基于PWM的开关阀控电液位置伺服系统负载特性仿真研究

Simulation Research on Load Characteristic of PWM On-off Valve Controlled Electro-hydraulic Position Servo System

针对开关阀控电液位置伺服系统在负载条件下上行和下行运动特性不一致,对液压回路中平衡阀模块加以改进,使得平衡阀两端压差不受负载变化影响,从而使液压缸上下行运动特性保持一致。通过分别研究空载和加载条件下系统静、动态性能,对系统进行AMESim仿真分析和优化,以提升系统运动过程平稳性。研究结果表明,结构优化后的系统动态响应速度快、跟随响应误差小、控制精度高,且加载后液压缸运动特性仍能保持一致,有效地提高了系统性能,为下一步系统样机研制奠定基础。

For the upward and downward movement characteristics are inconsistent, when PWM on-off valve controlled electro-hydraulic position servo system is under changing load condition, then the balancing valve module has been improved in the hydraulic circuit, which lead the pressure differential at two ends of the balancing valve will not he affected by the changing load, thus ensure the cylinder＇s upward and downward movement characteris- tics be consistent. In order to improve the motion stationarity of the system, static and dynamic performance in no- load and load of the system is researched. Moreover, the system is simulated and optimized by AMESim. The re- sults show that, after optimizing the structure , the system has a fast dynamic response, small tracking error, high control precision. In addition, the movement characteristics of the hydraulic cylinder remain consistent after load- ing, thus the characteristic of system has been improved effectively and laying the foundation for the further research of the system prototype.