Loop Fault Monitoring System for Multiple Bus Sections in DC System

Abstract

The invention discloses a system for monitoring a fault of a loop on a multi-bus section of a direct current system. The system for monitoring the fault of the loop on the multi-bus section of the direct current system comprises a signal acquisition and preprocessing module (SCM), a signal analysis and processing module (SAM) and a loop fault warning module (LWM), wherein the SCM comprises a high-precision direct-current leakage current sensor, a band-pass filtering circuit, a signal amplifying device, an impedance conversion circuit, a high-precision AD converter, a CPU, an active filter circuit, a high-impedance input emitter follower and an active filter circuit, FIR digital signal preprocessing is conducted on collected data by the SAM, and a wavelet time-domain frequency spectrum is extracted after noise is filtered out and is matched with various loop models arranged in equipment; the LWM comprises a fault analysis meter, an acousto-optic driving instrument, a liquid crystal displayer, a direction displayer, an impedance displayer and a waveform displayer. According to the system for monitoring the fault of the loop on the multi-bus section of the direct current system, the problem that the fault of the loop of the direct current system can not be monitored and handled effectively at present is solved, non-planed stopping of the equipment due to protection maloperation or lack of protection operation caused by long-term existing of the fault is avoided, and safety and reliability of a secondary direct-current power supply system are guaranteed.

Description

[0001] Technical field: [0002] The invention relates to a fault detection system, in particular to a multi-bus section loop fault monitoring system of a direct current system, which belongs to the technical field of grounding faults of a direct current system. [0003] Background technique: [0004] Grounding of DC systems in power plants and substations is a common fault that is very harmful to power systems. Under normal circumstances, one-point grounding does not affect the operation of the DC system, but if the ground fault point cannot be quickly found and repaired, and another point ground fault occurs, it may cause malfunctions of signal circuits, control circuits, relay protection and other devices , thus destroying the safe operation of the power system, and even causing large-scale power outages. Therefore, when a little ground fault occurs in the DC system, it must be detected and eliminated as early as possible. [0005] At present, the insulation analysis of th...

AI Technical Summary

Problems solved by technology

However, for the loop between multi-section buses, it is impossible to effectively pair, especially the search for loop points, and there is still a lack of effective search tools or instruments

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