Direct Power Control of Dual Active Bridge Bidirectional DC-DC Converter

Abstract

This paper presents a DC-DC bi-directional dual active bridge (DAB) power converter, and simulating direct power control (DPC) control for the power converter. The DPC control enables it to have an enhanced dynamic response with improved dc-link voltage stability while controlling the power flow. The output voltage is controlled by the amount of power flow while the power flow depends on the phase shift ratio between primary and secondary bridge. With the DPC control presented here, the control reference is calculated from output voltage and load current, and subsequently phase shift ratio is computed, thereby controlling the power flow. The fast control over the amount power flow provides an overall enhanced performance with improved reference voltage tracking as well as robustness against input voltage fluctuation and load variation. The proposed control scheme is simulated in Matlab Simulink environment.