Development of a magnetostrictive material–based electro-hydrostatic actuator with an active rotary rectifying valve

Abstract

A magnetostrictive material–based electro-hydrostatic actuator with an active rotary valve for fluid rectification is presented in this article, which consists of a magnetostrictive material–based pump, an active rotary valve and a hydraulic cylinder. First, the magnetostrictive material–based pump plunger motion model is established, and the factors that affect the phase lag between the magnetostrictive material–based pump plunger displacement and the input voltage are discussed. Second, the flow area model of the active rotary valve and the kinetic model of the cylinder are established. After that, the phase compensation for the input voltage that influences the synchronous motion between the magnetostrictive material–based pump plunger and the valve spool is investigated. Finally, the simulation model is built in MATLAB/Simulink, and the results are subsequently verified with experimental data. The results indicate that the phase lag of magnetostrictive material–based pump plunger output displacement is mostly influenced by magnetization with a low driving frequency and by an eddy current with a high driving frequency. The compensation angle for the input voltage affects the output flow of the magnetostrictive material–based electro-hydrostatic actuator and the moving direction of the cylinder piston rod. For a magnetostrictive material–based electro-hydrostatic actuator rectified by the active rotary valve, at the driving frequency of 200 Hz, the peak output flow can reach 2.4 L/min, which is much higher than 1.1 L/min of a magnetostrictive material–based electro-hydrostatic actuator rectified by the passive reed valve.