Comparative Analysis in Single-Phase Induction Motors: Analytical, Numerical, and Load Tests

Abstract

Single-phase induction machines have two windings in the stator to produce a rotating field: a main winding and an auxiliary winding. The stator slot leakage inductance varies with the position of the coils within the slot. The closer the winding is to the stator yoke, the greater the leakage flux and, consequently, the closer the winding is to the air gap, the lower the leakage flux. Based on this fact, the positions of the main and auxiliary windings within the slots were reversed in order to reduce the leakage flux. It was found that after the change in positioning, there was a 2.25% reduction in leakage inductance at start-up and a 2.02% reduction in leakage inductance in steady state (with only the main winding energized). It was also found that there was an increase in mechanical torque of 0.97% and an increase of 0.8% in mechanical power. To validate this study, computer simulations were performed using FEA in 2D and 3D to analyze the flux densities in the rotor and stator cores, as well as in the machine’s air gap. A 0.37 kW, 127 V, 4-pole prototype was prepared and tested for two winding arrangements.