A magnetostrictive self-calibration system and method

Abstract

The invention discloses a magnetostrictive self-calibration system and method, belonging to the technical field of sensor calibration. The invention performs a primary calibration on the measured value of a magnetostrictive displacement sensor through the average speed in a sub-range section where a magnetic ring is located and the range that has passed the sub-range section, and then performs a secondary calibration by compensating for the hysteresis effect through a Preisach model. Finally, a fitting curve is obtained by a least square method in combination with the measured data of a magnetic scale, and the measured value is calibrated three times according to the curve slope and intercept of the fitting curve, so as to improve the measurement accuracy and stability of the magnetostrictive displacement sensor and the accuracy of the calibration.

Description

Technical Field

[0001] The invention relates to the technical field of sensor calibration, in particular to a magnetostrictive self-calibration system and method. Background Art

[0002] During the displacement measurement process of the magnetostrictive displacement sensor, the measurement accuracy of the magnetostrictive displacement sensor will be directly affected due to the limitation of the production process level of the components, and the sensor measurement value will show obvious drift, that is, the measurement accuracy is low.

[0003] In the prior art, the calibration of the measured value of the magnetostrictive displacement sensor is often limited to one calibration, and such a calibration result is not stable and the calibration accuracy is not high enough. Summary of the invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a magnetostrictive self-calibration method, which is characterized by comprising the following steps:

[0005] The measuring range of the magnetostrictive displacement sensor is obtained and averagely segmented according to the measuring range to obtain N sub-range segments;

[0006] Obtaining the initial time and the end time of the magnetic ring in each sub-range segment, and dividing each sub-range segment into a corresponding time zone according to the initial time and the end time of each sub-range segment;

[0007] Divide the corresponding time zone according to each sub-range segment, determine the sub-range segment where the magnetic ring is at the current moment, and record the number q of sub-range segments that the magnetic ring has completely passed through;

[0008] Calculate the average speed V of the magnetic ring in the current sub-range segment according to the initial time and the end time corresponding to the current sub-range segment;

[0009] Calculate the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through;

[0010] The first calibration displacement is compensated by the Preisach model to obtain a second calibration displacement S2;

[0011] Through the above steps, a plurality of different second calibration displacements are obtained, and at the same time, the comparative displacement S3 corresponding to the magnetic ring at the position of each second calibration displacement is obtained through the magnetic scale;

[0012] A fitting curve is constructed by the least square method using each second calibration displacement as the abscissa and the corresponding comparison displacement S3 as the ordinate, and a curve slope k and an intercept b are obtained according to the fitting curve;

[0013] The final calibration displacement S4 is calculated based on the slope k and intercept b of the curve for the real-time second calibration displacement.

[0014] Furthermore, the initial moment of the magnetic ring in each sub-range segment is obtained, specifically, the moment when the magnetic ring reaches the starting position of each sub-range segment is detected by a magnetic scale or a laser interferometer; the ending moment of the magnetic ring in each sub-range segment is obtained, specifically, the moment when the magnetic ring reaches the end position of each sub-range segment is detected by a magnetic scale or a laser interferometer.

[0015] Furthermore, the average speed V of the magnetic ring in the current sub-range segment is calculated according to the initial time and the end time corresponding to the current sub-range segment, specifically:

[0016] ;

[0017] Where L represents the range of the sub-range segment, Indicates the end time of the current sub-range segment. Indicates the initial time of the current sub-range segment.

[0018] Furthermore, the calculation of the first calibration displacement S1 corresponding to the magnetic ring at the current moment is specifically:

[0019] ;

[0020] Among them, t represents the current time.

[0021] Furthermore, compensating the first calibration displacement by the Preisach model to obtain the second calibration displacement S2 specifically includes the following steps:

[0022] Set the maximum value of the preset external magnetic field strength ;

[0023] Calculate the Preisach kernel function value based on the current magnetic field strength value H ;

[0024] Calculate the magnetization intensity at the current magnetic field value ;

[0025] According to the current magnetic field value The magnetization intensity under The first calibration displacement is compensated to obtain a second calibration displacement S2.

