泵控液压系统中马达转速稳定控制及仿真分析

泵控液压马达系统中，由于外负载突变会导致发动机转速变化，进而引起变量泵转速改变，最终造成液压马达转速波动量过大及调整时间过长。针对变量泵-定量马达闭式液压系统，构建数学模型，得到传递函数框图，分析负载变化导致马达转速波动的原因。提出一种前馈补偿控制方法，通过实时改变变量泵的斜盘摆角来补偿变量泵转速扰动而引起的流量变化。推导补偿函数，并分别对阶跃100%负载、阶跃20%负载工况及斜坡100%负载、斜坡20%负载工况进行仿真。结果表明：增加前馈补偿控制后，马达转速波动量最大减少了3.87%,调整时间最多缩短了1.77 s。

Stability Control and Simulation of Motor Speed in Pump-Control-Motor Hydraulic System

In the pump-control-motor hydraulic system,due to the sudden change of external load,the engine speed will change,which will lead to the change of the variable pump speed,and eventually the hydraulic motor speed fluctuation is too large and the adjustment time is too long.Aiming at the closed hydraulic system of variable pump and fixed motor,the mathematical model was constructed in detail,the block diagram of transfer function was obtained,and the reasons for the fluctuation of motor speed due to load change were analyzed.A feedforward compensation control method was proposed,which could compensate the flow change caused by the speed disturbance of the variable pump by changing the swash plate swing angle of the variable pump in real time.The compensation function was deduced,and the simulation analysis was carried out for step 100% load,step 20% load condition and ramp 100% load,ramp 20% load condition.The results show that the motor speed fluctuation with feedforward compensation control is reduced by 3.87% at most,and the adjustment time is shortened by at most 1.77 s.