Active Disturbance Rejection Control Of Automatic Voltage Regulator System

Automatic voltage regulator(AVR)is a kind of electrical equipment,also known as automatic excitation regulator,which is the core part of the excitation system control,used to stabilize and adjust the output voltage of the generator.AVR automatically adjusts the excitation current by monitoring the generator output voltage and load changes to keep the generator output voltage stable at the set value.In this paper,the following researches are carried out around the controller design of the automatic voltage regulation system:1)Firstly,the order of the existing AVR system model is reduced,and the order of the fourth-order system is reduced to the first-order inertial system with delay,and then the PID controller and the second-order active disturbance rejection controller are tuned by using the known methods.The simulation results show that the second-order LADRC controller obtained by this method has similar robustness to the PID controller,and the second-order LADRC controller has better tracking performance than the PID controller,but its distrubance rejection performance can be improved.2)After analyzing the third-order LADRC,it is found that it is essentially a linear combination of proportionality,differential,second-order differential,and integral(PIDD),so it is considered to design a third-order LADRC to improve system disturbance rejection performance and response speed.Compared with the PIDD controller,the third-order active disturbance rejection controller has better control performance.In order to better apply ADRC technology,aiming at the practical problem of stator current limitation,the structure of ADRC is modified,and the difference between ideal generator output and actual generator output is introduced into ESO for fast compensation.It can successfully improve the control performance of the system and achieve more precise and stable control.3)In order to further optimize the parameters of the ADRC,a tree species optimization algorithm is introduced.The algorithm can take into account both the global optimal solution and the local optimal solution.The results show that the parameters of the ADRC obtained by this algorithm can effectively improve the control performance of the ADRC,and can ensure appropriate robustness while taking into account the distrubance rejection performance.