A Negative Sequence Directional Element for High-Voltage Line Protections

Abstract:

In high-voltage lines protections, directional elements based on negative sequence voltages available can not work well when negative voltages protection equipments capture are relatively low, which may lead to malfunctions or failure to actuate. A new directional element based on negative sequence reactance is presented in this paper. The negative sequence reactance is negative and then it is less than the line negative sequence reactance when a forward fault occurs. And when a reverse fault occurs, the negative sequence reactance is greater than the line negative sequence reactance. Hence, which direction a fault occurs can be distinguished according to the sign and the magnitude of the reactance. The direction element based on the negative sequence reactance has high sensitivity with no influence by transition resistances. The directional element proposed can work well when the negative sequence voltage is very low or even close to be zero and it is easy to realize.

• Periodical: Advanced Materials Research (Volumes 614-615)
• Pages: 933-936
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.614-615.933
• Online since: December 2012
• Authors: Xiao Hui Zeng, Hong Song, Si Yan Tao
• Keywords: Direction Element, HV Line, Negative Sequence Reactance, Voltage Threshold

References

[1] Xue Shimin，He Jiali，Li Yongli in: Pilot Protection of ultra-hjgh-Voltage Transmission Line with Negative Sequence Directional Component, Automation of Electric Power Systems, 2007, 31(18): 50-53.

[2] Su Bin, Dong Xinzhou, Shun Yuanzhang, in: Performance of negative sequence directional protection on series compensated ultra-high-voltage transmission line, Automation of Electric Power Systems, 2004, 28(14): 9-13.

[3] XUE Shimin, HE Jiali, LI Yongli, in: Improved Negative Sequence Directional Relay to Response toSymmetrical Three-phase Fault, Proceedings of the CSU-EPSA, 2010，22(2): 1-4.

[4] Ke Xu, Shihong Miao and Pei Liu, in: Performance Analysis of Non-wholly-phase Operation of Negative Sequence Power Directional Elements in High-frequency Protections, Automation of Electric Power Systems, 2003, 27(21): 45-48.

[5] Wang Hui, He Benteng, Li Yiquan, in: Research of CVT's influence on negative-sequence (negative-sequence) direction protection, Relay, 2006, 34(9): 1-3.