High-precision calibration method and device for roebel coil for pulsed large current source measurement

Abstract

The application discloses a high-precision calibration method of a Rogowski coil for pulse large-current source measurement, and steps are as follows: S1, a adjustable hundred-A-grade precision current test source is built; S2, a Rogowski coil scale factor calibration test system is built; S3, a Rogowski coil scale factor current amplitude is calibrated; S4, a Rogowski coil line scale factor frequency is calibrated; and S5, verification is conducted after the Rogowski coil line scale factor calibration. The application also discloses a device for realizing the high-precision calibration method of the Rogowski coil for pulse large-current source measurement. The application uses a precision small current source to replace a traditional large-power pulse current source as a calibration source, so that the test equipment requirement, test difficulty and test safety can be effectively reduced. The fine calibration method combining the Rogowski coil scale factor current amplitude calibration and the frequency calibration can effectively reduce the influence of amplitude and frequency changes on the measurement precision in pulse measurement. Compared with the traditional calibration, the Rogowski coil calibration precision can be significantly improved.

Description

Technical Field

[0001] This invention relates to the field of pulsed high current source measurement technology, specifically to a high-precision calibration method and equipment for Rogowski coils used in pulsed high current source measurement. Background Technology

[0002] High-power pulsed electric energy sources are a key component of electromagnetic launch equipment, characterized by high voltage (above kilovolts), high current (above kiloamperes), fast pulse speed (micro-nanoseconds), and high power (megawatt level). The amplitude, phase, and frequency characteristics of the pulse shaping network (PFN) current in a high-power pulsed electric energy source are indicators of its performance. Measuring these characteristics allows for simulation verification, optimization design, and accurate performance evaluation of the entire discharge circuit. However, accurately measuring the ultimate electrical performance of high-power pulsed electric energy sources remains a pressing challenge.

[0003] Furthermore, for the measurement of MW-level PFN discharge circuits, the most common method currently used is to employ a Rogowski coil as the front-end current sensor. This involves setting an integration method and using a high-precision acquisition device to collect the current signal, then using the calibration factor specified by the Rogowski coil before it leaves the factory to calculate the discharge circuit current. Although the amplitude range and measurement frequency of the Rogowski coil meet the requirements for PFN discharge circuit measurement, the measurement error caused by solving the current based on a fixed calibration factor is typically above 1%, which cannot meet practical testing requirements. Therefore, reducing the measurement error of the Rogowski coil is one of the key technologies for PFN discharge circuit measurement.

[0004] Furthermore, a traditional method to improve the measurement accuracy of Rogowski coils is to calibrate the coil's scale factor. This calibration typically involves connecting a coaxial shunt in series with the PFN discharge circuit, measuring the voltage across the shunt, and comparing it to the Rogowski coil's output to calibrate the actual scale factor. The calibrated scale factor better reflects the actual measurement conditions, thus improving the Rogowski coil's measurement accuracy to some extent. However, existing calibration methods have several drawbacks:

[0005] (1) The calibration accuracy is low. High-power pulsed electric energy requires a measurement accuracy of less than 5‰ for Rogowski coils, and this calibration method cannot meet the accuracy requirements.

[0006] (2) Poor applicability of the calibration factor under single-frequency conditions. In actual measurements, due to the inherent characteristics of the Rogowski coil and the combined influence of the conditioning circuit, the calibration factor of the Rogowski coil varies greatly under different frequency conditions. The calibration factor calibration method under fixed frequency conditions works well in 50Hz power frequency high-current testing applications, but it cannot meet the high-precision measurement requirements of PFN discharge circuits, which have a wide spectral component distribution. Therefore, how to reduce the influence of frequency on the calibration factor is another difficult problem to solve in PFN discharge circuit measurement.