[0026] Further, the Preisach kernel function value is calculated according to the current magnetic field strength value H , specifically:

[0027] ;

[0028] ;

[0029] Where H represents the current magnetic field strength value, which is measured and obtained by the magnetic field sensor. represents the hysteresis width, m and b represent preset coefficients.

[0030] Furthermore, the calculation of the magnetization intensity under the current magnetic field value , specifically:

[0031] .

[0032] Further, the current magnetic field value The magnetization intensity under The first calibration displacement is compensated to obtain a second calibration displacement S2, specifically:

[0033] ;

[0034] in, Indicates the preset conversion factor.

[0035] Furthermore, the final calibration displacement S4 is obtained by calculating the real-time second calibration displacement according to the curve slope k and the intercept b, specifically: S4=k S2+b.

[0036] The present invention also provides a magnetostrictive self-calibration system, comprising: a sub-range segment division module, a time region division module, a first analysis module, a first calibration module, a second calibration module, a second analysis module and a final calibration module;

[0037] The sub-range segment division module is used to averagely segment the range of the magnetostrictive displacement sensor to obtain N sub-range segments, and mark the starting position and end position of each sub-range segment;

[0038] The time region division module is used to obtain the initial time and the end time of the magnetic ring in each sub-range segment, and divide the corresponding time region into each sub-range segment according to the initial time and the end time of each sub-range segment;

[0039] The first analysis module is used to divide the corresponding time zone according to each sub-range segment, determine the sub-range segment where the magnetic ring is located at the current moment, and record the number q of sub-range segments that the magnetic ring has completely passed through, and calculate the average speed V of the magnetic ring in the current sub-range segment according to the initial moment and the end moment corresponding to the current sub-range segment;

[0040] The first calibration module is used to calculate the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through;

[0041] The second calibration module is used to compensate the first calibration displacement by using a Preisach model to obtain a second calibration displacement S2;

[0042] The second analysis module is used to obtain a plurality of different second calibration displacements and comparison displacements S3, and to construct a fitting curve by the least square method with each second calibration displacement as the abscissa and the corresponding comparison displacement S3 as the ordinate, and to obtain a curve slope k and an intercept b according to the fitting curve, wherein the comparison displacement is a corresponding displacement value measured by the magnetic scale according to the magnetic ring at a position corresponding to the second calibration displacement;

[0043] The final calibration module is used to calculate the final calibration displacement S4 according to the curve slope k and the intercept b of the real-time second calibration displacement, S4=k S2+b.

[0044] Furthermore, the magnetostrictive self-calibration system is applied to a magnetostrictive self-calibration device, wherein the magnetostrictive self-calibration device includes a control display platform, a data acquisition platform and a test platform.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The present invention performs a primary calibration on the measured value of the magnetostrictive displacement sensor by using the average speed in the sub-range section where the magnetic ring is located and the range that has passed the sub-range section, and then performs a secondary calibration by compensating the hysteresis effect through the Preisach model. Finally, a fitting curve is obtained by the least square method in combination with the measured data of the magnetic scale, and the measured value is calibrated three times according to the curve slope and intercept of the fitting curve, thereby improving the measurement accuracy and stability of the magnetostrictive displacement sensor and the accuracy of the calibration.

[0047] By compensating the hysteresis effect through the Preisach model, the nonlinear error caused by hysteresis can be reduced and the accuracy of the measurement results can be improved;

[0048] Finally, the magnetic scale is used to obtain accurate position data as a reference benchmark, and the least squares method is used to fit an optimal curve, which represents the relationship between the actual output and the ideal output of the magnetostrictive displacement sensor. The error of the magnetostrictive displacement sensor is corrected to improve its overall measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0050] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0051] Figure 1 is a flow chart of a magnetostrictive self-calibration method of the present invention;

[0052] Figure 2 This is a flowchart of step T6 in a magnetostrictive self-calibration method of the present invention, in which the first calibration displacement is compensated by the Preisach model to obtain the second calibration displacement S2;

[0053] Figure 3 It is a structural block diagram of a magnetostrictive self-calibration system of the present invention;

[0054] Figure 4 It is an overall structural diagram of a magnetostrictive self-calibration device of the present invention;

