Research on Magnetic Stability and Improvement Method of a Novel Permanent Magnet Synchronous Servo Machine

The irreversible demagnetization of permanent magnet machines can lead to a decrease in electromagnetic performance, which in turn affects its reliability. This paper proposes a permanent magnet synchronous servo machine (PMSSM) with improved anti-demagnetization capability. Firstly, the finite element model (FEM) for partial PM demagnetization of a typical permanent magnet machine is established. Secondly, a method to improve the PM magnetic pole structure is proposed to enhance its anti-demagnetization. Then, the compensation method for demagnetization is provided after the magnetic performance of PMSSM deteriorates. Finally, the effectiveness and feasibility of the magnetic pole improvement and demagnetization compensation method are verified by the finite element analysis results.