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Projects: Projects for Investigator
Reference Number NIA_NGET0165
Title Transformer Rating Modelling Tool Enhancement
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 PHYSICAL SCIENCES AND MATHEMATICS (Physics) 50%;
ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 50%;
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 2015
End Date 01 May 2017
Duration 20 months
Total Grant Value £500,000
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_NGET0165
Objectives In keeping with the innovation strategy for enhancing capacity, we have identified the opportunity to significantly improve the existing transformer thermal rating tool through the development of new modelling algorithms, all of which will future proof TRALC as well as improve the overall capability. Enhancements will be made to associated tools which feed into TRALC; the TEFLOW thermal-hydraulic network modelling program and a feasibility study on linking condition to capability. The research, development and trial of TRALC3 and the TEFLOW user interface, as well as a set of recommendations identified on the value of linking Condition to Capability to TRALC3. Completion of the scope of deliverables across the three correlated areas of development for this project: Numerical library completed, updated TRALC specification, client application developed Model enhancements integrated, test case development for TRALC3 UAT, report on feasibility study for linking condition to capability for transformers, server framework application completedTRALC3 deployment and User GuideTEFLOW User Guide and deploymentCompletion of bug fixes
Abstract The ability to harness thermal capacity of electrical equipment under emergency conditions is essential for the operation of the Transmission system. This approach enables critical system access for maintenance and construction activity and saves £millions of constraint costs each year. The enhanced rating modelling tool for transformers, TRALC2 (TRAnsformer Loading Code), was developed nearly 20 years ago. TRALC2, and the models that underpin the tool, is still used on a regular basis to provide enhanced rating advice to GB System Operator for transformers. NGET has identified an opportunity to make significant improvements to the underlying models, which go beyond the capabilities of commercially available transformer rating models. Once thoroughly validated to be able to be implemented into business as usual operations in National Grid, these improvements and the innovation of new models will increase the resilience of the tool to future changes and make it more accessible to other systems as they are produced. The innovative models that will underpin the new TRALC3 tool will provide a solid base for further developments as they arise - better estimations on thermal distributions and changes in equipment design, changes in the approach to static ratings to confront the issues of rising ambient temperatures owing to climate change and greater availability of monitoring technology and availability of data. In addition to development of TRALC3, two other innovation pieces of work will be carried out into transformer thermal ratings: TEFLOW is a thermal-hydraulic network modelling (THNM) program for transformer windings. It calculates a large range of physical parameters relating to heat transfer and fluid flow and these are saved for later analysis. It is a dynamic modelling program that enables the behaviour of winding temperatures and time constants to be studied under variable load and oil flow conditions. The graphical user interface (GUI) for the existing TEFLOW program has reached its end of life. It is no longer supportable and will not run on 64-bit versions of Microsoft Windows. In addition to updating the graphical user interface a guide will be produced so that TEFLOW can be used relatively easily to produce input parameters for TRALC3 for specific transformer designs, rather than using default parameters from IEC standards. It will also be used to support the thermal modelling work within another NIA project (NIA_NGET0088 - Transformer Consortium Research) by validating the results of the thermal calculations using an alternative technique. In conducting enhanced rating calculations for transformers some assessment is carried out as to the potential increase in asset life consumption that may result in an overload situation. However, it is always assumed that every transformer is in an ‘as new’ condition when determining the overload capability. This may be an unrealistic assumption, especially if transformers are known to have wet solid insulation. A feasibility study is to be carried out in to the relationship between transformer condition and thermal capability with the longer term aim of generating condition factors that may be used in TRALC3. The ability to maximise utilisation of thermal capacity of assets in emergency situations is an important tool for the system operator in managing the network; this is primarily achieved through the use of static rating schedules for circuits and leads to significant benefits to the customer through the avoidance of constraint costs. Whilst the tool is used by the system operator, the scenario modelling using component models such as TRALC for transformers is necessarily owned, developed and maintained by the asset manager who needs to understand the condition and capability of assets, the risk to the asset of carrying out emergency overloads and the benefits of allowing them to do so. The benefits to the asset manager of agreeing to enhancements include the following: Work may go ahead that might otherwise be deferred Generator constraint costs can be reduced or eliminated Load-related transformer schemes may be deferred Demand at risk outages can be assessed and found to be more secure The need for changing load flows on the LV network may be reduced This project aims to maintain and improve National Grid’s capability to perform enhanced ratings evaluation of transformers to maximise utilisation of thermal capacity. In migrating the system to a platform which is more resilient to changes of operating systems the opportunity will be taken to update the base algorithms in line with international guidance, improve the usability of the software and increase the number of situations where it can be used. TRALC3 will be an entirely new product underpinned by a set of innovative new models, developed by Oxford Computer Consultants (OCC) with technical support from Southampton Dielectric Consultants (SDC). The requirements of a revised TRALC have been identified but there will need to be an initial phase of identifying the business requirements in detail. Based on the detailed requirements TRALC3 will build on the learning from earlier work to produce transformer thermal rating algorithms in the Circuit Thermal Monitor (CTM) module in the Energy Management System (IEMS) to produce a cloud-based "ratings as a service" tool on a secure server. These improvements will increase the resilience of the tool to future changes in platform and make it more accessible to other systems as they are developed. For example: The SAM initiative creates an innovative opportunity to provide transformer ratings as a web service in a platform independent way ("Ratings as a Service") getting rid of dependencies on platforms and creating one repository of ratings dataWith an update of the existing rating algorithms from IEC 60354 to IEC 60076/7 the model is brought into line with current international best practice. The circuit rating tool, CUP2, is also undergoing review and a new TRALC would be able to generate transformer ratings automatically Whilst National Grid is not currently looking to develop a dynamic ratings approach, research within the NIA project "RESNET" has identified that this could provide some mitigation of the impact of climate change on ratings. This development would mean that the transformer rating tool was already well positioned for dynamic ratings in the future Whilst there is no quantified method for taking into account the effect that deteriorated transformer condition might have on ratings, TRALC3 could be develop such that condition factors could be included once they have been developed The proposed solution can act as a design template for ratings of other asset types in the future. TEFLOW development and transfer to a new platform will be conducted by SDC and the feasibility study into the assessment of the impact of conditionon the thermal capability of transformers will be carried out over six-months by a Research Associate at Southampton University. Project meetings will involve all parties concerned to foster collaboration and innovation between the project partners.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