基于变结构与PID联合控制策略的车身高度控制仿真

对采用油气主动悬架的车辆车身高度进行控制时，由于摩擦力的影响，采用常规ＰＩＤ等传统控制策略系统存在振荡现象。为解决这个问题，通过分析悬架位移误差的相轨迹图，对ＰＩＤ控制的积分项系数进行切换控制，从而设计出了一种变结构与ＰＩＤ联合控制策略。仿真结果表明，与传统ＰＩＤ控制策略相比，此控制策略在消除系统振荡、获得较高控制精度等方面具有较好的控制性能。

Simulation of variable structure control strategy in combination with PID for vehicle body height

To control the body height of vehicle with active hydropneumatic suspension system, this paper presented a new control strategy to eliminate the oscillation arising from friction force and occurring in conventional PID control. This new control strategy is based on a variable structure control and PID control. Through analyzing the phase locus plot of the vehicle body height control error, a switch method of the coefficient of the integration part of PID control was designed. Accordingly, the new control strategy named variable structure combined with PID control was developed. The simulation results demonstrate this combined control strategy can achieve better control effects on vehicle body height than conventional PID control.