Magnetic Equivalent Circuit for Surface-Mounted PM Motor

Electric machine design optimisation requires tools that provide reliable information about machine parameters. Magnetic equivalent circuit (MEC) technique is selected here for predicting machine performance. MEC is developed for a fractional slot, permanent magnet synchronous motor (PMSM). The model includes saturation, fringing effect in air gap and accounts for relative motion of the rotor. Even with saturation being incorporated, the adopted solution converges the model within few iterations. Performance quantities of the motor like flux density, induced EMF, flux linkage, inductance and cogging torque are evaluated. The results of MEC are validated with finite element analysis (FEA) and few with experiments.