Part One Building a 3HP Electronic Phase Converter

摘要

Several techniques are used to operate three-phase motors from a single-phase line. The traditional techniques include: the use of a static phase converter, which uses capacitors to accomplish phase shifts of the single-phase line voltage to approximate a three-phase waveform; the use of a rotary phase converter to deliver true sinusoidal AC; or the complete rewinding of the motor to run directly on a single-phase line. The static phase converter approach is simple and cheap, but with fixed capacitors it can only be tuned to approximate the correct phase shift for a single operating point of the motor. With other than a true 120° phase shift, power will be lost and the motor will not operate efficiently.