Different control schemes for current source converters in wind applications

Different current source converter topologies for wind turbine applications are presented and analyzed in the paper. In high-power and medium-voltage range, current source converter has its natural advantages, such as simple topology, compact size, high power capability, excellent short circuit protection, and flexible power flow control. However, it also presents some challenges for control scheme development. In the paper three different approaches are shown. One utilizes phase control thyristors and active filter for harmonics compensation, while other uses PWM controlled SGCTs. Finally, the third solution presents direct torque control and virtual-flux based direct power control (DPTC). Simulation results are given for all presented control schemes and some features of each control are emphasized.