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Projects: Projects for Investigator
Reference Number NIA_NPG_030
Title Switchgear Enhanced Rating
Status Completed
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 Sociological economical and environmental impact of energy (Policy and regulation) 100%
Principal Investigator Project Contact
No email address given
Northern Powergrid
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 September 2018
End Date 01 September 2020
Duration ENA months
Total Grant Value £30,000
Industrial Sectors Power
Region Yorkshire & Humberside
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , Northern Powergrid (100.000%)
  Industrial Collaborator Project Contact , Northern Powergrid (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA_NPG_030
Objectives It is believed there is no currently published National/International Standards for this problem or simple tool for justifying the operation of switchgear at higher than normal rated current for short periods. The development of a methodology and calculator tool to assess what overload capacity, if any, a particular type of switchgear has, based on its temperature rise type test results, would be a novel solution. It is envisaged that switchgear, particularly older switchgear, installed on distribution networks could have a higher thermal capacity than the assigned rating which, if known, could be exploited for short-term overloading. The solution will ensure DNOs use a consistent and proven approach when applying temporary overloading to HV switchgear that is operating close to the rated values. The scope of the proposal is to produce a short-term overload rating methodology for common 11 kV and 33 kV switchgear used by the UK DNOs. It is anticipated that up to 5 types of commonly used primary HV switchgear and distribution switchgear would be reviewed in the project. A basic spreadsheet model will be developed that uses the thermal time constant from actual temperature rise type test results to calculate the thermal margin and to provide limits on what is, or what is not achievable for certain switchgear types involving the maximum rated load current that could flow safely. A guidance document that captures the methodology and how to use the spreadsheet model will be provided. The project consistes of four separate stages, each with a set of objectives.Stage 1 Objectives Data gather common types of HV switchgearCarry out desktop research to identify common HV switchgear that are suitable applying short term dynamic ratings (previous EATL STP projects have population counts that may be suitable). It is proposed to base the project on 5 primary types of switchgear and 5 secondary type switchgear. This will need prior agreement with ENA Member Companies. Review CIGRE and other appropriate reference material that may be referenced in the report in Stage 4.Stage 2 Objectives Gather temperature rise type test resultsGather temperature rise type test results, and data to allow thermal time constant to be calculated for the identified switchgear from the Original Equipment Manufacturer (OEM) or DNOs. Prepare the information ready to input into the model in Stage 3.Stage 3 Objectives Basic model buildBuild basic model in Microsoft Excel with easy to use front end and functionality to prevent incorrect entry and warnings. It is anticipated that the model will have a drop down selection for known types and will also allow the input of new equipment types. The model will show for how long and what load current may be applied.Stage 4 Objectives Report results and rules and guidance for operating modelProduce a Report, which will include guidance for using the model and will document the results for the types of switchgear selected and modelled in Stage 3. Reference will be made to appropriate CIGRE and other technical reports made available.
Abstract Switchgear Enhanced Rating
Publications (none)
Final Report (none)
Added to Database 14/12/22