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Projects: Projects for Investigator
Reference Number NIA_NGET0185
Title Investigation of transient and safety issues in gas insulated systems
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 October 2016
End Date 01 April 2021
Duration 54 months
Total Grant Value £281,430
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_NGET0185
Objectives This research and development programme aims to achieve the following main objectives: Completion of an extensive review of available literature on state of the art of GIS discharge phenomena and earthing approaches. Develop suitable models of the GIS components and system to determine electric field and fast transient surge levels. Furthermore, develop procedures to reduce the magnitude and other effects of such surges. Develop models of the earthing system to allow accurate determination of rise of earth potentials, and develop mitigation techniques to ensure safety of GIS earthing system. Develop measurement techniques to allow comparison with modelling, improve understanding and allow future monitoring of the above phenomena in GIS. Develop mitigation measures for fast surges and rise of earth potential. The delivery of a successful innovation project is reliant on a number of deliverables to be achieved at the end of the project period. Comprising of the conclusion of a state-of-art review; provision of parametric modelling of switching operations in GIS; a quantification of the earth potential rises in GIS and the production of possible mitigation measures with recommendations; and the validation and verification of theoretical conclusions of the measurement techniques.
Abstract Gas insulated substations (GIS) offer significant benefits, including savings in substation footprint and their operation is not affected by weather conditions. However, because the voltage breakdown in SF6 is fast compared to air, many switching operations could result in very fast transient phenomenon being generated and propagated not only in the high voltage conductor systems but also in the ‘earthed’ enclosures. The academic understanding of fast transient phenomena is not yet readily explored and acknowledged by network operators, which could lead to the situations where earthing and bonding arrangements are not optimally designed and/or installed at the project construction phase. The population of GIS equipment on the network is growing quickly; this is in large part due to the many benefits that GIS presents. Gradual but steady changes to the electricity generation mix, and topology of the whole GB network, has meant the system operator is requesting operations of GIS with increasing frequency to achieve operational targets, such as voltage control and load flow control. An increase in operations will result in more occurrences of fast transient phenomena in GIS, which not only impacts the system operator but will impact on the maintenance activity undertaken by the transmission owner. Therefore, the appropriate and timely implementation of the findings from this research project will have a direct benefit to the GIS population as it continues to be subject to increasing stress. The aim is to mitigate any increasing stress and the resulting equipment faults and cost implications to the business and the industry a whole. This research project will address the need to carry out targeted studies to fully understand the major factors involved and how they impact on the magnitude of the fast transients in GIS. Equipped with the above knowledge, GIS asset owners could produce better specifications for future GIS equipment. As well as optimising operations to mitigate potential faults and failures. This project will involve the study of GIS to gain in-depth understanding of phenomena appearing in gas insulated systems. These will include discharge activity, transient overvoltages during disconnect or switching, and line closing when connecting to overhead line circuits. Furthermore, earthing scenarios will be investigated to determine the need and requirements for high frequency earthing in such systems. Safety aspects of such configurations will be evaluated. The models generated within the modelling and simulation task will be compared and verified with controlled experiments and on site testing. For the purpose of advanced measurements, new fast voltage transducers will be designed, built and tested to allow measurement of the fast transient overvoltages. The method of research will focus on lab based modelling and measurement tasks undertaken by the students: Build both generic and specific installation models for electric field, transient and earthing investigations, Design and build transducers to test the measurement of transient overvoltages and earth potential rise in GIS during switching operations, Identify the phenomena occurring in GIS, and therefore the contributing factors to rapid voltage breakdown in SF6Establish procedures and solutions to mitigate fast surges and rise of earth potential in GIS during switching operations.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 31/08/18