BRUSHLESS MOTOR DRIVE DEVICE FOR COMPRESSOR OF AIR CONDITIONER

PROBLEM TO BE SOLVED: To obtain an overcurrent protection stop function and a current control function for avoiding the demagnetization of a magnet when an overcurrent flows to a stator winding, while maximally securing a load range of a brushless motor. SOLUTION: In the brushless motor drive device for a compressor of an air conditioner, the brushless motor drive device includes two kinds of currents which are a threshold current of the current control function for reducing a frequency of the brushless motor 3 when a motor phase current is not lower than a threshold on the basis of the motor phase current which is operated by a phase current operation part 5-1 on the basis of an output of a DC detection circuit 6, and a threshold current of the overcurrent protection stop function determined by a voltage comparison circuit 7 which is lower than a demagnetization current, according to an output of a compressor temperature sensor 4 from the compressor. COPYRIGHT: (C)2009,JPO&INPIT