[0055] Figure 5 yes Figure 4 Enlarged view of point A. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0058] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0059] Embodiment 1

[0060] See also Figure 1 As shown, the present invention provides a magnetostrictive self-calibration method, which specifically includes the following steps:

[0061] T1. Obtain the range of the magnetostrictive displacement sensor and divide it into N sub-range segments according to the range, and mark the starting position and end position of each sub-range segment;

[0062] T2, obtaining the initial time and end time of the magnetic ring in each sub-range segment, and dividing each sub-range segment into a corresponding time zone according to the initial time and end time of each sub-range segment;

[0063] T3. Divide the corresponding time zone according to each sub-range segment, determine the sub-range segment where the magnetic ring is at the current moment, and record the number q of sub-range segments that the magnetic ring has completely passed through;

[0064] T4, calculating the average speed V of the magnetic ring in the current sub-range segment according to the initial time and the end time corresponding to the current sub-range segment;

[0065] T5, calculating the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through;

[0066] T6. Compensating the first calibration displacement by using the Preisach model to obtain a second calibration displacement S2;

[0067] T7. Obtain multiple different second calibration displacements through the above steps, and at the same time obtain the comparative displacement S3 corresponding to the magnetic ring at the position of each second calibration displacement through the magnetic scale;

[0068] T8, constructing a fitting curve by the least square method with each second calibration displacement as the abscissa and the corresponding comparison displacement S3 as the ordinate, and obtaining the curve slope k and intercept b according to the fitting curve;

[0069] T9, calculate the final calibration displacement S4 based on the curve slope k and intercept b for the real-time second calibration displacement:

[0070] S4=k S2+b.

[0071] After completing the secondary calibration through the Preisach model, the magnetic scale is used to obtain accurate position data as a reference benchmark, and the least squares method is used to fit an optimal curve to represent the relationship between the actual output and the ideal output of the magnetostrictive displacement sensor, further optimizing the sensor output, reducing errors, and improving overall accuracy.

[0072] For step T1, the range of the magnetostrictive displacement sensor can be obtained by:

[0073] 1. Consult the technical documentation provided by the manufacturer, such as user manuals, data sheets, or product specifications. These documents usually list the technical parameters of the sensor in detail, including the maximum measurement range.

[0074] 2. Estimate the possible range of the sensor by measuring its physical size. Magnetostrictive displacement sensors usually consist of a waveguide and an external magnetic ring. The length of the waveguide can be used as an approximate indicator of the sensor's range. For example, if the waveguide is 1 meter long, then theoretically the maximum range of the sensor should be close to 1 meter.

[0075] 3. Determine the sensor range through laboratory testing.

[0076] For step T2, the initial moment of the sub-range segment, that is, the instant when the magnetic ring starts to move at the starting position of the corresponding sub-range segment, and the end moment of the sub-range segment, that is, the instant when the magnetic ring is at the end position of the corresponding sub-range segment, are also the initial moment of the magnetic ring in the next sub-range segment.

[0077] The corresponding time zone is divided for each sub-range segment according to the initial time and the end time of each sub-range segment. For example, the initial time and the end time of the i-th sub-range segment are respectively and ,but to is the time region of the ith sub-range segment.

[0078] In some embodiments, the initial moment and the end moment of the magnetic ring in each sub-range segment are obtained by selectively detecting the starting position and the end position of the magnetic ring arriving at each sub-range segment through a magnetic scale or a laser interferometer, thereby recording the initial moment and the end moment of the magnetic ring in each sub-range segment.

[0079] For step T3, the number of sub-range segments q that have been completely passed is recorded as follows: assuming that the sub-range segment where the magnetic ring is located at the current moment is the i-th segment, then the number of sub-range segments that the magnetic ring has completely passed is q=i-1. In step T1, N sub-range segments are obtained by average segmentation according to the range, and the starting position of the first sub-range segment is the initial position of the magnetic ring.

[0080] For step T4, the average speed V of the magnetic ring in the current sub-range segment is calculated according to the initial time and the end time corresponding to the current sub-range segment, specifically:

[0081] ;

[0082] Where L represents the range of the sub-range segment, Indicates the end time of the current sub-range segment. Indicates the initial time of the current sub-range segment.

