A Review of Bidirectional On-Board Chargers for Electric Vehicles

Abstract

The fast development of electric vehicles (EVs) provides significant opportunities to further utilize clean energies in the automotive. On-board chargers (OBCs) are widely used in EVs because of their simple installation and low cost. Limited space in the vehicle and short charging time require an OBC to be power-dense and highly efficient. Moreover, the possibility for EVs to deliver power back to the grid has increased the interest in bidirectional power flow solutions in the automotive market. This paper presents a comprehensive overview and investigation on the state-of-the-art solutions of bidirectional OBCs. It reviews the current status, including architectures and configurations, smart operation modes, industry standards, major components, and commercially available products. A detailed overview of the promising topologies for bidirectional OBCs, including two-stage and single-stage structures, is provided. Future trends and challenges for topologies, wide bandgap technologies, thermal management, system integration, and wireless charging systems are also discussed in this paper.

Review on Control Techniques for EV Bidirectional Wireless Chargers

“…To promote the use of V2G wireless controllers, there are still some open issues that must be addressed. Some of them are common with on-board conductive chargers [78], but others are specific for wireless chargers due to the challenges imposed by the wireless power transfer technology. The most significant challenges to achieve fully operative V2G wireless chargers are:…”

“…In order to increase the efficiency of the system, all the diodes are fast body diodes. How to effectively generate the gate signals is still a non-trivial ask as there must be synchronized with other legs in the power converter and even with those in the other power converter [78]. • Synchronisation of the power converters.…”

A Fixed Frequency Zero-Voltage-Switching On-Board EV Charger

“…he lightweight, compact, efficient on-board charger (OBC) is critical for electric vehicles [1]. In order to raise the efficiency of the OBC, SiC and GaN power devices are applied in the OBC to reduce the power device loss and raise the switching frequency [2][3][4][5][6][7][8]. The OBC efficiency is improved by applying the wide band gap power devices [3,5].…”

“…In order to raise the efficiency of the OBC, SiC and GaN power devices are applied in the OBC to reduce the power device loss and raise the switching frequency [2][3][4][5][6][7][8]. The OBC efficiency is improved by applying the wide band gap power devices [3,5]. However, the loss of power devices rises obviously with the increase of the switching frequency.…”

“…However, the loss of power devices rises obviously with the increase of the switching frequency. The soft switching topologies are applied in OBC to further increase efficiency and power density [4][5][6][7][8]. With regards to the conversion topologies, there are three kinds of OBC, such as single stage OBC, two stages OBC and multi-stage OBC.…”