SF6 GAS ALTERNATIVES, GAS HANDLING, MIXING AND SAFETY
This month’s Featured Technical Paper is from the Proceedings of the 2024 International Conference of Doble Clients. The paper is titled: SF6 Gas Alternatives, Gas Handling, Mixing and Safety.
Abstract
As technology improvements are being introduced, guided by changes to environmental regulations that aim to reduce greenhouse gas emissions, users of Gas Insulated Equipment (GIE) are looking to reduce the dependency of sulfur hexafluoride (SF6) in their fleet. In some cases, users are researching how to eliminate the use of SF6 gas for GIE with higher voltage ranges (>245kV, 33kA and/or >63kA). These voltage and current ratings require alternative solutions that provide arc quenching as well as dielectric insulation with efficiency that meets or exceeds the current technology of SF6 gas. New technology such as, C4-Fluoronitrile (C4F7N (here forward referred to as C4F4) is currently the closest technology available that considers footprint, arc quenching and insulation at the higher voltages described above.
Solutions such as synthetic air and natural origin gases (NOG) have also become commercially available as an alternative solution for switchgear up to <145kV 63kA. While there are already commercially available solutions for SF6 gas alternatives, Original Equipment Manufacturers (OEM’s) are working towards applying their insulating gas technologies for higher voltages. The table below provides a road map of these technologies versus the current CA Air Resources Board & European Union (EU) timeline to ban/reduce SF6 gas.
Alternative insulating gas technology such as C4F4, synthetic air and NOG require specific mixing and handling procedures. This document will focus on differences in the handling of the liquid and vapor gases, which are in part or in whole used to create insulating gas mixtures, specifically for the application in medium voltage and high voltage gas insulated equipment. It will also advise on how to identify the correct ratio of components in the mixture (gases), prevent cross-contamination during gas mixing, and maintain a homogenized gas mixture where applicable. Similarities and differences between SF6 gas and alternative gas handling will also be discussed.
In addition to the mixing processes, safety and handling considerations, and analysis of the mixtures, will be discussed as they are a crucial part of the assessment for use in GIE.
Doble Service Agreement Clients
This and other technical papers and presentations are available in MyDoble - one of the many benefits available to you as a Doble Service Agreement Client. To get a MyDoble login click here. Not a member? Follow the sign-up process.