• batmaniam@lemmy.world
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    7 months ago

    OK, I’m going to save you time because I do some controls and totally get how “easy” demand management should be given how simple most devices are.

    But WHAT?! Thats all built into the grid over there??? That’s AWESOME. Let me see if I have this right: there’s essentially a small transient frequency modulation in the 60hz(?) in the grid that allows devices to receive a “off” signal?

    I could be wrong but I’m 90% sure we’ve got nothing like that in the states. MAYBE there’s something like that for communicating with the meter itself but certainly not past the meter.

    • ChaoticNeutralCzech@feddit.de
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      7 months ago

      I think you might have it in the US but not for residential customers.

      No, frequency-modulating the 50/60 Hz is not technically feasible, that would mean speeding up/slowing down lots of synchronous motors quickly. Instead, a higher-frequency low-voltage generator is connected in series or in parallel (via a capacitor) to the secondary of a grid transformer, overlaying some 3V sine wave at 216⅔ Hz (or other frequency thereabouts) on top of the 230V 50Hz mains. This does not propagate beyond 50 km or so (and higher frequencies (red on map) even worse) so multiple transmitters are required for coverage. The country’s grid is divided into districts and each gets their own RCS signal, and signal traps (low pass or band stop fiters) are used to divide them.