Development and experimental characterization of a Multiple Isolated Flux Path reluctance machine

This paper presents an unconventional type of doubly-salient reluctance machine with Multiple Isolated Flux Paths (MIFPs) that has reduced eddy current and hysteresis losses and several other advantages that improve the power and/or torque density over that of comparably sized conventional reluctance machines. The design also offers the potential to reduce torque ripple and acoustic noise emission. A custom simulator was developed to carry out FEA-based geometric optimization and a second nonlinear parametric simulator was developed to conduct control optimization with consideration of impacts from mutual coupling between phases. Although design constraints were based upon vehicle propulsion applications, the machine is scalable and is well-suited for a wide range of applications. Using machine dimensions similar to that of the 2nd generation Toyota Prius, the projected performance of the machine indicates that the MIFP reluctance machine is capable of producing over 50 kW with less than 5% torque ripple using ripple mitigation techniques. In addition to simulation results, this paper also includes experimental results of the MIFP machine on a dynamometer at up to 23.4 kW.