Critical Disruptive voltage is the voltage stage where the corona effect occurs between a transmission line’s conductors. The distance between the two conductors is larger than their diameters; the air surrounding them is subjected to electro-static stresses.
If the potential difference applied reaches a value, the air between the conductors gets ionized, producing ions. And this ionization causes an electrical discharge; that is the corona effect. And that voltage stage better two conductors is called Critical Disruptive Voltage.
Critical Disruptive Voltage Circuit Understanding
If we consider two-conductor A and Conductor B of the same radius r, d is the distance between them, and their phase to neutral voltage is V; so, Vc will be defined as critical disruptive voltage. Here is the diagram of critical disruptive voltage below:
Critical Disruptive Voltage Formula
Critical disruptive voltage formula, Vc= m0g0δrln(d/r)kV/phase
Critical Disruptive Voltage Formula Explain:
Vc = m0g0δrln(d/r)kV/phase
mo = 1 for smooth and polished conductors,
= 0.92 to 0.98 for rough conductors, and
= 0.87 for stranded conductors.
So, Critical Disruptive voltage is a voltage between two conductors in the transmission line when the corona effect occurs. And the formula of Critical Disruptive voltage Vc = m0g0δrln(d/r)kV/phase.