Machine analysis with unbalanced terminal constraints by d-q harmonic balance

A method of analysing AC machines subjected to unbalanced source impedances using a harmonic balance approach is set forth. The analysis assumes a constant rotor speed of any value with stator voltages that are arbitrary but periodic. This d-q harmonic-balance technique is applied to the problem of capacitor-start/capacitor-run single-phase permanent-magnet motor performance calculations. The results conclusively show the need for retaining at least one distortion term in addition to the fundamental frequency term.