Robust dynamic control of constant-current-source-based dual-active-bridge DC/DC converter used for off-board EV charging

• Main Authors: Ashfaq, Muhammad Husnain, Memon, Zulfiqar Ali, Chaudhary, Muhammad Akmal, Talha, Muhammad, Selvaraj, Jeyraj, Abd Rahim, Nasrudin, Hussain, Muhammad Majid
• Format: Article
• Published: MDPI 2022
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.um.edu.my/46125/; https://www.mdpi.com/journal/energies/about
• Institution: Universiti Malaya

Due to the high power density, inherent zero-voltage-switching (ZVS), and high voltage-conversation ratio, the current source-based isolated dual-active-bridge DAB-DC/DC converters are extensively used for charging EVs under constant-current mode. However, the fast dynamic response of an output current is a crucial requirement for dual-active-bridge DC/DC converters operating as a constant-current source. This study proposes a fast current controller (FCC) for tracking the desired output current under various input/output parameter disturbances/variations. The proposed control strategy can ensure a fast transient response with negligible overshoot/undershoot for output current during start-up and when there are variations in the load or input voltage. Furthermore, the dynamic behavior of the current control against change in the reference current value has also been improved. A constant-current-based DAB-DC/DC converter is modeled and simulated in MATLAB/Simulink software and a scaled-down 300 W lab prototype DAB-DC/DC converter is designed with the TMS320F28335 DSP controller of Texas Instruments. To verify the effectiveness of the proposed current controller, different test cases, such as a change in the load, a change in the input voltage, and a change in the desired output current, are considered. Moreover, under these test cases, the proposed current-control strategy is compared with the conventional proportional-integral (PI) current controller, model-based phase-shift controller (MBPS), and load current feed-forward controller (LCFF). Both the experimental and simulation results have validated the effectiveness of the proposed control strategy.