先导式大流量电液比例方向阀优化匹配研究

摘要

The control and structure design of a high capacity, electro hydraulic pilot proportional direction valve were studied, and a matching method for the dead zone nonlinear compensation and the optimization design of structure parameters was proposed based on the consideration that unreasonable control algorithms and structure designs for the valve can reduce its matching performance thus its position control performance is lowered. The mathematical model of the unmatched valve was established. The stability criterion of the valve was reached by using the describing function method, and the compensation circuit was used to compensate the dead zone to realize the match of the proportional controlling amplifier and the valve. Taking the superior position control performance as the target of optimization, a genetic algorithm was used to design the structure parameters of the throttling groove of the pilot valve, so the match of the pilot valve and the main valve was realized. A co simulation model for the valve was established based on AMESim and Simulink. The simulation results showed that the optimization and matching not only kept the stability of the system but also optimized the position control performance of the valve, and the method was verified to be feasible and have a certain reference value in the design of the valve.%针对先导式大流量电液比例方向阀因控制算法和结构设计不合理造成其匹配性能较差，从而导致其位置控制性能较差的问题，进行了控制算法和结构设计研究，提出了死区非线性环节补偿和结构参数优化的匹配方法。建立了对称非匹配先导阀控主阀的数学模型，利用描述函数法得到了该阀的稳定性判断条件，并设计了定值补偿电路补偿死区，实现了比例控制放大器与比例阀的匹配；以位置控制性能优良为寻优目标，利用遗传算法对先导阀节流槽结构参数进行优化设计，实现了先导级与主级的匹配。建立了基于AMESim和Simulink的比例阀机电液联合仿真模型，仿真证明，死区补偿及结构参数优化设计在保证系统稳定性的同时能够有效提高阀的位置控制性能，验证了优化匹配方法的可行性，对比例阀的设计具有一定的参考价值。