Magnetically biased inductor for an aerospace switched reluctance drive

The development of actuators for the `more-electric´ aircraft is a major challenge. Switched reluctance machines offer some advantages over their permanent magnet counterparts for fault tolerant actuators, specifically the lack of drag torque during faults. High ripple current produced by these machines poses a challenge for designer of the drive system for use with aircraft DC power supplies. Magnetically biased inductors are useful in filter applications where there is a significant DC offset in the current. The utilization of a permanent magnet to partially offset the flux in the inductor core enables a reduction in inductor mass for a given device. Development of the concept beyond a traditional E-core towards a more space efficient Pot-core construction using soft magnetic composite materials is described. Finite element analysis of the inductor and experimental results are presented, along with examples to support the efficacy of the inductor within the aerospace actuator drive.