Integrated Single-Stage Driver for BLDC Motors

An integrated single-stage drive circuit is proposed for BLDC motors in this study. Compared with the conventional two-stage driver topology, the controller complexity is relative simpler. Only one switch is gated with high frequency PWM control signal and the rest six switches are gated with low frequency six-step square-wave commutation control signals to reduce the switching power losses. The proposed driver is also capable of step up/down operations for driving the BLDC motor with variable input battery voltage. A prototype with 600W rated power is constructed to verify the validity and performance of the proposed integrated drive circuit.