Robust Control Design Procedure and Simulation of PRES Controller having Phase-Locked Loop(PLL) control technique in Grid-Tied Converter

A robust control design of a three blade, horizontal axis variable speed wind turbine is developed in this paper. The variable speed wind turbine model consists of higher order nonlinear dynamics where uncertainty has been considered in the plant parameters. Quantitative feedback theory is an effective and efficient, robust control technique through which the desired specifications over a specified range of parametric uncertainty can easily be achieved in the frequency domain. The proposed robust torque and pitch control in variable speed wind turbine using quantitative feedback theory satisfy prescribed gain and phase margin, degree of tracking for the robust performance, fast convergence, noise attenuation, and input and output disturbance rejection. The advantages of the proposed robust control design are the consideration of a wide range of performance specifications and achieving effective control over an increased operating frequency range. The simulation results demonstrate the satisfactory performance of proposed quantitative feedback theory-based controller and prefilter which fulfill the necessary conditions such as robust stability and robust tracking. Further, it has been shown that the performance of the quantitative feedback theory-based controller is better than the performance with a standard wind turbine controller and also from the performance by proportional-integral controller.

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Robust Control Design for an Uncertain Macroeconomic Dynamical System with Unknown Characteristics and Inequality Control Constraint

Complexity ◽

10.1155/2021/8826480 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Xiaorui Xie ◽

Ye-Hwa Chen

Keyword(s):

Dynamical System ◽

Robust Control ◽

Design Procedure ◽

Control Design ◽

Uniform Boundedness ◽

Salient Feature ◽

Uncertain System ◽

Stabilization Policy ◽

Bounded Controls ◽

Robust Control Design

The stabilization problem of a macroeconomic dynamical system is considered in this paper. The main features of this system are that the system uncertainties may be unknown functions of state and time but with known bounds. Furthermore, the control inputs are subject to constraints, which is a salient feature in an economic control problem. To ensure that the controls are within the specified boundaries, in our control design procedure, a creative diffeomorphism, which converts bounded controls into unbounded corresponding signals by choosing an appropriate transformation function, is proposed. For the uncertain system, a deterministic robust control is designed to render the practical stability: uniform boundedness and uniform ultimate boundedness. The range of the input bounds is related to the uncertainties and can be designed according to the actual situation. Numerical simulations are performed to verify the effectiveness of the stabilization policy.

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Identification, uncertainty modeling and robust controller design for an electromechanical actuator

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406215616141 ◽

2016 ◽

Vol 230 (20) ◽

pp. 3631-3641 ◽

Cited By ~ 1

Author(s):

Rafik Salloum ◽

Mohammad Reza Arvan ◽

Bijan Moaveni

Keyword(s):

Robust Control ◽

Controller Design ◽

Low Cost ◽

Design Procedure ◽

Control Design ◽

Uncertainty Modeling ◽

Feedback Compensation ◽

Robust Control Design ◽

High Dynamics ◽

Low Sensitivity

Electromechanical actuators (EMAs) are of interest for applications which require easy control and high dynamics. This paper addresses the experimental identification, structured and unstructured uncertainties modeling, and robust control design for an EMA system with harmonic drive. Two robust controllers are designed by two proposed approaches: The first is based on Kharitonov theorem, which not only robustly stabilizes the uncertain EMA system but also maintains the pre-specified margins and bandwidth constraints. The second is feedback compensation design procedure based on H∞ control theory, verifying good tradeoff between the powerful H∞ controller and the unique features of feedback compensation, such as simplicity, effectiveness, low sensitivity to parameters variations, low cost, and easy implementation. Simulation and experiments prove the robustness and high tracking performance of the robust EMA systems which reveals the affectivity of the proposed robust control design methods.

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