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Projects: Projects for Investigator
Reference Number	NIA_WPD_030
Title	LV Sensitive Earth Fault 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 Western Power Distribution
Award Type	Network Innovation Allowance
Funding Source	Ofgem
Start Date	01 March 2018
End Date	01 June 2019
Duration	ENA months
Total Grant Value	£166,835
Industrial Sectors	Power
Region	South West
Programme	Network Innovation Allowance
Investigators	Principal Investigator	Project Contact , Western Power Distribution (100.000%)
	Industrial Collaborator	Project Contact , Western Power Distribution (0.000%)
Web Site	https://smarter.energynetworks.org/projects/NIA_WPD_030
Objectives	Sensitive Earth Fault Protection for LV Feeders. This would be installed as a temporary retrofit before the commencement of any live working and removed after the work has completed. The additional protection would act to help prevent severe injury or death from inadvertent human contact with a live phase conductor during work on an LV feeder. The protection device that is required must therefore detect that contact has occurred and remove the supply before severe injury or death occurs. Survival from electric shock is dependent on the magnitude and duration of current flow. Therefore, there might be a useful trade-off between the required sensitivity of detection (and hence false negatives) and the speed of action of a device to remove supply. It is preferable for the device(s) to be easily fitted and removed in a relatively short time so as not to significantly increase the time typically required to carry out work on an LV feeder. It is preferable for the fitting and removal of the device(s) to not require any supply interruptions. This project aims to develop and prove the efficacy of methods which may be readily applied to the existing system to remove the supply in the event of a dangerous inadvertent contact with a live conductor when live work is being undertaken on the LV distribution system. A previous, WPD internally funded, project considered the potential application of existing, fast acting LV switching devices to cause an LV feeder to be shorted to earth, hence rupturing the LV fuse and removing the electrical supply from the feeder before the flow of electric current could cause a fatality. It established that a good quality earth connection can readily be made in LV substations, suitable for carrying current from a direct short to earth in the substation and causing the local protection to operate within sufficient time. It also established that the risk of fitting additional protection equipment is lower than the existing risk of live working. That project provides comfort that providing a method to detect accidental contact could be practically achieved, then it should be possible to implement appropriate fast-acting protection. This project seeks to determine a method which can detect the inadvertent contact and take fast action to remove the supplies and make the situation safe. The project has been established as a staged programme of work targeted at achieving the project aims in the shortest and most cost-effective manner. A number of possible approaches have been identified and those which have been judged to have the greatest chance of success will be investigated first. If these do not meet the requirements set out by Western Power Distribution then the project will investigate the other options in order of the lowest to highest estimated cost, complexity and practicality of rollout. Conversely, some elements of the project which are currently within scope will probably be de-scoped as learning from the project improves understanding. The project naturally divides into three workstreams: A workstream to test alternative methods to detect contact between a human and a live phase conductor, select the preferred option then produce and test a prototype detection device A workstream to define and test a retrofit device which can act on receipt of a signal to cause mains supply to be quickly removed from an LV feeder. A workstream to integrate the prototype supply interruption and detection devices and then test them in the field.
Abstract	NULL
Publications	(none)
Final Report	(none)
Added to Database	02/12/22