CN104502998B - Characteristic parameter tester and testing method for seismic detector - Google Patents

Abstract

A geophone characteristic parameter tester and testing method, the tester includes a temperature sensor, a signal board and a computer, the signal board is provided with a connected signal acquisition card and a constant current source, the temperature sensor is attached to the geophone, and the geophone outputs The output end of the temperature sensor is connected with the input end of the signal acquisition card, the output end of the signal acquisition card is connected with the input end of the computer, the output end of the computer is connected with the input end of the signal acquisition card, the output end of the signal acquisition card is connected with the input end of the constant current source The output terminal of the constant current source is connected to the input terminal of the detector; the test method adopts the sine sweep constant current excitation method to excite the detector, collects the response signal of the detector, and obtains the detector through the algorithm of taking the real part of the frequency response function The characteristic parameters of the geophone; the measurement range of the characteristic parameters of the geophone is broadened, not only the characteristic parameters of the underdamped geophone, but also the characteristic parameters of the overdamped geophone can be measured; the precision and accuracy of the geophone parameter test are improved.

Description

Geophone Characteristic Parameter Tester and Test Method

technical field

The invention relates to the technical field of geophone characteristic parameter testing, in particular to a geophone characteristic parameter tester and a test method.

Background technique

The moving coil geophone is widely used in geophysical exploration and seismic research. The accurate and convenient measurement of its characteristic parameters is very important to ensure the quality of exploration data.

At present, instruments at home and abroad based on the electric excitation method to measure the characteristic parameters of the moving coil detector (such as Sensor's SMT series SMT-200, SMT-400 and some domestic related test instruments) all use the DC excitation method, that is, use The time domain curve and the relationship between various parameters are used to solve the characteristics of the geophone, but this DC excitation method is only suitable for the measurement of underdamped geophones, and cannot be used for parameter testing of large damped geophones. It can measure the types of geophones limited, and has the disadvantages of low measurement accuracy and poor repeatability of multiple measurements. Therefore, it is necessary to find a new parameter identification algorithm and develop a test instrument that implements this algorithm to improve the test accuracy and broaden the types of measurable geophones. , to improve the repeatability of multiple measurements.

Contents of the invention

In order to overcome the problems in the above-mentioned prior art, the object of the present invention is to provide a geophone characteristic parameter tester and testing method, which improves the measurement range of geophone parameter testing, not only can measure underdamped geophone characteristic parameters, but also The characteristic parameters of the over-damped geophone can be measured; the precision and accuracy of the geophone parameter test are improved.

In order to realize the above-mentioned purpose of the invention, the technical scheme that the present invention takes is:

The geophone characteristic parameter tester includes a temperature sensor 2, a signal board 3 and a computer 4, the signal board 3 is provided with a connected signal acquisition card 3-1 and a constant current source 3-2, and the temperature sensor 2 is attached to the geophone On 1, the output end of detector 1 and the output end of temperature sensor 2 are connected with the input end of signal acquisition card 3-1, and the output end of signal acquisition card 3-1 is connected with the input end of computer 4, and the input end of computer 4 The output end is connected with the input end of the signal acquisition card 3-1, the output end of the signal acquisition card 3-1 is connected with the input end of the constant current source 3-2, and the output end of the constant current source 3-2 is connected with the detector 1 connected to the input.

The temperature sensor 2 adopts a PP1000 thermal resistance temperature sensor.

The signal acquisition card 3-1 is an M series data acquisition card of National Instruments NI.

