滤波换相换流器的典型故障瞬态谐波仿真研究  

Transient Harmonic Study of Typical Faults in Filter Commutated Converter

作　　者：潘侃[1] 罗隆福[1] 许加柱[1] 李勇[1] 

机构地区：[1]湖南大学电气与信息工程学院,湖南长沙410082

出　　处：《计算机仿真》2011年第4期308-312,共5页Computer Simulation

摘　　要：研究直流输电系统消除故障问题,在稳态工况条件下FFT算法可以满足精度和谐波检测要求,针对系统发生故障的瞬间,系统电流中除特征谐波外,电流中存在间谐波和次谐波等分量。为了有效解决直流输电系统发生故障瞬间谐波频谱泄露,提出了一种结合能量群与消除频谱泄露的复合谐波检测算法,在建立了滤波换相换流器(Filter Commutated Converter,FCC)的HVDC输电系统的基础上,对系统发生极母线对地短路,整流侧交流母线三相接地短路及逆变侧交流母线三相接地短路三种典型故障进行了仿真研究,并对交流母线处的电流进行瞬态谐波检测。结果表明,在交流母线电流中的2次谐波含量发生激增,达到谐波屏蔽的效果,减轻了换流变压器的负担,增强了系统的稳定性,说明复合谐波检测算法在分析故障瞬态电流时,效果满足了要求。FFT analysis,which is commonly applied in harmonic analysis of HVDC power system,is capable for detection and measurement of harmonic in steady state,though for the sake of sub-harmonic and inter-harmonic during the moment of fault,is inaccurate in transient state.In order to eliminate the inaccuracy during the transient due to spectral leakage,this paper presents an enhanced measurement scheme of harmonic,which combines the concept of group energy and spectral leakage elimination algorithm.A simulation study including the fault of the DC bus,3-phase fault of AC bus in rectifier side and 3-phase fault of AC bus in inverter side is carried out.With the HVDC power distribution system platform base on Filter Commutated Converter,the new harmonic identification scheme is applied on the AC bus in rectifier side.The result of simulation shows that during these three typical faults,2nd harmonic is increased drastically,and compare with the FFT harmonic identification algorithm,less pit-falls and peaks are observed in the waveform when the fault is existing,which indicates that the new scheme can reveal more characteristic and information of the original harmonic signal on analysis of transient harmonic.

关 键 词：谐波群 瞬态谐波 滤波换相换流器 典型故障 谐波特征 

分 类 号：TM743[电气工程—电力系统及自动化]