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Projects: Projects for Investigator
Reference Number NIA_SHET_0025
Title Zero Missing Phenomenon
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
Scottish and Southern Energy plc
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 October 2018
End Date 01 June 2020
Duration ENA months
Total Grant Value £128,500
Industrial Sectors Power
Region Scotland
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , Scottish and Southern Energy plc (100.000%)
  Industrial Collaborator Project Contact , Scottish and Southern Energy plc (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA_SHET_0025
Objectives This project proposes a technical method that will involve engaging consultants to investigate the ZMP and produce conclusions that can impact the future of circuit breaker design. The investigations will focus on understanding the decaying DC current phenomenon produced through the use of shunt reactors, potential consequences and risks, and the ability of existing equipment to interrupt it. It will also outline any potential mitigation options and test their efficacy through network studies. The planning, training, operation and maintenance requirements of any viable mitigation options will also be established. This information can be used by network companies with similar installations. This problem has not been previously investigated in detail. The shunt reactor DC current problem can pose significant risk to equipment and nearby personnel and merits further investigation. This project focuses on investigating the decaying DC current problem. It is a feasibility study only, with its conclusions intended to further collective understanding of the problem while assessing the viability of mitigation strategies and technologies. Future projects can use this information to decide if live trials are suitable.The following steps will form the methodology of the investigation: A thorough literature review to identify previous work in this and similar areas. This will include an overview of the ability of circuit breakers and different circuit breaker technologies to interrupt decaying DC currents. Shunt reactor installations on the SPT and SHE Transmission Network will be grouped into a number of typical representative cases. For each representative case, simulations shall be carried out to understand and quantify the reactor DC current problem, its impact and associated risks. OEMs will be engaged to establish the capability of available equipment and circuit breaker technologies to interrupt prospective DC currents. The likelihood of the problem occurring, the associated risks and mitigation options will be evaluated, and their efficacy tested through further network studies. Operational guidance will be developed, and recommendations formulated for future implementation in network companies.A progress report will be produced upon the completion of each step outlining the results and findings. An investigation into the ZMP DC current problem in detail (cause, consequences and likelihood). An investigation into the capability of circuit breakers to interrupt the prospective fault current An investigation into mitigation options and strategies (and developing them) Risk analysis of any viable mitigation options and strategies Establish the planning, training, operation and maintenance requirements of any viable mitigation options Compile reports with results of the study for dissemination and to decide the viability of live trials of the mitigation options
Abstract The efficient running of high voltage Alternating Current (AC) networks involves, among other things, the management of reactive power flows. Transmission lines and cables tend to generate reactive power which requires to be compensated for to manage voltage profiles and reduce energy losses on the system. During periods of low loading, the voltage on a long transmission line or cable may increase along the circuit with the potential to fall outside the operational limits and equipment voltage design ratings which could result in equipment failure. One effective way to manage system voltages within desired operational limits is the use of shunt reactors where the system is susceptible to high voltages. The transmission networks in GB have several installations with shunt reactors connected in different configurations including, but not limited to, line connected, busbar connected and auto-transformer tertiary connected to manage system voltages.

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Added to Database 15/12/22