Metro stray current drainage device

Abstract

The invention relates to a metro stray current drainage device which comprises a drainage incoming terminal, a bus bar, a control circuit and a drainage circuit, wherein the control circuit comprisesa signal collection circuit, a micro-controller and an IGBT driving circuit. When in use, the potential of a structural reinforcing bar with a drainage net and the potential of a reference electrode are collected in a real-timer manner, the difference between the two potentials is obtained through the micro-controller, the difference is compared with the reference voltage, when the comparison value is greater than 0.5V, the duty ratio of an IGBT which needs to be changed is figured out by a program in the micro-controller according to the rand-size relationship of the difference between the comparison value and the 0.5V, a control signal for changing is emitted, and the duty ratio of the IGBT is changed through the IGBT driving circuit, thereby automatically changing the resistance of a current-limiting resistor, leading the metro stray current drainage device to drain timely and effectively, reducing the harm of stray current to the lowest level, protecting the safe operation of a metro and effectively reducing the corrosion of the stray current to the structural reinforcing bars along the metro.

Description

technical field [0001] The invention relates to a subway stray current drainage device. Background technique [0002] In subways all over the world, direct current is generally used as the power supply of subway vehicles, and most of them use running rails as the return channel of traction current. With the prolongation of the use time of the subway, the metal dust generated by the friction between the vehicle and the rail is under the action of the underground humid environment, so that the insulation resistance between the rail and the earth is continuously reduced, causing a part of the traction return current to flow to the earth to form a stray current. (Also known as "stray flow"). Stray currents will cause electrochemical corrosion when flowing through underground metal structures, especially for oil pipelines, gas pipelines, tap water pipelines and structural steel of buildings along the subway line. [0003] At present, the protection measures for stray current ge...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problems that the existing subway stray current draining device cannot timely and effectively drain the current, thereby affecting the safe operation of the subway and causing corrosion to various metal pipes and structural steel bars along the subway, the present invention provides a subway stray current drainage device. current drain

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