Characterization of Local Environmental Data and Lightning-Caused Outages in the IECo Transmission-Line Network

Abstract

The lightning-related outages remain a significant factor affecting OHL reliability in the IECo (Israel Electric Co) Power Grid 170-kV. The estimates derived for years 2000-2013 show that the actual failure rate for some lines does considerably exceed the accepted indices. The paper reports on the lightning study whose primary goal was to examine a relevant environmental data, including Topography, Tower Footing Resistance, and Lightning Incidence records provided by IECo Lightning Location System. The paper presents long-term monitoring experience and local statistical data patterns gained for Cloud-to-Ground Return Strokes. The 295 outage related flashes (265 of negative and 30 of positive polarity) were identified in the IECo database. The median peak current of the negative and positive flashes causing line outages is -12.0 kA and +26 kA, respectively. The local tower footing resistances are found to be lognormal distributed with a median of 4.77  and a SD of 1.44. The findings imply that revealed failure currents statistics, in combination with local route topography, are key factors controlling shielding performance of IECo lines. The acquired data will be involved in the further case studies on IECo lines. Index Terms--Lightning Location System (LLS), Cloud-toGround (CG) Return Stroke, Ground Flash Density (GFD), Shielding Flashover Failure Rate (SFFR), Back-Flashover Failure Rate (BFR), Electro-Geometric Model (EGM). 0885-8977 (c)

Evaluation of the Direct-Stroke Shielding Performance of Substations Through Stochastic Modeling of Lightning Attachment

“…L IGHTNING strikes impose a high risk of power system outages [1], [2], [3]. Substations, critical part of a power system, shall operate with high reliability and experience a practically zero outage rate [4].…”

Identify Direct Lightning Strike Location Based on Discrete Wavelet Transform for 115-kV Transmission System

“…According to the study focused on a characteristic [10][11][12][13][14][15][16][17][18][19][20][21][22], lightning signals included return strikes, channel of current [10], upward lightning, potential lightning [11][12], velocity and etc. were considered.…”

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