A Computationally Efficient Finite-Element/Analytical Model for Simulating Electric Machines with Rotor Movement

A new approach for simulating electric machines by combining the finite element method with an analytical model of the air gap is presented. Although the initial setup of the model makes the approach more computationally intensive than traditional finite element analysis (FEA) for the simulation of a single rotor position, the simulation of subsequent rotor positions is dramatically faster than traditional FEA. As such, the approach is suitable for use in simulating electric machines as part of a larger dynamic simulation, such as that of an electric vehicle. The approach exploits the fact that only certain spatial harmonics of the magnetic field exist in the air gap of conventional machine designs to improve computational performance. Simulation results validate the accuracy and speed of the proposed method.