A brushless DC motor is disclosed, in which a commercial AC source is full-wave rectified by a rectifier and then converted into a generally flat and low DC voltage not more than 45V by a DC voltage converter. The low DC voltage is applied in a full-wave driving method to a stator coil via an inverter circuit formed of switching elements in a bridge configuration. This structure allows obtaining the brushless DC motor coupled directly to the AC source, and the torque ripples and uneven rotation of the motor are suppressed.