Instant alternating current invasion prevented insulation monitoring device

Abstract

The invention relates to insulation monitoring of a direct current system, and particularly relates to an instant alternating current invasion prevented insulation monitoring device. The device comprises a host, a wire selection device and a direct current leakage current sensor, wherein the host comprises a CPU data processing module, a data collection module, a balance bridge and unbalanced bridge circuit module, a power supply module, a display module, an alarm module and a communication module; the CPU data processing module is connected with the data collection module; the data collection module comprises a multi-channel collection electronic switch, an operational amplifier and a high-precision AD chip, and is used for collecting positive and negative earth grounded voltage of a direct current bus and voltage of the direct current bus in real time; the balanced bridge and unbalanced bridge circuit module comprises a group of balanced bridge resistor and a detection bridge resistor; the display module and the alarm module are connected with the CPU data processing module; and the wire selection device is connected with the CPU data processing module and the direct current leakage current sensor.

Description

technical field [0001] The invention relates to insulation monitoring of a DC system, in particular to an insulation monitoring device for preventing instantaneous AC intrusion. Background technique [0002] The safe and reliable operation of DC power supply is very important for the safe and reliable operation of substations. However, due to the large number of DC power supply devices and long power supply cables, faults such as DC grounding often occur in actual operation. Although the DC system runs floating, the single-point grounding does not affect the normal operation of the system, but the fault must be found and eliminated as soon as possible, otherwise, when the second point grounding occurs, the relay or protection device will malfunction and cause serious consequences. At present, DC system insulation and line selection devices are widely used in substations, which have achieved good results. [0003] In actual operation, there is a special ground fault that is...

AI Technical Summary

Problems solved by technology

The insulation monitoring devices of most manufacturers still do not have the function of measuring and alarming AC intrusion faults, and the monitoring devices with this function generally have a longer response time to AC intrusion faults

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