achieve controlled synchronization only when the portion of controlled nodes is larger than the critical value. (general)
Multi-switching synchronization of chaotic systems with active controllers
International Nuclear Information System (INIS)
Ucar, Ahmet; Lonngren, Karl E.; Bai, Er-Wei
2008-01-01
This paper reports the results of an investigation of the multi-switching synchronization of coupled chaotic systems via active controls. The synchronization is achieved with the slave-master scheme, and it is extended to investigate the synchronization problems with different combinations of slave states with master systems. The different active controller are designed for the chosen slave system states to be synchronized with the target master system states. The multi-switching synchronization of Lorenz system is considered. Numerical simulations are provided for illustration and verification of the proposed method
Sensorless Control of Permanent Magnet Synchronous Machines
DEFF Research Database (Denmark)
Matzen, Torben N.
to replace the mechanical sensor with an indirect measurement. The main hardware components considered in a sensorless drive are the inverter, the PM synchronous machine and the current acquisition i.e transducers, interface circuits and sampling. These hardware parts are analysed with respect......Permanent magnet machines, with either surface mounted or embedded magnets on the rotor, are becoming more common due to the key advantages of higher energy conversion efficiency and higher torque density compared to the classical induction machine. Besides energy efficiency the permanent magnet...... machine is also used for servo applications where higher dynamics is required, e.g. in industrial automation. The energy efficiency is essential for battery powered electric vehicles where the electric storage capacity is limited by cost, mass and volume. The control system necessary to operate...
Sensorless V/f Control of Permanent Magnet Synchronous Motors
Montesinos-Miracle, Daniel; Perera, P. D. Chandana; Galceran-Arellano, Samuel; Blaabjerg, Frede
2010-01-01
V/f control strategy for permanent magnet synchronous motors can be useful for HVAC applications, where not high performance is required. Permanent magnet synchronous motors have efficiency advantages over the induction motor. But open loop V/f control is not stable in the whole frequency range. As demonstrated, the V/f control strategy becomes
Synchronized control of spiral CT scan for security inspection device
International Nuclear Information System (INIS)
Wang Jue; Jiang Zenghui; Wang Fuquan
2008-01-01
In security inspection system of spiral CT, the synchronization between removing and rotating, and the scan synchronization between rotating and sampling influence quality of image reconstruction, so it is difficulty and important that how to realize synchronized scan. According to the controlling demand of multi-slice Spiral CT, the method to realize synchronized scan is given. a synchronized control system is designed, in which we use a industrial PC as the control computer, use magnetic grids as position detectors, use alternating current servo motor and roller motor as drivers respectively drive moving axis and rotating axis. This method can solve the problem of synchronized scan, and has a feasibility and value of use. (authors)
Synchronization of Forced damped Pendulum via Active Control ...
African Journals Online (AJOL)
In this paper active controllers are designed to synchronize two identical forced damped pendula. The performance of the controllers in the synchronization of the chaotic dynamics of the two pendula, resulting from different initial conditions, is investigated numerically and found to be effective. Transition from ...
Distributed synchronization of coupled neural networks via randomly occurring control.
Tang, Yang; Wong, Wai Keung
2013-03-01
In this paper, we study the distributed synchronization and pinning distributed synchronization of stochastic coupled neural networks via randomly occurring control. Two Bernoulli stochastic variables are used to describe the occurrences of distributed adaptive control and updating law according to certain probabilities. Both distributed adaptive control and updating law for each vertex in a network depend on state information on each vertex's neighborhood. By constructing appropriate Lyapunov functions and employing stochastic analysis techniques, we prove that the distributed synchronization and the distributed pinning synchronization of stochastic complex networks can be achieved in mean square. Additionally, randomly occurring distributed control is compared with periodically intermittent control. It is revealed that, although randomly occurring control is an intermediate method among the three types of control in terms of control costs and convergence rates, it has fewer restrictions to implement and can be more easily applied in practice than periodically intermittent control.
Robust chaos synchronization using input-to-state stable control
Indian Academy of Sciences (India)
In this paper, we propose a new input-to-state stable (ISS) synchronization method for a general class of chaotic systems with disturbances. Based on Lyapunov theory and linear matrix inequality (LMI) approach, for the first time, the ISS synchronization controller is presented not only to guarantee the asymptotic ...
Deng, Zhenhua; Shang, Jing; Nian, Xiaohong
2015-11-01
In this paper, two coupling permanent magnet synchronous motors system with nonlinear constraints is studied. First of all, the mathematical model of the system is established according to the engineering practices, in which the dynamic model of motor and the nonlinear coupling effect between two motors are considered. In order to keep the two motors synchronization, a synchronization controller based on load observer is designed via cross-coupling idea and interval matrix. Moreover, speed, position and current signals of two motor all are taken as self-feedback signal as well as cross-feedback signal in the proposed controller, which is conducive to improving the dynamical performance and the synchronization performance of the system. The proposed control strategy is verified by simulation via Matlab/Simulink program. The simulation results show that the proposed control method has a better control performance, especially synchronization performance, than that of the conventional PI controller. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.
Fractional order control and synchronization of chaotic systems
Vaidyanathan, Sundarapandian; Ouannas, Adel
2017-01-01
The book reports on the latest advances in and applications of fractional order control and synchronization of chaotic systems, explaining the concepts involved in a clear, matter-of-fact style. It consists of 30 original contributions written by eminent scientists and active researchers in the field that address theories, methods and applications in a number of research areas related to fractional order control and synchronization of chaotic systems, such as: fractional chaotic systems, hyperchaotic systems, complex systems, fractional order discrete chaotic systems, chaos control, chaos synchronization, jerk circuits, fractional chaotic systems with hidden attractors, neural network, fuzzy logic controllers, behavioral modeling, robust and adaptive control, sliding mode control, different types of synchronization, circuit realization of chaotic systems, etc. In addition to providing readers extensive information on chaos fundamentals, fractional calculus, fractional differential equations, fractional contro...
Design and control of a superconducting permanent magnet synchronous motor
International Nuclear Information System (INIS)
Jiang, Y; Pei, R; Hong, Z; Song, J; Fang, F; Coombs, T A
2007-01-01
This paper gives a detailed description of the design of a superconducting permanent magnet synchronous motor. The parameters of the motor have been identified, and the torque equation has been stated. A direct torque control algorithm is introduced and applied to a traditional permanent magnet synchronous motor and the superconducting permanent magnet synchronous motor described in this paper. The motor performance shows that the direct torque control algorithm provides excellent control to the superconducting motor, and guarantees that the magnitude of the operational armature currents is smaller than the value of the critical current of the superconducting tape used for stator winding
Distributed Synchronization Control to Trajectory Tracking of Multiple Robot Manipulators
Directory of Open Access Journals (Sweden)
Yassine Bouteraa
2011-01-01
while tracking a common desired trajectory. Based on the well-known consensus algorithm, the control strategy consists in synchronizing the joint position and the velocity of each robot in the network with respect to neighboring robots' joints and velocities. Modeled by an undirected graph, the cooperative robot network requires just local neighbor-to-neighbor information exchange between manipulators. So, it does not assume the existence of an explicit leader in the team. Based above all on combination of Lyapunov direct method and cross-coupling strategy, the proposed decentralized control law is extended to an adaptive synchronization control taking into account parameter uncertainties. To address the time delay problems in the network communication channels, the suggested synchronization control law robustly synchronizes robots to track a given trajectory. To this end, Krasovskii functional method has been used to deal with the delay-dependent stability problem. A real-time software simulator is developed to visualize the robot manipulators coordination.
Indian Academy of Sciences (India)
Towards the end some real life exam- ples are also discussed. 1. Introduction. Synchronization, in simple terms, ..... certain relationship between their phases is termed as phase locking. GENERAL I ARTICLE ral frequencies beginning to oscillate at a common fre- quency owing to coupling is called frequency locking or.
Indian Academy of Sciences (India)
When a swarm of fireflies gather, they have been found to flash in synchrony. GENERAL I ARTICLE node is due to synchronization of the rhythms of the collection of pacemaker cells. In a pathological case, the pacemaker cells become faulty which results in an abnormally low heart rate known as bradycardia. This results in ...
Filippov systems and quasi-synchronization control for switched networks.
Liu, Xiaoyang; Cao, Jinde; Yu, Wenwu
2012-09-01
This paper is concerned with the quasi-synchronization issue of linearly coupled networks with discontinuous nonlinear functions in each isolated node. Under the framework of Filippov systems, the existence and boundedness of solutions for such complex networks can be guaranteed by the matrix measure approach. A design method is presented for the synchronization controllers of coupled networks with non-identical discontinuous systems. Moreover, a sufficient condition is derived to ensure the quasi-synchronization of switched coupled complex networks with discontinuous isolated nodes, which could be controlled by some designed linear controllers. The obtained results extend the previous work on the synchronization issue of coupled complex networks with Lipschitz continuous conditions. Numerical simulations on the coupled chaotic systems are given to demonstrate the effectiveness of the theoretical results.
Controlling chaos in the permanent magnet synchronous motor
International Nuclear Information System (INIS)
Zribi, Mohamed; Oteafy, Ahmed; Smaoui, Nejib
2009-01-01
The Permanent Magnet Synchronous Motor (PMSM) is known to exhibit chaotic behavior under certain conditions. This paper proposes to use an instantaneous Lyapunov exponent control algorithm to control the PMSM. One of the objectives of the control approach is to bring order to the PMSM and to drive it to any user-defined desired state. Simulation results under different operating conditions indicate that the proposed control scheme works well. Moreover, the proposed Lyapunov exponent control scheme is able to induce chaos on the permanent magnet synchronous motor. Simulation results show the effectiveness of the proposed control scheme in chaotifing the response of the motor.
Control of Permanent Magnet Synchronous Generator for large wind turbines
DEFF Research Database (Denmark)
Busca, Cristian; Stan, Ana-Irina; Stanciu, Tiberiu
2010-01-01
Direct Torque Control (DTC) and Field Oriented Control (FOC) are the most dominant control strategies used in generators for wind turbines. In this paper both control methods were implemented on a Permanent Magnet Synchronous Generator (PMSG). The variable speed wind turbine with full scale power...
Synchronization control for ultrafast laser parallel microdrilling system
Zhai, Zhongsheng; Kuang, Zheng; Ouyang, Jinlei; Liu, Dun; Perrie, Walter; Edwardson, Stuart P.; Dearden, Geoff
2014-11-01
Ultrafast lasers, emitting ultra-short pulses of light, generally of the order of femtoseconds to ten picoseconds, are widely used in micro-processing with the advantage of very little thermal damage. Parallel micro-processing is seen significant developments in laser fabrication, thanking to the spatial light modulator (SLM) which can concert single beam to multiple beams through computer generate holograms (CGHs). However, without synchronization control, on the conditions of changing different holograms or processing on large area beyond scanning galvo's ability, the fabrication will be interrupted constantly for changing holograms and moving the stages. Therefore, synchronization control is very important to improve the convenience and application of parallel micro-processing. A synchronization control method, carried out through two application software: SAMLight (or WaveRunner) and Labview, is presented in this paper. SAMLight is used to control the laser and the scanning galvo to implement microprocessing, and the developed program with Labview is used to control the SLM and motion stages. The synchronization signals, transmitted between the two software, are utilized by a National Instruments (NI) device USB-6008. Using optimal control methods, the synchronized system can easily and automatically accomplish complicated fabrications with minimum time. A multi-drilling application is provided to verify the affectivity of the synchronized control method. It uses multiple annular beams, generated by superimposing multi-beam CGH onto a diffractive axicon CGH, to drill multiple holes at one time, and it can automatically finish different patterns based on synchronization control. This drilling way is an optical trepanning and it avoids huge laser energy waste with attenuation. The multi-beam CGHs, generated by the Grating and Lens algorithm, are different for different patterns. The processing is over 200 times faster than traditional mechanical trepanning
A distributed timing system for synchronizing control and data correlation
International Nuclear Information System (INIS)
Stettler, M.; Thuot, M.; Dalesio, L.R.; Cole, R.; Fite, C.; Slentz, G.; Warren, D.
1992-01-01
Synchronization is necessary in experimental physics machines to provide positive control over related events. The Ground Test Accelerator (GTA) timing system provides this function through a distributed control system, known as the Experimental Physics and Industrial Control System (EPICS). The EPICS timing system was designed to take advantage of a distributed architecture, and provides time stamping for synchronous data correlation as well as event control. The system has been successfully demonstrated on over a dozen controller nodes for operation and data analysis. The design of the hardware, software, and operational results are discussed. (author). 2 refs., 4 figs
Shape synchronization control for three-dimensional chaotic systems
International Nuclear Information System (INIS)
Huang, Yuanyuan; Wang, Yinhe; Chen, Haoguang; Zhang, Siying
2016-01-01
This paper aims to the three-dimensional continuous chaotic system and shape of the chaotic attractor by utilizing the basic theory of plane curves in classical differential geometry, the continuous controller is synthesized for the master–slave synchronization in shape. This means that the slave system can possess the same shape of state trajectory with the master system via the continuous controller. The continuous controller is composed of three sub-controllers, which respectively correspond to the master–slave synchronization in shape for the three projective curves of the chaotic attractor onto the three coordinate planes. Moreover, the proposed shape synchronization technique as well as application of control scheme to secure communication is also demonstrated in this paper, where numerical simulation results show the proposed control method works well.
Time Stamp Synchronization of PEFP Distributed Control Systems
International Nuclear Information System (INIS)
Song, Young Gi; An, Eun Mi; Kwon, Hyeok Jung; Cho, Yong Sub
2010-01-01
Proton Engineering Frontier Project (PEFP) proton linac consists of several types of control systems, such as soft Input Output Controllers (IOC) and embedded IOC based on Experimental Physics Industrial Control System (EPICS) for each subsection of PEFP facility. One of the important factors is that IOC's time clock is synchronized. The synchronized time and time stamp can be achieved with Network Time Protocol (NTP) and EPICS time stamp record without timing hardware. The requirement of the time accuracy of IOCs is less than 1 second. The main objective of this study is to configure a master clock and produce Process Variable (PV) time stamps using local CPU time synchronized from the master clock. The distributed control systems are attached on PEFP control network
Distributed Synchronization Control of Multiagent Systems With Unknown Nonlinearities.
Su, Shize; Lin, Zongli; Garcia, Alfredo
2016-01-01
This paper revisits the distributed adaptive control problem for synchronization of multiagent systems where the dynamics of the agents are nonlinear, nonidentical, unknown, and subject to external disturbances. Two communication topologies, represented, respectively, by a fixed strongly-connected directed graph and by a switching connected undirected graph, are considered. Under both of these communication topologies, we use distributed neural networks to approximate the uncertain dynamics. Decentralized adaptive control protocols are then constructed to solve the cooperative tracker problem, the problem of synchronization of all follower agents to a leader agent. In particular, we show that, under the proposed decentralized control protocols, the synchronization errors are ultimately bounded, and their ultimate bounds can be reduced arbitrarily by choosing the control parameter appropriately. Simulation study verifies the effectiveness of our proposed protocols.
Synchronization and Control of Linearly Coupled Singular Systems
Directory of Open Access Journals (Sweden)
Fang Qingxiang
2013-01-01
Full Text Available The synchronization and control problem of linearly coupled singular systems is investigated. The uncoupled dynamical behavior at each node is general and can be chaotic or, otherwise the coupling matrix is not assumed to be symmetrical. Some sufficient conditions for globally exponential synchronization are derived based on Lyapunov stability theory. These criteria, which are in terms of linear matrix inequality (LMI, indicate that the left and right eigenvectors corresponding to eigenvalue zero of the coupling matrix play key roles in the stability analysis of the synchronization manifold. The controllers are designed for state feedback control and pinning control, respectively. Finally, a numerical example is provided to illustrate the effectiveness of the proposed conditions.
Hierarchical-control-based output synchronization of coexisting attractor networks
International Nuclear Information System (INIS)
Yun-Zhong, Song; Yi-Fa, Tang
2010-01-01
This paper introduces the concept of hierarchical-control-based output synchronization of coexisting attractor networks. Within the new framework, each dynamic node is made passive at first utilizing intra-control around its own arena. Then each dynamic node is viewed as one agent, and on account of that, the solution of output synchronization of coexisting attractor networks is transformed into a multi-agent consensus problem, which is made possible by virtue of local interaction between individual neighbours; this distributed working way of coordination is coined as inter-control, which is only specified by the topological structure of the network. Provided that the network is connected and balanced, the output synchronization would come true naturally via synergy between intra and inter-control actions, where the Tightness is proved theoretically via convex composite Lyapunov functions. For completeness, several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme. (general)
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.
PID control for chaotic synchronization using particle swarm optimization
International Nuclear Information System (INIS)
Chang, W.-D.
2009-01-01
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.
Nonlinear control of permanent magnet synchronous motor driving a ...
African Journals Online (AJOL)
This paper presents a non-linear control of permanent magnet synchronous motor (PMSM) fed by a PWM voltage source inverter. To improve the performance of this control technique, the input-output linearization technique is proposed for a system driving a mechanical load with two masses. In order to ensure a steady ...
Hysteresis Control for a DC Connected Synchronous Generator
DEFF Research Database (Denmark)
Rasmussen, Tonny Wederberg; Evangelos, Dimarakis
2009-01-01
Abstract— for offshore wind farms the distance to the coast increases, therefore DC cables will have to be used. For a variable speed wind turbine a rectifier and a synchronous generator with a boost converter is used. As a new suggestion for control the generator speed hysteresis control...
Control of Synchronization Regimes in Networks of Mobile Interacting Agents
Perez-Diaz, Fernando; Zillmer, Ruediger; Groß, Roderich
2017-05-01
We investigate synchronization in a population of mobile pulse-coupled agents with a view towards implementations in swarm-robotics systems and mobile sensor networks. Previous theoretical approaches dealt with range and nearest-neighbor interactions. In the latter case, a synchronization-hindering regime for intermediate agent mobility is found. We investigate the robustness of this intermediate regime under practical scenarios. We show that synchronization in the intermediate regime can be predicted by means of a suitable metric of the phase response curve. Furthermore, we study more-realistic K -nearest-neighbor and cone-of-vision interactions, showing that it is possible to control the extent of the synchronization-hindering region by appropriately tuning the size of the neighborhood. To assess the effect of noise, we analyze the propagation of perturbations over the network and draw an analogy between the response in the hindering regime and stable chaos. Our findings reveal the conditions for the control of clock or activity synchronization of agents with intermediate mobility. In addition, the emergence of the intermediate regime is validated experimentally using a swarm of physical robots interacting with cone-of-vision interactions.
Synchronizing and controlling hyperchaos in complex Lorentz-Haken systems
International Nuclear Information System (INIS)
Fang Jinqing
1995-03-01
Synchronizing hyperchaos is realized by the drive-response relationship in the complex Lorentz-Haken system and its higher-order cascading systems for the first time. Controlling hyperchaos is achieved by the intermittent proportional feedback to all of the drive (master) system variables. The complex Lorentz-Haken system describes the detuned single-mode laser and is taken as a typical example of hyperchaotic synchronization to clarify our ideas and results. The ideas and concepts could be extended to some nonlinear dynamical systems and have prospects for potential applications, for example. to laser, electronics, plasma, cryptography, communication, chemical and biological systems and so on. (8 figs., 2 tabs.)
Sliding mode control for synchronous electric drives
Ryvkin, Sergey E
2011-01-01
This volume presents the theory of control systems with sliding mode applied to electrical motors and power converters. It demonstrates the methodology of control design and the original algorithms of control and observation. Practically all semiconductor devices are used in power converters, that feed electrical motors, as power switches. A switching mode offers myriad attractive, inherent properties from a control viewpoint, especially a sliding mode. Sliding mode control supplies high dynamics to systems, invariability of systems to changes of their parameters and of exterior loads in combi
Adaptive control and synchronization of a fractional-order chaotic ...
Indian Academy of Sciences (India)
tem based on the stability theory of fractional-order dynamic systems. The presented schemes, which contain only a single-state variable, are simple and flexible. Numerical simulations are used to demonstrate the feasibility of the presented methods. Keywords. Fractional order; adaptive scheme; control; synchronization.
Adaptive control and synchronization of a fractional-order chaotic ...
Indian Academy of Sciences (India)
journal of. April 2013 physics pp. 583–592. Adaptive control and synchronization of a fractional-order chaotic system. CHUNLAI LI1,∗ and YAONAN TONG2. 1College of Physics and Electronics; 2School of Information and Communication Engineering,. Hunan Institute of Science and Technology, Yueyang 414006, China.
Robust chaos synchronization using input-to-state stable control
Indian Academy of Sciences (India)
function vector satisfying the global Lipschitz condition with Lipschitz constant. Lg > 0. The system (5) is considered as a drive system. The synchronization problem of system (5) is considered by using the drive- response configuration. According to the drive-response concept, the controlled response system is given by.
Synchronization of general complex networks via adaptive control ...
Indian Academy of Sciences (India)
2014-03-07
Mar 7, 2014 ... networks with derivative coupling and time-delay coupling was investigated by adaptive control schemes [42]. However ... [41], the synchronization of complex dynamical networks with non-derivative coupling and derivative coupling .... For any symmetric positive definite matrix. M ∈ Rn×n and x,y ∈ Rn, ...
Facility-wide synchronization of standard FAIR equipment controllers
International Nuclear Information System (INIS)
Rauch, S.; Terpstra, W.; Panschow, W.; Thieme, M.; Prados, C.; Zweig, M.; Kreider, M.; Beck, D.; Bär, R.
2012-01-01
The standard equipment controller under development for the new FAIR accelerator facility is the Scalable Control Unit (SCU). It is designed to synchronize and control the actions of up to 12 purpose-built slave cards, connected in a proprietary crate by a parallel backplane. Inter-crate coordination and facility-wide synchronization are a core FAIR requirement and thus precise timing of SCU slave actions is of vital importance. The SCU consists primarily of two components, an x86 COM Express daughter board and a carrier board with an Altera Arria II GX FPGA, interconnected by PCI Express. The x86 receives configuration and set values with which it programs the real-time event-condition-action (ECA) unit in the FPGA. The ECA unit receives event messages via the timing network, which also synchronizes the clocks of all SCUs in the facility using White Rabbit. Matching events trigger actions on the SCU slave cards such as: ramping magnets, triggering kickers, etc. Timing requirements differ depending on the action taken. For softer real-time actions, an interrupt can be generated for complex processing on the x86. Alternatively, the FPGA can directly fire a pulse out a LEMO output or an immediate SCU bus operation. The delay and synchronization achievable in each case differs and this paper examines the timing performance of each to determine which approach is appropriate for the required actions. (author)
Damping torque analysis of VSC-based system utilizing power synchronization control
Fu, Q.; Du, W. J.; Zheng, K. Y.; Wang, H. F.
2017-05-01
Power synchronization control is a new control strategy of VSC-HVDC for connecting a weak power system. Different from the vector control method, this control method utilizes the internal synchronization mechanism in ac systems, in principle, similar to the operation of a synchronous machine. So that the parameters of controllers in power synchronization control will change the electromechanical oscillation modes and make an impact on the transient stability of power system. This paper present a mathematical model for small-signal stability analysis of VSC station used power synchronization control and analyse the impact of the dynamic interactions by calculating the contribution of the damping torque from the power synchronization control, besides, the parameters of controllers which correspond to damping torque and synchronous torque in the power synchronization control is defined respectively. At the end of the paper, an example power system is presented to demonstrate and validate the theoretical analysis and associated conclusions are made.
Control of partial synchronization in chaotic oscillators
Indian Academy of Sciences (India)
2015-02-07
Feb 7, 2015 ... and vice versa without loss of synchrony) keeping the other pairs of variables undisturbed in their pre-desired states of ... follow the dynamics of an external signal (periodic or chaotic) while keeping the coherent status of other variables ...... Selected Papers on Mathematical Trends in Control Theory (1964).
An approach of partial control design for system control and synchronization
International Nuclear Information System (INIS)
Hu Wuhua; Wang Jiang; Li Xiumin
2009-01-01
In this paper, a general approach of partial control design for system control and synchronization is proposed. It turns control problems into simpler ones by reducing their control variables. This is realized by utilizing the dynamical relations between variables, which are described by the dynamical relation matrix and the dependence-influence matrix. By adopting partial control theory, the presented approach provides a simple and general way to stabilize systems to their partial or whole equilibriums, or to synchronize systems with their partial or whole states. Further, based on this approach, the controllers can be simplified. Two examples of synchronizing chaotic systems are given to illustrate its effectiveness.
Li, Chengren; Lü, Ling; Zhao, Guannan; Li, Gang; Tian, Jing; Gu, Jiajia; Wang, Zhouyang
2017-05-01
We modify sliding mode control technique from the synchronization of a single dynamic system to the synchronization of complex network. Projective synchronization of uncertain scale-free network is investigated based on modified sliding mode control technique. Further, the sliding surfaces, the identification laws of uncertain parameters and the control inputs are designed, and the condition of realizing projective synchronization of uncertain scale-free network is obtained. Finally, the Logistic systems with chaotic behavior are taken as nodes to constitute the scale-free network and the synchronization target. The simulation results show that the synchronization mechanism is effective.
FPGA based, modular, configurable controller with fast synchronous optical network
Energy Technology Data Exchange (ETDEWEB)
Graczyk, R.; Pozniak, K.T.; Romaniuk, R.S. [Warsaw Univ. of Technology (Poland). Inst. of Electronic Systems
2006-07-01
The paper describes a configurable controller equipped with programmable VLSI FPGA circuit, universal expansion modules PMC, synchronous, optical, multi-gigabit links, commonly used industrial and computer communication interfaces, Ethernet 100TB, system of automatic initialization ACE etc. There are characterized the basic functional characteristics of the device. The possibilities of its usage in various work modes were presented. Realization of particular blocks of the device were discussed. Resulting, during the realization of this project, new hardware layer solutions were also characterized. (orig.)
FPGA based, modular, configurable controller with fast synchronous optical network
International Nuclear Information System (INIS)
Graczyk, R.; Pozniak, K.T.; Romaniuk, R.S.
2006-01-01
The paper describes a configurable controller equipped with programmable VLSI FPGA circuit, universal expansion modules PMC, synchronous, optical, multi-gigabit links, commonly used industrial and computer communication interfaces, Ethernet 100TB, system of automatic initialization ACE etc. There are characterized the basic functional characteristics of the device. The possibilities of its usage in various work modes were presented. Realization of particular blocks of the device were discussed. Resulting, during the realization of this project, new hardware layer solutions were also characterized. (orig.)
An Improved Adaptive Tracking Controller of Permanent Magnet Synchronous Motor
Directory of Open Access Journals (Sweden)
Tat-Bao-Thien Nguyen
2014-01-01
Full Text Available This paper proposes a new adaptive fuzzy neural control to suppress chaos and also to achieve the speed tracking control in a permanent magnet synchronous motor (PMSM drive system with unknown parameters and uncertainties. The control scheme consists of fuzzy neural and compensatory controllers. The fuzzy neural controller with online parameter tuning is used to estimate the unknown nonlinear models and construct linearization feedback control law, while the compensatory controller is employed to attenuate the estimation error effects of the fuzzy neural network and ensure the robustness of the controlled system. Moreover, due to improvement in controller design, the singularity problem is surely avoided. Finally, numerical simulations are carried out to demonstrate that the proposed control scheme can successfully remove chaotic oscillations and allow the speed to follow the desired trajectory in a chaotic PMSM despite the existence of unknown models and uncertainties.
International Nuclear Information System (INIS)
Wen Guilin; Wang Qingguo; Lin Chong; Han Xu; Li Guangyao
2006-01-01
Synchronization under output feedback control with multiple random time delays is studied, using the paradigm in nonlinear physics-Chua's circuit. Compared with other synchronization control methods, output feedback control with multiple random delay is superior for a realistic synchronization application to secure communications. Sufficient condition for global stability of delay-dependent synchronization is established based on the LMI technique. Numerical simulations fully support the analytical approach, in spite of the random delays
Fuzzy adaptive speed control of a permanent magnet synchronous motor
Choi, Han Ho; Jung, Jin-Woo; Kim, Rae-Young
2012-05-01
A fuzzy adaptive speed controller is proposed for a permanent magnet synchronous motor (PMSM). The proposed fuzzy adaptive speed regulator is insensitive to model parameter and load torque variations because it does not need any accurate knowledge about the motor parameter and load torque values. The stability of the proposed control system is also proven. The proposed adaptive speed regulator system is implemented by using a TMS320F28335 floating point DSP. Simulation and experimental results are presented to verify the effectiveness of the proposed fuzzy adaptive speed controller under uncertainties such as motor parameter and load torque variations using a prototype PMSM drive system.
Stability and synchronization control of stochastic neural networks
Zhou, Wuneng; Zhou, Liuwei; Tong, Dongbing
2016-01-01
This book reports on the latest findings in the study of Stochastic Neural Networks (SNN). The book collects the novel model of the disturbance driven by Levy process, the research method of M-matrix, and the adaptive control method of the SNN in the context of stability and synchronization control. The book will be of interest to university researchers, graduate students in control science and engineering and neural networks who wish to learn the core principles, methods, algorithms and applications of SNN.
Persis, Claudio De; Jayawardhana, Bayu
2012-01-01
The role of internal model principle is investigated in this paper in the context of collective synchronization and formation control problems. In the collective synchronization problem for nonlinear systems, we propose distributed control laws for passive systems which synchronize to the solution
A new criterion for chaos and hyperchaos synchronization using linear feedback control
International Nuclear Information System (INIS)
Wang Faqiang; Liu Chongxin
2006-01-01
Based on the characteristic of the chaotic or hyperchaotic system and linear feedback control method, synchronization of the two identical chaotic or hyperchaotic systems with different initial conditions is studied. The range of the control parameter for synchronization is derived. Simulation results are provided to show the effectiveness of the proposed synchronization method
Impulsive control of permanent magnet synchronous motors with parameters uncertainties
International Nuclear Information System (INIS)
Li Dong; Zhang Xiaohong; Wang Shilong; Yan Dan; Wang Hui
2008-01-01
The permanent magnet synchronous motors (PMSMs) may have chaotic behaviours for the uncertain values of parameters or under certain working conditions, which threatens the secure and stable operation of motor-driven. It is important to study methods of controlling or suppressing chaos in PMSMs. In this paper, robust stabilities of PMSM with parameter uncertainties are investigated. After the uncertain matrices which represent the variable system parameters are formulated through matrix analysis, a novel asymptotical stability criterion is established. Some illustrated examples are also given to show the effectiveness of the obtained results
International Nuclear Information System (INIS)
Cui Baotong; Lou Xuyang
2009-01-01
In this paper, a new method to synchronize two identical chaotic recurrent neural networks is proposed. Using the drive-response concept, a nonlinear feedback control law is derived to achieve the state synchronization of the two identical chaotic neural networks. Furthermore, based on the Lyapunov method, a delay independent sufficient synchronization condition in terms of linear matrix inequality (LMI) is obtained. A numerical example with graphical illustrations is given to illuminate the presented synchronization scheme
Anti-synchronizing control for supermarket refrigeration systems
DEFF Research Database (Denmark)
Larsen, Lars Finn Sloth; Thybo, Claus; Wisniewski, Rafal
2007-01-01
Abstract—A supermarket refrigeration system is a hybrid system with switched nonlinear dynamics and discrete-valued input variables such as opening/closing of valves and start/stop of compressors. Practical and simulation studies have shown that the use of distributed hysteresis controllers...... to operate the valves leads to synchronization, meaning that the opening and closing actions of the valves coincide. Consequently, the compressor periodically has to work hard resulting in low efficiency, inferior control performance and a high wear on the compressor. In this paper we propose two control...... schemes of low complexity for desynchronizing the valve operations while improving performance. Simulation results indicate the potential increase in efficiency and reduction in wear comparing with traditional control schemes....
Confusion Control in Generalized Petri Nets Using Synchronized Events
Directory of Open Access Journals (Sweden)
Xiaoliang Chen
2015-01-01
Full Text Available The loss of conflicting information in a Petri net (PN, usually called confusions, leads to incomplete and faulty system behavior. Confusions, as an unfortunate phenomenon in discrete event systems modeled with Petri nets, are caused by the frequent interlacement of conflicting and concurrent transitions. In this paper, confusions are defined and investigated in bounded generalized PNs. A reasonable control strategy for conflicts and confusions in a PN is formulated by proposing elementary conflict resolution sequences (ECRSs and a class of local synchronized Petri nets (LSPNs. Two control algorithms are reported to control the appeared confusions by generating a series of external events. Finally, an example of confusion analysis and control in an automated manufacturing system is presented.
Collaborative simulation method with spatiotemporal synchronization process control
Zou, Yisheng; Ding, Guofu; Zhang, Weihua; Zhang, Jian; Qin, Shengfeng; Tan, John Kian
2016-10-01
When designing a complex mechatronics system, such as high speed trains, it is relatively difficult to effectively simulate the entire system's dynamic behaviors because it involves multi-disciplinary subsystems. Currently,a most practical approach for multi-disciplinary simulation is interface based coupling simulation method, but it faces a twofold challenge: spatial and time unsynchronizations among multi-directional coupling simulation of subsystems. A new collaborative simulation method with spatiotemporal synchronization process control is proposed for coupling simulating a given complex mechatronics system across multiple subsystems on different platforms. The method consists of 1) a coupler-based coupling mechanisms to define the interfacing and interaction mechanisms among subsystems, and 2) a simulation process control algorithm to realize the coupling simulation in a spatiotemporal synchronized manner. The test results from a case study show that the proposed method 1) can certainly be used to simulate the sub-systems interactions under different simulation conditions in an engineering system, and 2) effectively supports multi-directional coupling simulation among multi-disciplinary subsystems. This method has been successfully applied in China high speed train design and development processes, demonstrating that it can be applied in a wide range of engineering systems design and simulation with improved efficiency and effectiveness.
Synchronously Driven Power Converter Controller Solution for MedAustron
Šepetavc, Luka; Tavčar, Rok; Moser, Roland; Gutleber, Johannes
2011-01-01
MedAustron is an ion beam cancer therapy and research centre currently under construction in Wiener Neustadt, Austria. This facility features a synchrotron particle accelerator for light ions. Cosylab is closely working together with MedAustron on the development of a power converter controller (PCC) for the 260 deployed power converters – power supplies. Power converters deliver power to magnets used for focusing and steering particle beams. We have designed and developed software and hardware which allows integration of different types of power converters into MedAustron's control system (MACS). PCC's role is to synchronously control and monitor connected power converters. Custom real-time fibre optics link and modular front end devices have been designed for this purpose. Modular front end devices make it possible to interface with almost any type of power converter – with or without built in regulation logic. We implemented realtime mechanisms and a dedicated real-time fibre link to ...
Adaptive chaos control and synchronization in only locally Lipschitz systems
International Nuclear Information System (INIS)
Lin Wei
2008-01-01
In the existing results on chaos control and synchronization based on the adaptive controlling technique (ACT), a uniform Lipschitz condition on a given dynamical system is always assumed in advance. However, without this uniform Lipschitz condition, the ACT might be failed in both theoretical analysis and in numerical experiment. This Letter shows how to utilize the ACT to get a rigorous control for the system which is not uniformly Lipschitz but only locally Lipschitz, and even for the system which has unbounded trajectories. In fact, the ACT is proved to possess some limitation, which is actually induced by the nonlinear degree of the original system. Consequently, a piecewise ACT is proposed so as to improve the performance of the existing techniques
Synchronous temperature rate control for refrigeration with reduced energy consumption
Gomes, Alberto Regio; Keres, Stephen L.; Kuehl, Steven J.; Litch, Andrew D.; Richmond, Peter J.; Wu, Guolian
2015-09-22
Methods of operation for refrigerator appliance configurations with a controller, a condenser, at least one evaporator, a compressor, and two refrigeration compartments. The configuration may be equipped with a variable-speed or variable-capacity compressor, variable speed evaporator or compartment fans, a damper, and/or a dual-temperature evaporator with a valve system to control flow of refrigerant through one or more pressure reduction devices. The methods may include synchronizing alternating cycles of cooling each compartment to a temperature approximately equal to the compartment set point temperature by operation of the compressor, fans, damper and/or valve system. The methods may also include controlling the cooling rate in one or both compartments. Refrigeration compartment cooling may begin at an interval before or after when the freezer compartment reaches its lower threshold temperature. Freezer compartment cooling may begin at an interval before or after when the freezer compartment reaches its upper threshold temperature.
Synchronous temperature rate control for refrigeration with reduced energy consumption
Energy Technology Data Exchange (ETDEWEB)
Gomes, Alberto Regio; Keres, Stephen L.; Kuehl, Steven J.; Litch, Andrew D.; Richmond, Peter J.; Wu, Guolian
2017-11-07
Methods of operation for refrigerator appliance configurations with a controller, a condenser, at least one evaporator, a compressor, and two refrigeration compartments. The configuration may be equipped with a variable-speed or variable-capacity compressor, variable speed evaporator or compartment fans, a damper, and/or a dual-temperature evaporator with a valve system to control flow of refrigerant through one or more pressure reduction devices. The methods may include synchronizing alternating cycles of cooling each compartment to a temperature approximately equal to the compartment set point temperature by operation of the compressor, fans, damper and/or valve system. The methods may also include controlling the cooling rate in one or both compartments. Refrigeration compartment cooling may begin at an interval before or after when the freezer compartment reaches its lower threshold temperature. Freezer compartment cooling may begin at an interval before or after when the freezer compartment reaches its upper threshold temperature.
Fuzzy Impulsive Control of Permanent Magnet Synchronous Motors
International Nuclear Information System (INIS)
Dong, Li; Shi-Long, Wang; Xiao-Hong, Zhang; Dan, Yang; Hui, Wang
2008-01-01
The permanent magnet synchronous motors (PMSMs) may experience chaotic behaviours with systemic parameters falling into a certain area or under certain working conditions, which threaten the secure and stable operation of motor-driven. Hence, it is important to study the methods of controlling or suppressing chaos in PMSMs. In this work, the Takagi–Sugeno (T-S) fuzzy impulsive control model for PMSMs is established via the T-S modelling methodology and impulsive technology. Based on the new model, the control conditions of asymptotical stability and exponential stability for PMSMs have been derived by the Lyapunov method. Finally, an illustrated example is also given to show the effectiveness of the obtained results
Application of synchronous grid-connected controller in the wind-solar-storage micro grid
Li, Hua; Ren, Yongfeng; Li, Le; Luo, Zhenpeng
2016-01-01
Recently, there has been an increasing interest in using distributed generators (DG) not only to inject power into the grid, but also to enhance the power quality. In this study, a space voltage pulse width modulation (SVPWM) control method is proposed for a synchronous grid-connected controller in a wind-solar-storage micro grid. This method is based on the appropriate topology of the synchronous controller. The wind-solar-storage micro grid is controlled to reconnect to the grid synchronous...
The synchronization of loosely coupled motion control systems
Energy Technology Data Exchange (ETDEWEB)
Tuominen, P. [VTT Automation, Tampere (Finland). Machine Automation
1996-12-31
The aim of this thesis is to create an easily implemented, effective, dynamically schedulable flow control method, and to show how the methods introduced can be analysed using fixed priority scheduling. One of the most important problems in a distributed system is the delay and variation of it (the jitter) caused by a serial based network, especially when media load is relatively high. This thesis has looked for possibilities to implement a deterministic motion control system which can also operate with high media loads. The problem of end-to-end delay in distributed control systems has been addressed. The most promising ones are based on the two window concept, where critical messages are transmitted in the statically scheduled part of window while other, non-critical messages are transmitted in the remaining part. The concept of the chained link is introduced and it is shown how the latency time of a certain set of messages can be controlled. This thesis has introduced the detailed characteristics of this easy-to-assemble chain which is simpler than time or sync-message based methods used commercially. One benefit is that only those nodes needing synchronization must support synchronization tasks. Other nodes are exempt from supporting unnecessary functions, making system programming easier. The chain can be scheduled dynamically as one long message. The concept of a CAN based producer-consumer method, a statical scheduling method which can be used with a bus-master has been introduced. A hydraulic mobile is used as a practical example for analysing and comparing the introduced distribution and flow control methods
Flux-weakening control methods for hybrid excitation synchronous motor
Directory of Open Access Journals (Sweden)
Mingming Huang
2015-09-01
Full Text Available The hybrid excitation synchronous motor (HESM, which aim at combining the advantages of permanent magnet motor and wound excitation motor, have the characteristics of low-speed high-torque hill climbing and wide speed range. Firstly, a new kind of HESM is presented in the paper, and its structure and mathematical model are illustrated. Then, based on a space voltage vector control, a novel flux-weakening method for speed adjustment in the high speed region is presented. The unique feature of the proposed control method is that the HESM driving system keeps the q-axis back-EMF components invariable during the flux-weakening operation process. Moreover, a copper loss minimization algorithm is adopted to reduce the copper loss of the HESM in the high speed region. Lastly, the proposed method is validated by the simulation and the experimental results.
Programmable logic controller based synchronous motor excitation system
Directory of Open Access Journals (Sweden)
Janda Žarko
2011-01-01
Full Text Available This paper presents a 3.5 MW synchronous motor excitation system reconstruction. In the proposed solution programmable logic controller is used to control motor, which drives the turbo compressor. Comparing to some other solutions that are used in similar situations, the proposed solution is superior due to its flexibility and usage of mass-production hardware. Moreover, the implementation of PLC enables easy integration of the excitation system with the other technological processes in the plant as well as in the voltage regulation of 'smart grid' system. Also, implementation of various optimization algorithms can be done comfortably and it does not require additional investment in hardware. Some experimental results that depict excitation current during motor start-up, as well as, measured static characteristics of the motor, were presented.
Synchronization control for large-scale network systems
Wu, Yuanqing; Su, Hongye; Shi, Peng; Wu, Zheng-Guang
2017-01-01
This book provides recent advances in analysis and synthesis of Large-scale network systems (LSNSs) with sampled-data communication and non-identical nodes. In its first chapter of the book presents an introduction to Synchronization of LSNSs and Algebraic Graph Theory as well as an overview of recent developments of LSNSs with sampled data control or output regulation control. The main text of the book is organized into two main parts - Part I: LSNSs with sampled-data communication and Part II: LSNSs with non-identical nodes. This monograph provides up-to-date advances and some recent developments in the analysis and synthesis issues for LSNSs with sampled-data communication and non-identical nodes. It describes the constructions of the adaptive reference generators in the first stage and the robust regulators in the second stage. Examples are presented to show the effectiveness of the proposed design techniques.
Virtual synchronous-machine control of voltage-source converters in a low-voltage microgrid
Hogan, Diarmaid J.; Gonzalez-Espin, F.; Hayes, John G.; Lightbody, Gordon; Albiol-Tendillo, L.; Foley, Ray
2016-01-01
In order to facilitate the further integration of distributed renewable generation into existing power systems, enhanced control schemes for grid-tied power electronic converters are necessary to ensure non-synchronous power sources can provide power and support to the grid. The virtual-synchronous-machine concept proposes the use of control schemes to enable static generators to operate with the dynamics of rotating synchronous generators. In this paper, a control scheme is presented based o...
Pratiksha Shingade; Arati Dalavi
2014-01-01
The co-ordination and synchronization control of motion of multiple motors is a challenging problem, since the synchronization of each individual motor can be influenced by many factors. This paper presents the concept and implementation of a scheme that uses a real time control approach to realize drive synchronization of the multiple motors. The basic principle of the control is the speed of both master and slave are measured and compared in such a way to get speed synchroni...
Chaos synchronization in RCL-shunted Josephson junction via active control
International Nuclear Information System (INIS)
Ucar, Ahmet; Lonngren, Karl E.; Bai, E.-W.
2007-01-01
This paper investigates the synchronization of coupled RCL-shunted Josephson junction that is of interest in high-frequency applications. A nonlinear controller is developed in order to achieve the desired behavior. The synchronization is obtained using the slave-master technique and the controller ensures that the states of the controlled chaotic slave system exponentially synchronize with the state of the master system. Numerical simulations are illustrate and verify the proposed method
Adaptive synchronization of Genesio-Tesi chaotic system via a novel feedback control
International Nuclear Information System (INIS)
Park, Ju H.; Lee, S.M.; Kwon, O.M.
2007-01-01
The Letter addresses control problem for adaptive synchronization of the Genesio-Tesi chaotic systems with three uncertain parameters. A new control scheme is proposed to make the states of two Genesio-Tesi systems asymptotically synchronized. Based on the Lyapunov method and linear matrix inequality (LMI) framework, an existence criterion for the control law is derived in terms of LMIs. A numerical simulation is illustrated to show the effectiveness of the proposed chaos synchronization scheme
Synchronization in a Random Length Ring Network for SDN-Controlled Optical TDM Switching
DEFF Research Database (Denmark)
Kamchevska, Valerija; Cristofori, Valentina; Da Ros, Francesco
2016-01-01
In this paper we focus on optical time division multiplexed (TDM) switching and its main distinguishing characteristics compared with other optical subwavelength switching technologies. We review and discuss in detail the synchronization requirements that allow for proper switching operation....... In addition, we propose a novel synchronization algorithm that enables automatic synchronization of software defined networking controlled all-optical TDM switching nodes connected in a ring network. Besides providing synchronization, the algorithm also can facilitate dynamic slot size change and failure...... multiplexing transmission and switching of data bursts when using the proposed algorithm to provide synchronization....
Synchronization of Droop-Controlled Microgrids with Distributed Rotational and Electronic Generation
Schiffer, JF; Goldin, D; Raisch, J; Sezi, T
2013-01-01
We consider the problem of frequency synchronization and power sharing in a lossy droop-controlled autonomous microgrid with distributed rotational and electronic generation (MDREG). At first, we establish equivalence of the dynamics of a regulated synchronous generator and a droop-controlled inverter with low pass filter. We then give a necessary and sufficient condition for local synchronization of the microgrid by using ideas from graph theory and second order consensus algorithms. In addi...
International Nuclear Information System (INIS)
Chen Yun; Wu Xiaofeng; Liu Zhong
2009-01-01
This paper studies global synchronization of non-autonomous chaotic electro-mechanical gyrostat systems via variable substitution control. A master-slave non-autonomous synchronization scheme with variable substitution control is mathematically presented. Based on the scheme, some sufficient algebraic criteria for global chaos synchronization of master and slave electro-mechanical gyrostat systems via various single-variable coupling are derived. The effectiveness of the obtained criteria is numerically illustrated by the examples.
International Nuclear Information System (INIS)
Park, Ju H.
2007-01-01
The paper addresses control problem for the modified projective synchronization of the Genesio-Tesi chaotic systems with three uncertain parameters. An adaptive control law is derived to make the states of two identical Genesio-Tesi systems asymptotically synchronized up to specific ratios. The stability analysis in the paper is proved using a well-known Lyapunov stability theory. A numerical simulation is presented to show the effectiveness of the proposed chaos synchronization scheme
DEFF Research Database (Denmark)
Wang, Yun; Wu, Qiuwei; Yang, Rong
2018-01-01
This paper proposes an H∞ damping controller for the doubly-fed induction generator (DFIG) based wind farm (WF) to mitigate sub-synchronous control interactions (SSCI) with series capacitor compensated lines. A multi-input multi-output (MIMO) uncertain state-space model is developed to reflect...
