Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [power-grid]

Refers to grids or networks that deliver electrical power on a large scale, that is, networks for bulk power transmission. For smaller scale networks, refer to distribution-network or microgrids.

Power grids or power networks typically refer to bulk power generation and transmission resources. The term power grids is more suitable for high-voltage transmission networks and should not be used to describe distribution networks or microgrids.

Power grids typically transmit bulk electrical power from large generation facilities and deliver it to load centers.

The study of power grids may involve their stability properties (rotor-angle stability, small-signal stability), steady-state power transfer capability (sometimes referred to as voltage stability), network expansion, resource adequacy, reliability, operation & control, and the underlying electricity market.

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Serbia, Kosovo power grid row delays European clocks. Why?

According to this article (and a lot more published today on the same topic), Kosovo electricity net production balance has decreased during the last weeks. This has led to a small deviation of the European network’s frequency (from 50Hz to…
Evariste
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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 do power grids tend to operate at low frequencies like 60 Hz and 50 Hz?

I understand that a two-pole AC generator has to rotate at 3600 rpm (60 Hz USA) in order to maintain a 60 Hz frequency and higher frequencies would require these generators to spin even faster which could be problematic. I also understand that…
ZekeC
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5 V home network

I'm planning on adding multiple IoT devices in my house, and I'm looking for an elegant solution to power them all. They'll all need 5 V, a small number of them (cameras) would draw up to 2 amperes, while most of them would draw less than…
Velimir Tchatchevsky
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Staying in Phase On The Grid

I have been an EE for over forty years and never did find out the right answer to this one.... How do power-stations and transformer switching stations ensure that the power they are feeding into the grid is in-phase with the existing power on the…
Trevor_G
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How do large electrical grids stay in phase?

I am a math student with some background in physics so apologies if the question is naive - but I'm trying to understand how large electrical grids like the Eastern Interconnection maintain locally a consistent phase, when it seems like the grid…
Dominic Wynter
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How can energy "physically" be fed back into the grid?

I have found some similar questions (below), but I am still having issues understanding what is "physically" happening when energy is "fed back into the grid" and the equipment necessary for this. What happens to excess energy fed into the power…
W. Churchill
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What happens to excess electricity generated going in to a grid?

How is excess electricity generated dissipated? I know that the grid is balanced, etc. But given that there will be momentary over-generation at some point over the whole grid where does any excess electricity go? For example, in the event of a…
BMA1200
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Why do underground cables "require a higher degree of reactive power compensation" than overhead lines?

I was reading a brag sheet for a certain company's giant transformers, and I came across this sentence: Furthermore, in some regions, the existing over head lines are being replaced by underground cables, which require a higher degree of reactive…
flaviut
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Are these transformers or giant capacitors?

I sometimes see these devices along power lines when I'm driving and was wondering what they were. They look just like the regular transformers that I see on top of electrical poles, but it seemed strange to me that they each had two connections to…
amazonprime
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What is the reason for these utility poles with a 6-sided hole in the middle for conductors

What would be the technical (Electrical, structural, safety) reasons for a utility pole like those shown below? This picture was taken in Arkansas and is what I assume to be 3-phase power. Note how in one picture the poles transition back to normal…
Austin Downey
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What are these circular basket-like structures on a high voltage transformer's insulators?

Wikimedia commons contains this public-domain image of a high-voltage transformer of the Tarza power plant in Iraq, taken by Marvin Daniels in the U.S. Army: There is much I do not immediately understand about the design of the transformer from…
Landak
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Why/when is AC-DC-AC conversion superior to direct AC-AC conversion?

I am currently studying wind power and the power electronics used for it. In wind power a generator is driven by wind, thus the resulting power is of widely varying frequency and amplitude. The power grid, in turn, has strict requirements for the…
ckrk
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Purpose of cylindrical attachments on Power Transmission towers

Attached below is an image of a Power transmission pole. What I am interested in is the cylindrical shaped objects attached to the transmission tower. Some other observations and relevant information: These objects are not present in every tower…
ijuneja
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