Mechanism Study Of Direct Driven Electro-hydraulic Servo Valve Based On GMM Actuator

It has become a hot topic at home and abroad that using new functional material to develop driving and controlling components with high performance in the field of fluid power transmission and control. As a new high-tech functional material, Giant Magnetostrictive Material has many excellent properties such as fast response speed, large magnetostrictive strain, and large output force, etc. So its applied basic research in fluid element has attracted people’s attention.In this paper, a new automatic thermal compensation GMM actuator for electro-hydraulic servo valve is presented on the basis of GMM, and its theoretical analysis is made. The static and dynamic mathematical models are established, and its AMESim simulation model is also established. The results show that the automatic thermal compensation GMM actuator has characteristics of fast response, large output displacement and large output force etc, its step rise time, output displacement and output force are respectively0.25ms,85.4μm and991N.Based on the above automatic thermal compensation GMM actuator, aiming to improve the response speed and bandwidth of direct driven servo valve, a new direct driven electro-hydraulic servo valve based on GMM actuator is presented. Thorough analysis and research of its general structure, mathematical models, internal flow passages, and various parameters etc is made by combining method of theoretical analysis, static and dynamic simulation analysis, finite element analysis and flow field simulation analysis, the main factors having effects on its performance are obtained, the influence law of its static and dynamic characteristics caused by the structural parameters is obtained, the distribution law of its internal flow field is also obtained. The results show that the static characteristics of GMM servo valve can be improved by chooseing overlap of valve port, radial clearance, and throttling-edged fillet radius etc reasonably. The dynamic characteristics of GMM servo valve can be improved by choosing oil supply pressure, radial clearance, equivalent mass, and equivalent damping coefficient etc reasonably. The output flow of GMM servo valve is6.02L/min under10MPa oil supply pressure, its step response rise time is0.7ms, steady adjusting time is1.2ms, bandwidth is765Hz.Compared with the traditional direct driven electro-hydraulic servo valve, it’s visible that direct driven electro-hydraulic servo valve based on GMM actuator has features of fast response speed, high bandwidth, large output flow, and better stability etc, which can meet the technical requirements of high frequency response, large flow, and strong antipollution ability etc, so it can be applied to aviation, aerospace, military industry and precise position control, etc.