it depands on switching overvoltage or lightening overvoltage.
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EHV - EXTRA HIGH VOLTAGE - STARTING 500 KILOVOLTS IN UP (500,000 VOLTS)
220 KV lines used in Kerala have a capacity of 880 Amps
Carry electrical power over extremely long distanceswith minimal I2*R losses. The higher the line voltage the lower the current the line has to carry to transmit the power from source to load.
It depends on the nature of the transmission line mostly under a fault it is the inductance that will be limiting the fault current so your power factor would be quite low. The exact number would change from line to line. During a fault (say three phase fault for simplicity), the power factor will drop to the line angle (assume no, or very little fault resistance). On EHV systems, this is in the 80 - 88 degree range (typically). On VHV, it is often in the 70-80 degree range. A line angle of 90 degrees is a pf of 0, so to convert between this line angle and power factor: pf = cos (line angle). As voltage gets lower, the assumption of no fault resistance becomes less valid, and the line angle becomes less (increased power factor). The lowest VHV line angle I've seen is in the 60-70 degree range. I've seen 40-60 on HV, and as low as 30 degrees (.86 pf) on underground cabling.
EHV lines are type of electrical lines commonly used for experimentation in physics. They stand for 'Extra High Voltage' lines.
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Answer 1. The only shunt reactors I know are used on transmission lines to alter power factor. This is nothing to do with the nuclear reactor in a power plant.Answer 2. I agree. Shunt reactors are use on transmission line and EHV to boost voltage, to generate VARs and for power factor correction.
EHV - EXTRA HIGH VOLTAGE - STARTING 500 KILOVOLTS IN UP (500,000 VOLTS)
220 KV lines used in Kerala have a capacity of 880 Amps
current does not flow through insulation under "normal circumstances". The air itself is often used as an insulator in HV and EHV electricity. When lightning strikes, it ionizes (lines up the molecules) in the air, causing a breakdown in the insulation strength of the air, which sometimes allows current to flow from one conductor to another in overhead power lines. This is called a "fault" and results in massive power flow until protective equipment interrupt the flow, and give enough time for the air do de-ionize before resuming normal operation.
That's what they say so it is!
EHV = Extra High Voltage. To quote from the Wikipedia article (see link) "...this refers to equipment designed for more than 345,000 volts between conductors." Put simply - EHV transmission is the 'national grid' power system.
The distance between high voltage lines is governed by either a switching impulse voltage or lightning impulse voltage. The distance between lines, or lines and tower must have a high enough dielectric strength to avoid flashover at these voltage. Air can withstand a voltage of 3kv/mm.
MAT-VE-AY-EHV
The three types are Line to ground faults line to line fault double line to ground fault three phase line to ground fault