Optimal Dual Active Bridge DC-DC Converter Operation with Minimal Reactive Power for Battery Electric Vehicles Using Model Predictive Control

Abstract

The dual active bridge DC-DC converter is a promising power converter used in several applications. Much research has been focusing on the study of such a converter from different angles. In this paper, an optimal design of the DAB converter is proposed to provide minimal reactive power in addition to reduced weight and size for the converter magnetic components in order to assure the DC-DC conversion stage of battery electric vehicles’ powertrains. Two modes of operation are considered in order to fulfill such a requirement and minimize reactive power of the converter (circulating current/conduction losses): an optimal extended phase shift (EPS) modulation along with an optimal triangular phase shift (TrgPS) modulation. The operation of the DAB converter under the two modes is being driven using a model predictive controller. Simulation results using MATLAB/Simulink presented in the paper show that the operation of the DAB converter for such an application is optimal when operating under optimal TrgPS modulation. In addition to the aforementioned features, it also solves many other concerns, such as transient load fluctuation and input voltage disturbance effects, and provides ease of control.