Key Technology Research Of Direct-acting High-frepuency Micro Servo Valve Based On GMM

Giant Magnetostrietive Material (GMM) is a new type of functional material. Its excellent performance as giant strain and large output force. It can respond quickly when the signal input. It has become a hot spot of research in the field of physics, materials science, electromagnetics, control engineering and mechanical engineering, the value of its application has been gradually revealed.In this paper, based on the merits of GMM, the structure of a new Giant Magnetostrictive Actuator(GMA), used in servo valve is designed, as well as its static and dynamic theory analysis worked. The mathmatical models are built for simulation analysis, the results of which show that the step rise timeTr and the steady state output force F of GMA are respectively0.8ms and1832N. This means GMA has notable features of high response and large output force. And based on the merits of GMA, a new structure of high-frequency direct-acting hydraulic servo valve is designed. Through theoretical analysis and computation, mathematical modeling and dynamic simulation analysis, electromagnetic finite element analysis, carried out a systematic study of its key technologies.Reached the following conclusions:For GMM direct-acting high-frequency servo valve, the phase margin γ=84°,gain margin Kg=17dB, amplitude wide ωb=499Hz, the amplitude across the frequency=403Hz, the phase crossover frequency=5780Hz. It is visible that GMM direct-acting high-freqency servo valve has features of fast response speed, high precision and better stability.The coil turns and damping of GMA convert and body structure of valve have a greater impact on the dynamic characteristics of the servo valve. Increasing the GMA damping can improve the high frequency characteristics of the servo valve. Increaseing the coil turns can increase the flow of the servo valve. Reducing the number of components of the servo valve can improve the response speed of the servo valve.This study Provides a theoretical basis for the design of direct-acting high-frequency servo valve based on GMM and injects new vitality to the studying of direct-acting high-frequency servo valve and provides an important basis for further optimization of the structure of the servo valve.