Simplified Calculation of Radial Force Spectrum in SRM for Acoustic Noise Prediction in Preliminary Machine Design

An analytical method for prediction of the radial force spectrum in switched reluctance machines is presented. The radial force waveform is approximated with a tetragon shape and the resulting spectrum is derived analytically. The characteristic points of the tetragon may be determined analytically, by simple lumped parameter simulation models or finite element analysis (FEA).