My Idea for Power Grid Solar Flare Protection

361

01:57:50

If a large solar flare strikes Earth, it will cause catastrophic damage by generating thousands or millions of volts across very long power lines. By using a transformer, one can short common-mode voltage (generated by the flare) to ground without also shorting out the differential voltage (which is how the power is transmitted). On the left is a two-phase 60Hz power source of 10kV plus a 10Hz 100V common mode power source representing a solar flare. As you can see the transformer in the middle presents a very low impedance to the common mode signal but doesn’t affect the differential signal where the power is transmitted. By employing such a transformer, one can provide passive protection against solar flares without impacting the grid’s performance or drawing unnecessary power. Of course, because the transformer has a non-infinite inductance it will draw some current, but that’s what power factor correction capacitors are for. If the appropriate value of capacitor is placed between the two lines it will cancel out the inductive current of the transformer leading to virtually zero current except to account for losses in the transformer, but that should be very small.

published 4 years ago

guillianj

4 years ago

This doesn’t look doable for 3 phase. And the 2 phase with a 180 degree offset is highly impractical. Most electromotors will only work on 3 and higher.

jason9

4 years ago

Perhaps with a 3 winding transformer it can be done on 3 phase, but I’m not sure. Also why is 180° impractical? I know we either use 3-phase or 1-phase plus neutral, but I don’t see why a 2-phase setup would be impractical. And a neutral wire can still be used and it wouldn’t even have to conduct much current since most current going in one power wire will also be going out the other power wire.

jason9

4 years ago

Ok, I did some research and it looks like standard 3-phase transformers are already in the right configuration to short out common-mode voltages to a neutral wire if the transformer is core-type and not shell-type and the connection is a wye (Y) connection and not a delta (Δ) connection. Of course this doesn’t protect everything as obviously not all existing connections meet these requirements, but it’s likely that many already do so that’s good to know.

guillianj

4 years ago

Yeah there you go. And 2 phase is impractical because 3 phase is like the minimum to smoothly run electromotors. There are some tricks you can do by creating a 90 degree offset on one phase with a capacitor to effectively run an electromotor on 1 phase by creating the 2nd one yourself (but notice how it’s a 90 degree offset, not 180, you can’t really do much with 180), which is what fridges do, but these are less efficient and less powerful. Historically there were some 2 phase networks with a 90 degree offset, but these were abandoned: https://en.m.wikipedia.org/wiki/Two-phase_electric_power

add comment in editor

EveryCircuit is an easy to use, highly interactive circuit simulator and schematic capture tool. Real-time circuit simulation, interactivity, and dynamic visualization make it a must have application for professionals and academia. EveryCircuit user community has collaboratively created the largest searchable library of circuit designs. EveryCircuit app runs online in popular browsers and on mobile phones and tablets, enabling you to capture design ideas and learn electronics on the go.