Pipe-to-soil potential excessively-negative control method and device for buried pipeline

Abstract

The invention relates to a pipe-to-soil potential excessively-negative control method and device for a buried pipeline which suffers from DC spurious emission interference. A voltage reference source is used as a signal collecting comparison and triggering control circuit to trigger and control a based threshold value; when the pipe-to-soil potential collected by the signal collecting comparison and triggering control circuit A02 exceeds the specified value of the threshold value, an operational amplifier in the circuit outputs in the forward direction, a photoelectric coupler is triggered and connected, and a reverse compensation control circuit A03 is triggered to start applying a forward current to the pipeline; when the pipe-to-soil potential collected by the signal collecting comparison and triggering control circuit A02 has already returned within the allowed range of the set threshold value, the operational amplifier is free of output, the photoelectric coupler is not triggered, optoelectronic isolation takes effect, trigger control is canceled, and the reverse compensation control circuit A03 stops working. The pipe-to-soil potential excessively-negative phenomenon due to the fact that the pipeline suffers from DC interference is avoided, and the hydrogen brittleness and coating stripping danger of the pipeline can be eliminated.

Description

technical field [0001] The invention relates to a control method and device for solving the over-negative potential of buried pipelines suffering from direct current stray interference. It relates to the technical field of piping systems. Background technique [0002] In recent years, with the high-speed construction of urban express rail, high-voltage direct current transmission lines and oil and gas pipelines, there are more and more crossing and parallel phenomena between them and buried oil and gas pipelines, and energy "public corridors" are becoming more and more common. However, the electric field environment, abnormal working conditions and grounding settings of the DC transmission line, as well as the light rail system with DC as the excitation source, will cause DC stray current interference to its adjacent buried steel pipelines. Stray current interference source) in the area where the pipe-ground potential shifts positively to cause corrosion, while in the area ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to invent a method and device for controlling the over-negative potential of the buried pipeline, which prevents the over-negative potential of the pipeline from being subjected to direct current interference and solves the risk of hydrogen embrittlement and coating peeling of the pipeline.

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