Coupled Electromagnetic Field Computation with External Circuit for the Evaluation the Performance of Electric Motor Designs

In this paper, a set of PM machine's designs, having the similar level of nominal input and outputs i.e. voltage, torque, and speed were compared to evaluate the effectiveness of a computational design procedure. The designs include the machines with distributed winding arrangements, different number of slots, different pole widths, and different slot opening shapes. The physical characteristics of machines such as the cogging torque, back emf, flux linkages, and inductances were calculated from a 2D nonlinear transient finite element analysis with motion. The torque and speed profiles of all of the machines were calculated from the phase variable modeling approach. The phase variable model is a database representation of the machine's numerical model and it allows computationally efficient dynamic simulation of the coupled problem with realistic physics-based design. The phase variable models of the machines were linked to the driving circuit to determine the mutual effect of machine design parameter and the drive topology on the performance measures of machines.