• Surender Dhanasekaran Assistant Professor, EEE Department, School of Electrical & Computing, Vel Tech University, Chennai.
  • Nandineravanda Bheemaiah Post Graduate Scholar, Automotive Mechatronics, Vel Tech University, Chennnai.


Back EMF, PMBLDC motor, position sensor-less, fuzzy logic controller (FLC)


Brushless dc (BLDC) motors and their drives are penetrating the market of home appliances, HVAC industry, and automotive applications in recent years because of their high efficiency, silent operation, compact form, reliability, and low maintenance. Traditionally, BLDC motors are commutated in six-step pattern with commutation controlled by position sensors. To reduce cost and complexity of the drive system, sensorless drive is preferred. In this paper, a fuzzy logic controller (FLC) for sensorless brushless dc (BLDC) motor. The proposed FLC is based on the terminal voltage measurement as the sensorless method for BLDC motor control. There are two modules designed in the speed control of BLDC motor, i.e. command and regulating modules. Command module is to find and issue commutation period and PWM duty cycle to the BLDC motor for desired speed. The regulating module is designed by applying a FLC with sensorless technology and is used to regulate the speed of BLDC motor under various disturbances, such as loading effect. A new scheme is proposed for sensor-less control of PMBLDC motor for aligning its rotor at a known position.


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How to Cite

Surender Dhanasekaran, & Nandineravanda Bheemaiah. (2015). INTELLIGENT CONTROL METHODS FOR SENSOR LESS CONTROL OF BLDC MOTOR DRIVE USED IN HIGH SPEED APPLICATIONS. International Education and Research Journal (IERJ), 1(4). Retrieved from