Simplified Implementation of Optimized Triple Phase Shift Control for DAB Converters in Electric Vehicles

Dual active bridge (DAB) converter is a fully-isolated bidirectional DC-DC converter widely used for electric vehicle applications. DAB converter control primarily relies on phase shift control and advanced control techniques with multiple degrees of freedom have been used for optimal converter performance. This work presents a framework to optimize triple phase shift (TPS) control for loss minimization in DAB converters and a simplified control architecture to implement the optimal control with fast and stable dynamic response. Optimized control techniques often calls for look-up table (LUT) based approaches or regression model based approaches for control implementation, which results in complex control architectures with significant utilization of controller resources. The proposed control system in this work minimizes the L UT usage into a single L UT with a simplified linear model to input the optimal pulse widths. A feedback control system with improved dynamic performance is used to input the optimal phase shift. Compared to previous works, the proposed method reduces controller memory usage and computational time, while allowing for a simplified implementation. The proposed control system is verified using a simulation based study for a DAB converter in an electric vehicle application rated at 610–850 VI 48 VI 3.6 kW through efficiency and controller resource comparison, and dynamic analysis.