This paper introduced correlation method to locate transmission line fault.First it described the principle of transmission line fault location based on traveling waves.The principle of correlation analysis is introdu...This paper introduced correlation method to locate transmission line fault.First it described the principle of transmission line fault location based on traveling waves.The principle of correlation analysis is introduced,then the method using correlation analysis in fault location is given.Transmission line model is established with EMTP-ATP.Basing on the model,some kinds of fault are simulated.The feasibility of this algorithm is proved based on simulation results.By comparing with the classical wavelet analysis,this paper gave the advantages of this algorithm in two cases:noise influence suppression and accuracy of near distance fault location.Experiment is established to simulate transmission line grounding fault.The experiment result showed the correlation algorithm's validity.All the analysis result indicated that the correlation algorithm have a high precision.展开更多
The single phase grounding fault location is the focus which researchers pay attention to and study in power system. The accurate fault location can lighten the patrolling burden, and enhance the reliability of the po...The single phase grounding fault location is the focus which researchers pay attention to and study in power system. The accurate fault location can lighten the patrolling burden, and enhance the reliability of the power network. It adopts A/D which has high speed, and uses TMS320VC5402 DSP chip as the system core. This paper presented theory of operation based on traveling waves and achieved software and hardware in detail.展开更多
Anewfault location algorithmfor double-circuit transmissionlines is described inthis paper.Theproposed method uses data extractedfromtwo ends of the transmissionlines andthus eliminates the effects ofthe source impeda...Anewfault location algorithmfor double-circuit transmissionlines is described inthis paper.Theproposed method uses data extractedfromtwo ends of the transmissionlines andthus eliminates the effects ofthe source impedance andthe fault resistance.The distributed parameter model and the modal transformationare also employed.Depending on modal transformation,the coupled equations of the lines are converted intodecoupled ones.Inthis way,the mutual coupling effects between adjacent circuits of the lines are eliminatedandtherefore an accurate fault location can be achieved.The proposed methodis tested via digital simulationusing EMTP in conjunction with MATLAB.The test results corroborate the high accuracy of the proposedmethod.展开更多
针对全并联自耦变压器(auto-transformer,AT)牵引网故障点反射波波头微弱难辨识,且线路并联结构导致故障行波折反射复杂而造成定位困难的问题,提出基于变分模态分解(variational mode decomposition,VMD)和改进能量算子的牵引网故障行...针对全并联自耦变压器(auto-transformer,AT)牵引网故障点反射波波头微弱难辨识,且线路并联结构导致故障行波折反射复杂而造成定位困难的问题,提出基于变分模态分解(variational mode decomposition,VMD)和改进能量算子的牵引网故障行波单端定位方法。首先,深入分析牵引网故障行波的传输特性,研究全并联结构对行波折反射的影响,确定不同故障类型和潮流特征,以此为依据提取故障特征量,将波头辨识转化为能量突变值提取;随后,利用VMD去噪提取电压行波真实分量,再针对第二反射波波头微弱难标定问题,在滑动时间窗口(sliding time window,STW)下,结合对称差分能量算子(symmetrical differencing energy operator,SDEO)构造故障信号的二次瞬时能量谱,效果良好。仿真结果表明:所提方法抗过渡电阻能力强,能够反应不同工况下故障牵引网电磁能量的变化,具有较高的定位精度。展开更多
线缆混合输电线路故障时将出现更加复杂的行波折反射现象,对于故障测距带来不小的难度。为解决此类问题,根据电缆与架空线各自的结构、特性的不同,在输电线路上安装分布式的行波检测装置将线路分成若干区间。应用皮尔逊相关系数的相关...线缆混合输电线路故障时将出现更加复杂的行波折反射现象,对于故障测距带来不小的难度。为解决此类问题,根据电缆与架空线各自的结构、特性的不同,在输电线路上安装分布式的行波检测装置将线路分成若干区间。应用皮尔逊相关系数的相关性原理,确定故障发生的区间。通过详细的公式推导,抵消掉波速对测距精度的影响,利用第二个SVD(singular value decomposition)分量标定出信号奇异点的脉冲模极大值,推导出分区间不含波速的混合线路故障定位算法。通过PSCAD仿真及MATLAB数据处理结果表明,与常规的单双端测距法应用于线缆组成的混合输电线路相比,可进一步提高测距精度。展开更多
气体绝缘金属封闭输电线路(gas insulated metal enclosed transmission lines,GIL)在运输及安装过程中易遗留绝缘隐患,进而引发内部电弧故障。内部电弧故障的接地电流特性对GIL设备的绝缘诊断及故障定位工作具有重要应用价值。针对上...气体绝缘金属封闭输电线路(gas insulated metal enclosed transmission lines,GIL)在运输及安装过程中易遗留绝缘隐患,进而引发内部电弧故障。内部电弧故障的接地电流特性对GIL设备的绝缘诊断及故障定位工作具有重要应用价值。针对上述问题,该文提出了基于动态电弧理论的GIL仿真模型,并开展不同运行工况下的接地电流特性研究。研究通过Mayr-Schwarz电弧及Bergeron传输线理论,结合GIL设计参数,搭建了正常运行与内部电弧故障工况下的电磁暂态程序(electric magnetic transient program,EMTP)仿真模型,并对2种工况三相短接排的接地电流特性展开特性分析。结果表明,正常运行工况下的短接排将流过近似对称的三相工频电流,接地电流幅值不超过额定负载电流的1%。GIL内部发生电弧故障后,将产生沿GIL管廊两侧传播的故障电流行波,接地电流将在纳秒级时间内发生突变,并出现幅值可达7kA的微秒级故障暂态电流衰减过程。最后,基于真型GIL的模拟脉冲测试,验证了基于暂态电流法GIL故障定位方案的可行性。仿真结果可为GIL设备的绝缘设计及故障定位提供参考。展开更多
基金Project Supported by Chongqing Science and Technology Committee(2005AA600)
文摘This paper introduced correlation method to locate transmission line fault.First it described the principle of transmission line fault location based on traveling waves.The principle of correlation analysis is introduced,then the method using correlation analysis in fault location is given.Transmission line model is established with EMTP-ATP.Basing on the model,some kinds of fault are simulated.The feasibility of this algorithm is proved based on simulation results.By comparing with the classical wavelet analysis,this paper gave the advantages of this algorithm in two cases:noise influence suppression and accuracy of near distance fault location.Experiment is established to simulate transmission line grounding fault.The experiment result showed the correlation algorithm's validity.All the analysis result indicated that the correlation algorithm have a high precision.
