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| Lightning Shielding Failure Analysis of UHVAC Transmission Lines Based on Improved EGM |
| Yuan Haiyan, Fu Zhengcai, Wei Bengang, Zhao Gang |
| Shanghai Jiaotong University Shanghai 200030 China |
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Abstract Lightning shielding failure is an important issue in addressing lightning performance of an UHVAC transmission lines. It is shown from the operating experience of UHVAC lines in Japan and Russia that the shielding failure rate predicted using the existing Electro-Geometric Model (EGM) does not match with that obtained from operation data. In this paper, an improved EGM is proposed to evaluate shielding failure rate of the UHVAC transmission line. In the improved model, the striking distances to phase conductors, shielding wires and ground are differentiated. Furthermore, the influences of ground obliquity, wind deflection and operating voltage of phase conductors are taken into account. The proposed improved EGM is applied to calculate the lightning shielding failure rate of a UHVAC transmission line to be built in a demonstration project in China. The simulation results show that the maximal difference of shielding failure rates due to the phase angle of conductor voltage in a period can reach 0.16 times/100km-year. The shielding failure rate accelerates with the increase of the ground obliquity and the wind speed. The shielding failure rate of the transmission line with ZBS2 tower is free of shielding failure outage in the investigated range. However, the shielding failure rate of the transmission line with ZMP2 tower is less than the tolerable limit of 0.1 times/100km-year only if the ground obliquity is smaller than 10°.
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Received: 28 August 2007
Published: 14 February 2014
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[1] 中国电力工程顾问集团公司. 交流特高压试验示范工程, 6卷, 第七册: 防雷保护研究, 2006.
[2] Golde R H. The lightning conductor[J]. Journal of The Franklin Institute, 1967, 283(6): 451-463.
[3] Young F S, Clayton J M, Hileman A R. Shielding of transmission lines[J]. IEEE Transactions on Power Apparatus and Systems, 1963, S82: 132-154.
[4] Brown G W, Whitehead E R. Field and analytical studies of transmission lines(Part Ⅱ)[J]. IEEE Tran- sactions on Power Apparatus and Systems, 1969, 88(5): 617-626.
[5] Brown G W, Whitehead E R. Field and analytical studies of transmission lines[J]. IEEE Trans. on Power Apparatus and Systems, 1968, 87(1): 270-281.
[6] Sargent M. The frequency distribution of current magnitudes of lightning strokes to tall structures[J]. IEEE Transactions on Power Apparatus and Systems, 1972, 91(5): 2224-2229.
[7] Eriksson A J. An improved electrogeometric model for transmission line shielding analysis[J]. IEEE Transactions on Power Delivery, 1987, 2(3): 871-886.
[8] 朱木美. 架空地线的保护范围及绕击率的计算[J]. 华中工学院学报, 1965, 5(8): 1-14.
[9] IEEE Std 1243-1997, IEEE guide for improving the lightning performance of transmission lines[S].
[10] 解广润. 电力系统过电压[M]. 北京：水利电力出版社, 1985.
[11] 陈国庆. 计及风速影响的500kV同杆双回线路绕击耐雷性能计算模型研究[J]. 中国电机工程学报, 2003, 23(5): 108-115.
[12] Holt R, Nguyen T T. Determination of optimal shielding angles in shielded transmission line design[C]. Proceeding of IEEE Power Engineering Society Winter Meeting (Singapore), 2000, 4: 2892- 2897.
[13] 李晓岚. 击距系数及基于电气几何模型的输电线路绕击跳闸率计算的研究[D]. 武汉：华中科技大学, 2005. |
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2009, Vol. 24 
