Yongpeng Zhang
Norwich University, Electrical and Computer Engineering, Faculty Member
- Lawrence Technological University, Electrical and Computer Engineering, Faculty Memberadd
The paper presents a methodology to make the load torque disturbance compensation based on the normal state observer. First, a state feedback controller is designed to achieve a satisfied speed command tracking performance. Then a... more
The paper presents a methodology to make the load torque disturbance compensation based on the normal state observer. First, a state feedback controller is designed to achieve a satisfied speed command tracking performance. Then a multi-purpose state observer is constructed to observe the motor states (current and speed), as well as to provide the disturbance compensation. Since the variable of load torque is beyond the motor system state space model, some observation error will be inevitably existed in the observed states. Based on the demonstrated mathematics derivation, the state observation error feedback can be isolated from the exact state feedback. Such a state observation error feedback actually constructs some kind of feedforward compensation for the load disturbance. If the observer gain is picked up appropriately, then the effect of the load torque variation can be considerably compensated, such that the system performance deviation will be greatly attenuated. Both MATLAB/Simulink simulation and dSPACE DSP-based implementation have confirmed its effectiveness in the permanent magnetic synchronous motor (PMSM) drive system.
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ABSTRACT This paper presents a robust proportional-integral-derivative (PID) controller design method for permanent magnetic DC (PMDC) motor. The PID controller parameters are systematically developed through the linear quadratic... more
ABSTRACT This paper presents a robust proportional-integral-derivative (PID) controller design method for permanent magnetic DC (PMDC) motor. The PID controller parameters are systematically developed through the linear quadratic regulator (LQR) approach, such that satisfactory performance with guaranteed closed-loop stability is achieved. In order to deal with modelling error and input saturation, an internal model control (IMC) structure is utilized, such that system robustness is improved, without the need for an observer. The proposed method is implemented through the dSPACE digital signal processor (DSP) system, and the experimental result confirms its effectiveness.
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ABSTRACT Our technological demands today require extremely challenging control solutions such as real-time applications of Networked Control System (NCS). However, due to communication protocol and shared data bus, NCS always experiences... more
ABSTRACT Our technological demands today require extremely challenging control solutions such as real-time applications of Networked Control System (NCS). However, due to communication protocol and shared data bus, NCS always experiences uncertain and unpredictable time delays in both input and output channels. These delays cause asynchronization between controller and plant thereby degrading the performance of closed-loop control systems. To address the concern of stability improvement in real-time, this paper proposes to utilize digital redesign technique to compensate for these network induced delays.
Research Interests: Computer Networks, Digital Control, Stability, Sensors, Actuators, and 12 moreReal Time Systems, Time Delay, Closed Loop Control, Real Time, Real Time Application, Delays, Networked Control System (NCS), Pulse Width Modulation, Communication Protocol, Performance Index, Delay Compensation, and Synchronisation
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Network controlled system will always experience some delays in communications, and how to improve its stability is of great importance for industry applications. In this paper, one novel method of delay compensation by utilizing digital... more
Network controlled system will always experience some delays in communications, and how to improve its stability is of great importance for industry applications. In this paper, one novel method of delay compensation by utilizing digital redesign is proposed. First, analog controller is designed for the delay free system, and then the delay compensation algorithm is modulated through A/D conversion. In
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ABSTRACT This paper proposes a discretization scheme and an optimal digital cascaded plus state-feedback controller for Multiple-Input-Multiple-Output (MIMO) continuous-time systems with multiple time delays in both inputs and outputs.... more
ABSTRACT This paper proposes a discretization scheme and an optimal digital cascaded plus state-feedback controller for Multiple-Input-Multiple-Output (MIMO) continuous-time systems with multiple time delays in both inputs and outputs. Firstly, an equivalent discrete-time model is obtained from the MIMO analog time-delayed system. The equivalent discrete-time model and a partially predetermined digital cascaded controller are formulated as an augmented discrete-time state-space system for state-feed forward and state-feedback Linear Quadratic Regulator (LQR) design. As a result, the parameters of the cascaded controller and its associated state-feedback controller can be determined by tuning the weighting matrices in the LQR optimal design. Then a discrete-time optimal observer for the MIMO analog time-delayed system is constructed for the implementation of the designed state-feedback digital controller. The proposed methodology has been verified through both simulation and experiment on the induction motor drive system.
