Back EMF Analysis of a Novel Linear Flux Switching Motor With Segmented Secondary

A novel linear flux switching motor (LFSM) with simple passive segmented secondary (SSLFSM) is presented in this paper. In this motor, the armature and field winding concentrated coils are wound around mover (primary) teeth alternatively. The structure of this linear motor is different from other types of LFSMs presented in previous research. All LFSMs are suffering from unbalanced back electromotive force (EMF) waveform. The same problem appears in SSLFSM. In this paper, the influence of secondary segments number on back EMF waveform of designed SSLFSM is derived analytically. It is found that the secondary segment numbers have a strong effect on generated back EMF waveform harmonic contents and phase balances. These effects are evaluated by finite-element analysis for different configurations of SSLFSM as well. With analytical and numerical evaluations, a suitable number of secondary segments for minimum harmonic contents and phase unbalances is obtained.