Influence of transmission line tower grounding impedance to the line flashover rate

Abstract

The paper presents a mathematical model for analysing impulse characteristics of complex grounding grids in uniform and two‐layer soil. The model is based on the grounding grid equivalent circuit with lumped parameters, described by a system of differential equations. The effect of the mutual couplings of the grounding grid elements can be comprised by the so‐formed model. The established model has been successfully checked experimentally for the square grounding grid. A grapho‐analytical approach to the evaluation of the transmission line tower impulse grounding impedance model is described. The proposed model is convenient for practical application. It is incorporated into the present lightning overvoltage computation program. The methodology of the line flashover rate estimation is illustrated at the example of 400‐kV overhead lines.

Some aspects of overhead transmission lines lightning performance estimation in engineering practice

“…Impulse tower grounding model based on elements with lumped parameters is suggested in [1], and influence of the similar model to the line flashover rate is discussed in [25]. Impulse tower grounding model based on elements with lumped parameters is suggested in [1], and influence of the similar model to the line flashover rate is discussed in [25].…”

“…where E 0 is soil ionization gradient, the recommended value 400 kV/m and ρ is the soil resistivity (Ωm). Impulse tower grounding model based on elements with lumped parameters is suggested in [1], and influence of the similar model to the line flashover rate is discussed in [25]. Brief analysis of the impulse grounding impedance based on the theory of electromagnetic fields is presented in [26], [27].…”

ATP-EMTP-Based Approach to Teaching Insulation Coordination in the Electrical Engineering Curriculum

“…For this reason, the grounding has been modelled by the parallel connection of components R 1 = 37 Ω and R 2 L, where R 2 = 6.68 Ω and L = 8.74 µH. 11 In Fig Overhead line span modelling -three-phase model Some overhead line spans were modelled by the LINE CABLE CONSTANTS (LCC) module. The JMARTI distributed-parameter line model, 3 which is a frequency-dependent model, has been selected.…”

Reconsidering insulation coordination and simulation under the effect of pollution due to climate change

“…In this paper, insulation coordination review and design has been conducted for 63, 230, and 400 KV transmission and overhead distribution lines. Power transmission and overhead distribution lines need 2 components: cables, which conduct electricity; and electrical insulators that keep cables away from steel towers or pylons . Insulators have been used since the appearance of electricity transmission lines.…”