[0007] Given the limited power pulse energy available for calibration (in MW levels) and the challenging installation process using a coaxial shunt series measurement method, which can pose risks to both personnel and equipment, improving the safety of Rogowski coils is a key focus in calibration. Summary of the Invention

[0008] The purpose of embodiments of the present invention is to provide a high-precision calibration method and device for Rogowski coils used for pulsed high-current source measurement, so as to solve the above-mentioned problems.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A high-precision calibration method for Rogowski coils used in pulsed high-current source measurements includes the following steps:

[0011] S1. Construct an adjustable 100A-level precision current test source:

[0012] A high-power precision current source is constructed using a signal generator and a precision power amplifier. A low-temperature drift precision resistor is used as the load resistor to build a precision current test source. The output channel of the signal generator is connected to the signal input interface of the precision power amplifier. The output terminal of the precision power amplifier is connected in parallel with the load resistor array. By adjusting the signal type and amplitude of the signal generator and the scaling factor of the precision power amplifier, the signal type, amplitude characteristics, and frequency characteristics of the current flowing through the load current are changed, providing a test source for the linearity and frequency calibration of the Rogowski coil. A multi-turn coil is wound in the current loop and passed through the Rogowski coil, increasing the maximum primary current flowing through the Rogowski coil to 500A. The induced current in the Rogowski coil is as follows:

[0013]

[0014] Among them, I 总 V is the total primary current flowing through the Rogowski coil; N is the number of turns in the coil; V is the voltage across the load resistor; R is the load resistance.

[0015] The output amplitude can be obtained based on the factory calibration factor K:

[0016]

[0017] S2. Establish a Rogowski coil scale factor calibration test system:

[0018] The calibration and testing system includes the Rogowski coil under test, a 100A-level precision current test source, a functional digital multimeter, a high-precision data acquisition card, a host computer, and a data acquisition and analysis software module. The multimeter probes are placed across the load resistor to measure the voltage and resistance across the load resistor, thus obtaining the current flowing through it. The actual current flowing through the Rogowski coil can be calculated based on the number of turns. The high-precision data acquisition card, host computer, and data acquisition and analysis software module constitute the Rogowski coil output voltage test unit, which acquires the output voltage amplitude in real time. The voltage is calculated using the scale factor formula: K = I. in / V out The scale factor value can be calculated; where I in V is the primary current. out This refers to the output voltage of the Rogowski coil.

[0019] S3, Rogowski coil scale factor current amplitude calibration:

[0020] Set the input waveform and frequency of the signal generator, adjust the primary-side input current by changing the power amplifier scaling factor, and measure multiple sets of load voltage, load resistance, and Rogowski coil output voltage under different scaling factor conditions using a calibration test system, and calculate the average value; where the average load voltage is... The average load resistance is The average output voltage of the Rogowski coil is

[0021] According to the primary current calculation formula The average value of the actual primary current under different amplification factors can be obtained: According to K=I in / V out The average scale factor under different current conditions can be calculated:

[0022]

[0023] For the measured as well as Linear fitting was performed to obtain the relationship between the scale factor and the change in current amplitude: The linearity δ of the fitted line is calculated. If δ is within 3‰, it indicates that the change in current amplitude has little impact on the scale factor. The method of extrapolating the scale factor under large current conditions using a small current source is feasible.

[0024] S4. Rogowski coil line scale factor frequency calibration:

[0025] Using a sine wave as the signal input, with the amplifier gain set to a fixed value, the sine wave input frequency is changed at equal intervals, and the average value of the calibration factor under different frequency conditions is measured using a method similar to that in S3; simultaneously, according to and the corresponding f = [f1, f2, f3, ... f n Curve fitting was performed to obtain the relationship between the scale factor and the change in current frequency:

[0026]

[0027] Verification after S5 and Rogowski coil line scale factor calibration:

[0028] By randomly changing the input frequency of the sine wave and measuring the actual current value I flowing through the Rogowski coil. 总i and the voltage value output by the Rogowski coil. The theoretical scale factor K is solved by substituting the frequency of the input signal into the frequency fitting curve. i =F(f i The measured current value is And calculate the relative error γ:

[0029]

[0030] If the measurement error of a Rogowski coil with a nominal accuracy of 1% under different frequency conditions is better than 5‰ after calibration, then the calibration requirement is met.

