CN104049228B - Magnetic sensor dynamic model calibration method - Google Patents
Magnetic sensor dynamic model calibration method Download PDFInfo
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- CN104049228B CN104049228B CN201410232153.9A CN201410232153A CN104049228B CN 104049228 B CN104049228 B CN 104049228B CN 201410232153 A CN201410232153 A CN 201410232153A CN 104049228 B CN104049228 B CN 104049228B
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Abstract
The invention discloses a magnetic sensor dynamic model calibration method. The magnetic sensor dynamic model calibration method comprises the steps that a long and straight wire is arranged in the central axis of a magnetic shielding cylinder, a high-precision magnetic sensor is selected and arranged in the magnetic shielding cylinder, and feedback signals are provided for a signal source; position parameters of the magnetic sensor to be calibrated are measured; the signal source sends out a typical signal, and corresponding output signals are connected; an excitation input magnetic field of the magnetic sensor to be calibrated is calculated through the position parameters, the excitation input magnetic field and magnetic field response output signals are processed, and dynamic characteristics of the magnetic sensor to be calibrated are calibrated. The magnetic sensor dynamic model calibration method solves the problem that in the prior art, due to the fact that a standard high-frequency alternating input excitation magnetic field cannot be provided for the magnetic sensor to be calibrated, the requirement for measurement accuracy cannot be met in the method due to the phenomena of response hysteresis and distortion on the measured magnetic signals by the magnetic sensor.
Description
Technical field
The invention belongs to the calibration technique field of Magnetic Sensor, and in particular to a kind of dynamic model demarcation side of Magnetic Sensor
Method.
Background technology
Magnetic Sensor surveys magnetic precision not only to be influenceed by scale factor, but also by Magnetic Sensor dynamic response model
Influence, thus, in magnetic signal field of detecting, accurate detection dynamic magnetic signal is particularly important.However, existing Magnetic Sensor
Demarcation is concentrated mainly on static characteristic test calibration aspect, and demarcates less to its dynamic characteristic, to find out its cause, being current mark
Quasi- magnetic field generator is that, due to being influenceed by coil high-frequency impedance, it is difficult to produce based on current source and coil combination scheme
The high-frequency alternating magnetic field of standard.The patent of Application No. 201010172592.7 and Application No. 201110343444.1 is public respectively
A kind of inertia based on genetic algorithm/geomagnetic sensor scaling method and a kind of method of calibrating three-axle magnetic sensor have been opened,
But this two methods belongs to static environment subscript determines to improve survey magnetic precision on scale factor.In tested magnetic field signal dynamic
Under change condition, cannot meet because Magnetic Sensor is sluggish to tested magnetic signal response, distortion phenomenon ultimately results in the above method
The requirement of certainty of measurement.
The content of the invention
Dynamic model scaling method it is an object of the invention to propose a kind of Magnetic Sensor, to solve prior art
In, due to the high-frequency alternating input stimulus magnetic field of standard cannot be provided for Magnetic Sensor to be calibrated, and cause tested magnetic field to be believed
Under number dynamic changing condition, because Magnetic Sensor is sluggish to tested magnetic signal response, distortion phenomenon ultimately result in the above method without
Method meets the problem of the requirement of certainty of measurement.
The technical scheme is that：A kind of dynamic model scaling method of Magnetic Sensor is provided, it is described for demarcating
Method includes：One long straight conductor is placed on the central axis of magnetic screen, cylinder, the long straight conductor resistance and signal source after tested
Conducting；It is placed in the magnetic shielding cylinder from a high accuracy Magnetic Sensor, it is long described in the high accuracy Magnetic Sensor real-time detection
The magnetic signal that straight wire is produced, and the magnetic signal is converted into electric signal, feed back to the signal source as amount of negative feedback；Will
Magnetic Sensor to be calibrated is placed in the magnetic shielding cylinder to be had at the position of certain distance with the long straight conductor；Treated described in measurement
Demarcate the location parameter of Magnetic Sensor；The signal source provides type signal for the long straight conductor；Gather the test resistance
The magnetic responsiveness output signal of the voltage signal at two ends and the Magnetic Sensor to be calibrated；Calculate the Magnetic Sensor to be calibrated
Excitation input magnetic field；The treatment excitation input magnetic field and Magnetic Sensor response output signal, demarcate magnetic sensing to be calibrated
The dynamic characteristic of device.
In some optional embodiments, the location parameter of the measurement Magnetic Sensor to be calibrated includes：The letter
Number source provides continuous current excitation signal for the long straight conductor；Gather the voltage signal at the test resistance two ends and described to be calibrated
The output voltage signal of Magnetic Sensor；The location parameter is calculated by Biot-Savart law.
