CN102889076A - Method for calibrating gyro inclinometer - Google Patents

Abstract

The invention relates to a method for calibrating a gyro inclinometer. The method comprises the following steps of: 1) arranging an inclinometry strapdown system on a three-axis turntable, wherein the inclinometry strapdown system transmits data to a computer connected with the inclinometry strapdown system through a data acquisition system and comprises a double-axis dynamic adjustment gyro and three accelerometers; the computer stores sampled measurement data; six groups of measurement data are sampled by the computer; and each group of data comprise a voltage value of an x axis of the gyro, a voltage value of a y axis of the gyro, a voltage value of an x-directional accelerometer, a voltage value of a y-directional accelerometer, a voltage value of a z-directional accelerometer and a voltage value of a temperature sensor; 2) finding out the north direction of the inclinometry strapdown system; and 3) calibrating the inclinometry strapdown system according to crossed position inclinometry. The method for calibrating the gyro inclinometer is suitable for different underground temperature changes, is high in measurement precision and short in measurement time and is applied to an inclinometry strapdown device with the double-axis dynamic adjustment gyro and the three accelerometers.

Description

The gyrolevel scaling method

Technical field

The invention belongs to the petroleum exploration instrument field, relate to a kind of gyrolevel scaling method, relate in particular to the moving scaling method of transferring gyro and three accelerometer strapdown inclination measurement devices of a kind of twin shaft.

Background technology

Gyrolevel is mainly used in measuring well track, for the well assessment provides scientific basis, its core component is inertial measurement cluster, comprises moving gyro and three quartz accelerometers transferred of a twin shaft, adopts the layout of strapdown machinery that the coasting body of precision positioning is arranged in the design.

It is a kind of high accuracy that double-shaft power is coordinated gyro, small size, highly reliable gyroscope.Because of its small volume, so the moving inclinometer of transferring gyro to form with the accelerometer strapdown has been widely used in the well logging.Yet there is multiple error in the moving gyro of transferring in actual measurement, wherein mainly contain by error moment cause zero partially, the error that the scale factor error that fuel factor causes, scale factory non-linearity cause.To with this Sensitive Apparatus of gyro, the variation of the extraneous factors such as acceleration, vibrations, stray magnetic field and temperature all can cause measure error.Therefore design the rational inclinometer scaling method of a cover, set up the perfect gyro error compensation Mathematical Modeling of a cover, just can significantly improve the certainty of measurement of gyrolevel.

At present, the common method of demarcation gyrolevel error model coefficient of deviation has two kinds: 1, traditional eight position measuring method; 2,24 position calibration methods.Two kinds of above-mentioned methods have the problem of some: although the eight position measuring simple and fast is demarcated the weak point that expends time in, the single order that marks zero parital coefficient is not accurate enough, can't satisfy the requirement of high accuracy deviation survey equipment; 24 position calibration methods are compared with traditional eight position measuring method, although on the model parameter stated accuracy raising has been arranged, because the position is too much, the spy will expend too many time and human cost when adding the gyro temperature drift compensation.

Summary of the invention

In order to solve the above-mentioned technical problem that exists in the background technology, the invention provides a kind of gyrolevel scaling method that is used for a twin shaft moving accent gyro and three accelerometer strapdown inclination measurement devices that is applicable to down-hole different temperatures variation, certainty of measurement is high and measures weak point consuming time.

Technical solution of the present invention is: the invention provides a kind of gyrolevel scaling method, its special character is: described gyrolevel scaling method may further comprise the steps:

1) the deviational survey strapdown system is installed on the three-axle table, the deviational survey strapdown system is passed to data in the computer that links to each other with the deviational survey strapdown system by data collecting system; Described deviational survey strapdown system comprises moving gyro and three accelerometers transferred of a twin shaft; The survey data of described computer sampling is kept in the computer; Described at every turn have six groups by the survey data of computer sampling, and every group of data comprise: gyro x shaft voltage value, and gyro y shaft voltage value, x is to the accelerometer magnitude of voltage, and y is to the accelerometer magnitude of voltage, and z is to the accelerometer magnitude of voltage, the temperature pick up magnitude of voltage;

