Development of grid-connected wind energy system employing interior PM Synchronous Generator and multi-pulse rectifier

In this paper, a novel grid integration system for a variable-speed wind turbine using Interior Permanent Magnet Synchronous Generator (IPMSG) is developed. The power-conditioner system (PCS) consists of a series-type 12-pulse diode rectifier powered by a phase shifting transformer and then cascaded to a PWM voltage source inverter. The series-type 12-pulse diode rectifier of the generator-side converter can work without any control, while the q-axis active current of the grid-side PWM inverter is only controlled to follow the optimized active current reference. The optimal active current reference is determined by using a simple MPPT algorithm which requires only three sensors in order to track the maximum power of the wind turbine. The losses in the IPMSG can be effectively reduced by setting a passive filter at the generator terminals. The laboratory results indicate that the proposed construction and scheme are simple, cheep and efficient.