Updates & Events

In 2026 we are planning to undertake several tasks in P35.019, HVDC Lines, including those listed below:

• Update HVDC Electrical Effects Module in TLWorkstation: Based on the results and data obtained from the reduced-scale, full-scale, and operational line measurements, the existing algorithms used in the EPRI TLWorkstation software tool intend to be updated and the user interface improved.
• Update HVDC Transmission Line Reference Information: This task intends to update the Overhead Line specific HVDC reference documents which was previously published by EPRI in the early 1990’s. This document details the design characteristics of existing lines, and describes the testing conducted and results obtained in determining the corona and electric field characteristics of HVDC transmission lines.
• Update HVDC Line Design Guide: This task, updated each year collects relevant information on HVDC line designs from various completed HVDC research tasks. Topics will include design aspects pertinent to HVDC and will identify areas of design that are similar between dc and ac. The guide is updated each year with new information.
• Perform Live-Line Tool Testing: This task intends to test live-line tools under HVDC conditions. The plan is to investigate the effects of space charge and corona to determine their impact on the flashover performance and voltage distribution along the length of the tool. Work might also be done to determine the accuracy of voltage detection devices under HVDC conditions.
• Evaluate Insulator Dimensioning for Contaminated Environments: Contamination is the main driver for insulation coordination of HVDC lines. Contamination performance of DC is vastly different from AC. This task intends to determine the latest state of the science in HVDC insulator dimensioning for contaminated environments. Testing and long-term aging of insulator materials may also be carried out.
• Update HVDC Reference Book (The Olive Book): An electronic version of the updated HVDC reference book will be made available to project funders. This reference book, updated each year, contains information on overhead lines and converter stations.
• Perform Hardware and Insulator Corona Tests: When specifying corona requirements for HVDC insulator hardware assemblies, many utilities use the equivalent peak ac voltage for testing. Currently, no HVDC hardware corona test specifications exist. This task intends to develop test specifications based on laboratory testing and develop guidelines to assist in specifying corona tests for HVDC hardware. In 2026 the intent is to review numerical simulations and to update the testing protocols.

2026 Engagement Opportunities

2026 Anticipated Deliverables

2025 Engagement Opportunities

2025 Deliverables