Research On Design Method Of Active Disturbance Rejection Controller For Electric Load Simulator

Electric load simulator is the key equipment for semi-physical simulation performance test of vehicle steering system on the ground.This paper proposes to introduce the auto-disturbance rejection control technology into the load simulator control system.The greatest advantage of the ADRC is that it does not depend on the exact model of the system.It estimates the “total disturbance” and compensates by the extended state observer?ESO?,thus ensuring good anti-interference performance.First,the parameter determination method of the extended state observer,the most core part of the ADRC,is studied.By deducing the transfer relationship between the expanded state and the total disturbance to be observed,compare its equivalence with the performance of the low-pass filter.Then the Chebyshev lowpass filter is selected to complete the parameter design of the linear extended state observer,and the specific tuning steps and the optimization design process are given.Next,by deriving the sufficient conditions for the a symptotic stability of the nonlinear extended state observer,it is verified that this parameter design method is also applicable to nonlinear observation systems.Then,the effect of the ADRC control channel gain is analyzed and its parameter identification method is studied.By only taking the uncertainty of control gain as the disturbance value of the system,the closed-loop transfer function of the designed ADRC system is derived.Then according to the Rolls stability criterion,the value range of b₀ for stability of the closed-loop system is given.By analyzing the variation of the amplitude-frequency characteristics of the closed-loop system with different values of b₀,it is determined that its value should be as close as possible to the true value.Finally,a recursive empirical frequency-domain optimal parameter estimation method is selected to complete the identification.Finally,the design of the auto-disturbance disturbance control system for the electric load simulator is completed.The controller parameters are determined using the method studied in this paper,and the simulation results of the key performance indicators are given.