Modeling of interior permanent magnet synchronous motors in the six-step conduction mode

This paper deals with the analytical description of an interior permanent magnet synchronous motor running in six-step conduction mode. It assumes a non-sinusoidal back emf, but inductances vary sinusoidally with the rotor position. The proposed model renounces Park's transformation and delivers a set of equations which allow the numerical simulation of phase currents and torque in the abc reference frame. This model reveals the influence of the phase advance angle on the characteristics of current flow. By means of the simulation model two control strategies are shown - maximum torque per amp control and flux weakening.