APPARATUS AND METHOD FOR DRIVING BRUSHLESS DIRECT CURRENT MOTOR WITHOUT POSITION SENSORS

摘要

PURPOSE: An apparatus and a method for driving a BLDC(Brushless DC) motor without a position sensor are provided to control a speed of a BLDC motor by determining a position of a rotor of the BLDC motor in real time without using a sensor for sensing the position of the rotor. CONSTITUTION: A speed controller(20) outputs the current necessary for controlling angular velocity of a BLDC motor. A current controller(30) outputs a voltage command value for driving the BLDC motor. A counter electromotive force observation unit(60) outputs the strength of the counter electromotive force which is calculated by using a voltage command value and an impedance and a resistance of a stator. A coupler outputs an actual speed of the BL DC motor. A PWM(Pulse Width Modulation) circuit unit outputs a PWM control signal for controlling a rotation angle and a speed of the BLDC motor.