[0031] In one alternative: In step S1, to ensure that the current and voltage flowing through the load resistor are within the rated range, the low-temperature drift precision resistor is made of 25 high-power 60Ω aluminum-cased resistors connected in parallel, controlling the total resistance value to 3Ω and the maximum allowable current to flow through to 15A; the aluminum-cased resistors themselves have heat dissipation function, and at the same time, the parallel aluminum-cased resistors are placed on a large-scale heat dissipation copper plate to avoid the resistor temperature from being too high.

[0032] In one alternative: In step S2, the functional digital multimeter is an 8.5-digit high-precision digital multimeter; the high-precision data acquisition card is a 16-bit data acquisition card, used to reduce the error of the measuring instrument and ensure the accuracy of measuring the average voltage and load resistance of the sine wave.

[0033] In one alternative: In step S2, the host computer measurement software has waveform display, waveform spectrum analysis, amplitude measurement and rise time measurement functions. When measuring a sine wave, the measured voltage peak value is converted into the voltage effective value for calibration factor calculation.

[0034] In one alternative scheme: In step S3, the current amplitude varies between 50A and 500A, and the input signal frequency of the signal source is 100Hz; if the linearity δ of the function between the measured amplitude and the scale factor is better than 3‰, then the average value of the scale factor of the current amplitude variation under each frequency condition is calculated and used as a fixed scale factor; if the linearity is poor, then the influence of the amplitude variation on the scale factor is fitted into a curve, and the frequency calibration curve in S4 is corrected for error.

[0035] In one alternative approach: In step S4, based on the measurement characteristics of the Rogowski coil, the frequency variation range during the frequency calibration process is 100Hz to 10KHz, with equal intervals of 50Hz; to improve calibration accuracy, the average of the measured calibration data is calculated in 50 sets.

[0036] In one alternative approach: In steps S3 and S4, the effect of the current amplitude change on the calibration factor can be used as a fixed error correction factor to correct the frequency model, and the correction method is as follows:

[0037] (3) Set the amplitude correction factor to Kv and fix the amplitude I. f The function under the condition is The corresponding error correction function is

[0038] (4) Kv is calculated as follows:

[0039] ①If The linearity δ < 3‰, Kv = 1;

[0040] ②If The linearity δ>3‰,

[0041] In one alternative approach, the specific calibration process is as follows:

[0042] ① Build a Rogowski coil scale factor calibration test system and use an oscilloscope to test whether the output signal is distorted;

[0043] ② Set the frequency of the signal source and the amplification factor of the precision amplifier;

[0044] ③ The test system was kept stable for 30 minutes to ensure that the load resistance value remained stable.

[0045] ④ Measure the load voltage multiple times using a multi-function digital multimeter, and collect the Rogowski coil output voltage multiple times using LabVIEW software.

[0046] ⑤ After a single test is completed, disconnect the power and measure the load resistance value;

[0047] ⑥ Use the same measurement steps to facilitate all amplitude and frequency values;

[0048] ⑦ Fit the amplitude variation curve and frequency curve, and verify the accuracy after calibration;

[0049] ⑧ The calibration test ends when the accuracy meets the requirements after calibration.

[0050] A high-precision calibration device for Rogowski coils used in pulsed high-current source measurements includes:

[0051] Memory, used to store programs;

[0052] The processor, when executing the program stored in the memory, implements the steps of the above-described high-precision calibration method for Rogowski coils used for pulsed high-current source measurement.

[0053] A storage medium storing a computer program, the computer program being executed by a processor to implement the steps of the above-described high-precision calibration method for Rogowski coils for pulsed high-current source measurement.

