Model of an Rotating Valve Based Electro-Hydraulic Servomechanism and its Dead-Zone Compensation Control

Abstract

This paper present the structure of the rotating valve based electro-hydraulic servomechanism and analyze its model. The electro-hydraulic servomechanism consists of the controller, the step motor, the rotating valve and cylinder, and the displacement sensor. In the servomechanisms model, it contains a time-varying dead-zone. To eliminate the dead-zone effect, we construct a dead-zone inverse model compensates the controller output. The parameters of the dead-zone inverse model are tuned on-line according to the dynamic performance of the feedback system by a group of rule functions. The controller employs the SIMENS PLC S7-200 and using STL program realizes control algorithm and the dead-zone inverse model. This simulative and practical experimenting results show that the compensation method is feasible.