MOTOR DRIVE DEVICE AND REFRIGERATOR UTILIZING SAME

摘要

This motor drive device has: a position detection means (5) that detects a rotational position from a counter electromotive voltage generated by the rotation of a brushless DC motor (4); and an inverter (3) that generates a waveform with an arbitrary frequency on the basis of a position detection signal and drives the brushless DC motor (4). The position detection means (5) has: a phase voltage detection unit (5a) for detecting voltages of respective phases of the brushless DC motor (4); a reference voltage setting unit (5c) for setting a reference voltage; a filter unit (5b) for removing high-frequency components; and a comparison unit (5d) for comparing outputs of the reference voltage setting unit (5c) and the filter unit (5b).