Abstract:

The traveling wave method is currently a common approach for fault distance measurement in grounding electrode line, but it generally relies on simulation in terms of threshold setting, and cannot determine the type of grounding electrode line fault. To address the above issues, this paper adopts an active traveling wave injection method, and through analytical calculations, obtains the time-domain expression of the modulus-backward traveling wave at the measuring point at the first end of the ground electrode line after a single-line ground fault, a cross-line fault, a single-line open-circuit fault and a double-line open-circuit fault. A grounding electrode line fault type recognition and localization method is proposed based on modulus backward traveling wave. The proposed injection wave method has a clear expression of distance measurement threshold setting, then can accurately identify the type of line fault. The reliability and robustness of this method is verified in PSCAD/EMTDC simulations. Simulation results show that this method can achieve accurate fault distance measurement, and reliably identifies grounding electrode fault type, demonstrating strong tolerance to transition resistance and resistance to noise interference.

Key words: HVDC transmission, grounding electrode line, fault localization, fault type recognition, traveling wave method