科研之友
微信
新浪微博
Facebook
分享链接
摘要
Due to its high level of energy transformation, giant magnetostrictive material (GMM) has been used in hydraulic systems; however, the single-stage GMM-based servo valve is restricted to low flow rate applications. In this paper, we present a novel nozzle-flapper servo valve based on GMM. The design was introduced taking into account temperature compensation, pre-pressure exertion and magnetic driving circuit, then the theory basis for the servo valve was established, and by experimental study, we discussed the effects of parameters like the driving current, fixed orifice's diameter, oil supply pressure, null nozzle-flapper clearance and bias driving current on the control characteristics. Based on the experimental and simulation results, it is found that the GMM nozzle-flapper servo valve has achieved control characteristics of nonlinearity of 2%, pressure variation of 0.49 MPa, step response of 1 ms and amplitude(-) frequency response bandwidth (-3 dB) of 680 Hz, which prove that the GMM nozzle-flapper servo valve is suitable as pilot stage of multi-stage electrohydraulic servo valves for large flow rate applications.
