Abstract
Nonlinearities and external disturbances, like dead-time effect, the on-state voltage drop of the power device, and load variations, can lead to tracking errors in the output voltage of dual-active-bridge (DAB) converters. To address these issues, first of all, a generic dynamic model for DAB converters is proposed, which integrates the DAB circuit model with the phase-shift control scheme. Then, an uncertainty and disturbance estimator (UDE) based voltage control scheme for DAB converters is proposed to improve the output tracking accuracy and dynamic performance. Using the proposed power model, the design procedure of the UDE controller is significantly simplified. Hardware-in-the-loop simulations as well as experimental studies on a scale-down prototype are performed to demonstrate the enhanced tracking and disturbance rejection performance of the proposed controller.