三电平LLC变换器的混合调制策略研究  

Research on Hybrid Modulation Strategy for Three-level LLC Converter

作　　者：刘耿博 曹彦哲 史栋毅 高枫 张雷 刘学钢 LIU Gengbo;CAO Yanzhe;SHI Dongyi;GAO Feng;ZHANG Lei;LIU Xuegang(Xi'an Megmeet Electrical Co.,Ltd.,Xi'an,Shaanxi 710062,China)

机构地区：[1]西安麦格米特电气有限公司,陕西西安710062

出　　处：《控制与信息技术》2021年第4期37-42,共6页CONTROL AND INFORMATION TECHNOLOGY

基　　金：陕西省重点新产品开发项目(MR750-40)-(2017-197号)。

摘　　要：三电平LLC变换器采用单一的轻载定频调宽或全电压范围调频策略时,不能兼顾满足宽输出增益和良好的软开关特性要求。为此,文章通过对采用定频与变频调制方式时三电平LLC变换器开关管特性进行详细分析,提出一种基于定频和变频的混合调制策略,其可很好地实现逆变管的零电压开通(ZVS)与整流二极管的零电流关断(ZCS)。通过一台输出电压范围为200~500 V、输出功率为20 kW的样机进行实验,结果表明,采用该方法的三电平LLC变换器具有良好的ZVS和ZCS特性,且输出电压动态响应快、输出超调小,验证了该控制策略的可行性与优越性。It adopts a single light-load fixed-frequency modulation or full-voltage range frequency conversion strategy for three-level LLC converter,which cannot take into account the widely output gain and good soft switching characteristics.This paper proposes a hybrid modulation strategy based on fixed-frequency modulation and frequency conversion modulation through detailed analysis of its various modulation modes and characteristics,which well realizes zero voltage switch(ZVS)of inverter and zero current switch(ZCS)of rectifier diode.Experiment is carried out through a prototype that its output voltage range is 200~500 V and output power is 20 kW,and the results show that this method can make the three-level LLC converter have good ZVS and ZCS characteristics,fast output voltage dynamic response and small output overshoot,which further proves the feasibility and superiority of the control strategy.

关 键 词：充电桩 LLC变换器 混合调制 调频 调宽 

分 类 号：TP273.1[自动化与计算机技术—检测技术与自动化装置]