磁流体对双喷嘴挡板伺服阀工作性能的影响

Influence of magnetic fluids on working performance of twin flapper-nozzle servo valve

通过分析伺服阀的工作原理及力矩马达工作间隙中磁流体的作用机理,运用键合图理论以规范的方式统一描述系统中的机液能量耦合、流体磁化以及电磁转换等多种能量作用;考虑磁流体作用力等非线性因素,采用集中参数建立电液伺服阀的通用仿真数学模型,模拟添加磁流体前后及力矩马达工作气隙参数变化对伺服阀工作性能的影响规律,通过试验证明该模型的有效性。研究结果表明:添加磁流体可增加伺服阀力矩马达的阻尼比,提高系统的稳定性和抗干扰能力;增大工作气隙高度或减小导磁体有效工作面积均有利于提高系统的稳定性,但降低了系统的流量增益。

By analyzing the working principle of servo valve and the mechanism of the magnetic fluids filled into the working gaps of a torque motor, the bond graph method was introduced to describe the energy input, transfer, translation and dissipation of the system, and the lump parameters model of the system was developed in a unified way, in which the magnetic resistance and other nonlinear factors were taken into consideration. The system state equations were derived from the model. The effects of magnetic fluids and the working air gap parameters on the dynamic characteristics of servo-valve were studied by numerical simulation, and the model was verified experimentally. The results show that the magnetic fluid can be used to increase the torque motor damping ratio to improve the system stability. Increasing the height of air gap and reducing the working area of magnetizer can improve the system＇s stability, but reduce the flow gain of the system.