Polarity clamping drainage device with adjustable threshold value

Abstract

The invention provides a threshold-adjustable polarity clamping drainage device which is connected between a buried long-distance pipeline and a grounding device so as to discharge direct-current stray current on the buried long-distance pipeline in a unidirectional polarity drainage mode. The circuit comprises a positive electrode end, a negative electrode end, a threshold value selection unit and a threshold value control unit. Wherein the positive electrode end and the negative electrode end are respectively connected with the buried long-distance pipeline and the grounding device through cables; the threshold selection unit is provided with an input end, a plurality of output ends and a selection part, the input end is electrically connected with the positive electrode end, and the selection part is used for selecting and controlling electrical conduction between the input end and each output end; the threshold value control unit is composed of a plurality of control modules with different threshold values, each control module is provided with an input end and an output end, the input ends of the plurality of control modules are correspondingly and electrically connected with the plurality of output ends, and the output ends of the plurality of control modules are electrically connected with the negative electrode end. Therefore, the drainage and discharge requirements of direct-current stray currents with different magnitudes borne by different positions of the buried long-distance pipeline can be met.

Description

technical field [0001] The invention relates to the technical field of cathodic protection of buried long-distance pipelines, in particular to a threshold-adjustable polarity-clamped discharge device capable of unidirectional polar discharge and discharge of DC stray currents received by buried long-distance pipelines . Background technique [0002] Buried long-distance transmission pipelines are often affected by interference sources such as high-voltage DC transmission lines along the line and its grounding electrodes, DC electrified railways, etc., so that the pipeline potential superimposes DC stray current on the basis of its own cathodic protection potential, resulting in the occurrence of pipeline potential. Positive or negative offset. When the pipeline potential is in a positive deviation for a long time and exceeds the minimum protection potential of cathodic protection, the corrosion rate of the pipeline will exceed the standard requirements, which will affect th...

AI Technical Summary

Problems solved by technology

However, due to the long length of the buried long-distance pipeline, along with the change of the distance between the pipeline and the interference source, there are differences and fluctuations in the potential offset value of the pipeline. Drainage protection requirements for pipelines with potential differences at different locations

For potential differences at different locations, although different single fixed threshold polarity drainage devices can be applied, as the pipeline potential fluctuates, the single fixed threshold polarity drainage device will not match for some time periods

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