DRIVING METHOD AND DRIVING DEVICE FOR SINGLE-PHASE ALTERNATING-CURRENT SYNCHRONOUS MOTOR

摘要

The phase (fia) of a winding current (ia) is found from the measured value of the winding current (ia). Counter electromotive voltage (ea) is found from the measured value of motor voltage (Va), and the phase (fea) of the counter electromotive voltage (ea) is found. The phase difference between the phase (fia) of the winding current (ia) and the phase (fea) of the counter electromotive voltage (ea) is found as ?a= fea- fia, and the present load angle (?pv) is found as ?pv=90°-?a. The value of motor voltage (V) (Va, Vb) to an inductor motor is adjusted so as to satisfy ?pv=?sp. Consequently, high efficiency can be always maintained regardless of adjustment and secular changes without using a single-phase inverter and a position sensor.