Wen, Shiping; Zeng, Zhigang; Chen, Michael Z Q; Huang, Tingwen
2017-10-01
This paper addresses the issue of synchronization of switched delayed neural networks with communication delays via event-triggered control. For synchronizing coupled switched neural networks, we propose a novel event-triggered control law which could greatly reduce the number of control updates for synchronization tasks of coupled switched neural networks involving embedded microprocessors with limited on-board resources. The control signals are driven by properly defined events, which depend on the measurement errors and current-sampled states. By using a delay system method, a novel model of synchronization error system with delays is proposed with the communication delays and event-triggered control in the unified framework for coupled switched neural networks. The criteria are derived for the event-triggered synchronization analysis and control synthesis of switched neural networks via the Lyapunov-Krasovskii functional method and free weighting matrix approach. A numerical example is elaborated on to illustrate the effectiveness of the derived results.
Pulsed-linac synchronization using an embedded micro-controller
International Nuclear Information System (INIS)
Craig, S.R.; Alexander, S.B.; West, R.J.; Simpson, M.P.
1992-01-01
A Master Timing Generator (MTG) was developed using a single Motorola MC68332 embedded micro-controller. The MTG produces electrical synchronization pulses that coordinate the action of all pulsed subsystems and the acquisition of pulsed data. Pulse width and delay-offset of each of the 13 output channels can be changed on-line. The MTG is interfaced with a GE Series-Six Programmable Logic Controller (PLC), which coordinates overall control of the IMPELA linac. Serial communications are used between the PLC and the MTG. The PLC needs only to transmit data to define the pulse repetition rate, the beam pulse width, and the subsystems that should be active. The MTG determines the widths and relative delays required to achieve the requested beam pulse-width. Changes in width and repetition rate are effected using a smooth ramp to avoid power-demand transients. All MTG timing requirements are met with the current implementation, having the following characteristics: 1 Hz ≤ repetition rate ≤ 500 Hz with ±1% resolution, 12 μs ≤ width ≤ 1000 μs in 1 μs steps, and a delay-offset range of 4.5 ms in 1 μs steps. (Author) (4 figs., 5 refs.)
Synchronization of Different Fractional Order Time-Delay Chaotic Systems Using Active Control
Directory of Open Access Journals (Sweden)
Jianeng Tang
2014-01-01
Full Text Available Chaos synchronization of different fractional order time-delay chaotic systems is considered. Based on the Laplace transform theory, the conditions for achieving synchronization of different fractional order time-delay chaotic systems are analyzed by use of active control technique. Then numerical simulations are provided to verify the effectiveness and feasibility of the developed method. At last, effects of the fraction order and the time delay on synchronization are further researched.
International Nuclear Information System (INIS)
Wang Jing; Gao Jinfeng; Ma Xikui
2007-01-01
This Letter presents a novel cross active backstepping design method for synchronization control of cross-strict feedback hyperchaotic system, in which the ordinary backstepping design is unavailable. The proposed control method, combining backstepping design and active control approach, extends the application of backstepping technique in chaos control. Based on this method, different combinations of controllers can be designed to meet the needs of different applications. The proposed method is applied to achieve chaos synchronization of two identical cross-strict feedback hyperchaotic systems. Also it is used to implement synchronization between cross-strict feedback hyperchaotic system and Roessler hyperchaotic system. Numerical examples illustrate the validity of the control method
Synchronization of chaos in RCL-shunted Josephson junction using a simple adaptive controller
International Nuclear Information System (INIS)
Guo, R; Vincent, U E; Idowu, B A
2009-01-01
In this paper, a simple adaptive control is proposed for the synchronization of chaotic dynamics of resistive-capacitive-inductive-shunted Josephson junctions (RCLSJ). The synchronization problem is investigated based on a drive-response system configuration consisting of two identical RCLSJ with and without identical system parameters. In addition, the synchronization when the system parameters are unknown is considered based on adaptive parameter control estimation. Sufficient conditions for global asymptotic synchronization are given and numerical simulations are employed to demonstrate the efficiency of the adaptive control scheme. In the presence of noise, we also show that the synchronization is robust and discuss the implication of our adaptive control technique in rapid single flux quantum (RSFQ) devices.
Delayed feedback control of bursting synchronization in a scale-free neuronal network.
Batista, C A S; Lopes, S R; Viana, R L; Batista, A M
2010-01-01
Several neurological diseases (e.g. essential tremor and Parkinson's disease) are related to pathologically enhanced synchronization of bursting neurons. Suppression of these synchronized rhythms has potential implications in electrical deep-brain stimulation research. We consider a simplified model of a neuronal network where the local dynamics presents a bursting timescale, and the connection architecture displays the scale-free property (power-law distribution of connectivity). The networks exhibit collective oscillations in the form of synchronized bursting rhythms, without affecting the fast timescale dynamics. We investigate the suppression of these synchronized oscillations using a feedback control in the form of a time-delayed signal. We located domains of bursting synchronization suppression in terms of perturbation strength and time delay, and present computational evidence that synchronization suppression is easier in scale-free networks than in the more commonly studied global (mean-field) networks.
Zhou, Peipei; Cai, Shuiming; Jiang, Shengqin; Liu, Zengrong
2018-02-01
In this paper, the problem of exponential cluster synchronization for a class of directed community networks is investigated via adaptive nonperiodically intermittent pinning control. By constructing a novel piecewise continuous Lyapunov function, some sufficient conditions to guarantee globally exponential cluster synchronization are derived. It is noted that the derived cluster synchronization criteria rely on the control rates, but not the control widths or the control periods, which facilitates the choice of the control periods in practical applications. A numerical example is finally presented to show the effectiveness of the obtained theoretical results.
International Nuclear Information System (INIS)
Deng Bin; Wang Jiang; Fei Xiangyang
2006-01-01
Backstepping design is a recursive procedure that combines the choice of a Lyapunov function with the design of a controller. In this paper, the backstepping control is used to synchronize two coupled chaotic neurons in external electrical stimulation. The coupled model is based on the nonlinear cable model and only one state variable can be controlled in practice. The backstepping design needs only one controller to synchronize two chaotic systems and it can be applied to a variety of chaotic systems whether they contain external excitation or not, so the two coupled chaotic neurons in external electrical stimulation can be synchronized perfectly by backstepping control. Numerical simulations demonstrate the effectiveness of this design
Exponential synchronization of the Genesio-Tesi chaotic system via a novel feedback control
International Nuclear Information System (INIS)
Park, Ju H
2007-01-01
A novel feedback control scheme is proposed for exponential synchronization of the Genesio-Tesi chaotic system. The feedback controller consists of two parts: a linear dynamic control law and a nonlinear control one. For exponential synchronization between the drive and response Genesio-Tesi systems, the Lyapunov stability analysis is used. Then an existence criterion for the stabilizing controller is presented in terms of linear matrix inequalities (LMIs). The LMIs can be solved easily by various convex optimization algorithms. Finally, a numerical simulation is illustrated to show the effectiveness of the proposed chaos synchronization scheme
Energy Technology Data Exchange (ETDEWEB)
Xu Yuhua [College of Information Science and Technology, Donghua University, Shanghai 201620 (China) and Department of Maths, Yunyang Teacher' s College, Hubei 442000 (China)], E-mail: yuhuaxu2004@163.com; Zhou Wuneng [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)], E-mail: wnzhou@163.com; Fang Jianan [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)
2009-11-15
This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.
Radwan, A.G.
2013-03-13
This paper discusses the continuous effect of the fractional order parameter of the Lü system where the system response starts stable, passing by chaotic behavior then reaching periodic response as the fractional-order increases. In addition, this paper presents the concept of synchronization of different fractional order chaotic systems using active control technique. Four different synchronization cases are introduced based on the switching parameters. Also, the static and dynamic synchronizations can be obtained when the switching parameters are functions of time. The nonstandard finite difference method is used for the numerical solution of the fractional order master and slave systems. Many numeric simulations are presented to validate the concept for different fractional order parameters.
Introducing state-trajectory control for the synchronous interleaved boost converter
DEFF Research Database (Denmark)
Peña-Alzola, Rafael; Ksiazek, Peter; Ordonez, Martin
2015-01-01
Synchronous interleaved boost converters (SIBCs) result in lower ripple currents and bidirectional power flow. The boost topology has a non-minimum phase characteristic, producing instability problems when a large bandwidth is required. Linear controllers inherently limit the boost controller...
DEFF Research Database (Denmark)
Swierczynski, Dariusz; Kazmierkowski, Marian P.; Blaabjerg, Frede
2002-01-01
DSP Based Direct Torque Control of Permanent Magnet Synchronous Motor (PMSM) using Space Vector Modulation (DTC-SVM)......DSP Based Direct Torque Control of Permanent Magnet Synchronous Motor (PMSM) using Space Vector Modulation (DTC-SVM)...
Synchronization of delayed complex networks via intermittent control with non-period
Liang, Yi; Qi, Xiaolong; Wei, Qiang
2018-02-01
In this paper, a pinning synchronization scheme of nonlinear coupled complex networks is investigated via non-periodically intermittent control method, in which dynamical system is delayed nonlinear system, and its coupling matrices can be nonsymmetric. In the case that control ratio of control width to total time width is equal in any time interval, the control scheme is studied, and some sufficient conditions are given to ensure global exponential synchronization. Furthermore, two main corollaries are derived. At last, numerical simulations show effectiveness of the synchronization scheme.
International Nuclear Information System (INIS)
Aguila-Camacho, Norelys; Duarte-Mermoud, Manuel A.; Delgado-Aguilera, Efredy
2016-01-01
This paper analyzes the synchronization of two fractional Lorenz systems in two cases: the first one considering fractional Lorenz systems with unknown parameters, and the second one considering known upper bounds on some of the fractional Lorenz systems parameters. The proposed control strategies use a reduced number of control signals and control parameters, employing mild assumptions. The stability of the synchronization errors is analytically demonstrated in all cases, and the convergence to zero of the synchronization errors is analytically proved in the case when the upper bounds on some system parameters are assumed to be known. Simulation studies are presented, which allows verifying the effectiveness of the proposed control strategies.
Li, Xiaodi; Rakkiyappan, R.
2013-06-01
This paper considers the chaotic synchronization problem of neural networks with time-varying and distributed delays using impulsive control method. By utilizing the stability theory for impulsive functional differential equations, several impulsive control laws are derived to guarantee the exponential synchronization of neural networks with time-varying and distributed delays. It is shown that chaotic synchronization of the networks is heavily dependent on the designed impulsive controllers. Moreover, these conditions are expressed in terms of LMI and can be easily checked by MATLAB LMI toolbox. Finally, a numerical example and its simulation are given to show the effectiveness and advantage of the proposed control schemes.
Directory of Open Access Journals (Sweden)
Jan Vittek
2004-01-01
Full Text Available Closed-loop position control of mechanisms directly driven by linear synchronous motors with permanent magnets is presented. The control strategy is based on forced dynamic control, which is a form of feedback linearisation, yielding a non-liner multivariable control law to obtain a prescribed linear speed dynamics together with the vector control condition of mutal orthogonality between the stator current and magnetic flux vectors (assuming perfect estimates of the plant parameters. Outer position control loop is closed via simple feedback with proportional gain. Simulations of the design control sysstem, including the drive with power electronic switching, predict the intended drive performance.
International Nuclear Information System (INIS)
Iqbal, Muhammad; Rehan, Muhammad; Hong, Keum-Shik; Khaliq, Abdul; Saeed-ur-Rehman
2015-01-01
This paper addresses the design of adaptive feedback controllers for two problems (namely, stabilization and synchronization) of chaotic systems with unknown parameters by considering input saturation constraints. A novel generalized sector condition is developed to deal with the saturation nonlinearities for synthesizing the nonlinear and the adaptive controllers for the stabilization and synchronization control objectives. By application of the proposed sector condition and rigorous regional stability analysis, control and adaptation laws are formulated to guarantee local stabilization of a nonlinear system under actuator saturation. Further, simple control and adaptation laws are developed to synchronize two chaotic systems under uncertain parameters and input saturation nonlinearity. Numerical simulation results for Rössler and FitzHugh–Nagumo models are provided to demonstrate the effectiveness of the proposed adaptive stabilization and synchronization control methodologies
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 k p , k i , k d 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.
Synchronization of FitzHugh-Nagumo neurons in external electrical stimulation via nonlinear control
International Nuclear Information System (INIS)
Wang Jiang; Zhang Ting; Deng Bin
2007-01-01
Synchronization of FitzHugh-Nagumo neural system under external electrical stimulation via the nonlinear control is investigated in this paper. Firstly, the different dynamical behavior of the nonlinear cable model based on the FitzHugh-Nagumo model responding to various external electrical stimulations is studied. Next, using the result of the analysis, a nonlinear feedback linearization control scheme and an adaptive control strategy are designed to synchronization two neurons. Computer simulations are provided to verify the efficiency of the designed synchronization schemes
The control system of synchronous movement of the gantry crane supports
Odnokopylov, I. G.; Gneushev, V. V.; Galtseva, O. V.; Natalinova, N. M.; Li, J.; Serebryakov, D. I.
2017-01-01
The paper presents study findings on synchronization of the gantry crane support movement. Asynchrony moving speed bearings may lead to an emergency mode at the natural rate of deformed metal structure alignment. The use of separate control of asynchronous motors with the vector control method allows synchronizing the movement speed of crane supports and achieving a balance between the motors. Simulation results of various control systems are described. Recommendations regarding the system further application are given.
Peng, Zhouhua; Wang, Dan; Zhang, Hongwei; Sun, Gang
2014-08-01
This paper addresses the leader-follower synchronization problem of uncertain dynamical multiagent systems with nonlinear dynamics. Distributed adaptive synchronization controllers are proposed based on the state information of neighboring agents. The control design is developed for both undirected and directed communication topologies without requiring the accurate model of each agent. This result is further extended to the output feedback case where a neighborhood observer is proposed based on relative output information of neighboring agents. Then, distributed observer-based synchronization controllers are derived and a parameter-dependent Riccati inequality is employed to prove the stability. This design has a favorable decouple property between the observer and the controller designs for nonlinear multiagent systems. For both cases, the developed controllers guarantee that the state of each agent synchronizes to that of the leader with bounded residual errors. Two illustrative examples validate the efficacy of the proposed methods.
Directory of Open Access Journals (Sweden)
Zengyun Wang
2013-01-01
Full Text Available This paper investigates the problem of synchronization for two different stochastic chaotic systems with unknown parameters and uncertain terms. The main work of this paper consists of the following aspects. Firstly, based on the Lyapunov theory in stochastic differential equations and the theory of sliding mode control, we propose a simple sliding surface and discuss the occurrence of the sliding motion. Secondly, we design an adaptive sliding mode controller to realize the asymptotical synchronization in mean squares. Thirdly, we design an adaptive sliding mode controller to realize the almost surely synchronization. Finally, the designed adaptive sliding mode controllers are used to achieve synchronization between two pairs of different stochastic chaos systems (Lorenz-Chen and Chen-Lu in the presence of the uncertainties and unknown parameters. Numerical simulations are given to demonstrate the robustness and efficiency of the proposed robust adaptive sliding mode controller.
A Simple Excitation Control for an Isolated Synchronous Generator ...
African Journals Online (AJOL)
This paper shows a very simple method of determining the range of field voltages to be applied to an isolated synchronous generator from no-load to full load while maintaining the rated terminal voltage on the stator terminals. The d-q rotor reference frame equations were used for the calculations and it is shown that values ...
Synchronization controller design of HIRFL-CSR based on ACEX1K50
International Nuclear Information System (INIS)
Li Guihua; Qiao Weimin; Jing Lan
2011-01-01
The synchronization controller is the core component of Lanzhou HIRFL-CSR synchronous system. As the highest instruction unit and timing unit of HIRFL-CSR control system, it directs the entire system to do the proper thing at the proper time and requires the timing accuracy of nanosecond and very high stability of running. The methods of realizing the main function modules of synchronization processor and the key technologies by using hardware description language (VHDL) on ACEX1K50 chip were introduced. The test results and the actual applications were given. (authors)
International Nuclear Information System (INIS)
Feng Cun-Fang; Wang Ying-Hai
2011-01-01
Projective synchronization in modulated time-delayed systems is studied by applying an active control method. Based on the Lyapunov asymptotical stability theorem, the controller and sufficient condition for projective synchronization are calculated analytically. We give a general method with which we can achieve projective synchronization in modulated time-delayed chaotic systems. This method allows us to adjust the desired scaling factor arbitrarily. The effectiveness of our method is confirmed by using the famous delay-differential equations related to optical bistable or hybrid optical bistable devices. Numerical simulations fully support the analytical approach. (general)
2012-05-07
... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-661] Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and Products Containing Same; Determination Rescinding the Exclusion Order and Cease and Desist Orders AGENCY: U.S. International Trade Commission. ACTION...
CSIR Research Space (South Africa)
Mkuzangwe, NNP
2015-08-01
Full Text Available This work implements two anomaly detection algorithms for detecting Transmission Control Protocol Synchronized (TCP SYN) flooding attack. The two algorithms are an adaptive threshold algorithm and a cumulative sum (CUSUM) based algorithm...
Han, Songshan; Jiao, Zongxia; Yao, Jianyong; Shang, Yaoxing
2014-01-01
An electro-hydraulic load simulator (EHLS) is a typical case of torque systems with strong external disturbances from hydraulic motion systems. A new velocity synchronizing compensation strategy is proposed in this paper to eliminate motion disturbances, based on theoretical and experimental analysis of a structure invariance method and traditional velocity synchronizing compensation controller (TVSM). This strategy only uses the servo-valve's control signal of motion system and torque feedba...
Multivariable PD controller design for fast chaos synchronization of Lur'e systems
International Nuclear Information System (INIS)
Wen, Guilin; Wang, Qing-Guo; He, Yong; Ye, Zhen
2007-01-01
In this Letter, a strategy for fast master-slave synchronization is proposed for Lur'e systems under PD control based on the free-weighting matrix approach and the S-procedure. The purpose of the derivative action is to improve the closed-loop stability and speed synchronization response. The proposed strategy covers the existing result for the proportional control alone as a special case. This approach is illustrated by the Chua's chaotic circuit system
Li, Xiaodi; Song, Shiji
2014-10-01
In this paper, an impulsive controller is designed to achieve the exponential synchronization of chaotic delayed neural networks with stochastic perturbation. By using the impulsive delay differential inequality technique that was established in recent publications, several sufficient conditions ensuring the exponential synchronization of chaotic delayed networks are derived, which can be easily checked by LMI Control Toolbox in Matlab. A numerical example and its simulation is given to demonstrate the effectiveness and advantage of the theory results.
Hopkins, David James [Livermore, CA
2008-05-13
A control system and method for actively reducing vibration in a spindle housing caused by unbalance forces on a rotating spindle, by measuring the force-induced spindle-housing motion, determining control signals based on synchronous demodulation, and provide compensation for the measured displacement to cancel or otherwise reduce or attenuate the vibration. In particular, the synchronous demodulation technique is performed to recover a measured spindle housing displacement signal related only to the rotation of a machine tool spindle, and consequently rejects measured displacement not related to spindle motion or synchronous to a cycle of revolution. Furthermore, the controller actuates at least one voice-coil (VC) motor, to cancel the original force-induced motion, and adapts the magnitude of voice coil signal until this measured displacement signal is brought to a null. In order to adjust the signal to a null, it must have the correct phase relative to the spindle angle. The feedback phase signal is used to adjust a common (to both outputs) commutation offset register (offset relative to spindle encoder angle) to force the feedback phase signal output to a null. Once both of these feedback signals are null, the system is compensating properly for the spindle-induced motion.
DEFF Research Database (Denmark)
Lascu, Christian; Boldea, Ion; Blaabjerg, Frede
2013-01-01
This paper investigates a permanent magnet synchronous motor drive controlled by a second-order variable structure control technique, known as the super-twisting sliding modes (STSM) control. The STSM controller is designed as a direct torque and flux controller and it works in the stator flux...
Lu, Tongli; Li, Hongkui; Zhang, Jianwu; Hao, Hongtao
2016-01-01
The objective of this paper is to improve the performance of the synchronizer control strategy by considering the effect of clutch drag torque. The research of synchronization process in wet dual clutch transmission is performed in this paper. The significant effect of clutch drag torque is analyzed by adding a complex clutch drag torque module to synchronizer model. This paper focuses on the development of original estimation method of clutch drag torque. The estimation method offers an effective way to obtain accurate clutch drag torque, and it is applied to develop a new supervisor control strategy. Results have demonstrated that the estimation method has satisfied efficiency and accuracy and the control strategy improves the performance of the synchronizer mechanism significantly.
International Nuclear Information System (INIS)
Jin, Maolin; Chang, Pyung Hun
2009-01-01
This work presents two simple and robust techniques based on time delay estimation for the respective control and synchronization of chaos systems. First, one of these techniques is applied to the control of a chaotic Lorenz system with both matched and mismatched uncertainties. The nonlinearities in the Lorenz system is cancelled by time delay estimation and desired error dynamics is inserted. Second, the other technique is applied to the synchronization of the Lue system and the Lorenz system with uncertainties. The synchronization input consists of three elements that have transparent and clear meanings. Since time delay estimation enables a very effective and efficient cancellation of disturbances and nonlinearities, the techniques turn out to be simple and robust. Numerical simulation results show fast, accurate and robust performance of the proposed techniques, thereby demonstrating their effectiveness for the control and synchronization of Lorenz systems.
Speed Synchronization of Multi Induction Motors with Fuzzy Sliding Mode Control
Directory of Open Access Journals (Sweden)
HACHEMI Glaoui
2013-05-01
Full Text Available A continuous web winding system is a large-scale, complex interconnected dynamic system with numerous tension zones to transport the web while processing it. There are two control schemes for large-scale system control: the centralized scheme and the decentralized scheme. Centralized control is the traditional control method, which considers all the information about the system to be a single dynamic model and design a control system for this model. Aspeed synchronization control strategy for multiple induction motors, based on adjacent cross-coupling control structure, is developed by employing total sliding mode control method. The proposed controlstrategy is to stabilize speed tracking of each induction motor while synchronizing its speed with the speed of the other motors so as to make speed synchronization error amongst induction motors converge to zero. The global stability and the convergence of the designedcontroller are proved by using Lyapunov method. Simulation results demonstrate the effectiveness of the proposed method.
Directory of Open Access Journals (Sweden)
Tor A. Johansen
2004-01-01
Full Text Available A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerged vessel with a moonpool shows that wave synchronization leads to significant improvements in performance. Depending on the sea state and payload, the results indicate that the reduction in the standard deviation of the wire tension may be up to 50
Stabilization and synchronization of Genesio-Tesi system via single variable feedback controller
International Nuclear Information System (INIS)
Wang Guangming
2010-01-01
This Letter investigates the stabilization and synchronization of Genesio-Tesi systems. Firstly, modifying the previous method, we stabilize the Genesio-Tesi system. Then, we synchronize two identical Genesio chaotic system by extending the obtained stabilization results. To the best of our knowledge, the above controllers obtained in this Letter are simpler than those obtained in the existing results. Finally, numerical simulations verify the effectiveness and the validity of the above theoretical results.
f-MAC: A Deterministic Media Access Control Protocol Without Time Synchronization
Roedig, Utz; Barroso, Andre; Sreenan, Cormac J.
2006-01-01
Nodes in a wireless network transmit messages through a shared medium. Thus, a Media Access Control (MAC) protocol is necessary to regulate and coordinate medium access. For some application areas it is necessary to have a deterministic MAC protocol which can give guarantees on message delay and channel throughput. Schedule based MAC protocols, based on time synchronization among nodes, are currently used to implement deterministic MAC protocols. Time synchronization is difficult and costly, ...
Directory of Open Access Journals (Sweden)
Baghdad BELABES
2008-12-01
Full Text Available In this paper a hybrid controller combining a linear model following controller (LMFC and fuzzy logic control (FLC for speed vector controlled permanent magnet synchronous motor (PMSM is described on this study. The FLC is introduced at the adaptive mechanism level. First, an LMFC system is designed to allow the plant states to be controlled to follow the states produced by a reference model. In the nominal conditions, the model following is perfect and the adaptive mechanism based on the fuzzy logic is idle. Secondly, when parameter variations or external disturbances occur, an augmented signal will be generated by FLC mechanism to preserve the desired model following control performance. The effectiveness and robustness of the proposed controller is demonstrated by some simulation results.
Speed Control Design of Permanent Magnet Synchronous Motor using TakagiSugeno Fuzzy Logic Control
Directory of Open Access Journals (Sweden)
Ahmad Asri Abd Samat
2017-12-01
Full Text Available This paper proposes a speed control design of Permanent Magnet Synchronous Motor (PMSM using Field Oriented Control (FOC. The focus is to design a speed control using Takagi — Sugeno Fuzzy Logic Control (T-S FLS. These systems will replace the conventional method which is proportional-integral (PI. The objective of this paper is to study the T—S Fuzzy Inference System (FIS speed regulator and acceleration observer for PMSM. The scope of study basically is to design and analyse the Takagi Sugeno FLC and the PMSM. This paper also will describe the methodology and process of modelling the PMSM including data analysis. The simulation work is implemented in Matlab-Simulink to verify the control method. The effectiveness of this proposed control method was confirmed through various range of speed and torque variation.
Robust synchronization control of coupled chaotic neurons under external electrical stimulation
International Nuclear Information System (INIS)
Che Yanqiu; Wang Jiang; Zhou Sisi; Deng Bin
2009-01-01
In this paper, a robust adaptive neural network (NN) controller is proposed to realize the synchronization of two gap junction coupled chaotic FitzHugh-Nagumo (FHN) neurons under external electrical stimulation. Based on the Lyapunov stability theory, we derive the update laws of NN for approximating the nonlinear uncertain functions of the error dynamical system. The control scheme is robust to the uncertainties such as approximate error, ionic channel noise and external disturbances. Chaos synchronization is obtained by proper choice of the control parameters. The simulation results demonstrate the effectiveness of the proposed control method.
An FPGA-Based PID Controller Design for Chaos Synchronization by Evolutionary Programming
Directory of Open Access Journals (Sweden)
Her-Terng Yau
2011-01-01
Full Text Available This paper is concerned with the design of a field programmable gate arrays- (FPGAs- based digital proportional-integral-derivative (PID controller for synchronization of a continuous chaotic model. By using the evolutionary programming (EP algorithm, optimal control gains in PID-controlled chaotic systems are derived such that a performance index of integrated absolute error (IAE is as minimal as possible. To verify the system performance, basic electronic components, including OPA resistor and capacitor elements, were used to implement the chaotic Sprott circuits, and FPGA technology was used to implement the proposed digital PID controller. Numerical and experimental results confirmed the effectiveness of the proposed synchronization procedure.
Design of permanent magnet synchronous motor speed control system based on SVPWM
Wu, Haibo
2017-04-01
The control system is designed to realize TMS320F28335 based on the permanent magnet synchronous motor speed control system, and put it to quoting all electric of injection molding machine. The system of the control method used SVPWM, through the sampling motor current and rotating transformer position information, realize speed, current double closed loop control. Through the TMS320F28335 hardware floating-point processing core, realize the application for permanent magnet synchronous motor in the floating point arithmetic, to replace the past fixed-point algorithm, and improve the efficiency of the code.
Synchronization control of Hodgkin-Huxley neurons exposed to ELF electric field
International Nuclear Information System (INIS)
Che Yanqiu; Wang Jiang; Zhou Sisi; Deng Bin
2009-01-01
This paper presents an adaptive neural network H ∞ control for unidirectional synchronization of modified Hodgkin-Huxley (HH) neurons exposed to extremely low frequency (ELF) electric field. The proposed modified HH neurons exhibit periodic and chaotic dynamics in response to sinusoidal electric field stimulation. Based on the Lyapunov stability theory, we derive the updated laws of neural network for approximating the nonlinear uncertain functions of the error dynamical system. The H ∞ design technique makes the controller robust to unmodeled dynamics, disturbances and approximate errors. The proposed controller not only ensures closed-loop stability, but also guarantees an H ∞ performance for the synchronization error system. The states of the controlled slave system exponentially synchronize with that of the master one after control. The simulation results demonstrate the validity of the proposed method.
Energy Technology Data Exchange (ETDEWEB)
Feng Xiuqin [Department of Physics, ChangChun University of Science and Technology, ChangChun 130022 (China)], E-mail: Fengxq@cust.edu.cn; Shen Ke [Department of Physics, ChangChun University of Science and Technology, ChangChun 130022 (China)
2008-02-15
Hyperchaotic behaviors can be controlled and converted into periodic behaviors by modulating the detuned parameters using an external periodic signal in degenerated optical parameter oscillator (DOPO). Numerical simulations show that the period number differs on the account of the modulating coefficient. Increasing the modulating coefficient, the DOPO results in conversion to periodic orbits. Subsequently it is converted into period 2, and then into period 1. It was also shown that the periodic orbits of the DOPOs modulated through external periodic signal can result in identical synchronization or anti-synchronization only in the case that the largest Lyapunov exponent of the system is negative. Thus synchronization types and evolution process of synchronization is determined by modulating coefficient and initial conditions.
Adaptive Synchronization of Fractional Order Complex-Variable Dynamical Networks via Pinning Control
Ding, Da-Wei; Yan, Jie; Wang, Nian; Liang, Dong
2017-09-01
In this paper, the synchronization of fractional order complex-variable dynamical networks is studied using an adaptive pinning control strategy based on close center degree. Some effective criteria for global synchronization of fractional order complex-variable dynamical networks are derived based on the Lyapunov stability theory. From the theoretical analysis, one concludes that under appropriate conditions, the complex-variable dynamical networks can realize the global synchronization by using the proper adaptive pinning control method. Meanwhile, we succeed in solving the problem about how much coupling strength should be applied to ensure the synchronization of the fractional order complex networks. Therefore, compared with the existing results, the synchronization method in this paper is more general and convenient. This result extends the synchronization condition of the real-variable dynamical networks to the complex-valued field, which makes our research more practical. Finally, two simulation examples show that the derived theoretical results are valid and the proposed adaptive pinning method is effective. Supported by National Natural Science Foundation of China under Grant No. 61201227, National Natural Science Foundation of China Guangdong Joint Fund under Grant No. U1201255, the Natural Science Foundation of Anhui Province under Grant No. 1208085MF93, 211 Innovation Team of Anhui University under Grant Nos. KJTD007A and KJTD001B, and also supported by Chinese Scholarship Council
Synchronization of chaotic systems with parameter uncertainties via variable structure control
International Nuclear Information System (INIS)
Etemadi, Shahram; Alasty, Aria; Salarieh, Hassan
2006-01-01
The Letter introduces a robust control design method to synchronize a pair of different uncertain chaotic systems. The technique is based on sliding-mode and variable structure control theories. Comparison of proposed method with previous works is performed during simulations. It is shown that the proposed controller while appearing in a faster response, is able to overcome random uncertainties of all model parameters
Nonlinear Control and Synchronization with Time Delays of Multiagent Robotic Systems
Directory of Open Access Journals (Sweden)
Yassine Bouteraa
2011-01-01
Full Text Available We investigate the cooperative control and global asymptotic synchronization Lagrangian system groups, such as industrial robots. The proposed control approach works to accomplish multirobot systems synchronization under an undirected connected communication topology. The control strategy is to synchronize each robot in position and velocity to others robots in the network with respect to the common desired trajectory. The cooperative robot network only requires local neighbor-to-neighbor information exchange between manipulators and does not assume the existence of an explicit leader in the team. It is assumed that network robots have the same number of joints and equivalent joint work spaces. A combination of the lyapunov-based technique and the cross-coupling method has been used to establish the multirobot system asymptotic stability. The developed control combines trajectory tracking and coordination algorithms. To address the time-delay problem in the cooperative network communication, the suggested synchronization control law is shown to synchronize multiple robots as well as to track given trajectory, taking into account the presence of the time delay. To this end, Krasovskii functional method has been used to deal with the delay-dependent stability problem.
International Nuclear Information System (INIS)
Karakaya, A.; Karakas, E.
2008-01-01
Permanent Magnet Synchronous Motors have nonlinear characteristics whose dynamics changes with time. In spite of this structure the permanent magnet synchronous motor has answered engineering problems in industry such as motion control which need high torque values. This paper obtains a nonlinear mathematical model for Permanent Magnet Synchronous Motor and realizes stimulation of the obtained model in the Matlab/Simulink program. Motor parameters are determined by an experimental set-up and they are used in the motor model. Speed control of motor model is made with Fuzzy Logic and Self Tuning logic PI controllers. Using the speed graphs obtained, rise time, overshoot, steady-state error and settling time are analyzed and controller performances are compared. (author)
Pinning synchronization of two general complex networks with periodically intermittent control
Directory of Open Access Journals (Sweden)
Meng Fanyu
2015-12-01
Full Text Available In this paper, the method of periodically pinning intermittent control is introduced to solve the problem of outer synchronization between two complex networks. Based on the Lyapunov stability theory, differential inequality method and adaptive technique, some simple synchronous criteria have been derived analytically. At last, both the theoretical and numerical analysis illustrate the effectiveness of the proposed control methodology. This method not only reduces the conservatism of control gain but also saves the cost of production.These advantages make this method having a large application scope in the real production process.
Gao, Changwei; Liu, Xiaoming; Chen, Hai
2017-08-22
This paper focus on the power fluctuations of the virtual synchronous generator(VSG) during the transition process. An improved virtual synchronous generator(IVSG) control strategy based on feed-forward compensation is proposed. Adjustable parameter of the compensation section can be modified to achieve the goal of reducing the order of the system. It can effectively suppress the power fluctuations of the VSG in transient process. To verify the effectiveness of the proposed control strategy for distributed energy resources inverter, the simulation model is set up in MATLAB/SIMULINK platform and physical experiment platform is established. Simulation and experiment results demonstrate the effectiveness of the proposed IVSG control strategy.
Wang, Minlin; Ren, Xuemei; Chen, Qiang
2018-01-01
The multi-motor servomechanism (MMS) is a multi-variable, high coupling and nonlinear system, which makes the controller design challenging. In this paper, an adaptive robust H-infinity control scheme is proposed to achieve both the load tracking and multi-motor synchronization of MMS. This control scheme consists of two parts: a robust tracking controller and a distributed synchronization controller. The robust tracking controller is constructed by incorporating a neural network (NN) K-filter observer into the dynamic surface control, while the distributed synchronization controller is designed by combining the mean deviation coupling control strategy with the distributed technique. The proposed control scheme has several merits: 1) by using the mean deviation coupling synchronization control strategy, the tracking controller and the synchronization controller can be designed individually without any coupling problem; 2) the immeasurable states and unknown nonlinearities are handled by a NN K-filter observer, where the number of NN weights is largely reduced by using the minimal learning parameter technique; 3) the H-infinity performances of tracking error and synchronization error are guaranteed by introducing a robust term into the tracking controller and the synchronization controller, respectively. The stabilities of the tracking and synchronization control systems are analyzed by the Lyapunov theory. Simulation and experimental results based on a four-motor servomechanism are conducted to demonstrate the effectiveness of the proposed method. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Pyrhoenen, O.
1998-12-31
Direct torque control (DTC) is a new control method for rotating field electrical machines. DTC controls directly the motor stator flux linkage with the stator voltage, and no stator current controllers are used. With the DTC method very good torque dynamics can be achieved. Until now, DTC has been applied to asynchronous motor drives. The purpose of this work is to analyse the applicability of DTC to electrically excited synchronous motor drives. Compared with asynchronous motor drives, electrically excited synchronous motor drives require an additional control for the rotor field current. The field current control is called excitation control in this study. The dependence of the static and dynamic performance of DTC synchronous motor drives on the excitation control has been analysed and a straightforward excitation control method has been developed and tested. In the field weakening range the stator flux linkage modulus must be reduced in order to keep the electro motive force of the synchronous motor smaller than the stator voltage and in order to maintain a sufficient voltage reserve. The dynamic performance of the DTC synchronous motor drive depends on the stator flux linkage modulus. Another important factor for the dynamic performance in the field weakening range is the excitation control. The field weakening analysis considers both dependencies. A modified excitation control method, which maximises the dynamic performance in the field weakening range, has been developed. In synchronous motor drives the load angle must be kept in a stabile working area in order to avoid loss of synchronism. The traditional vector control methods allow to adjust the load angle of the synchronous motor directly by the stator current control. In the DTC synchronous motor drive the load angle is not a directly controllable variable, but it is formed freely according to the motor`s electromagnetic state and load. The load angle can be limited indirectly by limiting the torque
Megam Ngouonkadi, Elie Bertrand; Fotsin, Hilaire Bertrand; Kabong Nono, Martial; Louodop Fotso, Patrick Herve
2016-10-01
In this paper, we report on the synchronization of a pacemaker neuronal ensemble constituted of an AB neuron electrically coupled to two PD neurons. By the virtue of this electrical coupling, they can fire synchronous bursts of action potential. An external master neuron is used to induce to the whole system the desired dynamics, via a nonlinear controller. Such controller is obtained by a combination of sliding mode and feedback control. The proposed controller is able to offset uncertainties in the synchronized systems. We show how noise affects the synchronization of the pacemaker neuronal ensemble, and briefly discuss its potential benefits in our synchronization scheme. An extended Hindmarsh-Rose neuronal model is used to represent a single cell dynamic of the network. Numerical simulations and Pspice implementation of the synchronization scheme are presented. We found that, the proposed controller reduces the stochastic resonance of the network when its gain increases.
International Nuclear Information System (INIS)
Yan Zhenya; Yu Pei
2007-01-01
In this paper, we study chaos (lag) synchronization of a new LC chaotic system, which can exhibit not only a two-scroll attractor but also two double-scroll attractors for different parameter values, via three types of state feedback controls: (i) linear feedback control; (ii) adaptive feedback control; and (iii) a combination of linear feedback and adaptive feedback controls. As a consequence, ten families of new feedback control laws are designed to obtain global chaos lag synchronization for τ < 0 and global chaos synchronization for τ = 0 of the LC system. Numerical simulations are used to illustrate these theoretical results. Each family of these obtained feedback control laws, including two linear (adaptive) functions or one linear function and one adaptive function, is added to two equations of the LC system. This is simpler than the known synchronization controllers, which apply controllers to all equations of the LC system. Moreover, based on the obtained results of the LC system, we also derive the control laws for chaos (lag) synchronization of another new type of chaotic system
Direct torque control via feedback linearization for permanent magnet synchronous motor drives
DEFF Research Database (Denmark)
Lascu, Cristian; Boldea, Ion; Blaabjerg, Frede
2012-01-01
The paper describes a direct torque controlled (DTC) permanent magnet synchronous motor (PMSM) drive that employs feedback linearization and uses sliding-mode and linear controllers. We introduce a new feedback linearization approach that yields a decoupled linear PMSM model with two state...
Adaptive Synchronization of Grid-Connected Threephase Inverters by Using Virtual Oscillator Control
DEFF Research Database (Denmark)
Li, Mingshen; Gui, Yonghao; Guerrero, Josep M.
2018-01-01
This paper presents an adaptive synchronization for current-controlled grid-connected inverter based on a time domain virtual oscillator controller (VOC). Inspired by the phenomenon of dynamics of adaptive oscillator under the perturbation effect. Firstly, the fast learning rule of the oscillator...
Directory of Open Access Journals (Sweden)
Toshiaki Iwata
2011-01-01
Full Text Available The remote synchronization system for the onboard crystal oscillator (RESSOX is a remote control method that permits synchronization between a ground station atomic clock and Japanese quasi-zenith satellite system (QZSS crystal oscillators. To realize the RESSOX of the QZSS, the utilization of navigation signals of QZSS for feedback control is an important issue. Since QZSS transmits seven navigation signals (L1C/A, L1CP, L1CD, L2CM, L2CL, L5Q, and L5I, all combinations of these signals should be evaluated. First, the RESSOX algorithm will be introduced. Next, experimental performance will be demonstrated. If only a single signal is available, ionospheric delay should be input from external measurements. If multiple frequency signals are available, any combination, except for L2 and L5, gives good performance with synchronization error being within two nanoseconds that of RESSOX. The combination of L1CD and L5Q gives the best synchronization performance (synchronization error within 1.14 ns. Finally, in the discussion, comparisons of long-duration performance, computer simulation, and sampling number used in feedback control are considered. Although experimental results do not correspond to the simulation results, the tendencies are similar. For the overlapping Allan deviation of long duration, the stability of 1.23×10−14 at 100,160 s is obtained.
Su, Housheng
2013-01-01
Synchronization, consensus and flocking are ubiquitous requirements in networked systems. Pinning Control of Complex Networked Systems investigates these requirements by using the pinning control strategy, which aims to control the whole dynamical network with huge numbers of nodes by imposing controllers for only a fraction of the nodes. As the direct control of every node in a dynamical network with huge numbers of nodes might be impossible or unnecessary, it’s then very important to use the pinning control strategy for the synchronization of complex dynamical networks. The research on pinning control strategy in consensus and flocking of multi-agent systems can not only help us to better understand the mechanisms of natural collective phenomena, but also benefit applications in mobile sensor/robot networks. This book offers a valuable resource for researchers and engineers working in the fields of control theory and control engineering. Housheng Su is an Associate Professor at the Department of Contro...
Gong, Shuqing; Yang, Shaofu; Guo, Zhenyuan; Huang, Tingwen
2018-06-01
The paper is concerned with the synchronization problem of inertial memristive neural networks with time-varying delay. First, by choosing a proper variable substitution, inertial memristive neural networks described by second-order differential equations can be transformed into first-order differential equations. Then, a novel controller with a linear diffusive term and discontinuous sign term is designed. By using the controller, the sufficient conditions for assuring the global exponential synchronization of the derive and response neural networks are derived based on Lyapunov stability theory and some inequality techniques. Finally, several numerical simulations are provided to substantiate the effectiveness of the theoretical results. Copyright © 2018 Elsevier Ltd. All rights reserved.
Wang, Tianbo; Zhou, Wuneng; Zhao, Shouwei; Yu, Weiqin
2014-03-01
In this paper, the robust exponential synchronization problem for a class of uncertain delayed master-slave dynamical system is investigated by using the adaptive control method. Different from some existing master-slave models, the considered master-slave system includes bounded unmodeled dynamics. In order to compensate the effect of unmodeled dynamics and effectively achieve synchronization, a novel adaptive controller with simple updated laws is proposed. Moreover, the results are given in terms of LMIs, which can be easily solved by LMI Toolbox in Matlab. A numerical example is given to illustrate the effectiveness of the method. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Miao Shi
2013-01-01
Full Text Available Adaptive synchronization control is proposed for a new complex dynamical network model with nonidentical nodes and nonderivative and derivative couplings. The distributed adaptive learning laws of periodically time-varying and constant parameters and distributed adaptive control are designed. The new method which can obtain the synchronization error of closed-loop complex network system is asymptotic convergence in the sense of square error norm. What is more, the coupling matrix is not assumed to be symmetric or irreducible. Finally, a simulation example shows the feasibility and effectiveness of the approach.
Synchronization of variable-order fractional financial system via active control method
Xu, Yufeng; He, Zhimin
2013-06-01
In this paper, we study the chaotic dynamics of a Variable-Order Fractional Financial System (VOFFS). The Variable-Order Fractional Derivative (VOFD) is defined in Caputo type. A necessary condition for occurrence of chaos in VOFFS is obtained. Numerical experiments on the dynamics of the VOFFS with various conditions are given. Based on them, it is shown that the VOFFS has complex dynamical behavior, and the occurrence of chaos depends on the choice of order function. Furthermore, the chaos synchronization of the VOFFS is studied via active control method. Numerical simulations demonstrate that the active control method is effective and simple for synchronizing the VOFFSs with commensurate or incommensurate order functions.
FNAL Booster intensity, extraction, and synchronization control for collider operation
International Nuclear Information System (INIS)
Ducar, R.J.; Lackey, J.R.; Tawzer, S.R.
1987-03-01
Booster operation for collider physics is considerably different than for fixed target operation. Various scenarios for collider physics, machine studies, and P-Bar targeting may require that the intensity vary from 5E10 PPP to 3E12 PPP at a 15 Hertz machine cycle rate. In addition to the normal Booster single turn extraction mode, collider operations require that the Booster inject into the Main Ring a small number of beam bunches for coalescing into a single high intensity bunch. These bunches must be synchronized such that the center bunch arrives in the RF bucket which corresponds to the zero phase of the coalescing cavity. The system implemented has the ability to deliver a precise fraction of the available 84 Booster beam bunches to Main Ring or to the P-Bar Debuncher via the newly installed AP-4 beam line for tune-up and studies. It is required that all of the various intensity and extraction scenarios be accommodated with minimal operator intervention
Fnal booster intensity, extraction, and synchronization control for collider operation
International Nuclear Information System (INIS)
Ducar, R.J.; Lackey, J.R.; Tawzer, S.R.
1987-01-01
Booster operation for collider physics is considerably different than for fixed target operation. Various scenarios for collider physics, machine studies, and P-Bar targeting may require that the intensity vary from 5E10 PPP to 3E12 PPP at a 15 Hertz machine cycle rate. In addition to the normal Booster single turn extraction mode, collider operations require that the Booster inject into the Main Ring a small number of beam bunches for coalescing into a single high intensity bunch. These bunches must be synchronized such that the center bunch arrives in the RF bucket which corresponds to the zero phase of the coalescing cavity. The system implemented has the ability to deliver a precise fraction of the availability 84 Booster beam bunches to Main Ring or to the P-Bar Debuncher via the newly installed AP-4 beam line for tune-up and studies. It is required that all of the various intensity and extraction scenarios be accommodated with minimal operator intervention
Directory of Open Access Journals (Sweden)
Junwei Sun
2014-01-01
Full Text Available Some important dynamical properties of the memristor chaotic oscillator system have been studied in the paper. A novel hybrid dislocated control method and a general hybrid projective dislocated synchronization scheme have been realized for memristor chaotic oscillator system. The paper firstly presents hybrid dislocated control method for stabilizing chaos to the unstable equilibrium point. Based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization has been studied for the drive memristor chaotic oscillator system and the same response memristor chaotic oscillator system. For the different dimensions, the memristor chaotic oscillator system and the other chaotic system have realized general hybrid projective dislocated synchronization. Numerical simulations are given to show the effectiveness of these methods.
PID control design for chaotic synchronization using a tribes optimization approach
Energy Technology Data Exchange (ETDEWEB)
Santos Coelho, Leandro dos [Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Pontifical Catholic University of Parana, PUCPR, Imaculada Conceicao, 1155, 80215-901 Curitiba, Parana (Brazil)], E-mail: leandro.coelho@pucpr.br; Andrade Bernert, Diego Luis de [Industrial and Systems Engineering Graduate Program, LAS/PPGEPS, Pontifical Catholic University of Parana, PUCPR, Imaculada Conceicao, 1155, 80215-901 Curitiba, Parana (Brazil)], E-mail: dbernert@gmail.com
2009-10-15
Recently, the investigation of synchronization and control problems for discrete chaotic systems has stimulated a wide range of research activity including both theoretical studies and practical applications. This paper deals with the tuning of a proportional-integral-derivative (PID) controller using a modified Tribes optimization algorithm based on truncated chaotic Zaslavskii map (MTribes) for synchronization of two identical discrete chaotic systems subject the different initial conditions. The Tribes algorithm is inspired by the social behavior of bird flocking and is also an optimization adaptive procedure that does not require sociometric or swarm size parameter tuning. Numerical simulations are given to show the effectiveness of the proposed synchronization method. In addition, some comparisons of the MTribes optimization algorithm with other continuous optimization methods, including classical Tribes algorithm and particle swarm optimization approaches, are presented.
