Although the dead-time optimization design of resonant converters has been widely researched

classical design methods focus more on achieving zero-voltage switching (ZVS) operation. The body diode loss is always ignored

which results in low-efficiency of the converter

especially

in energy router (ER). To deal with this problem

this paper proposes an adaptive deadtime modulation scheme for bidirectional LLC resonant converters in ER. First

the power loss of the MOSFET is analyzed based on the dead-time. Then

a novel dead-time optimization modulation principle is proposed. It can eliminate the body diode loss of MOSFET compared with existing literature. Based on the optimization modulation principle

this paper proposes an adaptive dead-time modulation scheme. To this end

the converter adopting the scheme no longer needs to calculate dead-time

which simplifies the parameter design process. Meanwhile

this scheme enables dead-time to dynamically change with working conditions according to the dead-time optimization modulation principle. With these effects

the ZVS operation is achieved

and the body diode loss of MOSFET is also eliminated. Furthermore

a digital implementation method is designed to make the proposed modulation scheme have fast-transient response. Finally

experimental results show that the proposed dead-time modulation scheme enables converters to achieve ZVS operation in all working conditions

and has higher efficiency than classical dead-time design methods.