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Projects: Projects for Investigator
Reference Number NIA_NGET0109
Title Bushing and Instrument Transformer Test Tap Connection Condition Assessment Tool
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 November 2013
End Date 01 May 2017
Duration 42 months
Total Grant Value £240,000
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_NGET0109
Objectives The objective of the project is to develop a novel integrated solution for condition monitoring on bushings and Instrument Transformers. Then, we need to test the solution to see how effective it is. Lastly, we will develop an implementation procedure to ensure the solution gets fully implemented into the business. An implemented Bushing & IT, and CT condition monitoring solution A business implementation procedure
Abstract Driver 1: National grid use Current Transformers (CTs) to measure the current on a particular point of a circuit. This measurement is then used to assess whether the current is within appropriate limits. Following a disruptive failure of a Reyrolle Hairpin type Current Transformer, approximately 200 Risk Management Hazard Zones (RMHZ) were established around affected assets due to concerns over moisture and Dissolved Gas Analysis (DGA) levels. This is relevant as an increased level of moisture and/or DGA within the oil contained within the CT can cause a breakdown in the electrical insulating properties of the oil. This in turn can cause the unit to fail. The RMHZ are to remain in place until either a satisfactory oil sample can be attained, or the unit is replaced. Driver 2: A bushing is used to protect the electrical components as they transmit electricity from the inside of the transformer to the outside, where it joins the rest of the transmission network. It does this in such a way that it electrically isolates the transformer casing at the same time. A typical example of a transformer with bushings is shown below: (The bushings are the 6 spiky bits on top) In the past, there have been several incidents of bushing failures that have caused catastrophic failure of transformers. Below is a series of photos that shows the effects of a transformer failure: Traditionally, bushings contained oil which could be sampled to give an indication of their condition. New bushing designs have engineered the need for oil out. Therefore, we need a new method of monitoring the condition of these new type bushing. The problem we are faced with is that the equipment we have identified to do all the different parts of the total solution are not compatible off the shelf. This condition monitoring solution will be able to address both drivers. Development The proposed method is to purchase a list of the following equipment from the suppliers identified to create 2 trailers that have the capability of real time condition monitoring: Elimpus - conversion of 2 trailers to take direct tap inputs and to provide measurement of leakage current and Partial Discharge Elysis - bushing tap monitor ISL- communications system to enable cross site monitoring for Elysis and GE GE - leakage current and PD off the shelf system for 6 transformer bushings, installed including specially designed tap connectors Optris - 2 x infra red camera with analytical monitoring software; this package will allow remote viewing of images and windowed alarm generation of selected/targeted items in the field of view. When purchased, National Grid engineers will make changes to the equipment to ensure the equipment talks to each other to give the solution, and then the solution can be implemented into the condition monitoring programme if successful.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 10/07/18