PID control design for chaotic synchronization using a tribes optimization approach
International Nuclear Information System (INIS)
Santos Coelho, Leandro dos; Andrade Bernert, Diego Luis de
2009-01-01
Recently, the investigation of synchronization and control problems for discrete chaotic systems has stimulated a wide range of research activity including both theoretical studies and practical applications. This paper deals with the tuning of a proportional-integral-derivative (PID) controller using a modified Tribes optimization algorithm based on truncated chaotic Zaslavskii map (MTribes) for synchronization of two identical discrete chaotic systems subject the different initial conditions. The Tribes algorithm is inspired by the social behavior of bird flocking and is also an optimization adaptive procedure that does not require sociometric or swarm size parameter tuning. Numerical simulations are given to show the effectiveness of the proposed synchronization method. In addition, some comparisons of the MTribes optimization algorithm with other continuous optimization methods, including classical Tribes algorithm and particle swarm optimization approaches, are presented.
Directory of Open Access Journals (Sweden)
Hendrik B Tiedemann
2014-10-01
Full Text Available While it is known that a large fraction of vertebrate genes are under the control of a gene regulatory network (GRN forming a clock with circadian periodicity, shorter period oscillatory genes like the Hairy-enhancer-of split (Hes genes are discussed mostly in connection with the embryonic process of somitogenesis. They form the core of the somitogenesis-clock, which orchestrates the periodic separation of somites from the presomitic mesoderm (PSM. The formation of sharp boundaries between the blocks of many cells works only when the oscillators in the cells forming the boundary are synchronized. It has been shown experimentally that Delta-Notch (D/N signaling is responsible for this synchronization. This process has to happen rather fast as a cell experiences at most five oscillations from its 'birth' to its incorporation into a somite. Computer simulations describing synchronized oscillators with classical modes of D/N-interaction have difficulties to achieve synchronization in an appropriate time. One approach to solving this problem of modeling fast synchronization in the PSM was the consideration of cell movements. Here we show that fast synchronization of Hes-type oscillators can be achieved without cell movements by including D/N cis-inhibition, wherein the mutual interaction of DELTA and NOTCH in the same cell leads to a titration of ligand against receptor so that only one sort of molecule prevails. Consequently, the symmetry between sender and receiver is partially broken and one cell becomes preferentially sender or receiver at a given moment, which leads to faster entrainment of oscillators. Although not yet confirmed by experiment, the proposed mechanism of enhanced synchronization of mesenchymal cells in the PSM would be a new distinct developmental mechanism employing D/N cis-inhibition. Consequently, the way in which Delta-Notch signaling was modeled so far should be carefully reconsidered.
Tiedemann, Hendrik B; Schneltzer, Elida; Zeiser, Stefan; Wurst, Wolfgang; Beckers, Johannes; Przemeck, Gerhard K H; Hrabě de Angelis, Martin
2014-10-01
While it is known that a large fraction of vertebrate genes are under the control of a gene regulatory network (GRN) forming a clock with circadian periodicity, shorter period oscillatory genes like the Hairy-enhancer-of split (Hes) genes are discussed mostly in connection with the embryonic process of somitogenesis. They form the core of the somitogenesis-clock, which orchestrates the periodic separation of somites from the presomitic mesoderm (PSM). The formation of sharp boundaries between the blocks of many cells works only when the oscillators in the cells forming the boundary are synchronized. It has been shown experimentally that Delta-Notch (D/N) signaling is responsible for this synchronization. This process has to happen rather fast as a cell experiences at most five oscillations from its 'birth' to its incorporation into a somite. Computer simulations describing synchronized oscillators with classical modes of D/N-interaction have difficulties to achieve synchronization in an appropriate time. One approach to solving this problem of modeling fast synchronization in the PSM was the consideration of cell movements. Here we show that fast synchronization of Hes-type oscillators can be achieved without cell movements by including D/N cis-inhibition, wherein the mutual interaction of DELTA and NOTCH in the same cell leads to a titration of ligand against receptor so that only one sort of molecule prevails. Consequently, the symmetry between sender and receiver is partially broken and one cell becomes preferentially sender or receiver at a given moment, which leads to faster entrainment of oscillators. Although not yet confirmed by experiment, the proposed mechanism of enhanced synchronization of mesenchymal cells in the PSM would be a new distinct developmental mechanism employing D/N cis-inhibition. Consequently, the way in which Delta-Notch signaling was modeled so far should be carefully reconsidered.
Li, Kunpeng
2017-01-01
The compatibility problem between rapidity and overshooting in the traditional predictive current control structure is inevitable and difficult to solve by reason of using PI controller. A novel predictive current control (PCC) algorithm for permanent magnet synchronous motor (PMSM) based on linear active disturbance rejection control (LADRC) is presented in this paper. In order to displace PI controller, the LADRC strategy which consisted of linear state error feedback (LSEF) control algorithm and linear extended state observer (LESO), is designed based on the mathematic model of PMSM. The purpose of LSEF is to make sure fast response to load mutation and system uncertainties, and LESO is designed to estimate the uncertain disturbances. The principal structures of the proposed system are speed outer loop based on LADRC and current inner loop based on predictive current control. Especially, the instruction value of qaxis current in inner loop is derived from the control quantity which is designed in speed outer loop. The simulation is carried out in Matlab/Simulink software, and the results illustrate that the dynamic and static performances of proposed system are satisfied. Moreover the robust against model parameters mismatch is enhanced obviously.
Directory of Open Access Journals (Sweden)
Ting Yan
2017-01-01
Full Text Available Considering the inherent disadvantages that severely affect driving comfortability during the shift process in HEVs, a dynamic shift coordinated control based on motor active speed synchronization is proposed to improve shift quality by reduction of shift vibration. The whole control scheme is comprised of three phases, preparatory phase, speed regulation phase, and synchronization phase, which are implemented consecutively in order. The key to inhibiting impact and jerk depends on the speed regulation phase, where motor active speed synchronization is utilized to reach the minimum speed difference between the two ends of synchronizer. A new hybrid system with superior performances is applied to present the validity of the adopted control algorithm during upshift or downshift, which can represent planetary gear system and conventional AMT shift procedure, respectively. Bench test, simulation, and road test results show that, compared with other methods, the proposed dynamic coordinated control can achieve shifting control in real time to effectively improve gear-shift comfort and shorten power interruption transients, with robustness in both conventional AMT and planetary gear train.
Muhammad, Riaz; Muhammad, Rehan; Keum-Shik, Hong; Muhammad, Ashraf; Haroon, Ur Rasheed
2014-11-01
This paper addresses the control law design for synchronization of two different chaotic oscillators with mutually Lipschitz nonlinearities. For analysis of the properties of two different nonlinearities, an advanced mutually Lipschitz condition is proposed. This mutually Lipschitz condition is more general than the traditional Lipschitz condition. Unlike the latter, it can be used for the design of a feedback controller for synchronization of chaotic oscillators of different dynamics. It is shown that any two different Lipschitz nonlinearities always satisfy the mutually Lipschitz condition. Applying the mutually Lipschitz condition, a quadratic Lyapunov function and uniformly ultimately bounded stability, easily designable and implementable robust control strategies utilizing algebraic Riccati equation and linear matrix inequalities, are derived for synchronization of two distinct chaotic oscillators. Furthermore, a novel adaptive control scheme for mutually Lipschitz chaotic systems is established by addressing the issue of adaptive cancellation of unknown mismatch between the dynamics of different chaotic systems. The proposed control technique is numerically tested for synchronization of two different chaotic Chua's circuits and for obtaining identical behavior between the modified Chua's circuit and the Rössler system.
Robust chaos synchronization using input-to-state stable control
Indian Academy of Sciences (India)
... be obtained by solving a convex optimization problem represented by the. LMI. Simulation studies are presented to demonstrate the effectiveness of the proposed ... one is the linear state feedback controller and the other is the nonlinear feedback controller. By the proposed control scheme, the closed-loop error system is ...
Synchronized Phasor Measurement Units : Implementation of PMU Algorithm on HVDC Control Platform
Deo, Samarth
2013-01-01
Power Systems most often operate in the margins of stability limits. With power grids becoming even more automated now, Phasor Measurement Units (PMU’s) and Phasor Data Concentrators (PDC’s) become essential for real-time control of the system. Since PMU’s are time synchronized, the phasors can be compared at the substations, studied for any faults and analyzed at the same time. These PMU’s report the measured magnitude, phasor angle of voltages and currents in real synchronized time in diffe...
Yang, Shiju; Li, Chuandong; Huang, Tingwen
2016-03-01
The problem of exponential stabilization and synchronization for fuzzy model of memristive neural networks (MNNs) is investigated by using periodically intermittent control in this paper. Based on the knowledge of memristor and recurrent neural network, the model of MNNs is formulated. Some novel and useful stabilization criteria and synchronization conditions are then derived by using the Lyapunov functional and differential inequality techniques. It is worth noting that the methods used in this paper are also applied to fuzzy model for complex networks and general neural networks. Numerical simulations are also provided to verify the effectiveness of theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Zhou Jin; Chen Tianping; Xiang Lan
2006-01-01
This paper investigates synchronization dynamics of delayed neural networks with all the parameters unknown. By combining the adaptive control and linear feedback with the updated law, some simple yet generic criteria for determining the robust synchronization based on the parameters identification of uncertain chaotic delayed neural networks are derived by using the invariance principle of functional differential equations. It is shown that the approaches developed here further extend the ideas and techniques presented in recent literature, and they are also simple to implement in practice. Furthermore, the theoretical results are applied to a typical chaotic delayed Hopfied neural networks, and numerical simulation also demonstrate the effectiveness and feasibility of the proposed technique
DEFF Research Database (Denmark)
Cheng, Shuangyin; Luo, Derong; Huang, Shoudao
2015-01-01
This study presents an investigation into the control of an axial-flux permanent magnet synchronous machine (PMSM) with contra-rotating rotors fed by a single inverter, which corresponds to two PMSM connected in series. In this study, the mathematic model of the PMSM with contra-rotating rotors...
DEFF Research Database (Denmark)
Xie, Ge
The Permanent Magnet Synchronous Machine (PMSM) has become an attractive candidate for various industrial applications due to its high efficiency and torque density. In the PMSM drive system, simple and robust control methods play an important role in achieving satisfactory drive performances...
Chaos synchronization in noisy environment using nonlinear filtering and sliding mode control
International Nuclear Information System (INIS)
Behzad, Mehdi; Salarieh, Hassan; Alasty, Aria
2008-01-01
This paper presents an algorithm for synchronizing two different chaotic systems, using a combination of the extended Kalman filter and the sliding mode controller. It is assumed that the drive chaotic system has a random excitation with a stochastically chaotic behavior. Two different cases are considered in this study. At first it is assumed that all state variables of the drive system are available, i.e. complete state measurement, and a sliding mode controller is designed for synchronization. For the second case, it is assumed that the output of the drive system does not contain the whole state variables of the drive system, and it is also affected by some random noise. By combination of extended Kalman filter and the sliding mode control, a synchronizing control law is proposed. As a case study, the presented algorithm is applied to the Lur'e-Genesio chaotic systems as the drive-response dynamic systems. Simulation results show the good performance of the algorithm in synchronizing the chaotic systems in presence of noisy environment
Small-signal model of a decoupled double synchronous reference frame current controller
DEFF Research Database (Denmark)
Dowlatabadi, Mohammadkazem Bakhshizadeh; Hjerrild, Jester; Kocewiak, Lukasz
2016-01-01
the dq signals are not dc anymore, and therefore, linearization cannot be done. In this paper a Decoupled Double Synchronous Frame PLL is used to eliminate the oscillations in the dq frame signals. The small signal model of this PLL including an unbalanced current controller is presented in this paper....
International Nuclear Information System (INIS)
Rodriguez, A.; De Leon, J.; Fridman, L.
2009-01-01
The reduced-order synchronization problem of two chaotic systems (master-slave) with different dimension and relative degree is considered. A control scheme based on a high-order sliding-mode observer-identifier and a feedback state controller is proposed, where the trajectories of slave can be synchronized with a canonical projection of the master. Thus, the reduced-order synchronization is achieved in spite of master/slave mismatches. Simulation results are provided in order to illustrate the performance of the proposed synchronization scheme.
A modular control architecture for real-time synchronous and asynchronous systems
International Nuclear Information System (INIS)
Butler, P.L.; Jones, J.P.
1993-01-01
This paper describes a control architecture for real-time control of complex robotic systems. The Modular Integrated Control Architecture (MICA), which is actually two complementary control systems, recognizes and exploits the differences between asynchronous and synchronous control. The asynchronous control system simulates shared memory on a heterogeneous network. For control information, a portable event-scheme is used. This scheme provides consistent interprocess coordination among multiple tasks on a number of distributed systems. The machines in the network can vary with respect to their native operating systems and the intemal representation of numbers they use. The synchronous control system is needed for tight real-time control of complex electromechanical systems such as robot manipulators, and the system uses multiple processors at a specified rate. Both the synchronous and asynchronous portions of MICA have been developed to be extremely modular. MICA presents a simple programming model to code developers and also considers the needs of system integrators and maintainers. MICA has been used successfully in a complex robotics project involving a mobile 7-degree-of-freedom manipulator in a heterogeneous network with a body of software totaling over 100,000 lines of code. MICA has also been used in another robotics system, controlling a commercial long-reach manipulator
Mathematical Modelling and Predictive Control of Permanent Magnet Synchronous Motor Drives
Czech Academy of Sciences Publication Activity Database
Belda, Květoslav
2013-01-01
Roč. 2, č. 4 (2013), s. 114-120 ISSN 1805-3386 R&D Projects: GA ČR(CZ) GAP102/11/0437 Institutional support: RVO:67985556 Keywords : Permanent magnet synchronous motor * mathematical modelling * discrete predictive control * multistep explicit control law * square-root optimization Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2014/AS/belda-0422285.pdf
Seyed A. Taher; Reza Hematti; Ali Abdolalipour; Majid Nemati
2008-01-01
The Static Synchronous Compensator (STATCOM) provides shunt compensation in similar way to the Static VAR Compensator (SVC) but utilizes a voltage source converter rather than capacitors and reactor. In practice systems use simple Proportional-Integral (PI) controllers for control of STATCOM. However, since the PI control parameters were usually tuned based on classical or trial-and-error approaches, they were incapable of obtaining good dynamic performance for a wide range of operation condi...
Naggar H. Saad; Ahmed A. El-Sattar; Mohamed I. Marei
2016-01-01
The main challenges of wind energy conversion systems (WECS) are to maximize the energy capture from the wind and injecting reactive power during the fault. This paper presents a current controlled matrix converter to interface Permanent Magnet Synchronous Generators (PMSG) based WECS with the grid. To achieve fast dynamic response with reduced current ripples, a hysteresis current control is utilized. The proposed control system decouples the active and reactive components of the PMSG curren...
Chaos synchronization and chaotization of complex chaotic systems in series form by optimal control
International Nuclear Information System (INIS)
Ge Zhengming; Yang, C.-H.
2009-01-01
By the method of quadratic optimum control, a quadratic optimal regulator is used for synchronizing two complex chaotic systems in series form. By this method the least error with less control energy is achieved, and the optimization on both energy and error is realized synthetically. The simulation results of two Quantum-CNN chaos systems in series form prove the effectiveness of this method. Finally, chaotization of the system is given by optimal control.
Versatile synchronized real-time MEG hardware controller for large-scale fast data acquisition
Sun, Limin; Han, Menglai; Pratt, Kevin; Paulson, Douglas; Dinh, Christoph; Esch, Lorenz; Okada, Yoshio; Hämäläinen, Matti
2017-05-01
Versatile controllers for accurate, fast, and real-time synchronized acquisition of large-scale data are useful in many areas of science, engineering, and technology. Here, we describe the development of a controller software based on a technique called queued state machine for controlling the data acquisition (DAQ) hardware, continuously acquiring a large amount of data synchronized across a large number of channels (>400) at a fast rate (up to 20 kHz/channel) in real time, and interfacing with applications for real-time data analysis and display of electrophysiological data. This DAQ controller was developed specifically for a 384-channel pediatric whole-head magnetoencephalography (MEG) system, but its architecture is useful for wide applications. This controller running in a LabVIEW environment interfaces with microprocessors in the MEG sensor electronics to control their real-time operation. It also interfaces with a real-time MEG analysis software via transmission control protocol/internet protocol, to control the synchronous acquisition and transfer of the data in real time from >400 channels to acquisition and analysis workstations. The successful implementation of this controller for an MEG system with a large number of channels demonstrates the feasibility of employing the present architecture in several other applications.
Adaptive control of dynamical synchronization on evolving networks with noise disturbances
Yuan, Wu-Jie; Zhou, Jian-Fang; Sendiña-Nadal, Irene; Boccaletti, Stefano; Wang, Zhen
2018-02-01
In real-world networked systems, the underlying structure is often affected by external and internal unforeseen factors, making its evolution typically inaccessible. An adaptive strategy was introduced for maintaining synchronization on unpredictably evolving networks [Sorrentino and Ott, Phys. Rev. Lett. 100, 114101 (2008), 10.1103/PhysRevLett.100.114101], which yet does not consider the noise disturbances widely existing in networks' environments. We provide here strategies to control dynamical synchronization on slowly and unpredictably evolving networks subjected to noise disturbances which are observed at the node and at the communication channel level. With our strategy, the nodes' coupling strength is adaptively adjusted with the aim of controlling synchronization, and according only to their received signal and noise disturbances. We first provide a theoretical analysis of the control scheme by introducing an error potential function to seek for the minimization of the synchronization error. Then, we show numerical experiments which verify our theoretical results. In particular, it is found that our adaptive strategy is effective even for the case in which the dynamics of the uncontrolled network would be explosive (i.e., the states of all the nodes would diverge to infinity).
Energy Technology Data Exchange (ETDEWEB)
Cai Shuiming, E-mail: caishuiming2008@yahoo.com.c [Department of Mathematics, Shanghai University, Shanghai 200444 (China); Institute of System Biology, Shanghai University, Shanghai 200444 (China); Hao Junjun [Institute of System Biology, Shanghai University, Shanghai 200444 (China); He, Qinbin [Department of Mathematics, Taizhou University, Linhai 317000 (China); Institute of System Biology, Shanghai University, Shanghai 200444 (China); Liu Zengrong, E-mail: zrongliu@126.co [Department of Mathematics, Shanghai University, Shanghai 200444 (China) and Institute of System Biology, Shanghai University, Shanghai 200444 (China)
2011-05-09
The problem of synchronization for a class of complex delayed dynamical networks via pinning periodically intermittent control is considered in this Letter. Some novel and useful exponential synchronization criteria are obtained by utilizing the methods which are different from the techniques employed in the existing works, and the derived results are less conservative. Especially, the traditional assumptions on control width and time delays are released in our results. Moreover, a pinning scheme deciding what nodes should be chosen as pinned candidates and how many nodes are needed to be pinned for a fixed coupling strength is provided. A Barabasi-Albert network example is finally given to illustrate the effectiveness of the theoretical results. - Highlights: Pinning control problem of complex networks via intermittent control is investigated. The traditional assumptions on control width and time delays are removed. A scheme deciding what nodes should be chosen as pinned candidates is proposed. A scheme deciding how many nodes are needed to be pinned is provided.
Using sampled-data feedback control and linear feedback synchronization in a new hyperchaotic system
International Nuclear Information System (INIS)
Zhao Junchan; Lu Junan
2008-01-01
This paper investigates control and synchronization of a new hyperchaotic system which was proposed by [Chen A, Lu J-A, Lue J, Yu S. Generating hyperchaotic Lue attractor via state feedback control. Physica A 2006;364:103-10]. Firstly, we give different sampled-data feedback control schemes with the variation of system parameter d. Specifically, we only use one controller to drive the system to the origin when d element of (-0.35, 0), and use two controllers if d element of [0, 1.3]. Next, we combine PC method with linear feedback approach to realize synchronization, and derive similar conclusions with varying d. Numerical simulations are also given to validate the proposed approaches
Directory of Open Access Journals (Sweden)
Tat-Bao-Thien Nguyen
2014-01-01
Full Text Available In this paper, based on fuzzy neural networks, we develop an adaptive sliding mode controller for chaos suppression and tracking control in a chaotic permanent magnet synchronous motor (PMSM drive system. The proposed controller consists of two parts. The first is an adaptive sliding mode controller which employs a fuzzy neural network to estimate the unknown nonlinear models for constructing the sliding mode controller. The second is a compensational controller which adaptively compensates estimation errors. For stability analysis, the Lyapunov synthesis approach is used to ensure the stability of controlled systems. Finally, simulation results are provided to verify the validity and superiority of the proposed method.
Unit Template Synchronous Reference Frame Theory Based Control Algorithm for DSTATCOM
Bangarraju, J.; Rajagopal, V.; Jayalaxmi, A.
2014-04-01
This article proposes new and simplified unit templates instead of standard phase locked loop (PLL) for Synchronous Reference Frame Theory Control Algorithm (SRFT). The extraction of synchronizing components (sinθ and cosθ) for parks and inverse parks transformation using standard PLL takes more execution time. This execution time in control algorithm delays the extraction of reference source current generation. The standard PLL not only takes more execution time but also increases the reactive power burden on the Distributed Static Compensator (DSTATCOM). This work proposes a unit template based SRFT control algorithm for four-leg insulated gate bipolar transistor based voltage source converter for DSTATCOM in distribution systems. This will reduce the execution time and reactive power burden on the DSTATCOM. The proposed DSTATCOM suppress harmonics, regulates the terminal voltage along with neutral current compensation. The DSTATCOM in distribution systems with proposed control algorithm is modeled and simulated using MATLAB using SIMULINK and Simpower systems toolboxes.
Chaos control and synchronization of two neurons exposed to ELF external electric field
International Nuclear Information System (INIS)
Wang Jiang; Zhang Ting; Che Yanqiu
2007-01-01
Chaos control and synchronization of two unidirectional coupled neurons exposed to ELF electrical field via nonlinear control technique is investigated. Based on results of space-time characteristics of trans-membrane voltage, the variation of cell trans-membrane voltage exposed to extremely low frequency (ELF) electric field is analyzed. The dynamical behaviors of the modified Hodgkin-Huxley (HH) model are identified under the periodic ELF electric field using both analytical and numerical analysis. Then, using the results of the analysis, a nonlinear feedback linearization control scheme and a modified adaptive control strategy are designed to synchronize the two unidirectional coupled neurons and stabilize the chaotic trajectory of the slave system to desired periodic orbit of the master system. The simulation results demonstrated the efficiency of the proposed algorithms
An integrated system for synchronous culture of animal cells under controlled conditions.
Mendoza-Pérez, Elena; Hernández, Vanessa; Palomares, Laura A; Serrato, José A
2016-01-01
The cell cycle has fundamental effects on cell cultures and their products. Tools to synchronize cultured cells allow the study of cellular physiology and metabolism at particular cell cycle phases. However, cells are most often arrested by methods that alter their homeostasis and are then cultivated in poorly controlled environments. Cell behavior could then be affected by the synchronization method and culture conditions used, and not just by the particular cell cycle phase under study. Moreover, only a few viable cells are recovered. Here, we designed an integrated system where a large number of cells from a controlled bioreactor culture is separated by centrifugal elutriation at high viabilities. In contrast to current elutriation methods, cells are injected directly from a bioreactor into an injection loop, allowing the introduction of a large number of cells into the separation chamber without stressful centrifugation. A low pulsation peristaltic pump increases the stability of the elutriation chamber. Using this approach, a large number of healthy cells at each cell cycle phase were obtained, allowing their direct inoculation into fully instrumented bioreactors. Hybridoma cells synchronized and cultured in this system behaved as expected for a synchronous culture.
Cai, Zuowei; Huang, Lihong; Guo, Zhenyuan; Zhang, Lingling; Wan, Xuting
2015-08-01
This paper is concerned with the periodic synchronization problem for a general class of delayed neural networks (DNNs) with discontinuous neuron activation. One of the purposes is to analyze the problem of periodic orbits. To do so, we introduce new tools including inequality techniques and Kakutani's fixed point theorem of set-valued maps to derive the existence of periodic solution. Another purpose is to design a switching state-feedback control for realizing global exponential synchronization of the drive-response network system with periodic coefficients. Unlike the previous works on periodic synchronization of neural network, both the neuron activations and controllers in this paper are allowed to be discontinuous. Moreover, owing to the occurrence of delays in neuron signal, the neural network model is described by the functional differential equation. So we introduce extended Filippov-framework to deal with the basic issues of solutions for discontinuous DNNs. Finally, two examples and simulation experiments are given to illustrate the proposed method and main results which have an important instructional significance in the design of periodic synchronized DNNs circuits involving discontinuous or switching factors. Copyright © 2015 Elsevier Ltd. All rights reserved.
Generalized projective synchronization of chaotic systems via adaptive learning control
International Nuclear Information System (INIS)
Yun-Ping, Sun; Jun-Min, Li; Hui-Lin, Wang; Jiang-An, Wang
2010-01-01
In this paper, a learning control approach is applied to the generalized projective synchronisation (GPS) of different chaotic systems with unknown periodically time-varying parameters. Using the Lyapunov–Krasovskii functional stability theory, a differential-difference mixed parametric learning law and an adaptive learning control law are constructed to make the states of two different chaotic systems asymptotically synchronised. The scheme is successfully applied to the generalized projective synchronisation between the Lorenz system and Chen system. Moreover, numerical simulations results are used to verify the effectiveness of the proposed scheme. (general)
Noise controlled synchronization in potassium coupled neural models
DEFF Research Database (Denmark)
Postnov, Dmitry E; Ryazanova, Ludmila S; Zhirin, Roman A
2007-01-01
The paper applies biologically plausible models to investigate how noise input to small ensembles of neurons, coupled via the extracellular potassium concentration, can influence their firing patterns. Using the noise intensity and the volume of the extracellular space as control parameters, we...
Sensorless Control of PM Synchronous Motors and Brushless DC Motors
DEFF Research Database (Denmark)
Montesinos, D.; Galceran, Samuel; Blaabjerg, Frede
2005-01-01
This paper provides a review of the literature addressing sensorless operation methods of PM brushless machines. The methods explained are state-of-the-art of open and closed loop control strategies. The closed loop review includes those methods based on voltage and current measurements, those...
Synchronization and Desynchronizing Control Schemes for Supermarket Refrigeration Systems
DEFF Research Database (Denmark)
Larsen, Lars Finn Sloth; Thybo, Claus Thybo; Izadi-Zamanabadi, Roozbeh
2007-01-01
A supermarket refrigeration system is a hybrid system with switched nonlinear dynamics and discrete-valued input variables such as opening/closing of valves and start/stop of compressors. Practical and simulation studies have shown that the use of distributed hysteresis controllers to operate...
International Nuclear Information System (INIS)
Farivar, Faezeh; Aliyari Shoorehdeli, Mahdi; Nekoui, Mohammad Ali; Teshnehlab, Mohammad
2012-01-01
Highlights: ► A systematic procedure for GPS of unknown heavy chaotic gyroscope systems. ► Proposed methods are based on Lyapunov stability theory. ► Without calculating Lyapunov exponents and Eigen values of the Jacobian matrix. ► Capable to extend for a variety of chaotic systems. ► Useful for practical applications in the future. - Abstract: This paper proposes the chaos control and the generalized projective synchronization methods for heavy symmetric gyroscope systems via Gaussian radial basis adaptive variable structure control. Because of the nonlinear terms of the gyroscope system, the system exhibits chaotic motions. Occasionally, the extreme sensitivity to initial states in a system operating in chaotic mode can be very destructive to the system because of unpredictable behavior. In order to improve the performance of a dynamic system or avoid the chaotic phenomena, it is necessary to control a chaotic system with a periodic motion beneficial for working with a particular condition. As chaotic signals are usually broadband and noise like, synchronized chaotic systems can be used as cipher generators for secure communication. This paper presents chaos synchronization of two identical chaotic motions of symmetric gyroscopes. In this paper, the switching surfaces are adopted to ensure the stability of the error dynamics in variable structure control. Using the neural variable structure control technique, control laws are established which guarantees the chaos control and the generalized projective synchronization of unknown gyroscope systems. In the neural variable structure control, Gaussian radial basis functions are utilized to on-line estimate the system dynamic functions. Also, the adaptation laws of the on-line estimator are derived in the sense of Lyapunov function. Thus, the unknown gyro systems can be guaranteed to be asymptotically stable. Also, the proposed method can achieve the control objectives. Numerical simulations are presented to
KORKMAZ, Yılmaz; KORKMAZ, Fatih
2008-01-01
In industry, the loads driven by electrical motors require that the performances of motors and loads are compatible. In this study, a comparison of the performances of asynchronous motor and permanent magnet synchronous motor controlled by the same method which is compatible with the load is aimed. In order to do that the control of asynchronous motor and permanent magnet motor by direct torque method is simulated in MATLAB environment. In this simulation, the success of the accession times t...
Liu Yue; Zhou Shuo
2016-01-01
To improve the dynamic performance of permanent magnet synchronous motor(PMSM) drive system, a adaptive nonsingular terminal sliding model control((NTSMC) strategy was proposed. The proposed control strategy presents an adaptive variable-rated exponential reaching law which the L1 norm of state variables is introduced. Exponential and constant approach speed can adaptively adjust according to the state variables’ distance to the equilibrium position.The proposed scheme can shorten the reachin...
Yousefi-Talouki, Arzhang; Pescetto, Paolo; Pellegrino, Gian-Mario Luigi
2017-01-01
This paper proposes a sensorless direct flux vector control scheme for synchronous reluctance motor drives. Torque is controlled at constant switching frequency, via the closed loop regulation of the stator flux linkage vector and of the current component in quadrature with it, using the stator flux oriented reference frame. A hybrid flux and position observer combines back-electromotive force integration with pulsating voltage injection around zero speed. Around zero speed, the position obse...
A COMPENSATOR APPLICATION USING SYNCHRONOUS MOTOR WITH A PI CONTROLLER BASED ON PIC
Ramazan BAYINDIR; Alper GÖRGÜN
2009-01-01
In this paper, PI control of a synchronous motor has been realized by using a PIC 18F452 microcontroller and it has been worked as ohmic, inductive and capacitive with different excitation currents. Instead of solving integral operation of PI control which has difficulties with conversion to the digital system, summation of all error values of a defined time period are multiplied with the sampling period. Reference values of the PI algorithm are determined with Ziegler-Nicholas method. These ...
Kumar, Pawan; Parmananda, P.
2018-04-01
Experiments involving the Mercury Beating Heart (MBH) oscillator, exhibiting irregular (aperiodic) dynamics, are performed. In the first set of experiments, control over irregular dynamics of the MBH oscillator was obtained via a superimposed periodic voltage signal. These irregular (aperiodic) dynamics were recovered once the control was switched off. Subsequently, two MBH oscillators were coupled to attain synchronization of their aperiodic oscillations. Finally, two uncoupled MBH oscillators were subjected, repeatedly, to a common stochastic forcing, resulting in an enhancement of their mutual phase correlation.
Directory of Open Access Journals (Sweden)
Y. D. Filipchik
2011-01-01
Full Text Available The paper considers an impact of various methods for control of an exciting current pertaining to a synchronous generator on the nature of transient processes. A control algorithm for the exciting current in relation to changes in sliding and acceleration of a generator rotor has been proposed in the paper. The algorithm makes it possible to improve quality of the transient processes due to reduction of oscillation range concerning as an active power so a δ-angle as well.
Design of adaptive sliding mode control for synchronization Genesio–Tesi chaotic system
International Nuclear Information System (INIS)
Ghamati, Mina; Balochian, Saeed
2015-01-01
In this paper two adaptive sliding mode controls for synchronizing the state trajectories of the Genesio–Tesi system with unknown parameters and external disturbance are proposed. A switching surface is introduced and based on this switching surface, two adaptive sliding mode control schemes are presented to guarantee the occurrence of the sliding motion. The stability and robustness of the two proposed schemes are proved using Lyapunov stability theory. The effectiveness of our introduced schemes is provided by numerical simulations
Directory of Open Access Journals (Sweden)
Iosif SZEIDERT
2000-12-01
Full Text Available This paper presents two self-tuning control structures synthesized through the minimization of two criterion functions. It is described the computation methodology of the control laws, both being particularized for the case of the synchronous generator's excitation control. The parameters estimator is considered the recursive least square error (RLSE algorithm. In order to validate the considered control structures, two comparative study cases by computer simulation are presented.
Chaos control and synchronization for a special generalized Lorenz canonical system - The SM system
International Nuclear Information System (INIS)
Liao Xiaoxin; Xu, F.; Wang, P.; Yu Pei
2009-01-01
This paper presents some simple feedback control laws to study global stabilization and global synchronization for a special chaotic system described in the generalized Lorenz canonical form (GLCF) when τ = -1 (which, for convenience, we call Shimizu-Morioka system, or simply SM system). For an arbitrarily given equilibrium point, a simple feedback controller is designed to globally, exponentially stabilize the system, and reach globally exponent synchronization for two such systems. Based on the system's coefficients and the structure of the system, simple feedback control laws and corresponding Lyapunov functions are constructed. Because all conditions are obtained explicitly in terms of algebraic expressions, they are easy to be implemented and applied to real problems. Numerical simulation results are presented to verify the theoretical predictions.
International Nuclear Information System (INIS)
Balasubramaniam, P.; Kalpana, M.; Rakkiyappan, R.
2012-01-01
Fuzzy cellular neural networks (FCNNs) are special kinds of cellular neural networks (CNNs). Each cell in an FCNN contains fuzzy operating abilities. The entire network is governed by cellular computing laws. The design of FCNNs is based on fuzzy local rules. In this paper, a linear matrix inequality (LMI) approach for synchronization control of FCNNs with mixed delays is investigated. Mixed delays include discrete time-varying delays and unbounded distributed delays. A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network. By constructing the Lyapunov—Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LMIs. The controller can be easily obtained by solving the derived LMIs. A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method. (interdisciplinary physics and related areas of science and technology)
Computer controllable synchronous shifting of an automatic transmission
Davis, R.I.; Patil, P.B.
1989-08-08
A multiple forward speed automatic transmission produces its lowest forward speed ratio when a hydraulic clutch and hydraulic brake are disengaged and a one-way clutch connects a ring gear to the transmission casing. Second forward speed ratio results when the hydraulic clutch is engaged to connect the ring gear to the planetary carrier of a second gear set. Reverse drive and regenerative operation result when an hydraulic brake fixes the planetary and the direction of power flow is reversed. Various sensors produce signals representing the torque at the output of the transmission or drive wheels, the speed of the power source, and the hydraulic pressure applied to a clutch and brake. A control algorithm produces input data representing a commanded upshift, a commanded downshift, a commanded transmission output torque, and commanded power source speed. A microprocessor processes the inputs and produces a response to them in accordance with the execution of a control algorithm. Output or response signals cause selective engagement and disengagement of the clutch and brake at a rate that satisfies the requirements for a short gear ratio change and smooth torque transfer between the friction elements. 6 figs.
Synchronizing Spatiotemporal Chaos via a Composite Disturbance Observer-Based Sliding Mode Control
Directory of Open Access Journals (Sweden)
Congyan Chen
2014-01-01
Full Text Available The sliding mode control schemes are investigated to synchronize two spatiotemporal chaotic systems, which are two arrays of a large number of coupled chaotic oscillators. Firstly, sliding mode manifolds with the desired performance are designed. The asymptotic convergence to the origin of the synchronization errors is also proved. However, the terms from parameter fluctuations in equivalent controls are usually impossible to be measured directly. So we regard them as lumped disturbances, but, for practical application, it is difficult to obtain the upper bound of lumped disturbances in advance which often results in a conservative sliding mode control law with large control effort, causing a large amount of chattering. To reduce the chattering and improve the performance of the system, a disturbance observer is designed to estimate the lumped disturbances. A composite synchronization controller that consists of a sliding mode feedback part and a feedforward compensation part based on disturbance observer is developed. The numerical simulation results are presented to show the effectiveness of the proposed methods.
Implementation of IEEE-1588 timing and synchronization for ATCA control and data acquisition systems
Energy Technology Data Exchange (ETDEWEB)
Correia, Miguel, E-mail: miguelfc@lei.fis.uc.pt [Associacao EURATOM/IST, Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Lisboa (Portugal); Sousa, Jorge; Combo, Alvaro; Rodrigues, Antonio P.; Carvalho, Bernardo B.; Batista, Antonio J.N.; Goncalves, Bruno [Associacao EURATOM/IST, Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Lisboa (Portugal); Correia, Carlos M.B.A. [Grupo de Electronica e Instrumentacao do Centro de Instrumentacao, Dept. de Fisica, Universidade de Coimbra, Coimbra (Portugal); Varandas, Carlos A.F. [Associacao EURATOM/IST, Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Lisboa (Portugal)
2012-12-15
Highlights: Black-Right-Pointing-Pointer IEEE-1588 over Ethernet protocol is implemented for the synchronization of all clock signals of an ATCA AMC carrier module. Black-Right-Pointing-Pointer The ATCA hardware consists of an AMC quad-carrier main-board with PCI Express switching. Black-Right-Pointing-Pointer IEEE-1588 is to be implemented on a Virtex-6 FPGA. Black-Right-Pointing-Pointer Timing signals on the ATX-AMC4-PTP are managed and routed by a crosspoint-switch implemented on a Virtex-6 FPGA. Black-Right-Pointing-Pointer Each clock signal source may be independently located (on each of the AMC cards, RTM or ATCA backplane). - Abstract: Control and data acquisition (C and DA) systems for Fusion experiments are required to provide accurate timing and synchronization (T and S) signals to all of its components. IPFN adopted PICMG's Advanced Telecommunications Computing Architecture (ATCA) industry standard to develop C and DA instrumentation. ATCA was chosen not only for its high throughput characteristics but also for its high availability (HA) features which become of greater importance in steady-state operation scenarios. However, the specified ATCA clock and synchronization interface may be too limited for the timing and synchronization needs in advanced Physics experiments. Upcoming specification extensions, developed by the 'xTCA for Physics' workgroups, will contemplate, among others, a complementary timing specification, developed by the PICMG xTCA for Physics IO, Timing and Synchronization Technical Committee. The IEEE-1588 Precision Time Protocol (PTP) over Ethernet is one of the protocols, proposed by the Committee, aiming for precise synchronization of clocks in measurement and control systems, based on low jitter and slave-to-slave skew criteria. The paper presents an implementation of IEEE-1588 over Ethernet, in an ATCA hardware platform. The ATCA hardware consists of an Advanced Mezzanine Card (AMC) quad-carrier front board with PCI
Implementation of IEEE-1588 timing and synchronization for ATCA control and data acquisition systems
International Nuclear Information System (INIS)
Correia, Miguel; Sousa, Jorge; Combo, Álvaro; Rodrigues, António P.; Carvalho, Bernardo B.; Batista, António J.N.; Gonçalves, Bruno; Correia, Carlos M.B.A.; Varandas, Carlos A.F.
2012-01-01
Highlights: ► IEEE-1588 over Ethernet protocol is implemented for the synchronization of all clock signals of an ATCA AMC carrier module. ► The ATCA hardware consists of an AMC quad-carrier main-board with PCI Express switching. ► IEEE-1588 is to be implemented on a Virtex-6 FPGA. ► Timing signals on the ATX-AMC4-PTP are managed and routed by a crosspoint-switch implemented on a Virtex-6 FPGA. ► Each clock signal source may be independently located (on each of the AMC cards, RTM or ATCA backplane). - Abstract: Control and data acquisition (C and DA) systems for Fusion experiments are required to provide accurate timing and synchronization (T and S) signals to all of its components. IPFN adopted PICMG's Advanced Telecommunications Computing Architecture (ATCA) industry standard to develop C and DA instrumentation. ATCA was chosen not only for its high throughput characteristics but also for its high availability (HA) features which become of greater importance in steady-state operation scenarios. However, the specified ATCA clock and synchronization interface may be too limited for the timing and synchronization needs in advanced Physics experiments. Upcoming specification extensions, developed by the “xTCA for Physics” workgroups, will contemplate, among others, a complementary timing specification, developed by the PICMG xTCA for Physics IO, Timing and Synchronization Technical Committee. The IEEE-1588 Precision Time Protocol (PTP) over Ethernet is one of the protocols, proposed by the Committee, aiming for precise synchronization of clocks in measurement and control systems, based on low jitter and slave-to-slave skew criteria. The paper presents an implementation of IEEE-1588 over Ethernet, in an ATCA hardware platform. The ATCA hardware consists of an Advanced Mezzanine Card (AMC) quad-carrier front board with PCI Express switching. IEEE-1588 is to be implemented on a Virtex-6 FPGA. Ethernet connectivity with the remote master clock is located on
Farivar, Faezeh; Shoorehdeli, Mahdi Aliyari
2012-01-01
In this paper, fault tolerant synchronization of chaotic gyroscope systems versus external disturbances via Lyapunov rule-based fuzzy control is investigated. Taking the general nature of faults in the slave system into account, a new synchronization scheme, namely, fault tolerant synchronization, is proposed, by which the synchronization can be achieved no matter whether the faults and disturbances occur or not. By making use of a slave observer and a Lyapunov rule-based fuzzy control, fault tolerant synchronization can be achieved. Two techniques are considered as control methods: classic Lyapunov-based control and Lyapunov rule-based fuzzy control. On the basis of Lyapunov stability theory and fuzzy rules, the nonlinear controller and some generic sufficient conditions for global asymptotic synchronization are obtained. The fuzzy rules are directly constructed subject to a common Lyapunov function such that the error dynamics of two identical chaotic motions of symmetric gyros satisfy stability in the Lyapunov sense. Two proposed methods are compared. The Lyapunov rule-based fuzzy control can compensate for the actuator faults and disturbances occurring in the slave system. Numerical simulation results demonstrate the validity and feasibility of the proposed method for fault tolerant synchronization. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.
Sensorless interior permanent magnet synchronous motor control with rotational inertia adjustment
Directory of Open Access Journals (Sweden)
Yongle Mao
2016-12-01
Full Text Available Mechanical model is generally required in high dynamic sensorless motor control schemes for zero phase lag estimation of rotor position and speed. However, the rotational inertia uncertainty will cause dynamic estimation errors, eventually resulting in performance deterioration of the sensorless control system. Therefore, this article proposes a high dynamic performance sensorless control strategy with online adjustment of the rotational inertia. Based on a synthetic back electromotive force model, the voltage equation of interior permanent magnet synchronous motor is transformed to that of an equivalent non-salient permanent magnet synchronous motor. Then, an extended nonlinear observer is designed for interior permanent magnet synchronous motor in the stator-fixed coordinate frame, with rotor position, speed and load torque simultaneously estimated. The effect of inaccurate rotational inertia on the estimation of rotor position and speed is investigated, and a novel rotational inertia adjustment approach that employs the gradient descent algorithm is proposed to suppress the dynamic estimation errors. The effectiveness of the proposed control strategy is demonstrated by experimental tests.
Unbalanced voltage control of virtual synchronous generator in isolated micro-grid
Cao, Y. Z.; Wang, H. N.; Chen, B.
2017-06-01
Virtual synchronous generator (VSG) control is recommended to stabilize the voltage and frequency in isolated micro-grid. However, common VSG control is challenged by widely used unbalance loads, and the linked unbalance voltage problem worsens the power quality of the micro-grid. In this paper, the mathematical model of VSG was presented. Based on the analysis of positive- and negative-sequence equivalent circuit of VSG, an approach was proposed to eliminate the negative-sequence voltage of VSG with unbalance loads. Delay cancellation method and PI controller were utilized to identify and suppress the negative-sequence voltages. Simulation results verify the feasibility of proposed control strategy.
Chen, Zhuo; Shi, Kaibo; Zhong, Shouming
2016-07-01
This paper investigates the synchronization problem for a class of complex delayed dynamical networks (CDDNs) by using sampled-data feedback control. First, an augmented Lyapunov-Krasovskii function (LKF) is constructed, which contains two new triple integral terms to reduce the conservativeness. Second, improved synchronization criteria are proposed by combining reciprocally convex technique with a novel class of integral inequalities, which can provide much tighter bounds than what the existing integral inequalities can produce. Third, the desired sampled-data controllers can be achieved by solving a set of linear matrix inequalities (LMIs). Finally, three numerical simulation examples are presented to demonstrate the effectiveness and advantages of the proposed results. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.
A COMPENSATOR APPLICATION USING SYNCHRONOUS MOTOR WITH A PI CONTROLLER BASED ON PIC
Directory of Open Access Journals (Sweden)
Ramazan BAYINDIR
2009-01-01
Full Text Available In this paper, PI control of a synchronous motor has been realized by using a PIC 18F452 microcontroller and it has been worked as ohmic, inductive and capacitive with different excitation currents. Instead of solving integral operation of PI control which has difficulties with conversion to the digital system, summation of all error values of a defined time period are multiplied with the sampling period. Reference values of the PI algorithm are determined with Ziegler-Nicholas method. These parameters are calculated into the microcontroller and changed according to the algorithm. In addition, this work designed to provide visualization for the users. Current, voltage and power factor data of the synchronous motor can be observed easily on the LCD instantly.
Mcconnell, W. J., Jr.
1979-01-01
Techniques for obtaining time synchronized (4D) approach control in the VALT research helicopter is described. Various 4D concepts and their compatibility with the existing VALT digital computer navigation and guidance system hardware and software are examined. Modifications to various techniques were investigated in order to take advantage of the unique operating characteristics of the helicopter in the terminal area. A 4D system is proposed, combining the direct to maneuver with the existing VALT curved path generation capability.
Field oriented control of permanent magnet synchronous motors with time constant adaption
International Nuclear Information System (INIS)
Afsharnia, S.; Vahedi, A.
2001-01-01
In this paper, initially, we present a method for on-line identifying of Permanent Magnet Synchronous Machine electrical parameters, then these parameters will be used in the vector control structure of motors. Simulation results show the efficiency of this method to parameters identifying of machine even in the presence of saturation, variation of temperature and etc. Because of simplicity and being economic, this method can be used by electro motors constructors to identify motor parameters for different operating points
Abuter, Roberto; Dembet, Roderick; Lacour, Sylvestre; di Lieto, Nicola; Woillez, Julien; Eisenhauer, Frank; Fedou, Pierre; Phan Duc, Than
2016-08-01
The new VLTI (Very Large Telescope Interferometer) 1 instrument GRAVITY5, 22, 23 is equipped with a fringe tracker16 able to stabilize the K-band fringes on six baselines at the same time. It has been designed to achieve a performance for average seeing conditions of a residual OPD (Optical Path Difference) lower than 300 nm with objects brighter than K = 10. The control loop implementing the tracking is composed of a four stage real time computer system compromising: a sensor where the detector pixels are read in and the OPD and GD (Group Delay) are calculated; a controller receiving the computed sensor quantities and producing commands for the piezo actuators; a concentrator which combines both the OPD commands with the real time tip/tilt corrections offloading them to the piezo actuator; and finally a Kalman15 parameter estimator. This last stage is used to monitor current measurements over a window of few seconds and estimate new values for the main Kalman15 control loop parameters. The hardware and software implementation of this design runs asynchronously and communicates the four computers for data transfer via the Reflective Memory Network3. With the purpose of improving the performance of the GRAVITY5, 23 fringe tracking16, 22 control loop, a deviation from the standard asynchronous communication mechanism has been proposed and implemented. This new scheme operates the four independent real time computers involved in the tracking loop synchronously using the Reflective Memory Interrupts2 as the coordination signal. This synchronous mechanism had the effect of reducing the total pure delay of the loop from 3.5 [ms] to 2.0 [ms] which then translates on a better stabilization of the fringes as the bandwidth of the system is substantially improved. This paper will explain in detail the real time architecture of the fringe tracker in both is synchronous and synchronous implementation. The achieved improvements on reducing the delay via this mechanism will be
Zhao, Yi; Fu, Fangfang; Wang, Jingyi; Feng, Jianwen; Zhang, Haiyu
2018-02-01
In this paper, a new control method named partial mixed impulsive control strategy is proposed to investigate the problem of exponential synchronization in mean square for a class of general hybrid-coupled delayed dynamical networks with both internal delay and coupling delay. The partial mixed impulsive effects in this strategy can be taken as local and time-varying, which means that they are not only injected into a fraction of nodes in the whole networks but also contain synchronizing and desynchronizing impulses at the same time. In addition, to be more realistic, a delayed coupling term involving the transmission delay and self-feedback delay is taken into account. By means of the Lyapunov method and the comparison principle for impulsive systems, several sufficient criteria are obtained to guarantee the global exponential synchronization in mean square of the dynamical network. The obtained criteria are closely related to the proportion of the controlled nodes, the strengths of mixed impulses, the impulsive intervals, the time delays and the topology structure of the networks. Finally, a numerical example is given to demonstrate the effectiveness of our results.
