Prediction of torque and inductance displacement characteristics of asymmetrically slotted variable-reluctance motors using a simplified model for numerical field solution

For prediction of static and dynamic performance of doubly-salient motors, it is essential to know their flux linkage-position-excitation characterist ics and also the static torque characteristics. At the design stage determi nation of these characteristics presents difficulties because of highly non linear behavior of the magnetic circuit. It is possible to use numerical fi eld solution of the complete motor to obtain this information. This, howeve r, requires expertise on a professional program and may be expensive if use d to search for the best design. This paper shows that a reduced model can be used to obtain the desired information accurately. It is also shown that in fact obtaining field solutions just for a pair of teeth is enough for a ccurately predicting the flux linkage and torque characteristics of a motor . The approach introduced here makes possible searching for an optimum desi gn (even on a PC) for maximizing average torque or reducing noise and vibra tion problems, since the effort for producing the model and computation tim e are greatly reduced.