Insulation monitoring device with voltage deviation compensation and voltage deviation compensation method thereof

Abstract

The invention relates to a pressure difference adjustment device for an insulation monitoring device, in particular to an insulation monitoring device with voltage deviation compensation, which includes a balance bridge circuit and a compensation circuit. The compensation circuit includes a positive compensation triode and a negative compensation triode, and the collector of the positive compensation triode Connect to the positive pole of the DC bus, the emitter is connected to the ground wire through the current limiting resistor R3, the collector of the negative compensation transistor is connected to the ground wire, the emitter is connected to the negative pole of the DC bus through the current limiting resistor R4, and the bases of the positive and negative compensation transistors are respectively The current-limiting resistor R5 and the current-limiting resistor R6 are connected to the switching switch, and the switching switch is connected to the control unit to realize accurate compensation for the voltage deviation of the DC system to the ground. The invention provides a voltage deviation compensation method, which realizes the smooth control of the magnitude of the current between the collector and the emitter, ensures the safe operation of the DC system, and eliminates potential safety hazards.

Description

technical field [0001] The invention relates to a pressure difference adjusting device of an insulation monitoring device, in particular to an insulation monitoring device with voltage deviation compensation and a voltage deviation compensation method thereof. 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 g...

AI Technical Summary

Problems solved by technology

[0003] The DC insulation monitoring device can only detect the insulation degradation of the DC system, but when the DC system has a single-pole or two-pole insulation degradation, if the voltage deviation of the DC system to the ground is too large, even if the insulation resistance to the ground does not decrease to the level of the insulation alarm There will be hidden dangers to the safe operation of the DC system

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