Linear-control-based synchronization of coexisting attractor networks with time delays
International Nuclear Information System (INIS)
Yun-Zhong, Song
2010-01-01
This paper introduces the concept of linear-control-based synchronization of coexisting attractor networks with time delays. Within the new framework, closed loop control for each dynamic node is realized through linear state feedback around its own arena in a decentralized way, where the feedback matrix is determined through consideration of the coordination of the node dynamics, the inner connected matrix and the outer connected matrix. Unlike previously existing results, the feedback gain matrix here is decoupled from the inner matrix; this not only guarantees the flexible choice of the gain matrix, but also leaves much space for inner matrix configuration. Synchronization of coexisting attractor networks with time delays is made possible in virtue of local interaction, which works in a distributed way between individual neighbours, and the linear feedback control for each node. Provided that the network is connected and balanced, synchronization will come true naturally, where theoretical proof is given via a Lyapunov function. For completeness, several illustrative examples are presented to further elucidate the novelty and efficacy of the proposed scheme. (general)
DEFF Research Database (Denmark)
Monfared, Mohammad; Golestan, Saeed; Guerrero, Josep M.
2014-01-01
Control of three-phase power converters in the synchronous reference frame is now a mature and well developed research topic. However, for single-phase converters, it is not as well-established as three-phase applications. This paper deals with the design of a synchronous reference frame multi......-loop control strategy for single phase inverter-based islanded distributed generation (DG) systems. The proposed controller uses a synchronous reference frame PI (SRFPI) controller to regulate the instantaneous output voltage, a capacitor current shaping loop in the stationary reference frame to provide active...... in the synchronous reference frame, it is not straightforward to fine-tune the control parameters and evaluate the stability of the whole closed loop system. To overcome this problem, the stationary reference frame equivalent of the voltage loop is derived. Then, a step-by-step systematic design procedure based...
Synchronous temperature rate control and apparatus for refrigeration with reduced energy consumption
Gomes, Alberto Regio; Keres, Stephen L.; Kuehl, Steven J.; Litch, Andrew D.; Richmond, Peter J.; Wu, Guolian
2015-09-22
A refrigerator appliance configuration, and associated methods of operation, for an appliance with a controller, a condenser, at least one evaporator, a compressor, and two refrigeration compartments. The configuration may be equipped with a variable-speed or variable-capacity compressor, variable speed evaporator or compartment fans, a damper, and/or a dual-temperature evaporator with a valve system to control flow of refrigerant through one or more pressure reduction devices. The controller, by operation of the compressor, fans, damper and/or valve system, depending on the appliance configuration, synchronizes alternating cycles of cooling each compartment to a temperature approximately equal to the compartment set point temperature.
Maximum Torque per Ampere Control of Permanent Magnet Synchronous Motor Using Genetic Algorithm
Directory of Open Access Journals (Sweden)
Mohammad Rezaei
2011-08-01
Full Text Available Permanent magnet synchronous motor (PMSM drives have many advantages over other drives, i.e. high efficiency and high power density. Particularly, PMSMs are epoch-making and are intensively studied among researchers, scientists and engineers. This paper deals with a novel high performance controller based on genetic algorithm. The scheme allows the motor to be driven with maximum torque per ampere characteristic. In this paper assuming an appropriate fitness function, the optimum values for d-axis current of motor set points at each time are found and then applied to the controller. Simulation results show the successful operation of the proposed controller.
Chaubey, Neeraj; Mukherjee, S.; Sen, A.
2017-10-01
An experimental investigation of the influence of an external periodic forcing on the synchronization dynamics of two inductively coupled plasma sources is reported. The driven response of the coupled system is found to have a rich structure in the parameter space of the frequency and the amplitude of the external driver. In particular, there is a strong impact on the nature of the phase-flip transitions between anti-phase and in-phase synchronized states of the system and the frequency bifurcation structure of the collective states. The external driver provides a convenient tool for accessing various collective states of the system and controlling the collective dynamics of the two coupled systems through a proper choice of its frequency and amplitude. Our experimental results are qualitatively supported by numerical simulation results from a theoretical model of two environmentally coupled van der Pol equations, one of which is also driven externally.
Synchronization and Control of Halo-Chaos in Beam Transport Network with Small World Topology
International Nuclear Information System (INIS)
Liu Qiang; Fang Jinqing; Li Yong
2007-01-01
The synchronous conditions of two kinds of the small-world (SW) network are studied. The small world topology can affect on dynamical behaviors of the beam transport network (BTN) largely, if the BTN is constructed with the SW topology, the global linear coupling and special linear feedback can realize the synchronization control of beam halo-chaos as well as periodic state in the BTN with the SW topology, respectively. This important result can provide an effective way for the experimental study and the engineering design of the BTN in the high-current accelerator driven radioactive clean nuclear power systems, and may have potential use in prospective applications for halo-chaos secure communication.
Torque control of synchronous and induction generators for variable speed operation of wind turbines
Energy Technology Data Exchange (ETDEWEB)
Carlson, Ola; Ulen, E. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Electric Power Engineering
1996-12-01
The aim of this paper is to investigate variable speed electrical systems. Synchronous generators with diode rectifiers and line-commutated thyristor converters are compared with induction generators with force commutated transistor converters and scalar control. The system characteristics are examined regarding possible speed of response (bandwidth) of the torque control, including the sensitivity to disturbances for the drive train and also the possibility to get damping of the drive train resonance. Analyses, simulations and laboratory tests with a 40 kW machine set-up have been performed. The investigation shows that the system with synchronous generator is well suited for wind power applications. A rapid standard DC-current regulator is included in the torque control and can be used for damping of the resonance. The torque control has a bandwidth up to about 3 Hz and the DC-voltage controller up to about 1 Hz. The system with induction generator with scalar control (no transformations) is more difficult to control. A linear approach is only possible up to about 1.5 Hz. In this region it turns out that the behaviour can be visualized as an added inertia on the generator side that can be rather big. 4 refs, 9 figs
Current harmonics elimination control method for six-phase PM synchronous motor drives.
Yuan, Lei; Chen, Ming-liang; Shen, Jian-qing; Xiao, Fei
2015-11-01
To reduce the undesired 5th and 7th stator harmonic current in the six-phase permanent magnet synchronous motor (PMSM), an improved vector control algorithm was proposed based on vector space decomposition (VSD) transformation method, which can control the fundamental and harmonic subspace separately. To improve the traditional VSD technology, a novel synchronous rotating coordinate transformation matrix was presented in this paper, and only using the traditional PI controller in d-q subspace can meet the non-static difference adjustment, the controller parameter design method is given by employing internal model principle. Moreover, the current PI controller parallel with resonant controller is employed in x-y subspace to realize the specific 5th and 7th harmonic component compensation. In addition, a new six-phase SVPWM algorithm based on VSD transformation theory is also proposed. Simulation and experimental results verify the effectiveness of current decoupling vector controller. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.
DEFF Research Database (Denmark)
Kamchevska, Valerija; Cristofori, Valentina; Da Ros, Francesco
2016-01-01
We propose and demonstrate an algorithm that allows for automatic synchronization of SDN-controlled all-optical TDM switching nodes connected in a ring network. We experimentally show successful WDM-SDM transmission of data bursts between all ring nodes.......We propose and demonstrate an algorithm that allows for automatic synchronization of SDN-controlled all-optical TDM switching nodes connected in a ring network. We experimentally show successful WDM-SDM transmission of data bursts between all ring nodes....
International Nuclear Information System (INIS)
Ge Zhengming; Chang Chingming; Chen Yensheng
2006-01-01
Anti-control of chaos of single time scale brushless dc motors (BLDCM) and chaos synchronization of different order systems are studied in this paper. By addition of an external nonlinear term, we can obtain anti-control of chaos. Then, by addition of the coupling terms, by the use of Lyapunov stability theorem and by the linearization of the error dynamics, chaos synchronization between a third-order BLDCM and a second-order Duffing system are presented
International Nuclear Information System (INIS)
Jing, Wang; Zhen-Yu, Tan; Xi-Kui, Ma; Jin-Feng, Gao
2009-01-01
A novel adaptive observer-based control scheme is presented for synchronization and suppression of a class of uncertain chaotic system. First, an adaptive observer based on an orthogonal neural network is designed. Subsequently, the sliding mode controllers via the proposed adaptive observer are proposed for synchronization and suppression of the uncertain chaotic systems. Theoretical analysis and numerical simulation show the effectiveness of the proposed scheme. (general)
Energy Technology Data Exchange (ETDEWEB)
Aliprantis, D.C.; Papathanassiou, S.A.; Papadopoulos, M.P.; Kladas, A.G. [Purdue University, Electrical and Computer Engineering, West Lafayette, IN (United States)
2000-08-01
In this paper the operation of a variable-speed, stall regulated wind turbine equipped with a permanent magnet synchronous generator (PMSG) is examined. The emphasis is placed on the analysis of the electric part of the system, i.e. the electrical generator, the power electronics converters and the control. The operational characteristics of the machine are investigated through a series of computer simulations and the speed control system is designed to maximize the power output and achieve a smooth torque and power profile. (orig.)
Direct Torque Control System for Permanent Magnet Synchronous Machine with Fuzzy Speed Pi Regulator
Nabti, K.; Abed, K.; Benalla, H.
2008-06-01
The Permanent Magnet Synchronous Machine (PMSM) speed regulation with a conventional PI regulator reduces the speed control precision, increase the torque fluctuation, and consequentially low performances of the whole system. With utilisation of fuzzy logic method, this paper presents the self adaptation of conventional PI regulator parameters Kp and Ki (proportional and integral coefficients respectively), using to regulate the speed in Direct Torque Control strategy (DTC). The ripples of both torque and flux are reduced remarkable, small overshooting and good dynamic of the speed and torque. Simulation results verify the proposed method validity.
Quantized Synchronization of Chaotic Neural Networks With Scheduled Output Feedback Control.
Wan, Ying; Cao, Jinde; Wen, Guanghui
In this paper, the synchronization problem of master-slave chaotic neural networks with remote sensors, quantization process, and communication time delays is investigated. The information communication channel between the master chaotic neural network and slave chaotic neural network consists of several remote sensors, with each sensor able to access only partial knowledge of output information of the master neural network. At each sampling instants, each sensor updates its own measurement and only one sensor is scheduled to transmit its latest information to the controller's side in order to update the control inputs for the slave neural network. Thus, such communication process and control strategy are much more energy-saving comparing with the traditional point-to-point scheme. Sufficient conditions for output feedback control gain matrix, allowable length of sampling intervals, and upper bound of network-induced delays are derived to ensure the quantized synchronization of master-slave chaotic neural networks. Lastly, Chua's circuit system and 4-D Hopfield neural network are simulated to validate the effectiveness of the main results.In this paper, the synchronization problem of master-slave chaotic neural networks with remote sensors, quantization process, and communication time delays is investigated. The information communication channel between the master chaotic neural network and slave chaotic neural network consists of several remote sensors, with each sensor able to access only partial knowledge of output information of the master neural network. At each sampling instants, each sensor updates its own measurement and only one sensor is scheduled to transmit its latest information to the controller's side in order to update the control inputs for the slave neural network. Thus, such communication process and control strategy are much more energy-saving comparing with the traditional point-to-point scheme. Sufficient conditions for output feedback control
Synchronization of a modified Chua's circuit system via adaptive sliding mode control
International Nuclear Information System (INIS)
Yan, J.-J.; Lin, J.-S.; Liao, T.-L.
2008-01-01
This study addresses the adaptive synchronization of a modified Chua's circuit system with both unknown system parameters and the nonlinearity in the control input. An adaptive switching surface is newly adopted such that it becomes easy to ensure the stability of the error dynamics in the sliding mode. Based on this adaptive switching surface, an adaptive sliding mode controller (ASMC) is derived to guarantee the occurrence of the sliding motion, even when the system is undergoing input nonlinearity. This method can also be easily extended to a general class of Chua's circuits. An illustrative example is given to show the applicability of the proposed ASMC design
Synchronization in material flow networks with biologically inspired self-organized control
Energy Technology Data Exchange (ETDEWEB)
Donner, Reik; Laemmer, Stefan [TU Dresden (Germany); Helbing, Dirk [ETH Zuerich (Switzerland)
2009-07-01
The efficient operation of material flows in traffic or production networks is a subject of broad economic interest. Traditional centralized as well as decentralized approaches to operating material flow networks are known to have severe disadvantages. As an alternative approach that may help to overcome these problems, we propose a simple self-organization mechanism of conflicting flows that is inspired by oscillatory phenomena of pedestrian or animal counter-flows at bottlenecks. As a result, one may observe a synchronization of the switching dynamics at different intersections in the network. For regular grid topologies, we find different synchronization regimes depending on the inertia of the switching from one service state to the next one. In order to test the robustness of our corresponding observations, we study how the detailed properties of the network as well as dynamic feedbacks between the relevant state variables affect the degree of achievable synchronization and the resulting performance of the network. Our results yield an improved understanding of the conditions that have to be present for efficiently operating material flow networks by a decentralized control, which is of paramount importance for future implementations in real-world traffic or production systems.
Directory of Open Access Journals (Sweden)
Wang Ting
2014-01-01
Full Text Available Motivated by the importance of the clock synchronization in wireless sensor networks (WSNs, this paper proposes a new research approach and model approach, which quantitatively analyzes clock synchronization from the perspective of modern control theory. Two kinds of control strategies are used as examples to analyze the effect of the control strategy on clock synchronization from different perspectives, namely, the single-step optimal control and the LQG global optimal control. The proposed method establishes a state space model for clock relationship, thus making dimension extension and parameter identification easier, and is robust to changes under the condition of node failures and new nodes. And through the design of different control strategies and performance index functions, the method can satisfy various requirements of the synchronization precision, convergence speed, energy consumption and the computational complexity, and so on. Finally, the simulations show that the synchronization accuracy of the proposed method is higher than that of the existing protocol, and the former convergence speed of the synchronization error is faster.
Synchronicity from Synchronized Chaos
Directory of Open Access Journals (Sweden)
Gregory S. Duane
2015-03-01
Full Text Available The synchronization of loosely-coupled chaotic oscillators, a phenomenon investigated intensively for the last two decades, may realize the philosophical concept of “synchronicity”—the commonplace notion that related eventsmysteriously occur at the same time. When extended to continuous media and/or large discrete arrays, and when general (non-identical correspondences are considered between states, intermittent synchronous relationships indeed become ubiquitous. Meaningful synchronicity follows naturally if meaningful events are identified with coherent structures, defined by internal synchronization between remote degrees of freedom; a condition that has been posited as necessary for synchronizability with an external system. The important case of synchronization between mind and matter is realized if mind is analogized to a computer model, synchronizing with a sporadically observed system, as in meteorological data assimilation. Evidence for the ubiquity of synchronization is reviewed along with recent proposals that: (1 synchronization of different models of the same objective process may be an expeditious route to improved computational modeling and may also describe the functioning of conscious brains; and (2 the nonlocality in quantum phenomena implied by Bell’s theorem may be explained in a variety of deterministic (hidden variable interpretations if the quantum world resides on a generalized synchronization “manifold”.
International Nuclear Information System (INIS)
Da-Zhong, Ma; Hua-Guang, Zhang; Zhan-Shan, Wang; Jian, Feng
2010-01-01
In this paper the fault tolerant synchronization of two chaotic systems based on fuzzy model and sample data is investigated. The problem of fault tolerant synchronization is formulated to study the global asymptotical stability of the error system with the fuzzy sampled-data controller which contains a state feedback controller and a fault compensator. The synchronization can be achieved no matter whether the fault occurs or not. To investigate the stability of the error system and facilitate the design of the fuzzy sampled-data controller, a Takagi–Sugeno (T–S) fuzzy model is employed to represent the chaotic system dynamics. To acquire good performance and produce a less conservative analysis result, a new parameter-dependent Lyapunov–Krasovksii functional and a relaxed stabilization technique are considered. The stability conditions based on linear matrix inequality are obtained to achieve the fault tolerant synchronization of the chaotic systems. Finally, a numerical simulation is shown to verify the results. (general)
Morimoto, Shigeo; Nakamura, Tomohiko; Takeda, Yoji
This paper proposes the sensorless output power maximization control of the wind generation system. A permanent magnet synchronous generator (PMSG) is used as a variable speed generator in the proposed system. The generator torque is suitably controlled according to the generator speed and thus the power from a wind turbine settles down on the maximum power point by the proposed MPPT control method, where the information of wind velocity is not required. Moreover, the maximum available generated power is obtained by the optimum current vector control. The current vector of PMSG is optimally controlled according to the generator speed and the required torque in order to minimize the losses of PMSG considering the voltage and current constraints. The proposed wind power generation system can be achieved without mechanical sensors such as a wind velocity detector and a position sensor. Several experimental results show the effectiveness of the proposed control method.
Directory of Open Access Journals (Sweden)
Guangping Zhuo
2016-12-01
Full Text Available The subject of this paper pertains to sliding mode control and its application in nonlinear electrical power systems as seen in wind energy conversion systems. Due to the robustness in dealing with unmodeled system dynamics, sliding mode control has been widely used in electrical power system applications. This paper presents first and high order sliding mode control schemes for permanent magnet synchronous generator-based wind energy conversion systems. The application of these methods for control using dynamic models of the d-axis and q-axis currents, as well as those of the high speed shaft rotational speed show a high level of efficiency in power extraction from a varying wind resource. Computer simulation results have shown the efficacy of the proposed sliding mode control approaches.
Sensorless Speed Control of Permanent Magnet Synchronous Motors by Neural Network Algorithm
Directory of Open Access Journals (Sweden)
Ming-Shyan Wang
2014-01-01
Full Text Available The sliding mode control has the merits with respect to the variation of the disturbance and robustness. In this paper, the sensorless sliding-mode observer with least mean squared error approach for permanent magnet synchronous motor (PMSM to detect the rotor position by counter electromotive force and then compute motor speed is designed and implemented. In addition, the neural network control is also used to compensate the PI gain tuning to increase the speed accuracy without regarding the errors of the current measurement and motor noise. In this paper, a digital signal processor TMS320F2812 utilizes its high-speed ADC module to get current feedback information and thus to estimate the rotor position and takes advantage of the built-in modules to achieve SVPWM current control so that the senseless speed control will be accomplished. The correctness and effectiveness of the proposed control system will be verified from the experimental results.
Development of Digital Control for High Power Permanent-Magnet Synchronous Motor Drives
Directory of Open Access Journals (Sweden)
Ming-Hung Chen
2014-01-01
Full Text Available This paper is concerned with the development of digital control system for high power permanent-magnet synchronous motor (PMSM to yield good speed regulation, low current harmonic, and stable output speed. The design of controller is conducted by digitizing the mathematical model of PMSM using impulse invariance technique. The predicted current estimator, which is insensitive to motor feedback currents, is proposed to function under stationary frame for harmonic current suppression. In the AC/DC power converter, mathematical model and dc-link voltage limit of the three-phase switch-mode rectifier are derived. In addition, a current controller under synchronous frame is introduced to reduce the current harmonics and increase the power factor on the input side. A digital control system for 75 kW PMSM is realized with digital signal processor (R5F5630EDDFP. Experimental results indicate that the total harmonic distortion of current is reduced from 4.1% to 2.8% for 50 kW output power by the proposed predicted current estimator technique.
Li, Xiaofan; Fang, Jian-An; Li, Huiyuan
2017-09-01
This paper investigates master-slave exponential synchronization for a class of complex-valued memristor-based neural networks with time-varying delays via discontinuous impulsive control. Firstly, the master and slave complex-valued memristor-based neural networks with time-varying delays are translated to two real-valued memristor-based neural networks. Secondly, an impulsive control law is constructed and utilized to guarantee master-slave exponential synchronization of the neural networks. Thirdly, the master-slave synchronization problems are transformed into the stability problems of the master-slave error system. By employing linear matrix inequality (LMI) technique and constructing an appropriate Lyapunov-Krasovskii functional, some sufficient synchronization criteria are derived. Finally, a numerical simulation is provided to illustrate the effectiveness of the obtained theoretical results. Copyright © 2017 Elsevier Ltd. All rights reserved.
Numerical assessment of efficiency and control stability of an HTS synchronous motor
International Nuclear Information System (INIS)
Xian Wei; Yuan Weijia; Coombs, T A
2010-01-01
A high temperature superconducting (HTS) permanent magnet synchronous motor (PMSM) is designed and developed in Cambridge University. It is expected to become cost competitive with the conventional PMSM owing to its high efficiency, high power density, high torque density, etc. The structure and parameters of HTS PMSM are detailed. Both AC losses by transport current and applied filed in stator armature winding of HTS PMSM are also analyzed. Computed and simulated results of the characteristics of the HTS PMSM and conventional PMSM are compared. The improvement on stability of direct torque control (DTC) on the HTS PMSM is estimated, and proved by simulation on Matlab/Simulink.
Impulsive control for permanent magnet synchronous motors with uncertainties: LMI approach
International Nuclear Information System (INIS)
Dong, Li; Shi-Long, Wang; Xiao-Hong, Zhang; Dan, Yang
2010-01-01
A permanent magnet synchronous motor (PMSM) may have chaotic behaviours under certain working conditions, especially for uncertain values of parameters, which threatens the security and stability of motor-driven operation. Hence, it is important to study methods of controlling or suppressing chaos in PMSMs. In this paper, the stability of a PMSM with parameter uncertainties is investigated. After uncertain matrices which represent the variable system parameters are formulated through matrix analysis, a novel asymptotical stability criterion is established by employing the method of Lyapunov functions and linear matrix inequality technology. An example is also given to illustrate the effectiveness of our results. (general)
Directory of Open Access Journals (Sweden)
Hui Li
2014-04-01
Full Text Available Three-motor synchronous coordination system is a MI-MO nonlinear and complex control system. And it often works in poor working condition. Advanced control strategies are required to improve the control performance of the system and to achieve the decoupling between main motor speed and tension. Cerebellar Model Articulation Controller coupled with Active Disturbance Rejection Control (CMAC-ADRC control strategy is proposed. The speed of the main motor and tensions between two motors is decoupled by extended state observer (ESO in ADRC. ESO in ADRC is used to compensate internal and external disturbances of the system online. And the anti interference of the system is improved by ESO. And the same time the control model is optimized. Feedforward control is implemented by the adoption of CMAC neural network controller. And control precision of the system is improved in reason of CMAC. The overshoot of the system can be reduced without affecting the dynamic response of the system by the use of CMAC-ADRC. The simulation results show that: the CMAC- ADRC control strategy is better than the traditional PID control strategy. And CMAC-ADRC control strategy can achieve the decoupling between speed and tension. The control system using CMAC-ADRC have strong anti-interference ability and small regulate time and small overshoot. The magnitude of the system response incited by the interference using CMAC-ADRC is smaller than the system using conventional PID control 6.43 %. And the recovery time of the system with CMAC-ADRC is shorter than the system with traditional PID control 0.18 seconds. And the triangular wave tracking error of the system with CMAC-ADRC is smaller than the system with conventional PID control 0.24 rad/min. Thus the CMAC-ADRC control strategy is a good control strategy and is able to fit three-motor synchronous coordinated control.
Implementation of time synchronized cryogenics control system network architecture for SST-1
Energy Technology Data Exchange (ETDEWEB)
Patel, Rakesh J., E-mail: rpatel@ipr.res.in; Mahesuria, Gaurang; Panchal, Pradip; Panchal, Rohit; Sonara, Dasarath; Tanna, Vipul; Pradhan, Subrata
2016-11-15
Highlights: • SST-1 cryogenics sub-systems are 1.3 kW HRL, LN2 distribution system, current feeders system and 80 K booster system. • GUI developed in SCADA and control program developed in PLC for automation of the above sub-systems. • Implemented the cryogenics control system network to communicate all systems to InSQL server. • InSQL server configured for real time centralized process data acquisition from all connected sub-systems control nodes. • Acquired the process parameters coming from different systems at same time stamp. - Abstract: Under the SST-1 mission mandate, the several cryogenic sub-systems have been developed, upgraded and procured in prior to the SST-1 operation. New developments include 80 K Bubble type thermal shields, LN2 distribution system, LN2 booster system and current feeders system (CFS).Graphical User Interface (GUI) program developed in Wonderware SCADA and control logic program developed in Schneider make PLC for the above sub-systems. Industrial SQL server (InSQL) configured for centralized storage of real time process data coming from various control nodes of cryogenics sub-systems. The cryogenics control system network for communicating all cryogenics sub-system control nodes to InSQL server for centralized data storage and time synchronization among cryogenic sub-systems with centralized InSQL server is successfully implemented. Due to implemented time synchronization among sub-systems control nodes, it is possible to analyze the process parameters coming from different sub-systems at same time stamp. This paper describes the overview of implemented cryogenics control system network architecture for real time cryogenic process data monitor, storage and retrieval.
Directory of Open Access Journals (Sweden)
Xuan Wu
2015-01-01
Full Text Available In order to control the permanent-magnet synchronous motor system (PMSM with different disturbances and nonlinearity, an improved current control algorithm for the PMSM systems using recursive model predictive control (RMPC is developed in this paper. As the conventional MPC has to be computed online, its iterative computational procedure needs long computing time. To enhance computational speed, a recursive method based on recursive Levenberg-Marquardt algorithm (RLMA and iterative learning control (ILC is introduced to solve the learning issue in MPC. RMPC is able to significantly decrease the computation cost of traditional MPC in the PMSM system. The effectiveness of the proposed algorithm has been verified by simulation and experimental results.
Directory of Open Access Journals (Sweden)
Seyed Mohammad Ali Zanjani
2011-10-01
Full Text Available With the rapid technology advancement in control processes, electric utilities are experiencing more demanding requirements on the power quality from the large industrial power consumers. For achieved this purpose use of FACTS devices. One of kind compensator is D-Statcom, using in distribution system for conquest of power quality problem. This paper presents system modeling and control design techniques of distribution static synchronous compensator. For reach an optimal design, using a hybride state-feedback and d-q control systems. Using direct sampling on network parameter, than conventional control system, as well as fast dynamic responses are achieved. The derived simulations are tried to verify the result of this paper.
Gomes, Alberto Regio; Keres, Stephen L.; Kuehl, Stephen J.; Litch, Andrew D.; Richmond, Peter J.; Wu, Guolian
2015-09-22
A refrigerator appliance configuration, and associated methods of operation, for an appliance with a controller, a condenser, at least one evaporator, a compressor, and two refrigeration compartments. The configuration may be equipped with a variable-speed or variable-capacity compressor, variable speed evaporator or compartment fans, a damper and/or a dual-temperature evaporator with a valve system to control flow of refrigerant through one or more pressure reduction devices. The controller, by operation of the compressor, fans, damper and/or valve system, depending on the appliance configuration, controls the cooling rate in one or both compartments to synchronize, alternating cycles of cooling the compartments to their set point temperatures.
Moutinho, Filipe de Carvalho
2016-01-01
This book describes a model-based development approach for globally-asynchronous locally-synchronous distributed embedded controllers. This approach uses Petri nets as modeling formalism to create platform and network independent models supporting the use of design automation tools. To support this development approach, the Petri nets class in use is extended with time-domains and asynchronous-channels. The authors’ approach uses models not only providing a better understanding of the distributed controller and improving the communication among the stakeholders, but also to be ready to support the entire lifecycle, including the simulation, the verification (using model-checking tools), the implementation (relying on automatic code generators), and the deployment of the distributed controller into specific platforms. Uses a graphical and intuitive modeling formalism supported by design automation tools; Enables verification, ensuring that the distributed controller was correctly specified; Provides flex...
LPV Control for the Full Region Operation of a Wind Turbine Integrated with Synchronous Generator
Directory of Open Access Journals (Sweden)
Guoyan Cao
2015-01-01
Full Text Available Wind turbine conversion systems require feedback control to achieve reliable wind turbine operation and stable current supply. A robust linear parameter varying (LPV controller is proposed to reduce the structural loads and improve the power extraction of a horizontal axis wind turbine operating in both the partial load and the full load regions. The LPV model is derived from the wind turbine state space models extracted by FAST (fatigue, aerodynamics, structural, and turbulence code linearization at different operating points. In order to assure a smooth transition between the two regions, appropriate frequency-dependent varying scaling parametric weighting functions are designed in the LPV control structure. The solution of a set of linear matrix inequalities (LMIs leads to the LPV controller. A synchronous generator model is connected with the closed LPV control loop for examining the electrical subsystem performance obtained by an inner speed control loop. Simulation results of a 1.5 MW horizontal axis wind turbine model on the FAST platform illustrates the benefit of the LPV control and demonstrates the advantages of this proposed LPV controller, when compared with a traditional gain scheduling PI control and prior LPV control configurations. Enhanced structural load mitigation, improved power extraction, and good current performance were obtained from the proposed LPV control.
Adaptive PIF Control for Permanent Magnet Synchronous Motors Based on GPC
Directory of Open Access Journals (Sweden)
Shaowu Lu
2012-12-01
Full Text Available To enhance the control performance of permanent magnet synchronous motors (PMSMs, a generalized predictive control (GPC-based proportional integral feedforward (PIF controller is proposed for the speed control system. In this new approach, firstly, based on the online identification of controlled model parameters, a simplified GPC law supplies the PIF controller with suitable control parameters according to the uncertainties in the operating conditions. Secondly, the speed reference curve for PMSMs is usually required to be continuous and continuously differentiable according to the general servo system design requirements, so the adaptation of the speed reference is discussed in details in this paper. Hence, the performance of the speed control system using a GPC-based PIF controller is improved for tracking some specified signals. The main motivation of this paper is the extension of GPC law to replace the traditional PI or PIF controllers in industrial applications. The efficacy and usefulness of the proposed controller are verified through experimental results.
LPV Control for the Full Region Operation of a Wind Turbine Integrated with Synchronous Generator
Grigoriadis, Karolos M.; Nyanteh, Yaw D.
2015-01-01
Wind turbine conversion systems require feedback control to achieve reliable wind turbine operation and stable current supply. A robust linear parameter varying (LPV) controller is proposed to reduce the structural loads and improve the power extraction of a horizontal axis wind turbine operating in both the partial load and the full load regions. The LPV model is derived from the wind turbine state space models extracted by FAST (fatigue, aerodynamics, structural, and turbulence) code linearization at different operating points. In order to assure a smooth transition between the two regions, appropriate frequency-dependent varying scaling parametric weighting functions are designed in the LPV control structure. The solution of a set of linear matrix inequalities (LMIs) leads to the LPV controller. A synchronous generator model is connected with the closed LPV control loop for examining the electrical subsystem performance obtained by an inner speed control loop. Simulation results of a 1.5 MW horizontal axis wind turbine model on the FAST platform illustrates the benefit of the LPV control and demonstrates the advantages of this proposed LPV controller, when compared with a traditional gain scheduling PI control and prior LPV control configurations. Enhanced structural load mitigation, improved power extraction, and good current performance were obtained from the proposed LPV control. PMID:25884036
Improved inertial control for permanent magnet synchronous generator wind turbine generators
Energy Technology Data Exchange (ETDEWEB)
Wu, Ziping; Gao, Wenzhong; Wang, Xiao; Kang, Moses; Hwang, Min; Kang, Yong Cheol; Gevogian, Vahan; Muljadi, Eduard
2016-05-31
With increasing integrations of large-scale systems based on permanent magnet synchronous generator wind turbine generators (PMSG-WTGs), the overall inertial response of a power system will tend to deteriorate as a result of the decoupling of rotor speed and grid frequency through the power converter as well as the scheduled retirement of conventional synchronous generators. Thus, PMSG-WTGs can provide value to an electric grid by contributing to the system's inertial response through the inherent kinetic energy stored in their rotating masses and fast power converter control. In this study, an improved inertial control method based on the maximum power point tracking operation curve is introduced to enhance the overall frequency support capability of PMSG-WTGs in the case of large supply-demand imbalances. Moreover, this method is implemented in the CART2-PMSG integrated model in MATLAB/Simulink to investigate its impact on the wind turbine's structural loads during the inertial response process. Simulation results indicate that the proposed method can effectively reduce the frequency nadir, arrest the rate of change of frequency, and alleviate the secondary frequency dip while imposing no negative impact on the major mechanical components of the wind turbine.
Directory of Open Access Journals (Sweden)
Liu Yue
2016-01-01
Full Text Available To improve the dynamic performance of permanent magnet synchronous motor(PMSM drive system, a adaptive nonsingular terminal sliding model control((NTSMC strategy was proposed. The proposed control strategy presents an adaptive variable-rated exponential reaching law which the L1 norm of state variables is introduced. Exponential and constant approach speed can adaptively adjust according to the state variables’ distance to the equilibrium position.The proposed scheme can shorten the reaching time and weaken system chatting. The method was applied to the PMSM speed servo system, and compared with the traditional terminal-sliding-mode regulator and PI regulator. Simulation results show that the proposed control strategy can improve dynamic, steady performance and robustness.
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Naggar H. Saad
2016-05-01
Full Text Available The main challenges of wind energy conversion systems (WECS are to maximize the energy capture from the wind and injecting reactive power during the fault. This paper presents a current controlled matrix converter to interface Permanent Magnet Synchronous Generators (PMSG based WECS with the grid. To achieve fast dynamic response with reduced current ripples, a hysteresis current control is utilized. The proposed control system decouples the active and reactive components of the PMSG current to extract the maximum power from the wind at a given wind velocity and to inject reactive power to the grid. Reactive power injection during the fault satisfying the grid-codes requirement. The proposed WECS has been modeled and simulated using PSCAD/EMTDC software package.
Xiong, Wenjun; Patel, Ragini; Cao, Jinde; Zheng, Wei Xing
In this brief, our purpose is to apply asynchronous and intermittent sampled-data control methods to achieve the synchronization of hierarchical time-varying neural networks. The asynchronous and intermittent sampled-data controllers are proposed for two reasons: 1) the controllers may not transmit the control information simultaneously and 2) the controllers cannot always exist at any time . The synchronization is then discussed for a kind of hierarchical time-varying neural networks based on the asynchronous and intermittent sampled-data controllers. Finally, the simulation results are given to illustrate the usefulness of the developed criteria.In this brief, our purpose is to apply asynchronous and intermittent sampled-data control methods to achieve the synchronization of hierarchical time-varying neural networks. The asynchronous and intermittent sampled-data controllers are proposed for two reasons: 1) the controllers may not transmit the control information simultaneously and 2) the controllers cannot always exist at any time . The synchronization is then discussed for a kind of hierarchical time-varying neural networks based on the asynchronous and intermittent sampled-data controllers. Finally, the simulation results are given to illustrate the usefulness of the developed criteria.
Control-Oriented Model of a Generating Set Comprising a Diesel Engine and a Synchronous Generator
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Mutaz Tuffaha
2015-10-01
Full Text Available A generating set (Genset comprises a prime mover such as a Diesel Engine, and a synchronous generator. The most important controllers of such systems are the speed governor to regulate the engine or shaft speed and the automatic voltage regulator (AVR to regulate the terminal voltage. The speed governor is a PID controller that uses the difference between the speed and its desired value as a feedback signal to change the fuel mass input by changing the fuel rack position. AVR is also a PID that uses the difference between the terminal voltage of the generator and its desired value, and changes it by manipulating the voltage of the field excitation circuit. Thus, the two controllers act separately. That is to say, if the speed varies from the desired value, the speed governor will react, while the AVR will not react as long as the voltage is stable, and vice versa. In this work, a control-oriented model is suggested for a Genset, and then a controller, that regulates the shaft speed and the terminal voltage, is designed by feedback linearisation. The proposed controller has two inputs: the fuel mass and the field circuit voltage. Simulations show that the proposed controller makes the two inputs act, simultaneously. Thus, any change of the speed e.g., forces the two input controls to react, in contrast to the ordinary PID controllers. Further, we discuss the robustness of the proposed controller to uncertainties and time delay.
Energy Technology Data Exchange (ETDEWEB)
Zielinski, J.S.
2006-07-15
The X-ray free-electron laser X-FEL that is being planned at the DESY research center in cooperation with European partners will produce high-intensity ultra-short X-ray flashes with the properties of laser light. This new light source, which can only be described in terms of superlatives, will open up a whole range of new possibilities for the natural sciences. It could also offer very promising opportunities for industrial users. SIMCON (SIMulator and CONtroller) is the project of the fast, low latency digital controller dedicated to the LLRF1 system in VUV FEL experiment It is being developed by the ELHEP2 group in the Institute of Electronic Systems at Warsaw University of Technology. The main purpose of the project is to create a controller to stabilize the vector sum of fields in cavities of one cryo-module in the experiment. The device can be also used as the simulator of the cavity and test bench for other devices. The synchronic, optical link project was made for the accelerator X-FEL laser TESLA, the LLRF control system experiment at DESY, Hamburg. The control and diagnostic data is transmitted up to 2.5Gbit/s through a plastic fiber in a distance up to a few hundred meters. The link is synchronized once after power up, and never resynchronized when data is transmitted with maximum speed. The one way link bit error rate is less then 10{sup -15}. The transceiver component written in VHDL that works in the dedicated Altera registered Stratix registered GX FPGA circuit. During the work in the PERG laboratory a 2,5Gbit/s serial link with the long vector parallel interface transceiver was created. Long-Data-Vector transceiver transmits 16bit vector each 8ns with 120ns latency. (orig.)
International Nuclear Information System (INIS)
Zielinski, J.S.
2006-05-01
The X-ray free-electron laser X-FEL that is being planned at the DESY research center in cooperation with European partners will produce high-intensity ultra-short X-ray flashes with the properties of laser light. This new light source, which can only be described in terms of superlatives, will open up a whole range of new possibilities for the natural sciences. It could also offer very promising opportunities for industrial users. SIMCON (SIMulator and CONtroller) is the project of the fast, low latency digital controller dedicated to the LLRF1 system in VUV FEL experiment It is being developed by the ELHEP2 group in the Institute of Electronic Systems at Warsaw University of Technology. The main purpose of the project is to create a controller to stabilize the vector sum of fields in cavities of one cryo-module in the experiment. The device can be also used as the simulator of the cavity and test bench for other devices. The synchronic, optical link project was made for the accelerator X-FEL laser TESLA, the LLRF control system experiment at DESY, Hamburg. The control and diagnostic data is transmitted up to 2.5Gbit/s through a plastic fiber in a distance up to a few hundred meters. The link is synchronized once after power up, and never resynchronized when data is transmitted with maximum speed. The one way link bit error rate is less then 10 -15 . The transceiver component written in VHDL that works in the dedicated Altera registered Stratix registered GX FPGA circuit. During the work in the PERG laboratory a 2,5Gbit/s serial link with the long vector parallel interface transceiver was created. Long-Data-Vector transceiver transmits 16bit vector each 8ns with 120ns latency. (orig.)
Yahyazadeh, Meisam; Ranjbar Noei, Abolfazl; Ghaderi, Reza
2011-04-01
This paper defines a new surface in an active sliding mode to synchronize two chaotic systems with parametric uncertainty. To verify the capability of the proposed scheme, signals are also contaminated by measurement noise. The integral acting surface produces a dynamics for error, where the appropriate eigenvalues are easily assigned. Using this surface, calculation of parameters of the controller becomes simpler than the classical alternative. A sufficient condition, as a guideline of the designated procedure, is dedicated to provide a robust stability of the error dynamics. Finally, a simulation study is performed to verify the robustness and effectiveness of the proposed control strategy. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.
Application of Quadratic Linearization for the Control of Permanent Magnet Synchronous Motor
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Parvathy Ayalur Krishnamoorthy
2011-01-01
Full Text Available Many of the existing control methods for the permanent magnet synchronous motor (PMSM either deal with steady state models or consider dynamic models under particular cases. A dynamic model of the PM machine allows powerful control-theoretic techniques such as linearization to be applied to the system. Existing exact feedback linearization of dynamic model of PMSM suffers from singularity issues. In this paper, we propose a quadratic linearization approach for PMSM based on the approximate linearization technique which does not introduce singularities. A MATLAB simulation is used to verify the effectiveness of the linearization technique proposed. Also, to account for higher-order and unmodelled dynamics of PMSM, tuning of the linearizing transformation is proposed and verified using simulation.
High-Order Sliding Mode-Based Synchronous Control of a Novel Stair-Climbing Wheelchair Robot
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Juanxiu Liu
2015-01-01
Full Text Available For the attitude control of a novel stair-climbing wheelchair with inertial uncertainties and external disturbance torques, a new synchronous control method is proposed via combing high-order sliding mode control techniques with cross-coupling techniques. For this purpose, a proper controller is designed, which can improve the performance of the system under conditions of uncertainties and torque perturbations and also can guarantee the synchronization of the system. Firstly, a robust high-order sliding mode control law is designed to track the desired position trajectories effectively. Secondly, considering the coordination of the multiple joints, a high-order sliding mode synchronization controller is designed to reduce the synchronization errors and tracking errors based on the controller designed previously. Stability of the closed-loop system is proved by Lyapunov theory. The simulation is performed by MATLAB to verify the effectiveness of the proposed controller. By comparing the simulation results of two controllers, it is obvious that the proposed scheme has better performance and stronger robustness.
FPA Tuned Fuzzy Logic Controlled Synchronous Buck Converter for a Wave/SC Energy System
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SAHIN, E.
2017-02-01
Full Text Available This paper presents a flower pollination algorithm (FPA tuned fuzzy logic controlled (FLC synchronous buck converter (SBC for an integrated wave/ supercapacitor (SC hybrid energy system. In order to compensate the irregular wave effects on electrical side of the wave energy converter (WEC, a SC unit charged by solar panels is connected in parallel to the WEC system and a SBC is controlled to provide more reliable and stable voltage to the DC load. In order to test the performance of the designed FLC, a classical proportional-integral-derivative (PID controller is also employed. Both of the controllers are optimized by FPA which is a pretty new optimization algorithm and a well-known optimization algorithm of which particle swarm optimization (PSO to minimize the integral of time weighted absolute error (ITAE performance index. Also, the other error-based objective functions are considered. The entire energy system and controllers are developed in Matlab/Simulink and realized experimentally. Real time applications are done through DS1104 Controller Board. The simulation and experimental results show that FPA tuned fuzzy logic controller provides lower value performance indices than conventional PID controller by reducing output voltage sags and swells of the wave/SC energy system.
Direct torque control of permanent magnet synchronous machines - analysis and implementation
Energy Technology Data Exchange (ETDEWEB)
Luukko, J.
2000-07-01
The direct torque control (DTC) has become an accepted vector control method beside the current vector control. The DTC was first applied to asynchronous machines, and has later been applied also to synchronous machines. This thesis analyses the application of the DTC to permanent magnet synchronous machines (PMSM). In order to take the full advantage of the DTC, the PMSM has to be properly dimensioned. Therefore the effect of the motor parameters is analysed taking the control principle into account. Based on the analysis, a parameter selection procedure is presented. The analysis and the selection procedure utilize nonlinear optimization methods. The key element of a direct torque controlled drive is the estimation of the stator flux linkage. Different estimation methods - a combination of current and voltage models and improved integration methods - are analysed. The effect of an incorrect measured rotor angle in the current model is analysed and an error detection and compensation method is presented. The dynamic performance of an earlier presented sensorless flux estimation method is made better by improving the dynamic performance of the lowpass filter used and by adapting the correction of the flux linkage to torque changes. A method for the estimation of the initial angle of the rotor is presented. The,method is based on measuring the inductance of the machine in several directions and fitting the measurements into a model. The model is nonlinear with respect to the rotor angle and therefore a nonlinear least squares optimization method is needed in the procedure. A commonly used current vector control scheme is the minimum current control. In the DTC the stator flux linkage reference is usually kept constant. Achieving the minimum current requires the control of the reference. An on-line method to perform the minimization of the current by controlling the stator flux linkage reference is presented. Also, the control of the reference above the base speed is
Hou, Huazhou; Zhang, Qingling
2016-11-01
In this paper we investigate the finite-time synchronization for second-order multi-agent system via pinning exponent sliding mode control. Firstly, for the nonlinear multi-agent system, differential mean value theorem is employed to transfer the nonlinear system into linear system, then, by pinning only one node in the system with novel exponent sliding mode control, we can achieve synchronization in finite time. Secondly, considering the 3-DOF helicopter system with nonlinear dynamics and disturbances, the novel exponent sliding mode control protocol is applied to only one node to achieve the synchronization. Finally, the simulation results show the effectiveness and the advantages of the proposed method. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.
Yuan, Manman; Wang, Weiping; Luo, Xiong; Li, Lixiang; Kurths, Jürgen; Wang, Xiao
2018-03-01
This paper is concerned with the exponential lag function projective synchronization of memristive multidirectional associative memory neural networks (MMAMNNs). First, we propose a new model of MMAMNNs with mixed time-varying delays. In the proposed approach, the mixed delays include time-varying discrete delays and distributed time delays. Second, we design two kinds of hybrid controllers. Traditional control methods lack the capability of reflecting variable synaptic weights. In this paper, the controllers are carefully designed to confirm the process of different types of synchronization in the MMAMNNs. Third, sufficient criteria guaranteeing the synchronization of system are derived based on the derive-response concept. Finally, the effectiveness of the proposed mechanism is validated with numerical experiments.
DEFF Research Database (Denmark)
Agarlita, Sorin-Christian; Fatu, M.; Tutelea, L. N.
2010-01-01
This paper presents a novel, hybrid, motion sensorless control of an axially laminated anisotropic (ALA) reluctance synchronous machine (RSM). By separately controlling Id and Iq currents with the reference currents Id*, Iq* being held constant, and ramping the reference frequency, the motor starts...
Transient and dynamic control of a variable speed wind turbine with synchronous generator
Energy Technology Data Exchange (ETDEWEB)
Jauch, Clemens [Riso National Laboratory, Wind Energy Department, PO Box 49, DK 4000 Roskilde, (Denmark)
2007-02-14
In this article, a controller for dynamic and transient control of a variable speed wind turbine with a full-scale converter-connected high-speed synchronous generator is presented. First, the phenomenon of drive train oscillations in wind turbines with full-scale converter-connected generators is discussed. Based on this discussion, a controller is presented that dampens these oscillations without impacting on the power that the wind turbine injects into the grid. Since wind turbines are increasingly demanded to take over power system stabilizing and control tasks, the presented wind turbine design is further enhanced to support the grid in transient grid events. A controller is designed that allows the wind turbine to ride through transient grid faults. Since such faults often cause power system oscillations, another controller is added that enables the turbine to participate in the damping of such oscillations. It is concluded that the controllers presented keep the wind turbine stable under any operating conditions, and that they are capable of adding substantial damping to the power system. (Author).
