Abstract In LLC resonant converter, the accurate analysis of the resonant current can realize the loss calculation of the converter. Based on the existing approximate fitting methods, an improved current analytical method for LLC resonant converter is proposed in this paper. The charging and discharging processes of the output junction capacitor of switching devices in the dead-time are detailed analyzed. Then the changes of the resonant current in the dead-time are analyzed. Moreover, the calculation method of initial values in the improved resonant current analytical expression is modified correspondingly. The resonant current calculated by the proposed method can describe the changes of the resonant current in the dead-time more accurately. The simulation results show that compared with previous methods, the resonant current calculated by the proposed method is more accurate in the dead-time. In addition, comparing the initial values and the peak values of the magnetizing current obtained by other methods, the error of the proposed method is smaller. The experimental results further prove the effectiveness and correctness of the proposed analytical method of the resonant current.
Jiao Jian,Guo Xizheng,You Xiaojie等. An Improved Current Analytical Method for LLC Resonant Converter[J]. Transactions of China Electrotechnical Society, 2021, 36(23): 5002-5013.
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2021, Vol. 36 
