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Projects: Projects for Investigator
Reference Number NIA_NGET0156
Title DNO Investigation into Voltage Interaction and Dependency Expectation (DIVIDE)
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 April 2015
End Date 01 June 2018
Duration 38 months
Total Grant Value £376,000
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_NGET0156
Objectives Via further trials, improve modelling and understanding of the voltage dependant behaviour of load during periods of emergency voltage reduction Use this understanding to propose alternative control and design options for future connections Consider future challenges associated with new types of load/ generation connection and propose any alternative control strategies particular to these cases. Use the improved modelling to further inform voltage dependent modelling and forecasting in representing the future range of control actions available. To have WP1-3 completed in order to conduct trials across 2015/16 encompassing winter peak and summer minimum load conditions at high and low EG penetrations. To conclude upon alternative control approaches and confirm their technical viability in principle
Abstract This project seeks to gain an improved understanding and modelling capability of the existing voltage dependant behaviour of Active Power demand as may be instructed by the GB System Operator in part of Demand control activities to secure the supplies upon the transmission system at the time. From this improved capability this project shall seek to identify future capability and strategies which would maximise this capability going forward. National Grid ("NGET") discharges the role of System Operator within Great Britain, ensuring that system demand and generation are continuously in balance in order to maintain system availability and reliability. To this end it may be necessary at times of particularly adverse network stress to exercise a degree of demand control to maintain this balance. This is an area of control required to remain within the operators’ repertoire as per Grid Code Operational Code 6 (OC6). Traditional approach under Grid Code OC6 has been to under such emergency scenarios seek to reduce the voltage target at the Transmission/ Distribution interface as a method of achieving a reduction in demand. The benefit of this technique is that, unlike demand shedding, no physical load is disconnected, rather encouraged to consume less power, and accordingly there are no customer minutes lost, and no issues in disconnection and reconnection of load. This approach is founded upon the voltage dependant behaviour of motor loads, coupled with the normal operational principle of the distribution system which is to define the cascaded voltage profile of the radial distribution system to the point of load connection relative to, in effect the voltage targets assumed at the Transmission/ Distribution interface. The assumption has been that a voltage reduction of 5% delivers a 3% reduction in active power, but this assumption has been subject to limited practical trials since privatisation. Under "Project Juniper" conducted across October 2013, this effect was trialled in a series of trial activities with the DNO community with the following consequences/ impacts concluded: -A much lower average behaviour of 1. 5% reduction was achieved across the trials but there was much variance across DNOs. Little clarity and consistency on trials or on process for demand control across interface. Little understanding as to why effect was so small or so variable. Under GC050, NGET investigated with the DNO community next steps responding to the outcome of the trial. This lead to Grid code change to OC6 placing a time limit on the time for demand control via voltage reduction to be achieved and noting the 1. 5% expectation. However both SO and DNO community are concerned over practical ability to sustain this technique of demand control due to the low level of understanding of the issue and confidence of its resolution. This project intends to address project objectives through the following Work Plans of activity: -WP1. 1 Review of the current demand basis and behaviour based on available information. WP1. 2 Review of the current generation basis and behaviour based on available information. WP1. 3 Simulation of response to voltage reduction anticipated from the current network WP2. 1 Assessment of DNO actions involved in trials WP2. 2 discussion and agreement with DNO to revised trial approach WP3 Design, planning, and implementation of trials WP4 Conclusions, proposals for improved control design, forecast of the future network challengeNote : Project Documents may be available via the ENA Smarter Networks Portal using the Website link above
Publications (none)
Final Report (none)
Added to Database 09/08/18