Transient Simulations and Analysis of Overvoltage Insulation Coordination of Extra High Voltage Transmission Lines
Authors: Aibangbee, J.O. And Ikheloa, S.O.
DOI Info: http://doi.org/10.5281/zenodo.12599502
ABSTRACT
Insulation coordination of extra high voltage is a designing criterion for transmission lines such that it minimizes interruptions during steady state conditions as well as minimizes damages in case of transient over voltages. In order to prevent Lightning overvoltage strikes and its effects on transmission lines and towers from occurring and to understand the intensity of these effects these four major faults were simulated in Alternative Transient Program (ATP) EMTP software and its effects were observed and presented using the statistical method of insulation coordination to determine the transmission line insulation level, and lightning arresters. Four major case studies simulated include lightning over voltages strikes on: (a) shield wires alone; (b) shield wires with surge arrester; (c) red phase conductor; and (d) red phase conductor with surge arrester. The travelling waves propagate along the transmission lines was 3 x 108 mt/sec. A switching withstands voltage for transmission line insulation of Basic Impulse level (BIL) values of 1550 kV was selected; with associated rated lightning withstand voltage of 2300 kV. Lightning arrester rated 420 kV been the minimum rating was selected for the transmission lines. Result showed that maximum continuous over voltages (MCOV) and temporary overvoltages (TOV) determine the criteria for selecting adequate surge arrester voltage rating. It minimizes the arrester discharge voltage for any particular surge, thereby maximizing the protective margins.
Affiliations: Department of Electrical/Electronic Engineering, Benson Idahosa University, Benin City, Edo State, Nigeria.
Keywords: Extra High Voltage, Insulation Coordination, Transients, Basic Impulse Level, Lightning Arrester, Switching Surges, Lightning Strikes
Published date: 2024/06/30
