CN109870153B - Magnetometer orthogonality calibration test method and calibration test device - Google Patents

Abstract

The invention provides a magnetometer orthogonality calibration test method and a calibration test device, wherein the method comprises the steps of placing a magnetometer in calibration equipment, wherein the magnetometer is positioned in a uniform area of an alternating current magnetic field of the calibration equipment; rotating the magnetometer in the alternating magnetic field, the magnetometer rotating in the alternating magnetic field in a plurality of different orientations; and recording the output data of the alternating current magnetic field detected by the magnetometer in each azimuth within recording time, and performing calibration test on the alternating current orthogonality of the magnetometer by adopting the magnetic field modulus of the alternating current magnetic field given by the coil. The method and the device can calibrate the alternating current orthogonality of the magnetometer and fill the blank of the magnetometer, particularly the three-axis magnetometer in the field of alternating current calibration testing. The invention has accurate calibration test result for the calibration test of the alternating current orthogonality of the magnetometer. The calibration test device is simple to operate and convenient to calculate, and can complete calibration of all error items.

Description

A magnetometer orthogonality calibration test method and calibration test device

technical field

The invention relates to the field of calibration of a three-axis magnetometer, in particular to a calibration test method and calibration test device for the orthogonality of a magnetometer.

Background technique

Due to the manufacturing error and assembly error of the three-axis magnetometer, as well as the interference of the external ferromagnetic object to the magnetic field, the accuracy of the measurement of the geomagnetic field is low. The error of the magnetometer comes from the environmental interference and the error of the magnetometer itself. Environmental interference includes hard magnetic interference and soft magnetic interference. The main errors of the magnetometer itself include zero bias error, scale factor error, non-orthogonal error, and installation alignment error. These errors seriously affect the accuracy of the magnetometer used in heading determination and attitude measurement. It needs to be calibrated to obtain the error coefficient and then compensate the original output of the magnetometer.

At present, there are many calibration methods, mainly including:

1. The magnetometer rotates once in the horizontal plane, and the maximum and minimum output values of the magnetometer are used to complete the calibration of the scale factor error and zero bias error of the 2-axis magnetometer. However, this method can only complete the 2-axis magnetometer calibration, and can only calibrate part of the error terms, and the accuracy is low.

2. Through the ellipsoid fitting calibration method of the rotating magnetometer in three-dimensional space, it cannot calibrate the rotation error term caused by soft magnetic interference, non-orthogonal error, and installation error, and the compensation effect is limited. The ball fitting process is computationally expensive.

3. Use a high-precision non-magnetic turntable to determine the direction, and obtain the magnetic field data through a higher-precision magnetometer, and determine the error coefficient through experiments. The correction accuracy is high, but the equipment requirements are high and the operation is complicated.

4. Fix the magnetometer in the cube, and solve the error coefficient of the magnetometer through 12 different placement orientations. However, this method has high requirements on the accuracy of the 12 orientations, and relies on fewer data points. When the random noise is large, it is easy to generate a large calibration error.

In general, the current related calibration methods have disadvantages such as high equipment requirements, complicated operations, complicated calculations, only complete calibration of some error terms, or only suitable for calibration of 2-axis magnetometers.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies and defects of the magnetometer, especially the three-axis magnetometer calibration method in the prior art, the present invention provides a magnetometer AC orthogonality calibration test method and calibration test device.

According to an embodiment of the present invention, a magnetometer AC orthogonality calibration test method is provided, including:

The magnetometer is placed in the calibration device, the magnetometer is located in a uniform area of the AC magnetic field of the calibration device, and the relationship between the total magnetic field strength B at any point in the AC magnetic field and the ^three magnetic field components As shown in equation (1):

The magnetometer is rotated in the AC magnetic field, the magnetometer is rotated in a plurality of different orientations in the AC magnetic field, and the three magnetic field components of the AC magnetic field are measured in each orientation respectively. The non-orthogonality of the three axes of the magnetometer, the measured values B' _x , B' _y , and B' _z of the three magnetic field components of the alternating magnetic field are respectively shown in equations (2)-(3):

B' _x =S _x +B _x +x ₀ (2),

B' _y =S _y (B _y cos(ρ)+B _x sin(ρ))+y ₀ (3),

根据所述磁强计测得的所述交流磁场的所述三个磁场分量B'_x、B'_y、B'_z的多组测量值，获得系数S_x、S_y、S_z、x₀、y₀、z₀、ρ、

及λ；

Coefficients S _x , S _y , S _z , x ₀ are obtained according to multiple sets of measurement values of the three magnetic field components B' _x , B' _y , B' _z of the alternating magnetic field measured by the magnetometer , y ₀ , z ₀ , ρ,

and λ;

