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Projects: Projects for Investigator
Reference Number NIA2_NGESO023
Title Inertia Measurement Method Optimisation
Status Started
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 ESO
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 September 2022
End Date 30 September 2024
Duration ENA months
Total Grant Value £371,000
Industrial Sectors Power
Region London
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , National Grid ESO (100.000%)
  Industrial Collaborator Project Contact , National Grid plc (0.000%)
Project Contact , SP Energy Networks (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA2_NGESO023
Objectives Work Package 1: Analysis and comparison of inertia measurements from commercial systemsIn this WP, data from commercial systems continuously collected over periods of months/year will be analysed and compared. Data will also be compared with the calculated inertia derived from the inertia contribution of the synchronous generators connected at each period. In addition to this, correlation to known influencing factors on inertia will be analysed, including generation and demand scenarios.For data from the commercial systems, at least one system provides standard-deviation based confidence data and this will be used to calculate the type-A measurement uncertainty. Other information will also be used, such as data error flags to reject data from the comparison and manufacturers accuracy specification data.In comparing the results, the combined estimated uncertainty from all the systems will be used as a bench-mark expectation of agreement from which to judge whether the systems agree at a given period.Deliverables: Presentation review of interim results from WP1, and final report on the results of WP1.Work Package 2: Assess regional differences in frequency and RoCoF for GB systemsThis WP is a calculation and modelling based activity which will determine expected differences in the values of frequency and RoCoF for different areas of the GB grid and assess the suitability of different regional inertia representations.The sensitivity of the model output to changes in assumptions and variations of the inputs will be assessed to estimate the uncertainty of the model outputs. Deliverables: Presentation review of interim results. Final report on the results of WP2.Work Package 3: Development of reference frameworkAt the present there is no reference standard for inertia, it is an operationalist measurement and validity of this measurement must be assessed as a metric in the context of the given use case.Using the outputs of WP1 and WP2, and knowledge of the operational scenarios of the power system, a set of use-cases will be developed along with a standard set of power system frequency characteristics representative of common power system inertia measurement scenarios. These characteristics will be used to develop and test inertia measurement methods and instruments.Frequency and RoCoF algorithms will be adapted and developed to account for the influencing factors such as system noise, voltage modulation (flicker), phase steps and low frequency inter-harmonics. Testing and assessment of the algorithms against various influencing factors for given use cases will be made to ascribe an accuracy to each measurement scenario.Deliverables: Document proposing a reference framework for inertia measurement including test cases and methods. This document and deliverable 4 will be sent or presented to standards committee IEC TC8 JWG8.Work Package 4: Development of reference instrumentThis WP will implement algorithms in software to run in real time on existing NPL PMU instruments. The instrument (hardware and software) will be calibrated against national standards of AC voltage and current, and a measurement uncertainty will be estimated.The consequences of imperfections in the instrumentation for the measurement of frequency and RoCoF will be assessed in the context of the waveforms expected in each use case.Deliverables: Document providing technical specifications for reference instrument. Exploitation plan for reference methods and instrument developed in WP3 and WP4, respectively.Work Package 5: Comparison with NPL reference instrumentsThe final WP will install 3-6 NPL PMUs in the power grid at selected locations in parallel to NGESOs frequency and RoCoF measurement systems for 6-12 months. A comparison between commercial RoCoF measurements and the reference instruments will be made, including during abnormal events on the power system.The uncertainty of the reference instrument will be known from WP4, and taking into account the statistical data from the on-site measurement, an uncertainty can be calculated for each measurement and combined with the statistical (and other) uncertainties of the commercial system to give a combined uncertainty as an expectation for the comparison.If there is a reason these PMUs cannot be installed, an alternative option is to use NPL laboratory testing of NG frequency and RoCoF instruments.Deliverables: Review meeting with presentation of interim measurement and validation results. Final report on the results of WP5. Test protocol for on-site verification of inertia measurement systems.In line with the ENAs ENIP document, the risk rating is scored Low.TRL Steps = 2 (3 TRL steps)Cost = 1 (£371k)Suppliers = 1 (1 supplier)Data Assumptions = 2Total = 6 (Low) Understand the accuracy of the inertia monitoring systems and dependencies on different generation / demand profiles.Understand regional differences of inertia.Establish standardisation methodology for measuring inertia and RoCoF.Clarity on accuracy of inertia measurement will feed into specification for inertia products with both Control and planning timescales. Using the metering data from the two new inertia system tools developed following earlier innovation and IT projects, along with the existing NGESO inertia “estimate” and operational data, the project will:Analyse and verify the quality of the data from these new tools through comparisons to the existing NGESO estimation.Establish different scenarios / use cases for inertia and RoCoF, for example based around levels of synchronous and renewable generation and demand.Compare the different solutions based on the established use cases.Identify regional inertia variations and representations.Develop measurement parameters and specification for reference instrumentation.Build on data and use cases to establish standardisation for inertia measurement by comparing measured results to modelling.
Abstract Changing generation is resulting in lower system inertia and increasing costs, with residual inertia making up a larger percentage of the total system inertia. The ability to measure real-time inertia will enable both synchronous and residual inertia to be known, improving decision making and reducing the risk of the system running insecure. There is currently no best practice or standardisation for measuring system inertia. This project will analyse and verify data from new commercial inertia monitoring tools and compare to NGESO operational data, establishing different generation and demand scenarios for inertia and Rate of Change of Frequency (RoCoF). Through development of measurement parameters and specifications for reference instrumentation, the project will build on existing data and use cases with the goal to establish standardisation for inertia measurement.
Publications (none)
Final Report (none)
Added to Database 14/10/22