Title :
Current-mode sensorless control of single-phase brushless DC fan motors
Author :
Chen, Wei-Chao ; Tzou, Ying-Yu
Author_Institution :
Dept. of Electr. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
This paper proposes a new control scheme for the implementation of a low-cost and high efficiency sensorless speed control IC for single-phase brushless dc (BLDC) fan motors. The proposed control scheme detects the zero-crossing-point (ZCP) of the measured back-EMF to generate commutation signals without Hall sensor. A current mode soft switching scheme is used to smooth the current spikes induced by the reduction of the back-EMF when the rotor is crossing the commutation boundary. An adaptive blanking time control strategy is used to adjust the time interval to ensure correct detection of the ZCP. An open-loop constant Ampere/Hertz ramping control scheme is developed for the startup control from zero speed and switching to sensorless mode once the ZCP is detected. The proposed sensorless control scheme has been verified by using computer simulation based on a developed single-phase BLDC fan motor model. Experimental verification of the proposed control scheme has been carried out by using digital implementation technique. Experimental results reveal the superior performance of the proposed control scheme.
Keywords :
brushless DC motors; sensorless machine control; velocity control; adaptive blanking time control strategy; back-EMF; current mode soft switching scheme; current-mode sensorless control; digital implementation technique; open-loop constant Ampere/Hertz ramping control scheme; sensorless speed control IC; single-phase brushless DC fan motors; startup control; zero-crossing-point; Brushless DC motors; Commutation; Permanent magnet motors; Rotors; Torque; adaptive blanking time control; digital motor control IC; sensorless control; single-phase brushless dc fan motor; soft commutation; soft start-up control;
Conference_Titel :
Power Electronics and Drive Systems (PEDS), 2011 IEEE Ninth International Conference on
Conference_Location :
Singapore
Print_ISBN :
978-1-61284-999-7
Electronic_ISBN :
2164-5256
DOI :
10.1109/PEDS.2011.6147322