A method for calibrating a magnetic field strength measuring coil based on a pulsed strong magnetic field

Abstract

The application provides a magnetic field strength measurement coil calibration method based on a pulse strong magnetic field, adopts a pulse strong magnetic field to replace a sinusoidal wave magnetic field, completes calibration of a magnetic field strength measurement coil constant, and solves a traceability problem of a square centimeter level coil. The method comprises the following steps: step one, calculating an initial value of a pulse magnetic field parameter according to the magnetic field strength measurement coil; step two, placing the magnetic field strength measurement coil into a pulse magnetic field generation area, making a measurement axis of the magnetic field strength measurement coil consistent with a direction of a reproduced magnetic field, adjusting a pulse magnetic field reproduction device to output a pulse magnetic field parameter, and recording a peak magnetic induction intensity and a pulse width of the pulse magnetic field reproduction device; step three, measuring an output voltage of the magnetic field strength measurement coil in the pulse width by using a fluxmeter, adjusting to a set magnetic flux range, and recording a peak value; and step four, calculating the magnetic field strength measurement coil constant according to the peak magnetic induction intensity obtained in step two and the peak value obtained in step three.

Description

Technical Field

[0001] This invention belongs to the field of magnetic metrology technology and relates to a method for calibrating a magnetic field strength measurement coil based on a pulsed strong magnetic field. Background Technology

[0002] Magnetic field strength measuring coils, also known as H coils, are commonly used to measure the magnetization field strength during the measurement of magnetic materials. The accuracy of the magnetization field measurement determines the accuracy of the determination of magnetization field-related curves such as the BH curve and μ-H curve in the measurement of magnetic materials.

[0003] Existing methods for measuring the coil constant of a magnetic field strength measurement coil involve exciting the coil with a sinusoidal magnetic field, measuring the output of its induced voltage, and then using the formula... Calculate the magnetic field strength measuring coil constant. .

[0004] However, this method achieves high accuracy (up to 0.05%) when measuring coils with large constants (on the order of square meters) due to the high output of U. But when measuring magnetic field strength on the order of square centimeters, due to current engineering limitations, the sinusoidal magnetic field reproduction capability cannot simultaneously achieve high-frequency, strong magnetic fields. The magnetic field strength cannot be enhanced simultaneously, therefore the induced output voltage of the measuring coil is on the order of square centimeters. Typically, at the microvolt level, the measurement accuracy level drops significantly, usually reaching only below 10% or even lower, making it difficult to meet the traceability requirements of the magnetic field strength measurement coil used in the measurement of magnetic materials. Summary of the Invention

[0005] Based on this, the present invention proposes a calibration method for a magnetic field strength measurement coil based on a pulsed strong magnetic field. The method replaces the sinusoidal magnetic field with a pulsed strong magnetic field to complete the calibration of the magnetic field strength measurement coil constant, thus solving the traceability problem of coils on the order of square centimeters.

[0006] The present invention is achieved through the following technical solution.

[0007] A method for calibrating a magnetic field strength measurement coil based on a pulsed strong magnetic field includes the following steps: Step 1: Calculate the initial parameters of the pulsed magnetic field based on the magnetic field strength measuring coil; specifically: Step 2: Place the magnetic field strength measuring coil into the pulse magnetic field generating area, ensuring that the measuring axis of the magnetic field strength measuring coil is aligned with the direction of the reproduced magnetic field. Adjust the pulse magnetic field reproduction device and output the pulse magnetic field parameters. Record the peak magnetic induction intensity of the pulse magnetic field reproduction device and pulse width ; Step 3: Use a fluxmeter to measure the magnetic field strength within the pulse width. Adjust the coil output voltage to the set flux range and record the peak value. ; Step 4: Based on the peak magnetic induction intensity obtained in Step 2 And the peak value obtained in step three Calculate the constant of the magnetic field strength measuring coil The specific formula is as follows: (3) This enabled the calibration of the magnetic field strength measurement coil constant.

[0008] The beneficial effects of this invention are: 1. Compared with existing technologies, this invention can complete the calibration of the coil constant for measuring magnetic field strength at the square centimeter level with a measurement uncertainty level of 0.5% to 1%, and has the effect of high measurement accuracy; 2. This invention employs pulsed high magnetic field calibration technology, which can provide higher precision calibration results. By applying a high-intensity magnetic field in a short time, the coil constant of the magnetic field strength measuring coil (hereinafter referred to as the H coil) can be determined more accurately. In particular, for the H coil with a square centimeter range, a measurement uncertainty level of 0.5% to 1% can be achieved, which was previously difficult to achieve. 3. This invention is applicable to H-coils of various sizes and types, including H-coils of various sizes and induction directions for laboratory equipment, industrial equipment, and scientific research. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the magnetic field strength measurement coil calibration method based on pulsed strong magnetic field of the present invention; Figure 2 This is an example diagram of a pulsed magnetic field waveform in a specific embodiment of the present invention. Detailed Implementation

[0010] Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the embodiments shown and described in the drawings are merely exemplary and are intended to illustrate the principles and spirit of the present invention, and are not intended to limit the scope of the present invention.

