A low-cost wind generator system with a permanent magnet synchronous generator and diode rectifiers

Abstract

A low-cost wind generator system for small-or medium-scale wind generator is proposed. The system consists of a permanent magnet synchronous generator (PMSG) with two sets of the three-phase stator windings, i.e. six-phase stator winding, two three-phase diode rectifiers, a boost chopper, and a three-phase pulse-width modulation (PWM) inverter. Since two sets of three-phase stator windings are spatially shifted by 30 electrical degrees, the system can cancel out the dominant harmonic magnetomotive forces (MMF) produced by the harmonic currents of diode rectifiers. The simulation and experimental results show that the proposed system can significantly reduce the pulsation of the developed torque and the DC current by more than 60 % in comparison with the conventional system consisting of a three-phase PMSG and a three-phase diode rectifier. Therefore, the proposed system can use a smaller smoothing reactor in the boost chopper, so that the lower initial cost can be realized, and it is suitable for small-or medium-scale wind generator systems.