[0083] For step T5, the first calibration displacement S1 corresponding to the magnetic ring at the current moment is calculated according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through, specifically:

[0084] ;

[0085] Among them, t represents the current time.

[0086] See also Figure 2 As shown, for step T6, compensating the first calibration displacement by the Preisach model to obtain the second calibration displacement S2 specifically includes the following steps:

[0087] U1, set the maximum value of the preset external magnetic field strength .

[0088] The preset maximum value of the external magnetic field intensity is manually predicted and set in advance according to the material properties and application scenarios of the magnetostrictive sensor.

[0089] U2, calculate the Preisach kernel function value according to the current magnetic field strength value H :

[0090] ;

[0091] ;

[0092] Where H represents the current magnetic field strength value, which is measured and obtained by the magnetic field sensor. represents the hysteresis width, that is, the change in magnetic field required to recover from the saturation state to the initial state, and m and b both represent preset coefficients.

[0093] The preset coefficients m and b are specifically obtained by performing a magnetization cycle experiment on the magnetostrictive displacement sensor, specifically placing it in a zero magnetic field environment, gradually increasing the external magnetic field strength, and gradually reducing the magnetic field strength after reaching the preset maximum external magnetic field strength. The point where the external magnetic field strength decreases from being greater than the preset maximum external magnetic field strength to just no longer satisfying the Preisach kernel function value of 1 is recorded as a turning point, and the external magnetic field strength h corresponding to the turning point is recorded. At this time Repeat the above process several times to obtain multiple turning points and calculate different , according to the preset maximum value of the external magnetic field strength and multiple The calculation is performed with preset coefficients m and b.

[0094] Preisach kernel function value Defines the current magnetic field strength value H and the preset maximum value of the applied magnetic field strength Is the material in a saturated state? When , it means that the current magnetic field strength value is greater than the preset maximum value of the external magnetic field strength, the magnetic material of the magnetostrictive displacement sensor is in a completely saturated state, and the Preisach kernel function value is 1.

[0095] U3, calculate the current magnetic field value The magnetization intensity under :

[0096] ;

[0097] U4, according to the current magnetic field value The magnetization intensity under The first calibration displacement is compensated to obtain a second calibration displacement S2:

[0098] ;

[0099] in, Indicates the preset conversion factor.

[0100] The preset conversion coefficient is used to convert the change of magnetization intensity into the change of displacement, and is obtained by artificial pre-experimental calibration.

[0101] After the initial calibration of the magnetostrictive sensor, the main purpose of recalibrating it using the Preisach model is to further eliminate or reduce the errors caused by the hysteresis effect. The hysteresis effect refers to the fact that the response of a material to an external stimulus (such as a magnetic field or stress) is not immediate and completely reversible, but rather exhibits a lag during cyclic loading and unloading. Although the initial calibration can improve the basic accuracy of the sensor, the output of the sensor may still have certain nonlinear errors due to the hysteresis effect. By using the Preisach model, these nonlinear errors can be further corrected to improve the measurement accuracy of the sensor.

[0102] The Preisach model is a mathematical tool used to describe and simulate the hysteresis phenomenon. It models the hysteresis loop based on a set of threshold functions and weight functions. By determining these thresholds and weights by measurement or experiment, a mathematical model that can accurately predict the hysteresis effect can be constructed. Applying the Preisach model in magnetostrictive displacement sensors can achieve accurate correction of the sensor output signal, thereby improving its overall performance.

[0103] Embodiment 2

[0104] See also Figure 3 As shown, the present invention also provides a magnetostrictive self-calibration system, comprising:

[0105] A sub-range segment division module, a time region division module, a first analysis module, a first calibration module, a second calibration module, a second analysis module, a final calibration module and a central processing unit that is communicatively connected to the above modules.

[0106] The sub-range segment division module is used to averagely segment the range of the magnetostrictive displacement sensor to obtain N sub-range segments, and mark the starting position and end position of each sub-range segment.

[0107] The time region division module is used to obtain the initial time and the end time of the magnetic ring in each sub-range segment, and divide the corresponding time region into each sub-range segment according to the initial time and the end time of each sub-range segment.

