阅读说明：本技术 一种氧气浓度传感器响应速度提升方法 (Method for improving response speed of oxygen concentration sensor ) 是由 王远 何子军 陈焱焱 汪兰兰 马祖长 孙怡宁 高理升 许杨 王翔 于 2019-12-27 设计创作，主要内容包括：本发明公开了一种氧气浓度传感器响应速度提升方法,用于提升氧气传感器测量响应速度,依据氧气传感器的阶跃响应特性,基于一个二阶微分函数算法来修正氧气浓度传感器输出信号,对氧气浓度传感器信号响应进行动态补充,进而提升测量系统中氧气浓度传感器响应时间速度。该方法利用数字软件方式提升了氧气浓度传感器的响应速度,为氧气浓度实时性测量提供了重要的技术支撑。(The invention discloses a method for improving the response speed of an oxygen concentration sensor, which is used for improving the measurement response speed of the oxygen sensor, correcting an output signal of the oxygen concentration sensor based on a second order differential function algorithm according to the step response characteristic of the oxygen sensor, dynamically supplementing the signal response of the oxygen concentration sensor and further improving the response time speed of the oxygen concentration sensor in a measurement system. The method utilizes a digital software mode to improve the response speed of the oxygen concentration sensor and provides important technical support for the real-time measurement of the oxygen concentration.)

1. A method for improving the response speed of an oxygen concentration sensor is characterized by comprising the following steps: according to the step response characteristic of the existing oxygen concentration sensor, a correction function of the oxygen concentration is constructed based on first-order and second-order differential functions, so that the response speed of the oxygen concentration output is improved.

2. The method of claim 1, wherein the method comprises: the correction function of the oxygen concentration sensor can be described as follows:

K₁＝τ/3

K₂＝τ/2

wherein Z (t) is the corrected oxygen concentration output, γ (t) is the pre-correction oxygen sensor output, K₁、K₂Is constant, and tau is the sensor step response time constant, and can be obtained by performing step response test on the sensor.

3. The method of claim 2, wherein the method comprises: the step response time constant test method comprises the following steps:

(1) existing oxygen sensor concentrations vary from 0 to gamma_fThe step response characteristic of (a) may be expressed as:

γ(t)＝γ_f(1-e^-kt)

(2) measuring the time T from 10% to 90% of the output concentration variation value of the sensor_10-90Then, the response time constant τ is known:

thereby obtaining

Technical Field

The invention relates to the technical field of oxygen sensors, in particular to a method for improving the response speed of an oxygen concentration sensor.

Background

With the development of science and technology, the development and application of oxygen sensors are developed, and the analysis and measurement of oxygen are widely applied to many fields such as laboratories, biology, medicine, automobile manufacturing, chemical engineering, energy and the like. However, most of the existing oxygen sensors are electrochemical sensors, have long response time and cannot meet the requirement of on-line real-time concentration acquisition.

Disclosure of Invention

The invention aims to solve the technical problems and provides a method for improving the response speed of an oxygen concentration sensor, which solves the problem of long response time.

The technical scheme adopted by the invention is as follows: a method for improving the response speed of an oxygen concentration sensor constructs a correction function of oxygen concentration based on first-order and second-order differential functions according to the step response characteristic of the existing oxygen concentration sensor, so that the response speed of oxygen concentration output is improved.

Further, the correction function of the oxygen concentration sensor may be described as follows:

K₁＝τ/3

K₂＝τ/2

wherein Z (t) is the corrected oxygen concentration output, γ (t) is the pre-correction oxygen sensor output, K₁、K₂Is constant, and tau is the sensor step response time constant, and can be obtained by performing step response test on the sensor.

Further, the step response time constant test method is as follows:

(1) existing oxygen sensor concentrations vary from 0 to gamma_fThe step response characteristic of (a) may be expressed as:

γ(t)＝γ_f(1-e^-kt)

(2) measuring the time T from 10% to 90% of the output concentration variation value of the sensor_10-90Then, the response time constant τ is known:

thereby obtaining

The invention has the beneficial effects that:

(1) on the basis of the traditional oxygen sensor measurement, the invention introduces a concentration correction function to compensate the error caused by the oxygen concentration response speed, improves the response speed of the oxygen sensor through digital software, and reduces the error of real-time oxygen concentration analysis.

(2) The model established by the invention provides reference for improving the response speed of the gas sensor.

Drawings

FIG. 1 is a schematic diagram of a rapid oxygen concentration acquisition method of the present invention;

FIG. 2 is a step response characteristic of an oxygen sensor;

FIG. 3 is a correction function of K₂And (4) supplementing effects corresponding to different values.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Most of the existing oxygen concentration analysis sensors on the market are electrochemical principles, the reaction time is more than hundred milliseconds, and the requirements of some real-time dynamic oxygen concentration detection application scenes cannot be met, so that a correction function containing first-order and second-order differentials is constructed by utilizing the step response characteristic of the oxygen concentration sensor, as shown in fig. 1, the error caused by reaction delay on detection can be compensated, the accuracy of oxygen real-time detection is improved, and the specific method and the steps are as follows:

first, the step response characteristics of the oxygen concentration sensor can be well fitted with the following single exponential function, as shown in fig. 2, where the dashed line is the measured step response of the oxygen sensor and the solid line is the function-fitted curve.

γ(t)＝γ_f(1-e^-kt) (1)

Where k can be obtained directly from the measured curve:

then, a correction function is constructed by utilizing the first order differential and the second order differential, and is used for correcting the sensor concentration output:

wherein:

substituting (4) and (5) into the correction function (3) can obtain:

Z(t)＝-(kK₁-1)(kK₂-1)γ_fe^-kt+γ_f(6)

let K₁＝τ/3，K₂The corresponding corrected step response characteristic curves after taking 0.1 tau, 0.3 tau, 0.5 tau, 0.8 tau, tau and 1.2 tau are shown in fig. 3, and it can be seen that the step response characteristic of the oxygen sensor can be obviously improved by the correction function, K₂When 0.5 tau is taken, the dynamic response characteristic of oxygen can be obviously improved. Therefore, the oxygen concentration can be corrected by the formula (3) in the oxygen concentration test process, and the real-time response speed of oxygen is improved.