Rotor Saliency Ratio Analysis of Interior Permanent Magnet Synchronous Machines Considering Variable Leakage Flux Property

By designing an intentional leakage bridge between magnet poles in interior permanent magnet (IPM) machines, a variable leakage flux property according to the load current can be obtained. Due to the coupling characteristic of magnetic circuit in inter-polar leakage bridge, the most suitable saliency ratio for variable leakage flux property is unclear. In this paper, four machines with different magnetic barriers were constructed by rotor saliency ratio design principles. Through finite element and experimental studies, it is achieved that the positive low saliency ratio is the best choice for variable leakage flux machine design. It provides a guidance for the future design of this type of machine.