Factors Affecting Ground Potential Rise and Fault Currents Along Transmission Lines With Multigrounded Shield Wires

Abstract

The multigrounded shield wire transmission scheme is common within North American utilities. The ground potential rise (GPR) for this transmission scheme is important as it is to be used to develop specifications for systems and component protection. No hand calculation methods for GPR for high-voltage transmission line faults exist due to the complexity of the problem itself and vast amount of data input required. Such calculation depends only on computer simulation software, and very limited information has been reported in the literature. This paper aims to provide insights into GPR for high-voltage transmission line faults by demonstrating quantity values for the very first time through extensive computer simulation using the ATP-EMTP software. A practical design for a 160 km 230 kV single-circuit transmission line with two multigrounded shield wires is used as a case study in the paper. Different factors affecting GPR and fault current levels in the system are investigated through a sensitivity study. The underlying relationship between parameters is analyzed and summarized based on simulation results, which can be used to assist practicing engineers’ design work.