Broken Mechanism of Straight Cu Conductors due to Lightning High Impulse Current

When a high impulse current flows through a conductor, the conductor may be melted due to the current value and duration. A straight moderate copper conductor such as 1mmφ is melted by a relatively small DC current in hundreds of amperes due to the steady thermal transfer from the surface of the conductor to the ambient. Moreover, a thin conductor such as 0.1mmφ is melted by a relatively large impulse current due to the specific melting Joule integral: (j²t)m in an adiabatic condition and so on. However, this time it has been recognized that a moderate conductor of 1mmφ is not completely melted, but broken by an impulse current with a roughly equal or smaller than expected melting peak value. Therefore, an electro-magnetic mechanical force, a decrease of effective cross-section due to the skin effect, etc. are discussed as breaking mechanisms adding to the ordinary Joule heating energy.     «

When a high impulse current flows through a conductor, the conductor may be melted due to the current value and duration. A straight moderate copper conductor such as 1mmφ is melted by a relatively small DC current in hundreds of amperes due to the steady thermal transfer from the surface of the conductor to the ambient. Moreover, a thin conductor such as 0.1mmφ is melted by a relatively large impulse current due to the specific melting Joule integral: (j²t)m in an adiabatic condition an...     »