A five-phase interior permanent magnet generator-diode rectifier with a non-integer number of stator slots per phase as the front end of a wind generation system

This paper presents the models of a five-phase interior permanent magnet machine (IPM) feeding a rectifier resistive load. The model predicts the performance of a machine with a non-integer number of stator slots per pole. Using the stationary and rotor reference frames, the approximate diode switching functions are derived. Then harmonic balance technique is used to obtain the steady state average and ripple models for the prediction of the system´s performance. The steady state model helps in determining the equivalent AC resistive load across the five-phase generator output capacitor bank. The obtained results reveal that despite the imbalance of the stator windings, the machine is still able to produce near balanced voltages at normal operation, and also the fraction of the rated output power with very little harmonic components in the output load voltage when a rectifier leg is open.