一种新型车载宽输出范围LLC谐振变换器  

A Novel Vehicle-mounted Wide Output Range LLC Resonant Converter

作　　者：廖志凌[1] 潘骁 顾赟 陈兆岭[1] LIAO Zhi-ing;PAN Xiao;GU Yun;CHEN Zhao-ing(Jiangsu University,Zhenjiang 212000,China;不详)

机构地区：[1]江苏大学,电气信息工程学院,江苏镇江212000 [2]国网江阴市供电公司,江苏无锡214400

出　　处：《电力电子技术》2023年第7期107-112,共6页Power Electronics

基　　金：江苏省重点研发计划(BE2019009-2)。

摘　　要：LLC谐振变换器由于具有天然的软开关属性而备受青睐,但电压增益可调范围有限,开关频率范围过宽的缺陷限制了其应用场合。鉴于此,这里提出了一种具有模式切换功能的“I-H”型电路拓扑,并且提出了一种不对称脉宽调制(PWM)控制实现三电平,利用谐振电流周期性特性,在不额外引入开关的前提下保证电容均压。通过模式切换以及控制策略的转换,得到低、中、高3种电压增益模式,在不改变输入电压及谐振元件参数的前提下拓宽了输出电压范围。这里将其与传统的LLC拓扑进行对比,对3种电压增益分别进行了模态分析,并分析了变换器的软开关条件,为参数选取提供依据。最后搭建了一台1500W的实验样机验证了所提电路拓扑及混合控制策略的适应性和准确性。LLC resonant converter is favored because of its natural soft switching characters.However,its voltage gain adjustable range is limited,and the switching frequency range is too wide to limit its application.In view of this,an“I-H”type circuit topology with mode switching function is proposed.And an asymmetric pulse width modulation(PWM)control is proposed to achieve three-level voltage,using the periodic characteristics of the resonant current to ensure the capacitor voltage equalization without introducing additional switches.Through the mode-switching and the conver-sion of the control strategy,three voltage gain modes of low,medium and high are realized.The output voltage range is widened without changing the input voltage and parameters of the resonant element.It is compared with the tradi-tional LLC resonant converter.Model analysis is carried out for the three voltage gains respectively.Then the soft switching conditions of the converter are analyzed to provide the basis for parameter selection.Finally,a 1500 W ex-perimental prototype is built to verify the adaptability and accuracy of the proposed circuit topology and hybrid con-trol strategy.

关 键 词：变换器 宽输出范围 电容均压 模式切换 

分 类 号：TM46[电气工程—电器]