Power Hardware-in-the-Loop based Emulation of an Open-Winding Permanent Magnet Machine

Open-winding permanent magnet (PM) motors are increasingly being used in electric drive systems due to several advantages over traditional PM motors such as a wider speed range of operation, and improved fault tolerance. Novel testing techniques such as power hardware-in-the loop (PHIL) based machine emulation can be used to expedite the testing of new motor topologies such as the open-winding PM motor. This paper investigates the emulation of an open-winding PM machine. In order to control or suppress lower order harmonics resulting due to the emulated machine back-emf, current controllers are proposed in this paper. These proposed controllers, used for the driving inverter and the machine emulator, use multiple resonant controllers in combination with proportional-integral (PI) controllers to achieve control over emulated current harmonics of interest. Experimental results are presented to validate the performance of the proposed current controller and also highlight the utility of the developed machine emulator system to emulate various operating conditions of the open-winding PM machine.