Device and method of driving BLDC motor and increasing driving speed of BLDC motor

A device to drive a brushless DC (BLDC) motor, the device comprising:

• a rectifier converting an AC voltage into a DC voltage;
• an inverter converting the DC voltage into an AC voltage and supplying the AC voltage to the BLDC motor;
• and
• a microcomputer having a position detecting unit detecting a position of a rotor of the BLDC motor by detecting a time point when a terminal voltage is ½ of an output voltage of the rectifier, when a driving speed of the BLDC motor is less than a rated speed, and by detecting any time point of a period when the terminal voltage is in a range from 0 to ½ of the output voltage of the rectifier, when the driving speed of the BLDC motor is greater than or equal to the rated speed.

A device to driving a brushless DC (BLDC) motor, the device comprising:

• a rectifier converting an AC voltage into a DC voltage;
• an inverter converting the DC voltage into an AC voltage by switching a plurality of power switches and supplying the converted AC voltage to the BLDC motor;
• and
• a microcomputer detecting a position of a rotor and performing phase switching before a terminal voltage of the BLDC motor exceeds ½ of an output voltage of the rectifier when the BLDC motor is driven.