Sensorless Operation of Brushless DC Motor Drive using Back EMF Technique

The Brushless Direct Current (BLDC) motors are one of the motor types that is gaining rapid popularity. Its major appliances include refrigerators, washing machines, vacuum cleaners, freezers, etc. As the name implies, BLDC motors do not use brushes for commutation; instead, they are electronically commutated. This paper proposes a new optimized technique for the Sensorless operation of permanent magnet brushless direct current (BLDC) motor, which is based on back Electro Motive Force (back EMF), Zero Crossing Detection (ZCD). This proposed commutation technique of BLDC motor significantly reduces sensing circuits and cost of motor drive