Magnetic Field Analysis and Performance Optimization of Double-Rotor Interior Permanent Magnet Synchronous Motor

The double rotor interior permanent magnet synchronous motor (DR-IPMSM) serves as a critical component in electric vehicle energy conversion systems. Its multi-source magnetic potential configuration and intricate magnetic circuit topology introduce challenges including complicated magnetic field distributions and difficult performance optimization processes. These complexities further contribute to the limitations of conventional analysis methods, manifesting as excessive computational demands and compromised accuracy. To address these limitations, the paper proposes an enhanced analytical method for DR-IPMSM. The method accounts for complex pole geometries and magnetic bridge saturation effects. Through area equivalence principles, the permanent magnet (PM) subdomain is treated with multi-segment equivalence. The Magnetic Equivalent Circuit model and iterative method are combined to consider the saturation effects of the magnetic bridge. Using this method, the magnetic field of a new DR-IPMSM is analyzed, and then combined with the Maxwell stress tensor method, the critical parameters are identified. Setting these parameters as design variables, the DR-IPMSM performance is multi-objective optimized. The prototype is fabricated and tested. The results show that the output performance is improved because the optimized DR-IPMSM significantly reduces the air-gap flux density distortion rate, cogging torque, and torque ripple. This work provides a theoretical reference for magnetic field analysis and performance optimization of the DR-IPMSM.