Protection device of power supply line disconnection fault

Abstract

The invention provides a protection device of a power supply line disconnection fault, comprising a voltage-stabilizing circuit, a three-phase voltage sampling circuit, a three-phase voltage comparison circuit, a signal superimposed circuit and a split-phase pulse output circuit, wherein the output end of the three-phase voltage sampling circuit is connected with the three-phase voltage comparisoncircuit; and the output end of the three-phase voltage comparison circuit is connected with the split-phase pulse output circuit through the signal superimposed circuit. The protection device of thepower supply line disconnection fault is characterized in that a three-phase voltage-stabilizing circuit is used as the voltage-stabilizing circuit and is additionally provided with a grounding current control circuit, a blanking pulse circuit and a protection circuit, wherein the input end of the grounding current control circuit is connected with the split-phase pulse output circuit, and the output end of the same sequentially generates three-phase grounding current on the ground; and the blanking pulse circuit and the protection circuit are both connected with the grounding current controlcircuit. The invention utilizes the residual current of the front end of the grounding current control circuit to detect the tripping operation protection of the protection device after the power supply line disconnection fault is detected, and enables a system to have very simple structure and reliable property and provide protection for faults, i.e. zero line disconnection, phase line disconnection, extra-high voltage, extra-low voltage, and the like.

Description

technical field [0001] The invention provides a power supply line disconnection fault protection device, which belongs to the technical field of cable monitoring. Background technique [0002] The control mechanism in the power supply line is located at the front end of the line, there is no control mechanism in the middle and the end, which limits the detection and protection of zero break, phase break, overvoltage and undervoltage can only be installed at the front end of the power supply line and connected to the original Some control mechanisms trip to cut off the line power, but this method of detection at the front end of the line can only detect a few types of faults in the line, and most of the faults cannot be accurately detected at the front end of the line. If it is detected at the end of the line, all faults occurring in the line can be accurately detected, but there is no control mechanism to perform tripping protection. This contradiction has not been resolved ...

AI Technical Summary

Problems solved by technology

[0002] The control mechanism in the power supply line is located at the front end of the line, there is no control mechanism in the middle and the end, which limits the detection and protection of zero break, phase break, overvoltage and undervoltage can only be installed at the front end of the power supply line and connected to the original Some control mechanisms trip to cut off the line power, but this method of detection at the front end of the line can only detect a few types of faults in the line, and most of the faults cannot be accurately detected at the front end of the line

If it is detected at the end of the line, all faults in the line can be accurately detected, but there is no control mechanism to perform tripping protection. This contradiction has not been resolved in the prior art.

Images