Abstract:The bearingless switched reluctance motor (BSRM) is a complex system with some characteri stics such as multi-controlling parameters, nonlinearity and high coupling. In order to improve its performance of suspension and motion, there are two difficulties: the decoupled control of torque and suspending force, and the accurate chopping control of its levitated currents in the high-speed operation. Based on the principles of the decoupled control, the paper classifies the existing BSRMs meeting decoupled control of torque and suspending force. And then the principles and characteristics of these existing BSRMs are expounded. Being different from these existing BSRMs, the paper presents four types of novel BSRMs, such as the double-salient-stator BSRM, the wider-rotor-pole BSRM, the hybrid-structure BSRM and the conical-structure BSRM, which can realize decoupling control of torque and suspending force. And there are some new topologies that may be developed from each type of these structures. In order to meet their self-coupling characteristics, the working modes for these BSRMs are created, then their decoupling principles are analyzed briefly. Finally, the FEA simulation results verify the validity of these BSRMs.