Method for extracting property of gas sensor output, and device and method for measuring gas density using it

Abstract

The invention relates to an extracting method for gas sensor output characteristic and a gas concentration measuring device using the extracting method and a method thereof, comprising: process of respectively measuring output voltages of two ends of load resistor corresponding to internal resistance of each gas sensor and each gas concentration, selecting a maximal voltage regulation from calculated output voltage regulation changing along time, in order to extract gas sensor output characteristic data; process of obtaining a characteristic relation formula among the gas concentration, the internal resistance of gas sensor and the maximal voltage regulation via using obtained gas sensor output characteristic data; process of using characteristic relation formula of the maximal voltage regulation to measure gas concentration. The output characteristic of the gas sensor according to the invention is relative to the gas concentration and internal resistance of the gas sensor, thus, the invention can be used for function evaluation for gas concentration measuring device and gas sensor.

Description

technical field [0001] The invention relates to a method for extracting the output characteristics of a gas sensor that accurately extracts the output characteristics of a gas sensor by measuring the maximum voltage change rate, and calculating the output voltage change rate of the gas sensor, from which the maximum voltage change rate is found and calculated. Gas concentration, a gas concentration measuring device and a method for displaying the calculation result thereof. Background technique [0002] With the continuous improvement of industrialization and urbanization in modern society, the sources of environmental pollution are also expanding. Faced with this situation, people continue to deepen their research on environmental technology and increase their investment in the environmental industry market. In order to detect and prevent harmful gases from environmental pollution sources in time, people have continuously improved the functions of semiconductor gas sensors...

AI Technical Summary

Problems solved by technology

[0010] However, using the above-mentioned output value before injecting gas into the gas sensor (V air , R air ) and the output value after gas injection (V gas , R gas , R x ) to evaluate the function of the gas sensor, the initial output value will change with the measurement environment, resulting in unstable output results, so that the function of the gas sensor cannot be evaluated objectively

Moreover, since it is difficult to ensure that the resistance of all gas sensors is exactly the same during the manufacturing process, the output characteristics of each gas sensor are also different.

That is, the output value ratio formula before and after gas injection produces various results, so a unified function evaluation method cannot be used

In addition, when the gas to be measured is repeatedly injected at a fixed cycle, the output value of the gas sensor varies from moment to moment, so the reproducibility of sensitivity, which is a necessary condition of the gas sensor, is significantly reduced.

[0011] The output characteristics of semiconductor gas sensors mainly depend on the initial resistance R of the gas sensor S and the concentration C of the injected gas, however, in the above method using the initial resistance R S and gas concentration C fail to clearly describe its output characteristics

Moreover, although it is known at the time of manufacture that the initial resistance R S value, and the gas concentration C value can be estimated by analyzing the output signal of the gas sensor. However, because there is no clear definition of the output characteristics, it is also inconvenient to estimate the gas concentration.

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