Kota, Venkata Reddy; Vinnakoti, Sudheer
2017-12-01
Today, maintaining Power Quality (PQ) is very important in the growing competent world. With new equipments and devices, new challenges are also being put before power system operators. Unified Power Quality Conditioner (UPQC) is proposed to mitigate many power quality problems and to improve the performance of the power system. In this paper, an UPQC with Fuzzy Logic controller for capacitor voltage balancing is proposed in Synchronous Reference Frame (SRF) based control with Modified Phased Locked Loop (MPLL). The proposed controller with SRF-MPLL based control is tested under non-linear and unbalanced load conditions. The system is developed in Matlab/Simulink and its performance is analyzed under various conditions like non-linear, unbalanced load and polluted supply voltage including voltage sag/swells. Active and reactive power flow in the system, power factor and %THD of voltages and currents before and after compensation are also analyzed in this work. Results prove the applicability of the proposed scheme for power quality improvement. It is observed that the fuzzy controller gives better performance than PI controller with faster capacitor voltage balancing and also improves the dynamic performance of the system.
Q-S synchronization in 3D Henon-like map and generalized Henon map via a scalar controller
International Nuclear Information System (INIS)
Yan Zhenya
2005-01-01
In this Letter, a generalized, systematic and automatic backstepping scheme is developed to investigate the Q-S synchronization of two identical 3a discrete-time dynamical systems and two different 3D discrete-time dynamical systems. With the aid of symbolic-numeric computation, we use the proposed scheme to illustrate chaos synchronization between two identical 3D generalized Henon map and Q-S synchronization between two different 3D generalized Henon map and Henon-like map via a scalar controller, respectively. Moreover numerical simulations are used to verify the effectiveness of the proposed scheme. In addition, the scheme can be also applied to investigate the tracking problem in the discrete-time systems and to generate automatically the scalar controller in computer with the aid of symbolic-numeric computation
Directory of Open Access Journals (Sweden)
Xingjian Wang
2017-10-01
Full Text Available Moving towards the more electric aircraft (MEA, a hybrid actuator configuration provides an opportunity to introduce electromechanical actuator (EMA into primary flight control. In the hybrid actuation system (HAS, an electro-hydraulic servo actuator (EHSA and an EMA operate on the same control surface. In order to solve force fighting problem in HAS, this paper proposes a novel linear extended state observer (LESO-based motion synchronization control method. To cope with the problem of unavailability of the state signals required by the motion synchronization controller, LESO is designed for EHSA and EMA to observe the state variables. Based on the observed states of LESO, motion synchronization controllers could enable EHSA and EMA to simultaneously track the desired motion trajectories. Additionally, nonlinearities, uncertainties and unknown disturbances as well as the coupling term between EHSA and EMA can be estimated and compensated by using the extended state of the proposed LESO. Finally, comparative simulation results indicate that the proposed LESO-based motion synchronization controller could reduce significant force fighting between EHSA and EMA.
Reduction of Sub-synchronous Resonances with D-FACTS Devices using intelligent Control
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Zahra Amini
2016-06-01
Full Text Available When a turbine–generator set connect to a long transmission line, may results side effects such as Sub-Synchronous Resonances (SSR. The capabilities of the Distributed Static Series Compensator (DSSC as a member of the family of D-FACTS can be used to reduce these SSR. To achieve this desired goal, the fuzzy controller, Particle Swarm Optimization (PSO and artificial neural network is used to control of the DSSC. Particle swarm optimization is designed Based on the Conventional Damping Controller (CDC and fuzzy logic is designed based on damping controller (FLBDC and damping control based on artificial neural network trained using the fast pace of changes has been designed. Stability of the system is analysed by simulations in the time domain with performance index (PI. All simulations are done using Matlab / Simulink software. Case studies show that proposed algorithms can reduce SSR in the system.All simulations are done using Matlab / Simulink software. Case studies show that proposed algorithms can reduce SSR in the system.
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Pedro Roncero-Sànchez
2014-04-01
Full Text Available Electric power systems are among the greatest achievements of the last century. Today, important issues, such as an ever-increasing demand, the flexible and reliable integration of distributed generation or a growth in disturbing loads, must be borne in mind. In this context, smart grids play a key role, allowing better efficiency of power systems. Power electronics provides solutions to the aforementioned matters, since it allows various energy sources to be integrated into smart grids. Nevertheless, the design of the various control schemes that are necessary for the correct operation of the power-electronic interface is a very important issue that must always be taken into consideration. This paper deals with the design of the control system of a distribution static synchronous compensator (DSTATCOM based on flying-capacitor multilevel converters. The control system is tailored to compensate for both voltage sags by means of reactive-power injection and voltage imbalances caused by unbalanced loads. The design of the overall control is carried out by using the root-locus and frequency-response techniques, improving both the transient response and the steady-state error of the closed-loop system. Simulation results obtained using PSCADTM/EMTDCTM (Manitoba Hydro International Ltd., Commerce Drive, Winnipeg, MB, Canada show the resultant voltage regulation.
Resonant power converter with dead-time control of synchronous rectification circuit
DEFF Research Database (Denmark)
2017-01-01
The invention relates in a first aspect to a resonant power converter comprising a synchronous rectifier for supplying a DC output voltage. The synchronous rectifier is configured for alternatingly connecting a resonant output voltage to positive and negative DC output nodes via first and second...
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Vaidyanathan Sundarapandian
2016-12-01
Full Text Available This research work announces an eleven-term novel 4-D hyperchaotic system with two quadratic nonlinearities. We describe the qualitative properties of the novel 4-D hyperchaotic system and illustrate their phase portraits. We show that the novel 4-D hyperchaotic system has two unstable equilibrium points. The novel 4-D hyperchaotic system has the Lyapunov exponents L1 = 3.1575, L2 = 0.3035, L3 = 0 and L4 = −33.4180. The Kaplan-Yorke dimension of this novel hyperchaotic system is found as DKY = 3.1026. Since the sum of the Lyapunov exponents of the novel hyperchaotic system is negative, we deduce that the novel hyperchaotic system is dissipative. Next, an adaptive controller is designed to stabilize the novel 4-D hyperchaotic system with unknown system parameters. Moreover, an adaptive controller is designed to achieve global hyperchaos synchronization of the identical novel 4-D hyperchaotic systems with unknown system parameters. The adaptive control results are established using Lyapunov stability theory. MATLAB simulations are depicted to illustrate all the main results derived in this research work.
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Qixin Zhu
2014-10-01
Full Text Available For the problems of buffeting and phase delay in traditional rotor detection in sensorless vector control of permanent magnet synchronous motor (PMSM, the Sigmoid function is proposed to replace sign function and the approach of piecewise linearization is proposed to compensate phase delay. To the problem that the output of traditional low pass filter contains high- order harmonic, two-stage filter including traditional low-pass filter and Kalman filter is proposed in this paper. Based on the output of traditional first-order low-pass filter, the Kalman filter is used to get modified back-EMF. The phase-locked loop control of rotor position is adopted to estimate motor position and speed. A Matlab/Simulink simulation model of PMSM position servo control system is established. The simulation analysis of the new sliding mode observer’s back-EMF detection, position and speed estimation, load disturbance and dynamic process are carried out respectively. Simulation results verify feasibility of the new sliding mode observer algorithm.
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Dongbin Lu
2014-01-01
Full Text Available The permanent magnet synchronous motor (PMSM has high efficiency and high torque density. Field oriented control (FOC is usually used in the motor to achieve maximum efficiency control. In the electric vehicle (EV application, the PMSM efficiency model, combined with the EV and road load system model, is used to study the optimal energy-saving control strategy, which is significant for the economic operation of EVs. With the help of GPS, IMU, and other information technologies, the road conditions can be measured in advance. Based on this information, the optimal velocity of the EV driven by PMSM can be obtained through the analytical algorithm according to the efficiency model of PMSM and the vehicle dynamic model in simple road conditions. In complex road conditions, considering the dynamic characteristics, the economic operating velocity trajectory of the EV can be obtained through the dynamic programming (DP algorithm. Simulation and experimental results show that the minimum energy consumption and global energy optimization can be achieved when the EV operates in the economic operation area.
Khanzadeh, Alireza; Pourgholi, Mahdi
2016-08-01
In the conventional chaos synchronization methods, the time at which two chaotic systems are synchronized, is usually unknown and depends on initial conditions. In this work based on Lyapunov stability theory a sliding mode controller with time-varying switching surfaces is proposed to achieve chaos synchronization at a pre-specified time for the first time. The proposed controller is able to synchronize chaotic systems precisely at any time when we want. Moreover, by choosing the time-varying switching surfaces in a way that the reaching phase is eliminated, the synchronization becomes robust to uncertainties and exogenous disturbances. Simulation results are presented to show the effectiveness of the proposed method of stabilizing and synchronizing chaotic systems with complete robustness to uncertainty and disturbances exactly at a pre-specified time.
International Nuclear Information System (INIS)
Khanzadeh, Alireza; Pourgholi, Mahdi
2016-01-01
In the conventional chaos synchronization methods, the time at which two chaotic systems are synchronized, is usually unknown and depends on initial conditions. In this work based on Lyapunov stability theory a sliding mode controller with time-varying switching surfaces is proposed to achieve chaos synchronization at a pre-specified time for the first time. The proposed controller is able to synchronize chaotic systems precisely at any time when we want. Moreover, by choosing the time-varying switching surfaces in a way that the reaching phase is eliminated, the synchronization becomes robust to uncertainties and exogenous disturbances. Simulation results are presented to show the effectiveness of the proposed method of stabilizing and synchronizing chaotic systems with complete robustness to uncertainty and disturbances exactly at a pre-specified time. (paper)
PREFACE: International Conference on Control and Synchronization of Dynamical Systems (CSDS-2005)
Pisarchik, Alexander N.
2005-01-01
This volume of Journal of Physics: Conference Series contains selected articles by the participants at the International Conference on Control and Synchronization of Dynamical Systems (CSDS-2005) organized by Centro de Investigaciones en Optica (CIO) in cooperation with the Society for Industrial and Applied Mathematics (SIAM), which was held in Leon, Guanajuato, Mexico on 4-7 October 2005. CSDS-2005 featured the latest research in nonlinear dynamics concentrating on the theory of control and synchronization of complex systems and its applications in different areas of science and engineering, including optics, electronics, mechanics, chemistry, medicine, economy, communication, etc. The conference brought together leading researchers, both theoreticians and experimentalists, from different fields of science and provided an excellent opportunity for sharing ideas and problems among specialists in controlling dynamical systems and synchronization. The meeting served a dual purpose: to expose the scientific community to the cutting edge of forefront research done by leaders in this area from as many as 25 countries and to attract the attention of Mexican researchers to this field of science. These proceedings are intended to be a record of this conference and to serve as a reference for future research which the conference hopes to have initiated. After the pioneering work on controlling chaos of E Ott, C Grebogi and J Yorke appeared in Physical Review Letters in 1990, the number of works on this topic grew tremendously. Our extensive bibliographic search among 110 peer reviewed journals yielded more than 1500 papers on controlling chaos and more than 2500 on synchronization of chaotic systems published during the last decade. The numbers of publications are still at their peaks that began to saturate, in 1998 and 2003, respectively. It is my pleasure to acknowledge the contribution of the program and organizing committees, the funding agencies and cooperating
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Yanting Hu
2013-07-01
Full Text Available Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation. This paper presents a simulation model of a MW-level variable speed wind turbine with a full-scale back-to-back power converter and permanent magnet synchronous generator (PMSG developed in the simulation tool of PSCAD/EMTDC. Flicker emission of this system is investigated. The 3p (three times per revolution power oscillation due to wind shear and tower shadow effects is the significant part in the flicker emission of variable speed wind turbines with PMSG during continuous operation. A new method of flicker mitigation by controlling the rotational speed is proposed. It smoothes the 3p active power oscillations from wind shear and tower shadow effects of the wind turbine by varying the rotational speed of the PMSG. Simulation results show that damping the 3p active power oscillation by using the flicker mitigation speed controller is an effective means for flicker mitigation of variable speed wind turbines with full-scale back-to-back power converters and PMSG during continuous operation.
Study on Chaotic Fault Tolerant Synchronization Control Based on Adaptive Observer
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Dongming Chen
2014-01-01
Full Text Available Aiming at the abrupt faults of the chaotic system, an adaptive observer is proposed to trace the states of the master system. The sufficient conditions for synchronization of such chaotic systems are also derived. Then the feasibility and effectiveness of the proposed method are illustrated via numerical simulations of chaotic Chen system. Finally, the proposed synchronization schemes are applied to secure communication system successfully. The experimental results demonstrate that the employed observer can manage real-time fault diagnosis and parameter identification as well as states tracing of the master system, and so the synchronization of master system and slave system is achieved.
DEFF Research Database (Denmark)
Sharma, Ranjan; Rasmussen, Tonny Wederberg
2008-01-01
This paper includes the experimental and simulated results of variable speed control of a synchronous generator. To achieve controlled variable speed operation, the synchronous generator is loaded with a three phase rectifier and a boost converter. The terminal voltage of the generator can...... be controlled from the converter’s duty cycle if output voltage of the converter is kept constant. This constant voltage is achieved with the help of a grid side inverter. As the speed and the terminal voltage of the generator are directly related to each other, its speed can be controlled for a given torque...... showed some promising results and the overall system response is found positive. Also a Matlab simulation is performed for single turbine system including grid side inverter. The results are presented here in brief....
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Jeong-Min Jo
2017-02-01
Full Text Available In the case of a long-stator linear drive, unlike rotative drives for which speed or position sensors are a single unit attached to the shaft, these sensors extend along the guideway. The position signals transmitted from a maglev vehicle cannot meet the need of the real-time propulsion control in the on-ground inverter power substations. In this paper the design of the propulsion inverter control system with a position estimator for driving a long-stator synchronous motor in a high-speed maglev train is proposed. The experiments have been carried out at the 150 m long guideway at the O-song test track. To investigate the performance of the position estimator, the propulsion control system with, and without, the position estimator are compared. The result confirms that the proposed strategy can meet the dynamic property needs of the propulsion inverter control system for driving long-stator linear synchronous motors.
Maximum Efficiency per Torque Control of Permanent-Magnet Synchronous Machines
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Qingbo Guo
2016-12-01
Full Text Available High-efficiency permanent-magnet synchronous machine (PMSM drive systems need not only optimally designed motors but also efficiency-oriented control strategies. However, the existing control strategies only focus on partial loss optimization. This paper proposes a novel analytic loss model of PMSM in either sine-wave pulse-width modulation (SPWM or space vector pulse width modulation (SVPWM which can take into account both the fundamental loss and harmonic loss. The fundamental loss is divided into fundamental copper loss and fundamental iron loss which is estimated by the average flux density in the stator tooth and yoke. In addition, the harmonic loss is obtained from the Bertotti iron loss formula by the harmonic voltages of the three-phase inverter in either SPWM or SVPWM which are calculated by double Fourier integral analysis. Based on the analytic loss model, this paper proposes a maximum efficiency per torque (MEPT control strategy which can minimize the electromagnetic loss of PMSM in the whole operation range. As the loss model of PMSM is too complicated to obtain the analytical solution of optimal loss, a golden section method is applied to achieve the optimal operation point accurately, which can make PMSM work at maximum efficiency. The optimized results between SPWM and SVPWM show that the MEPT in SVPWM has a better effect on the optimization performance. Both the theory analysis and experiment results show that the MEPT control can significantly improve the efficiency performance of the PMSM in each operation condition with a satisfied dynamic performance.
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Penghan Li
2017-08-01
Full Text Available The increasing penetration of wind power in the grid has driven the integration of wind farms with power systems that are series-compensated to enhance power transfer capability and dynamic stability. This may lead to sub-synchronous control interaction (SSCI problems in series-compensated doubly-fed induction generator (DFIG-based wind farms. To mitigate SSCI, nonlinear controllers based on exact feedback linearization (EFL are proposed in this paper. Before deriving the control laws, the exact feedback linearizability of the studied system is scrutinized. Frequency scanning analysis is employed to test the designed EFL controllers. Moreover, the performance of the EFL controllers is compared to that of classical proportional-integral (PI controllers. A series-compensated 100 MW DFIG-based wind park is utilized to assess the performance of the designed controllers through the alleviation of sub-synchronous resonance. Analyses of the studied system reveal that the resistance is negative under sub-synchronous frequency conditions, whereas the reactance becomes negative at approximately 44 Hz. The designed EFL controllers effectively alleviate SSCI and result in positive reactance and resistance values within the whole sub-synchronous frequency range. The results from the frequency scanning method are also validated through the time domain simulation and the eigenvalue analysis.
Directory of Open Access Journals (Sweden)
Vaidyanathan Sundarapandian
2016-09-01
Full Text Available A hyperjerk system is a dynamical system, which is modelled by an nth order ordinary differential equation with n ≥ 4 describing the time evolution of a single scalar variable. Equivalently, using a chain of integrators, a hyperjerk system can be modelled as a system of n first order ordinary differential equations with n ≥ 4. In this research work, a 4-D novel hyperchaotic hyperjerk system with two nonlinearities has been proposed, and its qualitative properties have been detailed. The novel hyperjerk system has a unique equilibrium at the origin, which is a saddle-focus and unstable. The Lyapunov exponents of the novel hyperjerk system are obtained as L1 = 0.14219, L2 = 0.04605, L3 = 0 and L4 = −1.39267. The Kaplan-Yorke dimension of the novel hyperjerk system is obtained as DKY = 3.1348. Next, an adaptive controller is designed via backstepping control method to stabilize the novel hyperjerk chaotic system with three unknown parameters. Moreover, an adaptive controller is designed via backstepping control method to achieve global synchronization of the identical novel hyperjerk systems with three unknown parameters. MATLAB simulations are shown to illustrate all the main results derived in this research work on a novel hyperjerk system.
DEFF Research Database (Denmark)
Paicu, M. C.; Boldea, I.; Andreescu, G. D.
2009-01-01
This study is focused on very low speed performance comparison between two sensorless control systems based on the novel ‘active flux' concept, that is, the current/voltage vector control versus direct torque and flux control (DTFC) for interior permanent magnet synchronous motor (IPMSM) drives...... with space vector modulation (SVM), without signal injection. The active flux, defined as the flux that multiplies iq current in the dq-model torque expression of all ac machines, is easily obtained from the stator-flux vector and has the rotor position orientation. Therefore notable simplification...
Synchronization and anti-synchronization coexist in Chen-Lee chaotic systems
International Nuclear Information System (INIS)
Chen, J.-H.; Chen, H.-K.; Lin, Y.-K.
2009-01-01
This study demonstrates that synchronization and anti-synchronization can coexist in Chen-Lee chaotic systems by direct linear coupling. Based on Lyapunov's direct method, a linear controller was designed to assure that two different types of synchronization can simultaneously be achieved. Further, the hybrid projective synchronization of Chen-Lee chaotic systems was studied using a nonlinear control scheme. The nonlinear controller was designed according to the Lyapunov stability theory to guarantee the hybrid projective synchronization, including synchronization, anti-synchronization, and projective synchronization. Finally, numerical examples are presented in order to illustrate the proposed synchronization approach.
Directory of Open Access Journals (Sweden)
Chih-Hong Lin
2016-06-01
Full Text Available A permanent magnet (PM synchronous generator system driven by wind turbine (WT, connected with smart grid via AC-DC converter and DC-AC converter, are controlled by the novel recurrent Chebyshev neural network (NN and amended particle swarm optimization (PSO to regulate output power and output voltage in two power converters in this study. Because a PM synchronous generator system driven by WT is an unknown non-linear and time-varying dynamic system, the on-line training novel recurrent Chebyshev NN control system is developed to regulate DC voltage of the AC-DC converter and AC voltage of the DC-AC converter connected with smart grid. Furthermore, the variable learning rate of the novel recurrent Chebyshev NN is regulated according to discrete-type Lyapunov function for improving the control performance and enhancing convergent speed. Finally, some experimental results are shown to verify the effectiveness of the proposed control method for a WT driving a PM synchronous generator system in smart grid.
Synchronization dynamics of two different dynamical systems
International Nuclear Information System (INIS)
Luo, Albert C.J.; Min Fuhong
2011-01-01
Highlights: → Synchronization dynamics of two distinct dynamical systems. → Synchronization, de-synchronization and instantaneous synchronization. → A controlled pendulum synchronizing with the Duffing oscillator. → Synchronization invariant set. → Synchronization parameter map. - Abstract: In this paper, synchronization dynamics of two different dynamical systems is investigated through the theory of discontinuous dynamical systems. The necessary and sufficient conditions for the synchronization, de-synchronization and instantaneous synchronization (penetration or grazing) are presented. Using such a synchronization theory, the synchronization of a controlled pendulum with the Duffing oscillator is systematically discussed as a sampled problem, and the corresponding analytical conditions for the synchronization are presented. The synchronization parameter study is carried out for a better understanding of synchronization characteristics of the controlled pendulum and the Duffing oscillator. Finally, the partial and full synchronizations of the controlled pendulum with periodic and chaotic motions are presented to illustrate the analytical conditions. The synchronization of the Duffing oscillator and pendulum are investigated in order to show the usefulness and efficiency of the methodology in this paper. The synchronization invariant domain is obtained. The technique presented in this paper should have a wide spectrum of applications in engineering. For example, this technique can be applied to the maneuvering target tracking, and the others.
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Limei Zhao
2005-02-01
Full Text Available This paper presents the design and implementation of a DSP-based controller for a super high-speed (>80,000 rpm permanent magnet synchronous motor (PMSM. The PMSM is a key component of the centrifugal compressor drive of a reverse Brayton cryocooler that is currently under development for NASA and Florida Solar Energy Center. The design of the PMSM open-loop control is presented. Experimental results with open-loop control schemes are presented. System optimization and analysis are also illustrated. They verify the effectiveness of the controller design and the optimization scheme.
Hida, Hajime; Tomigashi, Yoshio; Kishimoto, Keiji
High efficiency drive can be achieved by the maximum torque-per-ampere (MTPA) control which used reluctance torque effectively. However, the calculations for estimating rotor position and for controlling the d-axis current are required. The motor parameters of inductance etc. that are easily affected by magnetic saturation are included in those calculations. This paper proposes a new MTPA control method, which is robust against changes of motor parameters caused by magnetic saturation. In addition, complex calculation for d-axis current or reference to the table is not necessary. In this method, we define a novel coordinate frame, which has one axis aligned with the current vector of the MTPA control, and estimate the frame directly. Because the parameter Lqm for estimating the frame is less affected by the magnetic saturation than the conventional Lq, the effect of magnetic saturation on the position estimation can be greatly suppressed. First, an extended electromotive force model based on the proposed frame and a parameter Lqm for an estimation of the frame are derived. Next, the effectiveness of this proposed method is confirmed by simulations and experiments.
International Nuclear Information System (INIS)
Peng Haipeng; Wei Nan; Li Lixiang; Xie Weisheng; Yang Yixian
2010-01-01
In this Letter, time-delay has been introduced in to split the networks, upon which a model of complex dynamical networks with multi-links has been constructed. Moreover, based on Lyapunov stability theory and some hypotheses, we achieve synchronization between two complex networks with different structures by designing effective controllers. The validity of the results was proved through numerical simulations of this Letter.
Synchronized Scheme of Continuous Space-Vector PWM with the Real-Time Control Algorithms
DEFF Research Database (Denmark)
Oleschuk, V.; Blaabjerg, Frede
2004-01-01
synchronous PWM at higher values of the fundamental frequency has also been described. Results of analysis of the spectral characteristics of the output voltage of the inverter show advantage of synchronous PWM in comparison with conventional asynchronous modulation at low indices of the frequency ratio...... their position inside clock-intervals. In order to provide smooth shock-less pulse-ratio changing and quarter-wave symmetry of the voltage waveforms, special synchronising signals are formed on the boundaries of the 60 clock-intervals. The process of gradual transition from continuous to discontinuous...... between the switching and the fundamental frequency. Special attention has been given to the analysis and comparison of the computational effectiveness of the proposed algorithms of synchronized modulation. 0...
International Nuclear Information System (INIS)
Mestha, L.K.; Yeung, K.S.
1991-01-01
One way of synchronizing the SSC Low Energy Booster with the Medium Energy Booster is by matching the longitudinal phase of the designated RF buckets of two machines throughout acceleration to a preprogrammed trajectory. This makes the synchronization predictable in advance. The model associated with the phase-locking is time-varying and model parameters are subjected to disturbance due to errors in the bending magnetic field. Also the disturbance could be due to other feedback loops such as a B-field loop or a beam phase loop in the system. The measured phase error between the two reference waves may not be accurate. Hence in this paper the authors have shown the design of a Sliding-Mode controller for such an application. In the absence of measurement errors and parameter uncertainties and with no disturbance, the controller reduces to a classical gain feedback. Due to the general approach they have adopted in synthesizing the controller, the techniques can be applied to existing synchronization schemes
Online MTPA Control Approach for Synchronous Reluctance Motor Drives Based on Emotional Controller
DEFF Research Database (Denmark)
Daryabeigi, Ehsan; Zarchi, Hossein Abootorabi; Markadeh, G. R. Arab
2015-01-01
is compared with an optimized conventional PI controller under different operating conditions. Simulation and experimental results demonstrate the benefits of the proposed approach. This structure shows superiority of the proposed method, such as fast dynamic, simple implementation and robustness to parameter...... variations and external disturbances in both TCM and SCM. In addition, the proposed MTPA strategy shows a reliable and fast response to operating point change....
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Xiuchun Li
2013-01-01
Full Text Available When the parameters of both drive and response systems are all unknown, an adaptive sliding mode controller, strongly robust to exotic perturbations, is designed for realizing generalized function projective synchronization. Sliding mode surface is given and the controlled system is asymptotically stable on this surface with the passage of time. Based on the adaptation laws and Lyapunov stability theory, an adaptive sliding controller is designed to ensure the occurrence of the sliding motion. Finally, numerical simulations are presented to verify the effectiveness and robustness of the proposed method even when both drive and response systems are perturbed with external disturbances.
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Ufnalski Bartlomiej
2014-12-01
Full Text Available In this paper two different update schemes for the recently developed plug-in direct particle swarm repetitive controller (PDPSRC are investigated and compared. The proposed approach employs the particle swarm optimizer (PSO to solve in on-line mode a dynamic optimization problem (DOP related to the control task in the constant-amplitude constant-frequency voltage-source inverter (CACF VSI with an LC output filter. The effectiveness of synchronous and asynchronous update rules, both commonly used in static optimization problems (SOPs, is assessed and compared in the case of PDPSRC. The performance of the controller, when synthesized using each of the update schemes, is studied numerically.
Fundamental constraints in synchronous muscle limit superfast motor control in vertebrates
DEFF Research Database (Denmark)
Mead, Andrew F; Osinalde, Nerea; Ørtenblad, Niels
2017-01-01
Superfast muscles (SFMs) are extremely fast synchronous muscles capable of contraction rates up to 250 Hz, enabling precise motor execution at the millisecond time scale. SFM phenotypes have been discovered in most major vertebrate lineages, but it remains unknown whether all SFMs share excitation...
A Virtual Inertia Control Strategy for DC Microgrids Analogized with Virtual Synchronous Machines
DEFF Research Database (Denmark)
Wu, Wenhua; Chen, Yandong; Luo, An
2017-01-01
synchronous machine (VSM) is proposed to enhance the inertia of the DC-MG, and to restrain the dc bus voltage fluctuation. The small-signal model of the BGC system is established, and the small-signal transfer function between the dc bus voltage and the dc output current of the BGC is deduced. The dynamic...
Sensorless Speed Control including zero speed of Non Salient PM Synchronous Drives
DEFF Research Database (Denmark)
Rasmussen, Henrik
This paper presents a position sensorless drive of non salient pole PM synchronous motors for all speeds including zero speed. Using adaptive Lyapunov design a new approach for the design of an observer is developed. The resulting scheme leads to a nonlinear full order observer for the motor states...
DEFF Research Database (Denmark)
Kamel, S.; Jurado, F.; Chen, Zhe
2015-01-01
This paper presents an implicit modeling of Static Synchronous Series Compensator (SSSC) in Newton–Raphson load flow method. The algorithm of load flow is based on the revised current injection formulation. The developed model of SSSC is depended on the current injection approach. In this model...
Sensorless control of interior permanent-magnet synchronous motors with compressor load
DEFF Research Database (Denmark)
Huang, Shoudao; Gao, Jian; Xiao, Lei
2013-01-01
This paper analyzes the mathematical model of the interior permanent-magnet synchronous motors (IPMSM). Through the mathematical deformation, the paper proposes the new sensorless method based on sliding mode observer for a IPMSM. The model is only associated with the q-axis inductance, and without...
Sensorless Speed Control including zero speed of Non Salient PM Synchronous Drives
DEFF Research Database (Denmark)
Rasmussen, Henrik
2005-01-01
This paper presents a position sensorless drive of non salient pole PM synchronous motors for all speeds including zero speed. Using adaptive Lyapunov design a new approach for the design of an observer is developed. The resulting scheme leads to a nonlinear full order observer for the motor states...
Sensorless speed Control including Zero Speed on Non Salient PM Synchronous Drives
DEFF Research Database (Denmark)
Rasmussen, Henrik
2006-01-01
This paper presents a position sensorless drive of non salient pole PM synchronous motors for all speeds including zero speed. Using adaptive Lyapunov design a new approach for the design of an observer is developed. The resulting scheme leads to a nonlinear full order observer for the motor states...
DEFF Research Database (Denmark)
Hu, Weihao; Zhang, Yunqian; Chen, Zhe
2013-01-01
Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation. This paper presents a simulation model of a MW-level variable speed wind turbine with a full-scale back-to-back power converter and permanent magnet synchronous generator (PMSG...
International Nuclear Information System (INIS)
Dai, Hao; Si, Gangquan; Jia, Lixin; Zhang, Yanbin
2014-01-01
This paper investigates the problem of finite-time generalized function matrix projective lag synchronization between two different coupled dynamical networks with different dimensions of network nodes. The double power function nonlinear feedback control method is proposed in this paper to guarantee that the state trajectories of the response network converge to the state trajectories of the drive network according to a function matrix in a given finite time. Furthermore, in comparison with the traditional nonlinear feedback control method, the new method improves the synchronization efficiency, and shortens the finite synchronization time. Numerical simulation results are presented to illustrate the effectiveness of this method. (papers)
Transient Control of Synchronous Machine Active and Reactive Power in Micro-grid Power Systems
Weber, Luke G.
power. The scope of this work is to • develop a mathematical model for a salient pole, 2 damper winding synchronous generator with d axis saturation suitable for transient analysis, • develop a mathematical model for a voltage regulator and excitation system using the IEEE AC8B voltage regulator and excitation system template, • develop mathematical models for an energy storage primary control system, LC filter and transformer suitable for transient analysis, • combine the generator and energy storage models in a micro-grid context, • develop mathematical models for electric system components in the stationary abc frame and rotating dq reference frame, • develop a secondary control network for dispatch of micro-grid assets, • establish micro-grid limits of stable operation for step changes in load and power commands based on simulations of model data assuming net load on the micro-grid, and • use generator and electric system models to assess the generator current magnitude during phase-to-ground faults.
Energy Technology Data Exchange (ETDEWEB)
Dechanupaprittha, S.; Watanabe, M.; Mitani, Y. [Kyushu Inst. of Technology, Kitakyushu-shi, Fukuoka (Japan); Hongesombut, K. [Tokyo Electric Power Company, Tokyo (Japan); Ngamroo, I. [King Mongkut' s Inst. of Technhology, Ladkrabang (Thailand)
2007-07-01
Various load demands with abrupt changes adversely affects power system operations and control, which can lead to significant problems such as system frequency oscillations due to insufficient system damping. In interconnected power systems, a local frequency control is needed in a given area. In addition, fluctuations of tie-line power flow should be stabilized. Superconducting magnetic energy storage (SMES) can be used as an effective device to exchange electrical energy with a power system. Wide area monitoring of power systems based on multiple synchronized phasor measurements such as the phasor measurement unit (PMU) using the global positioning system (GPS) offers the possibility of data synchronization at a common time reference. With the GPS, oscillation modes can be detected from measured data by modeling measured data as a coupled vibration model (CVM). This paper presented a practical design of a SMES controller based on wide area synchronized phasor measurement. The CVM can be used to represents an estimated power system model that is used for tuning SMES controller parameters. In addition, it can be used to evaluate the performance and effectiveness of the designed controller in the power system. For the desired damping performance, the controller parameters were optimally tuned using a heuristic optimization method, called a TABU search algorithm. A simulation study was then conducted in order to show and confirm the effectiveness of the design method on a two-area four machine power system. The paper explained the controller design methodology and discussed the application to a two-area, four-machine power system. The simulation revealed that the proposed design method could be implemented in a practical manner. 11 refs., 3 tabs., 7 figs.
DEFF Research Database (Denmark)
Yao, Jun; Zhou, Te; Hu, Weihao
2015-01-01
This article presents an enhanced control strategy for a direct-driven permanent synchronous generator based wind-power generation system with a flywheel energy storage unit. The behaviors of the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit under......, the DC-link voltage oscillations can be effectively suppressed during the unbalanced grid fault by controlling the flywheel energy storage unit. Furthermore, a proportional–integral-resonant controller is designed for the flywheel motor to eliminate the oscillations in the DC-link voltage. Finally......, the proposed coordinated control strategy for the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit has been validated by the simulation results of a 1-MW direct-driven permanent magnet synchronous generator wind power generation system with a flywheel energy...
DEFF Research Database (Denmark)
Ancuti, Mihaela Codruta; Tutelea, Lucian; Andreescu, Gheorghe-Daniel
2014-01-01
This article introduces a control strategy to obtain near-maximum available torque in a wide speed range with sensorless operation via the active flux concept for permanent magnet-reluctance synchronous motor drives. A new torque dq current reference calculator is proposed, with reference torque...... digital simulation results (1–6000 rpm) and experimental results (50–3000 rpm at low inverter available DC voltage of 12 Vdc instead of 48 Vdc) demonstrate the effectiveness of the proposed sensorless control strategy in a wide speed range, with stable and reliable operations up to a speed equal to eight...
Li, Xiao-Jian; Yang, Guang-Hong
2017-03-01
This paper is concerned with the problem of adaptive fault-tolerant synchronization control of a class of complex dynamical networks (CDNs) with actuator faults and unknown coupling weights. The considered input distribution matrix is assumed to be an arbitrary matrix, instead of a unit one. Within this framework, an adaptive fault-tolerant controller is designed to achieve synchronization for the CDN. Moreover, a convex combination technique and an important graph theory result are developed, such that the rigorous convergence analysis of synchronization errors can be conducted. In particular, it is shown that the proposed fault-tolerant synchronization control approach is valid for the CDN with both time-invariant and time-varying coupling weights. Finally, two simulation examples are provided to validate the effectiveness of the theoretical results.
Directory of Open Access Journals (Sweden)
Fezzani Amor
2014-01-01
Full Text Available This paper is devoted to the study of the performances of a robust speed sensorless nonlinear control of permanent magnet synchronous machine. In the first part, the controllers are designed using two methods: the first one using the input output feedback linearization control and the second is a nonlinear control based on Lyapunov theory combined with sliding mode control. This second solution shows good robustness with respect to parameter variations, measurement errors and noises. In the second part, the high order sliding mode speed observer is used to overcome the occurring chattering phenomena. The super twisting algorithm is modified in order to design a speed and position observer for PMSM. Finally, simulation results are given to demonstrate the effectiveness and the good performance of the proposed control methods.
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Kai-Hui Zhao
2017-06-01
Full Text Available To improve the accuracy of torque control for vector control of interior permanent-magnet synchronous machine (IPMSM, this study proposes a torque-sensorless control method based on cascaded sliding mode observer (SMO. First, the active flux model is discussed, which converts the model of IPMSM into the equivalent model of surface-mounted permanent-magnet synchronous machine. Second, to reduce chattering caused by system parameters variations and external disturbances, the cascaded observer is designed, which is composed of a variable gain adaptive SMO and an active flux SMO. The variable gain adaptive SMO is designed to estimate the speed, rotor position and stator resistance in the d–q reference frame. The active flux SMO is designed to estimate the active flux and torque in the α–β reference frame. Global asymptotic stability of the observers is guaranteed by the Lyapunov stability analysis. Finally, simulations and experiments are carried out to verify the effectiveness of the proposed control scheme.
Dharani, S; Rakkiyappan, R; Cao, Jinde; Alsaedi, Ahmed
2017-08-01
This paper explores the problem of synchronization of a class of generalized reaction-diffusion neural networks with mixed time-varying delays. The mixed time-varying delays under consideration comprise of both discrete and distributed delays. Due to the development and merits of digital controllers, sampled-data control is a natural choice to establish synchronization in continuous-time systems. Using a newly introduced integral inequality, less conservative synchronization criteria that assure the global asymptotic synchronization of the considered generalized reaction-diffusion neural network and mixed delays are established in terms of linear matrix inequalities (LMIs). The obtained easy-to-test LMI-based synchronization criteria depends on the delay bounds in addition to the reaction-diffusion terms, which is more practicable. Upon solving these LMIs by using Matlab LMI control toolbox, a desired sampled-data controller gain can be acuqired without any difficulty. Finally, numerical examples are exploited to express the validity of the derived LMI-based synchronization criteria.
Schacht, J.; Laqua, H.; Niedermeyer, H.
2006-08-01
The fusion experiment Wendelstein 7-X demands synchronizing processes in many distributed technical components with an accuracy from milliseconds to nanoseconds. For this purpose a Trigger-Time-Event system (TTE system) was developed. Its main task is the synchronization of all control components and data acquisition systems. It allows time stamping, processing of trigger signals and event messages. The TTE system offers the possibility to program timing sequences and delays, logic combinations or conditions. After a description of the TTE system the task synchronization in the control system of WENDELSTEIN 7-X is discussed. A special software library (TimeLib) allows dealing with time related variables in a simple and comfortable manner. The efficiency of the synchronization system is exemplified
Li, Lan-lan; Hu, Song; Zhao, Li-xin; Ma, Ping
2013-08-01
Lithographic equipments are highly complex machines used to manufacture integrated circuits (ICs). To make larger ICs, a larger lens is required, which, however, is prohibitively expensive. The solution to this problem is to expose a chip not in one flash but in a scanning fashion. For step-and-scan lithographic equipment (wafer scanner), the image quality is decided by many factors, in which synchronization of reticle stage and wafer stage during exposure is a key one. In this paper, the principle of reticle stage and wafer stage was analyzed through investigating the structure of scanners, firstly. While scanning, the reticle stage and wafer stage should scan simultaneously at a high speed and the speed ratio is 1:4. Secondly, an iterative learning controller (ILC) for synchronization of reticle stage and wafer stage is presented. In the controller, a master-slave structure is used, with the wafer stage acting as the master, and the reticle stage as the slave. Since the scanning process of scanner is repetitive, ILC is used to improve tracking performance. A simple design procedure is presented which allows design of the ILC system for the reticle stage and wafer stage independently. Finally, performance of the algorithm is illustrated by simulated on the virtual stages (the reticle stage and wafer stage).The results of simulation experiments and theory analyzing demonstrate that using the proposed controller better synchronization performance can be obtained for the reticle stage and wafer stage in scanner. Theory analysis and experiment shows the method is reasonable and efficient.
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Gao Run-Ze
2017-01-01
Full Text Available The motor drive system represents a key technology for development of the electrical vehicles, and the permanent magnet synchronous motor becomes the mainstream of the new energy vehicle drive motor for the superior performances in power density, low-speed torque density, efficiency and reliability. The paper studies the field weakening control strategy for the interior permanent magnet synchronous motor (IPMSM and provides a field weakening control strategy for the IPMSM at the full-speed range. By studying the mathematical IPMSM model and the methods of conventional vector control and analyzing the operating conditions of the IPMSM at the full-speed range, the paper divides the operating conditions into constant torque operation region I, constant torque operation region II, constant power field weakening operation region and high-speed field weakening operation region to confirm the control strategy algorithm in each region and the transition conditions between regions and provide the current control strategy that the d-axis current and q-axis current are confirmed by the reference torque and the feedback speed. Modeling of the field weakening control strategies in each region is made through the Matlab/Simulink, and simulation of the operating conditions with a steady-state load and a dynamic load is done to verify that the field weakening control strategy in each region is feasible. A co-simulation is made by combining the Matlab/Simulink-based control model, the RecurDyn-based virtual prototype and the RT-LAB to verify the feasible field weakening control strategy.
Hybrid synchronization of hyperchaotic Lu system
Indian Academy of Sciences (India)
In this paper, we study the hybrid synchronization between two identical hyperchaotic Lu systems. Hybrid synchronization of hyperchaotic Lu system is achieved through synchronization of two pairs of states and anti-synchronization of the other two pairs of states. Active controls are designed to achieve hybrid ...
Hybrid synchronization of hyperchaotic Lu system
Indian Academy of Sciences (India)
hyperchaotic Lu systems. Hybrid synchronization of hyperchaotic Lu system is achieved through synchronization of two pairs of states and anti-synchronization of the other two pairs of states. Active controls are designed to achieve hybrid synchronization between drive and response systems using the sum and difference of ...
Zhang, Xiao-Yun; Li, Chuan; Wen, Tian-Fu; Yan, Lu-Nan; Li, Bo; Yang, Jia-Yin; Wang, Wen-Tao; Jiang, Li
2015-01-01
AIM: To investigate whether the use of synchronous hepatectomy and splenectomy (HS) is more effective than hepatectomy alone (HA) for patients with hepatocellular carcinoma (HCC) and hypersplenism. METHODS: From January 2007 to March 2013, 84 consecutive patients with HCC and hypersplenism who underwent synchronous hepatectomy and splenectomy in our center were compared with 84 well-matched patients from a pool of 268 patients who underwent hepatectomy alone. The short-term and long-term outcomes of the two groups were analyzed and compared. RESULTS: The mean time to recurrence was 21.11 ± 12.04 mo in the HS group and 11.23 ± 8.73 mo in the HA group, and these values were significantly different (P = 0.001). The 1-, 3-, 5-, and 7-year disease-free survival rates for the patients in the HS group and the HA group were 86.7%, 70.9%, 52.7%, and 45.9% and 88.1%, 59.4%, 43.3%, and 39.5%, respectively (P = 0.008). Platelet and white blood cell counts in the HS group were significantly increased compared with the HA group one day, one week, one month and one year postoperatively (P Splenectomy and micro-vascular invasion were significant independent prognostic factors for disease-free survival. Gender, tumor number, and recurrence were independent prognostic factors for overall survival. CONCLUSION: Synchronous hepatectomy and hepatectomy potentially improves disease-free survival rates and alleviates hypersplenism without increasing the surgical risks for patients with HCC and hypersplenism. PMID:25741142
Baek, J.; Kwak, S.-S.; Toliyat, H. A.
2015-03-01
This paper proposes a robust and simple direct power control (DPC) of a thyristor-based current-fed drive for generator applications. A current-fed drive and permanent magnet-assisted synchronous reluctance generator (PMa-SynRG) are investigated to deliver 3 kW power using a combustion engine. The current-fed drive utilises a thyristor-based three-phase rectifier to convert generator power to DC-link power and a single-phase current-fed inverter to supply a single-phase inductive load. In addition, a new control algorithm is developed based on DPC for the current-fed drive. The DC-link voltage-based DPC is proposed in order to directly control the output power. The goal of the DPC is to maintain the DC-link voltage at the required output power operating point. The DPC has advantages such as a simple algorithm for constant speed operation. Another feature of the developed current-fed drive is its inherent capability to provide generating action by making the PMa-SynRG operates as a generator, rectifying the phase voltages by means of the three-phase rectifier and feeding the power into the load. These features make the current-fed drive a good candidate for driving any type of synchronous generators including the proposed PMa-SynRG.
International Nuclear Information System (INIS)
Khanzadeh, Alireza; Pourgholi, Mahdi
2016-01-01
A main problem associated with the synchronization of two chaotic systems is that the time in which complete synchronization will occur is not specified. Synchronization time is either infinitely large or is finite but only its upper bound is known and this bound depends on the systems' initial conditions. In this paper we propose a method for synchronizing of two chaotic systems precisely at a time which we want. To this end, time-varying switching surfaces sliding mode control is used and the control law based on Lyapunov stability theorem is derived which is able to synchronize two fractional-order chaotic systems precisely at a pre specified time without concerning about their initial conditions. Moreover, by eliminating the reaching phase in the proposed synchronization scheme, robustness against existence of uncertainties and exogenous disturbances is obtained. Because of the existence of fractional integral of the sign function instead of the sign function in the control equation, the necessity for infinitely fast switching be obviated in this method. To show the effectiveness of the proposed method the illustrative examples under different situations are provided and the simulation results are reported.
Control for stabilizing the alignment position of the rotor of the synchronous motor
Donley, L.I.
1985-03-12
A method and apparatus is described for damping oscillations in the rotor load angle of a synchronous motor to provide stable rotational alignment in high precision applications. The damping method includes sensing the angular position of the rotor and utilizing the position signal to generate an error signal in response to changes in the period of rotation of the rotor. The error signal is coupled to phase shift amplifiers which shift the phase of the motor drive signal in a direction to damp out the oscillations in the rotor load angle.
Energy Technology Data Exchange (ETDEWEB)
Huang, Yunhui; Yuan, Xiaoming; Hu, Jiabing [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Laboratory of Advanced Electromagnetic Engineering and Technology
2012-07-01
In this paper, small-signal stability of DC-link voltage control loop, affected by PLL which is also called synchronization control, is researched under weak grid condition. Similar to small-signal stability analysis of the traditional power system, a small-signal model of the grid-connected converter is presented. This model includes DC-link voltage control loop and PLL. It is analyzed in physics that how synchronization control affects small-signal stability of DC-link voltage control system. Influencing factors of small signal stability of DC-link voltage control system is presented and analyzed including DC-link voltage controller parameter, PLL controller parameter, strength of grid and operating point. An improved control strategy is proposed to enhance the small-signal stability of DC-link voltage control system. Simulations on a 1.5-MW full-capacity wind power generation system are conducted in Matlab/Simulink and the feasibility of the proposed control scheme is validated. (orig.)
Directory of Open Access Journals (Sweden)
Patrick Dallasega
2017-10-01
Full Text Available Sustainability in the supply chain is becoming more and more important for industrial enterprises in different sectors. This research article focuses on construction supply chains (CSCs in the Engineer-to-Order (ETO industry, where every product is almost unique based on specific customer needs and requirements. The development of methods and approaches for more sustainable supply chain management in construction is becoming even more important. Engineering, fabrication of parts and their installation on-site are not always well synchronized in ETO supply chains. The results of such supply chains are long lead times, inefficient material transport and high and uncontrolled levels of work-in-progress (WIP. This article describes a conceptual approach to synchronize demand on-site with supply in manufacturing using the CONstant Work In Progress (ConWIP concept from Lean Management to achieve Just-in-Time (JIT supply. As a result, sustainable supply chains in ETO enterprises, with optimizations from an economic, ecological and social point of view, can be designed. The approach has been validated in an industrial case study.
International Nuclear Information System (INIS)
Gessler, Patrick
2015-11-01
The 3.5 km long European X-Ray Free Electron Laser, currently under construction in northern Germany, will deliver bursts of up to 2700 short X-ray pulses every 100 ms, providing wavelengths between 0.05 and 6 nm, and a repetition rate of 4.5 MHz to several experiment stations. It allows in-depth research in various scientific fields. In order to set-up the beam, position samples and capture the measured variables, information from the accelerator, diagnostic devices and detectors have to be digitized, converted, processed, transferred, concentrated, distributed, reorganized, controlled and saved. All these steps have to be accurately synchronized and sequenced relative to the actual electron bunch or photon pulse in order to guarantee correct data acquisition timings and unique identification of each bunch passing the beamlines. This document provides a complete description of the planning, design, realization and evaluation of the European XFEL Timing System, which implements the synchronization and sequencing of the data acquisition and control electronics for the European X-Ray Free-Electron Laser Facility.