2) find out the direct north of deviational survey strapdown system;

3) according to the X position deviational survey deviational survey strapdown system is demarcated;

The direction indication of each position is as follows in the described X position deviational survey:

Primary importance: gyro x axle energized south, gyro y axle points to the west, and axial acceleration meter direction refers to ground;

The second place: gyro x axle points to east, gyro y axle energized south, and axial acceleration meter direction refers to ground;

The 3rd position: gyro x axle energized south, gyro y axle points to east, and axial acceleration meter direction refers to the sky;

The 4th position: gyro x axle energized south, gyro y axle points to the west, and axial acceleration meter direction refers to ground;

The 5th position: gyro x axle points to the sky, and gyro y axle points to west, axial acceleration meter direction guide;

The 6th position: gyro x axle points to ground, gyro y axle energized north, and axial acceleration meter direction refers to east;

The 7th position: gyro x axle energized north, gyro y axle points to the sky, and axial acceleration meter direction refers to east;

8 positions: gyro x axle energized north, gyro y axle points to ground, and axial acceleration meter direction refers to the west;

The 9th position: gyro x axle energized south, gyro y axle points to the sky, and axial acceleration meter direction refers to the west;

X position: gyro x axle points to east, and gyro y axle points to ground, and axial acceleration meter direction refers to north.

Above-mentioned steps 2) specific implementation is:

2.1) adjust three-axle table, so that hole angle and azimuth are zero, and zero-bit is also adjusted in the tool face azimuth;

2.2) every certain angle rotation first power parallactic angle, will by the gyro voltage data of computer sampling be preserved at every turn, and calculate the median of every group of data;

2.3) with step 2.2) and in the median of the gyro voltage data processed carry out high order fitting, find out the maximum of points on the curve after the match, minimum point, the azimuth size corresponding with maximum of points and big or small with azimuth corresponding to minimum point; The corresponding azimuth of described maximum of points is gyro x sensitive axes, and described azimuth is gyro x axle and positive northern angle;

2.4) according to step 2.3) and in the azimuth size that obtains tool-face is carried out accommodation, obtain finding the direct north of deviational survey strapdown system.

Above-mentioned steps 3) specific implementation is:

3.1) according to the sequencing of X position, on three-axle table, the deviational survey strapdown system put successively ten kinds of attitudes, and adopt respectively the deviational survey strapdown system in the data of diverse location by computer;

3.2) with step 3.1) survey data of sampling is through after the Mathematical treatment, brings the gyrolevel static mathematical model into, with least square method resolve draw in the gyro static models zero parital coefficient and with the proportional coefficient of deviation of acceleration;

3.3) draw when diverse location based on resulting zero parital coefficient of gyrolevel static mathematical model and with the two-dimensional data table of the proportional coefficient of deviation parameter of acceleration, the data of each parameter are carried out curve fitting.

Above-mentioned gyrolevel static mathematical model G is:

${\widetilde{\mathrm{\ω}}}_x={\mathrm{\ω}}_x+B_{\mathrm{fx}}+a_x*B_{\mathrm{xx}}+a_y*B_{\mathrm{xy}}+a_z*B_{\mathrm{xz}}$

${\widetilde{\mathrm{\ω}}}_y={\mathrm{\ω}}_y+B_{\mathrm{fy}}+a_x*B_{\mathrm{yx}}+a_y*B_{\mathrm{yy}}+a_z*B_{\mathrm{yz}}$

${\widetilde{\mathrm{\ω}}}_x=K_x*V_x$

${\widetilde{\mathrm{\ω}}}_y=K_y*V_y$

In the formula:

---the angular velocity measurement value that dynamic tuned gyroscope is measured;

K _x, K _y---be respectively the constant multiplier of gyro x axle and y axle;

V _x, V _y---be respectively the true measurement of gyro x axle and y axle;

ω _x, ω _y---gyro is around the speed of rotation of its power shaft;

a _x, a _y, a _z---respectively along the acceleration of x, y, z direction;

B _Fx, B _Fy---to insensitive zero parital coefficient of acceleration;

B _Xx, B _Xy, B _Xz, B _Yx, B _Yy, B _Yz---with the proportional coefficient of deviation of acceleration.

