Electromagnetic Performance Analysis of Hybrid Excited Segmental Rotor Flux Switching Machine

Due to the special rotor configuration, the coil flux linkage of permanent magnet (PM) excited segmental rotor flux switching machine (SRFSM) can be considered as the sum of the flux linkages produced by each of the adjacent PMs. Then, the hybrid excited SRFSM is obtained by replacing one PM in every pole pair by field winding to obtain high magnetic field regulation capacity. The configuration and operational principles are first discussed. To reduce the computation time, the analytical model of hybrid excited SRFSM with the subdomain method is developed. The electromagnetic performances such as the flux linkage, back electromotive force, electromagnetic torque, and eddy current loss in PM and rotor support are investigated using the analytical model. Furthermore, the effect of machine parameters on the torque ripple and average torque, and the effect of field current density on the flux weakening capability are also analyzed. The analytical results are verified by the finite-element method and prototype machine experiments.