[0011] like Figure 1 As shown, the present invention provides a method for calibrating a magnetic field strength measuring coil based on a pulsed strong magnetic field, which specifically includes the following steps: Step 1: Calculate the initial parameters of the pulsed magnetic field based on the magnetic field strength measuring coil; specifically: The winding diameter of the coil is measured based on the magnetic field strength. and number of wire turns The target value of the turn area is initially calculated using formula (1). ; (1) Based on the target value and the optimal output voltage (1 V to 5 V), the pulse magnetic field parameters are calculated using formula (2). The unit is T / s; (2) Step 2: Place the magnetic field strength measuring coil into the pulse magnetic field generating area, ensuring that the measuring axis of the magnetic field strength measuring coil is aligned with the direction of the reproduced magnetic field. Adjust the pulse magnetic field reproduction device and output the pulse magnetic field parameters. Record the peak magnetic induction intensity of the pulse magnetic field reproduction device and pulse width In this embodiment, the pulsed magnetic field generating region is selected from the near-end face of the pulsed magnet; In practice, the pulse width is controlled between 1ms and 10ms. This is because a pulse magnetic field with a pulse width of less than 10ms is theoretically possible, but it is easily affected by ambient magnetic field noise. The peak value of the pulse magnetic field is controlled between 1T and 10T. The magnetic field waveform is a single pulse waveform, specifically a 20 / 80 waveform or a quasi-half sine wave. The pulse width is the duration of the waveform, and the calculation range is from the beginning of the waveform change to the waveform returning to its initial state.

[0012] Step 3: Use a fluxmeter to measure the magnetic field strength within the pulse width. Adjust the coil output voltage to the set flux range and record the peak value. ; In this embodiment, the set magnetic flux range is 10 mWb.

[0013] In specific implementation, the peak value The deviation from the initial state may be positive or negative, and the positive or negative deviation is only related to the winding direction of the magnetic moment coil.

[0014] Step 4: Based on the peak magnetic induction intensity obtained in Step 2 And the peak value obtained in step three Calculate the constant of the magnetic field strength measuring coil The specific formula is as follows: (3) This enabled the calibration of the magnetic field strength measurement coil constant.

[0015] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0016] It will be apparent to those skilled in the art that the embodiments of the present invention are not limited to the details of the exemplary embodiments described above, and that the embodiments of the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the embodiments of the present invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the embodiments of the present invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be encompassed within the embodiments of the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units, modules, or devices recited in the system, apparatus, or terminal claims may also be implemented by the same unit, module, or device through software or hardware. The terms "first," "second," etc., are used to indicate names and do not indicate any particular order.

[0017] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention and are not intended to limit them. Although the embodiments of the present invention have been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the embodiments of the present invention should not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of calibrating a magnetic field strength measuring coil based on a pulsed strong magnetic field, characterized by, Includes the following steps: Step 1: Calculate the initial parameters of the pulsed magnetic field based on the magnetic field strength measuring coil; The initial parameters of the pulsed magnetic field are calculated as follows: According to the winding diameter of the magnetic field intensity measuring coil and the number of wire turns , the target value of the turn area is calculated preliminarily by formula (1) ; wherein the diameter is in cm, and the number of wire turns is in turns. （1） Based on the target value and the optimal output voltage U, the output voltage is taken as 1 V to 5 V. The pulse magnetic field parameters are calculated using formula (2). The unit is T / s; （2）； Step 2: Place the magnetic field strength measuring coil into the pulse magnetic field generating area, ensuring that the measuring axis of the magnetic field strength measuring coil is aligned with the direction of the reproduced magnetic field. Adjust the pulse magnetic field reproduction device and output the pulse magnetic field parameters. Record the peak magnetic induction intensity of the pulse magnetic field reproduction device and pulse width Pulse width The unit is s, and the pulse magnetic field generation region is selected from the near end face of the pulse magnet; Step 3: Use a fluxmeter to measure the magnetic field strength within the pulse width. Adjust the coil output voltage to the set flux range and record the peak value. The set magnetic flux range is 10 mWb. Step 4: Based on the peak magnetic induction intensity obtained in Step 2 And the peak value obtained in step three Calculate the constant of the magnetic field strength measuring coil Among them, peak magnetic induction intensity The unit is T, and the peak value is... The unit is , The unit is The specific formula is as follows: （3） This enabled the calibration of the magnetic field strength measurement coil constant.

2. The method for calibrating a magnetic field strength measurement coil based on a pulsed strong magnetic field as described in claim 1, characterized in that, The pulse width is controlled between 1ms and 10ms.

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