Study on Lightning Protection of Shielding Failure for ± 500kV DC Transmission Line

To evaluate the protective performance of the side needle and negative shielding angle for overhead ground wire, the lightning protection of shielding failure of ±500kV DC transmission line is simulated in laboratory. The test results show that the side needle on the ground wire can reduce the probability of shielding failure, but the protection range is in a limited region along the line span; the negative shielding angle is better than the side needle.