Buck DC-DC变换器扼流圈工作原理及其电感量估算  

Working Principle and Inductance Estimation of Buck DC-DC Converter's Choke

作　　者：陈本竹 

出　　处：《电源世界》2016年第1期29-36,24,共9页The World of Power Supply

摘　　要：Buck DC/DC变换器输出端都设有扼流圈,它与电解电容器和续流二极管共同组成平波电路,将高频脉动电压电流平滑成直流电压电流。平波电路看似很简单,随便给几个参数,即能将变换器"运行起来"。实际上技术参数却不易制作得恰到好处,往往会使某些或全部技术指标达不到要求,从而大大降低变换器的工作稳定可靠性能,甚至根本无法使用。扼流圈中存在许多相互依存的杂散变量,使其设计变得复杂繁琐,设计者必须协调好这些参数。这种协调,是一个不断迭代调整的过程,尽管有磁芯制造商提供的各种数据和图表,可以帮助设计者简化、优化大量不可避免的迭代过程,但还是不能完全替代这项工作。本文给出关于扼流圈工作原理的分析,以及电感量的估算。There is a choke in the output terminal of Buck DC-DC converter.Together with electrolytic capacitor and freewheeling diode,they form the smoothing circuit,changing high-frequency pulse V-I into DC V-I.The smoothing circuit seems to be so simple that several parameters can operate the converter.Actually,suitable technical parameters are not easy to make,which leads to the failure of some or all technical indexes,reducing the converter＇s stability and reliability,even becoming useless.There are many interdependent spurious variables,making the design complex,which designers must coordinate.Such coordination is a constant iterative adjusting process.Although various datum and charts provided by magnetic core manufacturers can help designers simplify and optimize many unavoidable iterative processes,it can＇t replace the work entirely.This paper shows the analysis of choke＇s working principle and the inductance estimation.

关 键 词：降压型(Buck)DC/DC变换器 输出平波电路 扼流圈 连续模式(CCM)临界模式(CCM/DCM) 断续模式(DCM) 

分 类 号：TN86[电子电信—信息与通信工程]