摘要
To reduce output voltage noise and improve dynamic response performance,this study designed a buck converter on the basis of secondary filters and adaptive voltage positioning(AVP).A hybrid control method was proposed for the compensation of the secondary filter.The introduction of a high-frequency feedback path,in addition to the traditional feedback path,effectively improved the influence of the secondary filter on the loop stability and direct current regulation performance.A small-signal model of the buck converter based on the proposed control method was derived,and the stability and selection of control parameters were analyzed.AVP is realized using an easy-to-implement and low-cost control method that was proposed to improve dynamic response performance by changing the low-frequency gain of the control loop and load regulation of the output voltage.The experimental results of the buck converter showed that the proposed method effectively reduced the output voltage noise by 50%and improved the dynamic response capability to meet the target requirements of mainstream electronic systems.
为降低输出电压噪声,改善动态响应性能,设计了一种基于二次滤波器和自适应输出电压调节(AVP)的降压变换器.针对二次滤波器的补偿,提出了一种混合控制方式.在传统的反馈环节外,增加一个高频通路环节,有效改善了二次滤波器对环路稳定性和直流调节性能方面的影响.推导出基于该控制方法的降压变换器的小信号模型,并对其稳定性和控制参数的选取进行了分析.为了实现自适应输出电压调节,提出了一种易于实现且低成本的控制方法,通过改变控制环路低频增益和输出电压负载调整率来改善动态响应性能.降压变换器原型试验结果表明,所提方法可有效降低50%的输出电压噪声,同时改善了动态响应能力,达到目前主流电子系统的指标需求.