In some optional embodiments, the location parameter includes the Magnetic Sensor to be calibrated and the long straight conductor
Vertical range, and the Magnetic Sensor sensitive axes to be calibrated and the long straight conductor angle.
In some optional embodiments, the type signal swept-frequency signal that the signal source is provided for the long straight conductor,
By the location parameter, the excitation input magnetic field of the Magnetic Sensor to be calibrated is calculated.
In some optional embodiments, the signal source is step excitation for the type signal that the long straight conductor is provided
Signal, by the location parameter, calculates the excitation input magnetic field of the Magnetic Sensor to be calibrated.
In some optional embodiments, the high accuracy Magnetic Sensor is less than institute with the vertical range of the long straight conductor
State magnetic shielding cylinder diameter 0.1 times, the high accuracy Magnetic Sensor is the magnetic with the horizontal range of the magnetic shielding cylinder oral area
/ 2nd of shielding cylinder length.
In some optional embodiments, the Magnetic Sensor to be calibrated is less than institute with the vertical range of the long straight conductor
State magnetic shielding cylinder diameter 0.1 times, the Magnetic Sensor to be calibrated is the magnetic with the horizontal range of the magnetic shielding cylinder oral area
/ 2nd of shielding cylinder length.
Another object of the present invention is to propose a kind of dynamic model scaling method system for realizing Magnetic Sensor, bag
Magnetic shielding cylinder, long straight conductor and Magnetic Sensor to be calibrated are included, the long straight conductor is placed on the central axis of the magnetic shielding cylinder；
Resistance is turned on the long straight conductor with the signal source after tested, is also placed with for being the signal source in the magnetic shielding cylinder
The high accuracy Magnetic Sensor of amount of negative feedback is provided；The system also include for detect the test resistance both end voltage with it is described
The harvester of Magnetic Sensor output response signal to be calibrated.
In some optional embodiments, permalloy, ferronickel conjunction of the magnetic shielding cylinder for material selection high magnetic permeability
The cylinder on the face of cylinder that gold etc. is made.
In some optional embodiments, the length of the magnetic shielding cylinder 1 is 0.5 meter to 1 meter.
Beneficial effect：Magnetic Sensor is produced as using the shielded tube and long straight conductor of high magnetic permeability the magnetic sensing is provided
The standard high frequency alternating excitation magnetic field wanted needed for device calibration process, meets Magnetic Sensor certainty of measurement under dynamic environment
It is required that, simple structure.
Brief description of the drawings
With reference to specific accompanying drawing, the present invention is described in further detail.
Fig. 1 is a kind of schematic flow sheet of the dynamic model scaling method of Magnetic Sensor of the invention；
Fig. 2 is the step response curve of the output when Magnetic Sensor input signal to be calibrated is step signal；
Fig. 3 is high accuracy Magnetic Sensor negative-feedback principle schematic diagram；
Fig. 4 is the amplitude versus frequency characte when Magnetic Sensor input signal to be calibrated is swept-frequency signal；
Fig. 5 is the phase-frequency characteristic when Magnetic Sensor input signal to be calibrated is swept-frequency signal；
Fig. 6 is the present invention for realizing the system schematic of the dynamic model scaling method of Magnetic Sensor；
Fig. 7 is the present invention for illustrating the coordinate system schematic diagram that specific calculating process is set up.
Specific embodiment
To make the object, technical solutions and advantages of the present invention become more apparent, below in conjunction with specific embodiment, and reference
Accompanying drawing, the present invention is described in more detail.As shown in figure 1, the method includes：
101：One long straight conductor is placed on the central axis of magnetic shielding cylinder, the long straight conductor resistance and signal after tested
Source turns on, after the signal source provides electric current for the long straight conductor, around the long straight conductor by generation magnetic field, and institute
State the interference in the maskable earth's magnetic field of magnetic shielding cylinder and external environment magnetic field.
102：It is placed in the magnetic shielding cylinder from a high accuracy Magnetic Sensor, the high accuracy Magnetic Sensor real-time detection
The magnetic signal that the long straight conductor is produced, and the magnetic signal is converted into electric signal, feed back to the letter as amount of negative feedback
Number source.
