Magnetic Model Identification of Multi-Three-Phase Synchronous Motors

Multi-three-phase motor drives are experiencing a significant development among the multiphase solutions since they are configured as multiple three-phase units operating in parallel. Although the literature reports several torque controllers able to deal with multi-three-phase motors, most of them obtain high performance of torque regulation as long as flux and torque maps of the machine are known. The literature currently reports very few contributions dealing with the experimental identification of flux and torque maps of multi-three-phase synchronous motors operating in healthy and open-three-phase fault conditions. In addition, almost all these research contributions focus on dual-three-phase machines. This paper thus proposes an experimental test procedure to directly identify the flux and torque maps of a multi-three-phase synchronous motor featuring an arbitrary number of three-phase winding sets. The proposed identification procedure also allows an accurate machine analysis considering all potential open-three-phase fault scenarios. Experimental results obtained on a 12-phase interior permanent magnet synchronous motor using a quadruple-three-phase configuration of the stator winding are presented. Besides, flux and torque maps obtained in severe open-three-phase fault conditions are shown, fully validating the proposed identification procedure.