D-Σ CURRENT CONTROL FOR NON-INVERTING BUCK-BOOST PFC CONVERTER WITH WIDE INDUCTANCE VARIATION

摘要

This paper presents the division-summation (D-Σ) current control of a non-inverting buck-boost converter with wide inductance variation to reach the wide output voltage range, unity power factor, and reduce cogging torque of Brushless DC (BLDC) motor. The wide output voltage of the non-inverting buck-boost converter is designed with proposed control method for a variable speed motor application. To reduce the switching loss, the dual-mode operation between buck and boost modes of the non-inverting buck-boost is determined according to the instantaneous input and output voltage. In the proposed system, the digitally micro-controller is used to implement D-Σ current control; this method can improve the performance of the PF and THD. Experimental results show that the proposed 1 kW converter with D-Σ control with wide inductance variation can achieve high power factor and cogging torque of BLDC motor, while maintaining a very wide output voltage.