Nonlinear system active disturbance rejection control method based on interference observer

Abstract

The invention relates to a nonlinear system active disturbance rejection control method based on an interference observer, targeting a nonlinear single-input and single-output system containing an unknown nonlinear function and harmonic wave interference. The nonlinear system active disturbance rejection control method based on an interference observer comprises steps of performing mathematic representation on the harmonic wave interference and the nonlinear function, establishing an external model of the harmonic wave interference, designing an interference observer and an extended state observer on the basis of control input and measurement output information, completing estimation on the harmonic wave interference, the unknown non-linear function and a system state, designing an active disturbance controller according to the output of the interference observer and the extended state observer and completing gain solving of the observer and the controller on the basis of a separation theorem and a pole arrangement theory. The nonlinear system active disturbance rejection control method based on the interference observer has advantages of high interference resistance and high control accuracy and can be used for high accuracy control containing the interference and the unknown non-linear system.

Description

Technical field [0001] The invention relates to an active disturbance rejection control method for a nonlinear system based on an interference observer, which can realize simultaneous estimation and cancellation of harmonic interference and unknown nonlinear function, and can be used in system control containing harmonic interference and unknown nonlinear function . Background technique [0002] Complex control systems, especially nonlinear systems, are often affected by a variety of uncertain dynamics such as model uncertainty and unknown nonlinearity, which severely restrict the improvement of control performance. Control strategies, including modern control theories such as optimal control and robust control, are designed based on the ideal model of the system, often considering only one or one type of interference, ignoring many unknown nonlinear factors, and are more conservative . For example, LQG control considers a system affected by a single Gaussian white noise, and w...

AI Technical Summary

Problems solved by technology

[0004] The technical problem of the present invention is: aiming at the problems that the existing control method relies too much on the system model, the control precision is low, and it is difficult to compensate the harmonic interference and the unknown nonlinear function at the same time, it provides a method with harmonic interference and unknown Active disturbance rejection control based on disturbance observer based on nonlinear function real-time estimation and offset capability, the present invention has the advantages of strong anti-disturbance ability and high control precision, and can be used for high-precision control of disturbance-containing and unknown nonlinear systems

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