Research On Control Strategy Of Electro-hydraulic Servo Active Suspension For Three-axis Vehicle

In the process of disaster relief,emergency rescue vehicles often need to travel on complex and poor roads,so emergency rescue vehicles need to have high ride comfort on complex roads.By installing an active suspension system on an emergency rescue vehicle,the purpose of improving the ride comfort of the vehicle can be achieved.The control strategy of the active suspension system largely affects the performance of the active suspension system,so it is necessary to study it.This paper combines the national key research and development plan "high-mobility emergency rescue vehicles(including fire-fighting vehicles)dedicated chassis and suspension key technology research"(2016YFC0802902)to study the control strategy of the three-axle emergency rescue vehicle active suspension system.Introducing the doubleloop control idea of the suspension system,the outer ring controller is designed to calculate the target output of the actuator according to the state of the vehicle body to eliminate the influence of road disturbance on the vehicle body;the inner ring controller is designed to control the active suspension electro-hydraulic servo The actuator quickly and accurately outputs the target power to improve the performance of the suspension system.The content of this article can be summarized as follows:(1)Established road and vehicle models.The random road surface excitation model is deduced and the performance evaluation index of the vehicle suspension system is given.According to the suspension system performance evaluation index and ride comfort requirements,the three-axis vehicle model is simplified,and the three-axis 9-degree-offreedom vehicle dynamics is derived.Model,establish the state space model of the vehicle main and passive suspension system.(2)The Kalman filter-based model predictive controller is designed as the outer loop controller of the suspension system.The Kalman filter is designed to optimize the vehicle state for the vehicle model.The suspension system model predictive controller(MPC)is designed according to the model predictive control theory.The active suspension model predictive controller based on Kalman filter is constructed.(3)A linear auto disturbance rejection controller is designed as the inner loop controller of the suspension system.A nonlinear model of the electro-hydraulic servo active suspension actuator was established.The linear auto disturbance rejection controller(LADRC)was designed to control the suspension actuator so that the suspension actuator can output the target accurately and quickly.Improve the performance of the suspension system.(4)Simulation and analysis of the inner and outer ring controllers respectively,LADRC-controlled suspension actuators can output power accurately and quickly,with fast response and good tracking performance;compared to passive suspension With the active suspension controlled by LQR,the active suspension of MPC control can effectively improve the ride comfort and steering stability of the vehicle,and can effectively avoid the suspension stroke saturation.