Effects of Combined Mode of Operation on Normal Operation of BLDC Motor

Abstract

Brushless DC machines can be operated as motor as well as generator alternatively or simultaneously. Simultaneous operation of this machine as a motor and generator is know as combined mode of operation . During this mode of operation, back emf at un-energized phase is utilized as a generator action while other two energized phases constitute the motor operation. However utilization of this machine as a generator during motor operation affects its proper motor action. Effects of utilizing motor as a generator during motor action on normal operation of BLDC motor are studied in this paper. Simulink model is developed and two case studies are presented to compare motor mode with combined mode of operation of BLDC machine.