非零开口的阀控非对称缸系统不变性补偿控制

Compensation control of a non-zero open valve controlled asymmetric cylinder system based on model invariance

针对比例控非对称缸正反方向运动响应不一致的问题,建立了非零开口的阀控非对称缸系统的线性负载流量模型,根据数学模型分析了系统的负载流量特性,定义了非对称系统的基本状态,并将其设为非对称系统的不变结构.提出了融合负载、结构、非对称叠合量等影响因素的不变性补偿控制方法,将系统的任意非对称状态通过不变性补偿控制等价于基本状态,使得非对称系统得到对称的负载流量特性.实验结果表明:通过不变性补偿控制,比例阀控非对称缸系统在阀线性区域,非对称系统负载压力不超过泵压的1/2时,负载流量与基本状态时的负载流量误差不超过11%;非对称系统在基于不变性补偿的基础上,采用统一的比例-积分-微分(PID)控制器,使得正反向运动响应能达到基本一致.

For the problem of the inconsistent dynamic property,the linear load flow model of the valve controlling asymmetric cylinder system was developed,including the influence of the non-zero open.Base on the model,the load flow property was analyzed and the basic state of the asymmetric system,which is set to the same structure,was defined.Besides,the control method based on the structure invariance was proposed considering the structure and load effect,and any asymmetric state of the system was equivalent to the basic state through compensation,and then the symmetrical load flow property was obtained.The experimental results show that the error of load flow in servo valve controlled asymmetric cylinder system is less than 11%compared with the basic state,in linear region of the servo valve and 1/2of pump pressure of the load.Unified PID（proportion-integration-differentiation）controller can be used in the asymmetric system on the basis of invariant compensation control,and the movements in forward and reverse direction achieve almost the same response.