CN105571709A - Vibration sensor high temperature sensitivity absolute calibration method - Google Patents

Abstract

The invention provides an absolute calibration method for the high temperature sensitivity of a vibration sensor, which comprises the following steps: (1) setting a high temperature test chamber; (2) the vibration of the standard vibration table is transmitted to the vibration sensor to be calibrated in the high temperature test chamber through a vibration extension rod ; The vibration sensor in the high temperature test chamber feels the vibration signal of the standard vibration table and generates an analog electrical signal output to the data acquisition card, which is converted into a digital signal by the data acquisition card and input to the computer; (3) the light of the laser interferometer can be transmitted The glass window on the over-temperature test box shoots onto the vibration sensor to be calibrated; the laser interferometer measures the vibration level of the vibration sensor, outputs an analog electrical signal, converts it into a digital signal through the data acquisition card and inputs it into the computer; (4) computer calculation Vibration sensor high temperature sensitivity. The invention solves the problem that the vibration sensor cannot be calibrated in a high-temperature environment, and can realize absolute calibration of the high-temperature sensitivity of the vibration sensor.

Description

An Absolute Calibration Method for High Temperature Sensitivity of Vibration Sensor

technical field

The invention relates to the technical field of vibration measurement, in particular to an absolute calibration method for high temperature sensitivity of a vibration sensor.

Background technique

Vibration sensors are widely used in various links in the scientific research, production and testing process of national defense and military industry, and are responsible for monitoring and testing functions under various environmental conditions. It has been found through research that temperature changes have a great influence on the sensitivity of the vibration sensor. This is because most vibration sensors are composed of piezoelectric materials. According to the characteristics of piezoelectric materials, when it works outside the reference working temperature (room temperature), its output Charge sensitivity will vary greatly. The test error caused by the temperature in the high and low temperature environment cannot be ignored, and the sensitivity of the vibration sensor must be corrected during use.

At present, the calibration of the vibration sensor is carried out at room temperature, and the calibration method is to install the calibrated vibration sensor directly on the standard vibration table (as shown in Figure 1). Due to the narrow operating temperature range of the standard vibration table, It cannot work in a high and low temperature environment, and the calibration device cannot be placed in a high temperature test chamber as a whole, so the calibration method using this structural form cannot achieve vibration sensor calibration at high and low temperatures.

Contents of the invention

In order to solve the problem that the current vibration sensor cannot be calibrated in a high temperature environment, the present invention proposes an absolute calibration method for the high temperature sensitivity of the vibration sensor.

A technical solution for realizing the purpose of the present invention: an absolute calibration method for high temperature sensitivity of a vibration sensor, which includes the following steps:

(1) Temperature control: set up a high-temperature test chamber whose temperature can be controlled at 20°C to 800°C;

(2) Vibration measurement of the vibration sensor to be calibrated: the standard vibration table is set outside the high temperature test chamber, the vibration extension rod of the standard vibration table is placed in the high temperature test chamber, and the vibration sensor to be calibrated is placed in the high temperature test chamber and fixed at the standard vibration On the vibration extension rod of the table, the vibration of the standard vibration table is transmitted to the calibrated vibration sensor in the high temperature test chamber through the vibration extension rod; the vibration sensor in the high temperature test chamber senses the vibration signal of the standard vibration table and generates an analog electrical signal Output to the data acquisition card, convert it into a digital signal through the data acquisition card and input it into the computer;

(3) Laser interferometer vibration measurement: The laser interferometer is set outside the high-temperature test box, and the light of the laser interferometer can pass through the glass window on the high-temperature test box to the vibration sensor to be calibrated; adjust the laser interferometer so that The light is focused on the surface of the sensor, and the optical path is adjusted to cause interference; the laser interferometer measures the vibration level of the vibration sensor, outputs an analog electrical signal, and converts it into a digital signal through the data acquisition card and inputs it into the computer;

(4) Computer calculation: The computer calculates the high temperature sensitivity of the vibration sensor according to the output of the laser interferometer and the vibration sensor.

A method for absolute calibration of high temperature sensitivity of a vibration sensor as described above, the standard vibration table is connected to a power amplifier, the power amplifier is connected to a signal source, and the signal source is connected to a computer; the output voltage of the signal source or power amplifier is adjusted by the computer, according to the above steps (1) to step (4) measure the high temperature sensitivity of the vibration sensor, and the amplitude linearity of the sensitivity at high temperature can be obtained; adjust the output frequency of the signal source through the computer, and measure the sensitivity of the vibration sensor according to the above steps (1) to (4) , the frequency response of its sensitivity at high temperature can be obtained.

As described above, a vibration sensor high temperature sensitivity absolute calibration method, the temperature controller is connected to the relay, and the relay is connected to the electric heating wire arranged in the high temperature test chamber; the temperature controller is also connected to the thermocouple arranged in the high temperature test chamber; The controller sets the temperature value of the high-temperature test chamber, and the electric heating wire is controlled by the relay to heat the interior of the high-temperature test chamber; the temperature in the high-temperature test chamber is fed back by the thermocouple to the temperature controller, and it remains constant for 10 to 30 minutes after reaching the set temperature value .

The effect of the present invention is that: the present invention proposes an absolute calibration method for high-temperature sensitivity of a vibration sensor, which solves the problem that the vibration sensor cannot be calibrated in a high-temperature environment. The high-temperature sensitivity calibration of the vibration sensor is constructed by using this method, which can realize the absolute calibration of the high-temperature sensitivity of the vibration sensor.