[0054] Compared with the prior art, the beneficial effects of the embodiments of the present invention are as follows:

[0055] Replacing the traditional high-power pulse current source with a precision low-current source as the calibration source can effectively reduce the requirements for test equipment, test difficulty, and test safety. At the same time, the refined calibration method that combines Rogowski coil scale factor current amplitude calibration and frequency calibration can effectively reduce the impact of amplitude and frequency changes on measurement accuracy in pulse measurement. Compared with traditional calibration, it can significantly improve the calibration accuracy of Rogowski coil. Attached Figure Description

[0056] Figure 1 This is a flowchart of a high-precision calibration method for Rogowski coils used for pulsed high-current source measurement according to the first embodiment of the present invention;

[0057] Figure 2 yes Figure 1 The structural diagram of the Rogowski coil scale factor calibration test system built in step S2;

[0058] Figure 3 It is a flowchart of the calibration process.

[0059] In the diagram, 101-signal generator, 102-precision power amplifier, 103-load resistor, 201-Rogowski coil under test, 202-functional digital multimeter, 203-high-precision data acquisition card, 204-host computer, 205-acquisition and analysis software module. Detailed Implementation

[0060] The following embodiments will describe the present invention in detail with reference to the accompanying drawings. In the drawings and description, similar or identical parts are referred to by the same reference numerals. The embodiments listed in this invention are only for illustration and are not intended to limit the scope of the invention. Any obvious modifications or changes made to this invention do not depart from the spirit and scope of the invention.

[0061] Example 1

[0062] Please see Figures 1-3 In this embodiment of the invention, a high-precision calibration method for a Rogowski coil used for pulsed high-current source measurement includes the following steps:

[0063] S1. Construct an adjustable 100A-level precision current test source:

[0064] A high-power precision current source is constructed using a signal generator and a precision power amplifier. A low-temperature drift precision resistor is used as the load resistor to build a precision current test source. The output channel of the signal generator is connected to the signal input interface of the precision power amplifier. The output terminal of the precision power amplifier is connected in parallel with the load resistor array. By adjusting the signal type and amplitude of the signal generator and the scaling factor of the precision power amplifier, the signal type, amplitude characteristics, and frequency characteristics of the current flowing through the load current are changed, providing a test source for the linearity and frequency calibration of the Rogowski coil. A multi-turn coil 104 is wound in the current loop and passed through the Rogowski coil, increasing the maximum primary current flowing through the Rogowski coil to 500A. The induced current in the Rogowski coil is as follows:

[0065]

[0066] Among them, I 总 V is the total primary current flowing through the Rogowski coil; N is the number of turns in the coil; V is the voltage across the load resistor; R is the load resistance.

[0067] The output amplitude can be obtained based on the factory calibration factor K:

[0068]

[0069] S2. Establish a Rogowski coil scale factor calibration test system:

[0070] The calibration and testing system includes the Rogowski coil under test, a 100A-level precision current test source, a functional digital multimeter, a high-precision data acquisition card, a host computer, and a data acquisition and analysis software module. The multimeter probes are placed across the load resistor to measure the voltage and resistance across the load resistor, thus obtaining the current flowing through it. The actual current flowing through the Rogowski coil can be calculated based on the number of turns. The high-precision data acquisition card, host computer, and data acquisition and analysis software module constitute the Rogowski coil output voltage test unit, which acquires the output voltage amplitude in real time. The voltage is calculated using the scale factor formula: K = I. in / V out The scale factor value can be calculated, where I in V is the primary current. out This refers to the output voltage of the Rogowski coil.

