Design And Control Of Electro-hydraulic Servo Active Suspension Road Simulation System

This article is based on the National Key R&D Program “Key Technology Research and Application Demonstration for High-Mobility Multi-Functional Emergency Rescue Vehicles”(2016YFC0802900).This paper analyzes the key technologies of active suspension road simulation test,and studies the acquisition and replication of road uneven signal when the vehicle is traveling,which lays the foundation for improving vehicle ride comfort and handling stability.According to the vehicle suspension conditions and technical indicators,the mechanical structure and hydraulic system of the suspension road simulator are designed.Design working device and perform finite element analysis on the cylinder using ansys to determine the structural parameters of the cylinder.Design hydraulic system according to system working pressure and mechanical structure,and select hydraulic components by calculating hydraulic system parameters.To analyze the dynamic characteristics of the system,a mathematical model of the test bench was established and a three-state control strategy with position,velocity,and acceleration was proposed.Using Simulink simulation to verify the three-state control can effectively expand the closed-loop system bandwidth,improve the dynamic characteristics of the electro-hydraulic position control system.In order to obtain road unevenness incentive information,an improved filtered white noise method is proposed to construct a controlled target signal.Using the Welch method to estimate the power spectrum of the collected road surface irregularity signal to obtain the spectrum signal.The Fourier transform of the spectrum signal is used to generate the white noise random wave.The filter is designed based on the pulse invariant method and the white noise signal is digitally filtered to obtain the target spectrum sequence.This signal is used as the input signal to establish a road simulation test system.In order to achieve road surface uneven excitation reproduction,a time waveform replication control strategy based on frequency response function identification and drive signal iteration is proposed.The results of the waveform replication test based on the rapid control prototype design show that the time domain error of the waveform reproduction is reduced and the correlation coefficient is increased.The signal replication accuracy of the test bench has been significantly improved.