Above-mentioned gyrolevel scaling method also comprises:

4) environment heats up to external world, and under the different temperatures section deviational survey strapdown system is demarcated.

Above-mentioned steps 4) specific implementation is:

4.1) to external world environment heat up and draw under the different temperature points when diverse location based on resulting zero parital coefficient of gyrolevel static mathematical model and with the two-dimensional data table of the proportional coefficient of deviation parameter of acceleration;

4.2) each coefficient is carried out curve fitting in the data under the different temperatures.

Advantage of the present invention is:

The present invention is after the orthogonality characteristics of having analyzed 24 positions, two positions have newly been added, form a kind of brand-new X position scaling method, whether the height of this X position scaling method precision depends on gyro x axle and overlaps fully with direct north, therefore before carrying out the X position demarcation, at first to find the moving sensitive axes direction of transferring gyro of twin shaft, namely find out the moving angle of transferring gyro x axle and direct north of twin shaft, make gyro x axle consistent with direct north.Adjust respectively the attitude of three-axle table according to X position, preserve the data value of rear each position of sampling.The average of each position is brought among the gyrolevel static mathematical model G, and the at last parsing by least square method obtains needed coefficient of deviation; Simultaneously, consider the temperature conditions of down-hole complexity, gyrolevel has also been carried out the high temperature X position demarcated, make instrument under different temperature conditions, higher certainty of measurement can both be arranged.The present invention has overcome the not high problem of model parameter precision that traditional eight place value standardizations are obtained, oversize problem consuming time when also having solved 24 location position gyro simultaneously.

Description of drawings

Fig. 1 is gyrolevel strapdown mechanism principle figure provided by the present invention;

Fig. 2 is that the gyro that X position provided by the present invention is demarcated points to orientation diagram.

The specific embodiment

The present invention before use, at first the deviational survey strapdown system is installed on the three-axle table, inclinometer is passed to data in the computer that is attached thereto by data collecting system, find out first gyro sensitive axes direction, two positions of new adding on the basis of traditional 8 positions, consist of the X position tilt measurement, and under the different temperatures section to its method of demarcating.

The strapdown mechanism principle that gyro and accelerometer form is installed in inclinometer on the three-axle table referring to Fig. 1, links to each other with data collecting system, and data collecting system is connected on the computer.By sampling, the survey data of each position is kept in the computer with the form of .txt.Data one have six groups in each .txt file, are respectively: gyro x shaft voltage value, and gyro y shaft voltage value, x is to the accelerometer magnitude of voltage, and y is to the accelerometer magnitude of voltage, and z is to the accelerometer magnitude of voltage, the temperature pick up magnitude of voltage.

Because whether the height of X position scaling method precision depends on gyro x axle and overlaps fully with direct north, therefore before carrying out the X position demarcation, at first to find the moving sensitive axes direction of transferring gyro of twin shaft, namely find out the moving angle of transferring gyro x axle and direct north of twin shaft.Calculate by median, the mathematical methods such as curve can be found out this angle, and can calculate constant multiplier Kx, the Ky of gyro sensitive axes.Along gyro axial-rotation inclinometer, make gyro x axle consistent with direct north.At this moment, gyro x axle points to direct north, carries out X position take this position as benchmark and demarcates.

On the basis of above-mentioned work, respectively according to traditional 8 positions, X position is adjusted the attitude of three-axle table, preserves the data value of rear each position of sampling.The average of each position is brought among the gyrolevel static mathematical model G, and the at last parsing by least square method obtains needed coefficient of deviation.

In the present invention, the moving constant multiplier of the sensitive axes of gyro of transferring of twin shaft is:

In the formula:

---the testing location latitude.

V _Max---the maximum value that the gyro sensitive axes records.

V _Min---the minimum value that the gyro sensitive axes records.

