Flux Weakening Control of an Open Winding Machine with Isolated Dual Inverters

This paper presents the flux weakening control method of an open winding machine which is connected to the two isolated inverters. The methods of the current reference modification and the over voltage modulation of two inverters are proposed to enhance the flux weakening control of the open winding machine at high speed. Furthermore, the power flows through two inverters are controlled independently as desired. The validity of the proposed flux weakening control method is verified by experiment results. The results show that the torque capability of the machine can be extended by 15% under the same current limitation compared to the Y-connected machine with the single inverter.