[0108] The first analysis module is used to divide the corresponding time area according to each sub-range segment, determine the sub-range segment where the magnetic ring is at the current moment, and record the number q of sub-range segments that the magnetic ring has completely passed through, and calculate the average speed V of the magnetic ring in the current sub-range segment according to the initial moment and end moment corresponding to the current sub-range segment.

[0109] The first calibration module is used to calculate the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment and the number of sub-range segments that the magnetic ring has completely passed through.

[0110] The second calibration module is used to compensate the first calibration displacement by using a Preisach model to obtain a second calibration displacement S2.

[0111] The second analysis module is used to obtain multiple different second calibration displacements and comparison displacements S3, and construct a fitting curve by the least squares method with each second calibration displacement as the horizontal coordinate and the corresponding comparison displacement S3 as the vertical coordinate. The curve slope k and intercept b are obtained according to the fitting curve. The comparison displacement is the corresponding displacement value measured by the magnetic scale when the magnetic ring is at the position corresponding to the second calibration displacement.

[0112] The final calibration module is used to calculate the final calibration displacement S4 according to the curve slope k and intercept b of the real-time second calibration displacement, S4=k S2+b.

[0113] The first analysis module calculates the average speed V of the magnetic ring in the current sub-range segment according to the initial time and the end time corresponding to the current sub-range segment, specifically:

[0114] ;

[0115] Where L represents the range of the sub-range segment, Indicates the end time of the current sub-range segment. Indicates the initial time of the current sub-range segment.

[0116] The first calibration module calculates the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through, specifically:

[0117] ;

[0118] Among them, t represents the current time.

[0119] The second calibration module compensates the first calibration displacement by the Preisach model to obtain a second calibration displacement S2, specifically:

[0120] U1, set the maximum value of the preset external magnetic field strength .

[0121] The preset maximum value of the external magnetic field intensity is manually predicted and set in advance according to the material properties and application scenarios of the magnetostrictive sensor.

[0122] U2, calculate the Preisach kernel function value according to the current magnetic field strength value H :

[0123] ;

[0124] ;

[0125] Where H represents the current magnetic field strength value, which is measured and obtained by the magnetic field sensor. represents the hysteresis width, that is, the change in magnetic field required to recover from the saturation state to the initial state, and m and b both represent preset coefficients.

[0126] U3, calculate the current magnetic field value The magnetization intensity under :

[0127] ;

[0128] U4, according to the current magnetic field value The magnetization intensity under The first calibration displacement is compensated to obtain a second calibration displacement S2:

[0129] ;

[0130] in, Indicates the preset conversion factor.

[0131] The preset conversion coefficient is used to convert the change of magnetization intensity into the change of displacement, and is obtained by artificial pre-experimental calibration.

[0132] Embodiment 3

[0133] See also Figure 4 As shown, a magnetostrictive self-calibration device provided by the present invention includes a control and display platform 41 , a data acquisition platform 42 and a test platform 45 .

[0134] The control and display platform 41 and the test platform 45 are electrically connected to the data acquisition platform 42 .

[0135] The control display platform 42 applies the above-mentioned magnetostrictive self-calibration system.

[0136] See also Figure 5 As shown, the test platform 45 includes a permanent magnetic ring 51 , a magnetostrictive sensor mounting position 52 , a magnetic sensor mounting position 53 and a magnetic ring fixing frame 54 .

[0137] During calibration, the magnetostrictive sensor and the magnetic sensor are first installed on the magnetostrictive sensor installation position and the magnetic sensor installation position respectively. The magnetic sensor may use a magnetic scale. The magnetostrictive sensor and the magnetic sensor are both electrically connected to the data acquisition platform 42. When the permanent magnetic ring 51 moves on the magnetic ring fixing frame 54, the data acquisition platform 42 collects the measurement data of the magnetostrictive sensor and the magnetic sensor and transmits it to the control and display platform 41. The control and display platform 41 then calibrates the magnetostrictive sensor through the magnetostrictive self-calibration method used by the above-mentioned magnetostrictive self-calibration system.

