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“It’s a bit like blowing up a balloon” says Jean-Bernard Dastous, a research scientist
from Canadian power supplier Hydro-Québec, which collaborated with ABB on the

project. “If it’s very rigid, it will be difficult to expand the balloon. But if it’s made of
a very flexible material, it’s easier for you to inflate it.”

To design what ABB calls an “arc resistant” tank, the team first had to create a

mechanical model that could predict the pressure at which a given tank would
deform and subsequently rupture, based on its size and material properties. Hydro-
Québec, in particular, wanted ABB to build a tank that could withstand 20 MJ of

energy without rupturing—a level that would cause a “catastrophic failure” in most
transformers and one that Dastous says “would cover 95 percent of faults occurring

on the network.”

ABB spent months building a full size tank. For safety reasons the tank was filled

with water instead of oil and contained a replica of the active part of a transformer.
In the first test, the team injected pressurized air measuring 200 atmospheres . The
tank bulged at its sides, but did not explode. In the second test they hoped that the

tank would rupture at a given pressure at the top because less oil will spill into the
environment. Their test methodologies worked. The specifications, to be
implemented in the coming months will hopefully lead to fewer transformers

exploding.

Brodeur says: “Because we are able to prevent most of the tank rupture cases, it’s
safer for the people who work around the transformer and it’s also very good for the
environment because we can prevent major oil spills and toxic fires.”

Source: https://spectrum.ieee.org