The method for testing the characteristic parameters of the geophone by the above-mentioned geophone characteristic parameter tester, the computer 4 outputs the sine sweep signal to the signal acquisition card 3-1, and the signal acquisition card 3-1 collects the sine sweep signal The frequency signal is output to the constant current source 3-2, and the constant current source 3-2 converts the sinusoidal frequency sweep signal into a constant amplitude sinusoidal frequency sweep signal, and outputs the constant amplitude sinusoidal frequency sweep signal to the detector 1 , the geophone 1 responds to the sine frequency sweep signal and outputs the signal to the signal acquisition card 3-1, and the temperature sensor 2 outputs the temperature signal of the geophone 1 collected to the signal acquisition card 3-1 simultaneously, and the signal acquisition card 3-1 will The two-way signals are output to the computer 4, and the computer 4 obtains the detector characteristic parameters through calculation; the specific calculation method is as follows:

Step 1: Obtain the first zero-crossing point of the phase-frequency curve through the frequency response function (3), and determine the natural frequency f ₀ ;

Among them: H(f) is the frequency response function of the detector, f is the frequency, R is the series resistance value of the circuit where the detector is located, R _c is the DC resistance of the detector, L _c is the equivalent inductance of the detector, S ₀ is The open-circuit sensitivity of the geophone, f ₀ is the natural frequency of the geophone, ζ ₀ is the damping ratio of the geophone, and M is the mass of the moving coil of the geophone;

Step 2: Connect the DC signal I to the circuit composed of the detector 1 and the resistor R in series, and measure the voltage values at both ends of the resistor R and the detector 1, which are expressed as U _in and U _out respectively, to obtain That is, the DC resistance value of detector 1;

Step 3: Take the real part of the frequency response function (3) and ignore the influence of the inductance to obtain formula (4);

When f = f ₀ ,

when hour,

Let a=R·H _re (f ₀ )-R _c (7)

get,

make

get,

First, the values of a and b are obtained from the frequency response function (3), and by Obtain the damping ratio ζ ₀ of the geophone, and then by The sensitivity S ₀ of the detector is obtained, and the dynamic resistance is defined as the impedance value of the detector when f=f ₀ and the influence of the inductance is neglected, Therefore, the dynamic resistance R _d =R·H(f ₀ );

Through the above calculation process, the characteristic parameters of the geophone 1 are obtained: natural frequency f ₀ , DC resistance value R _c , damping ratio ζ ₀ , open circuit sensitivity S ₀ and dynamic resistance R _d .

Compared with the prior art, the present invention has the following advantages:

1) The measuring instrument of the present invention has improved the measurement scope of geophone parameter test, not only can measure the characteristic parameter of underdamped geophone, but also can measure the characteristic parameter of overdamped geophone; Improve the precision and accuracy of geophone parameter test, Compared with the previous geophone tester, the test accuracy is higher, and the data jump of repeated measurement results is small, which ensures the accuracy of the measurement; it is smaller and more portable than the previous geophone tester.

2) The test method of the present invention improves the recognition range of the geophone parameter identification algorithm, not only can identify the characteristic parameters of the underdamped geophone, but also can identify the characteristic parameters of the overdamped geophone; the accuracy and accuracy of the geophone parameter identification are improved Compared with the previous identification method of geophone characteristic parameters, the test accuracy is higher, the error is smaller, and the speed is faster.

Description of drawings

Fig. 1 is a schematic structural diagram of the tester of the present invention.

Figure 2 is a circuit composed of a detector and a resistor R connected in series, where detector 1 is between CDs.

detailed description

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the geophone characteristic parameter tester of the present invention comprises a temperature sensor 2, a signal board 3 and a computer 4, and a connected signal acquisition card 3-1 and a constant current source 3-2 are arranged in the signal board 3 , the temperature sensor 2 is attached to the wave detector 1, the output end of the wave detector 1 and the output end of the temperature sensor 2 are connected with the input end of the signal acquisition card 3-1, and the output end of the signal acquisition card 3-1 is connected with the computer 4 The input end is connected, and the output end of computer 4 is connected with the input end of signal acquisition card 3-1, and the output end of signal acquisition card 3-1 is connected with the input end of constant current source 3-2, and constant current source 3- The output terminal of 2 is connected with the input terminal of detector 1.

As a preferred embodiment of the present invention, the temperature sensor 2 adopts a PP1000 thermal resistance temperature sensor for measuring the ambient temperature where the detector is located, and by adding temperature compensation, the currently measured parameters are uniformly converted into values at a temperature of 20°C , thereby excluding the influence of temperature on the detector parameters.

