直驱式伺服阀用四余度线性力马达磁力特性研究

Study on the Magnetic Characteristics of Four-Redundancy Linear Force Motor for Direct Drive Servo Valve

为明确某直驱式伺服阀用四余度线性力马达的磁力特性,在采用解析法建立线性力马达磁路模型的基础上,基于Maxwell对其在静磁场下的磁路分布、衔铁受力、正常/故障下的衔铁位移-力特性进行分析。正常/故障下衔铁位移-力特性的对比表明:正常工作时两种结构具有一致的静态特性,故障模式下径向布局结构各线圈故障对力马达静态特性的影响相同,而轴向布局结构对力马达静态特性的影响则与故障线圈的位置有关。此外还对其在瞬态场下的频率特性和线圈间的感生电动势进行分析,结果表明:轴向布局结构比径向布局结构的四余度线性力马达幅频特性更高。对四余度线性力马达的磁力特性进行了详细分析,为其进一步的设计改进提供了参考。

In order to clarify the magnetic characteristics of a four-redundancy linear force motor for a direct-drive servo valve,the magnetic circuit model of the linear force motor was established by analytical method,and its magnetic circuit distribution,armature stress and armature displacement-force characteristics under normal/fault conditions were analyzed based on Maxwell.The comparison of armature displacement-force characteristics under normal/fault conditions show that the two structures have the same static characteristics under normal operation;in fault mode,the influence of each coil fault on the static characteristics of the force motor is the same under radial layout structure,the influence of each coil fault on the static characteristics of the force motor is related to the position of the faulty coil under axial layout structure.In addition,the frequency characteristics under transient field and the induced electromotive force between coils were analyzed.The results show that the amplitude-frequency characteristics of the axial layout structure are higher than those of the radial layout structure.The magnetic characteristics of four-redundancy linear force motor are analyzed in detail,which provides guidance for its further design improvement.