[0071] S3, Rogowski coil scale factor current amplitude calibration:

[0072] Set the input waveform and frequency of the signal generator, adjust the primary-side input current by changing the power amplifier scaling factor, and measure multiple sets of load voltage, load resistance, and Rogowski coil output voltage under different scaling factor conditions using a calibration test system, and calculate the average value; where the average load voltage is... The average load resistance is The average output voltage of the Rogowski coil is

[0073] According to the primary current calculation formula The average value of the actual primary current under different amplification factors can be obtained: According to K=I in / V out The average scale factor under different current conditions can be calculated:

[0074]

[0075] For the measured as well as Linear fitting was performed to obtain the relationship between the scale factor and the change in current amplitude: The linearity δ of the fitted line is calculated. If δ is within 3‰, it indicates that the change in current amplitude has little impact on the scale factor. The method of extrapolating the scale factor under large current conditions using a small current source is feasible.

[0076] S4. Rogowski coil line scale factor frequency calibration:

[0077] Using a sine wave as the signal input, with the amplifier gain set to a fixed value, the sine wave input frequency is changed at equal intervals, and the average value of the calibration factor under different frequency conditions is measured using a method similar to that in S3; simultaneously, according to and the corresponding f = [f1, f2, f3, ... f n Curve fitting was performed to obtain the relationship between the scale factor and the change in current frequency:

[0078]

[0079] Verification after S5 and Rogowski coil line scale factor calibration:

[0080] By randomly changing the input frequency of the sine wave and measuring the actual current value I flowing through the Rogowski coil. 总i and the voltage value output by the Rogowski coil. The theoretical scale factor K is solved by substituting the frequency of the input signal into the frequency fitting curve. i =F(f i The measured current value is And calculate the relative error γ:

[0081]

[0082] If the measurement error of a Rogowski coil with a nominal accuracy of 1% under different frequency conditions is better than 5‰ after calibration, then the calibration requirement is met.

[0083] In step S1, to ensure that the current and voltage flowing through the load resistor are within the rated range, the low-temperature drift precision resistor uses 25 high-power 60Ω aluminum-cased resistors connected in parallel to control the total resistance value at 3Ω and the maximum allowable current is 15A. The aluminum-cased resistors themselves have a heat dissipation function, and the parallel aluminum-cased resistors are placed on a large-scale heat dissipation copper plate to avoid the resistor temperature from being too high.

[0084] In step S2, the functional digital multimeter is an 8.5-digit high-precision digital multimeter; the high-precision data acquisition card is a 16-bit data acquisition card, used to reduce the error of the measuring instrument and ensure the accuracy of measuring the average voltage and load resistance of the sine wave.

[0085] In step S2, the host computer measurement software has waveform display, waveform spectrum analysis, amplitude measurement and rise time measurement functions. During sine wave measurement, the measured voltage peak value is converted into the voltage effective value for calibration factor calculation.

[0086] In step S3, the current amplitude varies between 50A and 500A, and the input signal frequency of the signal source is 100Hz. If the linearity δ of the function between the measured amplitude and the scale factor is better than 3‰, the average value of the scale factor of the current amplitude variation under each frequency condition is calculated and used as a fixed scale factor. If the linearity is poor, the influence of the amplitude variation on the scale factor is fitted into a curve, and the frequency calibration curve in S4 is corrected for error.

[0087] In step S4, based on the measurement characteristics of the Rogowski coil, the frequency variation range during the frequency calibration process is 100Hz to 10KHz, with an equal interval of 50Hz; to improve calibration accuracy, the average of the measured calibration data is calculated in 50 sets.

[0088] In steps S3 and S4, the effect of current amplitude change on the calibration factor can be used as a fixed error correction factor to correct the frequency model. The correction method is as follows:

[0089] (5) Set the amplitude correction factor to Kv and fix the amplitude I. f The function under the condition is The corresponding error correction function is

[0090] (6) Kv is calculated as follows:

[0091] ①If The linearity δ < 3‰, Kv = 1;

[0092] ②If The linearity δ>3‰,

[0093] The specific calibration process is as follows:

[0094] ① Build a Rogowski coil scale factor calibration test system and use an oscilloscope to test whether the output signal is distorted;

[0095] ② Set the frequency of the signal source and the amplification factor of the precision amplifier;

[0096] ③ The test system was kept stable for 30 minutes to ensure that the load resistance value remained stable.

