Abstract
The synchronous reluctance motors operated by a PWM inverter can be designed for the maximum saliency ratio (Ld/Lq). The saliency ratio is the most important parameter for achieving a high torque capability, high power factor and wide constant-power speed range. Generally, flux guides for the d-axis and flux barriers for the q-axis are provided to achieve a high Ld and low Lq, respectively, in order to maximize the saliency ratio. In this paper, the optimal shape and thickness of the flux barriers are investigated analytically. It is also demonstrated that the optimal rotor flux barrier shape can be expressed as the contour line of the function that shows the magnetic potential in a uniform material rotor. The effects of the magnetic resistance of the stator and the gap are also analyzed.
