Comparison of three phase rectifier topologies in small wind turbines

Small wind turbines are used for local energy production or in island networks. They are usually installed at places, where the wind speed is relatively low and considerable fluctuation occurs, resulting in a challenge to offer a high energy production especially at low and gusty wind speeds. For these conditions an optimal drive train has to be selected. In this paper the focus is on typical rectifier topologies applied to small wind turbines as a part of the drive train. Therefore, five rectifier topologies are analyzed and compared concerning relevant comparison factors: DC link voltage and current, the losses (efficiency) based on a virtual power semiconductor, the costs, the volume, the performance of the machine side currents and power vs. generator speed characteristics. The aim is to show with a help of a ranking method, which topology is the best due to the decided criteria.