摘要
采用小波多尺度奇异性检测行波信号可实现超高压输电线路故障的精确测距。对于不换位或不完全换位线路采用传统解耦方法并不能完全消除三相之间的耦合,因此波头难以鉴别。提出采取实际不对称数值解耦的方法并引进实际模量波速。通过相模变换对三相电流进行解耦处理,对三相输电线路均匀换位和不换位或不完全换位2种情况,分别确定模变换矩阵,求得各模量上的电感和电容参数;应用单端法进行故障测距;用小波变换检测奇异信号,把对行波信号的分析转化为对模最大值的分析。仿真结果表明采用非对称解耦相模变换有效地消除了各相之间的电磁耦合,与采用对称假设时的故障测距结果相比精度有了较大提高。
The scales is used singularity of traveling to accurately locate wave extracted by wavelet transform at different ultra-high voltage transmission line faults. For un -transposed lines,the traditional decoupling methods cannot eliminate the coupling among three phases completely,which brings difficulty in traveling wave surge detection. An unsymmetrical numerical decoupling method is presented and the actual wave velocity is introduced. Firstly,three- phase currents are decoupled by the phase- model transformation. Considering the uniform transposition and un-transposition or incomplete transposition of three -phase transmission lines,the transformation matrix is determined and then used to calculate the inductance and capacitance parameters. The single- terminal fault location method is applied,and the wavelet transform is used to detect the singularity signal,thus the traveling wave signal analysis is transformed to modulus maxima analysis. Simulation results show that the method can decouple each phase efficiently and the precision is greatly increased compared with the method using symmetrical presupposition.
出处
《电力自动化设备》
EI
CSCD
北大核心
2006年第9期54-57,共4页
Electric Power Automation Equipment
关键词
故障测距
小波变换
相模变换
不对称线路
fault locating
wavelet transform
phase-model transformation
unsymmetrical transmission line
