Power Factor Enhancement with Variable Flux Memory Motor for Heating, Ventilation, and Air Conditioning Applications

This study proposes a ferrite-based variable flux memory motor (VFMM) that predominantly produces reluctance torque rather than magnet torque. By adjusting the magnetization state (MS) of the permanent magnets (PMs), the design shifts its optimal power factor and efficiency regions across different speeds, enabling a broader operational range. An analytical framework is developed to outline the conditions required for achieving a unity power factor. Finite Element Analysis (FEA) results validate the improvements in power factor, increased efficiency, and extended operational limits. A comparative analysis demonstrates the VFMM's superior performance over its constant flux counterpart in the compression and blower modes in heating, ventilation, and air conditioning (HVAC) systems.