Induced Pipeline Voltage Near-by Hybrid Transmission Lines

Abstract

The aim of this paper is to calculate the induced voltage, nearby hybrid transmission lines. Two hybrid transmission lines are simulated and modeled. The first line is double-circuit operating with ac voltage of 220 kV and bipolar circuit with a dc voltage of ±500 kV, while the second line is with flat configuration operating at 500 kV ac and of ±500 kV. The induced voltage on the pipeline is calculated due the mutual effect of the electric field of these lines. The charge simulation technique and COMSOL computer package are used for calculating the electric field underneath the hybrid lines with and without pipelines and are used to determine the induced voltage on the pipelines.

The maximum induced voltage is 9.5 kV for the first line at spacing (S) of 10 m and DC circuit height of 15.7 m against 4.3 kV for height of 24.9 m. The corresponding values for the second line at the same spacing S of 10 m are 7.08 and 3.1 kV for DC circuit heights of 19.1 m and 30 m respectively. The maximum induced voltage on the pipeline is slightly changed due to changing the phase sequence of the AC circuit and the spacing between AC and DC circuits.

Keywords: Induced Voltage, – Electric Fields, HVDC Transmission, Finite Element Method, Hybrid Transmission Lines.