Abstract：A digital control scheme is proposed to improve the light-load efficiency for Buck converters with synchronous rectification. The method adopts a fixed switching frequency at heavy load, and smoothly switches to constant on-time control mode at light load for the purpose of reducing the switching losses. In addition, different from traditional control methods, the proposed approach dynamically estimates the inductor current zero crossing point accurately based on on-time of the drive signal and inductor volt-second balance to force converters work in discontinuous conduction mode, which significantly reduces conduction losses at light loads. These features ensure the converters own higher efficiency over a wide load range. Theoretical analysis and experimental results are provided to verify the proposed scheme.
徐杨. 提高同步整流Buck变换器轻载效率的数字化控制方案分析[J]. 电气技术, 2017, 18(2): 14-19.
Xu Yang. The Analysis of Digital Control Approach to Improve Light-Load Efficiency for Buck Converters with Synchronous Rectification. Electrical Engineering, 2017, 18(2): 14-19.
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