A Low-Cost Rectifier Topology for Variable-Speed High-Power PMSG Wind Turbines

A novel rectifier topology consisting of two three-phase diode bridges and three thyristors is proposed in the paper for variable-speed high-power permanent-magnet synchronous generator (PMSG) wind energy conversion systems (WECSs). The proposed rectifier has several prominent features such as low cost, low power loss, and simple control. Its ability to cascade the input voltages allows it to properly regulate generator speed even when the wind velocity drops to half of the rated value. Consequently, maximum power-point-tracking algorithms can be applied to optimize power capture in a wide range of wind velocities. The operating principle of the rectifier is elaborated. Its use and control in the WECS is presented. The converter and control are verified by simulation and experimental results.