[0097] ④ Measure the load voltage multiple times using a multi-function digital multimeter, and collect the Rogowski coil output voltage multiple times using LabVIEW software.

[0098] ⑤ After a single test is completed, disconnect the power and measure the load resistance value;

[0099] ⑥ Use the same measurement steps to facilitate all amplitude and frequency values;

[0100] ⑦ Fit the amplitude variation curve and frequency curve, and verify the accuracy after calibration;

[0101] ⑧ The calibration test ends when the accuracy meets the requirements after calibration.

[0102] Example 2

[0103] A high-precision calibration device for Rogowski coils used in pulsed high-current source measurements includes:

[0104] Memory, used to store programs;

[0105] The processor, when executing a program stored in the memory, implements the steps of the high-precision calibration method for Rogowski coils for pulsed high-current source measurement as described in Example 1.

[0106] Example 3

[0107] A storage medium storing a computer program, the computer program being executed by a processor to implement the steps of the high-precision calibration method for Rogowski coils for pulsed high-current source measurement as described in the embodiments.

[0108] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A high-precision calibration method for Rogowski coils used in pulsed high-current source measurements, characterized in that, The steps are as follows: S1. Construct an adjustable 100A-level precision current test source: A high-power precision current source is constructed using a signal generator and a precision power amplifier. A low-temperature drift precision resistor is used as the load resistor to build a precision current test source. The output channel of the signal generator is connected to the signal input interface of the precision power amplifier. The output terminal of the precision power amplifier is connected in parallel with the load resistor array. By adjusting the signal type and amplitude of the signal generator and the scaling factor of the precision power amplifier, the signal type, amplitude characteristics, and frequency characteristics of the current flowing through the load current are changed, providing a test source for the linearity and frequency calibration of the Rogowski coil. A multi-turn coil is wound in the current loop and passed through the Rogowski coil, increasing the maximum primary current flowing through the Rogowski coil to 500A. The induced current in the Rogowski coil is as follows: Among them, I 总 V is the total primary current flowing through the Rogowski coil; N is the number of turns in the coil; V is the voltage across the load resistor; R is the load resistance. The output amplitude can be obtained based on the factory calibration factor K: S2. Establish a Rogowski coil scale factor calibration test system: The calibration and testing system includes the Rogowski coil under test, a 100A-level precision current test source, a functional digital multimeter, a high-precision data acquisition card, a host computer, and a data acquisition and analysis software module. The multimeter probes are placed across the load resistor to measure the voltage and resistance across the load resistor, thus obtaining the current flowing through it. The actual current flowing through the Rogowski coil can be calculated based on the number of turns. The high-precision data acquisition card, host computer, and data acquisition and analysis software module constitute the Rogowski coil output voltage test unit, which acquires the output voltage amplitude in real time. The voltage is calculated using the scale factor formula: K = I. in / V out The scale factor value can be calculated; where I in V is the primary current. out This refers to the output voltage of the Rogowski coil. S3, Rogowski coil scale factor current amplitude calibration: Set the input waveform and frequency of the signal generator, adjust the primary-side input current by changing the power amplifier scaling factor, and measure multiple sets of load voltage, load resistance, and Rogowski coil output voltage under different scaling factor conditions using a calibration test system, and calculate the average value; where the average load voltage is... The average load resistance is The average output voltage of the Rogowski coil is According to the primary current calculation formula The average value of the actual primary current under different amplification factors can be obtained: According to K=I in / Vo ut The average scale factor under different current conditions can be calculated: For the measured as well as Linear fitting was performed to obtain the relationship between the scale factor and the change in current amplitude: The linearity δ of the fitted line is calculated. If δ is within 3‰, it indicates that the change in current amplitude has little impact on the scale factor. The method of extrapolating the scale factor under large current conditions using a small current source is feasible. S4. Rogowski coil line scale factor frequency calibration: Using a sine wave as the signal input, with the amplifier gain set to a fixed value, the sine wave input frequency is changed at equal intervals, and the average value of the calibration factor under different frequency conditions is measured using a method similar to that in S3; simultaneously, according to and the corresponding f = [f1, f2, f3, ... f n Curve fitting was performed to obtain the relationship between the scale factor and the change in current frequency: Verification after S5 and Rogowski coil line scale factor calibration: By randomly changing the input frequency of the sine wave and measuring the actual current value I flowing through the Rogowski coil. 总i and the voltage value output by the Rogowski coil The theoretical scale factor K is solved by substituting the frequency of the input signal into the frequency fitting curve. i =F(f i The measured current value is And calculate the relative error γ: If the measurement error of a Rogowski coil with a nominal accuracy of 1% under different frequency conditions is better than 5‰ after calibration, then the calibration requirement is met.

