Torque-to-weight ratio improvement with soft magnetic composite material in high speed switched reluctance motor

In aircraft electric motor drive fuel delivery system, the motor must be characterized by high power density, reliability, less size, less weight and high speed [1]. The high speed operation, fault tolerance, high power density makes switched reluctance motor an ideal candidate for high speed aerospace applications. This paper investigates the application potential of soft magnetic composite material (SOMALOY 500) characterized by three dimensional ferromagnetic behavior, very low eddy current loss, flexible machine design and assembly in high-speed switched reluctance motor. Two configurations (i) all sheet metal (ii) all Soft magnetic composite have been studied using finite element analysis to obtain their magnetic characteristics. The weight of active parts has been evaluated for the two configurations to determine torque-to-weight ratio. The study reveals that the all soft magnetic composite configuration albeit suffers from poor average torque, digress in torque-to-weight ratio from conventional model is not very much which makes it a viable alternative in high speed aerospace applications.