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Projects: Projects for Investigator
Reference Number NIA2_NGET0028
Title Identification and quantification of C4F7N gas arcing by-products and their implication for GIS operation
Status Started
Energy Categories Other Power and Storage Technologies(Electricity transmission and distribution) 100%;
Research Types Applied Research and Development 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Project Contact
No email address given
National Grid Electricity Transmission
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 November 2022
End Date 31 March 2026
Duration ENA months
Total Grant Value £1,770,000
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , National Grid Electricity Transmission (100.000%)
Web Site https://smarter.energynetworks.org/projects/NIA2_NGET0028
Objectives "This project seeks to identify and quantify the by-products created from C4F7N gas mixtures, in particular, a mixture with carbon dioxide and oxygen. The gas mixture will be subjected to both AC and impulse energisations of various degrees of severity. Conditions within the gas, such as pressure and moisture will be investigated.The work will be laboratory based with a new set up being developed for the purposes of the project. Analysis and monitoring techniques will be explored early in the project, techniques such as high-speed spectrometry/spectroscopy, fast pressure sensors and Schlieren photography will be explored to obtain data. Using such laboratory techniques could help simpler, more practical sensors for in-service field deployment.An additional test cell will be designed and constructed for investigating the interaction of the gas mixture under high voltage/current conditions with materials typically used in the manufacture of high voltage equipment.Data Quality Statement (DQS):The project will be delivered under the NIA framework in line with OFGEM, ENA and NGGT / NGET internal policy. Data produced as part of this project will be subject to quality assurance to ensure that the information produced with each deliverable is accurate to the best of our knowledge and sources of information are appropriately documented. All deliverables and project outputs will be stored on our internal Sharepoint platform ensuring access control, backup and version management. Relevant project documentation and reports will also be made available on the ENA Smarter Networks Portal and dissemination material will be shared with the relevant stakeholders. Measurement Quality Statement (MQS): The methodology used in this project will be subject to our suppliers own quality assurance regime. Quality assurance processes and the source of data, measurement processes and equipment as well as data processing will be clearly documented and verifiable. The measurements, designs and economic assessments will also be clearly documented in the relevant deliverables and final project report and will be made available for review.Risk AssessmentTRL Steps = 2Cost = 3Suppliers = 1Data Assumption = 1Assessed risk score 7 – Medium" "The project will be delivered in the following six workstreams through which the resulting by-products from electrical testing will be identified, quantified and assessed for their potential health impacts, their reactivity with other materials and the prospect that they may be use as diagnostic markers for asset health:WS1: Quantification of arcing by-products under credible fault scenarios in switchgear using commercial C4F7N mixturesWS2: Arcing by-products: effect of moisture ingress, pressure, air on their concentration and rate of productionWS3: Reaction with other materials: effect of combined temperature and electric fieldWS4: Materials compatibility with presence of by-productsWS5: SHE and legislative complianceWS6: Feasibility of by-products monitoring for fault diagnostics, equipment condition, remaining life of C4F7N gas mixture -filled equipment" "This project will deliver greater understanding of the performance of C4F7N gas mixtures in operational conditions ahead of widespread use in switchgear. Specifically, the following objectives are planned:Identification of by-products that may require specific handling precautions in arced gas mixtures and the guidance needed for handling themUnderstand the impact of different service conditions on nature of by-productsInvestigate the potential for specific by-products to be used in monitoring asset health of in-service equipment."
Abstract This project aims to develop underpinning knowledge on the characteristics of C4F7N gas mixtures, which may be used as alternatives to SF6, with a specific focus on the long-term gas stability to demonstrate performance in service in new equipment. It will consider credible in-service scenarios where the gas may be put under stress that could lead to changes in the chemical make-up of the gas mixture, including any changes that could result from interaction with materials used in the manufacture of the equipment and low levels of moisture and air contamination. The resulting by-products will be assessed for their potential health impacts, their reactivity with other materials and the prospect that they may be use as diagnostic markers for asset health.
Publications (none)
Final Report (none)
Added to Database 12/10/23