4 ms·
The choice of 50/60Hz is an engineering trade off. Engines, Turbines and alternators are happiest spinning in 100s to 1000s of revolutions per minute range. At
by PoachedSausage 9y ago
The choice of 50/60Hz is an engineering trade off. Engines, Turbines and alternators are happiest spinning in 100s to 1000s of revolutions per minute range. At that RPM range, alternators with 2, 4, 6 etc magnetic poles translate to AC line frequencies in the 10's of Hz range. AC power on aircraft is usually at 400Hz because it makes equipment lighter.
It is similar with the choice of 3 phases for electrical power distribution, you can add more phases but it just adds to the cost with little benefit.
- leggomylibro 9y agoHuh, cool; you learn something new every day! Jeez, when it comes to electricity, it is just like peeling an onion with layers of ignorance...
- m4x 9y agoAnother relevant trade off is transformer size vs. efficiency. AC is used because it's very simple to step up to very high voltage for efficient long distance transmission and then back down to safer low voltages for use, while doing the same with DC requires significantly more complex electronics. However, at very low frequencies you need to use very large transformers which cost a lot and look ugly, and at higher frequencies you lose efficiency due to skin effect [1]. 50 Hz is a good compromise - transformers are of a practical size and skin depth is about 9 mm, which is larger than most conductors and therefore doesn't add much loss. If you increase the frequency to just 10 kHz (which is still considered very low) the skin depth decreases to only 0.6 mm, and you would have significant loss on even moderate sized conductors. [1] https://en.m.wikipedia.org/wiki/Skin_effect https://en.m.wikipedia.org/wiki/Skin_effect
- deleted 9y ago[deleted]