Sensitivity analysis to the design parameters of a hysteresis motor

Hysteresis motors are mainly used for some applications that need very smooth torque from starting to synchronous speed such as gyroscope and gas centrifuge. This paper presents a sensitivity analysis of 60 W, 400 V, 6000 rpm super-high speed hysteresis motor characteristics including electromagnetic torque, power factor, efficiency and stator current to the design parameters including mechanical, electrical and magnetic parameters. Simulations are carried out based on the steady-state equivalent circuit of a circumferential-flux type hysteresis motor. Results show some design parameters such as Br improve all mentioned motor characteristics. Whereas, other parameters such as decreasing Ns improve some characteristics (increases power factor) and impair the others (increases current). Moreover, it is shown that there is an optimum point for selection the volume of hysteresis ring to develop maximum torque.