Be using the high accuracy Magnetic Sensor real-time detection purpose in order that whole magnetic field generation device is closed-loop system,
To more accurately control the electric current in long straight conductor, for example, the factor such as temperature can produce certain influence, the length is caused
The electric current of straight wire is decreased or increased, when the temperature increases, described after setting negative-feedback so as to cause magnetic field to be decreased or increased
Signal source can increase its electric current from the stable magnetic field of generation is made, and reach the purpose of generation standard alternating magnetic field, as shown in Figure 3.
Preferably, the high accuracy Magnetic Sensor is less than magnetic screen footpath simply with the vertical range of the long straight conductor
0.1 times, to prevent from producing influence to the poly- magnetic effect of its internal magnetic field due to the magnetic shielding cylinder.The high accuracy magnetic is passed
Sensor and 1/2nd that the horizontal range of the magnetic shielding cylinder oral area is the magnetic shielding cylinder length, because at 1/2nd
Magnetic field be most standard.
103：Magnetic Sensor to be calibrated is placed in the magnetic shielding cylinder has the position of certain distance with the long straight conductor
Put place.
Preferably, the Magnetic Sensor to be calibrated is less than the magnetic shielding cylinder diameter with the vertical range of the long straight conductor
0.1 times, the Magnetic Sensor to be calibrated and two that the horizontal range of the magnetic shielding cylinder oral area is the magnetic shielding cylinder length
/ mono-.Influence is produced on demarcating to prevent the poly- magnetic effect due to the magnetic shielding cylinder on its internal magnetic field, and two
Magnetic field at/mono- is most standard.
104：The location parameter of the Magnetic Sensor to be calibrated is measured, is subsequently to calculate swashing for the Magnetic Sensor to be calibrated
Input magnetic field is encouraged to prepare.Including：
1041：The signal source provides continuous current excitation signal for the long straight conductor, is produced around the long straight conductor steady
Fixed magnetic field.
1042：Gather the voltage signal at the test resistance two ends and the output voltage letter of the Magnetic Sensor to be calibrated
Number.
1043：Calculate the location parameter of the Magnetic Sensor to be calibrated.The length of the prior measurable magnetic screen sleeve,
And the magnetic induction intensity of Magnetic Sensor present position to be calibrated is can obtain by step 1042, Biot-Savart law is brought into public
Formula, you can obtain corresponding location parameter.
105：The signal source provides type signal for the long straight conductor, while gathering the electricity at the test resistance two ends
The output voltage signal of pressure signal and the Magnetic Sensor to be calibrated, can be by double-channel signal acquisition system or double track oscillographys
Device realizes the collection to corresponding signal.
107：By the signal and the location parameter of the Magnetic Sensor to be calibrated that gather, by Biot-Savart law
The excitation input magnetic field of the Magnetic Sensor to be calibrated can be calculated, the excitation input magnetic field is processed described with what is collected
Magnetic responsiveness output signal, demarcates the dynamic characteristic of Magnetic Sensor to be calibrated.
Wherein, excitation input magnetic field and the magnetic responsiveness output signal can be processed by system identifying method, is obtained
Modulus shape parameter, completes the demarcation to the Magnetic Sensor to be calibrated, and system identifying method belongs to prior art, no longer goes to live in the household of one's in-laws on getting married here
State.
The process of the location parameter for calculating the Magnetic Sensor to be calibrated is further illustrated with reference to specific formula.First
Coordinate system as shown in Figure 7 is set up, by Biot-Savart law：
Formula 1：
Formula 2：
Obtained by formula 1 and formula 2：
Formula 3：
Wherein μ0=4 π × 10-7N/A-2, r represents Magnetic Sensor to be calibrated to the vertical range of long straight conductor；θ1、θ2Respectively
Represent the angle between the sensor to be calibrated and the magnetic shielding cylinder cross-section center axle；I represents the electric current of long straight conductor,
L is the length of the magnetic shielding cylinder.As known to formula 3 is learnt as x, the electric current I in long straight conductor is, it is known that B and r are linear functions closes
It is B=f (r), and the voltage at the test resistance two ends that wherein electric current I can be collected by the harvester is by calculating
Obtain, and the magnetic induction intensity of the Magnetic Sensor present position to be calibrated can be obtained again by the harvester, thus
The vertical range of the Magnetic Sensor to be calibrated and the long straight conductor can be calculated.
As described in Figure 6, location parameter also includes the angle of the Magnetic Sensor sensitive axes to be calibrated and the long straight conductor
θ, if the Standard Magnetic Field Source at the Magnetic Sensor to be calibrated is B, the magnetic field that Magnetic Sensor is measured is B ', then cos θ=B '/B.
