Comparison of FSPM topologies applied in open-winding wind power system

Open-winding permanent magnet (PM) generator power system is an important research direction of wind power. Compared with rotor-PM motor, flux-switching permanent magnet (FSPM) machines have the advantage that is suitable for flux-weakening operation and has no risk of PM demagnetization. Hence, FSPM machine is applied to the open-winding power system in this paper and six topologies of FSPM machines are selected. With the aid of 2D finite element analysis, the electromagnetic torque, PM flux and self-inductances are investigated and compared with emphasis on the torque-speed characteristics. Furthermore, the new flux-weakening equation of open-winding FSPM wind power system is derived for the first time in this paper and the similarities and differences with the electromotor mathematical model is also revealed. The correctness of the equation is verified by simulation.