Investigation on open-winding PMSG system fed by three level NPC converter and diode converter

In medium and high voltage application, NPC topology has been widely investigated concerning the modulation strategies and control methods. Meanwhile, the open winding configuration is gaining the increasing attention in large power drive field. The semi-controlled open winding PMSG system with the integration of three-level full controlled voltage source converter (VSC) and uncontrolled diode converter will be investigated in this paper. The proposed semi-controlled open winding PMSG system has less switch losses, simpler system configuration and still inherits the advantage of traditional open-winding configuration such as the multilevel modulation effect. Based on the mathematical model of the semi-controlled open winding PMSG system, the control scheme is proposed, which is based on the vector control with rotor flux orientation. Finally, a simulation is built to validate the theoretical investigation on the open winding PMSG system.