Study Of Diphase Oppositing GMM Self-sensing Actuator And Application In Water Hydraulic Servo Control Valve

Traditional electro-hydraulic servo valve driven by electromagnetism moment motor, with complex structure, large volume and narrow frequency width, small energy density, low resolution, poor anti-interference ability, is still unable to meet the needs of fluid control system in modern industry, so its application is limited greatly. GMM (Giant Magnetostrictive Material) is a new type of function martial appearing in recent years with giant strain, fast response speed, high energy density and large output force and so on. Based on the excellent performance of GMM, especially self-sensing characteristic, a new kind of diphase oppositing giant magnetostrictive self-sensing actuator is put forward, replacing traditional actuator, will realize closed-loop control and collated control, which can be able to improve response speed, control precision, reliability and to decrease cost of servo valve. In the thesis, the diphase oppositing giant magnetostrictive self-sensing actuator and application in water hydraulic servo control valve is systematically, deep analyzed and researched by combining theory analysis, computer simulation and experimental study together.The statics and dynamics analysis of the displacements amplifier, based on flexure hinges, was carried on by analytic method and ANSYS FE method, the enlargement factor, rigidity, resonance frequency and vibration model are calculated, the linear relationship between displacement loss and load force is established, and the veracity of FE method is verified. In addition, test system of diphase oppositing giant magnetostrictive self-sensing actuator is established, which error source and main influence factors are analyzed, statics characteristics and hysteretic characteristics of diphase oppositing giant magnetostrictive self-sensing actuator have been studied experimentally.The equivalent dynamic model of diphase oppositing giant magnetostrictive self-sensing actuator is put forward, based on the Jiles-Atherton physics model, quadratic moment domain rotation model and structural dynamics principle, the dynamic model with hysteresis nonlinearity for servo valve is founded, namely dynamic coupling mathematical model of driving coil current→magnetic field intensity→magnetic domain motion→magnetostriction→output strain and displacement→spool displacement, and its statics and dynamics characteristics are simulated and analyzed by Matlab/Simulink. According to the problem of hysteresis nonlinearity, based on established inverse hysteresis model, feed-forward compensator is designed, at the same time, theory and method based on inverse hysteresis model and PID feedback control are put forward, thus realized effective compensation for hysteresis nonlinear characteristics of servo control valve.Through the research on electromechanical coupling mechanism and self-sensing mechanism of diphase oppositing giant magnetostrictive self-sensing actuator, electromechanical coupling model and real-time decoupling model based on...