New ‘time reversal’ technology could locate power network faults in tens of seconds, reducing power outages and decreasing bushfire risk.
Developed by an international research team including Monash University and the Swiss Federal Institute of Technology Lausanne, the reversal technology comprises three steps:
- measuring the fault signals;
- defining the fault locations and injecting the time-reversed signals into a computer model;
- and evaluating the fault current at a guessed location, to identify the fault’s most likely location.
“Imagine a swimming pool with sensors around its perimeter,” said Dr Reza Razzaghi from Monash University’s Department of Electrical and Computer Systems Engineering.
“If a stone was dropped into the water, the ripples would hit the sensors and these sensors would record the waves generated by this stone drop. The time reversal technology can find the location of the dropped stone (in a computer model of the pool) by reversing the direction of the waves measured by the sensors.”
The technology was recently tested on a pilot network in Switzerland. Covering a wide range of common faults occurring in power systems, it was able to pinpoint fault locations with an accuracy of less than 10 metres.
In contrast to current methods, it requires just one measurement point installed at a substation and is able to locate faults within a few seconds to minutes.
With faults in power networks being one of the primary sources of major bushfires in Australia, including five of the 11 major bushfires during Victoria’s Black Saturday tragedy, the technology also has the power to save lives.
Victoria currently uses Rapid Earth Fault Current Limiters (REFCLs) across its high-risk rural power networks. These limit the energy supply when a fault occurs to mitigate any bushfire risks.
However, REFCLs cannot precisely determine where a fault is located, which means restoration crews can spend hours patrolling hundreds of kilometres of power lines in order to find the problem before they can fix it.
Thousands of people can be without power for several hours in extreme heatwave conditions as a result of this time lag.
Monash University Research Associate Dr Tony Marxsen said the time reversal innovation aims to ease the community impact of the current technology that helps to prevent fires.
“This technology offers the hope that faults can be pinpointed quickly, reliably and safely to, above all, reduce the impact on customers in very high stress conditions,” he said.
“[It] has the potential to save lives and ensure Australia is best prepared to prevent and tackle any catastrophic incidents that might arise as our country continues to get warmer and drier.”
A patent for the technology has been filed at Monash University and further research is being undertaken to adapt the technology to power networks in Australia.