The output data of the AC magnetic field detected by the magnetometer in each of the azimuths are recorded during the recording time, and the AC quadrature of the magnetometer is applied to the magnetic field modulus of the AC magnetic field given by the coil. performance calibration test;

where S _x , S _y , S _z are the scale factor errors of the three magnetic field components of the magnetic field;

x ₀ , y ₀ , z ₀ are the zero points of the alternating magnetic field;

表示测量值B'_z在z方向上的偏离角；λ表示测量值B_z在x方向上的偏离角。ρ represents the deviation angle of the measured value B'y in the _y direction;

represents the deviation angle of the measured value _{B'z in the z direction; λ represents the deviation angle of the measurement value B z in} the x direction.

及λ还包括如下步骤：Optionally, according to the equations (2)-(4), the coefficients S _x , S _y , S _z , x ₀ , y ₀ , z ₀ , ρ,

and λ also includes the following steps:

_Combine the equations (2)-(4) to obtain B _x , By , and B _z , and substitute into the equation (1) to obtain the following equation (5):

及λ的函数，通过多组所述测量值B'_x、B'_y、B'_z，采用最小二乘法拟合出所述系数A1、B1、C1、D1、E1、F1、G1、H1、I1及J1。Among them, coefficients A1, B1, C1, D1, E1, F1, G1, H1, I1 and J1 are S _x , S _y , S _z , x ₀ , y ₀ , z ₀ , ρ,

and the function of _λ , the coefficients _A1 , _B1 , C1, D1, E1, F1, G1, H1, I1 and J1.

Optionally, the amplitude of the alternating current magnetic field ranges from 0 nT to 100,000 nT, and the frequency ranges from 0.0001 Hz to 100 kHz.

Optionally, the magnetometer rotates in at least 9 different directions in the alternating magnetic field, and the recording time is not less than 1 min.

Optionally, after the magnetometer is placed in the calibration device, the step of preheating the magnetometer is further included, wherein the preheating time of the magnetometer is not less than 15 minutes.

Optionally, the output data of the AC magnetic field includes a peak-to-peak value of the magnetic field or a power spectrum value.

Optionally, the calibration device includes a three-axis magnetic field coil, a magnetic field interference elimination system and a three-way constant current power supply, and the magnetic field interference elimination system includes a three-axis compensation coil, an optical pump magnetometer, and an interference magnetic field compensation control system,

After the magnetometer is placed in the calibration device, a current is applied to the three-axis magnetic field coil to form the alternating magnetic field, and the magnetic field interference cancellation system works to eliminate the interference of the environmental magnetic field on the magnetic field.

Optionally, before placing the magnetometer on the calibration device, it also includes fixing the magnetometer on a non-magnetic three-axis turntable, and the non-magnetic three-axis turntable is placed on the three-axis magnetic field. in the coil.

Optionally, the non-magnetic three-axis turntable includes:

Horizontally set turntable α;

Above the turntable α, the turntable γ also arranged horizontally; and

a turntable β arranged perpendicular to the turntable α and the turntable γ;

The turntable α and the turntable γ are arranged parallel to each other and spaced apart, the turntable β includes at least a pair of oppositely arranged turntables, the center of the turntable β is set outside the edge of the turntable γ, and the turntable β The turntable γ is supported, and the edge of the turntable α is connected with the edge of the turntable β to support the turntable β.

Optionally, the non-magnetic three-axis turntable further includes a support frame, the support frame includes a support surface and a support column for fixing and supporting the support surface, and the turntable α is rotatably arranged on the support frame. on the support surface.

Optionally, the magnetometer is fixed at the center of the turntable γ, and the center of the magnetometer coincides with the center of the turntable γ and rotates with the rotation of the turntable γ.

According to another embodiment of the present invention, a magnetometer AC orthogonality calibration test device is provided, including:

Calibration equipment for generating alternating magnetic fields;

The non-magnetic three-axis turntable is used to fix the magnetometer, and the non-magnetic three-axis turntable fixed with the magnetometer is placed in the uniform area of the AC magnetic field, and the non-magnetic three-axis turntable drives the magnetic the strength meter rotates in a plurality of different orientations in the alternating magnetic field;

A data processing unit, electrically connected with the magnetometer, is used for receiving the output data of the AC magnetic field detected by the magnetometer in each of the azimuths within the recording time, and performing the output data on the output data. Analytical processing.