Directory of Open Access Journals (Sweden)
S. Vaidyanathan
2014-11-01
Full Text Available Chaos theory has wide applications and its importance can be seen by the voluminous publications on various applications in several branches of science, commerce and engineering. Control, tracking or regulation and synchronization of different types of chaotic systems are importance areas of research in the control literature and various methods have been adopted over the past few decades for tackling these research problems. Also, the discovery of novel chaotic and hyperchaotic systems in various applications, their qualitative properties and the control of such systems are also important research areas in chaos theory. This paper announces a novel 4-D hyperchaotic Rikitake dynamo system, which is derived by adding a state feedback control to the famous 3-D Rikitake two-disk dynamo system (1958. The frequent and irregular reversals of the Earth’s magnetic field inspired a number of early studies involving electrical currents within the Earth’s molten core. One of the first such models to exhibit reversals was Rikitake’s two-disk dynamo system (Rikitake, 1958. This paper discusses the qualitative properties of the novel hyperchaotic Rikitake dynamo system. We note that the novel hyperchaotic Rikitake dynamo system has no equilibrium points. The Lyapunov exponents of the hyperchaotic Rikitake dynamo system are found as �! = 0.09136, �! = 0.02198, �! = 0 and �! = −2.11190. The Kaplan-Yorke fractional dimension of the novel hyperchaotic Rikitake dynamo system is found as �!" = 3.05367. Next, this paper discusses control and synchronization of the novel hyperchaotic Rikitake dynamo system with unknown parameters using adaptive control method. The main results are established using Lyapunov stability theory and numerically illustrated using MATLAB. Finally, for the 4-D novel hyperchaotic system, an electronic circuit realization in SPICE has been described to confirm the feasibility of the theoretical hyperchaotic Rikitake dynamo
Unidirectional synchronization of Hodgkin-Huxley neurons
International Nuclear Information System (INIS)
Cornejo-Perez, Octavio; Femat, Ricardo
2005-01-01
Synchronization dynamics of two noiseless Hodgkin-Huxley (HH) neurons under the action of feedback control is studied. The spiking patterns of the action potentials evoked by periodic external modulations attain synchronization states under the feedback action. Numerical simulations for the synchronization dynamics of regular-irregular desynchronized spiking sequences are displayed. The results are discussed in context of generalized synchronization. It is also shown that the HH neurons can be synchronized in face of unmeasured states
Unidirectional synchronization of Hodgkin-Huxley neurons
Energy Technology Data Exchange (ETDEWEB)
Cornejo-Perez, Octavio [Division de Matematicas Aplicadas y Sistemas, Computacionales, IPICYT, Apdo. Postal 3-74 Tangamanga, 78231 San Luis Potosi (Mexico)]. E-mail: octavio@ipicyt.edu.mx; Femat, Ricardo [Division de Matematicas Aplicadas y Sistemas, Computacionales, IPICYT, Apdo. Postal 3-74 Tangamanga, 78231 San Luis Potosi (Mexico)]. E-mail: rfemat@ipicyt.edu.mx
2005-07-01
Synchronization dynamics of two noiseless Hodgkin-Huxley (HH) neurons under the action of feedback control is studied. The spiking patterns of the action potentials evoked by periodic external modulations attain synchronization states under the feedback action. Numerical simulations for the synchronization dynamics of regular-irregular desynchronized spiking sequences are displayed. The results are discussed in context of generalized synchronization. It is also shown that the HH neurons can be synchronized in face of unmeasured states.
AutoSync : Automatic duty-cycle control for synchronous low-power listening
DEFF Research Database (Denmark)
Hansen, Morten Tranberg; Kusy, Branislav; Jurdak, Raja
2012-01-01
resources doing idle listening. This problem is particularly exacerbated in multi-radio networks where majority of data comes through the most reliable radio and the duty cycles of other radios could be reduced. We address this issue in AutoSync, a protocol that combines synchronous LPL with automatic...... selection of check intervals to reduce energy consumption in both single and multi-radio networks. We first present the justification for AutoSync's design, and we then discuss our implementation of AutoSync in TinyOS. We compare AutoSync against existing protocols in both simulations and empirical...... experiments. Results show that AutoSync attains a substantial increase in the operational lifetime and mean power consumption over existing protocols in single radio networks and even more in dual radio networks....
International Nuclear Information System (INIS)
Rahbari, Nuh N; Koch, Moritz; Büchler, Markus W; Kieser, Meinhard; Weitz, Jürgen; Lordick, Florian; Fink, Christine; Bork, Ulrich; Stange, Annika; Jäger, Dirk; Luntz, Steffen P; Englert, Stefan; Rossion, Inga
2012-01-01
Currently, it remains unclear, if patients with colon cancer and synchronous unresectable metastases who present without severe symptoms should undergo resection of the primary tumour prior to systemic chemotherapy. Resection of the primary tumour may be associated with significant morbidity and delays the beginning of chemotherapy. However, it may prevent local symptoms and may, moreover, prolong survival as has been demonstrated in patients with metastatic renal cell carcinoma. It is the aim of the present randomised controlled trial to evaluate the efficacy of primary tumour resection prior to systemic chemotherapy to prolong survival in patients with newly diagnosed colon cancer who are not amenable to curative therapy. The SYNCHRONOUS trial is a multicentre, randomised, controlled, superiority trial with a two-group parallel design. Colon cancer patients with synchronous unresectable metastases are eligible for inclusion. Exclusion criteria are primary tumour-related symptoms, inability to tolerate surgery and/or systemic chemotherapy and history of another primary cancer. Resection of the primary tumour as well as systemic chemotherapy is provided according to the standards of the participating institution. The primary endpoint is overall survival that is assessed with a minimum follow-up of 36 months. Furthermore, it is the objective of the trial to assess the safety of both treatment strategies as well as quality of life. The SYNCHRONOUS trial is a multicentre, randomised, controlled trial to assess the efficacy and safety of primary tumour resection before beginning of systemic chemotherapy in patients with metastatic colon cancer not amenable to curative therapy. http://www.controlled-trials.com/ISRCTN30964555
Directory of Open Access Journals (Sweden)
Lisi Tian
2016-12-01
Full Text Available This paper presents a novel position and speed estimation method for low-speed sensorless control of interior permanent-magnet synchronous machines (IPMSMs. The parameter design of the position and speed estimator is based on the sampled current rather than the motor electrical parameters. The proposed method not only simplifies the parameter design, it enables the estimator to work normally even in the condition that the electrical parameters are uncertain or varied. The adaptive filters are adopted to extract the desired high frequency current. The structure and corresponding transfer function are analyzed. To address the shortage of insufficient stop-band attenuation, the structure of the adaptive filter is modified to provide suitable bandwidth and stop-band attenuation simultaneously. The effectiveness of the proposed sensorless control strategy has been verified by simulations and experiments.
Directory of Open Access Journals (Sweden)
Vaidyanathan Sundarapandian
2014-09-01
Full Text Available In this research work, a six-term 3-D novel jerk chaotic system with two hyperbolic sinusoidal nonlinearities has been proposed, and its qualitative properties have been detailed. The Lyapunov exponents of the novel jerk system are obtained as L1 = 0.07765,L2 = 0, and L3 = −0.87912. The Kaplan-Yorke dimension of the novel jerk system is obtained as DKY = 2.08833. Next, an adaptive backstepping controller is designed to stabilize the novel jerk chaotic system with two unknown parameters. Moreover, an adaptive backstepping controller is designed to achieve complete chaos synchronization of the identical novel jerk chaotic systems with two unknown parameters. Finally, an electronic circuit realization of the novel jerk chaotic system using Spice is presented in detail to confirm the feasibility of the theoretical model
Qiao, Wenjun; Tang, Xiaoqi; Zheng, Shiqi; Xie, Yuanlong; Song, Bao
2016-09-01
In this paper, an adaptive two-degree-of-freedom (2Dof) proportional-integral (PI) controller is proposed for the speed control of permanent magnet synchronous motor (PMSM). Firstly, an enhanced just-in-time learning technique consisting of two novel searching engines is presented to identify the model of the speed control system in a real-time manner. Secondly, a general formula is given to predict the future speed reference which is unavailable at the interval of two bus-communication cycles. Thirdly, the fractional order generalized predictive control (FOGPC) is introduced to improve the control performance of the servo drive system. Based on the identified model parameters and predicted speed reference, the optimal control law of FOGPC is derived. Finally, the designed 2Dof PI controller is auto-tuned by matching with the optimal control law. Simulations and real-time experimental results on the servo drive system of PMSM are provided to illustrate the effectiveness of the proposed strategy. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Dan Wang
2016-04-01
Full Text Available In recent years, the increasing penetration level of wind energy into power systems has brought new issues and challenges. One of the main concerns is the issue of dynamic response capability during outer disturbance conditions, especially the fault-tolerance capability during asymmetrical faults. In order to improve the fault-tolerance and dynamic response capability under asymmetrical grid fault conditions, an optimal integrated control scheme for the grid-side voltage-source converter (VSC of direct-driven permanent magnet synchronous generator (PMSG-based wind turbine systems is proposed in this paper. The optimal control strategy includes a main controller and an additional controller. In the main controller, a double-loop controller based on differential flatness-based theory is designed for grid-side VSC. Two parts are involved in the design process of the flatness-based controller: the reference trajectories generation of flatness output and the implementation of the controller. In the additional control aspect, an auxiliary second harmonic compensation control loop based on an improved calculation method for grid-side instantaneous transmission power is designed by the quasi proportional resonant (Quasi-PR control principle, which is able to simultaneously restrain the second harmonic components in active power and reactive power injected into the grid without the respective calculation for current control references. Moreover, to reduce the DC-link overvoltage during grid faults, the mathematical model of DC-link voltage is analyzed and a feedforward modified control factor is added to the traditional DC voltage control loop in grid-side VSC. The effectiveness of the optimal control scheme is verified in PSCAD/EMTDC simulation software.
DEFF Research Database (Denmark)
Agarliţă, Sorin-Cristian; Boldea, I.; Blaabjerg, Frede
2011-01-01
This paper presents a hybrid, motion sensorless control of an Axially Laminated Anisotropic (ALA) Reluctance Synchronous Machine (RSM). The zero and low speed sensorless method is a saliency based High Frequency Signal Injection technique (HFSI) that uses the motor itself as a resolver. The second...... to improve performance at zero and very low speeds. Experimental results validate the proposed control strategies....
DEFF Research Database (Denmark)
Agarlita, Sorin-Cristian; Boldea, Ion; Blaabjerg, Frede
2012-01-01
This paper presents a hybrid, motion sensorless control of an Axially Laminated Anisotropic (ALA) Reluctance Synchronous Machine (RSM). The zero and low speed sensorless method is a saliency based High Frequency Signal Injection technique (HFSI) that uses the motor itself as a resolver. The second...... to improve performance at zero and very low speeds. Experimental results validate the proposed control strategies....
Shinnaka, Shinji
As a simple vector control method for sensorless drives of permanent-magnet synchronous motors, the so-called “Power-Factor-Based (PFB) Vector Control Method” has been proposed. The conventional PFB method directly estimates the phase of the quasi-optimal stator current through a control of the power factor phase, instead of the estimation of the rotor phase. The stator current is controlled in the current reference frame whose secondary axis phase is the same as the stator current phase. This paper proposes a new PEB method where the stator current is controlled in the voltage reference frame whose secondary axis phase is the same as the voltage phase rather than the current phase. It is shown that the similar quasi-optimal stator current control can be attained through the current control with appropriate current commands taking the power factor phase into account. This paper also shows a practical method for generating the current commands and a practical guideline for the design parameters of the new PFB method.
Chaos synchronization between Chen system and Genesio system
International Nuclear Information System (INIS)
Wu Xianyong; Guan Zhihong; Wu Zhengping; Li Tao
2007-01-01
This Letter presents two synchronization schemes between two different chaotic systems. Active control synchronization and adaptive synchronization between Chen system and Genesio system are studied, different controllers are designed to synchronize the drive and response systems, active control synchronization is used when system parameters are known; adaptive synchronization is employed when system parameters are unknown or uncertain. Simulation results show the effectiveness of the proposed schemes
Energy Technology Data Exchange (ETDEWEB)
Perez Guillen, Jesus Artemio
1997-12-31
This thesis presents a computational package for the dynamic analysis of synchronous generators and their controls in a machine - infinite bus system. The package is integrated by a graphic interface for Windows environment and several models for the different components of the generation system. The development of the graphic interface was carried out with object oriented programming under Windows environment, available from Borland C++, which generates a group of menus that integrates an environment of interactive and versatile simulation. The package contains mathematical models of third, fourth, fifth and sixth order for synchronous generators of round and salient poles. Several mathematical models for the excitation systems DC1A, AC1A and ST1A, according to the IEEE classification, are included. Models for thermal and hydraulic turbines with governor of speed are also included, as well as a mathematical model for the power system stabilizer and magnetic saturation on synchronous generators. Numerical methods like Euler, Modified Euler and Runge Kutta of second and fourth order are used to solve the characteristics differential equations of the system under study. Algorithms for graphic generation includes phasor diagram, capability and saturation curves for synchronous machine. Computer models are validated and sensitivity analysis is carried out in order to assess the ef ect of type of model for synchronous machine, excitation systems, power system stabilizer, magnetic saturation in the synchronous generator and different numerical methods of integration. The computational package is useful in teaching and research on the dynamic response of synchronous machines and their controls. [Espanol] En este trabajo se presenta el desarrollo de un paquete computacional para el analisis dinamico de generadores sincronos y sus controles en el esquema de una unidad de generacion - bus infinito. El paquete esta integrado por una interfaz grafica para ambiente Windows y un
Rini Ann Jerin, A; Kaliannan, Palanisamy; Subramaniam, Umashankar
2017-09-01
Fault ride through (FRT) capability in wind turbines to maintain the grid stability during faults has become mandatory with the increasing grid penetration of wind energy. Doubly fed induction generator based wind turbine (DFIG-WT) is the most popularly utilized type of generator but highly susceptible to the voltage disturbances in grid. Dynamic voltage restorer (DVR) based external FRT capability improvement is considered. Since DVR is capable of providing fast voltage sag mitigation during faults and can maintain the nominal operating conditions for DFIG-WT. The effectiveness of the DVR using Synchronous reference frame (SRF) control is investigated for FRT capability in DFIG-WT during both balanced and unbalanced fault conditions. The operation of DVR is confirmed using time-domain simulation in MATLAB/Simulink using 1.5MW DFIG-WT. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
Gu, Jing; Ouyang, Minggao; Li, Jianqiu; Lu, Dongbin; Fang, Chuan; Ma, Yan
2013-01-01
Resolvers are normally employed for rotor positioning in motors for electric vehicles, but resolvers are expensive and vulnerable to vibrations. Hall sensors have the advantages of low cost and high reliability, but the positioning accuracy is low. Motors with Hall sensors are typically controlled by six-step commutation algorithm, which brings high torque ripple. This paper studies the high-performance driving and braking control of the in-wheel permanent magnetic synchronous motor (PMSM) based on low-resolution Hall sensors. Field oriented control (FOC) based on Hall-effect sensors is developed to reduce the torque ripple. The positioning accuracy of the Hall sensors is improved by interpolation between two consecutive Hall signals using the estimated motor speed. The position error from the misalignment of the Hall sensors is compensated by the precise calibration of Hall transition timing. The braking control algorithms based on six-step commutation and FOC are studied. Two variants of the six-step commutation braking control, namely, half-bridge commutation and full-bridge commutation, are discussed and compared, which shows that the full-bridge commutation could better explore the potential of the back electro-motive forces (EMF), thus can deliver higher efficiency and smaller current ripple. The FOC braking is analyzed with the phasor diagrams. At a given motor speed, the motor turns from the regenerative braking mode into the plug braking mode if the braking torque exceeds a certain limit, which is proportional to the motor speed. Tests in the dynamometer show that a smooth control could be realized by FOC driving control and the highest efficiency and the smallest current ripple could be achieved by FOC braking control, compared to six-step commutation braking control. Therefore, FOC braking is selected as the braking control algorithm for electric vehicles. The proposed research ensures a good motor control performance while maintaining low cost and high
Stania, Magdalena; Chmielewska, Daria; Kwaśna, Krystyna; Smykla, Agnieszka; Taradaj, Jakub; Juras, Grzegorz
2015-10-24
More and more frequently stress urinary incontinence affects young healthy women. Hence, early implementation of effective preventive strategies in nulliparous continent women is essential, including pelvic floor muscle training. An initial evaluation based on the bioelectrical activity of the pelvic floor muscles (PFM) during whole-body vibration (WBV) would help to devise the best individualized training for prevention of stress urinary incontinence in woman. We hypothesized that synchronous WBV enhances bioelectrical activity of the PFM which depends on vibration frequency and peak-to-peak vibration displacement. The sample consisted of 36 nulliparous continent women randomly allocated to three comparative groups. Group I and II subjects participated in synchronous whole-body vibrations on a vibration platform; the frequency and peak-to-peak displacement of vibration were set individually for each group. Control participants performed exercises similar to those used in the study groups but without the concurrent application of vibrations. Pelvic floor surface electromyography (sEMG) activity was recorded using a vaginal probe during three experimental trials limited to 30s, 60s and 90 s. The mean amplitude and variability of the signal were normalized to the Maximal Voluntary Contraction - MVC. Friedman's two-way ANOVA revealed a statistically significant difference in the mean normalized amplitudes (%MVC) of the sEMG signal from the PFM during 60s- and 90 s-trials between the group exposed to high-intensity WBV and control participants (p continent women. Prolonged maintenance of a static position significantly decreases the variability of sEMG signal amplitude independent of whole-body vibrations. Single whole-body vibrations in nulliparous continent women does not cause pelvic floor muscle fatigue. The trial was registered in the Australian and New Zealand Clinical Trials Registry (no. ACTRN12615000966594); registration date: 15/09/2015.
Grid Synchronization for Distributed Generations
DEFF Research Database (Denmark)
Peyghami, Saeed; Mokhtari, Hossein; Blaabjerg, Frede
2017-01-01
Distributed generators (DGs) like photovoltaic arrays, wind turbines, and fuel cell modules, as well as distributed storage (DS) units introduce some advantages to the power systems and make it more reliable, flexible, and controllable in comparison with the conventional power systems. Grid...... of interfaces needs to be synchronized with the grid or microgird, and hence, a precise synchronization algorithm—mostly based on phase-locked loop—is required to estimate the phase angle and frequency of the voltage at the coupling point. Unlike synchronous generators, in power electronic interfaced DGs...... grid. Therefore, the synchronization is an important issue in DGs to have a stable and reliable operation....
Energy Technology Data Exchange (ETDEWEB)
Pozniak, K.T.; Romaniuk, R.S.; Jalmuzna, W.; Olowski, K.; Perkuszewski, K.; Zielinski, J. [Warsaw Univ. of Technology (Poland). Inst. of Electronic Systems; Kierzkowski, K. [Warsaw Univ. (Poland). Inst. of Experimental Physics
2005-07-01
It may be predicted now, even assuming very conservative approach, that the next generation of the Low Level RF control systems for future accelerators will use extensively such technologies like: very fast programmable circuits equipped with DSP, embedded PC and optical communication I/O functionalities, as well as multi-gigabit optical transmission of measurement data and control signals. The paper presents the idea and realization of a gigabit synchronous data distributor designed to work in the LLRF control system of TESLA technology based X-ray FEL. The design bases on a relatively simple and cheap FPGA chip Cyclone. Commercially available SERDES (serializer/deserializer) and optical transceiver chips were applied. The optoelectronic module is embedded on the main LLRF BMB (backbone mother board). The MB provides communication with the outside computer control system, programmable chip configuration, integration with other functional modules and power supply. The hardware implementation is here described and the used software for BER (bit-error-rate) testing of the multi-gigabit optical link. The measurement results are presented. The appendix contains a comparison between the available protocols of serial data transmission for FPGA technology. This TESLA Technology Report is a partial contribution to the next version of the SIMCON system which is expected to be released this year. The SIMCON, ver 3. will contain 8 channels and multi-gigabit optical transmission capability. (orig.)
Khan, Mansoor; Yong, Wang; Mustafa, Ehtasham
2017-07-01
After the rapid advancement in the field of power electronics devices and drives for last few decades, there are different kinds of Pulse Width Modulation techniques which have been brought to the market. The applications ranging from industrial appliances to military equipment including the home appliances. The vey common application for the PWM is three phase voltage source inverter, which is used to convert DC to AC in the homes to supply the power to the house in case electricity failure, usually named as Un-interrupted Power Supply. In this paper Space Vector Pulse Width Modulation techniques is discussed and analysed under the control technique named as Field Oriented Control. The working and implementation of this technique has been studied by implementing on the three phase bridge inverter. The technique is used to control the Permanente Magnet Synchronous Motor. The drive system is successfully implemented in MATLAB/Simulink using the mathematical equation and algorithm to achieve the satisfactory results. PI type of controller is used to tuned ers of the motothe parametr i.e. torque and current.
Analysis and controller design for stand-alone VSIs in synchronous reference frame
DEFF Research Database (Denmark)
Ramezani, Malek; Li, Shuhui; Golestan, Saeed
2017-01-01
The common practice for controlling the stand-alone voltage source inverters (VSIs) is to transform abc voltage and current signals to DC signals using the dq transformation, which makes it possible to control the new DC voltage and current signals just using simple proportional-integral controll...
Somov, Sergey
2017-01-01
We consider an information satellite which may be placed on an orbit with altitude from 600 up to 1000 km. We study problems on control of eight electro-reaction engines for a station-keeping of a land-survey satellite on sun-synchronous orbit.
Directory of Open Access Journals (Sweden)
Ramji Tiwari
2017-09-01
Full Text Available In this paper, a novel co-ordinated hybrid maximum power point tracking (MPPT-pitch angle based on a radial basis function network (RBFN is proposed for a variable speed variable pitch wind turbine. The proposed controller is used to maximise output power when the wind speed is low and optimise the power when the wind speed is high. The proposed controller provides robustness to the nonlinear characteristic of wind speed. It uses wind speed, generator speed, and generator power as input variables and utilises the duty cycle and the reference pitch angle as the output control variables. The duty cycle is used to control the converter so as to maximise the power output and the reference pitch angle is used to control the generator speed in order to control the generator output power in the above rated wind speed region. The effectiveness of the proposed controller was verified using MATLAB/Simulink software.
Directory of Open Access Journals (Sweden)
Borzou Yousefi
2017-09-01
Full Text Available Five-phase permanent magnet synchronous motors (PMSM have special applications in which highly accurate speed and torque control of the motor are a strong requirement. Direct Torque Control (DTC is a suitable method for the driver structure of these motors. If in this method, instead of using a common five-phase voltage source inverter, a three-phase to five-phase matrix converter is used, the low-frequency current harmonics and the high torque ripple are limited, and an improved input power factor is obtained. Because the input voltages of such converters are directly supplied by input three-phase supply voltages, an imbalance in the voltages will cause problems such as unbalanced stator currents and electromagnetic torque fluctuations. In this paper, a new method is introduced to remove speed and torque oscillator factors. For this purpose, motor torque equations were developed and the oscillation components created by the unbalanced source voltage, determined. Then, using the active and reactive power reference generator, the controller power reference was adjusted in such a way that the electromagnetic torque of the motor did not change. By this means, a number of features including speed, torque, and flux of the motor were improved in terms of the above-mentioned conditions. Simulations were analyzed using Matlab/Simulink software.
Maaoui-Ben Hassine, Ikram; Naouar, Mohamed Wissem; Mrabet-Bellaaj, Najiba
2016-05-01
In this paper, Model Predictive Control and Dead-beat predictive control strategies are proposed for the control of a PMSG based wind energy system. The proposed MPC considers the model of the converter-based system to forecast the possible future behavior of the controlled variables. It allows selecting the voltage vector to be applied that leads to a minimum error by minimizing a predefined cost function. The main features of the MPC are low current THD and robustness against parameters variations. The Dead-beat predictive control is based on the system model to compute the optimum voltage vector that ensures zero-steady state error. The optimum voltage vector is then applied through Space Vector Modulation (SVM) technique. The main advantages of the Dead-beat predictive control are low current THD and constant switching frequency. The proposed control techniques are presented and detailed for the control of back-to-back converter in a wind turbine system based on PMSG. Simulation results (under Matlab-Simulink software environment tool) and experimental results (under developed prototyping platform) are presented in order to show the performances of the considered control strategies. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.
(statcom) in synchronous compensator
African Journals Online (AJOL)
eobe
for adoption of advanced control technologies such as Flexible Alternating Current Transmission System (FACTS) with fast ... APPLICATION OF STATIC SYNCHRONOUS COMPENSATOR (STATCOM) IN IMPROVING POWER SYSTEM PERFORMANCE, R.A Jokojeje .... supply at bus i and is the reactive power demand at.
Robust control of boost PFC converter using adaptive PLL for line synchronization
DEFF Research Database (Denmark)
Török, Lajos; Mathe, Laszlo; Munk-Nielsen, Stig
2013-01-01
The continuous development of the digital processing technology made advanced control strategies available for switched-mode power-supply applications. This paper presents the study and implementation of an adaptive Phased-Locked Loop (PLL)-based grid-fault tolerant control of a boost PFC converter...
van der Wouden, E.J.; Hermes, D.C.; Gardeniers, Johannes G.E.; van den Berg, Albert
2006-01-01
Electroosmotic flow (EOF) in a microchannel can be controlled by electronic control of the surface charge using an electrode embedded in the wall of the channel. By setting a voltage to the electrode, the zeta-potential at the wall can be changed locally. Thus, the electrode acts as a "gate" for
Fuzzy control techniques applied to a three phase synchronous rectifier current loop
Directory of Open Access Journals (Sweden)
Alberto Berzoy-Lleren
2015-01-01
Full Text Available Este trabajo presenta tres técnicas de control difuso de estructura variable (FVSC aplicadas al lazo de control de corriente en un rectificador síncrono trifásico. Estas técnicas se basan en un controlador PI difuso Takagi-Sugeno (T-S. El primer controlador es un FVSC de primer orden que se usa como referencia. A continuación se presentan y prueban dos estrategias FVSC, FVSC de segundo y tercer orden. Estos esquemas de control se simulan primero y luego se prueban en un rectificador síncrono de propósito general de laboratorio. Los resultados experimentales muestran que el rendimiento del control es bueno en los tres esquemas, logrando compensación de las corrientes armónicas y corrección del factor de potencia.
Directory of Open Access Journals (Sweden)
Suleiman Musa
2017-05-01
Full Text Available Harmonic distortion in power networks has greatly reduced power quality and this affects system stability. In order to mitigate this power quality issue, the shunt active power filter (SAPF has been widely applied and it is proven to be the best solution to current harmonics. This paper evaluates the performance of the modified synchronous reference frame extraction (MSRF algorithm with fuzzy logic controller (FLC based current control pulse width modulation (PWM inverter of three-phase three-wire SAPF to mitigate current harmonics. The proposed FLC is designed with a reduced amount of membership functions (MFs and rules, and thus significantly reduces the computational time and memory size. Modeling and simulations of SAPF are carried out using MATLAB/Simulink R2012a with the power system toolbox under steady-state condition, and this is followed with hardware implementation using a TMS320F28335 digital signal processor (DSP, Specrum Digital Inc., Stafford, TX, USA. The results obtained demonstrate a good and satisfactory response to mitigate the harmonics in the system. The total harmonic distortion (THD for the system has been reduced from 25.60% to 0.92% and 1.41% in the simulation study with and without FLC, respectively. Similarly for the experimental study, the SAPF can compensate for the three-phase load current by reducing THD to 5.07% and 7.4% with and without FLC, respectively.
Directory of Open Access Journals (Sweden)
Dandan Su
2017-12-01
Full Text Available This paper proposes an improved continuous-time model predictive control (CTMPC of permanent magnetic synchronous motors (PMSMs for a wide-speed range, including the constant torque region and the flux-weakening (FW region. In the constant torque region, the mathematic models of PMSMs in dq-axes are decoupled without the limitation of DC-link voltage. However, in the FW region, the mathematic models of PMSMs in dq-axes are cross-coupled together with the limitation of DC-link voltage. A nonlinear PMSMs mathematic model in the FW region is presented based on the voltage angle. The solving of the nonlinear mathematic model of PMSMs in FW region will lead to heavy computation load for digital signal processing (DSP. To overcome such a problem, a linearization method of the voltage angle is also proposed to reduce the computation load. The selection of transiting points between the constant torque region and FW regions is researched to improve the performance of the driven system. Compared with the proportional integral (PI controller, the proposed CTMPC has obvious advantages in dealing with systems’ nonlinear constraints and improving system performance by restraining overshoot current under step torque changing. Both simulation and experimental results confirm the effectiveness of the proposed method in achieving good steady-state performance and smooth switching between the constant torque and FW regions.
DEFF Research Database (Denmark)
Deng, Fujin; Liu, Dong; Chen, Zhe
2017-01-01
This paper investigates a variable speed wind turbine based on permanent magnet synchronous generator and a full-scale power converter in a stand-alone system. An energy storage system(ESS) including battery and fuel cell-electrolyzer combination is connected to the DC link of the full-scale power...... converter through the power electronics interface. Wind is the primary power source of the system, the battery and FC-electrolyzer combination is used as a backup and a long-term storage system to provide or absorb power in the stand-alone system, respectively. In this paper, a control strategy is proposed...... for the operation of this variable speed wind turbine in a stand-alone system, where the generator-side converter and the ESS operate together to meet the demand of the loads. This control strategy is competent for supporting the variation of the loads or wind speed and limiting the DC-link voltage of the full...
Directory of Open Access Journals (Sweden)
Vaidyanathan Sundarapandian
2015-03-01
Full Text Available A hyperjerk system is a dynamical system, which is modelled by an nth order ordinary differential equation with n ⩾ 4 describing the time evolution of a single scalar variable. Equivalently, using a chain of integrators, a hyperjerk system can be modelled as a system of n first order ordinary differential equations with n ⩾ 4. In this research work, a 4-D novel hyperchaotic hyperjerk system has been proposed, and its qualitative properties have been detailed. The Lyapunov exponents of the novel hyperjerk system are obtained as L1 = 0.1448, L2 = 0.0328, L3 = 0 and L4 = −1.1294. The Kaplan-Yorke dimension of the novel hyperjerk system is obtained as DKY= 3.1573. Next, an adaptive backstepping controller is designed to stabilize the novel hyperjerk chaotic system with three unknown parameters. Moreover, an adaptive backstepping controller is designed to achieve global hyperchaos synchronization of the identical novel hyperjerk systems with three unknown parameters. Finally, an electronic circuit realization of the novel jerk chaotic system using SPICE is presented in detail to confirm the feasibility of the theoretical hyperjerk model.
Koehne, Svenja; Behrends, Andrea; Fairhurst, Merle T; Dziobek, Isabel
2016-01-01
Since social cognition is impaired in individuals with autism spectrum disorder (ASD), this study aimed at establishing the efficacy of a newly developed imitation- and synchronization-based dance/movement intervention (SI-DMI) in fostering emotion inference and empathic feelings (emotional reaction to feelings of others) in adults with high-functioning ASD. Fifty-five adults with ASD (IQ ≥85) who were blinded to the aim of the study were assigned to receive either 10 weeks of a dance/movement intervention focusing on interpersonal movement imitation and synchronization (SI-DMI, n = 27) or a control movement intervention (CMI, n = 24) focusing on individual motor coordination (2 participants from each group declined before baseline testing). The primary outcome measure was the objective Multifaceted Empathy Test targeting emotion inference and empathic feelings. Secondary outcomes were scores on the self-rated Interpersonal Reactivity Index. The well-established automatic imitation task and synchronization finger-tapping task were used to quantify effects on imitation and synchronization functions, complemented by the more naturalistic Assessment of Spontaneous Interaction in Movement. Intention-to-treat analyses revealed that from baseline to 3 months, patients treated with SI-DMI showed a significantly larger improvement in emotion inference (d = 0.58), but not empathic feelings, than those treated with CMI (d = -0.04). On the close generalization level, SI-DMI increased synchronization skills and imitation tendencies, as well as whole-body imitation/synchronization and movement reciprocity/dialogue, compared to CMI. SI-DMI can be successful in promoting emotion inference in adults with ASD and warrants further investigation. © 2015 S. Karger AG, Basel.
International Nuclear Information System (INIS)
Aghababa Mohammad Pourmahmood
2012-01-01
The centrifugal flywheel governor (CFG) is a mechanical device that automatically controls the speed of an engine and avoids the damage caused by sudden change of load torque. It has been shown that this system exhibits very rich and complex dynamics such as chaos. This paper investigates the problem of robust finite-time synchronization of non-autonomous chaotic CFGs. The effects of unknown parameters, model uncertainties and external disturbances are fully taken into account. First, it is assumed that the parameters of both master and slave CFGs have the same value and a suitable adaptive finite-time controller is designed. Second, two CFGs are synchronized with the parameters of different values via a robust adaptive finite-time control approach. Finally, some numerical simulations are used to demonstrate the effectiveness and robustness of the proposed finite-time controllers. (general)
Directory of Open Access Journals (Sweden)
Bin Zhao
2014-05-01
Full Text Available This study presents the auxiliary damping control with the reactive power loop on the rotor-side converter of doubly-fed induction generator (DFIG-based wind farms to depress the sub-synchronous resonance oscillations in nearby turbogenerators. These generators are connected to a series capacitive compensation transmission system. First, the damping effect of the reactive power control of the DFIG-based wind farms was theoretically analyzed, and a transfer function between turbogenerator speed and the output reactive power of the wind farms was introduced to derive the analytical expression of the damping coefficient. The phase range to obtain positive damping was determined. Second, the PID phase compensation parameters of the auxiliary damping controller were optimized by a genetic algorithm to obtain the optimum damping in the entire subsynchronous frequency band. Finally, the validity and effectiveness of the proposed auxiliary damping control were demonstrated on a modified version of the IEEE first benchmark model by time domain simulation analysis with the use of DigSILENT/PowerFactory. Theoretical analysis and simulation results show that this derived damping factor expression and the condition of the positive damping can effectively analyze their impact on the system sub-synchronous oscillations, the proposed wind farms reactive power additional damping control strategy can provide the optimal damping effect over the whole sub-synchronous frequency band, and the control effect is better than the active power additional damping control strategy based on the power system stabilizator.
Speed control of synchronous machine by changing duty cycle of DC/DC buck converter
Directory of Open Access Journals (Sweden)
Rashid Al Badwawi
2015-11-01
Full Text Available Renewable energies such as wind or solar energy are naturally intermittent and can create technical challenges to interconnected grid in particular with high integration amounts. In addition, if wind or solar is used to supply power to a stand-alone system, continuous power supply will be met only if sufficient energy storage system is available. The global penetration of renewable energy in power systems is increasing rapidly especially wind and solar photovoltaic (PV systems. Hybrid wind and solar PV generation system becomes very attractive solution in particular for stand-alone applications. It can provide better reliability since the weakness of one system could be complemented by the strength of the other one. When wind energy is integrated into grid, maximum power point tracking control could be used to optimize the output of wind turbine. In variable speed wind turbine, the turbine speed is varied according to the wind speed. This paper presents a comparison between two methods of controlling the speed of a wind turbine in a microgrid namely; Proportional-Integral (PI control of the tip speed ratio and stored power curve. The PI method provides more controllability, but it requires an anemometer to measure the wind speed. The stored power curve method, however, is easier to implement, but the amount of energy extracted can be less. The system has been modelled using Matlab/Simulink.
May, Jeffrey A.; Yeo, Ross K.; Warme, John E.
1984-07-01
Field studies document an apparent eustatic control on facies patterns along a tectonically active margin. In the San Diego Embayment and northern Baja California, progradational-retrogradational shoreline sequences characterize Late Cretaceous and Eocene forearc stratigraphy. Extensive benthonic foraminifera and nannoplankton data provide control on the age and distribution of facies changes along these depositionally compact, bathymetrically steep-gradient margins. The complete stratigraphic package is arranged into three scales and patterns of depositional sequences. Timing and geometry of the two largest sequences provide relative sea-level curves that correlate exceptionally well with worldwide sea-level curves. The major depositional cycle is asymmetric, hundreds of meters thick, characterized by a thin basal retrogradational sequence overlain by a thick progradational sequence; each cycle correlates to a coastal-onlap "supercycle". Smaller scale stratigraphic rhythms, controlled by global "cycles" and "paracycles", compose depositional cycles. Local depostional pulses overprint these two larger order sequences of sedimentation. Coeval cycles and depositional rhythms in isolated coastal basins from Oregon to Baja California further indicate a primary eustatic control on sedimentation. Field-based facies analysis thus supports the use of the "Vail curve" or other coastal-onlap and global sea-level curves as a predictive tool in basin analysis.
Oomen, P. E.; Mulder, J. P. S. H.; Verpoorte, E.; Oleschuk, R. D.
2017-01-01
Droplet manipulation over open surfaces allows one to perform assays with a large degree of control and high throughput, making them appealing for applications in drug screening or (bio)analysis. However, the design, manufacturing and operation of these systems comes with high technical
A dual control mechanism synchronizes riboflavin and sulphur metabolism in Bacillus subtilis
Pedrolli, Danielle Biscaro; Kühm, Christian; Sévin, Daniel C.; Vockenhuber, Michael P.; Sauer, Uwe; Suess, Beatrix; Mack, Matthias
2015-01-01
Flavin mononucleotide (FMN) riboswitches are genetic elements, which in many bacteria control genes responsible for biosynthesis and/or transport of riboflavin (rib genes). Cytoplasmic riboflavin is rapidly and almost completely converted to FMN by flavokinases. When cytoplasmic levels of FMN are sufficient (“high levels”), FMN binding to FMN riboswitches leads to a reduction of rib gene expression. We report here that the protein RibR counteracts the FMN-induced “turn-off” activities of both FMN riboswitches in Bacillus subtilis, allowing rib gene expression even in the presence of high levels of FMN. The reason for this secondary metabolic control by RibR is to couple sulfur metabolism with riboflavin metabolism. PMID:26494285
Czech Academy of Sciences Publication Activity Database
Hengster-Movric, K.; Šebek, M.; Čelikovský, Sergej
2016-01-01
Roč. 353, č. 14 (2016), s. 3457-3486 ISSN 0016-0032 R&D Projects: GA ČR GA13-20433S Grant - others:GA ČR(CZ) GJ16-25493Y Institutional support: RVO:67985556 Keywords : Multi-agent nonlinear systems * structured Lyapunov functions Subject RIV: BC - Control Systems Theory Impact factor: 3.139, year: 2016 http://library.utia.cas.cz/separaty/2016/TR/celikovsky-0462691.pdf
Control Method for Deceleration without Over-Voltage of the Permanent Magnet Synchronous Motor
Notohara, Yasuo; Endo, Tsunehiro
In case of decelerating a permanent magnet motor, an over-voltage occurs on the inverter DC voltage due to the regenerative energy of the motor. In order to reduce the over-voltage, a brake circuit is usually applied to the DC circuit. In this paper a reduction technique of the over-voltage without the brake circuit is described. We proposed the method for controlling the motor d-axis current optimally according to the motor q-axis current to reduce the over-voltage. This method is applied to the salient-pole machine. As a result over-voltage reduction is achieved on a certain condition.
Targeting engineering synchronization in chaotic systems
Bhowmick, Sourav K.; Ghosh, Dibakar
2016-07-01
A method of targeting engineering synchronization states in two identical and mismatch chaotic systems is explained in detail. The method is proposed using linear feedback controller coupling for engineering synchronization such as mixed synchronization, linear and nonlinear generalized synchronization and targeting fixed point. The general form of coupling design to target any desire synchronization state under unidirectional coupling with the help of Lyapunov function stability theory is derived analytically. A scaling factor is introduced in the coupling definition to smooth control without any loss of synchrony. Numerical results are done on two mismatch Lorenz systems and two identical Sprott oscillators.
Adaptive synchronization of chaos in permanent magnet synchronous motors based on passivity theory
International Nuclear Information System (INIS)
Wei Du-Qu; Luo Xiao-Shu; Zhang Bo
2012-01-01
An adaptive synchronization control method is proposed for chaotic permanent magnet synchronous motors based on the property of a passive system. We prove that the controller makes the synchronization error system between the driving and the response systems not only passive but also asymptotically stable. The simulation results show that the proposed method is effective and robust against uncertainties in the systemic parameters. (general)
Ke, Chih-Kun; Lin, Zheng-Hua
2015-09-01
The progress of information and communication technologies (ICT) has promoted the development of healthcare which has enabled the exchange of resources and services between organizations. Organizations want to integrate mobile devices into their hospital information systems (HIS) due to the convenience to employees who are then able to perform specific healthcare processes from any location. The collection and merage of healthcare data from discrete mobile devices are worth exploring possible ways for further use, especially in remote districts without public data network (PDN) to connect the HIS. In this study, we propose an optimal mobile service which automatically synchronizes the telecare file resources among discrete mobile devices. The proposed service enforces some technical methods. The role-based access control model defines the telecare file resources accessing mechanism; the symmetric data encryption method protects telecare file resources transmitted over a mobile peer-to-peer network. The multi-criteria decision analysis method, ELECTRE (Elimination Et Choice Translating Reality), evaluates multiple criteria of the candidates' mobile devices to determine a ranking order. This optimizes the synchronization of telecare file resources among discrete mobile devices. A prototype system is implemented to examine the proposed mobile service. The results of the experiment show that the proposed mobile service can automatically and effectively synchronize telecare file resources among discrete mobile devices. The contribution of this experiment is to provide an optimal mobile service that enhances the security of telecare file resource synchronization and strengthens an organization's mobility.
Energy Technology Data Exchange (ETDEWEB)
Hawes, Martha
2011-02-04
Publications and presentations during the final funding period, including progress in defining the substrate specificity, the primary goal of the project, are listed below. Both short-term and long-term responses mediated by PsUGT1 have been characterized in transgenic or mutant pea, alfalfa, and Arabidopsis with altered expression of PsUGT1. Additional progress includes evaluation of the relationship between control of the cell cycle by PsUGT1 and other glycosyltransferase and glycosidase enzymes that are co-regulated in the legume root cap during the onset of mitosis and differentiation. Transcriptional profiling and multidimensional protein identification technology ('MudPIT') have been used to establish the broader molecular context for the mechanism by which PsUGT1 controls cell cycle in response to environmental signals. A collaborative study with the Norwegian Forest Research Institute (who provided $10,000.00 in supplies and travel funds for collaborator Dr. Toril Eldhuset to travel to Arizona and Dr. H. H. Woo to travel to Norway) made it possible to establish that the inducible root cap system for studying carbohydrate synthesis and solubilization is expressed in gymnosperm as well as angiosperm species. This discovery provides an important tool to amplify the potential applications of the research in defining conserved cell cycle machinery across a very broad range of plant species and habitats. The final work, published during 2009, revealed an additional surprising parallel with mammalian immune responses: The cells whose production is controlled by PsUGT1 appear to function in a manner which is analogous to that of white blood cells, by trapping and killing in an extracellular manner. This may explain why mutation within the coding region of PsUGT1 and its homolog in humans (UGT1) is lethal to plants and animals. The work has been the subject of invited reviews. A postdoctoral fellow, eight undergraduate students, four M.S. students and
High Frequency SSVEP-BCI With Hardware Stimuli Control and Phase-Synchronized Comb Filter.
Chabuda, Anna; Durka, Piotr; Zygierewicz, Jaroslaw
2018-02-01
We present an efficient implementation of brain-computer interface (BCI) based on high-frequency steady state visually evoked potentials (SSVEP). Individual shape of the SSVEP response is extracted by means of a feedforward comb filter, which adds delayed versions of the signal to itself. Rendering of the stimuli is controlled by specialized hardware (BCI Appliance). Out of 15 participants of the study, nine were able to produce stable response in at least eight out of ten frequencies from the 30-39 Hz range. They achieved on average 96±4% accuracy and 47±5 bit/min information transfer rate (ITR) for an optimized simple seven-letter speller, while generic full-alphabet speller allowed in this group for 89±9% accuracy and 36±9 bit/min ITR. These values exceed the performances of high-frequency SSVEP-BCI systems reported to date. Classical approach to SSVEP parameterization by relative spectral power in the frequencies of stimulation, implemented on the same data, resulted in significantly lower performance. This suggests that specific shape of the response is an important feature in classification. Finally, we discuss the differences in SSVEP responses of the participants who were able or unable to use the interface, as well as the statistically significant influence of the layout of the speller on the speed of BCI operation.
Liang, Hongjing; Zhang, Huaguang; Wang, Zhanshan
2015-11-01
This paper considers output synchronization of discrete-time multi-agent systems with directed communication topologies. The directed communication graph contains a spanning tree and the exosystem as its root. Distributed observer-based consensus protocols are proposed, based on the relative outputs of neighboring agents. A multi-step algorithm is presented to construct the observer-based protocols. In light of the discrete-time algebraic Riccati equation and internal model principle, synchronization problem is completed. At last, numerical simulation is provided to verify the effectiveness of the theoretical results. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.
Modified function projective synchronization of chaotic system
International Nuclear Information System (INIS)
Du Hongyue; Zeng Qingshuang; Wang Changhong
2009-01-01
This paper presents a new type synchronization called modified function projective synchronization, where the drive and response systems could be synchronized up to a desired scale function matrix. It is obvious that the unpredictability of the scaling functions can additionally enhance the security of communication. By active control scheme, we take Lorenz system as an example to illustrate above synchronization phenomenon. Furthermore, based on modified function projective synchronization, a scheme for secure communication is investigated in theory. The corresponding numerical simulations are performed to verify and illustrate the analytical results.
Programmable synchronous communications module
International Nuclear Information System (INIS)
Horelick, D.
1979-10-01
The functional characteristics of a programmable, synchronous serial communications CAMAC module with buffering in block format are described. Both bit and byte oriented protocols can be handled in full duplex depending on the program implemented. The main elements of the module are a Signetics 2652 Multi-Protocol Communications Controller, a Zilog Z-808 8 bit microprocessor with PROM and RAM, and FIFOs for buffering
Complete synchronization of two Chen-Lee systems
International Nuclear Information System (INIS)
Sheu, L-J; Chen, J-H; Chen, H-K; Tam, L-M; Lao, S-K; Chen, W-C; Lin, K-T
2008-01-01
This study demonstrates that complete synchronization of two Chen-Lee chaotic systems can be easily achieved. The upper bound of the Chen-Lee chaotic system is estimated numerically. A controller is designed to synchronize two chaotic systems. Sufficient conditions for synchronization are obtained using Lyapunov's direct method. Two numerical examples are presented to verify the proposed synchronization approach
Nonlinear observer based phase synchronization of chaotic systems
International Nuclear Information System (INIS)
Meng Juan; Wang Xingyuan
2007-01-01
This Letter analyzes the phase synchronization problem of autonomous chaotic systems. Based on the nonlinear state observer algorithm and the pole placement technique, a phase synchronization scheme is designed. The phase synchronization of a new chaotic system is achieved by using this observer controller. Numerical simulations further demonstrate the effectiveness of the proposed phase synchronization scheme
Full state hybrid projective synchronization in hyperchaotic systems
International Nuclear Information System (INIS)
Chu Yandong; Chang Yingxiang; Zhang Jiangang; Li Xianfeng; An Xinlei
2009-01-01
In this letter, we investigate the full state hybrid projective synchronization (FSHPS) which includes complete synchronization, anti-synchronization and projective synchronization as its special items. Based on Lyapunov stability theory a controller can be designed for achieving the FSHPS of hyperchaotic systems. Numerical simulations are provided to verify the effectiveness of the proposed scheme.