As a preferred embodiment of the present invention, the signal acquisition card 3-1 is an M-series data acquisition card of National Instruments, Inc. of the United States.

As shown in Figure 2, the geophone characteristic parameter tester of the present invention carries out the method for geophone characteristic parameter test, and described computer 4 outputs sinusoidal sweep signal and outputs to signal acquisition card 3-1, and signal acquisition card 3-1 1 Output the collected sinusoidal frequency sweep signal to the constant current source 3-2, and the constant current source 3-2 converts the sinusoidal frequency sweep signal into a constant amplitude sinusoidal frequency sweep signal, and converts the constant amplitude sinusoidal sweep signal The frequency signal is output to the detector 1, and the detector 1 responds to the sine frequency sweep signal and outputs the signal to the signal acquisition card 3-1, and the temperature sensor 2 outputs the temperature signal of the detector 1 collected to the signal acquisition card 3-1 simultaneously. The signal acquisition card 3-1 outputs the two-way signals to the computer 4, and the computer 4 obtains the detector characteristic parameters through calculation; the specific calculation method is as follows:

Step 1: First, a resistor R is connected in series to the detector 1, and the current I is controlled by the constant current source 3-2 to be a sinusoidal frequency sweep signal with a constant amplitude, and the voltage signal U _in at both ends of the resistor R is used as input, and the detector 1 The voltage signal U _o at both ends is taken as output, and the frequency response function is defined as

In formula (1), E is the voltage across the resistor R, and E=I R is a constant value, Z _CD is the impedance of the detector,

Where: f represents the frequency, R _c is the DC resistance of the geophone, L _c is the equivalent inductance of the geophone, S ₀ is the open circuit sensitivity of the geophone, f ₀ is the natural frequency of the geophone, ζ ₀ is the damping ratio of the geophone, M is the mass of the moving coil of the detector.

Substitute formula (2) into formula (1) to obtain the frequency response function (3), obtain the first zero-crossing point of the phase-frequency curve by the frequency response function (3), and determine the natural frequency f ₀ ;

Among them: H(f) is the frequency response function of the detector, f is the frequency, R is the series resistance value of the circuit where the detector is located, R _c is the DC resistance of the detector, L _c is the equivalent inductance of the detector, S ₀ is The open-circuit sensitivity of the geophone, f ₀ is the natural frequency of the geophone, ζ ₀ is the damping ratio of the geophone, and M is the mass of the moving coil of the geophone;

Step 2: Connect the DC signal I to the circuit composed of the detector 1 and the resistor R in series, and measure the voltage values at both ends of the resistor R and the detector 1, which are expressed as U _in and U _out respectively, to obtain That is, the DC resistance value of detector 1;

Step 3: Take the real part of the frequency response function (3) and ignore the influence of the inductance to obtain formula (4);

When f = f ₀ ,

when hour,

Let a=R·H _re (f ₀ )-R _c (7)

get,

make

get,

First, the values of a and b are obtained from the frequency response function (3), and by Obtain the damping ratio ζ ₀ of the geophone, and then by The sensitivity S ₀ of the detector is obtained, and the dynamic resistance is defined as the impedance value of the detector when f=f ₀ and the influence of the inductance is neglected, Therefore, the dynamic resistance R _d =R·H(f ₀ );

Through the above calculation process, the characteristic parameters of the geophone 1 are obtained: natural frequency f ₀ , DC resistance value R _c , damping ratio ζ ₀ , open circuit sensitivity S ₀ and dynamic resistance R _d .

