Fault location for distribution feeders short circuit especially single-phase grounding fault is an important task in distribution system with non-effectively grounded neutral.Fault location mode for distribution feed...Fault location for distribution feeders short circuit especially single-phase grounding fault is an important task in distribution system with non-effectively grounded neutral.Fault location mode for distribution feeders using fault generated current and voltage transient traveling waves was investigated.The characteristics of transient traveling waves resulted from each short circuit fault and their transmission disciplinarian in distribution feeders are analyzed.This paper proposed that double end travelling waves theory which measures arriving time of fault initiated surge at both ends of the monitored line is fit for distribution feeders but single end traveling waves theory not.According to different distribution feeders,on the basis of analyzing original traveling waves reflection rule in line terminal, Current-voltage mode,voltage-voltage mode and current-current mode for fault location based on traveling waves are proposed and aerial mode component of original traveling waves is used to realize fault location.Experimental test verify the feasibility and correctness of the proposed method.展开更多
The neutral grounding mode of medium-voltage distribution network decides the reliability, overvoltage, relay protection and electrical safety. Therefore, a comprehensive consideration of the reliability, safety and e...The neutral grounding mode of medium-voltage distribution network decides the reliability, overvoltage, relay protection and electrical safety. Therefore, a comprehensive consideration of the reliability, safety and economy is particularly important for the decision of neutral grounding mode. This paper proposes a new decision method of neutral point grounding mode for mediumvoltage distribution network. The objective function is constructed for the decision according the life cycle cost. The reliability of the neutral point grounding mode is taken into account through treating the outage cost as an operating cost. The safety condition of the neutral point grounding mode is preserved as the constraint condition of decision models, so the decision method can generate the most economical and reliable scheme of neutral point grounding mode within a safe limit. The example is used to verify the feasibility and effectiveness of the decision method.展开更多
Combined with actual situation of Fengxian power Supply Company, the neutral grounding modes of Fengxian 35 kV and 10 kV power grid are studied in the paper. The different frequencies injected method is used to measur...Combined with actual situation of Fengxian power Supply Company, the neutral grounding modes of Fengxian 35 kV and 10 kV power grid are studied in the paper. The different frequencies injected method is used to measure the capacitive current of Fengxian 28 substations, and the neutral grounding modes of the 28 substations are determined based on the measured values of capacitive current.展开更多
针对某市10 k V配电网中性点运行方式存在的问题,提出一种结合中性点经电阻接地和经消弧线圈接地的优化改造方案。用ATP-EMTP建立10 k V配网单相接地故障仿真模型,在两种不同中性点接地方式下,模拟多种单相接地故障。理论分析及仿真实...针对某市10 k V配电网中性点运行方式存在的问题,提出一种结合中性点经电阻接地和经消弧线圈接地的优化改造方案。用ATP-EMTP建立10 k V配网单相接地故障仿真模型,在两种不同中性点接地方式下,模拟多种单相接地故障。理论分析及仿真实验表明,该新型接地方式可有效抑制单相接地时刻的瞬态过电压,当接地故障发生于架空线末端时,中性点、母线和故障点上的瞬态过电压降幅分别为34.7%、25.3%和18.5%;同时,该新型接地方式能够避免虚幻接地现象发生,并且在发生永久性单相接地故障时,可以通过切换并联电阻以实现准确的故障选线。该新型接中性点地方式对于配网安全可靠运行具有重要意义。展开更多
基金supported by Natural Science Foundation of Shandong Province(ZR2009FM054)
文摘Fault location for distribution feeders short circuit especially single-phase grounding fault is an important task in distribution system with non-effectively grounded neutral.Fault location mode for distribution feeders using fault generated current and voltage transient traveling waves was investigated.The characteristics of transient traveling waves resulted from each short circuit fault and their transmission disciplinarian in distribution feeders are analyzed.This paper proposed that double end travelling waves theory which measures arriving time of fault initiated surge at both ends of the monitored line is fit for distribution feeders but single end traveling waves theory not.According to different distribution feeders,on the basis of analyzing original traveling waves reflection rule in line terminal, Current-voltage mode,voltage-voltage mode and current-current mode for fault location based on traveling waves are proposed and aerial mode component of original traveling waves is used to realize fault location.Experimental test verify the feasibility and correctness of the proposed method.
文摘The neutral grounding mode of medium-voltage distribution network decides the reliability, overvoltage, relay protection and electrical safety. Therefore, a comprehensive consideration of the reliability, safety and economy is particularly important for the decision of neutral grounding mode. This paper proposes a new decision method of neutral point grounding mode for mediumvoltage distribution network. The objective function is constructed for the decision according the life cycle cost. The reliability of the neutral point grounding mode is taken into account through treating the outage cost as an operating cost. The safety condition of the neutral point grounding mode is preserved as the constraint condition of decision models, so the decision method can generate the most economical and reliable scheme of neutral point grounding mode within a safe limit. The example is used to verify the feasibility and effectiveness of the decision method.
文摘Combined with actual situation of Fengxian power Supply Company, the neutral grounding modes of Fengxian 35 kV and 10 kV power grid are studied in the paper. The different frequencies injected method is used to measure the capacitive current of Fengxian 28 substations, and the neutral grounding modes of the 28 substations are determined based on the measured values of capacitive current.
文摘针对某市10 k V配电网中性点运行方式存在的问题,提出一种结合中性点经电阻接地和经消弧线圈接地的优化改造方案。用ATP-EMTP建立10 k V配网单相接地故障仿真模型,在两种不同中性点接地方式下,模拟多种单相接地故障。理论分析及仿真实验表明,该新型接地方式可有效抑制单相接地时刻的瞬态过电压,当接地故障发生于架空线末端时,中性点、母线和故障点上的瞬态过电压降幅分别为34.7%、25.3%和18.5%;同时,该新型接地方式能够避免虚幻接地现象发生,并且在发生永久性单相接地故障时,可以通过切换并联电阻以实现准确的故障选线。该新型接中性点地方式对于配网安全可靠运行具有重要意义。
