PROJECT TITLE :

A Current Control Scheme of Brushless DC Motors driven by Four-Switch Three-Phase Inverters - 2017

ABSTRACT:

Primarily based on the brushless dc motor driven by a four-switch 3-section inverter (FSTPI), a current management scheme is proposed to cut back this ripple of both the conventional conduction region and the commutation region. Assuming c-phase winding is connected to the center point of a dc-link capacitance, in the traditional conduction region when a-part and b-part windings conduct, this of c-section could not be zero as a result of of c-part back electromotive force. The proposed strategy adds 2 regulating vectors into every management cycle based mostly on the ancient PWM theme, and controls the c-part current to be zero by controlling the operating time of the regulating vectors in each management cycle. In the commutation region, the noncommutated phase or the outgoing phase switch is modulated by comparing the amendment rate of the incoming and outgoing part currents to take care of the noncommutated section current constant. Compared with the traditional current management strategy, smart management effect is kept in both the normal conduction region and the commutation region by accurately controlling the working time of the voltage vectors. The proposed strategy will not want to regulate the parameters of the controller, and it's simple and straightforward to implement. The experimental results prove the correctness and effectiveness of the management strategy.