LLC Resonant Converter with Wide Output Voltage Control Ranges Operating at A Constant Switching Frequency

摘要

In this paper, an LLC resonant converter with a wide output voltage control range operating at a constant switching frequency is presented. The proposed converter provides a wide controllable output voltage (V_o～8V_o) with high efficiency over a wide load range. The LLC resonant converter's primary switching devices (Q_1-Q_4) are configured to operate in the half-bridge/full-bridge operating modes and the auxiliary switches (S_(A1), S_(A2)) are turned on and off to meet the required voltage gain characteristic. The feasibility of the proposed converter is verified with experimental results of a 2kW prototype.