Acoustic noise mitigation for high pole count switched reluctance machines through skewing method with multiphysics FEA simulations

This study investigates the effect of different skewing methods and angles for switched reluctance machines (SRM) having high pole count using multiphysics simulations. A 24/16 SRM is modeled for each skewing method and different skewing angles using 3D electromagnetic finite element analysis (FEA). Mechanical and acoustical analyses are performed to evaluate the effectiveness of different skewing methods. The results for each method are compared for the same torque levels. For Stator-only and Rotor-only skewing methods, torque output drops significantly, which reduces the effectiveness of these methods in achieving desired torque levels. However, implementing skewing on both the stator and rotor together has less impact on the torque production and has a significant impact on distributing the radial force on the stator back iron. Given an SRM designed to achieve 150kW of output power, multiphysics simulations predict a 10.5 dBA reduction in the acoustic noise for an optimized rotor/stator skewing angle of 13.5°.