Study on Mechanism of Lightning-Caused Breakage and Protection Measures of Bare Conductors

The 10kV distribution line is a main part of the power grid, and lots of bare conductor are applied to the overhead transmission lines. Meanwhile, the distribution lines can be easily struck by the lightning, which may lead to the disconnection of bare conductors, bringing threat to the safe and stable operation of the power grid. Therefore, it is urgent to carry out systematic research on the mechanism of lightning-caused breakage of bare conductors, and the protection measures of 10kV overhead lines. Firstly, the distribution law of lightning breakdown point and the process of line breakage are analyzed. Then, the lightning current energy is calculated to analyze. And various factors affecting the short-circuit current and the influence of short-circuit current on line breakage are studied in the PSCAD simulation model. Finally, based on the study on the mechanism of lightning-caused breakage of bare conductors, various protection measures are proposed to prevent disconnection of bare conductors. The study results in this paper can direct the protection strategy of line breakage and line tripping of 10kV distribution system.