牵引电力电子变压器次谐振现象机理及抑制策略  

Sub-resonance Mechanism and Suppression Strategy for Power Electronic Transformer for Traction

作　　者：刘华东 张志学 陈涛 黄子昊 LIU Huadong;ZHANG Zhixue;CHEN Tao;HUANG Zihao(School of Electrical Engineering,Southwest Jiaotong University,Chengdu 611756,China;CRRC Zhuzhou Institute Co.,Ltd.,Zhuzhou 412001,China)

机构地区：[1]西南交通大学电气工程学院,四川成都611756 [2]中车株洲电力机车研究所有限公司,湖南株洲412001

出　　处：《铁道学报》2021年第6期45-53,共9页Journal of the China Railway Society

基　　金：国家重点研发计划(2017YFB1200900)。

摘　　要：牵引电力电子变压器(PETT)由于单相拓扑结构、高低频率变流器混合使用和死区时间等影响,中间直流侧电压包含以2倍频为主的低次谐波电压。低次谐波电压在LLC变换器谐振回路中被放大,发生次谐振现象。揭示直流侧2倍频等低次频谐波电压在LLC谐振变换器中产生次谐振的机理,讨论次谐振引起ZVS(零电压开通)范围减小和开关管通态损耗增加的原因。定量分析低频谐波电压及其放大系数与网侧功率、直流电容值、直流电压谐波次数和网侧谐波电流的关系。给出PETT系统参数优化选取的方法和抑制低次谐波的控制策略。试验验证了本文所提方法、策略的正确性和有效性。Due to the influence of the single-phase topology,the mixed use of high and low frequency converters,and the dead time of the power electronic transformer for traction(PETT),the intermediate DC voltage contains the second harmonic voltage and other low-frequency harmonic voltage.Because of the amplification of the low-frequency harmonics in the resonant circuit of the LLC converter,the sub resonance occurs.Firstly,the paper revealed the sub-resonant mechanism in the LLC resonant converter caused by the secondary voltage and other low-frequency harmonic voltage on the DC side.Secondly,the reasons for the reduction of the range of Zero Voltage Switch(ZVS)and the increase of the on-state loss of the switch caused by the sub-resonance were discussed.A quantitative analysis was made on the relationship between low frequency harmonic voltage and its amplification factor and network side power,DC capacitor value,DC voltage harmonic number and network side harmonic current.Finally,the method to optimize the selection of PETT system parameters and the control strategy to suppress the low-order harmonics were given.The test verifies the correctness and effectiveness of the methods and strategies mentioned in this paper.

关 键 词：牵引电力电子变压器 高低频变流器混合使用 2倍频谐波电压 次谐振 ZVS 谐波抑制 

分 类 号：TM41[电气工程—电器]