Electromagnetic Analysis of the V-Shaped Interior Permanent Magnet Motor at Constant Speed

Abstract

This study presents an electromagnetic evaluation of an interior permanent magnet (IPM) motor designed for hybrid electric vehicle (HEV) traction. The motor analyzed is a single-layer, V-shaped IPM configuration, comparable to the traction motor used in the Toyota Prius III. A two-dimensional finite element analysis (2D FEA) approach is introduced and applied to determine the motor’s electromagnetic performance under both no-load and rated-load conditions at constant speed. Under no-load operation, cogging torque and back electromotive force (EMF) are calculated. For rated-load operation at constant speed, the analysis computes electromagnetic torque, losses in the magnets and iron core, along with input electrical power and output mechanical power. The influence of the control angle on the electromagnetic torque is analyzed and control angle providing the maximum electromagnetic torque is determined. The periodicity of the cogging torque is established using an analytical method, and the optimal current control angle is identified to support control strategies for the IPM motor. The resulting electromagnetic characteristics are examined in depth to assess their influence on the efficiency and overall performance of the IPM motor in HEV traction systems.