Sensorless control of the BLDC motors from near zero to high speed

This paper presents the theory and practice required to implement a novel sensorless operation technique for the brushless DC (BLDC) motor. The proposed new sensorless drive method breaks through the chronic problem of the sensorless BLDC motor drives, lack of low speed operation, so that it ensures highly accurate, robust sensorless operation from near zero to high speed. For this purpose, a physically insightful, speed-independent function, based on a new flux linkage function, is used. A simulation result of the proposed sensorless method is shown, and the result discussed. Also, the validity of the proposed method is verified through the experimental results.