Design aspects of 4:2 pole-2 phase switched reluctance motors

Switched reluctance motors (SRM) are nowadays a well established choice for rugged and reliable variable speed drive applications. The 4:2 pole-2 phase configuration is particularly suited for low cost drives due to simpler motor construction and simpler driver topology with only two power switches. This solution has been proposed for fractional horsepower and relatively high speed applications like hand tools and light domestic appliances. In this paper some design aspects are treated, concerned with the SRM magnetic circuit. An analytical approach is first utilized for main geometric parameters definition and torque evaluation. In the sequence, a numerical approach utilizing finite element method is carried out to precise torque and inductance characteristics determination.