In the present invention, gyrolevel static mathematical model G is:

${\widetilde{\mathrm{\ω}}}_x={\mathrm{\ω}}_x+B_{\mathrm{fx}}+a_x*B_{\mathrm{xx}}+a_y*B_{\mathrm{xy}}+a_z*B_{\mathrm{xz}}$

${\widetilde{\mathrm{\ω}}}_y={\mathrm{\ω}}_y+B_{\mathrm{fy}}+a_x*B_{\mathrm{yx}}+a_y*B_{\mathrm{yy}}+a_z*B_{\mathrm{yz}}$

${\widetilde{\mathrm{\ω}}}_x=K_x*V_x$

${\widetilde{\mathrm{\ω}}}_y=K_y*V_y$

In the formula: ---the angular velocity measurement value that dynamic tuned gyroscope is measured;

K _x, K _y---be respectively the constant multiplier of gyro x axle and y axle;

V _x, V _y---be respectively the true measurement of gyro x axle and y axle;

ω _x, ω _y---gyro is around the speed of rotation of its power shaft;

a _x, a _y, a _z---respectively along the acceleration of x, y, z direction;

B _Fx, B _Fy---to insensitive zero parital coefficient of acceleration;

B _Xx, B _Xy, B _Xz, B _Yx, B _Yy, B _Yz---with the proportional coefficient of deviation of acceleration;

Among the present invention, the X position test refers to increase by two positions on original 8 positions basis, consists of new X position method of testing, and particular location is referring to Fig. 2.

The direction indication of each position is as follows:

Primary importance: gyro x axle energized south, gyro y axle points to the west, and axial acceleration meter direction refers to ground.

The second place: gyro x axle points to east, gyro y axle energized south, and axial acceleration meter direction refers to ground.

The 3rd position: gyro x axle energized south, gyro y axle points to east, and axial acceleration meter direction refers to the sky.

The 4th position: gyro x axle energized south, gyro y axle points to the west, and axial acceleration meter direction refers to ground.

The 5th position: gyro x axle points to the sky, and gyro y axle points to west, axial acceleration meter direction guide.

The 6th position: gyro x axle points to ground, gyro y axle energized north, and axial acceleration meter direction refers to east.

The 7th position: gyro x axle energized north, gyro y axle points to the sky, and axial acceleration meter direction refers to east.

8 positions: gyro x axle energized north, gyro y axle points to ground, and axial acceleration meter direction refers to the west.

The 9th position: gyro x axle energized south, gyro y axle points to the sky, and axial acceleration meter direction refers to the west.

X position: gyro x axle points to east, and gyro y axle points to ground, and axial acceleration meter direction refers to north.

The present invention is described in further detail below in conjunction with accompanying drawing and example:

The concrete calibration process of twin shaft dynamical tuned gyroscopes inclinometer is as follows:

Step 1: the measurement of gyro x axle and positive northern angle

1) adjusts three-axle table, so that hole angle and azimuth are zero, and also adjust to zero-bit with the tool face azimuth, be beneficial to like this and draw gyro x axle and positive northern angle.

2) every 10 ° of rotation first power parallactic angles, each sampled data is preserved into the .txt file, and obtain the median of every group of data in the .txt file, test altogether 36 times, so just can obtain 36 groups of data.

3) with step 2) in the gyro voltage data of trying to achieve carry out high order fitting, concrete exponent number can decide according to actual conditions.Find out the maximum of points on the curve and minimum point after the match and corresponding azimuth size with it.

4) azimuth corresponding to maximum of points is gyro x sensitive axes, and this azimuth is exactly gyro x axle and the positive northern angle that requires in the step 1).

5) adjust accordingly tool-face according to the corner dimension of obtaining in the step 4), just find the gyrolevel direct north this moment.Can carry out the demarcation of X position on this basis.

Step 2: the demarcation of X position under the different temperatures section

1) according to the order of table 1, on three-axle table, inclinometer put successively ten kinds of attitudes, and record respectively its value.

In the table 1: Ω---rotational-angular velocity of the earth;

Φ---local latitude;

2) ask median to process the data of the gyro x axle of 1 extraction and y axle and three accelerometers after, bring the gyrolevel static mathematical model into, with least square method resolve draw in the model with the irrelevant zero parital coefficient of acceleration and with the proportional coefficient of deviation of acceleration.