[0138] Embodiment 4

[0139] The present invention also provides an electronic device, including: a processor, a sending device, an input device, an output device and a memory. The processor can be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit, or one or more integrated circuits, and is used to execute relevant programs to implement the technical solution provided in the embodiment of the present application. The memory can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device or a random access memory (RAM), and is used to store computer program code. The computer program code includes computer instructions. When the processor executes the computer instructions, the electronic device executes a method as described in any of the above possible implementation methods.

[0140] Embodiment 5

[0141] The present invention also provides a computer-readable storage medium, in which a computer program is stored. The computer program includes program instructions. When the program instructions are executed by a processor of an electronic device, the processor executes a method as described in any possible implementation manner.

[0142] The beneficial effects of the present invention are:

[0143] The present invention performs a primary calibration on the measured value of the magnetostrictive displacement sensor by using the average speed in the sub-range section where the magnetic ring is located and the range that has passed the sub-range section, and then performs a secondary calibration by compensating for the hysteresis effect through the Preisach model. Finally, a fitting curve is obtained by the least square method in combination with the measurement data of the magnetic scale, and the measured value is calibrated three times according to the curve slope and intercept of the fitting curve, thereby reducing errors from multiple angles, improving the measurement accuracy and stability of the magnetostrictive displacement sensor, and improving the accuracy of calibration.

[0144] By compensating the hysteresis effect through the Preisach model, the nonlinear error caused by hysteresis can be reduced and the accuracy of the measurement results can be improved;

[0145] Finally, the magnetic scale is used to obtain accurate position data as a reference, and the least square method is used to fit an optimal curve, which represents the relationship between the actual output and the ideal output of the magnetostrictive displacement sensor. The error of the magnetostrictive displacement sensor is corrected to improve its overall measurement accuracy.

[0146] Through staged calibration, the sensor output can be further optimized on the basis of eliminating the hysteresis effect, reducing nonlinear errors and ensuring that the sensor can provide accurate and reliable measurement results under different conditions.

[0147] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0148] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit. If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including multiple instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method of each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, referred to as ROM), random access memory (RandomAccess Memory, referred to as RAM), disk or optical disk and other media that can store programs.

[0149] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A magnetostrictive self-calibration method, characterized in that: The following steps are involved: The measuring range of the magnetostrictive displacement sensor is obtained and averagely segmented according to the measuring range to obtain N sub-range segments; Obtaining the initial time and the end time of the magnetic ring in each sub-range segment, and dividing each sub-range segment into a corresponding time zone according to the initial time and the end time of each sub-range segment; Divide the corresponding time zone according to each sub-range segment, determine the sub-range segment where the magnetic ring is at the current moment, and record the number q of sub-range segments that the magnetic ring has completely passed through; Calculate the average speed V of the magnetic ring in the current sub-range segment according to the initial time and the end time corresponding to the current sub-range segment; Calculate the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through; The first calibration displacement is compensated by the Preisach model to obtain a second calibration displacement S2, specifically comprising the following steps: setting a preset maximum value of the external magnetic field strength ; Calculate the Preisach kernel function value according to the current magnetic field strength value H ; Calculate the magnetization intensity under the current magnetic field value ; According to the current magnetic field value The magnetization intensity under Compensating the first calibration displacement to obtain a second calibration displacement S2; The Preisach kernel function value is calculated according to the current magnetic field strength value H , specifically: ； ； Where H represents the current magnetic field strength value, which is measured and obtained by the magnetic field sensor. represents the hysteresis width, m and b2 both represent preset coefficients; Through the above steps, a plurality of different second calibration displacements are obtained, and at the same time, the comparative displacement S3 corresponding to the magnetic ring at the position of each second calibration displacement is obtained through the magnetic scale; A fitting curve is constructed by the least square method using each second calibration displacement as the abscissa and the corresponding comparison displacement S3 as the ordinate, and a curve slope k and an intercept b are obtained according to the fitting curve; The final calibration displacement S4 is calculated based on the slope k and intercept b of the curve for the real-time second calibration displacement.