Description of drawings

Figure 1 is a schematic diagram of the normal temperature calibration principle of the vibration sensor;

Fig. 2 is a schematic diagram of the principle of an absolute calibration method for high temperature sensitivity of a vibration sensor according to the present invention.

detailed description

A method for absolute calibration of high temperature sensitivity of a vibration sensor according to the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 2, the vibration sensor high temperature sensitivity absolute calibration method of the present invention, it comprises the following steps:

(1) Temperature control: set up a high-temperature test chamber whose temperature can be controlled at 20°C to 800°C; the temperature controller is connected to the relay, and the relay is connected to the electric heating wire in the high-temperature test chamber; the temperature controller is also connected to the high-temperature test chamber Set the thermocouple; set the temperature value of the high-temperature test chamber on the temperature controller, and heat the inside of the high-temperature test chamber through the electric heating wire controlled by the relay; the temperature in the high-temperature test chamber is fed back by the thermocouple to the temperature controller to reach the set temperature value (for example, 300 ° C) after 10 to 30 minutes (for example: 15 minutes);

(2) Vibration measurement of the vibration sensor to be calibrated: the standard vibration table is set outside the high temperature test chamber, the vibration extension rod of the standard vibration table is placed in the high temperature test chamber, and the vibration sensor to be calibrated is placed in the high temperature test chamber and fixed at the standard vibration On the vibration extension rod of the table, the vibration of the standard vibration table is transmitted to the calibrated vibration sensor in the high temperature test chamber through the vibration extension rod; the vibration sensor in the high temperature test chamber senses the vibration signal of the standard vibration table and generates an analog electrical signal Output to the data acquisition card, convert it into a digital signal through the data acquisition card and input it into the computer;

(3) Laser interferometer vibration measurement: The laser interferometer is set outside the high-temperature test box, and the light of the laser interferometer can pass through the glass window on the high-temperature test box to the vibration sensor to be calibrated; adjust the laser interferometer so that The light is focused on the surface of the sensor, and the optical path is adjusted to cause interference; the laser interferometer measures the vibration level of the vibration sensor, outputs an analog electrical signal, and converts it into a digital signal through the data acquisition card and inputs it into the computer;

(4) Computer calculation: the computer calculates the high temperature sensitivity of the vibration sensor according to the output of the laser interferometer and the vibration sensor;

(5) Continuous measurement: the standard vibration table is connected to the power amplifier, the power amplifier is connected to the signal source, and the signal source is connected to the computer; the signal source or the output voltage of the power amplifier is adjusted through the computer, and the high temperature of the vibration sensor is measured according to the above steps (1) to (4) Sensitivity, the amplitude linearity of the sensitivity at high temperature can be obtained; the output frequency of the signal source is adjusted by the computer, and the sensitivity of the vibration sensor is measured according to the above steps (1) to (4), and the frequency response of the sensitivity at high temperature can be obtained.

Claims (3)

1. A vibration sensor high temperature sensitivity absolute calibration method is characterized in that: the method comprises the steps: (1) Temperature control: set up a high-temperature test chamber whose temperature can be controlled at 20°C to 800°C; (2) Vibration measurement of the vibration sensor to be calibrated: the standard vibration table is set outside the high temperature test chamber, the vibration extension rod of the standard vibration table is placed in the high temperature test chamber, and the vibration sensor to be calibrated is placed in the high temperature test chamber and fixed at the standard vibration On the vibration extension rod of the table, the vibration of the standard vibration table is transmitted to the calibrated vibration sensor in the high temperature test chamber through the vibration extension rod; the vibration sensor in the high temperature test chamber senses the vibration signal of the standard vibration table and generates an analog electrical signal Output to the data acquisition card, convert it into a digital signal through the data acquisition card and input it into the computer; (3) Laser interferometer vibration measurement: The laser interferometer is set outside the high-temperature test box, and the light of the laser interferometer can pass through the glass window on the high-temperature test box to the vibration sensor to be calibrated; adjust the laser interferometer so that The light is focused on the surface of the sensor, and the optical path is adjusted to cause interference; the laser interferometer measures the vibration level of the vibration sensor, outputs an analog electrical signal, and converts it into a digital signal through the data acquisition card and inputs it into the computer; (4) Computer calculation: The computer calculates the high temperature sensitivity of the vibration sensor according to the output of the laser interferometer and the vibration sensor. 2. a kind of vibration sensor high temperature sensitivity absolute calibration method according to claim 1 is characterized in that: described standard vibrating table connects power amplifier, and power amplifier connects signal source, and signal source connects computer; Adjust signal source or by computer For the output voltage of the power amplifier, measure the high temperature sensitivity of the vibration sensor according to the above steps (1) to (4), and the amplitude linearity of the sensitivity at high temperature can be obtained; adjust the output frequency of the signal source through the computer, and follow the above steps (1) to Step (4) Measure the sensitivity of the vibration sensor, and the frequency response of the sensitivity at high temperature can be obtained. 3. A kind of vibration sensor high temperature sensitivity absolute calibration method according to claim 1 or 2, it is characterized in that: temperature controller is connected relay, and relay is connected with the electric heating wire that is located in the high temperature test chamber; Temperature controller is also connected high temperature The thermocouple installed in the test chamber; the temperature value of the high temperature test chamber is set in the temperature controller, and the electric heating wire is controlled by the relay to heat the inside of the high temperature test chamber; the temperature in the high temperature test chamber is fed back by the thermocouple to the temperature controller to achieve After setting the temperature value, keep it constant for 10 to 30 minutes.