A Rotary-Linear SPM Voice Coil Motor With PM Flux Bridges for Output Performance Improvement

Abstract

This paper proposes a rotary-linear surface-mounted permanent magnet (PM) voice coil motor (RL-SVCM) with PM flux bridges in place of the iron flux bridges in a traditional RL-SVCM for enhancing average torque and force ripple but slight damage of torque ripple and average linear force. The iron flux bridges in a basic RL-SVCM cannot participate in the generation of rotary torque. In contrast, the PM flux bridges in the proposed RL-SVCM can participate in the generation of rotary torque. The magnetic equivalent circuit (MEC) is used to analyze the magnetic circuits of the basic and proposed models. The results explain the reasons for the performance improvements achieved by the proposed motor. The finite element method (FEM) is used to derive the precise output performance of the basic and proposed motors. Additionally, a prototype of the proposed RL-SVCM with PM flux bridges was manufactured for experimental verification. Close agreement between the experimental results and FEM results validates the feasibility of the proposed RL-SVCM.