Abstract：In order to make the switching frequency of constant on-time(COT)control technique immunity to the variation of input voltage, input voltage feed-forward compensated COT (IVFC-COT) control technique is proposed in this paper. By introducing input voltage feed-forward compensation, the on time is inverse proportion to the input voltage, and the effect of input voltage variation on switching frequency is eliminated. Similar to COT control technique, IVFC-COT also has simple control loop and fast transient response, moreover, error amplifier and its corresponding compensation network are not needed. In addition, it can make the switching frequency independent of the variation of input voltage and load. Simulation and experimental results are verified the validity of the proposed IVFC-COT control technique.
王金平, 许建平, 兰燕妮, 徐杨军. 基于输入电压前馈补偿的开关变换器恒定导通时间控制技术[J]. 电工技术学报, 2012, 27(2): 18-22.
Wang Jinping, Xu Jianping, Lan Yanni, Xu Yangjun. Constant on-Time Control of Switching DC-DC Converters Based on Input Voltage Feed-Forward Compensation. Transactions of China Electrotechnical Society, 2012, 27(2): 18-22.
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