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ABSTRACT The modeling and minimal realization techniques for a specific multiple time-delay continuous-time transfer function matrix with a delay-free denominator and a multiple (integer/fractional) time-delay numerator matrix have been... more
ABSTRACT The modeling and minimal realization techniques for a specific multiple time-delay continuous-time transfer function matrix with a delay-free denominator and a multiple (integer/fractional) time-delay numerator matrix have been developed in the literature. However, this is not the case for a general multiple time-delay continuous-time transfer function matrix with multiple (integer/fractional) time delays in both the denominator and the numerator matrix. This paper presents a new approximated modeling and minimal realization technique for the general multiple time-delay transfer function matrices. According to the proposed technique, an approximated discrete-time state-space model and its corresponding discrete-time transfer function matrix are first determined, by utilizing the balanced realization and model reduction methods with the sampled unit-step response data of the afore-mentioned multiple time-delay (known/unknown) continuous-time systems. Then, the modified Z-transform method is applied to the obtained discrete-time transfer function matrix to find an equivalent specific multiple time-delay continuous-time transfer function matrix with multiple time delays in only the inputs and outputs, for which the existing control and design methodologies and minimal realization techniques can be effectively applied. Illustrative examples are given to demonstrate the effectiveness of the proposed method.
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This paper presents a new optimal sliding mode controller using the scalar sign function method. A smooth, continuous-time scalar sign function is used to replace the discontinuous switching function in the design of a sliding mode... more
This paper presents a new optimal sliding mode controller using the scalar sign function method. A smooth, continuous-time scalar sign function is used to replace the discontinuous switching function in the design of a sliding mode controller. The proposed sliding mode controller is designed using an optimal Linear Quadratic Regulator (LQR) approach. The sliding surface of the system is designed using stable eigenvectors and the scalar sign function. Controller simulations are compared with another existing optimal sliding mode controller. To test the effectiveness of the proposed controller, the controller is implemented on an aluminum beam with piezoceramic sensor and actuator for vibration control. This paper includes the control design and stability analysis of the new optimal sliding mode controller, followed by simulation and experimental results. The simulation and experimental results show that the proposed approach is very effective.
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Today's technological demands require challenging control solutions such as real-time applications of Networked Control System (NCS). However, due to communication protocol... more
Today's technological demands require challenging control solutions such as real-time applications of Networked Control System (NCS). However, due to communication protocol and shared data bus, NCS experiences uncertain and unpredictable time delays in both input and output channels. These delays cause asynchronization between the controller and the plant thereby degrading the performance of closed-loop control systems. To address this problem, this paper proposes to utilize digital redesign technique to provide real-time random delay compensation.
Research Interests: Forecasting, Distributed System, Digital Control, Computer Simulation, Industry, and 15 moreComputer Systems, Manufacturing Engineering, Real Time Systems, Feedback, Closed Loop Control, Real Time, Online Systems, Real Time Application, ISA Transactions, Computer communication networks, Communication Protocol, Equipment Design, Analog to Digital Conversion, Electrical And Electronic Engineering, and Delay Compensation
In this article, we address the optimal digital design methodology for multiple time-delay transfer function matrices with multiple input–output time delays. In our approach, the multiple time-delay analogue transfer function matrix with... more
In this article, we address the optimal digital design methodology for multiple time-delay transfer function matrices with multiple input–output time delays. In our approach, the multiple time-delay analogue transfer function matrix with multiple input–output time delays is minimally realised using a continuous-time state-space model. For deriving an explicit form of the optimal digital controller, the realised continuous-time multiple input–output time-delay system is discretised, and an extended high-order discrete-time state-space model is constructed for discrete-time LQR design. To derive a low-order optimal digital observer for the multiple input–output time-delay system, the multiple time-delay state obtained from the multiple time-delay outputs is discretised. Then, the well-known duality concept is employed to design an optimal digital observer using the low-order discretised multiple input time-delay system together with the newly discretised multiple time-delay state. The proposed approach is restricted to multiple time-delay systems where multiple time delays arise only in the input and output, and not in the state.