Claims (3)

1. the method that geophone characterisitic parameter tester carries out geophone characteristic parameter testing, described geophone characteristic Parameter tester includes temperature sensor (2), signal plate (3) and computer (4), and signal plate is provided with, in (3), the letter being connected Number capture card (3-1) and constant-current source (3-2), temperature sensor (2) is attached on wave detector (1), the output end of wave detector (1) and The output end of temperature sensor (2) is connected with the input of data acquisition card (3-1), the output end of data acquisition card (3-1) It is connected with the input of computer (4), the output end of computer (4) is connected with the input of data acquisition card (3-1), letter The output end of number capture card (3-1) is connected with the input of constant-current source (3-2), the output end of constant-current source (3-2) and wave detector (1) input is connected；

It is characterized in that：The method of described geophone characteristic parameter testing is as follows：

Described computer (4) exports sine sweep signal to data acquisition card (3-1), and data acquisition card (3-1) is by collect This sine sweep signal is converted to the sine of constant amplitude to constant-current source (3-2), constant-current source (3-2) by sine sweep signal output Frequency sweep constant current signal, and by the sine sweep constant current signal output of this constant amplitude to wave detector (1), wave detector (1) rings Answer sine sweep signal and output signal to data acquisition card (3-1), temperature sensor (2) is by the wave detector collecting simultaneously (1) temperature signal exports to data acquisition card (3-1), and data acquisition card (3-1) exports this two paths of signals to computer (4), computer (4) is by being calculated geophone characteristic parameter；Circular is as follows：

Step 1：Obtain first zero crossing of phase frequency curve by frequency response function (3), determine intrinsic frequency f₀；

$H\left(f\right)=\frac{1}{R}\{R_c+\frac{2{\mathrm{\ζ}}_0{f}^2{f}_0{S}_0^2}{2\mathrm{\π}M\[{(f_0^2-f^2)}^2+{\left(2{\mathrm{\ζ}}_0{f}_{0}f\right)}^2\]}+j2{\mathrm{\πfL}}_c+j\frac{S_0^2(f_0^2-f^2)f}{2\mathrm{\π}M\[{(f_0^2-f^2)}^2+{\left(2{\mathrm{\ζ}}_0{f}_{0}f\right)}^2\]}\}---\left(3\right)$

Wherein：H (f) is the frequency response function of wave detector, and f is frequency, and R is the series impedance of wave detector place circuit, R_cFor The D.C. resistance of wave detector, L_cFor wave detector equivalent inductance, S₀For wave detector open circuit sensitivity, f₀For wave detector intrinsic frequency, ζ₀ For the damping ratio of wave detector, M is the moving-coil quality of wave detector；

Step 2：The circuit being composed in series to wave detector (1) and resistance R is passed through direct current signal I, by measuring resistance R and wave detector (1) magnitude of voltage at two ends, is expressed as U_inAnd U_out, obtainThe i.e. D.C. resistance of wave detector (1) Value；

Step 3：Take the real part of frequency response function (3), and ignore the impact of inductance, obtain formula (4)；

$H_{re}\left(f\right)=\frac{1}{R}\[R_c+\frac{2{\mathrm{\ζ}}_0{f}^2{f}_0{S}_0^2}{2\mathrm{\π}M\[{(f_0^2-f^2)}^2+{\left(2{\mathrm{\ζ}}_0{f}_{0}f\right)}^2\]}\]---\left(4\right)$

Work as f=f₀When,

WhenWhen,

Make a=R H_re(f₀)-R_c(7)

Obtain,

Order

Obtain,

First a, b value is obtained by frequency response function (3), byObtain the dampingratioζ of wave detector₀, then byObtain the sensitivity S of wave detector₀, dynamic electric resistor is defined as working as f=f₀And detection when ignoring the impact of inductance The resistance value of device,Therefore dynamic electric resistor R_d=R H (f₀)；

Obtain the characterisitic parameter of wave detector (1) by above-mentioned calculating process：Intrinsic frequency f₀, DC resistance R_c, damping ratio ζ₀, open circuit sensitivity S₀With dynamic electric resistor R_d.

2. method according to claim 1 it is characterised in that：Described temperature sensor (2) adopts PP1000 thermal resistance temperature Degree sensor.

3. method according to claim 1 it is characterised in that：Described data acquisition card (3-1) adopts American National instrument The M series data capture card of NI company.