A Lightning Stroke Identification Method For Hvdc Transmission Line Protection

Lightning strokes may make traveling wave protection work incorrectly and lightning recognition method is important. The voltage initial travelling waves (VITW) at measured point and corresponding waveform characteristics are derived for lightning faults, lightning disturbance and internal faults conditions respectively. Based on the waveform characteristics, a lightning identification method for HVDC transmission line protection is proposed in this paper. The degree of dispersion of VITW is utilized to distinguish the lightning disturbance on transmission line from faults. A ± 800 kV HVDC system simulation model, including detailed lightning stroke simulation model, is built in PSCAD/EMTDC. Simulation results show that the proposed lightning stroke identification method can distinguish disturbances from faults correctly with ultra-high-speed, providing a strong guarantee for main protection to prevent the mal-operation in the case of disturbance.