DC parasitic loop detection system and method

Abstract

The invention relates to a DC parasitic loop detection system and method. The system comprises a first detection device and a second detection device. The first detection device is used for injecting a characteristic signal to a to-be-detected branch circuit of the DC system and collecting a first current signal of a to-be-detected node on the to-be-detected branch circuit, and the first current signal is obtained by the first detection device according to the characteristic signal. The second detection device is used for collecting second current signals of at least two nodes between the characteristic signal injection node and the to-be-detected branch circuit load when the first current signal is not zero, and determining a suspicious parasitic loop branch circuit according to each second current signal; and the second detection device is further used for collecting a third current signal on the suspicious parasitic loop branch circuit, and determining a parasitic loop according to each second current signal and the third current signal. According to the parasitic loop detection system, the fault point positioning precision in the parasitic loop fault detection process can be improved.

Description

technical field [0001] The present application relates to the technical field of DC parasitic loop detection, and in particular to a DC parasitic loop detection system and method. Background technique [0002] The safe operation of the DC system is the guarantee of the protection and control system of the substation and the lifeline for the relay protection equipment to play a normal role. Its importance is self-evident. A major hidden danger in the DC system is the parasitic loop. The parasitic circuit will generate circulating current, which will not only affect the judgment of the DC system insulation monitoring device on the insulation fault of the feeder branch, but also lead to incomplete power outage of the load and affect equipment maintenance. [0003] The traditional parasitic loop detection system measures the negative-to-ground voltage by connecting a bias resistor between the negative-to-ground of the DC bus, and determines whether there is a parasitic loop acc...

AI Technical Summary

Problems solved by technology

[0005] Based on this, it is necessary to address the above technical problems and provide a DC parasitic loop detection system and method to solve the problem of poor parasitic loop fault location in the traditional DC parasitic loop detection process

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