DEFF Research Database (Denmark)
Blaabjerg, Frede; Teodorescu, Remus; Fatu, M.
2008-01-01
This paper proposes a novel hybrid motion- sensorless control system for permanent magnet synchronous motors (PMSM) using a new robust start-up method called I-f control, and a smooth transition to emf-based vector control. The I-f method is based on separate control of id, iq currents with the r......This paper proposes a novel hybrid motion- sensorless control system for permanent magnet synchronous motors (PMSM) using a new robust start-up method called I-f control, and a smooth transition to emf-based vector control. The I-f method is based on separate control of id, iq currents......-adaptive compensator to eliminate dc-offset and phase-delay. Digital simulations for PMSM start-up with full load torque are presented for different initial rotor-positions. The transitions from I-f to emf motion-sensorless vector control and back as well, at very low-speeds, are fully validated by experimental...
Energy Technology Data Exchange (ETDEWEB)
Eskola, M.
2006-07-01
In this thesis the sensorless control of a permanent magnet synchronous motor (PMSM) is studied. The study has two main purposes. The first is to find a simple and effective method to estimate the rotor position and angular speed of the PMSM. The second is to test the applicability of a matrix converter in sensorless PMSM drives. A matrix converter (MC) enables a direct frequency conversion without DC-link with energy storage. In this thesis two matrix converter topologies, direct and indirect, are studied. The vector modulation and the current commutation strategies of a matrix converter are described. Non-ideal properties of frequency converters such as dead times, overlapping times and voltage losses over semiconductors are disturbances for a control system and position estimator. These non-idealities are studied and the properties of a conventional voltage source inverter are compared to direct and indirect MC topologies. The rotor position and angular speed of the PMSM can be estimated by various methods. Estimators can be divided into model based estimators and signal injection estimators. Model based estimators calculate mechanical quantities using the mathematical representation of the motor. Injection methods usually exploit the saliency of the PMSM. Injected voltage creates currents which are modulated by the rotor position. The position information can be extracted from measured currents. In this thesis the best features of model based and injection estimators are combined. In the proposed hybrid method signal injection is used at low speeds and the transition to model based estimator is performed when the speed increases. The estimator methods used in the hybrid estimator are selected by a comparative analysis and simulations. The most important criteria in the selection of the estimator method in this thesis are: simple algorithm and no need for modification of the modulator software or frequency converter. The suitability of the proposed hybrid
Synchronization of weighted networks and complex synchronized regions
International Nuclear Information System (INIS)
Duan Zhisheng; Chen Guanrong; Huang Lin
2008-01-01
Since the Laplacian matrices of weighted networks usually have complex eigenvalues, the problem of complex synchronized regions should be investigated carefully. The present Letter addresses this important problem by converting it to a matrix stability problem with respect to a complex parameter, which gives rise to several types of complex synchronized regions, including bounded, unbounded, disconnected, and empty regions. Because of the existence of disconnected synchronized regions, the convexity characteristic of stability for matrix pencils is further discussed. Then, some efficient methods for designing local feedback controllers and inner-linking matrices to enlarge the synchronized regions are developed and analyzed. Finally, a weighted network of smooth Chua's circuits is presented as an example for illustration
Tomigashi, Yoshio; Okonogi, Akira; Kishimoto, Keiji
Drum-type washer/dryers are becoming more common in Japan, but the vibration created by unequally distributed clothes is a significant problem in this type of machine. We have developed a vibration control that prevents this imbalance by re-arranging the balancer fluid on the opposite side of the heavier distribution when there is unequal distribution. The drum, which has a large inertia, must be decelerated rapidly to enable the balancer fluid to shift. When a permanent magnetic synchronous motor is decelerated using an inverter, the machine's energy is converted into electrical energy, which regenerates the power supply. A control method has been developed that adjusts the input power of the motor to zero, thereby eliminating the need for a discharge circuit. However, it is not easy to achieve this method with an inexpensive microcomputer. In this paper, a practical braking method in which energy does not regenerate the power supply is examined. First, a simple method in which non-regenerative braking is possible with low input power is proposed, even though the input power is not zero. The effectiveness of this non-regenerative deceleration control is verified by theoretical numerical analysis and by an experiment. The borderline of the voltage vector for the non-generative braking is affected by dead time, and the experimental results differ from the theoretically calculated results. However, it is experimentally confirmed that the proposed non-regenerative deceleration control can be achieved by correcting the impressed voltage vector based on experimental results. Finally, this control is applied to the vibration control of the drum-type washer/dryer, and it is confirmed that the balancer fluid moves as designed.
Stamova, Ivanka; Stamov, Gani
2017-12-01
In this paper, we propose a fractional-order neural network system with time-varying delays and reaction-diffusion terms. We first develop a new Mittag-Leffler synchronization strategy for the controlled nodes via impulsive controllers. Using the fractional Lyapunov method sufficient conditions are given. We also study the global Mittag-Leffler synchronization of two identical fractional impulsive reaction-diffusion neural networks using linear controllers, which was an open problem even for integer-order models. Since the Mittag-Leffler stability notion is a generalization of the exponential stability concept for fractional-order systems, our results extend and improve the exponential impulsive control theory of neural network system with time-varying delays and reaction-diffusion terms to the fractional-order case. The fractional-order derivatives allow us to model the long-term memory in the neural networks, and thus the present research provides with a conceptually straightforward mathematical representation of rather complex processes. Illustrative examples are presented to show the validity of the obtained results. We show that by means of appropriate impulsive controllers we can realize the stability goal and to control the qualitative behavior of the states. An image encryption scheme is extended using fractional derivatives. Copyright © 2017 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Kasinski, K.; Szczygiel, R.; Zabolotny, W.; Lehnert, J.; Schmidt, C.J.; Müller, W.F.J.
2016-01-01
The Silicon Tracking System, Muon Chamber, Transition Radiation Detector and Time-Of-Flight among others are the detector systems of the Compressed Baryonic Matter (CBM) experiment at the FAIR facility. These detector systems will be built with tens of thousands of front-end ASICs exposed to high radiation doses and difficult environmental and interference conditions. A CERN's GBTx-based solution was chosen for combining data from multiple front-end ASICs into an optical link before further concentration and preprocessing in the common Data Processing Board data hub. This paper presents the protocol design addressing the DAQ system requirements, simplifying the ASIC's back-end design and presents its adaptation for the STS and MUCH detector's conditions. A specific link synchronization technique, hit data bandwidth optimization and time synchronization method for the self-triggered front-end chip are presented.
Energy Technology Data Exchange (ETDEWEB)
Kasinski, K., E-mail: kasinski@agh.edu.pl [AGH University of Science and Technology, Department of Measurement and Electronics, Av. Mickiewicza 30, 30-059 Cracow (Poland); Szczygiel, R. [AGH University of Science and Technology, Department of Measurement and Electronics, Av. Mickiewicza 30, 30-059 Cracow (Poland); Zabolotny, W. [Institute of Electronic Systems, Warsaw University of Technology, ul. Nowowiejska 15/19, 00-665 Warsaw (Poland); Lehnert, J.; Schmidt, C.J. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstrasse 1, 64-291 Darmstadt (Germany); Müller, W.F.J. [FAIR Facility for Antiproton and Ion Research in Europe GmbH, Planckstrasse 1, 64-291 Darmstadt (Germany)
2016-11-01
The Silicon Tracking System, Muon Chamber, Transition Radiation Detector and Time-Of-Flight among others are the detector systems of the Compressed Baryonic Matter (CBM) experiment at the FAIR facility. These detector systems will be built with tens of thousands of front-end ASICs exposed to high radiation doses and difficult environmental and interference conditions. A CERN's GBTx-based solution was chosen for combining data from multiple front-end ASICs into an optical link before further concentration and preprocessing in the common Data Processing Board data hub. This paper presents the protocol design addressing the DAQ system requirements, simplifying the ASIC's back-end design and presents its adaptation for the STS and MUCH detector's conditions. A specific link synchronization technique, hit data bandwidth optimization and time synchronization method for the self-triggered front-end chip are presented.
DEFF Research Database (Denmark)
Fernandez, Francisco Daniel Freijedo; Vidal, Ana; Yepes, Alejandro G.
2015-01-01
-space. Subsequently, the characteristic polynomial of the closed-loop system is obtained and a computer-aided parametric analysis is performed to calculate the MIMO root locus as a function of the control gain. By its inspection, it is possible to identify the gain which minimizes the current closed-loop time......Current controller performance is key in gridconnected power converters for renewable energy applications. In this context, a challenging scenario is arising in multi-MW wind turbines, where sampling and switching frequencies tend to be lower and lower as power ratings increase. This strongly...... affects achievable control time constant. With this perspective, this paper presents a systematic procedure for accurate dynamics assessment and tuning of synchronous-frame PI current controllers, which is based on linear control for multiple input multiple output (MIMO) systems. The dominant eigenvalues...
Energy Technology Data Exchange (ETDEWEB)
Araujo, Leandro de Luna; Freire, Selma Cristina de Freitas [Universidade Federal de Campina Grande (COPELE/UFCG), PB (Brazil). Coordenacao de Pos Graduacao em Engenharia Eletrica], Emails: leandrolun@gmail.com, selma.freire@ee.ufcg.edu.br; Guerra, Francisco das Chagas F. [Universidade Federal de Campina Grande (DEE/UFCG), PB (Brazil). Dept. de Engenharia Eletrica], E-mail: chagas@dee.ufcg.edu.br
2009-07-01
This work describes the development of a synchronous key based on micro controller to the switching of three-phase power transformers, which makes possible the achievement of tests to register the inrush current, and the previous establishment of the instantaneous values of the voltage firstly applied to different phases of the energy process. This key is a value tool to the development electric power system projects and to the teaching and researching activities at the laboratory related to transitory phenomena and electric system protection.
International Nuclear Information System (INIS)
Dieperink, J.H.; Finnigan, A.; Kalbreier, W.; Keizer, R.L.; Laffin, M.; Mertens, V.
1989-01-01
Electrostatic separators are used to separate the beams in LEP. The counter-rotating beams are eventually brought into collision in the four low beta insertions, using switches to discharge simultaneously four high voltage (HV) circuits. Each switch consists of four spark gaps mounted in a pressure vessel. A reduction of the gap widths below the self ignition instance by electric motors results in the initiation of the discharges. Synchronization is ensured by the electrical coupling of the electrodes connected to the ground. The design and performance of the computerized precision control of the discharge switch are described. The dynamic characteristics of the prototype switch are also presented. 5 refs., 5 figs
Energy Technology Data Exchange (ETDEWEB)
Benmouyal, Gabriel [Schweitzer Engineering Laboratories, Inc., Longueuil, PQ (Canada); Schweitzer, E.O.; Guzman, A. [Schweitzer Engineering Laboratories Inc., Pullman, WA (United States)
2006-07-15
The easy access to the time synchronization systems, based on satellites and the advance in the computer technologies made possible the sample synchronization of the protection relays in the range of 1 s. Therefore, those relays can provide for synchronized phasorials measurements, eliminating the necessity to have different devices for protection, control and analysis of the electric power system in the applications along the system, and in the traditional protection applications. The applications along the system have different requirements of signal sampling and processing when compared to the traditional protection applications. Those requisites are normally complied by different devices, being um device for each specific function. This paper proposes the combination of the applications mentioned before in a single equipment through a flexible system of signal processing. The addition of phasor synchronized measurements in a protection relay results in the increasing of the power system reliability and provide more simply resources for protection, control and analysis of the perturbation than the supplied by the methods using different information sources.
Impulsive generalized function synchronization of complex dynamical networks
International Nuclear Information System (INIS)
Zhang, Qunjiao; Chen, Juan; Wan, Li
2013-01-01
This Letter investigates generalized function synchronization of continuous and discrete complex networks by impulsive control. By constructing the reasonable corresponding impulsively controlled response networks, some criteria and corollaries are derived for the generalized function synchronization between the impulsively controlled complex networks, continuous and discrete networks are both included. Furthermore, the generalized linear synchronization and nonlinear synchronization are respectively illustrated by several examples. All the numerical simulations demonstrate the correctness of the theoretical results
Energy Technology Data Exchange (ETDEWEB)
Kouadio, L.
1996-12-12
A new method for spark-ignition engine control, more especially in idle conditions, has been developed to prevent engine stalling and improve its idling performances in terms of fuel consumption and pollutant emissions: the car synchronous machine, traditionally operating as an alternator, is used in certain phases to provide an external supplementary torque on the engine shaft. Methods are proposed for optimising the synchronous machine operation as a generator and as an engine, then the main engine control parameters are presented and a linear signal model is established around a nominal idling point, which is used for simulations. Experimental results show evident reductions of fuel consumption and a significant robustness improvement in the engine dynamics
Directory of Open Access Journals (Sweden)
Andrea Bonfiglio
2017-01-01
Full Text Available This paper focuses on the modeling of wind turbines equipped with direct drive permanent magnet synchronous generators for fundamental frequency power system simulations. Specifically, a procedure accounting for the system active power losses to initialize the simulation starting from the load flow results is proposed. Moreover, some analytical assessments are detailed on typical control schemes for fully rated wind turbine generators, thereby highlighting how active power losses play a fundamental role in the effectiveness of the wind generator control algorithm. Finally, the paper proposes analytical criteria to design the structure and the parameters of the regulators of the wind generator control scheme. Simulations performed with Digsilent Power Factory validated the proposed procedure, highlighting the impact of active power losses on the characterization of the initial steady state and that the simplifying assumptions done in order to synthesize the controllers are consistent with the complete modeling performed by the aforementioned power system simulator.
Coupled lasers: phase versus chaos synchronization.
Reidler, I; Nixon, M; Aviad, Y; Guberman, S; Friesem, A A; Rosenbluh, M; Davidson, N; Kanter, I
2013-10-15
The synchronization of chaotic lasers and the optical phase synchronization of light originating in multiple coupled lasers have both been extensively studied. However, the interplay between these two phenomena, especially at the network level, is unexplored. Here, we experimentally compare these phenomena by controlling the heterogeneity of the coupling delay times of two lasers. While chaotic lasers exhibit deterioration in synchronization as the time delay heterogeneity increases, phase synchronization is found to be independent of heterogeneity. The experimental results are found to be in agreement with numerical simulations for semiconductor lasers.
Synchronization in uncertain complex networks.
Chen, Maoyin; Zhou, Donghua
2006-03-01
We consider the problem of synchronization in uncertain generic complex networks. For generic complex networks with unknown dynamics of nodes and unknown coupling functions including uniform and nonuniform inner couplings, some simple linear feedback controllers with updated strengths are designed using the well-known LaSalle invariance principle. The state of an uncertain generic complex network can synchronize an arbitrary assigned state of an isolated node of the network. The famous Lorenz system is stimulated as the nodes of the complex networks with different topologies. We found that the star coupled and scale-free networks with nonuniform inner couplings can be in the state of synchronization if only a fraction of nodes are controlled.
Vestibular hearing and neural synchronization.
Emami, Seyede Faranak; Daneshi, Ahmad
2012-01-01
Objectives. Vestibular hearing as an auditory sensitivity of the saccule in the human ear is revealed by cervical vestibular evoked myogenic potentials (cVEMPs). The range of the vestibular hearing lies in the low frequency. Also, the amplitude of an auditory brainstem response component depends on the amount of synchronized neural activity, and the auditory nerve fibers' responses have the best synchronization with the low frequency. Thus, the aim of this study was to investigate correlation between vestibular hearing using cVEMPs and neural synchronization via slow wave Auditory Brainstem Responses (sABR). Study Design. This case-control survey was consisted of twenty-two dizzy patients, compared to twenty healthy controls. Methods. Intervention comprised of Pure Tone Audiometry (PTA), Impedance acoustic metry (IA), Videonystagmography (VNG), fast wave ABR (fABR), sABR, and cVEMPs. Results. The affected ears of the dizzy patients had the abnormal findings of cVEMPs (insecure vestibular hearing) and the abnormal findings of sABR (decreased neural synchronization). Comparison of the cVEMPs at affected ears versus unaffected ears and the normal persons revealed significant differences (P < 0.05). Conclusion. Safe vestibular hearing was effective in the improvement of the neural synchronization.
Directory of Open Access Journals (Sweden)
Morizane Toshimitsu
2015-12-01
Full Text Available It has been proposed that a novel maglev transport system uses both of the attractive force and thrust force of the Linear Induction Motor (LIM. In our proposal, these two forces will be controlled by two different frequency components. One of the frequency components is synchronous with the motor speed (fm. Another frequency component is drive frequency (fd. Our proposed system enables the independent and simultaneous control of the attractive and thrust force of LIM. Each value of the attractive and the thrust force generated by fm and fd must be identified in order to design that LIM control system. For these purpose, a disc-shaped LIM has been developed as an experimental equipment. The force profiles, especially around zero slip, have been analyzed under experimental conditions.
DEFF Research Database (Denmark)
Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz
2017-01-01
. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method......In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions...... to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method....
DEFF Research Database (Denmark)
Zhao, Bin; Li, Hui; Wang, Mingyu
2014-01-01
and effectiveness of the proposed auxiliary damping control were demonstrated on a modified version of the IEEE first benchmark model by time domain simulation analysis with the use of DigSILENT/PowerFactory. Theoretical analysis and simulation results show that this derived damping factor expression......This study presents the auxiliary damping control with the reactive power loop on the rotor-side converter of doubly-fed induction generator (DFIG)-based wind farms to depress the sub-synchronous resonance oscillations in nearby turbogenerators. These generators are connected to a series capacitive...... compensation transmission system. First, the damping effect of the reactive power control of the DFIG-based wind farms was theoretically analyzed, and a transfer function between turbogenerator speed and the output reactive power of the wind farms was introduced to derive the analytical expression...
Chang, Suchi; Shi, Jindong; Fu, Cuiping; Wu, Xu; Li, Shanqun
2016-01-01
COPD is the third leading cause of death worldwide. Acute exacerbations of COPD may cause respiratory failure, requiring intensive care unit admission and mechanical ventilation. Intensive care unit patients with acute exacerbations of COPD requiring mechanical ventilation have higher mortality rates than other hospitalized patients. Although mechanical ventilation is the most effective intervention for these conditions, invasive ventilation techniques have yielded variable effects. We evaluated pressure-regulated volume control (PRVC) ventilation treatment efficacy and preventive effects on pulmonary barotrauma in elderly COPD patients with respiratory failure. Thirty-nine intubated patients were divided into experimental and control groups and treated with the PRVC and synchronized intermittent mandatory ventilation - volume control methods, respectively. Vital signs, respiratory mechanics, and arterial blood gas analyses were monitored for 2-4 hours and 48 hours. Both groups showed rapidly improved pH, partial pressure of oxygen (PaO2), and PaO2 per fraction of inspired O2 levels and lower partial pressure of carbon dioxide (PaCO2) levels. The pH and PaCO2 levels at 2-4 hours were lower and higher, respectively, in the test group than those in the control group (P0.05). Vital signs during 2-4 hours and 48 hours of treatment showed no statistical difference in either group (P>0.05). The level of peak inspiratory pressure in the experimental group after mechanical ventilation for 2-4 hours and 48 hours was significantly lower than that in the control group (Pvariables were not significantly different between groups (P>0.05). Among elderly COPD patients with respiratory failure, application of PRVC resulted in rapid improvement in arterial blood gas analyses while maintaining a low peak inspiratory pressure. PRVC can reduce pulmonary barotrauma risk, making it a safer protective ventilation mode than synchronized intermittent mandatory ventilation - volume control.
Cluster Synchronization Algorithms
Xia, Weiguo; Cao, Ming
2010-01-01
This paper presents two approaches to achieving cluster synchronization in dynamical multi-agent systems. In contrast to the widely studied synchronization behavior, where all the coupled agents converge to the same value asymptotically, in the cluster synchronization problem studied in this paper,
Anti-synchronization Between Coupled Networks with Two Active Forms
International Nuclear Information System (INIS)
Wu Yongqing; Sun Weigang; Li Shanshan
2011-01-01
This paper studies anti-synchronization and its control between two coupled networks with nonlinear signal's connection and the inter-network actions. If anti-synchronization does not exist between two such networks, adaptive controllers are designed to anti-synchronize them. Different node dynamics and nonidentical topological structures are considered and useful criteria for anti-synchronization between two networks are given. Numerical examples are presented to show the efficiency of our derived results. (general)
Adaptive projective synchronization between different chaotic ...
Indian Academy of Sciences (India)
... with adaptive projective synchronization between two different chaotic systems with parametric uncertainties and external disturbances. Based on Lyapunov stability theory, the projective synchronization between a pair of different chaotic systems with fully unknown parameters are derived. An adaptive control law and a ...
Energy Technology Data Exchange (ETDEWEB)
Bernard, N.
2001-12-15
A new axial field machine with armature and field windings fixed in the air-gap is studied. A double face printed winding is presented and a new tool, using a surface permeance model is developed. A simplified current control is proposed. Finally, considering the association synchronous machine-inverter the loss minimization problem is investigated, including both geometry and command parameters. (author)
Directory of Open Access Journals (Sweden)
S. Vaidyanathan
2014-11-01
Full Text Available This research work describes a nine-term novel 3-D chaotic system with four quadratic nonlinearities and details its qualitative properties. The phase portraits of the 3-D novel chaotic system simulated using MATLAB, depict the strange chaotic attractor of the system. For the parameter values chosen in this work, the Lyapunov exponents of the novel chaotic system are obtained as L1 = 6.8548, L2 = 0 and L3 = −32.8779. Also, the Kaplan-Yorke dimension of the novel chaotic system is obtained as DKY = 2.2085. Next, an adaptive controller is design to achieve global stabilization of the 3-D novel chaotic system with unknown system parameters. Moreover, an adaptive controller is designed to achieve global chaos synchronization of two identical novel chaotic systems with unknown system parameters. Finally, an electronic circuit realization of the novel chaotic system is presented using SPICE to confirm the feasibility of the theoretical model.
Xia, Yonghui; Yang, Zijiang; Han, Maoan
2009-07-01
This paper considers the lag synchronization (LS) issue of unknown coupled chaotic delayed Yang-Yang-type fuzzy neural networks (YYFCNN) with noise perturbation. Separate research work has been published on the stability of fuzzy neural network and LS issue of unknown coupled chaotic neural networks, as well as its application in secure communication. However, there have not been any studies that integrate the two. Motivated by the achievements from both fields, we explored the benefits of integrating fuzzy logic theories into the study of LS problems and applied the findings to secure communication. Based on adaptive feedback control techniques and suitable parameter identification, several sufficient conditions are developed to guarantee the LS of coupled chaotic delayed YYFCNN with or without noise perturbation. The problem studied in this paper is more general in many aspects. Various problems studied extensively in the literature can be treated as special cases of the findings of this paper, such as complete synchronization (CS), effect of fuzzy logic, and noise perturbation. This paper presents an illustrative example and uses simulated results of this example to show the feasibility and effectiveness of the proposed adaptive scheme. This research also demonstrates the effectiveness of application of the proposed adaptive feedback scheme in secure communication by comparing chaotic masking with fuzziness with some previous studies. Chaotic signal with fuzziness is more complex, which makes unmasking more difficult due to the added fuzzy logic.
OVULATORY RESFONSE IN PROGESTERONE SYNCHRONIZED ...
African Journals Online (AJOL)
Conception rate and ovarian function following estrus control by progestetone injections in dairy cattle. J. Anim. Sci. 14, 224. VAN NIEKERK, C.H., BELONJE, P.C. & SPREETH, E.B., 1970. Post partum synchronization of the oestrus period of lactating friesland cows with 6-methyl-17-acetozy-Progesterone. (MAP) and PMSG.
Neural synchronization via potassium signaling
DEFF Research Database (Denmark)
Postnov, Dmitry E; Ryazanova, Ludmila S; Mosekilde, Erik
2006-01-01
Using a relatively simple model we examine how variations of the extracellular potassium concentration can give rise to synchronization of two nearby pacemaker cells. With the volume of the extracellular space and the rate of potassium diffusion as control parameters, the dual nature of this reso...
Neural Synchronization via Potassium Signaling,
DEFF Research Database (Denmark)
Postnov, D. E.; Ryazanova, L. S.; Sosnovtseva, Olga
2006-01-01
Using a relatively simple model we examine how variations of the extracellular potassium concentration can give rise to synchronization of two nearby pacemaker cells. With the volume of the extracellular space and the rate of potassium diffusion as control parameters, the dual nature of this reso...
Synchronization of chaotic systems
International Nuclear Information System (INIS)
Pecora, Louis M.; Carroll, Thomas L.
2015-01-01
We review some of the history and early work in the area of synchronization in chaotic systems. We start with our own discovery of the phenomenon, but go on to establish the historical timeline of this topic back to the earliest known paper. The topic of synchronization of chaotic systems has always been intriguing, since chaotic systems are known to resist synchronization because of their positive Lyapunov exponents. The convergence of the two systems to identical trajectories is a surprise. We show how people originally thought about this process and how the concept of synchronization changed over the years to a more geometric view using synchronization manifolds. We also show that building synchronizing systems leads naturally to engineering more complex systems whose constituents are chaotic, but which can be tuned to output various chaotic signals. We finally end up at a topic that is still in very active exploration today and that is synchronization of dynamical systems in networks of oscillators
Energy Technology Data Exchange (ETDEWEB)
Martinez Alvarado, Raziel
2002-11-01
This thesis shows the design and implementation of a speed-power fuzzy-logic controller. The controller implementation was carried out on the Schrage motor-synchronous generator set. The synchronous alternator is rated 7 kVA, 220 V, 1800 rpm, 60 Hz. Two PI like fuzzy-logic controllers were developed with 9 and 25 rules. The controllers use the speed or power error and its integral as input variables and as an output the control signal from the brush-positioner of the Schrage motor. At the controller design stage, the anfis (adaptive-network-based fuzzy inference system) learning and structure procedure was used for tuning up parameters of the membership functions used on the designed fuzzy controllers. These controllers are first-order Sugeno-type. The designed controllers were tested on the motor-generator set under loaded and no-loaded conditions. It was found that PI-9 rules fuzzy-logic controller had better performance on both operating conditions. [Spanish] En este trabajo de tesis se presenta el diseno e implementacion de un controlador difuso de velocidad-potencia, para un grupo motor Schrage-generador sincrono de 7 kVA, 220 V, 1800 rpm, 60 Hz. Se implementaron controladores difusos del tipo PI de 9 y 25 reglas. Estos controladores utilizan como variables de entrada el error y la integral del error, de velocidad o potencia segun corresponda, y como variable de salida la senal de control del posicionador de las escobillas del motor Schrage. En la etapa de diseno de los controladores, se utilizo la estructura y el procedimiento de aprendizaje anfis (Sistema de Inferencia Difuso Basado en Redes Adaptables, por sus siglas en ingles) para sintonizar los parametros de las funciones de membresia de los controladores difusos, los cuales son del tipo Sugeno de primer orden. Con la finalidad de validar los controladores disenados, se realizaron pruebas experimentales al grupo motor-generador en condiciones de vacio y carga. Se encontro que el controlador difuso tipo
Effects of frustration on explosive synchronization
Huang, Xia; Gao, Jian; Sun, Yu-Ting; Zheng, Zhi-Gang; Xu, Can
2016-12-01
In this study, we consider the emergence of explosive synchronization in scale-free networks by considering the Kuramoto model of coupled phase oscillators. The natural frequencies of oscillators are assumed to be correlated with their degrees and frustration is included in the system. This assumption can enhance or delay the explosive transition to synchronization. Interestingly, a de-synchronization phenomenon occurs and the type of phase transition is also changed. Furthermore, we provide an analytical treatment based on a star graph, which resembles that obtained in scale-free networks. Finally, a self-consistent approach is implemented to study the de-synchronization regime. Our findings have important implications for controlling synchronization in complex networks because frustration is a controllable parameter in experiments and a discontinuous abrupt phase transition is always dangerous in engineering in the real world.
Directory of Open Access Journals (Sweden)
Ester Hamatwi
2017-01-01
Full Text Available Due to the intermittent nature of wind, the wind power output tends to be inconsistent, and hence maximum power point tracking (MPPT is usually employed to optimize the power extracted from the wind resource at a wide range of wind speeds. This paper deals with the rotor speed control of a 2 MW direct-driven permanent magnet synchronous generator (PMSG to achieve MPPT. The proportional-integral (PI, proportional-derivative (PD, and proportional-integral-derivative (PID controllers have widely been employed in MPPT studies owing to their simple structure and simple design procedure. However, there are a number of shortcomings associated with these controllers; the trial-and-error design procedure used to determine the P, I, and D gains presents a possibility for poorly tuned controller gains, which reduces the accuracy and the dynamic performance of the entire control system. Moreover, these controllers’ linear nature, constricted operating range, and their sensitivity to changes in machine parameters make them ineffective when applied to nonlinear and uncertain systems. On the other hand, phase-lag compensators are associated with a design procedure that is well defined from fundamental principles as opposed to the aforementioned trial-and-error design procedure. This makes the latter controller type more accurate, although it is not well developed yet, and hence it is the focus of this paper. The simulation results demonstrated the effectiveness of the proposed MPPT controller.
Analysis of Synchronization for Coupled Hybrid Systems
DEFF Research Database (Denmark)
Li, Zheng; Wisniewski, Rafal
2006-01-01
subsystem will cause low efficiency, inferior control performance and a high wear on the compressor. This paper takes the supermarket refrigeration systems as an example to analyze the synchronization and its coupling strengths of coupled hybrid systems, which may provide a base for further research...... of control strategies. This paper combines topology and section mapping theories together to show a new way of analyzing hybrid systems......In the control systems with coupled multi-subsystem, the subsystems might be synchronized (i.e. all the subsystems have the same operation states), which results in negative influence to the whole system. For example, in the supermarket refrigeration systems, the synchronized switch of each...
Fuzzy stability and synchronization of hyperchaos systems
International Nuclear Information System (INIS)
Wang Junwei; Xiong Xiaohua; Zhao Meichun; Zhang Yanbin
2008-01-01
This paper studies stability and synchronization of hyperchaos systems via a fuzzy-model-based control design methodology. First, we utilize a Takagi-Sugeno fuzzy model to represent a hyperchaos system. Second, we design fuzzy-model-based controllers for stability and synchronization of the system, based on so-called 'parallel distributed compensation (PDC)'. Third, we reduce a question of stabilizing and synchronizing hyperchaos systems to linear matrix inequalities (LMI) so that convex programming techniques can solve these LMIs efficiently. Finally, the generalized Lorenz hyperchaos system is employed to illustrate the effectiveness of our designing controller
Adaptive projective synchronization of different chaotic systems with nonlinearity inputs
International Nuclear Information System (INIS)
Niu Yu-Jun; Pei Bing-Nan; Wang Xing-Yuan
2012-01-01
We investigate the projective synchronization of different chaotic systems with nonlinearity inputs. Based on the adaptive technique, sliding mode control method and pole assignment technique, a novel adaptive projective synchronization scheme is proposed to ensure the drive system and the response system with nonlinearity inputs can be rapidly synchronized up to the given scaling factor. (general)
Directory of Open Access Journals (Sweden)
Hongjuan Liu
2014-01-01
Full Text Available A new general and systematic coupling scheme is developed to achieve the modified projective synchronization (MPS of different fractional-order systems under parameter mismatch via the Open-Plus-Closed-Loop (OPCL control. Based on the stability theorem of linear fractional-order systems, some sufficient conditions for MPS are proposed. Two groups of numerical simulations on the incommensurate fraction-order system and commensurate fraction-order system are presented to justify the theoretical analysis. Due to the unpredictability of the scale factors and the use of fractional-order systems, the chaotic data from the MPS is selected to encrypt a plain image to obtain higher security. Simulation results show that our method is efficient with a large key space, high sensitivity to encryption keys, resistance to attack of differential attacks, and statistical analysis.
International Nuclear Information System (INIS)
Kajii, Shin-ichirou; Yasuda, Chiaki; Yamashita, Toshio; Abe, Hiroshi; Kanki, Hiroshi
2004-01-01
In the seismic design of nuclear power plant, it is recently considered to use probability method in a addition to certainty method. The former method is called Seismic Probability Safety Assessment (Seismic PSA). In case of seismic PSA for some components of a nuclear power plant using a shaking table, it is necessary for some limited conditions with high level of accelerations such as actual conditions. However, it might be difficult to achieve the test conditions that a current shaking table based on hydraulic power system is intended for the test facility. Therefore, we have been planning out a test method in which both a current and another shaking table called a booster device are applied. This paper describes the verification test of a synchronized control between a current shaking table and a booster device. (author)
Chaos synchronization of a unified chaotic system via partial linearization
International Nuclear Information System (INIS)
Yu Yongguang; Li Hanxiong; Duan Jian
2009-01-01
A partial linearization method is proposed for realizing the chaos synchronization of an unified chaotic system. Through synchronizing partial state of the chaotic systems can result in the synchronization of their entire states, and the resulting controller is singularity free. The results can be easily extended to the synchronization of other similar chaotic systems. Simulation results are conducted to show the effectiveness of the method.
An approach of parameter estimation for non-synchronous systems
International Nuclear Information System (INIS)
Xu Daolin; Lu Fangfang
2005-01-01
Synchronization-based parameter estimation is simple and effective but only available to synchronous systems. To come over this limitation, we propose a technique that the parameters of an unknown physical process (possibly a non-synchronous system) can be identified from a time series via a minimization procedure based on a synchronization control. The feasibility of this approach is illustrated in several chaotic systems
Clements, Mark A; Staggs, Vincent S
2017-05-01
Many individuals with type 1 diabetes (T1D) upload and review blood glucose data between clinic visits. Mobile phone applications that receive data from a "connected" glucometer and that support pattern management are available and have the capacity to make data upload and review less burdensome. Whether mobile apps can improve diabetes self-management among individuals with type 1 diabetes remains unknown. We analyzed retrospective data on 81 youths with T1D who were trained to use a glucometer-connected mobile app in their self-management. To assess the effect of glucometer synchronization ("sync") rate on hemoglobin A1c (HbA1c), mean blood glucose (mBG), and daily frequency of SMBG, we regressed those clinical outcomes on the frequency of glucometer syncs with the mobile app after controlling for other clinical care variables. Median age was 14.0 (IQR 10.4-15.9) years, median duration of diabetes was 4.9 (2.7, 7.5) years, and median baseline HbA1c was 8.6% (7.9, 9.8). The sample was 49% male and 86% white. Youths with T1D synchronized glucometer data with the mobile app an average of 0.22 times per week (range 0-2.25). The glucometer sync rate did not have a statistically significant association with HbA1c or mean BG; in contrast, data sync frequency was associated with the frequency of self-monitoring of blood glucose (SMBG) such that each additional sync was associated with a 2.3-fold increase in SMBG frequency ( P mobile app may increase an individual's engagement with other aspects of care (eg, SMBG frequency). Whether diabetes device-connected mobile apps can improve glycemic control remains to be determined.
Generalized projective synchronization of chaotic nonlinear gyros coupled with dead-zone input
International Nuclear Information System (INIS)
Hung, M.-L.; Yan, J.-J.; Liao, T.-L.
2008-01-01
This paper addresses the synchronization problem of drive-response chaotic gyros coupled with dead-zone nonlinear input. Using the sliding mode control technique, a novel control law is established which guarantees generalized projective synchronization even when the dead-zone nonlinearity is present. Numerical simulations are presented to verify that the synchronization can be achieved by using the proposed synchronization scheme
Kim, Chang Woo; Baek, Jeong-Heum; Choi, Gyu-Seog; Yu, Chang Sik; Kang, Sung Bum; Park, Won Cheol; Lee, Bong Hwa; Kim, Hyeong Rok; Oh, Jae Hwan; Kim, Jae-Hwang; Jeong, Seung-Yong; Ahn, Jung Bae; Baik, Seung Hyuk
2016-01-19
Approximately 20 % of all patients with colorectal cancer are diagnosed as having Stage IV cancer; 80 % of these present with unresectable metastatic lesions. It is controversial whether chemotherapy with or without primary tumor resection (PTR) is effective for the treatment of patients with colorectal cancer with unresectable metastasis. Primary tumor resection could prevent tumor-related complications such as intestinal obstruction, perforation, bleeding, or fistula. Moreover, it may be associated with an increase in overall survival. However, surgery delays the use of systemic chemotherapy and affects the systemic spread of malignancy. Patients with colon and upper rectal cancer patients with asymptomatic, synchronous, unresectable metastasis will be included after screening. They will be randomized and assigned to receive chemotherapy with or without PTR. The primary endpoint measure is 2-year overall survival rate and the secondary endpoint measures are primary tumor-related complications, quality of life, surgery-related morbidity and mortality, interventions with curative intent, chemotherapy-related toxicity, and total cost until death or study closing day. The authors hypothesize that the group receiving PTR following chemotherapy would show a 10 % improvement in 2-year overall survival, compared with the group receiving chemotherapy alone. The accrual period is 3 years and the follow-up period is 2 years. Based on the inequality design, a two-sided log-rank test with α-error of 0.05 and a power of 80 % was conducted. Allowing for a drop-out rate of 10 %, 480 patients (240 per group) will need to be recruited. Patients will be followed up at every 3 months for 3 years and then every 6 months for 2 years after the last patient has been randomized. This randomized controlled trial aims to investigate whether PTR with chemotherapy shows better overall survival than chemotherapy alone for patients with asymptomatic, synchronous unresectable
Energy Technology Data Exchange (ETDEWEB)
Amara, Y.
2001-12-01
Double excitation machines are synchronous machines where two excitation circuits coexist: one with permanent magnets and the other with windings. This study shows that double excitation allows to combine the advantages of synchronous machines with winded inductor with those of permanent magnet machines. This concept allows a better dimensioning of the converter-machine set and a better energy management. In order to allow the operation of permanent magnet machines over a wide range of speeds, it is necessary to have a magnetic reaction of the induced circuit of the same order than the excitation flux. On the other hand, the power factor is weaker and the power supply converter is over-dimensioned. The double excitation allows the permanent magnet machines to work over a large speed range with a better power factor, even when the magnetic reaction of the induced circuit is relatively weak with respect to the excitation flux. (J.S.)
The complete, lag and anticipated synchronization of a BLDCM chaotic system
International Nuclear Information System (INIS)
Ge Zhengming; Lin Guohua
2007-01-01
The complete, lag and anticipated synchronizations of two identical autonomous chaotic systems, Brushless DC Motors (BLDCM) systems, are studied in this paper. PC method, linear coupling and active control are used for the achievements of the complete and the lag synchronizations. Linear coupling method and active control is used for the anticipated synchronization. Generalized lag, anticipated and complete synchronization are obtained by active control. Finally, the generalized lag synchronization of BLDCM system and Lorenz system is studied
A note on synchronization between two different chaotic systems
International Nuclear Information System (INIS)
Park, Ju H.
2009-01-01
In this paper, a new control method based on the Lyapunov method and linear matrix inequality framework is proposed to design a stabilizing controller for synchronizing two different chaotic systems. The feedback controller is consisted of two parts: linear dynamic control law and nonlinear control one. By this control law, the exponential stability for synchronization between two different chaotic systems is guaranteed. As applications of proposed method, synchronization problem between Genesio-Tesi system and Chen system has been investigated, and then the similar approach is applied to the synchronization problem between Roessler system and Lorenz system.
Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M.
2017-01-01
In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method. PMID:28192436
Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M
2017-01-01
In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method.
Mousa, Mohamed G; Allam, S M; Rashad, Essam M
2018-01-01
This paper proposes an advanced strategy to synchronize the wind-driven Brushless Doubly-Fed Reluctance Generator (BDFRG) to the grid-side terminals. The proposed strategy depends mainly upon determining the electrical angle of the grid voltage, θ v and using the same transformation matrix of both the power winding and grid sides to ensure that the generated power-winding voltage has the same phase-sequence of the grid-side voltage. On the other hand, the paper proposes a vector-control (power-winding flux orientation) technique for maximum wind-power extraction under two schemes summarized as; unity power-factor operation and minimum converter-current. Moreover, a soft-starting method is suggested to avoid the employed converter over-current. The first control scheme is achieved by adjusting the command power-winding reactive power at zero for a unity power-factor operation. However, the second scheme depends on setting the command d-axis control-winding current at zero to maximize the ratio of the generator electromagnetic-torque per the converter current. This enables the system to get a certain command torque under minimum converter current. A sample of the obtained simulation and experimental results is presented to check the effectiveness of the proposed control strategies. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
Tomigashi, Yoshio; Ueyama, Kenji
A method for directly estimating the axis corresponding to the current phase in maximum torque per ampere (MTPA) control is proposed for sensorless vector control. This axis is called the maximum torque control (MTC) axis. In past studies concerning such methods, the behavior of the axis has been considered only for the case of MTPA control and not for an arbitrary current vector (with flux weakening control) that has a phase different from that for MTPA control. This paper enhances the definition of the MTC axis for an arbitrary current vector, describes an extended EMF model based on the MTC axis, and presents a method that can directly estimate the axis for an arbitrary current vector with flux weakening control. The effectiveness of the proposed method is confirmed by numerical analysis results.
Al-Wais, Saba; Khoo, Suiyang; Lee, Tae Hee; Shanmugam, Lakshmanan; Nahavandi, Saeid
2018-01-01
This paper is devoted to the synchronization problem of tele-operation systems with time-varying delay, disturbances, and uncertainty. Delay-dependent sufficient conditions for the existence of integral sliding surfaces are given in the form of Linear Matrix Inequalities (LMIs). This guarantees the global stability of the tele-operation system with known upper bounds of the time-varying delays. Unlike previous work, in this paper, the controller gains are designed but not chosen, which increases the degree of freedom of the design. Moreover, Wirtinger based integral inequality and reciprocally convex combination techniques used in the constructed Lypunove-Krasoviskii Functional (LKF) are deemed to give less conservative stability condition for the system. Furthermore, to relax the analysis from any assumptions regarding the dynamics of the environment and human operator forces, H ∞ design method is used to involve the dynamics of these forces and ensure the stability of the system against these admissible forces in the H ∞ sense. This design scheme combines the strong robustness of the sliding mode control with the H ∞ design method for tele-operation systems which is coupled using state feedback controllers and inherit variable time-delays in their communication channels. Simulation examples are given to show the effectiveness of the proposed method. Copyright © 2017 ISA. All rights reserved.
Helbling, Ignacio M; Busatto, Carlos A; Fioramonti, Silvana A; Pesoa, Juan I; Santiago, Liliana; Estenoz, Diana A; Luna, Julio A
2018-02-20
Planned reproduction in cattle involves regulation of estrous cycle and the use of artificial insemination. Cycle control includes the administration of exogenous progesterone during 5-8 days in a controlled manner allowing females to synchronize their ovulation. Several progesterone delivery systems are commercially available but they have several drawbacks. The aim of the present contribution was to evaluate chitosan microparticles entrapping progesterone as an alternative system. Microparticles were prepared by spray drying. The effect of formulation parameters and experimental conditions on particle features and delivery was studied. A mathematical model to predict progesterone plasma concentration in animals was developed and validated with experimental data. Microparticle size was not affected by formulation parameters but sphericity enhances as Tween 80 content increases and it impairs as TPP content rises. Z potential decreases as phosphate content rises. Particles remain stable in acidic solution but the addition of surfactant is required to stabilize dispersions in neutral medium. Encapsulation efficiencies was 69-75%. In vitro delivery studies showed burst and diffusion-controlled phases, being progesterone released faster at low pH. In addition, delivery extend in cows was affected mainly by particle size and hormone initial content, while the amount injected altered plasma concentration. Theoretical predictions with excellent accuracy were obtained. The mathematical model developed can help to find proper particle features to reach specific delivery rates in the animals. This not only save time, money and effort but also minimized experimentation with animals which is desired from an ethical point of view.
Directory of Open Access Journals (Sweden)
Md Ruhul Amin
2017-12-01
Full Text Available In this paper, a fast self-synchronization known as virtual synchronous converter (VSCon between single-phase microgrid and inverter in low-voltage microgrid, has been developed in Matlab/Simulink. The idea is to any phase locked loop (PLL circuit for inverter-microgrid synchronization in order to improve the synchronization time. As known, it is difficult and lengthy process to tune the PLL gain parameters to reach suitable performance for synchronizing among the voltage, phase-angle and frequency between them. Due to this problem, a fast self synchronization technique is needed in order to minimize the time losses at the microgrid connection. Therefore, the VSCon has been developed which is based on the synchronous generator mathematical model but in virtual environment representation. It has been applied in the inverter control for generating switching pattern to the inverter switches in order to respond to the grid voltage for improve the synchronization. For a prove of concept, several simulation tests in MATLAB models have been conducted, in order to see the effectiveness of this VSCon. First test has been conducted, when a 240V, 50Hz frequency grid source is used for observing the self-synchronization the system with the power flows output. Furthermore, the next test is conducted when the grid frequency is changed from the rated frequency at 50Hz to 51Hz and the result shows the VSCon in inverter control takes nearly 40ms to synchronize to this new frequency value. The test on grid phase-angle delay also been tested when ac grid voltage has 150 phase delay. As from all the results, the improved inverter control with VSCon structure is able to have fast and self-synchronized between the invertergrid connection before the power from the inverter can be transferred.
Merry, Philip
2017-01-01
LAY SUMMARY SYNCHRONICITY AND LEADERSHIP TILBURG PHD DISSERTATION, PHILIP MERRY World’s First PhD to Research Synchronicity And Leadership Using Grounded Theory OUT OF THE BLUE COINCIDENCES: research topic Most people have had the experience of thinking of someone and then, almost magically have
Indian Academy of Sciences (India)
For networks with time-varying topology we compare the synchronization properties of these networks with the corresponding time-average network. We find that if the different coupling matrices corresponding to the time-varying networks commute with each other then the stability of the synchronized state for both the ...
Bistability in Coupled Oscillators Exhibiting Synchronized Dynamics
Olusola, O. I.; Vincent, U. E.; Njah, A. N.; Olowofela, J. A.
2010-05-01
We report some new results associated with the synchronization behavior of two coupled double-well Duffing oscillators (DDOs). Some sufficient algebraic criteria for global chaos synchronization of the drive and response DDOs via linear state error feedback control are obtained by means of Lyapunov stability theory. The synchronization is achieved through a bistable state in which a periodic attractor co-exists with a chaotic attractor. Using the linear perturbation analysis, the prevalence of attractors in parameter space and the associated bifurcations are examined. Subcritical and supercritical Hopf bifurcations and abundance of Arnold tongues — a signature of mode locking phenomenon are found.
Synchronization System for Next Generation Light Sources
Energy Technology Data Exchange (ETDEWEB)
Zavriyev, Anton [MagiQ Technologies, Inc., Somerville, MA (United States)
2014-03-27
An alternative synchronization technique – one that would allow explicit control of the pulse train including its repetition rate and delay is clearly desired. We propose such a scheme. Our method is based on optical interferometry and permits synchronization of the pulse trains generated by two independent mode-locked lasers. As the next generation x-ray sources will be driven by a clock signal derived from a mode-locked optical source, our technique will provide a way to synchronize x-ray probe with the optical pump pulses.
