Starting Characteristic Analysis of the V-Shaped Interior Permanent Magnet Motor

This research paper deals with the electromagnetic analysis of the V-shaped interior permanent magnet (IPM) motor for the hybrid electric vehicle (HEV). Like Toyota prius III traction motor, a V-typed single-layered IPM motor is investigated. A two-dimensional (2D) finite element analysis (FEA) methodology is discussed and adopted to compute the electromagnetic characteristics of the IPM motor, at no load conditions, with and without stator current excitation, and accelerating from starting to constant speed conditions. The cogging torque of the IPM motor at no load and zero stator current is calculated to ascertain the dynamic stability as well as instability positions of the motor that is of great essence in understanding the startup behavior and the overall performance of the motor. An existing control method modulates the stator supply current, depending on the position of the rotor of the IPM motor. This control approach is used to provide a fixed phase difference between the rotor and the stator magnetic fields so that the IPM motor can smoothly accelerate as it goes into the constant speed. The electromagnetic torque oscillates during the IPM motor's acceleration and despite of the fluctuations, the V-shaped IPM motor demonstrates the reliable performance, and accelerating and stabilizing at its target speed. The 2D FEA is utilized to investigate the IPM motor's dynamic behavior during the startup for its potential application in hybrid electric vehicle (HEV) traction systems.