As shown in Fig. 2 when the signal source for the long straight conductor provides a step pumping signal, the harvester is adopted
The voltage signal at collection test resistance end and the output voltage signal of the Magnetic Sensor to be calibrated.Using formula 3, wherein L and x, can
Measurement in advance is obtained, and obtains the long straight conductor in the magnetic field of Magnetic Sensor measurement point according to r and θ has been calculated, the magnetic
Field is a typical step signal, and the output signal of the Magnetic Sensor to be calibrated is step magnetic responsiveness curve, by being
System discrimination method Treatment Analysis obtain the time domain dynamic performance model of the Magnetic Sensor to be calibrated.
The swept-frequency signal can be for sine wave, triangular wave, square wave etc., when the signal source for the long straight conductor is provided
Type signal is sine sweep signal, and test resistance both end voltage signal and the magnetic to be calibrated are measured using the harvester
Sensor output signal, is obtained the long straight conductor and is sensed in the magnetic to be calibrated using Biot-sand farr's law, and r and θ
The variation magnetic field of device measurement point, the magnetic field is corresponding sine sweep AC magnetic field signal.The Magnetic Sensor to be calibrated
Output signal is the response curve of sine sweep AC magnetic field.Under to various frequencies difference simple alternating current magnetic fields, analyze
The relation of the frequency, amplitude and phase and excitation field of the steady-state response of the Magnetic Sensor to be calibrated, can obtain and described wait to mark
Determine the frequency response characteristic of Magnetic Sensor, under acting on frequency sweep AC magnetic field, analyze the output letter of the Magnetic Sensor to be calibrated
Number, the frequency response characteristic of Magnetic Sensor can be also obtained, as shown in Figure 4 and Figure 5, experimental data refers to that reality is treated to described in figure
The value of calibration sensor measurement, fitting data refers to the curve fitted by the System Discrimination means.As shown in fig. 6, one
System kind for realizing described scaling method, including magnetic shielding cylinder 1, long straight conductor 2 and inside the magnetic shielding cylinder 1
Magnetic Sensor to be calibrated 3, the long straight conductor 2 is placed on the central axis of the magnetic shielding cylinder 1.The long straight conductor 2 is passed through
Test resistance 4 is turned on the signal source 5, is also placed with the magnetic shielding cylinder 1 for for the signal source 5 provides negative-feedback
The high accuracy Magnetic Sensor 6 of amount.The system is also included for detecting the both end voltage of the test resistance 4 with the magnetic to be calibrated
The harvester 7 of the output response signal of sensor 3.
Preferably, the high accuracy Magnetic Sensor is less than the magnetic shielding cylinder diameter with the vertical range of the long straight conductor
0.1 times, to prevent from producing influence to the poly- magnetic effect of its internal magnetic field due to the magnetic shielding cylinder.The high accuracy magnetic is passed
Sensor and 1/2nd that the horizontal range of the magnetic shielding cylinder oral area is the magnetic shielding cylinder length, because at 1/2nd
Magnetic field be most standard.
Preferably, the Magnetic Sensor to be calibrated is less than the magnetic shielding cylinder diameter with the vertical range of the long straight conductor
0.1 times, the Magnetic Sensor to be calibrated and two that the horizontal range of the magnetic shielding cylinder oral area is the magnetic shielding cylinder length
/ mono-.Influence is produced on demarcating to prevent the poly- magnetic effect due to the magnetic shielding cylinder on its internal magnetic field, and two
Magnetic field at/mono- is most standard.
In some optional embodiments, the harvester 7 is double-channel signal acquisition system or dual trace oscilloscope.
In some optional embodiments, permalloy, ferronickel conjunction of the magnetic shielding cylinder for material selection high magnetic permeability
The cylinder on the face of cylinder that gold etc. is made, the magnetic shielding cylinder length is 0.5 meter to 1 meter optimal, the high-frequency alternating magnetic field of generation
More standard.
It should also be appreciated by one skilled in the art that the various illustrative box, the mould that are described with reference to the embodiments herein
Block, circuit and algorithm steps can be implemented as electronic hardware, computer software or its combination.In order to clearly demonstrate hardware and
Interchangeability between software, is carried out to various illustrative parts, frame, module, circuit and step around its function above
It is generally described.Hardware is implemented as this function and is also implemented as software, depending on specific application and to whole
The design constraint that system is applied.Those skilled in the art can be directed to each application-specific, be realized in the way of accommodation
Described function, but, it is this to realize that decision-making should not be construed as the protection domain away from the disclosure.