Adaptive H∞ Chaos Anti-synchronization
International Nuclear Information System (INIS)
Ahn, Choon Ki
2010-01-01
A new adaptive H ∞ anti-synchronization (AHAS) method is proposed for chaotic systems in the presence of unknown parameters and external disturbances. Based on the Lyapunov theory and linear matrix inequality formulation, the AHAS controller with adaptive laws of unknown parameters is derived to not only guarantee adaptive anti-synchronization but also reduce the effect of external disturbances to an H ∞ norm constraint. As an application of the proposed AHAS method, the H ∞ anti-synchronization problem for Genesio–Tesi chaotic systems is investigated. (general)
DEFF Research Database (Denmark)
Guo, Yougui; Zeng, Ping; Li, Lijuan
2011-01-01
Virtual flux oriented direct power control (VFDPC) is combined space vector modulation (SVM) with PI of DC-link voltage, active power and reactive power to control the grid side converter in wind power generation system in this paper. VFDPC has reached good performances with PLL (phase lock loop......). First the mathematical models of grid side converter, LCL filter and phase lock loop are given. Then the control strategy of grid side converter-based wind power generation system is given in detail. Finally the simulation model is modeled consisting of power circuits, such as the grid side converter...... in wind power generation system....
Directory of Open Access Journals (Sweden)
S. Vaidyanathan
2014-11-01
Full Text Available This research work proposes a six-term novel 3-D jerk chaotic system with two exponential nonlinearities. This work also analyses system’s fundamental properties such as dissipativity, equilibria, Lyapunov exponents and Kaplan-Yorke dimension. The phase portraits of the jerk chaotic system simulated using MATLAB, depict the strange chaotic attractor of the system. For the parameter values and initial conditions chosen in this work, the Lyapunov exponents of the novel jerk chaotic system are obtained as L1 = 0.24519, L2 = 0 and L3 = −0.84571. Also, the Kaplan-Yorke dimension of the novel jerk chaotic system is obtained as DKY = 2.2899. Next, an adaptive backstepping controller is designed to stabilize the novel jerk chaotic system having two unknown parameters. Moreover, an adaptive backstepping controller is designed to achieve global chaos anti-synchronization of two identical novel jerk chaotic systems with two unknown system parameters. Finally, an electronic circuit realization of the novel jerk chaotic system is presented using SPICE to confirm the feasibility of the theoretical model.
Zhang, Quan; Li, Chaodong; Zhang, Jiantao; Zhang, Xu
2017-11-01
The macro–micro combined approach, as an effective way to realize trans-scale nano-precision positioning with multi-dimensions and high velocity, plays a significant role in integrated circuit manufacturing field. A 3-degree-of-freedoms (3-DOFs) macro–micro manipulator is designed and analyzed to compromise the conflictions among the large stroke, high precision and multi-DOFs. The macro manipulator is a 3-Prismatic-Revolute-Revolute (3-PRR) structure parallel manipulator which is driven by three linear ultrasonic motors. The dynamic model and the cross-coupling error based synchronized motion controller of the 3-PRR parallel manipulator are theoretical analyzed and experimental tested. To further improve the positioning accuracy, a 3-DOFs monolithic compliant manipulator actuated by three piezoelectric stack actuators is designed. Then a multilayer BP neural network based inverse kinematic model identifier is developed to perform the positioning control. Finally, by forming the macro–micro structure, the dual stage manipulator successfully achieved the positioning task from the point (2 mm, 2 mm, 0 rad) back to the original point (0 mm, 0 mm, 0 rad) with the translation errors in X and Y directions less than ±50 nm and the rotation error around Z axis less than ±1 μrad, respectively.
A PWM Controller of a Full Bridge Single-Phase Synchronous Inverter for Micro-Grid System
Rahman, Tawfikur; Motakabber, S. M. A.; Ibrahimy, M. I.; Raghib, Aliza ‘Aini Binti Md Ralib@ Md
2017-12-01
Nowadays, microgrid system technology is becoming popular for small area power management systems. It is essential to be less harmonic-distortion and high efficiency of the inverter for microgrid applications. Pulse width modulation (PWM) controller is a conventional switching control technique which is suitable to use in the microgrid connected power inverter system. The control method and algorithm of this technique are challenging, and different approaches are required to avoid the complexity for a customized solution of the microgrid application. This paper proposes a comparative analysis of different controller and their operational methods. A PWM controller is used to reduce the ripple voltage noise while a continuous current mode provides a small output ripple which gives steady-state error as zero on fundamental and cutoff frequency. To reduce the ripple current, higher frequency harmonic distortion, switching loss and phase noise, LC low pass filter is used on either side of input and output terminals. The proposed inverter is designed by MATLAB 2016a simulation software. A balanced load resistance (RL = 20.5 Ω) of star configuration and a dual input DC voltage of ± 35V are considered. In this design, the circuit parameters, the fundamental frequency of 50 Hz, the PWM duty cycle of 95%, the cutoff frequency of the switching controller of 33 kHz are considered. The inverter in this paper exhibits THD of 0.44% and overall efficiency approximately of 98%. The proposed inverter is expected to be suitable for microgrid applications.
Directory of Open Access Journals (Sweden)
Kamouni Meryem
2011-06-01
Full Text Available Abstract Background Multiple primary cancers have a low incidence particularly when cancers are synchronous. Few cases of synchronous head and neck cancer and breast carcinoma are reported in the literature. Case presentation We report here an exceptional case of a 47 years old Moroccan woman presenting two synchronous cancers, the first in the nasopharynx and the second in the breast. The patient was treated successfully with a combined strategy associating chemotherapy, radiation therapy, and surgery. She remains disease free after 27 months of follow up. Conclusions Treatment strategy in the case of multiple primary cancers remains controversial because of the variety of presentations; initial aggressive treatment reports good results.
Synchronization Analysis of the Supermarket Refrigeration System
DEFF Research Database (Denmark)
Wisniewski, Rafal; Chen, Liang; Larsen, Lars Finn Sloth
2009-01-01
consumption. The paper focuses on synchronization dynamics of the refrigeration system modeled as a piecewiseaffine switched system. Stability analysis is performed bygluing the subsystems and polyhedra together to form a single dynamical system defined on a coherent state space. Then, system behavior......The supermarket refrigeration system typically has a distributed control structure, which neglects interactions between its subsystems. These interactions from time to time lead to a synchronization operation of the display-cases which causes an inferior control performance and increased energy...... is analyzed using the bifurcation and chaos theory. It is demonstrated that the system can have a complex chaotic behavior, which is far from the synchronization. This shows that making the system chaotic is a good choice for a de-synchronization strategy. The positive maximum Lyapunov exponent is usually...
Projective synchronization based on suitable separation
International Nuclear Information System (INIS)
Li Guohui; Xiong Chuan; Sun Xiaonan
2007-01-01
A new approach for constructing a projective-synchronized chaotic slave system is proposed in this paper. This method is based on suitable separation by decomposing the system as the linear part and the nonlinear one. From matrix measure theory, some simple but efficient criteria are derived for projective synchronization of chaotic system. Numerical simulations for the Lorenz system show that this control method works very well
Asynchronized synchronous machines
Botvinnik, M M
1964-01-01
Asynchronized Synchronous Machines focuses on the theoretical research on asynchronized synchronous (AS) machines, which are "hybrids of synchronous and induction machines that can operate with slip. Topics covered in this book include the initial equations; vector diagram of an AS machine; regulation in cases of deviation from the law of full compensation; parameters of the excitation system; and schematic diagram of an excitation regulator. The possible applications of AS machines and its calculations in certain cases are also discussed. This publication is beneficial for students and indiv
Directory of Open Access Journals (Sweden)
Feng Xing
2018-03-01
Full Text Available The maglev linear motor has three degrees of motion freedom, which are respectively realized by the thrust force in the x-axis, the levitation force in the z-axis and the torque around the y-axis. Both the thrust force and levitation force can be seen as the sum of the forces on the three windings. The resultant thrust force and resultant levitation force are independently controlled by d-axis current and q-axis current respectively. Thus, the commonly used dq transformation control strategy is suitable for realizing the control of the resultant force, either thrust force and levitation force. However, the forces on the three windings also generate additional torque because they do not pass the mover mass center. To realize the maglev system high-precision control, a maglev linear motor with a new structure is proposed in this paper to decrease this torque. First, the electromagnetic model of the motor can be deduced through the Lorenz force formula. Second, the analytic method and finite element method are used to explore the reason of this additional torque and what factors affect its change trend. Furthermore, a maglev linear motor with a new structure is proposed, with two sets of 90 degrees shifted winding designed on the mover. Under such a structure, the mover position dependent periodic part of the additional torque can be offset. Finally, the theoretical analysis is validated by the simulation result that the additionally generated rotating torque can be offset with little fluctuation in the proposed new-structure maglev linear motor. Moreover, the control system is built in MATLAB/Simulink, which shows that it has small thrust ripple and high-precision performance.
Energy Technology Data Exchange (ETDEWEB)
Prasad, Mata [ABB, New Delhi (India); Rao, L.V.; Chakravorty, S.; Moni, R.S.; Dass, R. [National Thermal Power Corporation Ltd., New Delhi (India); Mishra, R.B.; Tripathi, D.B. [Powergrid (India); Bjorklund, Hans; Duchen, Hugo; Westling, Soren [ABB Power Systems, Ludvika (Sweden)
1994-12-31
The Rihand-Delhi Hvdc transmission system comprises of two poles in bipolar mode, each of 750 MW nominal capacity. The length of the transmission line is 814 km and the main objective of the link is the transmission of bulk power from the Singrauli/Rihand thermal generating complex to the major load centers near the National Capital region. As in all major Hvdc schemes, the Rihand-Delhi Hvdc project has also been provided with a SSO damping controller which was extensively tested in the simulator prior to installation. This paper describes some of the important field tests conducted to ascertain actual performance and compares the same with corresponding simulator cases. Also covered is the performance of the frequency controller. (author) 3 refs., 9 figs.
Permanent magnet synchronous and brushless DC motor drives
Ramu, Krishnan
2009-01-01
Presents an introduction to machines, power devices, inverters, and control. This book covers pm synchronous machines, including modeling, implementation, control strategies, flux weakening operations, parameter sensitivity, sensorless control, and intelligent control applications.
Alnabelsi, Talal; Al-Hussaini, Ali; Owens, David
2015-03-01
Undergraduate otolaryngology teaching in the UK is generally limited primarily due to curriculum time constraints with traditional face-to-face (FtF) teaching being restrained by the limitations of time and location. Advances in network technology have opened up new doors for the delivery of teaching in the form of online learning. This study compares a traditional instructor-led lecture with synchronous e-learning (SeL) using otolaryngological emergencies teaching as an educational intervention. A randomised controlled trial was designed involving two groups of medical students attending an otolaryngology emergencies management lecture: one present FtF and the other viewing the streamed lecture online. The primary outcome measure was improvement between pre-and post-lecture test scores. Secondary outcomes comprised the students' ratings of the lecture on a Likert-type scale. Students in both groups had improved test scores following the lecture (p teaching in improving students' knowledge on the management of otolaryngological emergencies, and that it is generally positively perceived by medical undergraduates. This highlights the potential utility of e-learning technology in undergraduate otolaryngology training.
Directory of Open Access Journals (Sweden)
Marni Wesner
Full Text Available This pilot study aimed to inform future research evaluating the effectiveness of Platelet Rich Plasma (PRP injection for tendinopathy.Randomized control trial (RCT and synchronous observational cohort studies. For the RCT, consecutive consenting patients treated at an academic sports medicine clinic were randomly assigned to either a PRP or placebo control group.The Glen Sather Sport Medicine Clinic, Edmonton, Canada.The RCT included 9 participants with rotator cuff tendinopathy. The cohort study included 178 participants with a variety of tendinopathies.Patients receiving PRP were injected with 4 ml of platelets into the supraspinatus and/or infraspinatus, while patients in the placebo group were injected with 4 ml of saline. All participants undertook a 3-month standardized, home-based, daily exercise program.Participants in the RCT were re-evaluated 3, and 6 months post-injection. Change scores before and after injection on pain, disability and MRI-documented pathology outcomes were compared. In the cohort study, pain and disability were measured at 1, 2 and 3 months post-injection.For the RCT, 7 participants received PRP and 2 received placebo injections. Patients receiving PRP reported clinically important improvements in pain (>1.5/10 on VAS, disability (>15 point DASH change, and tendon pathology while those receiving placebo injections did not. In the observational cohort, statistically and clinically significant improvements in pain and disability were observed.This pilot study provides information for planning future studies of PRP effectiveness. Preliminary results indicate intratendinous, ultrasound-guided PRP injection may lead to improvements in pain, function, and MRI-documented tendon pathology.Controlled-Trials.com ISRCTN68341698.
Directory of Open Access Journals (Sweden)
Vaidyanathan Sundarapandian
2014-12-01
Full Text Available In this research work, a twelve-term novel 5-D hyperchaotic Lorenz system with three quadratic nonlinearities has been derived by adding a feedback control to a ten-term 4-D hyperchaotic Lorenz system (Jia, 2007 with three quadratic nonlinearities. The 4-D hyperchaotic Lorenz system (Jia, 2007 has the Lyapunov exponents L1 = 0.3684,L2 = 0.2174,L3 = 0 and L4 =−12.9513, and the Kaplan-Yorke dimension of this 4-D system is found as DKY =3.0452. The 5-D novel hyperchaotic Lorenz system proposed in this work has the Lyapunov exponents L1 = 0.4195,L2 = 0.2430,L3 = 0.0145,L4 = 0 and L5 = −13.0405, and the Kaplan-Yorke dimension of this 5-D system is found as DKY =4.0159. Thus, the novel 5-D hyperchaotic Lorenz system has a maximal Lyapunov exponent (MLE, which is greater than the maximal Lyapunov exponent (MLE of the 4-D hyperchaotic Lorenz system. The 5-D novel hyperchaotic Lorenz system has a unique equilibrium point at the origin, which is a saddle-point and hence unstable. Next, an adaptive controller is designed to stabilize the novel 5-D hyperchaotic Lorenz system with unknown system parameters. Moreover, an adaptive controller is designed to achieve global hyperchaos synchronization of the identical novel 5-D hyperchaotic Lorenz systems with unknown system parameters. Finally, an electronic circuit realization of the novel 5-D hyperchaotic Lorenz system using SPICE is described in detail to confirm the feasibility of the theoretical model.
Synchronization in complex networks
Energy Technology Data Exchange (ETDEWEB)
Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.
2007-12-12
Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.
The patent describes a synchronous direct current (dc) power supply which has the power supply input drive synchronized with the pulse repetition...frequency (PRF) of the amplifying or load circuit requiring the dc power for operation. This limits the occurrence of ripple components in the power ... supply output to the spectral positions of the PRF lines, eliminating ripple interference with signal processing in the load. An astable multivibrator is
Observations on oestrus synchronization in Zebu cattle
International Nuclear Information System (INIS)
Galina, C.S.; Porras, A.; Navarro Fierro, R.; Wild, C.; Orihuela, A.; Hernandez, C.
1990-01-01
A series of experiments were conducted to test the efficacy of drugs used to synchronize oestrus in Zebu cattle. Fertility (conception rates) in adult cows following synchronized (PGF 2α ) and non-synchronized oestruses and AI were found to be 22% and 27% respectively; fertility after natural mating (NM) was 47% for cows synchronized with PGF 2α and 41% for control animals. After a 60 day breeding period NM groups were 13% more fertile overall than the AI groups (P 2α were compared in the same herd, no differences in fertility were found, although groups treated with progesterone showed a higher incidence of oestrus than those administered PGF 2α (60 vs. 27%, P<0.01). (author). 22 refs, 1 fig., 6 tabs
Knox, R V; Webel, S K; Swanson, M; Johnston, M E; Kraeling, R R
2017-10-01
Estrus and ovulation responses in Matrix-treated gilts may affect ovulation synchrony in response to triptorelin. In experiment 1, estrus and ovulation measures at 12h intervals after last Matrix feeding (LMF) were analyzed. For the 398 gilts that displayed estrus, 87.4% were detected on Days 6-8 after LMF. Duration of estrus was 24-60h for 85.6% of gilts and negatively correlated with interval from LMF to estrus (r=-0.53, Pgilts (n=96) received intravaginal treatment with 2mL of gel containing placebo (Control) at 96h, 200μg of triptorelin at 96h (TRP96), 120h (TRP120) or 144h (TRP144) after LMF. Estrus measures did not differ (P>0.10) among treatments. The proportion of gilts ovulating 32-56h after treatment was greater for TRP120 and TRP144 (Pgilts (n=86) received placebo (Control), 100μg (TRP100), 200μg (TRP200), or 400μg (TRP400) of triptorelin at 120h after LMF. There was no effect of treatment (P>0.10) on estrus or on interval from LMF to estrus. The proportion of gilts ovulating by 40, 48 and 56h after treatment increased (Pgilts receiving 100-400μg of triptorelin at 120h after LMF had the greatest ovulation synchrony 24-48h following treatment. These studies provide important information for developing a procedure for a single insemination in synchronized gilts. Copyright © 2017 Elsevier B.V. All rights reserved.
Suppression of synchronous resonance for VSGs
DEFF Research Database (Denmark)
Yang, Dongsheng; Wu, Heng; Wang, Xiongfei
2017-01-01
The virtual synchronous generator (VSG) is an attractive interfacing technique for high-penetration renewable generation. By incorporating the inertia control, the grid-connected voltage-source converter can behave in a similar way with the SGs, which is helpful to enhance the stability of the po......The virtual synchronous generator (VSG) is an attractive interfacing technique for high-penetration renewable generation. By incorporating the inertia control, the grid-connected voltage-source converter can behave in a similar way with the SGs, which is helpful to enhance the stability...... of the power system. However, it is reported that the synchronous frequency resonance (SFR) can be aroused in the VSG due to the resonance peaks in the power control loops at the fundamental frequency. By modelling the power control loop in the dq domain, the mechanism underlying the SFR is studied. It reveals...
De-synchronization of the Distributed Refrigeration System
DEFF Research Database (Denmark)
Chen, Liang; Wisniewski, Rafal
2010-01-01
The supermarket refrigeration system typically has a distributed control structure, which simple and flexible, however, neglects interactions between its subsystems. Practice shows that these interactions lead to a synchronous operation of the display cases. It causes excessive wear...... on the compressors and increased energy consumption. The paper focuses on the synchronization analysis and de-synchronization control. The supermarket refrigeration system is modeled as a piecewise-affine switched system. The system behavior is decomposed such that synchronization analysis can be completed by using...... performance and can deal with the large scale refrigeration system with different system parameters in the display cases....
Compound Synchronization of Four Chaotic Complex Systems
Directory of Open Access Journals (Sweden)
Junwei Sun
2015-01-01
Full Text Available The chaotic complex system is designed from the start of the chaotic real system. Dynamical properties of a chaotic complex system in complex space are investigated. In this paper, a compound synchronization scheme is achieved for four chaotic complex systems. According to Lyapunov stability theory and the adaptive control method, four chaotic complex systems are considered and the corresponding controllers are designed to realize the compound synchronization scheme. Four novel design chaotic complex systems are given as an example to verify the validity and feasibility of the proposed control scheme.
Energy Technology Data Exchange (ETDEWEB)
Silva, J.C.; Colvara, L.D. [Universidade Estadual Paulista (FEIS/UNESP), Ilha Solteira, SP (Brazil). Dept. de Engenharia Eletrica], Emails: jadiel_silva@hotmail.com, laurence@dee.feis.unesp.br
2009-07-01
The problem of stability of electric power systems, from the standpoint of ability to sync and how FACTS (Flexible Alternating Current Transmission Systems) devices affect this ability in particular the TSCS (Thyristor Controlled Series Compensator) inserted into an environment multi machine, is addressed. The effects of this device on the power synchronizing are considered through analysis of the matrix admittance of the bar, focusing on the transfer admittances between machines.
2010-04-01
... Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and Products Containing Same... synchronous dynamic random access memory controllers and products containing same by reason of infringement of... semiconductor chips having synchronous dynamic random access memory controllers and products containing same...
Master-Slave Synchronization of 4D Hyperchaotic Rabinovich Systems
Directory of Open Access Journals (Sweden)
Ke Ding
2018-01-01
Full Text Available This paper is concerned with master-slave synchronization of 4D hyperchaotic Rabinovich systems. Compared with some existing papers, this paper has two contributions. The first contribution is that the nonlinear terms of error systems remained which inherit nonlinear features from master and slave 4D hyperchaotic Rabinovich systems, rather than discarding nonlinear features of original hyperchaotic Rabinovich systems and eliminating those nonlinear terms to derive linear error systems as the control methods in some existing papers. The second contribution is that the synchronization criteria of this paper are global rather than local synchronization results in some existing papers. In addition, those synchronization criteria and control methods for 4D hyperchaotic Rabinovich systems are extended to investigate the synchronization of 3D chaotic Rabinovich systems. The effectiveness of synchronization criteria is illustrated by three simulation examples.
Inverse synchronization of coupled fractional-order systems through ...
Indian Academy of Sciences (India)
A general explicit coupling via an open-plus-closed-loop control for inverse synchronization of two .... derivative [51], which is in essence an improved version of Adams–Bashforth–Moulton algorithm. The following is a ... OPCL control has found its applications in the synchronization of both integer-order and fractional-order ...
Synchronization of Neural Networks of Neutral Type with Stochastic Perturbation
Park, Ju H.; Kwon, O. M.
In this letter, the problem of feedback controller design to achieve synchronization for neural network of neutral type with stochastic perturbation is considered. Based on Lyapunov method and LMI (linear matrix inequality) framework, the goal of this letter is to derive an existence criterion of the controller for the synchronization between master and response networks.
Synchronization of mobile chaotic oscillator networks
International Nuclear Information System (INIS)
Fujiwara, Naoya; Kurths, Jürgen; Díaz-Guilera, Albert
2016-01-01
We study synchronization of systems in which agents holding chaotic oscillators move in a two-dimensional plane and interact with nearby ones forming a time dependent network. Due to the uncertainty in observing other agents' states, we assume that the interaction contains a certain amount of noise that turns out to be relevant for chaotic dynamics. We find that a synchronization transition takes place by changing a control parameter. But this transition depends on the relative dynamic scale of motion and interaction. When the topology change is slow, we observe an intermittent switching between laminar and burst states close to the transition due to small noise. This novel type of synchronization transition and intermittency can happen even when complete synchronization is linearly stable in the absence of noise. We show that the linear stability of the synchronized state is not a sufficient condition for its stability due to strong fluctuations of the transverse Lyapunov exponent associated with a slow network topology change. Since this effect can be observed within the linearized dynamics, we can expect such an effect in the temporal networks with noisy chaotic oscillators, irrespective of the details of the oscillator dynamics. When the topology change is fast, a linearized approximation describes well the dynamics towards synchrony. These results imply that the fluctuations of the finite-time transverse Lyapunov exponent should also be taken into account to estimate synchronization of the mobile contact networks.
Synchronizing weighted automata
Directory of Open Access Journals (Sweden)
Szabolcs Iván
2014-05-01
Full Text Available We introduce two generalizations of synchronizability to automata with transitions weighted in an arbitrary semiring K=(K,+,*,0,1. (or equivalently, to finite sets of matrices in K^nxn. Let us call a matrix A location-synchronizing if there exists a column in A consisting of nonzero entries such that all the other columns of A are filled by zeros. If additionally all the entries of this designated column are the same, we call A synchronizing. Note that these notions coincide for stochastic matrices and also in the Boolean semiring. A set M of matrices in K^nxn is called (location-synchronizing if M generates a matrix subsemigroup containing a (location-synchronizing matrix. The K-(location-synchronizability problem is the following: given a finite set M of nxn matrices with entries in K, is it (location-synchronizing? Both problems are PSPACE-hard for any nontrivial semiring. We give sufficient conditions for the semiring K when the problems are PSPACE-complete and show several undecidability results as well, e.g. synchronizability is undecidable if 1 has infinite order in (K,+,0 or when the free semigroup on two generators can be embedded into (K,*,1.
Mean Square Synchronization of Stochastic Nonlinear Delayed Coupled Complex Networks
Directory of Open Access Journals (Sweden)
Chengrong Xie
2013-01-01
Full Text Available We investigate the problem of adaptive mean square synchronization for nonlinear delayed coupled complex networks with stochastic perturbation. Based on the LaSalle invariance principle and the properties of the Weiner process, the controller and adaptive laws are designed to ensure achieving stochastic synchronization and topology identification of complex networks. Sufficient conditions are given to ensure the complex networks to be mean square synchronization. Furthermore, numerical simulations are also given to demonstrate the effectiveness of the proposed scheme.
Optimistic barrier synchronization
Nicol, David M.
1992-01-01
Barrier synchronization is fundamental operation in parallel computation. In many contexts, at the point a processor enters a barrier it knows that it has already processed all the work required of it prior to synchronization. The alternative case, when a processor cannot enter a barrier with the assurance that it has already performed all the necessary pre-synchronization computation, is treated. The problem arises when the number of pre-sychronization messages to be received by a processor is unkown, for example, in a parallel discrete simulation or any other computation that is largely driven by an unpredictable exchange of messages. We describe an optimistic O(log sup 2 P) barrier algorithm for such problems, study its performance on a large-scale parallel system, and consider extensions to general associative reductions as well as associative parallel prefix computations.
Directory of Open Access Journals (Sweden)
Ivonne Yznaga Blanco
2011-02-01
Full Text Available El motor sincrónico de imán permanente posee características especiales para operar a velocidad variableque lo distinguen de los otros tipos de motores de corriente alterna (CA. Debido a la configuración especialdel rotor, su salida y su relativamente alta inductancia, este motor es adecuado para operar a flujo debilitadoen un amplio diapasón, ofreciendo además una mayor relación momento/volumen. Existen muchas técnicasreportadas en la literatura para el seguimiento de la corriente y el momento. La técnica de control momento/corriente es una de ellas .y puede ser a su vez, subdividida en directa, instantánea e indirecta. Este trabajohace un análisis de dos de ellas: La de máximo momento por ampere con control PWM y la del controlinstantáneo del momento. Se discuten también las múltiples ventajas de utilizar estas técnicas. The interior permanent magnet synchronous motor (IPMSM possesses special features for adjustable speedoperation that distinguish it from other type of AC machines. Because of its special rotor configuration, polesaliency and relatively large armature inductances, the IPM is also more suitable for an extended speed rangeoperation by the flux weakening control, in addition to the higher torque/volume it can offer [1]. There are manytechniques, for controlling the actual torque or current to follow their references, reported in the literature forthis type of motor. The torque/current control technique is one of them and can be classified into direct,instantaneous and indirect torque controls. This work reviewed two of them, i.e. maximum torque-per-ampere(MTPA techniques in PWM current control and Instantaneous torque control for Interior Permanent MagnetSynchronous Motor. The multiple adventages of the use of this type of techniques are disscused too.
A universal projective synchronization of general autonomous ...
Indian Academy of Sciences (India)
This paper investigates the generalized projective synchronization in general autonomous chaotic system. A universal controller is designed and the effectiveness is verified via theoretical analysis and numerical simulations. The controller design is irrelevant to concrete system structure and initial values. It has strong ...
Synchronization analysis of coloured delayed networks under ...
Indian Academy of Sciences (India)
This paper investigates synchronization of coloured delayed networks under decentralized pinning intermittent control. To begin with, the time delays are taken into account in the coloured networks. In addition, we propose a decentralized pinning intermittent control for coloured delayed networks, which is different from that ...
Chaotic synchronization of two complex nonlinear oscillators
Energy Technology Data Exchange (ETDEWEB)
Mahmoud, Gamal M. [Department of Mathematics, Faculty of Science, Assiut University, Assiut 71516 (Egypt)], E-mail: gmahmoud@aun.edu.eg; Mahmoud, Emad E. [Department of Mathematics, Faculty of Science, Sohag University (Egypt)], E-mail: emad_eluan@yahoo.com; Farghaly, Ahmed A. [Department of Mathematics, Faculty of Science, Assiut University, Assiut 71516 (Egypt)], E-mail: ahmed_1_66@yahoo.com; Aly, Shaban A. [Department of Mathematics, Faculty of Science, Al-Azhar University, Assiut 71511 (Egypt)], E-mail: shhaly12@yahoo.com
2009-12-15
Synchronization is an important phenomenon commonly observed in nature. It is also often artificially induced because it is desirable for a variety of applications in physics, applied sciences and engineering. In a recent paper [Mahmoud GM, Mohamed AA, Aly SA. Strange attractors and chaos control in periodically forced complex Duffing's oscillators. Physica A 2001;292:193-206], a system of periodically forced complex Duffing's oscillators was introduced and shown to display chaotic behavior and possess strange attractors. Such complex oscillators appear in many problems of physics and engineering, as, for example, nonlinear optics, deep-water wave theory, plasma physics and bimolecular dynamics. Their connection to solutions of the nonlinear Schroedinger equation has also been pointed out. In this paper, we study the remarkable phenomenon of chaotic synchronization on these oscillator systems, using active control and global synchronization techniques. We derive analytical expressions for control functions and show that the dynamics of error evolution is globally stable, by constructing appropriate Lyapunov functions. This means that, for a relatively large set initial conditions, the differences between the drive and response systems vanish exponentially and synchronization is achieved. Numerical results are obtained to test the validity of the analytical expressions and illustrate the efficiency of these techniques for inducing chaos synchronization in our nonlinear oscillators.
Chaotic synchronization of two complex nonlinear oscillators
International Nuclear Information System (INIS)
Mahmoud, Gamal M.; Mahmoud, Emad E.; Farghaly, Ahmed A.; Aly, Shaban A.
2009-01-01
Synchronization is an important phenomenon commonly observed in nature. It is also often artificially induced because it is desirable for a variety of applications in physics, applied sciences and engineering. In a recent paper [Mahmoud GM, Mohamed AA, Aly SA. Strange attractors and chaos control in periodically forced complex Duffing's oscillators. Physica A 2001;292:193-206], a system of periodically forced complex Duffing's oscillators was introduced and shown to display chaotic behavior and possess strange attractors. Such complex oscillators appear in many problems of physics and engineering, as, for example, nonlinear optics, deep-water wave theory, plasma physics and bimolecular dynamics. Their connection to solutions of the nonlinear Schroedinger equation has also been pointed out. In this paper, we study the remarkable phenomenon of chaotic synchronization on these oscillator systems, using active control and global synchronization techniques. We derive analytical expressions for control functions and show that the dynamics of error evolution is globally stable, by constructing appropriate Lyapunov functions. This means that, for a relatively large set initial conditions, the differences between the drive and response systems vanish exponentially and synchronization is achieved. Numerical results are obtained to test the validity of the analytical expressions and illustrate the efficiency of these techniques for inducing chaos synchronization in our nonlinear oscillators.
Butz, Nikolaus T.; Stupnisky, Robert H.; Pekrun, Reinhard; Jensen, Jason L.; Harsell, Dana M.
2016-01-01
Synchronous hybrid delivery (simultaneously teaching on-campus and online students using Web conferencing) is becoming more common in higher education. However, little is known about students' emotions in these environments. Although often overlooked, emotions are fundamental antecedents of success. This study longitudinally examined the role of…
Zhang, Meirong; Saberi, Ali; Stoorvogel, Antonie Arij; Grip, H°avard Fjær
2016-01-01
We consider almost output synchronization for directed heterogeneous time-varying networks where agents are non-introspective (i.e., agents have no access to their own states or outputs) in the presence of external disturbances. The nonlinear agents have a triangular structure and are globally
CMAC-based adaptive backstepping synchronization of uncertain chaotic systems
International Nuclear Information System (INIS)
Lin, C.-M.; Peng, Y.-F.; Lin, M.-H.
2009-01-01
This study proposes an adaptive backstepping control system for synchronizing uncertain chaotic system by using cerebellar model articulation controller (CMAC). CMAC is a nonlinear network with simple computation, good generalization capability and fast learning property. The proposed CMAC-based adaptive backstepping control (CABC) system uses backstepping method and adaptive cerebellar model articulation controller (ACMAC) for synchronizing uncertain chaotic system. Finally, simulation results for the Genesio system are presented to illustrate the effectiveness of the proposed control system.
Novel synchronization technique for two parallel connected sparkgap switches.
Kumar, Rohit; Mitra, S; Patel, A; Dwivedi, Rajesh; Kolge, T; Sharma, Ranjeet Archana; Chakravarthy, D P
2012-08-01
In this article a novel way of synchronizing two parallel connected sparkgap switches with accuracies of 1-5 ns for high frequency pulsed power applications is described. The circuit design of a synchronized sparkgap switch circuit is discussed. The circuit uses a combination of one master sparkgap and a set of inductor and capacitors to synchronize two sparkgaps and can be controlled via an IGBT switch. Critical issues for circuit design are presented together with analytical calculations and simulations. Experimental verification of the novel topology is carried out in a prototype experimental setup. Results showing nanosecond level of accuracy in synchronization are reported in this paper along with simulations and analysis.
Frequency Stability Improvement of Low Inertia Systems Using Synchronous Condensers
DEFF Research Database (Denmark)
Nguyen, Ha Thi; Yang, Guangya; Nielsen, Arne Hejde
2016-01-01
of converter interfaced components (wind turbine, HVDC, and Photovoltaic) may have negative effects on the stability of the power system. These components do not have enough inertia response to control frequency excursion, so the power grid can depend on few synchronous machines for frequency regulation...... turbine penetration, governor responsibility of synchronous generators, and disturbance are simulated to examine the impact of highlevel renewable energy integration on the system frequency characteristics. The effect of synchronous condensers for the frequency stability enhancement is investigated....... It can be concluded from the comparative simulation results that synchronous condenser demonstrates a satisfactory performance for improving the system frequency stability....
Adaptive elimination of synchronization in coupled oscillator
International Nuclear Information System (INIS)
Zhou, Shijie; Lin, Wei; Ji, Peng; Feng, Jianfeng; Zhou, Qing; Kurths, Jürgen
2017-01-01
We present here an adaptive control scheme with a feedback delay to achieve elimination of synchronization in a large population of coupled and synchronized oscillators. We validate the feasibility of this scheme not only in the coupled Kuramoto’s oscillators with a unimodal or bimodal distribution of natural frequency, but also in two representative models of neuronal networks, namely, the FitzHugh–Nagumo spiking oscillators and the Hindmarsh–Rose bursting oscillators. More significantly, we analytically illustrate the feasibility of the proposed scheme with a feedback delay and reveal how the exact topological form of the bimodal natural frequency distribution influences the scheme performance. We anticipate that our developed scheme will deepen the understanding and refinement of those controllers, e.g. techniques of deep brain stimulation, which have been implemented in remedying some synchronization-induced mental disorders including Parkinson disease and epilepsy. (paper)
Adaptive elimination of synchronization in coupled oscillator
Zhou, Shijie; Ji, Peng; Zhou, Qing; Feng, Jianfeng; Kurths, Jürgen; Lin, Wei
2017-08-01
We present here an adaptive control scheme with a feedback delay to achieve elimination of synchronization in a large population of coupled and synchronized oscillators. We validate the feasibility of this scheme not only in the coupled Kuramoto’s oscillators with a unimodal or bimodal distribution of natural frequency, but also in two representative models of neuronal networks, namely, the FitzHugh-Nagumo spiking oscillators and the Hindmarsh-Rose bursting oscillators. More significantly, we analytically illustrate the feasibility of the proposed scheme with a feedback delay and reveal how the exact topological form of the bimodal natural frequency distribution influences the scheme performance. We anticipate that our developed scheme will deepen the understanding and refinement of those controllers, e.g. techniques of deep brain stimulation, which have been implemented in remedying some synchronization-induced mental disorders including Parkinson disease and epilepsy.
Method of synchronizing independent functional unit
Energy Technology Data Exchange (ETDEWEB)
Kim, Changhoan
2018-03-13
A system for synchronizing parallel processing of a plurality of functional processing units (FPU), a first FPU and a first program counter to control timing of a first stream of program instructions issued to the first FPU by advancement of the first program counter; a second FPU and a second program counter to control timing of a second stream of program instructions issued to the second FPU by advancement of the second program counter, the first FPU is in communication with a second FPU to synchronize the issuance of a first stream of program instructions to the second stream of program instructions and the second FPU is in communication with the first FPU to synchronize the issuance of the second stream program instructions to the first stream of program instructions.
Indian Academy of Sciences (India)
time. Both the number of nodes and the edges connecting the nodes can vary with time. Such a time-varying topology can occur in social networks, computer networks, WWW, biological systems, spread of epidemics etc. Here, we investigate the synchronization properties of networks with time-varying structure and compare.
Indian Academy of Sciences (India)
We study the synchronization of coupled dynamical systems on networks. The dynamics is governed by a local nonlinear oscillator for each node of the network and interactions connecting different nodes via the links of the network. We consider existence and stability conditions for both single- and multi-cluster ...
Nishi, Daisuke; Su, Kuan-Pin; Usuda, Kentaro; Chiang, Yi-Ju Jill; Guu, Tai-Wei; Hamazaki, Kei; Nakaya, Naoki; Sone, Toshimasa; Sano, Yo; Tachibana, Yoshiyuki; Ito, Hiroe; Isaka, Keiich; Hashimoto, Kenji; Hamazaki, Tomohito; Matsuoka, Yutaka J
2016-09-15
Maternal depression can be harmful to both mothers and their children. Omega-3 polyunsaturated fatty acid (PUFA) supplementation has been investigated as an alternative intervention for pregnant women with depressive symptoms because of the supporting evidence from clinical trials in major depression, the safety advantage, and its anti-inflammatory and neuroplasticity effects. This study examines the efficacy of omega-3 PUFA supplementation for pregnant women with depressive symptoms in Taiwan and Japan, to provide evidence available for Asia. The rationale and protocol of this trial are reported here. The Synchronized Trial on Expectant Mothers with Depressive Symptoms by Omega-3 PUFAs (SYNCHRO) is a multicenter, double-blind, parallel group, randomized controlled trial. Participants will be randomized to either the omega-3 PUFAs arm (1,200 mg eicosapentaenoic acid and 600 mg docosahexaenoic acid daily) or placebo arm. Primary outcome is total score on the Hamilton Rating Scale for Depression (HAMD) at 12 weeks after the start of the intervention. We will randomize 56 participants to have 90 % power to detect a 4.7-point difference in mean HAMD scores with omega-3 PUFAs compared with placebo. Because seafood consumption varies across countries and this may have a major effect on the efficacy of omega-3 PUFA supplementation, 56 participants will be recruited at each site in Taiwan and Japan, for a total number of 112 participants. Secondary outcomes include depressive symptoms at 1 month after childbirth, diagnosis of major depressive disorder, changes in omega-3 PUFAs concentrations and levels of biomarkers at baseline and at 12 weeks' follow-up, and standard obstetric outcomes. Data analyses will be by intention to treat. The trial was started in June 2014 and is scheduled to end in February 2018. The trial is expected to provide evidence that can contribute to promoting mental health among mothers and children in Asian populations. Clinicaltrials.gov: NCT
Composite synchronization of three eccentric rotors driven by induction motors in a vibrating system
Kong, Xiangxi; Chen, Changzheng; Wen, Bangchun
2018-03-01
This paper addresses the problem of composite synchronization of three eccentric rotors (ERs) driven by induction motors in a vibrating system. The composite synchronous motion of three ERs is composed of the controlled synchronous motion of two ERs and the self-synchronous motion of the third ER. Combining an adaptive sliding mode control (ASMC) algorithm with a modified master-slave control structure, the controllers are designed to implement controlled synchronous motion of two ERs with zero phase difference. Based on Lyapunov stability theorem and Barbalat's lemma, the stability of the designed controllers is verified. On basis of controlled synchronization of two ERs, self-synchronization of the third ER is introduced to implement composite synchronous motion of three ERs. The feasibility of the proposed composite synchronization method is analyzed by numerical method. The effects of motor and structure parameters on composite synchronous motion are discussed. Experiments on a vibrating test bench driven by three ERs are operated to validate the effectiveness of the proposed composite synchronization method, including a comparison with self-synchronization method.
Adaptive Synchronization of Fractional Neural Networks with Unknown Parameters and Time Delays
Directory of Open Access Journals (Sweden)
Weiyuan Ma
2014-12-01
Full Text Available In this paper, the parameters identification and synchronization problem of fractional-order neural networks with time delays are investigated. Based on some analytical techniques and an adaptive control method, a simple adaptive synchronization controller and parameter update laws are designed to synchronize two uncertain complex networks with time delays. Besides, the system parameters in the uncertain network can be identified in the process of synchronization. To demonstrate the validity of the proposed method, several illustrative examples are presented.
Synchronization enhancement via an oscillatory bath in a network of ...
Indian Academy of Sciences (India)
2015-02-05
Feb 5, 2015 ... The robustness of synchronization strategy is tested using a local and global injection of Gaussian white noise in the network. The control gain parameter of the bath coupling can modulate the occurrence of synchronization in the network without prior requirement of direct coupling among all the cells.
Function projective synchronization of identical and non-identical ...
Indian Academy of Sciences (India)
... synchronization; modified finance system; Shimizu–Morioka system; active control technique. PACS Nos 05.45.Pq; 05.45.Gg; 05.45.Ac. 1. Introduction. Chaos synchronization is an important subject both theoretically and practically, for applications requiring oscillation out of chaos, machine and building structure analysis,.
Lag synchronization of chaotic systems with time-delayed linear ...
Indian Academy of Sciences (India)
In this paper, the lag synchronization of chaotic systems with time-delayed linear terms via impulsive control is investigated. Based on the stability theory of impulsive delayed differential equations, some sufficient conditions are obtained guaranteeing the synchronized behaviours between two delayed chaotic systems.
Increased-order generalized synchronization of chaotic and ...
Indian Academy of Sciences (India)
Keywords. Active control; increased-order synchronization; hyperchaos; Lorenz system. PACS Nos 05.45.Pq; 05.45.Gg; 05.45.Ac. 1. Introduction. Chaos synchronization has gained a lot of attention over the last two decades [1] due to its potential applications in vast areas of physics and engineering sciences. Synchroniza-.
Lag synchronization of chaotic systems with time-delayed linear
Indian Academy of Sciences (India)
In this paper, the lag synchronization of chaotic systems with time-delayed linear terms via impulsive control is investigated. Based on the stability theory of impulsive delayed differential equations, some sufficient conditions are obtained guaranteeing the synchronized behaviours between two delayed chaotic systems.
RBF neural network based H∞ H∞ H∞ synchronization for ...
Indian Academy of Sciences (India)
In this paper, we propose a new H ∞ synchronization strategy, called a Radial Basis Function Neural Network H ∞ synchronization (RBFNNHS) strategy, for ... Based on this neural network and linear matrix inequality (LMI) formulation, the RBFNNHS controller and the learning laws are presented to reduce the effect of ...
On adaptive modified projective synchronization of a supply chain ...
Indian Academy of Sciences (India)
In this paper, the synchronization problem of a chaotic supply chain management system is studied. A novel adaptive modified projective synchronization method is introduced to control the behaviour of the leader supply chain system by a follower chaotic system and to adjust the leader system parameters until the ...
Synchronizing the noise-perturbed Lue chaotic system
International Nuclear Information System (INIS)
Zhang Yan; Chen Shihua; Zhou Hong
2009-01-01
In this paper, synchronization between unidirectionally coupled Lue chaotic systems with noise perturbation is investigated theoretically and numerically. Sufficient conditions of synchronization between these noise-perturbed systems are established by means of the so-called sliding mode control method. Some numerical simulations are also included to visualize the effectiveness and the feasibility of the developed approach.
RBF neural network based H∞ synchronization for unknown chaotic ...
Indian Academy of Sciences (India)
control (Bai & Lonngen 1997, Bai & Lonngren 2000), time-delay feedback approach (Park. 2005, Ahn 2010), backstepping design technique (Wu & Lu 2003, Hu et al 2005), complete synchronization (Zhan et al 2003), and so on, have been successfully applied to the chaos synchronization. In recent years, neural networks ...
Permanent synchronization of camcorders via LANC protocol
Vrancic, Damir; Smith, Steven L.
2006-02-01
A device, which keeps two camcorders permanently in synchronization, has been developed. The mentioned device uses LANC (CONTROL-L) camcorder's inputs for synchronization. It enables controlling of two camcorders simultaneously via built-in buttons, by using external LANC remote controller and/or by the PC via serial (RS232) communication. Since device requires LANC inputs on camcorders or ACC inputs on still cameras, it can be used on some camcorders produced by manufacturers Sony and Canon or some still cameras produced by Sony. The device initially synchronizes camcorders or still cameras by applying arbitrarily delayed power-up pulses on LANC (ACC) inputs. Then, on user demand, the camcorders can be permanently synchronized (valid only for some camcorders produced by Sony). The effectiveness of the proposed device is demonstrated by several experiments on three types of camcorders (DCR-TRV900E, HDR-HC1, HVR-Z1U) and one type of still camera (DSC-V1). The electronic schemes, PCB layouts, firmware and communication programs are freely available (under GPL licence).
A universal projective synchronization of general autonomous ...
Indian Academy of Sciences (India)
Fuzhong Nian et al and the validity of our method was verified through theoretical analysis and numerical simulations. 2. Generalized projective synchronization controller design. Consider a general autonomous system: ˙X = AX + B. (1). Here X = [x1, x1,..., xn]T is the state vector of the drive system, B is a n × 1 constant.
Modified function projective combination synchronization of ...
Indian Academy of Sciences (India)
Modified function projective synchronization between the newly constructed combination hyperchaotic Lorenz system and hyperchaotic Lu system is investigated using adaptive method. By Lyapunov stability theory, the adaptive control law and the parameter update law are derived to make the state of two systems as ...
Modified function projective synchronization of multistable systems ...
African Journals Online (AJOL)
The controllers are derived in such a way that the transformation matrix can be chosen arbitrarily to achieve a desired synchronization scheme. Numerical simulation results presented show the e?ectiveness of the proposed MFPS for transformation matrix with di?erent constant values and transformation matrix with time ...
Synchronization in multicell systems exhibiting dynamic plasticity
Indian Academy of Sciences (India)
cellular functions are controlled by combinations of positive and negative feedback processes [1]. The highly ... well-known examples of oscillators, which get synchronized due to coupling [13–15]. The exchange of .... uct, S3, through an allosteric enzyme, E, and negative feedback with end product inhibition of S1 by S3 ...
Hybrid synchronization of hyperchaotic Lu system
Indian Academy of Sciences (India)
For the hybrid synchronization, we define the state errors between the response system that is to be controlled and the ... When (7) is stabilized by the feedback v, the error will converge to zero as. Pramana – J. Phys., Vol. 73, No. ... For (8) to be asymptotically stable, the feedback system of the element of the matrix A must ...
DEFF Research Database (Denmark)
Pedersen, Dennis; Pedersen, Torben Bach
2004-01-01
. However, the XML data sources are often independent of the data consumers and may change their schemas without notification, invalidating the XML views defined by the data consumers. This requires the view definitions to be updated to reflect the new structure of the data sources, a process termed view......The increasing availability of XML-based data sources, e.g., for publishing data on the WWW, means that more and more applications (data consumers) rely on accessing and using XML data. Typically, the access is achieved by defining views over the XML data, and accessing data through these views...... synchronization. XPath is the most commonly used language for retrieving parts of XML documents, and is thus an important cornerstone for XML view definitions. This paper presents techniques for discovering schema changes in XML data sources and synchronizing XPath-based views to reflect these schema changes...
LHC synchronization test successful
The synchronization of the LHC's clockwise beam transfer system and the rest of CERN's accelerator chain was successfully achieved last weekend. Tests began on Friday 8 August when a single bunch of a few particles was taken down the transfer line from the SPS accelerator to the LHC. After a period of optimization, one bunch was kicked up from the transfer line into the LHC beam pipe and steered about 3 kilometres around the LHC itself on the first attempt. On Saturday, the test was repeated several times to optimize the transfer before the operations group handed the machine back for hardware commissioning to resume on Sunday. The anti-clockwise synchronization systems will be tested over the weekend of 22 August.Picture:http://lhc-injection-test.web.cern.ch/lhc-injection-test/