Four-Quadrant Power Control with Frequency Modulation of Bidirectional Dual-Active-Bridge DC/DC Converters in Distributed Generation Systems

Abstract

Frequent four-quadrant power flow change is a key characteristic for distributed generation systems, where distributed energy storage systems play an import role in manipulating power balancing between various sources and loads. This article proposes a novel frequency-modulation method for bidirectional dual-active-bridge (DAB) dc/dc converters, which can achieve four-quadrant instantaneous power control in a simple, efficient, and reliable way. Fast transient response can be realized, and the state of the DAB converter can reach steady within one switching cycle. The theory has been implemented by a DAB prototype in the laboratory and its correctness has been verified by the experimental results.