DC system insulation monitoring device

Abstract

The invention relates to the field of electric power DC power supply monitoring devices, and particularly relates to a DC system insulation monitoring device installed in a transformer substation. TheDC system insulation monitoring device is characterized by comprising a system insulation monitoring bridge, a bridge signal processing loop, an A / D circuit 1, a CPU 1, an AC creepage monitoring unit, an AC creepage signal processing loop, an A / D circuit 2, a CPU 2, a DC mutual creepage monitoring unit, a DC mutual creepage signal processing loop, an A / D circuit 3, a CPU 3, a storage battery loopmonitoring unit, a storage battery monitoring signal processing loop, an A / D circuit 4, a CPU 4, a leakage current transformer, a leakage current signal processing loop, an A / D circuit 5, a CPU 5, aDSP unit, a displayer, a keyboard and control circuit, an alarm indicating lamp, an alarm output contact, an upper computer communication interface and a working power supply module, etc. The device is used for transformer substation DC power supply monitoring so that rapid search in case of failure of the equipment can be realized, the labor intensity of the maintenance personnel can be reduced,time and labor can be saved and the working efficiency, the power supply reliability and the economic benefit of the electric power enterprise can be enhanced.

Description

technical field [0001] The invention relates to a DC system insulation monitoring device, which belongs to the field of electric DC power monitoring devices. Background technique [0002] The DC power system in the power system is an ungrounded power system, which mainly provides working power for the relay protection equipment, automation equipment, communication equipment, and high-voltage switch operation of the substation. A ground fault in the DC power system will cause relay protection errors. In severe cases, it may even cause a power outage accident, so the substation has higher requirements for the insulation monitoring of the DC power system. There are many types of ground faults, such as grounding caused by protection device failure, grounding caused by cable damage, grounding caused by water ingress in equipment, grounding caused by AC crossing into DC, and mutual crossing of different power sources. The grounding caused by the leakage of the battery pack, etc.,...

AI Technical Summary

Problems solved by technology

There are many types of ground faults, such as grounding caused by protection device failure, grounding caused by cable damage, grounding caused by water ingress in equipment, grounding caused by AC crossing into DC, and mutual crossing of different power sources. The grounding caused by the leakage of the battery pack, etc., may cause a ground fault in the DC system, and may also be multi-point grounding, high-impedance grounding, etc.

[0003] Due to the variety of DC system grounding types, miscellaneous phenomena, wide distribution of DC power supply systems, many branch circuits, and difficulty in finding and locating grounding, a DC system insulation monitoring device is designed to meet the actual safe operation requirements of substations.

Images