3) certain variation can occur in the static models parameter of the different gyros of temperature, can adapt to the hot environment of down-hole harshness in order to make model, need to carry out the high temperature compensation to gyrolevel.With the residing environment temperature of gyrolevel be heated to 35 the degree, according to step 1) and step 2) in method it is demarcated and calculates.

4) the every rising of external environment 15 degree are all according to step 1) and step 2) in method gyrolevel is demarcated and is calculated.Consider the at present moving gyro hot properties of transferring, the highest 95 degree that are set as of its probe temperature.

5) through after above-mentioned 4 steps, draw the two-dimensional data table of each model parameter under the different temperature points, each coefficient is carried out curve fitting in the data under the different temperatures.

Below the present invention is described in detail as example take a specific embodiment:

1, gyrolevel is installed on the three-axle table in the baking oven, connects computer and sample devices, whether checkout facility is working properly.Carry out gyrolevel according to step 1 in the concrete calibration process of gyrolevel and seek north work.

2, adjust turntable according to the different attitudes of table 1 X position, preserve the value of the accelerometer on the value of gyro x axle, y axle under each attitude and x, y, three directions of z.

3, the testing location latitude is 39 ° 45 ', and 25 ° of C of probe temperature according to the rotational-angular velocity of the earth component formula in the gyrolevel calibration process step 1, calculate the axial rotational-angular velocity of the earth component value of gyro x axle, y under the X position.By the parsing of least square method, draw in the gyro static models with accelerometer irrelevant zero partially value and with the proportional drift value of accelerometer.

4, carry out High temperature calibration according to 4.5 pairs of instruments in the step 2, adjust oven temperature, 15 ° of C of the every rising of temperature carry out an X position demarcation and data are carried out Least Square in Processing.Can draw the two-dimensional data table of each model parameter under the different temperature points, such as table 2.The temperature section of dividing is less, and the data that simulate are just more near actual value, but corresponding test job amount is just larger, needs each factor balance to consider.Through High temperature calibration, therefore when gyrolevel is operated in arbitrary temperature, can find corresponding parameter value at curve.

Table 1

Table 2

Temperature	Bxx	Bxy	Byx	Byy
					35	-15.0633	-0.1472138	-0.492065	-16.25977
50	-12.6415	-0.2229552	-0.391369	-14.03922
					65	-10.8504	-0.2433	-0.838454	-11.40377
80	-7.09499	0.22825786	-1.203706	-7.866209
					95	-4.0268	0.6329	-1.482934	-4.653914

Claims (6)

1. gyrolevel scaling method, it is characterized in that: described gyrolevel scaling method may further comprise the steps:

1) the deviational survey strapdown system is installed on the three-axle table, the deviational survey strapdown system is passed to data in the computer that links to each other with the deviational survey strapdown system by data collecting system; Described deviational survey strapdown system comprises moving gyro and three accelerometers transferred of a twin shaft; The survey data of described computer sampling is kept in the computer; Described at every turn have six groups by the survey data of computer sampling, and every group of data comprise: gyro x shaft voltage value, and gyro y shaft voltage value, x is to the accelerometer magnitude of voltage, and y is to the accelerometer magnitude of voltage, and z is to the accelerometer magnitude of voltage, the temperature pick up magnitude of voltage;

2) find out the direct north of deviational survey strapdown system;

3) according to the X position deviational survey deviational survey strapdown system is demarcated;

The direction indication of each position is as follows in the described X position deviational survey:

Primary importance: gyro x axle energized south, gyro y axle points to the west, and axial acceleration meter direction refers to ground;

The second place: gyro x axle points to east, gyro y axle energized south, and axial acceleration meter direction refers to ground;

The 3rd position: gyro x axle energized south, gyro y axle points to east, and axial acceleration meter direction refers to the sky;

The 4th position: gyro x axle energized south, gyro y axle points to the west, and axial acceleration meter direction refers to ground;

The 5th position: gyro x axle points to the sky, and gyro y axle points to west, axial acceleration meter direction guide;

The 6th position: gyro x axle points to ground, gyro y axle energized north, and axial acceleration meter direction refers to east;

The 7th position: gyro x axle energized north, gyro y axle points to the sky, and axial acceleration meter direction refers to east;

8 positions: gyro x axle energized north, gyro y axle points to ground, and axial acceleration meter direction refers to the west;

The 9th position: gyro x axle energized south, gyro y axle points to the sky, and axial acceleration meter direction refers to the west;

X position: gyro x axle points to east, and gyro y axle points to ground, and axial acceleration meter direction refers to north.