Claims (8)
1. the dynamic model scaling method of a kind of Magnetic Sensor, it is characterised in that the method for demarcating includes：
One long straight conductor is placed on the central axis of magnetic shielding cylinder, resistance is turned on the long straight conductor with signal source after tested；
It is placed in the magnetic shielding cylinder from a high accuracy Magnetic Sensor, it is long straight described in the high accuracy Magnetic Sensor real-time detection
The magnetic signal that wire is produced, and the magnetic signal is converted into electric signal, feed back to the signal source as negative-feedback；
Magnetic Sensor to be calibrated is placed in the magnetic shielding cylinder, the Magnetic Sensor to be calibrated is vertical with the long straight conductor
Distance less than 0.1 times of the magnetic shielding cylinder diameter, the level of the Magnetic Sensor to be calibrated and the magnetic shielding cylinder oral area away from
From 1/2nd for the magnetic shielding cylinder length；
Measure the location parameter of the Magnetic Sensor to be calibrated；
The signal source provides type signal, typical case's letter that the signal source is provided for the long straight conductor for the long straight conductor
Number it is swept-frequency signal, by the location parameter, calculates the excitation input magnetic field of the Magnetic Sensor to be calibrated；Collection institute
State the voltage signal at test resistance two ends and the magnetic responsiveness output signal of the Magnetic Sensor to be calibrated；
The excitation for calculating the Magnetic Sensor to be calibrated by the location parameter is input into magnetic field, processes the excitation input magnetic field
Output signal is responded with the Magnetic Sensor, the dynamic characteristic of Magnetic Sensor to be calibrated is demarcated.
2. such as a kind of dynamic model scaling method of Magnetic Sensor according to claim 1, it is characterised in that the measurement institute
The location parameter for stating Magnetic Sensor to be calibrated includes：
The signal source provides continuous current excitation signal for the long straight conductor；
Gather the voltage signal at the test resistance two ends and the output voltage signal of the Magnetic Sensor to be calibrated；
The location parameter is calculated by Biot-Savart law.
3. a kind of dynamic model scaling method of Magnetic Sensor according to claim 2, it is characterised in that the location parameter
Vertical range including the Magnetic Sensor to be calibrated with the long straight conductor, and the Magnetic Sensor sensitive axes to be calibrated with
The angle of the long straight conductor.
4. the dynamic model scaling method of a kind of Magnetic Sensor according to claim 3, it is characterised in that the signal source is
The type signal that the long straight conductor is provided is step excitation signal, by the location parameter, is calculated described to be calibrated
The excitation input magnetic field of Magnetic Sensor.
5. according to claim 3 or 4 a kind of Magnetic Sensor dynamic model scaling method, it is characterised in that it is described high-precision
Degree Magnetic Sensor is less than 0.1 times of the magnetic shielding cylinder diameter with the vertical range of the long straight conductor, and the high accuracy magnetic is passed
Sensor and 1/2nd that the horizontal range of the magnetic shielding cylinder oral area is the magnetic shielding cylinder length.
6. a kind of system for realizing scaling method as claimed in claim 1, it is characterised in that including magnetic shielding cylinder (1),
Long straight conductor (2) and Magnetic Sensor to be calibrated (3), the long straight conductor (2) are placed in the central axis of the magnetic shielding cylinder (1)
On；Resistance (4) is turned on the long straight conductor (2) with the signal source (5) after tested, is also placed with the magnetic shielding cylinder (1)
High accuracy Magnetic Sensor (6) for providing amount of negative feedback for the signal source (5)；The system also includes described for detecting
The harvester (7) of test resistance (4) both end voltage and Magnetic Sensor (3) output response signal to be calibrated.
7. system as claimed in claim 6, it is characterised in that the magnetic shielding cylinder (1) is the perm of material selection high magnetic permeability
The cylinder on the face of cylinder that alloy, dilval are made.
8. system as claimed in claim 7, it is characterised in that the length of the magnetic shielding cylinder (1) is 0.5 meter to 1 meter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410232153.9A CN104049228B (en) | 2014-05-28 | 2014-05-28 | Magnetic sensor dynamic model calibration method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410232153.9A CN104049228B (en) | 2014-05-28 | 2014-05-28 | Magnetic sensor dynamic model calibration method |
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| CN104049228B true CN104049228B (en) | 2017-05-17 |
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| JP5707021B2 (en) * | 2008-09-30 | 2015-04-22 | 株式会社日立ハイテクノロジーズ | Magnetic field measuring device |
| CN203324462U (en) * | 2013-06-20 | 2013-12-04 | 苏州大学 | System for performing test and calibration on magnetic sensors |
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