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Physics/Why do some transformers burn out during current surges ?


Hello Steve,

In a scientific book that I am reading, the author describes : When aurora activity is unusually high, large transformers in Canada have been known to burn out and even explode. At the same time, increase of current flow in power lines has been great enough to trip circuit breakers as far south as Texas. As explained before, the concentration of the electrons in the atmosphere is greatly increased during auroral phenomena. Some areas, of course, receive much higher concentrations of electrons than others at the same latitude......"

My question is, why do transformers explode or burn out during powerful auroral activity ?
Could you explain the mechanism (steps) of this process ?
Keep in mind that the cables are isolated in a transformer, so static charges seem a bad candidate for the reason !

Hmm, while the electromagnetic field is changing with time, this may create a secondary electron flow (current) in the cables of the transformers, by this way there seems an increase in the current which may melt the isolation of the cable and create a short circuit effect which means damage. Could this be the
reason ?

Yours Sincerely

It's not the transformer, it's the power grids themselves.  There have been whole international conferences on this subject, how to protect the power grid during disturbances of the Earth's magnetic field due to impacts with solar coronal mass ejections.  Faraday's law dictates that in a massive power grid (very large area) there will be a massive surge in voltage during fluctuations in the magnetic field.  The points where these wires connect are in the transformers that convert the voltages.  Hence they blow up when overloaded.  The aurora is a coincidental effect, but are related to the shifting magnetic field.  It's not surprising that they blew up specifically in Canada, as that's where the magnetic north pole is and by far the closest major power grid to such directly vertical magnetic field.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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