2. gyrolevel scaling method according to claim 1, it is characterized in that: specific implementation described step 2) is:

2.1) adjust three-axle table, so that hole angle and azimuth are zero, and zero-bit is also adjusted in the tool face azimuth;

2.2) every certain angle rotation first power parallactic angle, will by the gyro voltage data of computer sampling be preserved at every turn, and calculate the median of every group of data;

2.3) with step 2.2) and in the median of the gyro voltage data processed carry out high order fitting, find out the maximum of points on the curve after the match, minimum point, the azimuth size corresponding with maximum of points and big or small with azimuth corresponding to minimum point; The corresponding azimuth of described maximum of points is gyro x sensitive axes, and described azimuth is gyro x axle and positive northern angle;

2.4) according to step 2.3) and in the azimuth size that obtains tool-face is carried out accommodation, obtain finding the direct north of deviational survey strapdown system.

3. gyrolevel scaling method according to claim 2, it is characterized in that: the specific implementation of described step 3) is:

3.1) according to the sequencing of X position, on three-axle table, the deviational survey strapdown system put successively ten kinds of attitudes, and adopt respectively the deviational survey strapdown system in the data of diverse location by computer;

3.2) with step 3.1) survey data of sampling is through after the Mathematical treatment, brings the gyrolevel static mathematical model into, with least square method resolve draw in the gyro static models zero parital coefficient and with the proportional coefficient of deviation of acceleration;

3.3) draw when diverse location based on resulting zero parital coefficient of gyrolevel static mathematical model and with the two-dimensional data table of the proportional coefficient of deviation parameter of acceleration, the data of each parameter are carried out curve fitting.

4. gyrolevel scaling method according to claim 3, it is characterized in that: described gyrolevel static mathematical model G is:

${\widetilde{\mathrm{\ω}}}_x={\mathrm{\ω}}_x+B_{\mathrm{fx}}+a_x*B_{\mathrm{xx}}+a_y*B_{\mathrm{xy}}+a_z*B_{\mathrm{xz}}$

${\widetilde{\mathrm{\ω}}}_y={\mathrm{\ω}}_y+B_{\mathrm{fy}}+a_x*B_{\mathrm{yx}}+a_y*B_{\mathrm{yy}}+a_z*B_{\mathrm{yz}}$

${\widetilde{\mathrm{\ω}}}_x=K_x*V_x$

${\widetilde{\mathrm{\ω}}}_y=K_y*V_y$

In the formula:

---the angular velocity measurement value that dynamic tuned gyroscope is measured;

K _x, K _y---be respectively the constant multiplier of gyro x axle and y axle;

V _x, V _y---be respectively the true measurement of gyro x axle and y axle;

ω _x, ω _y---gyro is around the speed of rotation of its power shaft;

a _x, a _y, a _z---respectively along the acceleration of x, y, z direction;

B _Fx, B _Fy---to insensitive zero parital coefficient of acceleration;

B _Xx, B _Xy, B _Xz, B _Yx, B _Yy, B _Yz---with the proportional coefficient of deviation of acceleration.

5. gyrolevel scaling method according to claim 4, it is characterized in that: described gyrolevel scaling method also comprises:

4) environment heats up to external world, and under the different temperatures section deviational survey strapdown system is demarcated.

6. gyrolevel scaling method according to claim 5, it is characterized in that: the specific implementation of described step 4) is:

4.1) to external world environment heat up and draw under the different temperature points when diverse location based on resulting zero parital coefficient of gyrolevel static mathematical model and with the two-dimensional data table of the proportional coefficient of deviation parameter of acceleration;

4.2) each coefficient is carried out curve fitting in the data under the different temperatures.

Images