Pilot protection method and system, storage medium and computing equipment

Abstract

The invention discloses a pilot protection method and system, a storage medium and computing equipment, and the method comprises the steps: calculating the high-frequency transient components of a backward voltage traveling wave A and each backward voltage traveling wave B under the conditions that a DC cable has a fault and one DC bus is connected with a plurality of DC cables, thereby judging the fault direction of the DC cable, and achieving the fault protection of the DC cable. Compared with traditional pilot protection, only directional signals are sent, data synchronization is not needed, the difficulty of actual implementation is greatly reduced, and the protection method is not affected by distributed capacitance current and traveling wave aliasing, is more suitable for an MVDC power distribution system, and can be applied to the MVDC power distribution system. The method does not depend on the boundary of the line terminal (such as an electric reactor installed on the line terminal), and is more in line with the topological structure characteristics of the MVDC power distribution system.

Description

technical field [0001] The invention relates to a longitudinal protection method, system, storage medium and computing equipment, and belongs to the field of relay protection of direct current transmission systems. Background technique [0002] DC power distribution level longitudinal protection is one of the key technologies in the development of DC systems. For the case where a DC bus is connected to multiple DC cables, it can identify and protect internal faults and protect external faults. The existing DC distribution-level longitudinal protection is mainly designed for low-voltage DC applications. Since the cable length is very short, the influence of distributed capacitive current can be ignored. In the MVDC power distribution system, due to the increase of the cable length, the distributed capacitive current cannot be ignored, and the topology of the distribution network system is more complex, and the DC reactor (for fault current limitation) is more likely to be ins...

AI Technical Summary

Problems solved by technology

In the MVDC power distribution system, due to the increase of cable length, the distributed capacitive current cannot be ignored, and the topology of the distribution network system is more complex, and the DC reactor (for fault current limitation) is more likely to be installed only at the outlet of the converter station, and cannot Provides clear line boundaries, so existing longitudinal protection is not suitable for MVDC power distribution systems

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