Evaluation of induced AC voltages in underground metallic pipeline

Purpose - The purpose of this paper is to make a study of electromagnetic interference between electrical power lines and nearby underground metallic pipelines. Design/methodology/approach - The equivalent electrical circuit of the studied electromagnetic interference problem between electrical power lines and nearby metallic pipelines is created and solved using a loop currents technique based on a hybrid method. The used circuit solving technique was implemented in a software application developed by the authors. Findings - The authors have identified the influence of phase sequence on induced voltage level in an underground pipeline for a double circuit electrical power line. Also the effect of different normal operation and phase to earth fault currents have been revealed. Practical implications - The study has been made through a research project with the Romanian gas transportation company, in order to find the proper protection techniques for underground metallic pipelines. Originality/value - The paper reveals the influence of some electrical and geometrical parameters that have not been studied in detail previously.