Digital control of sensorless brushless DC motor drive system with power factor correction for air conditioners

Nowadays, the brushless dc (BLDC) motor has been gained more attention in air conditioner applications as the energy efficiency requirement is concerned. The type of motor using as fans or compressor is gradually changed from induction motor to BLDC motor. The main advantages of BLDC motor are high efficiency, compact structure, and high power density, comparing with induction motor. In addition, the power quality of BLDC driver board such as the low line current harmonics and unity power factor (PF) is desired in order to meet the EN 61000-03-2 standard. In this paper, the sensorless drive system of BLDC motor with power factor correction is digitally implemented. Experimental results are presented to validate the successfully implementing system.