SINGLE-PHASE MOTOR INDUCTION-RUN PERFORMANCE

ABSTRACT

Based on the rotating-field theory and the ‘exact’ equivalent circuit of a single-phase induction motor operating on its main winding only, accurate solutions are derived for the salient features of its torque to speed performance at pull-out and zero torque, to enable the torque-speed plot to be readily compiled with sufficient accuracy for preliminary-design purposes. The torque, current, power factor and efficiency at any speed are also derived for use in the final-design stage, again on the assumption that the airgap mmf is sinusoidally distributed. However, in order to be strictly applicable to many modern designs, the analysis is extended to cover in a simple manner the general case of significant space-harmonic mmfs being present in the airgap.