Power electrical engineering. Includes industrial electrical engineering (i.e. motors, switchboards), transmission and distribution (poles, wires, transformers, grids) and generation.
Questions tagged [power-engineering]
470 questions
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Can a bird, previously at earth potential, get electrocuted by landing on a powerline at high-enough voltage due to the initial "equalization charge"?
At the voltage levels of typical overhead transmission lines in the US, a bird can land on one and be just fine (as long as it doesn't do something like spread its wings and touch a tree or something else at lower electric potential).
However, what…
etherice
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What is this object found on transmission lines?
What are the components, circled in red in the figure, on this transmission line ?
Electrical Engineer
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52
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Why three-phase power? Why not a higher number of phases?
Is there a reason, beyond historical reasons, that three phases has become the dominant number of phases?
I am aware of the advantages against one phase and two phase, namely the reduced amount of conductor needed, and that motors can provide torque…
Hugoagogo
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40
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Why do utility companies supply at a frequency of either 50/60 Hz?
It just struck me that Utility Companies world-wide supply domestic users at either 50/60Hz. It could have been selected to be 10 Hz, or 100 Hz ... whatever
Was 50/60 chosen at random? Is there some rationale involved (efficiency, easier to…
Everyone
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38
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How do transposition towers in transmission lines work?
There're such things as transposition towers in power distribution powerlines. The idea is that for example you have three conductors running in parallel at the same height and the leftmost of them is phase A and after transposition the middle one…
sharptooth
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Why don't we use neutral wire for to ground devices and earth wire for closing the circuit?
I know that the neutral point of a distribution transformer is connected to the grounding (earthing) wire, so I think they are the same.
Can I use the neutral wire for protecting metal-cased electric devices by connecting it to the case (cover)?
Can…
Michael George
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If we could start our electrical grid from scratch with today's technology, which would be the most efficient choice? AC or DC?
Lately, I’ve been reading about the many advantages of HVDC transmission systems for long distance transmission, undersea links, and others. The historical reason of why AC was picked over DC was mostly due to the invention of the transformer, which…
Jota
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Why does power dip during a lightning storm?
If lightning were to strike power lines, wouldn't you expect it to increase the power, and hence your room lights get brighter?
Why do they go dim for 1 second at a time?
PJazz
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33
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How to ramp up a factory consuming a lot of energy?
Can you please explain how to manage the process of ramping up a factory with a big electric consumption?
I am wondering how it is possible to balance the grid during the start up phase of a big power consumer. When I turn on my kettle at home the…
Merlin Nestler
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What is the speed of "electricity"?
In a distribution grid, what is the speed of
energy
signal
Is it strictly the same?
And how is synchronisation achieved? Is an electric grid essentially an orchestra where everyone is the chief and gives the beat to everyone?
curiousguy
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Why 3 phase and not 1 phase power transmission?
Why does power transmission use three lines with three different phases? Why not three lines all in the same phase? Does it have to do with the alternators used for generating the power, or is there less loss when the phases of the three lines are…
Geremia
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Why are consumers located near high-voltage lines typically not connected to those lines but instead are connected through a lower high-voltage line?
A typical grid uses 110..500 kilovolts lines to deliver electricity to substations which lower that to 6..20 kilovolts and then lines with that lower voltage get to consumers where yet other substations are located which finally lower those 6-20…
sharptooth
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What happens to excess energy fed into the power grid?
The closest question to this is Linear useage of excess power generation.
I'm no engineer so I may not be able to phrase this correctly and would appreciate an answer which assumes minimal background knowledge (I have only a basic understanding of…
cluelesscoder
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What is this device attached to a high-voltage power line?
I noticed this white, cylindrical device on a power pole near Seattle that facilitates a 90-degree turn of the transmission line. It looks like the lightning conductor comes down the pole into a sort of service loop before disappearing into the…
Peter Schilling
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Why do condors get electrocuted by power lines?
Plenty has been said about why birds are safe to land on power lines. But condors, apparently, are not. The linked article explains that condors are electrocuted often enough and endangered enough that they are doing special "power pole aversion…
Nate Glenn
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