Magnetic Field Analysis of a Novel Permanent Magnetic Suspension Pole Shoe Based Bearing Less Switched Reluctance Motor Using Finite Element Method

For high speed control of Bearing Less Switched Reluctance Motor (BSRM), the torque and radial force has to be decoupled. A novel Permanent magnet pole shoe type based suspension poles is proposed for a 12/14 BSRM, to decouple suspension force and radial torque and also radial forces generated in x and y-axis. A pole shoe type permanent magnet made of Neodymium Magnet, which is an alloy of Neodymium, iron and boron material (NDEFB) is placed on the all four suspension poles. The selection of pole shoe is taken according to force required to levitate the rotor mass in air gap. The width and arc are taken without disturbing the self starting phenomena of rotor. When the motor is excited, the flux distribution in the air gap under phase A is short flux path and there is no flux reversal in the stator core. This will decrease saturation effect and the MMF required producing motoring torque which decreases core losses. The decoupling of radial force and motoring torque are achieved and the decoupling of radial force in positive and negative x and y directions is achieved. The performance of the proposed motor is compared with 12/14 conventional BSRM model and the results are presented and analysed.