液压马达变负载恒速控制动态特性对比

Comparison of Dynamic Characteristics of Variable Load Constant Speed Control of Hydraulic Motor

对比分析了液压马达变负载恒速控制的3种形式:变转速电机控制、比例阀控制、比例泵控制。针对每种控制形式的控制方法和特点,分别建立了3种恒速控制形式的数学模型,并对其响应特性作出预测。通过实验得到3种控制形式的动态响应曲线,对比发现阀控系统超调量最大,响应时间最短;泵控系统超调量最小,响应时间最长;变转速电机响应特性处于两者之间。基于PID控制对3种恒速控制动态特性进行了对比,有助于液压马达在不同工况要求下选择不同的恒速控制模型。

Three forms of variable load constant speed control of hydraulic motor are compared and analyzed:variable speed motor control,proportional valve control and proportional pump control.According to the control methods and characteristics of each control form,the mathematical models of three constant speed control forms are established respectively,and their response characteristics are predicted.The dynamic response curves of three control forms are obtained through experiments.It is found that the overshoot of valve control system is the largest and the response time is the shortest;The pump control system has the smallest overshoot and the longest response time;The response characteristics of variable speed motor are between the two.This paper compares the dynamic characteristics of three constant speed control based on PID control,which is helpful to select different constant speed control models for hydraulic motor under different working conditions.