Optionally, the amplitude of the AC magnetic field generated by the calibration device ranges from 0 nT to 100,000 nT, and the frequency ranges from 0.0001 Hz to 100 kHz.

Optionally, the calibration device includes that the calibration device includes a three-axis magnetic field coil, a magnetic field interference elimination system, and a three-way constant current power supply,

wherein, applying a current to the three-axis magnetic field coil to form the alternating magnetic field;

The magnetic field interference elimination system includes a three-axis compensation coil, an optical pump magnetometer, and an interference magnetic field compensation control system, and the magnetic field interference elimination system is used to eliminate the interference of the environmental magnetic field on the magnetic field.

Optionally, the non-magnetic three-axis turntable includes:

Horizontally set turntable α;

Above the turntable α, the turntable γ also arranged horizontally; and

a turntable β arranged perpendicular to the turntable α and the turntable γ;

The turntable α and the turntable γ are arranged parallel to each other and spaced apart, the turntable β includes at least a pair of oppositely arranged turntables, the center of the turntable β is set outside the edge of the turntable γ, and the turntable β The turntable γ is supported, and the edge of the turntable α is connected with the edge of the turntable β to support the turntable β.

Optionally, the non-magnetic three-axis turntable further includes a support portion, the support portion includes a support surface and a support column for fixing and supporting the support surface, and the turntable α is rotatably arranged on the support frame. on the support surface.

Optionally, the magnetometer is fixed at the center position of the turntable γ and can rotate with the rotation of the turntable γ.

As mentioned above, the magnetometer AC orthogonality calibration test method and calibration test device of the present invention have the following technical effects:

The method and device of the present application can calibrate and test the AC orthogonality of a magnetometer, which fills the gap in the field of AC calibration and testing of magnetometers, especially three-axis magnetometers. The invention performs the calibration test of the alternating current orthogonality of the magnetometer, and the calibration test result is accurate.

The calibration testing device of the invention is simple in operation and convenient in calculation, and can complete the calibration of all error terms.

Description of drawings

The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are schematic and should not be construed as limiting the invention in any way, in which:

FIG. 1 shows a flow chart of a method for calibrating and testing the orthogonality of a magnetometer according to the first embodiment.

FIG. 2 is a schematic diagram of the apparatus of the calibration apparatus in the method shown in FIG. 1 .

FIG. 3 is a schematic diagram showing the principle of the calibration device in the method shown in FIG. 1 .

FIG. 4 is a schematic diagram of the non-magnetic three-axis turntable in the method shown in FIG. 1 .

FIG. 5 shows a schematic diagram of the included angle between the three axes of the magnetometer and the coordinate axis when the three axes are not orthogonal.

reference number

10 Magnetometer

20 Non-magnetic three-axis turntable

201 Turntable¶

202 Turntable β

203 Turntable Alpha

204 Support surface

205 Support column

30 Calibration equipment

301 three-axis magnetic field coil

302 shield shell

303 accommodating chamber

304 Fixed part

305 Three-axis compensation coil A

306 Three-axis compensation coil B

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

This embodiment provides a magnetometer orthogonality calibration test method, as shown in FIG. 1 , the method includes the following steps:

placing a magnetometer in a calibration device, the magnetometer being located in a uniform region of the AC magnetic field of the calibration device;

In a preferred embodiment of the embodiment, after the magnetometer is placed in the calibration device, a step of preheating the magnetometer may be performed first, for example, the magnetometer may be preheated for at least 15 minutes. After the preheating process, on the one hand, the temperature of the magnetometer itself, such as its probe, tends to balance; on the other hand, the electronic performance of each electronic device in the magnetometer, such as the probe, is It can be stabilized in a process, so that the performance of the whole magnetometer is in a stable state. In this way, calibration errors caused by unstable temperature or magnetometer performance can also be avoided, thereby improving the accuracy of the orthogonality calibration of the magnetometer.

As shown in FIG. 2 , the magnetometer 10 is located in the calibration device 30 , specifically, in the accommodating chamber 303 of the calibration device 30 . In the preferred embodiment of this embodiment, before placing the magnetometer 10 on the calibration device, first fix the magnetometer on the non-magnetic three-axis turntable 20 shown in FIG. 4 , and then attach the non-magnetic three-axis turntable 20 together with the The magnetometer 10 fixed thereon is placed in the accommodating chamber 303 of the calibration device 30 .

