| 摘要 |
PROBLEM TO BE SOLVED: To provide a brushless motor in which both the circuit efficiency and motor efffciency are satisfied and the leakage current from motor is reduced while sustaining the power factor of AC power supply at 1. SOLUTION: Output of a rectifier circuit 6 is short-circuited through a switching element 5 and a reactor 4 which is short-circuited through a capacitor 2 and a diode 3 connected, on the cathode side, with one end of the reactor 4 closer to the positive output of rectifier circuit 6. The capacitor 2 is connected across a three-phase bridge type switching element group 1 reversely to the direction of current flowing through the rectifier diode 3. The switching element group 1 is connected, on the output, with a brushless motor 14 and a circuit 13, receiving the output voltage waveform and current waveform from the rectifier diode 3 and the voltage across the capacitor 2, controls the output current from the rectifier diode 3 to have a waveform similar to the voltage and the voltage across the capacitor 2 represents a voltage being applied to the brushless motor 14. Means 12 conducts the switching element group 1 selectively depending on the rotational phase of brushless motor 14 connected with the output. |
