三泵控直驱液压系统动态特性及复合控制方法

Dynamic Characteristics and Compound Control of Tirple-pump Direct Driven Hydraulics

为解决双泵控直驱液压系统中非对称缸低压侧压力过低导致稳定性差的问题,提出了一种三泵控直驱液压闭式系统及带有位置预测补偿的速度/位置复合控制方法。介绍了双泵控非对称缸系统和三泵控非对称缸系统两种系统的工作原理,分析了其动态特性,建立液压系统各元件数学模型,而后在MATLAB/Simulink中建模仿真,探讨负载、速度大小及方向改变对系统动态特性的影响。结果表明,该三泵控非对称缸系统较双泵系统具有更好的动态特性;所提出的复合控制方法与PID位置控制方法相比,能更加快速稳定地到达目标位置。

In order to address the stability problem of dual-pump direct driven hydraulics,caused by the insufficient pressure at the lower pressure side of the asymmetric cylinder,a velocity-position compound control method with MPC(Model Predictive Control)for a triple-pump controlled asymmetric cylinder is proposed.The comparison of dynamic characteristics between the dual-pump system and triple pump system is performed.Further,the effects of varying load and speed on system characteristics are analyzed based on the simulation in MATLAB/Simulink.The results show that the proposed triple-pump controlled asymmetric cylinder has better dynamic performance than the double-pump system under varying load and speed.Compared with the PID(Proportion Integration Differentiation)position control,the proposed control method can reach the desired position quicker and stabler.