Running Cool
| Funding mechanism | Network Innovation Allowance (NIA) |
|---|---|
| Duration | Jun 2022 - Mar 2024 |
| Project expenditure | £361K |
| Research area | Net Zero and the Energy System Transition |
| Regions |
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Objective(s)
This project will aim to integrate a short-term post-fault rating (derived from real-time conductor temperature measurements) into ANM systems in order to create a new post fault capability for OHLs. The key objectives of the projects are:
- To demonstrate what benefits can be realised by the application of OHL short-term post -fault ratings in ANM
To develop all required documentation to ensure safe integration of new capability into ANM.
Problem(s)
Full Active Network Management (ANM) systems are being implemented in areas where multiple complex constraints are affecting a number of customers over a long time period. A significant number of NGED ANM systems will curtail customers on a pre-cautionary basis under intact network conditions in anticipation of the next worst circuit fault to keep assets within defined ratings. This is partly because our overhead line (OHL) ratings are defined either as pre-fault or post-fault which do not permit an ANM system to wait for an event to happen and instruct generators to curtail. This ultimately means that curtailment is enacted even if an event doesn’t occur.
Pre-event curtailment strategies significantly increase the level of curtailment imposed on generation customers which can make a business case for some generation developers unviable. Under current regulatory arrangements we are not required to reinforce when an ANM area is being categorised as “full”. However, from 2023 it is expected that generators will not be required to directly cover the cost of deep reinforcement and this cost will be borne by NGED and, consequently, our customers. It will be our responsibility as a Distribution Network Operator (DNO) to ensure that there is sufficient generation capacity for all generation connection applications.
Method(s)
This project seeks to challenge current curtailment arrangements by creating a new post fault capability for overhead lines and a new ANM architecture which will help to avoid curtailment. An improved system of short term dynamic OHL ratings (informed by real-time conductor temperatures) and a new corresponding ANM control system architecture will be the key outputs of this work. This project will be delivered in five concurrently run stages as shown below:
Work Package One: Consideration of changes required to the ANM Control System Architecture
WP1 will review existing ANM scheme arrangements and will establish whether there are any planned upgrades to ANM systems and their timeframes. Once this step is successfully completed, WP1 will identify gaps in the existing ANM system arrangements and will map out changes required for ANM to support a new short-term post-fault ratings to supplement existing seasonal static ratings. Consideration will be given to failover arrangements of the ANM system if conductor temperature monitoring information becomes unavailable, for example, gracefully reverting to seasonal static post-fault ratings.
The output of WP1: will include a technical document outlining the functional changes required to the existing ANM system architecture .
Work Package Two: Short-term post-fault ratings and risk assessment
WP2 will build on the high-level technical implementation of a short-term post-fault rating delivered under OHL Power Pointer project. This approach will deliver a set of requirements (in a technical specification) for a short-term post-fault rating suitable for use in a live operational environment.
The output of WP2: will be an updated specification for the derivation of a short-term post-fault OHL rating. A risk assessment document specifying the risks of the application of short-term post-fault ratings and available risk mitigation measures which could be adopted.
Work Package Three: Development of Network Use Case and Power System Studies
WP3 will define representative network use cases comprising areas of the network. Network use cases will consider different conductor characteristics, mixed composition circuits (including underground and overhead cable sections), availability of the conductor temperature monitoring system, etc.
Power system studies utilising the network use cases will be undertaken to quantify the maximum capacity that can be released (in MWh) if the ratings derived from historic data are applied. It is proposed to carry out power systems studies to quantify the energy lost (MWh) due to full pre-event curtailment for the base case (current ANM scheme) by modelling the general profile of connected generation and checking the power flow constraints on circuit within the study area of the network. Where static seasonal ratings for conductors have been considered in the base case, these shall be substituted for short-term post-fault ratings captured under the OHL Power Pointer project for the method case, and the studies will be repeated.
The output of WP3: will be a technical report with a detailed description of network use cases and quantified benefits (in MWh) that can be realised by the application of short-term post-fault ratings within each of the use network cases.
Work Package Four: Finalised control system architecture and devices' specification documents
The key focus of WP4 will be on the finalisation of the proposed ANM control system which will support the application of real-time short-term post-fault OHL ratings. As part of WP4, interfaces between various control platforms will be established and user requirements defined.
Consideration will be given to retrofit requirements for the conductor temperature monitoring equipment, which will be suitable for installation on 33kV, 66kV and 132kV OHL distribution network. The specification will list a set of minimum technical requirements, suitable for tendering on the open market (i.e. vendor agnostic).
The output of WP4: will include a specification document for the ANM system (including proposed ANM control system architecture) and a specification for the retrofit conductor temperature monitoring equipment for OHL systems.
Work Package Five: Cost-benefits analysis and policy amendments
WP5 will aim to evaluate what impact an increase in post-fault capacity may have on the design life of OHL conductors, by exploring the high-level methodology for the existing ‘expected’ life span of OHL conductors, and determining any shortened life span should be expected due to elevated post-fault capacity.
The reliability of conductor temperature monitoring devices and network security options (if/when monitoring devices become faulty) will be evaluated with a failover arrangements within ANM considered shall conductor monitoring information become unavailable.
Relevant policies will be reviewed with recommendations for amendments drafted.
The output of WP5: will include a finalised cost-benefit analysis of the proposed solution, drafted policies with clear recommendations for amendments, a slide deck and other supporting presentation material to ensure effective project dissemination. Through voluntary contribution to the project Nortech (a project partner) will run at least four session with relevant NGED teams to demonstrate capability delivered as part of this project and potential benefits.