Research Interests: Engineering, System Identification, Optimal Control, Systems Science, Modeling, and 15 moreDigital Control, Optimization, Digital design, Mathematical Sciences, digital PID controller, Time Delay, Space Time, Transfer Function, Matrix Multiplication, Observer, Input Output, Observer Design, Continuous time, Discrete time, and State Space Model
Research Interests: Engineering, Optimal Control, Systems Science, Modeling, Self Control, and 15 moreNeural Networks, Neural Network, Kalman Filter, Mathematical Sciences, Control Design, State Space, Dynamical System, Linear Quadratic regulator, Dynamic System, Discrete Time Systems, State Feedback Control, Non Linear Control, Covariance, Innovation, and Discrete time
In the models of piezoelectric actuator (PEA) systems, the hysteresis effects are often described by the concise Bouc–Wen models; however, these models are nonlinear and non-smooth because of the existence of terms which involve the... more
In the models of piezoelectric actuator (PEA) systems, the hysteresis effects are often described by the concise Bouc–Wen models; however, these models are nonlinear and non-smooth because of the existence of terms which involve the absolute-value function. In particular, a challenging control problem is posed when, due to the properties of certain materials, such absolute-value terms are of high order. This control problem has been rarely studied. This article proposes the use of the approximated scalar sign function (ASSF), which is a numerically stable and differentiable nonlinear function, to represent the hysteresis function, with single-order or high-order absolute-value terms. This innovative step leads to a nonlinear but sufficiently smooth model. Then, a systematic digital design methodology is presented, which involves the following steps: (1) establish an optimal linear model based upon the resulting smooth model, (2) adopt a PI-based analogue controller and (3) apply the prediction-based digital redesign technique for digital implementation. A digital observer is also developed for state reconstruction, and to improve the input disturbance rejection. The positioning control of a PEA system with a high-order hysteretic Bouc–Wen model is implemented to demonstrate the effectiveness of the proposed ASSF based modelling and controller design approaches.
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Page 1. IMA Journal of Mathematical Control and Information (2004) 21, 433456 Digital PID controller design for multivariable analogue systems with computational input-delay YONGPENG ZHANG, LEANG-SAN SHIEH AND ...
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ABSTRACT A minimal realisation scheme for a class of multiple time-delay transfer function matrices with distinct poles is presented. Also, a simple minimal realisation method is developed for a specific two-input-two-output multiple... more
ABSTRACT A minimal realisation scheme for a class of multiple time-delay transfer function matrices with distinct poles is presented. Also, a simple minimal realisation method is developed for a specific two-input-two-output multiple time-delay system whose poles can be repeated. In addition, a state-space discretisation technique developed for a multivariable system with a single time delay is extended to a multivariable system with multiple time delays. Finally, it should be mentioned that the proposed approach is restricted to systems where multiple time delays arise only in the input and output, and not in the state. Illustrative examples are given to demonstrate the effectiveness of the proposed method.
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Research Interests: Engineering, Communication systems, Robust control, Controller Design, Digital Signal Processors, and 14 moreDspace, Industrial electronics, Robust stability, Observer, Tuning, Digital Signal Processor, Communications Technology, Linear Quadratic regulator, Speed Control, Switches, Disturbance rejection, Proportional Control, Permanent Magnet Synchronous Motor, and permanent magnet
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Through the conventional Jacobian linearization, its operation has to be limited in the neighborhood of equilibrium. To address the control requirement in off-equilibrium region, optimal linearization is introduced to describe the exact... more
Through the conventional Jacobian linearization, its operation has to be limited in the neighborhood of equilibrium. To address the control requirement in off-equilibrium region, optimal linearization is introduced to describe the exact dynamics at any operating point with minimal approximation error. In the illustrative example of Rotary Inverted Pendulum, a universal dynamic nonlinear model is firstly developed. Then its local linearized model is updated by every sampling period to match with the current operating point. Meanwhile, its controller is also updated to correspond with the updated local model. Thus, swing-up control and balance control can be both implemented through a unified Linear Quadratic Regulator controller, which can effectively avoid control law switching in the two stages.