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Projects: Projects for Investigator
Reference Number NIA_NGET0143
Title Transient and Clearances in the Future Electrical Transmission Systems (ICASE Award)
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 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 September 2012
End Date 01 June 2016
Duration 45 months
Total Grant Value £171,000
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , National Grid Electricity Transmission (100.000%)
Web Site http://www.smarternetworks.org/project/NIA_NGET0143
Objectives The objectives of the project include: A review of the following areas to produce an overview of the current ‘state of the art’ and the areas with the highest priority for further work: The existing insulation coordination methodology within National Grid The historical background behind the definition of the existing safety clearances and the guidance of standardisation bodies such as IEC and CIGRE in this area The differing clearance requirements for standard substation working and live line working The different methodologies employed across global transmission systems to manage overvoltage levels The impact of new technologies on overvoltage levels A review of the capabilities offered by modern simulation packages (to include EMTP, EMTDC and Digsilent) to make a recommendation on which is best suited to carry out insulation coordination studies as judged on the basis of technical capability and ease of integration with existing National Grid models. The development of a simplified National Grid system model capable of being used for a range of overvoltage studies within the chosen simulation package. This model should represent a section of the actual transmission system and have the capability to include new technologies (the connection of offshore HVDC for example). The success criteria of the project will be The delivery of a report that critically examines the safety clearances applied to the high voltage system and those which are applied in the case of live line working both on overhead lines and within substations. A model of part of the National Grid system delivered in such a way that electromagnetic transient studies can be quickly / easily run by National Grid staff in the future A report highlighting the opportunities and/or threats that could be derived from a modification to the existing insulation coordination methodology within National Grid including a change to the overvoltage levels stated in technical specifications and the use of different forms of protective devices
Abstract With the move to new transmission system technologies and the possible use of live line working on both overhead lines and substations, it is timely and important to review the magnitude and frequency of transients. Of particular importance are switching transients that in the majority of cases drive the need for safety clearances and have an impact on the reliability of the equipment used on the network. Previous work reviewing the magnitudes of over voltages observed on a simple overhead line circuit have demonstrated the need for clearances higher than those previously used and above the level typically stated as safety clearances. Operating experience would, however, suggest that the existing safety clearances are adequate. To develop appropriate clearance standards, National Grid will benchmark other standardisation bodies and assess existing guidelines to produce an overview of the current ‘state of the art’ being adopted throughout the industry. To support this, an assessment of the modern simulation packages available will identify the best suited to carrying out insulation co-ordination studies based on technical capability and ease of integration with existing National Grid models. The findings from these studies will influence the development of a simplified National Grid model capable of being used for a range of overvoltage studies within a chosen simulation package.Note : Project Documents may be available via the ENA Smarter Networks Portal using the Website link above
Publications (none)
Final Report (none)
Added to Database 17/12/18