A novel control concept for high-efficiency power conversion with the bidirectional non-inverting buck-boost converter

This paper presents a novel control concept for the bidirectional non-inverting buck-boost converter to achieve extreme high-efficiency power conversion. The duty cycle, duty ratios and time delays of the PWM control signals for the switches are modulated depending on operating points to minimize the power losses in the converter. A 3kW prototype of the converter using SiC MOSFETs has been designed and tested for the verification of the control concept. Measurement results show that the prototype achieves power efficiency between 97.79% and 99.60% over a power range “input voltage from 300V to 500V, output voltage from 200V to 600V and output current from 1A to 5A”.