高频Buck变换器输出电压纹波理论分析与实验测量

Buck变换器广泛用于服务器供电电源等场合。提高开关频率可降低变换器体积，但寄生参数对输出电压纹波的影响不可忽略，本文针对此现象展开研究。首先根据Buck变换器高频等效电路模型，求解输出电压数学表达式，推导输出电压纹波变化规律及相应的判定条件，提出输出电容支路上寄生参数影响输出电压纹波大小的结论。通过设计高频同步Buck变换器实验方案，并选用高带宽的测试设备和最小测试环路，实现了对高频电压纹波正确的实验测量，验证了理论分析的正确性。该研究为Buck变换器的电路设计提供理论依据，并为高频实验测量提供相关经验。

Theoretical analysis and experimental measurement of the output voltage ripple of high switching frequency Buck converter

Buck converter is commonly used in computer servers and other power supplies. Increasing the switching frequency can reduce the volume of the converter, but the effect of parasitic parameters on the output voltage ripple cannot be ignored. The output voltage ripple of Buck converter is studied in this paper. According to the high frequency equivalent circuit model, the output voltage mathematical expression is solved, the output voltage ripple variations and conditions are obtained, and the conclusion that parasitic parameters affect the value of output voltage ripple is proposed. By designing the experimental prototype of high switching frequency synchronous Buck converter, selecting high bandwidth test equipment and minimum test loop, the experimental measurement of high frequency voltage ripple is actualized, and the correctness of theoretical analysis is verified. This study provides a theoretical basis for the circuit design of Buck converter, and provides relevant experience for high switching frequency experimental measurement.