电液位置伺服系统的频域设限加权切换控制

摘要

分析电液位置伺服系统二阶状态反馈(DOSF)控制系统存在静差的机理,设计三阶无静差状态反馈(TOSF)控制器.为克服TOSF控制系统阶次高的缺陷,以切换频域设限加权算法实现TOSF-DOSF双控制器切换控制,切换频域设限减小了控制作用量对加权系数变化的灵敏度.仿真结果表明:电液位置伺服DOSF控制系统静差与负载弹性刚度正相关,TOSF控制系统能消除系统静差且符合动态性能设定.测试实验结果表明:TOSF-DOSF双控制器频域设限加权切换控制使系统具有良好的动静态性能,与阈值切换相比,具有较小的切换冲击.%The mechanism of the double-order state feedback (DOSF)control system that had static errors was analyzed.A three-order state feedback (TOSF)controller without static errors was designed.To overcome the high order of TOSF control systems,a finite frequency domain weighting switching algorithm was adopted to realize TOSF-DOSF dual-controller switching control.The algo-rithm might reduce the sensitivity of control action on weighting coefficient changing.Simulations show that the static errors of electro-hydraulic position servo DOSF control system are positive corre-lation with load elastic stiffnesses and TOSF control system may eliminate static errors in conformity with dynamic performances.Experiments show that the system with TOSF-DOSF dual-controller fi-nite frequency domain weighting switching control has good dynamic and static performances.It has smaller switching impacts compared with threshold switching.