Comparative Study of Three-Phase PWM Rectifiers for Wind Energy Conversion

摘要

This paper presents a study of alternative PWM rectifier topologies that can meet power conditioning requirements of induction as well as permanent-magnet synchronous generators for wind energy conversion. The studied topologies use three bidirectional switches in combination with a three-phase diode bridge, and are previously used only for unity power factor rectification. These topologies can also operate with either leading or lagging input power factor, hence can be used to supply reactive power to induction and permanent-magnet synchronous generators while extracting active power from them. The topologies are compared to the conventional six-switch PWM voltage-sourced converter (VSC) in terms of switching and conduction losses. Additionally, the common-mode voltage generated by these topologies under different modulation methods is analyzed and shown to be significantly lower than that generated by the conventional six-switch VSC. Simulation results of the alternative topologies operating with an induction generator are presented and start-up issues and maximum and minimum rotor speed limits are also addressed.