Optimisation of PM-Assisted Synchronous Reluctance Motor with Rectangular Flux Barriers

This paper reports the optimisation of a 4-pole ferrite magnet-assisted Synchronous Reluctance Motor for a submersible water pump. The inverter-fed motor has rectangular flux barriers in its rotor, on which rectangular-shaped magnets are embedded. Each pole of the motor features three flux barriers, and a set of five variables for each flux barrier is used to describe the complete geometry of the rotor. These variables are subjected to a multi-objective optimisation process, which targets maximising the efficiency, maximising the power factor (for reducing the inverter size by maximizing the product of efficiency and power factor) and minimising torque ripple. The result of the optimisation study is presented, showing the improvement brought into the various performance figures of the motor.