Electric power grids, communications and navigation systems (including GPS), and satellites (including weather) could be damaged beyond repair for many years.
A monster blast of geomagnetic particles from the sun could destroy 300 or more of the 2,100 high-voltage transformers that are the backbone of the U.S. electric grid
There is always a small amount of natural electricity running through the ground. Under most circumstances, this electricity is harmless; however, a solar storm can exacerbate the currents underfoot, possible wreaking havoc on electrically linked systems around the world.
Can't the power grid's transformers be protected with spark-gaps ? used as over-voltage protections ?
The problem is the very low frequency AC induced saturates the transformers and causes them to fail after they go into saturation. Not high voltage just high current which is not sensed by the line monitoring as that is designed for the grid frequency.
Can't the power grid's transformers be protected with spark-gaps ? used as over-voltage protections ?
Yes, they can and they are. In fact, most grid components have several layers of protection devices: spark gaps, fuses, breakers, etc.
the problem is the dc current partly saturates the transformer, and the ac power lost in the core melts things down. the actual current doesn't have to increase much.
I'm supposed to understand that I can have a potential difference of 100.000 V between a power plant's earth net and the one of a city 1000km away from it ?
the problem is the dc current partly saturates the transformer, and the ac power lost in the core melts things down. the actual current doesn't have to increase much.
Aren't the transformers also monitored thermally? The larger ones have rather sophisticated thermal management systems, with oil, pumps, radiators, blowers, etc.
Yes, monitored, but...
The 250kVA unit I use is about 5 cubic metres in volume, and about half is cooling oil inside the tank. No protection aside from a set of HRC fuses on the 11kV primary side ( really big fuses though) and the assorted 200A fuses on the output 400VAC 3 phase side. the cabling on the primary side has earth fault relays on it, and this will trip out for arc faults inside the transformer and in the cabling as well.
Forgive me for asking a stupid question, but why wouldn't a blatantly obvious solution of adding (huge) capacitors in series with the transformers work, to block these DC currents?
There have been many scenarios played out on the subject of solar storms. About all they agree on is that there isn't too much we can do about them. As a worst case, the worst storm would mean the only way to protect the main transformers would be to take them off line prior to the storm hitting. Better a couple of days without power than having to replace some of the big transformers which have lead times of 18 months or more.
There have been many scenarios played out on the subject of solar storms. About all they agree on is that there isn't too much we can do about them. As a worst case, the worst storm would mean the only way to protect the main transformers would be to take them off line prior to the storm hitting. Better a couple of days without power than having to replace some of the big transformers which have lead times of 18 months or more.
And don't forget that the 18 month lead time is under normal conditions. What's the lead time going to be when power companies all over the continent (or further?) are all screaming for new transformers? 2 years? 5 years?
Ed
There have been many scenarios played out on the subject of solar storms. About all they agree on is that there isn't too much we can do about them. As a worst case, the worst storm would mean the only way to protect the main transformers would be to take them off line prior to the storm hitting. Better a couple of days without power than having to replace some of the big transformers which have lead times of 18 months or more.
And don't forget that the 18 month lead time is under normal conditions. What's the lead time going to be when power companies all over the continent (or further?) are all screaming for new transformers? 2 years? 5 years?
Ed
Plus the additional time needed if the supply chain is shut down for lack of power. One of the articles on this subject that I read a couple years ago said that the US does not even have an indigenous manufacturer of the largest transformers so they would have to be imported.
The emergent need for new and transformers and interim transformer repair could just as easily spur market entry and innovation, resulting in shorter lead times. IMHO, people are at their best in challenging circumstances. Things can get done that would not get done in normal times.
The emergent need for new and transformers and interim transformer repair could just as easily spur market entry and innovation, resulting in shorter lead times. IMHO, people are at their best in challenging circumstances. Things can get done that would not get done in normal times.
You will most likely simply be able to repair the transformers in a shorter time frame, provided your company still has the knowledge, material and equipment to do so, and that some bean counter has not outsourced it all to save a few cents per year. Repair will be a lot simpler if it has merely tripped out from overheating, as then the majority of the core will still be usable, and you might only have to only rewind small sections of coils that are failed.
I guess Dr. Diesel hasn't been on. This thread is right up his alley since IIRC he manages a coal fired power plant.