In a preferred embodiment of this embodiment, as shown in FIG. 3 , the calibration device 30 includes a magnetic field interference cancellation system and a three-axis magnetic field coil 301 , wherein the magnetic field interference cancellation system includes a first three-axis compensation coil 305 and a third The two-three-axis compensation coil 306 , the optical pump magnetometer and the interference magnetic field compensation control system (not shown) are used to eliminate the interference of the ambient magnetic field on the AC magnetic field generated by the calibration device 30 . The three-axis magnetic field coil 301 of the calibration device 30 is used to generate an AC magnetic field. In a preferred embodiment of this embodiment, the amplitude of the generated AC magnetic field ranges from 0 nT to 100000 nT, and the frequency ranges from 0.0001 Hz to 100 kHz. In a more preferred embodiment, the amplitude of the alternating magnetic field is 50 nT and the frequency is 1 Hz.

At any point in the uniform region of the alternating magnetic field, the relationship between the total magnetic field strength B ² of the magnetic field and the three magnetic field components is shown in equation (1):

In addition, in another preferred embodiment of this embodiment, as shown in FIG. 2 , the calibration device 30 further includes a shielding case 302 , and the shielding case 302 can also play a role in eliminating the interference of the environmental magnetic field. The calibration device 30 further includes a fixing part 304 , and the fixing part 304 keeps the whole calibration device 30 in a stable state without mechanical vibration or movement, so as not to affect the calibration result.

rotating the magnetometer in the alternating magnetic field, the magnetometer rotating in a plurality of different orientations in the alternating magnetic field;

In the preferred embodiment of this embodiment, the magnetometer is rotated in at least 9 different directions. For example, in the preferred embodiment of this embodiment, the magnetometer is fixed on the non-magnetic three-axis turntable 20 . As shown in FIG. 4 , the non-magnetic three-axis turntable 20 includes a turntable α203 arranged horizontally; a turntable γ201 located above the turntable α203 and also arranged horizontally; and a turntable β202 arranged perpendicular to the turntable α203 and the turntable γ201 . In a preferred embodiment of this embodiment, the turntable α203 and the turntable γ201 are arranged parallel to each other and spaced apart. The turntable β202 includes at least a pair of oppositely arranged turntables, such as a pair of oppositely arranged turntables β202 shown in FIG. 3 . And the center of the turntable β202 is set outside the edge of the turntable γ201 , and the turntable β202 supports the turntable γ. The edge of the turntable α is connected with the edge of the turntable β to support the turntable β.

In another preferred embodiment of this embodiment, the magnetometer 10 is fixed at the center of the turntable γ201 , and the center of the magnetometer 10 is arranged to coincide with the center of the turntable γ201 . During the calibration test of the magnetometer 10, a driving force is applied to the non-magnetic three-axis turntable 20, so that the turntable α203, the turntable β202 and the turntable γ20 of the non-magnetic three-axis turntable 20 are rotated, thereby driving the magnets fixed on the turntable γ201. Strong meter 10 turns. Rotate in at least 9 different directions according to the needs of the calibration test. For example, if the turntable α203 is rotated in the horizontal plane, the turntable β202 does not rotate relative to the turntable α203, but is driven by the turntable α203 to rotate in the horizontal plane. The turntable γ201 does not want to rotate the turntable α203 or the turntable β202, but the turntable β202 The rotation of the magnetometer is driven to rotate in the horizontal plane, so that the magnetometer can be rotated to different pitch angles as required. In addition, the turntable α203 is made stationary, and the turntable β202 rotates in the vertical plane relative to the turntable α203, thereby driving the turntable γ201 together with the magnetometer 10 fixed on it to rotate in the vertical plane, thereby rotating the magnetometer at different roll angles. .

In a preferred embodiment of this embodiment, the magnetometer is rotated as shown in Table 1 below:

Table 1 Rotation direction of magnetometer

As shown in Table 1, the magnetometer rotates at least within the hemisphere by several different angles, thereby increasing the output data of the magnetometer and increasing the accuracy of the calibration test.

