Wireless sensor networks for detecting imminent faults at substations
03 April 2013
A research project promises a more efficient technique for detecting potentially dangerous and destructive faults atn electricity substations.
Ian Glover, a recently appointed Professor of Radio Science and Wireless Systems Engineering at the University of Huddersfield, conducts research into the use of easily-installed wireless sensor networks in power distribution substations. This technology is designed to locate and diagnose imminent system faults, so that repairs can be made.
Professor Glover explains that when the insulation of cables and other power equipment becomes old or damaged, it radiates microwave energy, known as partial discharge.
“This can be picked up by radio receivers and by monitoring the intensity of this microwave energy, you can predict when an item of plant is going to fail.”
Traditionally, partial discharge has usually been detected by a technician walking the substation with a radio receiver and a pair of headphones.
“He listens to an audio signal that simply gives some basic information about whether partial discharge is present or not and with a bit of luck, the closer he is to the partial discharge the more intense it sounds,” said Professor Glover.
“That might typically be only done once a year, but that is not enough. A piece of equipment can degrade very quickly.”
In the worst cases, equipment can explode, leading to power cuts and massive repair costs. There is also a safety risk, though modern sub-stations in the UK are not generally manned.
Professor Glover is the lead investigator on an EPSRC funded £670,000 project to develop the principle of wireless sensor networks, which can be monitored centrally.
“You get a quicker diagnosis and it means that you can move from planned maintenance to condition-based maintenance,” explained Professor Glover. “You don’t have to maintain everything quite so often if its health is being measured all the time. You can wait until something is about to go wrong.”
This would produce efficiency savings, cut down on the cost of equipment replacement and avoid the large fines levied on utility companies in the wake of power cuts.
Free space radiometers
The novel feature of Professor Glover’s research is that he would use free space radiometers to sense microwave radiation intensity. These instruments are not attached to the power cables and can be installed without switching high voltage equipment off, so there is no interruption to power supplies.
“They can be reconfigured and installed very quickly and very conveniently and do not require demanding time synchronisation.”
Professor Glover’s colleagues on the four-and-a half-year project will include physicist and engineer Dr Maria de Fatima Queiroz Vieira, who retires soon from her post at the Federal University of Campina Grande in her native Brazil to take up an honorary appointment at the University of Huddersfield.
PhD students and post-doctoral researchers will also be recruited for the project – which will take place in a new, specially-equipped £100,000 lab at the University of Huddersfield – and Professor Glover will also work with colleagues from Strathclyde University, where until recently he was Reader in Radio Science and Wireless Communications.