On the feasibility of four-switch three-phase BLDC motor drives for low cost commercial applications: topology and control

The main purpose of this paper is to develop low cost four-switch brushless DC (BLDC) motor drives for practical industrial applications. To drive this system effectively, a novel direct current controlled PWM scheme is designed and implemented to produce the desired dynamic and static speed and torque characteristics. Also, the feasibility of the four-switch converter is extended to the two-phase BLDC motor drives and the six-switch converter for power factor correction and speed control. The operational principle of the four-switch BLDC motor drive and the developed control scheme are theoretically analyzed and the performance is demonstrated by the simulation and experimental results, along with high-speed DSP, TI TMS320C F243.