Analysis of the induced EMF in permanent magnet brushless motors

The performance of permanent magnet brushless DC motors depends on their winding and magnetic designs. The conductor distribution and flux density distribution profiles determine the shape of induced EMF waveform. The shape of the induced EMF of the machine can be used to predict its torque performance. This paper presents a new method to analyze the induced EMF of the permanent magnet brushless motors including the effect of fringing and leakage flux. The Fourier harmonic method is used to analyze the induced EMF. The induced EMF is constructed in time using the harmonics for few typical machine designs.