连续旋转液压伺服关节性能分析

Performance of continuously rotating hydraulic servo joint

为解决现有液压伺服关节不能实现连续旋转的问题,探讨一种利用转阀式伺服阀控制双作用叶片马达的转角方案。通过将马达的输出轴与阀套固联,将输出轴上的转角直接作为反馈信号,控制输出轴转角对阀芯输入的跟随。根据马达进油腔和回油腔容积周期变化规律推导出其在一个周期内容积变化的数学表达式并绘制相应的曲线。在此基础上,建立系统动力学模型并进行PID校正,由仿真结果得出校正后关节的调节时间为0.036s,跟随误差为0.018mrad,在外负载为80N·m时的稳态误差为1.25mrad,表明该关节动态响应快、跟随性准确且抗干扰性能强。

In order to solve the problem of the hydraulic servo joint that cannot rotate continuously,this paper discusses a double cell vane motor whose continuous rotation angle is controlled by the rotary servo valve.The output shaft of the motor is connected fixedly with the valve sleeve,and the angle of the output shaft is used directly as the feedback signal to control the rotation angle of the output shaft so as to follow the spool input.According to the variation of volume in inlet chamber and return chamber of the motor in a cycle,the mathematical expression of the variation of volume is deduced and the corresponding curves are drawn.On this basis,the system dynamic model is established and compensation with PID is carried out.The simulation shows that the adjusting time of the joint is0.036 s,and the transient state error is 0.018 mrad after PID correction.The steady state error is only 1.25 mrad when the external load is 80N·m.The results demonstrate that the joint dynamic response is fast and accurate,and the joint has good performance in anti-interference.