Record the output data of the AC magnetic field detected by the magnetometer in each of the azimuths within a predetermined time, and use the magnetic field modulus of the AC magnetic field given by the coil to the AC quadrature of the magnetometer In a preferred embodiment of this embodiment, the output data of the AC magnetic field includes the peak-to-peak value of the output magnetic field or the power spectrum value.

表示测量值B'_z在z方向上的偏离角；λ表示测量值B_z在x方向上的偏离角。Due to the non-orthogonality of the three axes of the magnetometer, there is an included angle between the three axes of the magnetometer 10 and the coordinate axis, as shown in FIG. 5 , ρ represents the measured value B′ _y in the y direction deviation angle;

represents the deviation angle of the measured value _{B'z in the z direction; λ represents the deviation angle of the measurement value B z in} the x direction.

The measured values of the three magnetic field components of the AC magnetic field are respectively shown in equations (2)-(3):

B' _x =S _x +B _x +x ₀ (2);

B' _y =S _y (B _y cos(ρ)+B _x sin(ρ))+y ₀ (3);

Combining the equations (2)-(4) yields B _x , _{By , B z .} Substituting into the equation (1) yields the following equation (5):

及λ的函数，通过多组所述测量值B'_x、B'_y、B'_z，采用最小二乘法拟合出所述系数A1、B1、C1、D1、E1、F1、G1、H1、I1及J1。Among them, coefficients A1, B1, C1, D1, E1, F1, G1, H1, I1 and J1 are S _x , S _y , S _z , x ₀ , y ₀ , z ₀ , ρ,

and the function of _λ , the coefficients _A1 , _B1 , C1, D1, E1, F1, G1, H1, I1 and J1.

及λ；Said equations (2)-(4) are then solved to yield coefficients S _x , S _y , S _z , x ₀ , y ₀ , z ₀ , ρ,

and λ;

where S _x , S _y , S _z are the scale factor errors of the three magnetic field components of the magnetic field;

x ₀ , y ₀ , z ₀ are the zero points of the alternating magnetic field.

In a preferred embodiment of this embodiment, the recording time of each azimuth is not less than 1 min, so that the output data of the magnetometer 10 can be recorded more accurately, and the error of the magnetometer calibration test can be reduced.

Embodiment 2

This embodiment provides a magnetometer orthogonality calibration test device, the device includes:

Calibration equipment for generating alternating magnetic fields;

The non-magnetic three-axis turntable is used to fix the magnetometer to be calibrated and tested, and the magnetometer is placed in the uniform area of the AC magnetic field, and the non-magnetic three-axis turntable drives the magnetometer in the Rotate in multiple different directions in the AC magnetic field;

A data processing unit, electrically connected to the magnetometer 10, for receiving the output data of the AC magnetic field detected by the magnetometer in each of the azimuths within the recording time, and for processing the output data Perform analytical processing. For example, the data processing unit may perform the operation described in Embodiment 1 according to the output data of the magnetometer to obtain each coefficient.

As shown in FIG. 3 , the calibration device 30 includes a magnetic field interference cancellation system and a three-axis magnetic field coil 301, wherein the magnetic field interference cancellation system includes a first three-axis compensation coil A 305 and a second three-axis compensation coil B 306, an optical pump magnetic force and an interference magnetic field compensation control system (not shown), the magnetic field interference cancellation system is used to eliminate the interference of the ambient magnetic field on the alternating magnetic field generated by the calibration device. The three-axis magnetic field coil 301 is used to generate an AC magnetic field. In a preferred embodiment of this embodiment, the amplitude of the generated AC magnetic field ranges from 0 nT to 100000 nT, and the frequency ranges from 0.0001 Hz to 100 kHz. In a more preferred embodiment, the amplitude of the alternating magnetic field is 50 nT and the frequency is 1 Hz.

As shown in FIG. 4 , the non-magnetic three-axis turntable 20 includes a turntable α203 arranged horizontally; a turntable γ201 located above the turntable α203 and also arranged horizontally; and a turntable β202 arranged perpendicular to the turntable α203 and the turntable γ201 . In a preferred embodiment of this embodiment, the turntable α203 and the turntable γ201 are arranged parallel to each other and spaced apart. The turntable β202 includes at least a pair of oppositely arranged turntables, such as a pair of oppositely arranged turntables β202 shown in FIG. 3 . And the center of the turntable β202 is set outside the edge of the turntable γ201 , and the turntable β202 supports the turntable γ. The edge of the turntable α is connected with the edge of the turntable β to support the turntable β.

