Impact of continuous conduction on the constant power speed range of the switched reluctance motor

It is shown that in the absence of speed sensitive losses the constant power speed range (CPSR) of the switched reluctance motor (SRM) is infinite when continuous conduction is allowed during high speed operation. Therefore, the SRM is a candidate motor for all traction applications including those involving heavy vehicles which may require a CPSR of 10:1 or greater. Analytic expressions are derived relating average and rms motor current and average motor power to the design parameters of the motor. The analysis is based on a linear magnetics model that neglects saturation. Generally, magnetic saturation has a pronounced impact on the performance characteristics of an SRM and linear analysis yields inaccurate results; however, it is shown that a linear model is highly accurate in predicting high speed performance when the SRM operates in continuous conduction. The analytic results may provide useful guidance for tailoring the design of SRMs for high CPSR applications