1-wire bus DCearth fault on-line automatic monitoring apparatus

Abstract

The invention discloses a monobus DC grounding fault on-line automatic monitoring device used in an electric power DC power supply system and is characterized in that the device comprises a sensor connected between a plurality of DC branches and the bus, and an expansion interface circuit of the sensor; the sensor is connected on the monobus through the expansion interface circuit; the monobus is connected with a host which comprises a single-chip control circuit; a single chip of the single-chip control circuit is connected with a monobus interface circuit, an interbus voltage measurement circuit, a bus-to-ground voltage measurement circuit, a serial port expansion circuit, a clock calendar module, an E2PROM memory chip, a bus segment relay, an uneven grounding relay and an alarm contact relay, respectively; and the serial port expansion circuit is connected with a printer, a touch screen and an Ethernet module, respectively. The monobus DC grounding fault on-line automatic monitoring device can monitor the running status of the DC power supply system in a real-time way, as well as automatically and timely detect, accurately judge and display the running parameters of the fault branches; the device has the advantages of simple structure, low cost, as well as easy bus expansion and maintenance, which saves the I / O port line resources.

Description

technical field [0001] The invention relates to the technical field of control, and is an on-line automatic monitoring device for a single-bus DC grounding fault, which is applied to an electric DC power supply system to complete fault on-line monitoring. Background technique [0002] As an important part of the power system, the DC power supply system provides stable and reliable working power for substation relay protection and automatic devices, control signal loops, telecontrol communication devices and emergency lighting. Due to the complex wiring of the DC circuit, DC grounding is often caused by factors such as site dust, humidity, insulation aging, component damage, and irregular construction. After one point is grounded, because no loop is formed, the protection device will not malfunction. If the other point is also grounded if it is not handled in time, the device may malfunction, refuse to operate, or even damage the equipment, resulting in large-scale power outa...

AI Technical Summary

Problems solved by technology

Due to the complex wiring of the DC circuit, the DC grounding is often caused by factors such as dust, humidity, insulation aging, component damage, and irregular construction.

After one point is grounded, because no loop is formed, the protection device will not malfunction. If the other point is also grounded if it is not handled in time, the device may malfunction, refuse to operate, or even damage the equipment, resulting in large-scale power outages and DC power supply failures. Serious Consequences of a System Crash

At present, there is a certain gap between the technical principles adopted by various monitoring devices and the actual situation on site. The DC grounding search cannot be timely and accurately judged. The existing various monitoring devices are difficult to meet the needs of on-site online monitoring.

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