In another preferred embodiment of this embodiment, the magnetometer 10 is fixed at the center of the turntable γ201 , and the center of the magnetometer 10 is arranged to coincide with the center of the turntable γ201 . When performing the calibration test of the magnetometer 10, a driving force is applied to the non-magnetic three-axis turntable 20, so that the non-magnetic three-axis turntable 20 rotates, and the turntable α203, the turntable β202 and the turntable γ20 rotate at the same time, thereby driving the fixed on the turntable γ201. The magnetometer 10 on it rotates. According to the needs of the calibration test, the non-magnetic three-axis turntable 20 can rotate in at least 9 different directions.

In a preferred embodiment of this embodiment, the magnetometer is also rotated as shown in Table 1 in the first embodiment. As shown in Table 1, the magnetometer rotates at least within the hemisphere by several different angles, thereby increasing the output data of the magnetometer and increasing the accuracy of the calibration test.

The magnetometer AC orthogonality calibration test method and calibration test device of the above-mentioned embodiments have the following technical effects:

The method and device of the present application can calibrate and test the AC orthogonality of a magnetometer, which fills the gap in the field of AC calibration and testing of magnetometers, especially three-axis magnetometers. The invention calibrates and tests the AC orthogonality of the magnetometer, and the calibration and test results are accurate.

The calibration testing device of the invention is simple in operation and convenient in calculation, and can complete the calibration of all error terms.

The above-mentioned embodiments are only illustrative of the principles and effects of the present invention, but are not intended to limit the present invention. Those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and modifications are within the scope defined by the appended claims.

Claims (17)

1. A magnetometer alternating current orthogonality calibration test method is characterized by comprising the following steps:

placing the magnetometer in calibration equipment, wherein the magnetometer is positioned in a uniform area of an alternating-current magnetic field of the calibration equipment, and the total magnetic field intensity B of any point in the alternating-current magnetic field²The relationship with the three magnetic field components is shown in equation (1):

rotating the magnetometer in the alternating current magnetic field, the magnetometer rotating a plurality of different orientations in the alternating current magnetic field, measuring three magnetic field components of the alternating current magnetic field in each orientation, respectively, due to the non-orthogonality of the three axes of the magnetometer, the measurement values B 'of the three magnetic field components of the alternating current magnetic field'_x、B'_y、B'_zAs shown in equations (2) - (3), respectively:

B'_x＝S_x+B_x+x₀(2)，

B'_y＝S_y(B_ycos(ρ)+B_xsin(ρ))+y₀(3)，

the three magnetic field components B 'of the AC magnetic field measured by the magnetometer'_x、B'_y、B'_zTo obtain a coefficient S_x、S_y、S_z、x₀、y₀、z₀Rho, phi and lambda;

recording the output data of the alternating current magnetic field detected by the magnetometer in each azimuth within recording time, and performing calibration test on the alternating current orthogonality of the magnetometer by adopting the magnetic field modulus of the alternating current magnetic field given by a coil;

wherein S is_x、S_y、S_zIs a scale factor error of three of said magnetic field components of said magnetic field;

x₀、y₀、z₀is the zero point of the alternating magnetic field;

ρ represents a measured value B'_yOff angle in the y direction; phi denotes measured value B'_zOff angle in the z direction; λ represents the measured value B_zOff angle in the x direction;

the recording time is not less than 1 min.

2. Calibration according to claim 1Test method, characterized in that, according to said equations (2) - (4), a coefficient S is obtained_x、S_y、S_z、x₀、y₀、z₀、ρ、

And λ further comprising the steps of:

combining the equations (2) - (4) to obtain B_x、B_y、B_zSubstituting said equation (1) results in the following equation (5):

wherein the coefficients A1, B1, C1, D1, E1, F1, G1, H1, I1 and J1 are S_x、S_y、S_z、x₀、y₀、z₀、ρ、

And λ, by a plurality of sets of said measured values B'_x、B'_y、B'_zAnd fitting the coefficients A1, B1, C1, D1, E1, F1, G1, H1, I1 and J1 by using a least square method.

3. The calibration test method according to claim 1, wherein the amplitude of the alternating magnetic field is in the range of 0nT to 100000nT, and the frequency is in the range of 0.0001Hz to 100 kHz.

4. The calibration test method of claim 1, wherein said magnetometer is rotated in said alternating magnetic field in at least 9 different said orientations.

5. The calibration test method of claim 1, wherein the output data of the alternating magnetic field comprises magnetic field peak-to-peak values or power spectrum values.

