A detection device and method for micro-current of multi-electrode array corrosion sensor

Abstract

The invention relates to a detection device and method for multi-electrode array corrosion sensor micro current. The detection device consists of a corrosion array connection circuit, an electronic changeover switch circuit, a current-to-voltage amplifying circuit, a voltage conversion circuit within AD range and a single chip microcomputer control and sampling system that are connected in order. The single chip microcomputer control and sampling system is connected to the current-to-voltage amplifying circuit through an operational amplifier input offset voltage cancelling circuit, and is also connected to the electronic changeover switch circuit, and the electronic changeover switch circuit and the current-to-voltage amplifying circuit are also connected to a negative voltage conversion circuit simultaneously. Therefore, the device and the method provided by the invention have the advantages that: 1. DAC is utilized to eliminate the offset voltage of operational amplifier; and 2. real-time switching comparison is carried out to improve the measurement accuracy.

Description

technical field [0001] The invention relates to the field of circuits, in particular to a detection device and method for the tiny current of a multi-electrode array corrosion sensor. Background technique [0002] In most cases, metal corrosion is an electrochemical process, that is, the metal dissolves to release electrons (anodic reaction), and other environmental media such as oxygen receive electrons (cathode reaction). This anodic reaction and cathodic reaction occur simultaneously at different locations on the metal surface, exchanging electrons through the metal itself, a good conductor. As this electron exchange process continues across the entire metal surface, once a sufficiently large area becomes anodic, corrosion will focus on that area. The electronic method, that is, the detection of metal corrosion by measuring the flow of electrons is more sensitive and effective than other methods, but because the flow of electrons occurs inside the metal, it cannot be dir...

AI Technical Summary

Problems solved by technology

For the array electrode, how to accurately measure the tiny corrosion current requires the design of an amplifying circuit that meets the current-to-voltage conversion. Since the corrosion current is very small, it is difficult for the conventional current-to-voltage circuit to meet the requirements of uA level current measurement.

Although the existing technology solves the measurement of single galvanic corrosion current, it is not suitable for the measurement of array corrosion current

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