A NPC IGBT based medium voltage inverter applied to salient pole wound rotor synchronous machine

This paper presents the results of an implemented control strategy applied to an IGBT based Medium Voltage inverter with NPC topology driving a salient-pole synchronous AC machine. Tests with a 1000 HP synchronous machine and a three level inverter (4.16 KV / 120 A) were performed. The control system provides a high dynamic performance with a fast torque control. The additional functionalities necessary to drive a synchronous AC machine are depicted. The results also show the behavior of a synchronous bypass transfer of the machine from the inverter to the line supply.