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UK Power Networks trial world’s fastest circuit breakers

Cable maintenance company UK Power Networks is trialling what it calls “the world’s fastest circuit breakers” in London.

The Power Electronic Fault Limiting Circuit Breaker devices were installed in an 11kV substation in Tower Hamlets, east London, in early January.

The fault limiting circuit breakers (FLCBs) were designed by ABB to interrupt faults as they occur. They are the first to use a fast commutating switch. They are a quarter of the size and half the price of the previous breakers and cut off power in 0.004 seconds.

Better response times should mean larger contingency capacity, allowing more generators to connect to a network. The company estimates the breakers could enable 460 MW of generation to connect to the network, saving £400m.

Trials of the breakers began in early January and will continue to August 2021. During this time, the company will gather performance data on different configurations.

Reports from these trials will be published on the UK Power Networks website.

UK Power Networks is also developing a safety case for the device “in order to develop the engineering knowledge necessary to safely and effectively demonstrate FLCBs on British networks”.



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