文摘The single phase grounding fault location is the focus which researchers pay attention to and study in power system. The accurate fault location can lighten the patrolling burden, and enhance the reliability of the power network. It adopts A/D which has high speed, and uses TMS320VC5402 DSP chip as the system core. This paper presented theory of operation based on traveling waves and achieved software and hardware in detail.
文摘Anewfault location algorithmfor double-circuit transmissionlines is described inthis paper.Theproposed method uses data extractedfromtwo ends of the transmissionlines andthus eliminates the effects ofthe source impedance andthe fault resistance.The distributed parameter model and the modal transformationare also employed.Depending on modal transformation,the coupled equations of the lines are converted intodecoupled ones.Inthis way,the mutual coupling effects between adjacent circuits of the lines are eliminatedandtherefore an accurate fault location can be achieved.The proposed methodis tested via digital simulationusing EMTP in conjunction with MATLAB.The test results corroborate the high accuracy of the proposedmethod.
文摘针对全并联自耦变压器(auto-transformer,AT)牵引网故障点反射波波头微弱难辨识,且线路并联结构导致故障行波折反射复杂而造成定位困难的问题,提出基于变分模态分解(variational mode decomposition,VMD)和改进能量算子的牵引网故障行波单端定位方法。首先,深入分析牵引网故障行波的传输特性,研究全并联结构对行波折反射的影响,确定不同故障类型和潮流特征,以此为依据提取故障特征量,将波头辨识转化为能量突变值提取;随后,利用VMD去噪提取电压行波真实分量,再针对第二反射波波头微弱难标定问题,在滑动时间窗口(sliding time window,STW)下,结合对称差分能量算子(symmetrical differencing energy operator,SDEO)构造故障信号的二次瞬时能量谱,效果良好。仿真结果表明:所提方法抗过渡电阻能力强,能够反应不同工况下故障牵引网电磁能量的变化,具有较高的定位精度。
文摘线缆混合输电线路故障时将出现更加复杂的行波折反射现象,对于故障测距带来不小的难度。为解决此类问题,根据电缆与架空线各自的结构、特性的不同,在输电线路上安装分布式的行波检测装置将线路分成若干区间。应用皮尔逊相关系数的相关性原理,确定故障发生的区间。通过详细的公式推导,抵消掉波速对测距精度的影响,利用第二个SVD(singular value decomposition)分量标定出信号奇异点的脉冲模极大值,推导出分区间不含波速的混合线路故障定位算法。通过PSCAD仿真及MATLAB数据处理结果表明,与常规的单双端测距法应用于线缆组成的混合输电线路相比,可进一步提高测距精度。
文摘气体绝缘金属封闭输电线路(gas insulated metal enclosed transmission lines,GIL)在运输及安装过程中易遗留绝缘隐患,进而引发内部电弧故障。内部电弧故障的接地电流特性对GIL设备的绝缘诊断及故障定位工作具有重要应用价值。针对上述问题,该文提出了基于动态电弧理论的GIL仿真模型,并开展不同运行工况下的接地电流特性研究。研究通过Mayr-Schwarz电弧及Bergeron传输线理论,结合GIL设计参数,搭建了正常运行与内部电弧故障工况下的电磁暂态程序(electric magnetic transient program,EMTP)仿真模型,并对2种工况三相短接排的接地电流特性展开特性分析。结果表明,正常运行工况下的短接排将流过近似对称的三相工频电流,接地电流幅值不超过额定负载电流的1%。GIL内部发生电弧故障后,将产生沿GIL管廊两侧传播的故障电流行波,接地电流将在纳秒级时间内发生突变,并出现幅值可达7kA的微秒级故障暂态电流衰减过程。最后,基于真型GIL的模拟脉冲测试,验证了基于暂态电流法GIL故障定位方案的可行性。仿真结果可为GIL设备的绝缘设计及故障定位提供参考。