2. The magnetostrictive self-calibration method according to claim 1, characterized in that: The initial moment of the magnetic ring in each sub-range segment is obtained, specifically, the moment when the magnetic ring reaches the starting position of each sub-range segment is detected by a magnetic scale or a laser interferometer; the ending moment of the magnetic ring in each sub-range segment is obtained, specifically, the moment when the magnetic ring reaches the end position of each sub-range segment is detected by a magnetic scale or a laser interferometer.

3. The magnetostrictive self-calibration method according to claim 1, characterized in that: The average speed V of the magnetic ring in the current sub-range segment is calculated according to the initial time and the end time corresponding to the current sub-range segment, specifically: ； Where L represents the range of the sub-range segment, Indicates the end time of the current sub-range segment. Indicates the initial time of the current sub-range segment.

4. The magnetostrictive self-calibration method according to claim 3, characterized in that: The first calibration displacement S1 corresponding to the calculated magnetic ring at the current moment is specifically: ； Among them, t represents the current time.

5. The magnetostrictive self-calibration method according to claim 1, characterized in that: The calculation of the magnetization intensity under the current magnetic field value , specifically: 。 6. The magnetostrictive self-calibration method according to claim 1, characterized in that: According to the current magnetic field value The magnetization intensity under The first calibration displacement is compensated to obtain a second calibration displacement S2, specifically: ； in, Indicates the preset conversion factor; The final calibration displacement S4 is obtained by calculating the real-time second calibration displacement according to the curve slope k and the intercept b, specifically: S4=k×S2+b.

7. A magnetostrictive self-calibration system, using the magnetostrictive self-calibration method according to any one of claims 1 to 6, characterized in that: include: A sub-range segment division module, a time region division module, a first analysis module, a first calibration module, a second calibration module, a second analysis module and a final calibration module; The sub-range segment division module is used to averagely segment the range of the magnetostrictive displacement sensor to obtain N sub-range segments, and mark the starting position and end position of each sub-range segment; The time region division module is used to obtain the initial time and the end time of the magnetic ring in each sub-range segment, and divide the corresponding time region into each sub-range segment according to the initial time and the end time of each sub-range segment; The first analysis module is used to divide the corresponding time zone according to each sub-range segment, determine the sub-range segment where the magnetic ring is located at the current moment, and record the number q of sub-range segments that the magnetic ring has completely passed through, and calculate the average speed V of the magnetic ring in the current sub-range segment according to the initial moment and the end moment corresponding to the current sub-range segment; The first calibration module is used to calculate the first calibration displacement S1 corresponding to the magnetic ring at the current moment according to the average speed of the magnetic ring in the current sub-range segment, the current moment, and the number of sub-range segments that the magnetic ring has completely passed through; The second calibration module is used to compensate the first calibration displacement by the Preisach model to obtain a second calibration displacement S2, specifically comprising the following steps: setting a preset maximum value of the external magnetic field strength ; Calculate the Preisach kernel function value according to the current magnetic field strength value H ; Calculate the magnetization intensity under the current magnetic field value ; According to the current magnetic field value The magnetization intensity under Compensating the first calibration displacement to obtain a second calibration displacement S2; The Preisach kernel function value is calculated according to the current magnetic field strength value H , specifically: ； ； Where H represents the current magnetic field strength value, which is measured and obtained by the magnetic field sensor. represents the hysteresis width, m and b2 both represent preset coefficients; The second analysis module is used to obtain a plurality of different second calibration displacements and comparison displacements S3, and to construct a fitting curve by the least square method with each second calibration displacement as the abscissa and the corresponding comparison displacement S3 as the ordinate, and to obtain a curve slope k and an intercept b according to the fitting curve, wherein the comparison displacement is a corresponding displacement value measured by the magnetic scale according to the magnetic ring at a position corresponding to the second calibration displacement; The final calibration module is used to calculate the real-time second calibration displacement according to the curve slope k and the intercept b to obtain the final calibration displacement S4, S4=k×S2+b.

8. The magnetostrictive self-calibration system according to claim 7, characterized in that: The magnetostrictive self-calibration system is applied to a magnetostrictive self-calibration device, wherein the magnetostrictive self-calibration device comprises a control and display platform, a data acquisition platform and a test platform.

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