6. The calibration testing method of claim 1, further comprising the step of preheating the magnetometer after the magnetometer is placed in the calibration device, wherein the preheating time of the magnetometer is not less than 15 min.

7. The calibration testing method according to claim 1, wherein the calibration device comprises a three-axis magnetic field coil, a magnetic field interference cancellation system and a three-way constant current power supply, the magnetic field interference cancellation system comprises a three-axis compensation coil, an optical pump magnetometer and an interference magnetic field compensation control system,

after the magnetometer is placed in the calibration equipment, current is applied to the three-axis magnetic field coil to form the alternating-current magnetic field, and meanwhile, the magnetic field interference elimination system works to eliminate the interference of an environmental magnetic field on the magnetic field.

8. The calibration testing method of claim 7, further comprising, prior to placing the magnetometer on the calibration device, securing the magnetometer on a non-magnetic tri-axial turntable placed in the tri-axial magnetic field coil.

9. The calibration testing method of claim 8, wherein the nonmagnetic three-axis turntable comprises:

a horizontally disposed turntable α;

a turntable gamma which is positioned above the turntable α and is also horizontally arranged, and

a turntable β disposed perpendicular to the turntable α and the turntable γ;

wherein the turntable α and the turntable γ are disposed in parallel and spaced apart from each other, the turntable β includes at least one pair of oppositely disposed turntables, the center of the turntable β is disposed outside the edge of the turntable γ and the turntable β supports the turntable γ, and the edge of the turntable α is connected with the edge of the turntable β to support the turntable β.

10. The calibration testing method of claim 9, wherein the nonmagnetic three-axis turntable further comprises a supporting frame, the supporting frame comprises a supporting surface and a supporting column for fixing and supporting the supporting surface, and the turntable α is rotatably disposed on the supporting surface of the supporting frame.

11. The calibration testing method according to claim 10, wherein the magnetometer is fixed at a center position of the turntable γ, and a center of the magnetometer coincides with a center of the turntable γ and rotates with the rotation of the turntable γ.

12. A magnetometer alternating current orthogonality calibration testing device is characterized by comprising:

the calibration equipment is used for generating an alternating-current magnetic field;

the nonmagnetic three-axis turntable is used for fixing the magnetometer and placing the nonmagnetic three-axis turntable fixed with the magnetometer in a uniform area of the alternating-current magnetic field, and the nonmagnetic three-axis turntable drives the magnetometer to rotate in a plurality of different directions in the alternating-current magnetic field;

and the data processing unit is electrically connected with the magnetometer and used for receiving the output data of the alternating current magnetic field detected by the magnetometer in each azimuth in recording time, and analyzing and processing the output data, wherein the recording time is not less than 1 min.

13. The calibration test device according to claim 12, wherein the amplitude of the alternating magnetic field generated by the calibration apparatus is in the range of 0nT to 100000nT, and the frequency is in the range of 0.0001Hz to 100 khz.

14. The calibration test device of claim 12, wherein the calibration equipment comprises a three-axis magnetic field coil, a magnetic field interference cancellation system, and a three-way constant current power supply,

wherein a current is applied to the tri-axial magnetic field coil to form the alternating magnetic field;

the magnetic field interference elimination system comprises a triaxial compensation coil, an optical pump magnetometer and an interference magnetic field compensation control system, and is used for eliminating the interference of an environmental magnetic field to the magnetic field.

15. The calibration testing device of claim 12, wherein the nonmagnetic three-axis turntable comprises:

a horizontally disposed turntable α;

a turntable gamma which is positioned above the turntable α and is also horizontally arranged, and

a turntable β disposed perpendicular to the turntable α and the turntable γ;

wherein the turntable α and the turntable γ are disposed in parallel and spaced apart from each other, the turntable β includes at least one pair of oppositely disposed turntables, the center of the turntable β is disposed outside the edge of the turntable γ and the turntable β supports the turntable γ, and the edge of the turntable α is connected with the edge of the turntable β to support the turntable β.

16. The calibration testing device of claim 15, wherein the nonmagnetic three-axis turntable further comprises a support portion, the support portion comprises a support surface and a support pillar for fixing and supporting the support surface, and the turntable α is rotatably disposed on the support surface of the support frame.

17. The calibration test device according to claim 15, wherein the magnetometer is fixed at a central position of the turntable γ so as to rotate with the turntable γ.

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