The power plant generates three different stages of AC power concurrently, and the 3 stages are balanced out 120 degrees from each other. Four wires are coming out of every power plant: the three stages plus a neutral, or ground common to all three. If you were to check out the three phases on a chart, they would resemble this about the ground:
There is absolutely nothing magical about three-phase power. It is merely three single phases integrated, as well as countered by 120 degrees.
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Why 3 stages? Why not one, two, or four?
In 1-phase and 2-phase power, there are 120 minutes per second when a sine wave is crossing no volts. In 3-phase power, at any provided minute among the 3 stages is nearing an optimal. High-power 3-phase electric motors, utilized in industrial applications, and points like 3-phase welding devices, as a result, have even power outcomes. Four phases would not significantly enhance points; however, would include the 4th wire, so the 3-phase is the all-natural settling point.
And also, what regarding this “ground,” as stated above?
The power business essentially uses the earth as among the cords inside the power system. The earth is a respectable conductor, as well as it is significant, so it makes a great return course for electrons. Vehicle suppliers do something similar; they use the metal body of the vehicle as among the cables in the vehicle’s electrical system and attach the adverse pole of the battery to the vehicle’s body.
“Ground” in the power grid means literally “the ground” that you are living on and you are strolling outside. It is the groundwater, dirt, rocks, etc., of the earth.
The three-phase power leaves the generator and goes into a transmission substation at the nuclear power plant. This substation utilizes huge transformers to transform the generator’s voltage, which is at countless volt degrees, up to incredibly high voltages for long-distance transmission on the transmission grid.
You can see at the back numerous three-wire towers leaving the substation. Normal voltages utilized for long-distance channeling remain in the series of 155,000-765,000 volts to decrease line losses. A common maximum transmission distance has to do with 300 miles or 483 km. High-voltage transmission lines are rather apparent when you see them. They are normally constructed from substantial steel towers similar to this:
All power towers like this have three wires for the three phases. Numerous towers, like the ones revealed above, have added cords leaving the tops of the towers. These are ground cords and exist primarily in an effort to draw in lightning.