Finite element analysis of flux-reversal machine considering BEMF current of a switch-off phase and v-i characteristics of a transistor and a freewheeling diode

This paper describes the effect of pulsating current generated by back-electromotive force (BEMF) current of switch-off phase in flux-reversal machine (FRM) which is driven by 120/spl deg/ square wave voltage sources. A two-dimension time-stepped voltage source finite element analysis using a direct convergence method is proposed to analyze an electromagnetic field and the BEMF current. To prove the propriety of the proposed analysis method, we build the prototype FRM and a digital signal processor (DSP) installed controller as a set for the experiment.