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Projects: Projects for Investigator
Reference Number	NIA_UKPN0005
Title	Better Spur Protection
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 Eastern Power Networks plc
Award Type	Network Innovation Allowance
Funding Source	Ofgem
Start Date	01 April 2014
End Date	01 October 2017
Duration	42 months
Total Grant Value	£492,000
Industrial Sectors	Power
Region	London
Programme	Network Innovation Allowance
Investigators	Principal Investigator	Project Contact , Eastern Power Networks plc (99.999%)
	Other Investigator	Project Contact , South Eastern Power Networks plc (0.001%)
Web Site	http://www.smarternetworks.org/project/NIA_UKPN0005
Objectives	Prove device works as expected Prove device is compatible with the UK Power Networks SCADA system Prove device can be safely installed by HV Live Line teams Prove Wi-Fi security Prove device works in the same manner as an ASL The successful demonstration that the Fuse Saver can operate in a superior fashion to ASLs, and provide greater information regarding normal and fault conditions on the spur.
Abstract	The Better Spur Protection project was previously an IFI funded project that is now transitioning into a NIA project. Historically many rural customers are supplied via overhead line spurs from the overhead main line. This is a cost effective connection solution but increases the outage risk to rest of the overhead main line. In order to mitigate this risk many auto-sectionalising links (ASLs) have been installed on spurs in conjunctions with an auto-recloser on the main line. The ASLs allow the auto-recloser to protect against transient faults, but should there be a permanent fault on the spur then the ASL will drop out in the second deadtime of the auto-recloser. Every time an ASL drops out then the actuator needs to be replaced and re-inserted after the fault has been identified and repaired. This requires a linesman to go to the ASL location which could be some distance from the fault, in order to restore power to those customers downstream. For safety reasons the actuator cannot just be re-inserted in case the fault still exists. ASLs are not rated to fault-make. Therefore an aerial break switch disconnector (ABSD) or a vacuum circuit breaker will need to be opened upstream. The impact of this is additional switching and if the switch is not adjacent to the ASL then more customers may have to experience a temporary outage in order to restore the spur. A solution to this would be to have a reclosable spur switch that can be remotely controlled. The Fuse Saver is an in-line per phase vacuum breaker which can make or break under fault conditions. It does this within a half-cycle to protect the phase fuse. Should the fault be permanent in nature then the expulsion fuse will drop out. Fuse Savers have the ability of opening and closing remotely, monitoring the current on the spur, recording the magnitude of the fault within the fault event history, a range of definable protection settings, device battery life and vacuum interrupter life. Currently the Fuse Savers have been used in a number of different countries but not yet in the UK. The proposal of this device is that not only does it provide greater protection for customers per phase on the spur but it also reduces the risk of the spur to the main overhead line. Initial indication show that the Fuse Savers have lower operational costs and potentially the overall installation cost of the device is cheaper than the current solution which is ASLs that need to be installed with ABSDs. The monitoring functionality will be a crucial development in moving towards operating a smarter and more automated network. UK Power Networks’ pole-mounted transformers currently do not have a monitoring capability but by installing these devices on spurs it will be possible to have a better understanding of the load and generation demands on rural networks. Demonstration Identification of Trial Sites The business has identified "At Risk" overhead lines and spurs as part of the business as usual quality of supply process. This process has provided the best test cases for the trial. From the review of auto-sectionalising links, the key sites were identified for Fuse Saver deployment. Spur Risk Identification Process A script has been developed to trace down each feeder recording every overhead line spur off the mainline. From each of these overhead lines spur points the script then traces the rest of the spur: identifying if there are ASLs, counting the number of customerseither side of the ASL and measuring the length of the overhead line and underground cable either side of the ASL. If there are no ASLs on the spurs the script returns the number of customers and the length of overhead line and underground cable. The script finally produces a list of spur with the above characteristics for every feeder. Using historical data to find the fault rate, average CI and CML for overhead lines and underground cables in the locality of feeder, it is possible to discover the impact spurs have on the main feeder. Then by applying a ratio of spur length to feeder length it is possible to rank the spurs by order of impact. By removing the spurs that already have ASLs fitted, it is possible to achieve a shortlist of spurs for intervention. This approach is then compared to the results of the Worst Performing Circuit in order to validate and calibrate the results. The Worst Performing Circuit process is an annual review conducted by Asset Management which ranks feeders by the number of faults and the financial impact of CIs and CMLs. The thresholds vary for each DNO depending on the target number of faults and outage duration. Test RTU and Fuse Saver Compatibility It will be necessary to test that the Fuse Saver in the Operation Telecommunications Labs to ensure that the RTU can communicate with the three Fuse Saver vacuum interrupters and collect all of the necessary information. It will be important that this information can then be communicated back to the control system so that the devices can demonstrate the open/close functionality and that it is possible to record the current measurements. It is intended that two Fuse Saver devices will be withheld from the initial installation programme to facilitate the training of staff in the installation, commissioning and operation of the devices. Installation of RTU and Fuse Save rafter passing the compatibility test the devices will need to be installed and commissioned in multiple sites. Each site will require the necessary design and safety planning. Coordination within existing feeder protection schemes Once the devices have been installed it will be necessary for a protection engineer to commission the protection settings to coincide with the existing circuits protection settings to ensure effective and safe device operation. Assessment of project Once the devices have been installed it will be necessary to test the following: Communication capability with the control system Operation under fault condition (simulate if necessary) - Phase to Phase transient - Phase to Earth transient - Phase to Phase permanent - Phase to Earth permanent Storage of current measurements By installing these devices over a broad area with high fault rates, this will provide real fault operations as evidence of how the Fuse Savers are working.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	07/06/18