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by wintermutesGhst 3028 days ago
My confusion always comes when I try to think of it as a propagating wave.

If instead of a tandem bicycle, it is a very long rope that someone is moving up and down, then when I try to join some distance away there will seem to be a wave passing me. Even if I join in at the correct phase, I will also be generating a wave traveling back to the first 'generator' and interfering with the existing wave along the way. With the right distance and relative strength then we will produce a standing wave between us. Is there an apparent 'direction' to the wave of electric potential in a large grid?

Then there is the issue of triangular arrangements the sibling comment raised, when the radial distances and relative phases don't align.

Maybe my issue is always trying to think through physical analogues I can 'see'.
2 comments
pjc50 3028 days ago
Note that the wavelength of 50Hz at 'c' is 6000km. There's not a lot of space to get very much out of phase and it will attenuate along the way.

The nearest I can think to "direction" is "reactive power", or the phase angle between voltage and current at any particular point.

There very definitely are loops and multiple paths to a particular point, it's not called a "grid" for nothing. This little map of the UK grid is interesting: https://www.nationalgrid.com/uk/about-grid/our-networks-and-...

Edit: Aha, further reading - systems for altering the phase angle: https://en.wikipedia.org/wiki/Quadrature_booster

And https://www.researchgate.net/publication/27341916_Influence_...

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theoh 3028 days ago
Along with quadrature boosters, there are (used to be?) these things, synchronous condensers: https://en.wikipedia.org/wiki/Synchronous_condenser
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_trampeltier 3028 days ago
But with 1500km it would be 90° out of phase and that would be already a pretty high voltage.

I'm also wondering since a couple of years about the same question.

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emilecantin 3028 days ago
Your issue is seeing 2d (perpendicular) waves where there are actually 1d (parallel) waves. Also, you're not really creating a new wave, you're just giving a "push" to the existing one.
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