Overview & Events

Lightning Arc Damage to OPGWs In recent years, utilities are increasingly experiencing damage to optical fiber ground wires (OPGWs) caused by lightning strikes to the ground wire. In some cases, severe damage to the OPGW could result in failure of the communication link or mechanical failure of the ground wire. In 2024, this task intends to review the sizing method of OPGW regarding lightning arc damage and the associated test protocols commonly used by utilities.

Shield Wire Insulation Performance Utilities use insulators on shield wires to control circulating currents and inductive power losses. When the shield wire is struck by lightning, the insulator can flash over, and if the arc is sustained, the insulator can be damaged. In 2024, this task intends to develop guidelines on applying shield wire insulators.

Transmission Line Surge Arrester Selection Non-gapped line arresters are often applied to improve the lightning performance of transmission lines and to control overvoltages. Their selection is not straightforward, and utilities typically rely on manufacturers for this. In 2024, this task intends to document the selection method using the recent updates of IEC and IEEE standards allowing for a more precise definition of the energy-handling capacity and to provide a tool to simplify the selection.

Educational Video on Lightning Attraction Models for Transmission Lines Under this task, a library of educational videos is being developed to enhance the technical understanding and competencies of utility personnel.
In 2024, this task intends to complement the series of educational videos on lightning performance by explaining how lightning interacts with a transmission line and how it is modeled to estimate the attraction of lightning strikes to phase conductors that can cause shielding failure flashovers.

Lightning and Grounding Reference Book EPRI has amassed a large knowledge base of lightning and grounding information. This task develops a single reference book that consolidates previous EPRI lightning and grounding research. The reference guide enables utilities to quickly find information, explanations, and tools for improving the outage performance of their overhead lines. Some of those tools are hosted on EPRI’s transmission.epri.com to help utilities compare technical solutions and to provide additional training materials. The reference book (available in electronic format) is updated with new information each year.

Transmission Line Workstation—Generation 2 (TLW-Gen2) Software: Lightning Performance and Power Frequency Grounding Modules New version of the Lightning Performance Analysis Module (TFlash). This is a software tool for determining the lightning performance of lines. This task intends to update the tool with the latest research results to improve and expand its modeling capabilities. Participants of this project get access to the Lightning Performance module of TLW-Gen2.
Updating the Power Frequency Grounding Module. This is a software tool for calculating fault current division and circulating currents on transmission line. This task intends to update the software to expand its capabilities. Participants of this project get access to the Power Frequency Grounding module of TLW-Gen2.