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Projects: Projects for Investigator
Reference Number NIA_NGTO042
Title Impact of System inertia on the Critical Clearance Times (CCT) on the GB Transmission Network
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 January 2020
End Date 31 July 2021
Duration ENA months
Total Grant Value £175,000
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , National Grid Electricity Transmission (100.000%)
  Industrial Collaborator Project Contact , National Grid Electricity Transmission (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA_NGTO042
Objectives The project will be carried out in a staged approach. Firstly, a comprehensive inertia evaluation methodology will be developed. It will consider all the key ineria contributing components. The system inertia will be assessed nationally and regionally and the metholodolgy will be validated against past frequency events on the GB network.In the second stage of the project the relationship between system inertia and the CCT will be examined. This will be done by using simplified equivalent network models. Based on the learning from the work in the second stage, the impact of the declining system inertia on the CCT of regional and GB national transmission netwok will be investigated. Work Package (WP) 1 – System Inertia EvaluationIn this work package (WP 1) a new method will be developed for calculating system inertia by analysing the contributions from different sources. This will include the key inertia contributing components that have not been analysed in the past (e.g. renewables within transmission system as well as demand (motors) from distribution networks). The detailed inertia for the regional and the GB national network will be evaluated using the method and validated against past frequency events on the GB network.Work Package (WP) 2 – Impact analysis of system inertia on the CCTWP 2 will establish the relationship between the inertia and the CCT. This will include building a simplified network model by incorprating various system inertia scenarios (e.g. different renewable penetration levels) from the NGET network for the analysis. A methodology will also be proposed to validate the model.Work Package 3 – Evaluation of the impacts of system inertia on the CCT of the GB networkThis package will evaluate the impacts of system inertia on the CCT in the GB network by using the mothodology developed in WP2 and the system inertia data delivered by WP1. How regional and national CCTs are affected by the declining inertia will be examined. The visualisation of the impacts of system inertia changes on CCT will be demonstrated in this package. The main objective of the project is to assess the impact of the reduction of system inertia on the CCT of the GB transmission network to ensure sytem stability during the transition to net-zero carbone future. The project also aims to provide visualization of the system intertia impacts on the CCT in the GB network, and recommended future work to mitigate any potential instability risk.
Abstract As the nation is moving towards to a Net-Zero carbone future, system inertia is expected to continue declining. System inertia is closely related to the stability of the electricity network. The declining system inertia may expose the network to a higher risk of system instability. The capability of the protection system to clear faults in sufficient time is critically important to prevent system instability. This project aims to investigate how the future reduction of system inertia will affect the critical fault clearance time required in the GB network to ensure system stability.
Publications (none)
Final Report (none)
Added to Database 02/11/22