A Quantitative Analysis of Grouped Single-Phased Induction Motors

A quantitative evaluation of the effect of single-phasing on three-phase induction motors has eluded engineers with an interest or responsibility in this problem area. Although the classical analysis for such an evaluation based on symmetrical components has been generally known, the complex nature of the problem solution did not become feasible until computer programs were developed. The results of a computer-aided study are presented. Quantitative data related to motor voltage and current as well as stator and rotor heat losses-as influenced by system stiffness and motor mechanical loading-are offered in graphical format. The data included are limited to grouped induction motors whose single-phasing is due to the blowing of a fuse in the primary of a delta-wye-connected supply transformer.