2. The high-precision calibration method for Rogowski coils used in pulsed high-current source measurement according to claim 1, characterized in that, In step S1, to ensure that the current and voltage flowing through the load resistor are within the rated range, the low-temperature drift precision resistor uses 25 high-power 60Ω aluminum-cased resistors connected in parallel to control the total resistance value at 3Ω and the maximum allowable current is 15A. The aluminum-cased resistors themselves have heat dissipation function, and the parallel aluminum-cased resistors are placed on a large-scale heat sink copper plate to avoid the resistor temperature from getting too high.

3. The high-precision calibration method for Rogowski coils used in pulsed high-current source measurement according to claim 1, characterized in that, In step S2, the functional digital multimeter is an 8.5-digit high-precision digital multimeter; the high-precision data acquisition card is a 16-bit data acquisition card, used to reduce the error of the measuring instrument and ensure the accuracy of measuring the average voltage and load resistance of the sine wave.

4. The high-precision calibration method for Rogowski coils used in pulsed high-current source measurement according to claim 1, characterized in that, In step S2, the host computer measurement software has waveform display, waveform spectrum analysis, amplitude measurement and rise time measurement functions. During sine wave measurement, the measured voltage peak value is converted into the voltage effective value for calibration factor calculation.

5. The high-precision calibration method for Rogowski coils used in pulsed high-current source measurement according to claim 1, characterized in that, In step S3, the current amplitude varies between 50A and 500A, and the input signal frequency of the signal source is 100Hz. If the linearity δ of the function between the measured amplitude and the scale factor is better than 3‰, the average value of the scale factor of the current amplitude variation under each frequency condition is calculated and used as a fixed scale factor. If the linearity is poor, the influence of the amplitude variation on the scale factor is fitted into a curve, and the frequency calibration curve in S4 is corrected for error.

6. The high-precision calibration method for Rogowski coils used in pulsed high-current source measurement according to claim 1, characterized in that, In step S4, based on the measurement characteristics of the Rogowski coil, the frequency variation range during the frequency calibration process is 100Hz to 10KHz, with an equal interval of 50Hz; to improve calibration accuracy, the average of the measured calibration data is calculated in 50 sets.

7. The high-precision calibration method for Rogowski coils used in pulsed high-current source measurement according to claim 1, characterized in that, In steps S3 and S4, the effect of current amplitude change on the calibration factor can be used as a fixed error correction factor to correct the frequency model. The correction method is as follows: (1) Set the amplitude correction factor to Kv and fix the amplitude I. f The function under the condition is The corresponding error correction function is (2) Kv is calculated as follows: ①If The linearity δ < 3‰, Kv = 1; ②If The linearity δ>3‰, 8. The high-precision calibration method for Rogowski coils used for pulsed high-current source measurement according to any one of claims 1-7, characterized in that, The specific calibration process is as follows: ① Build a Rogowski coil scale factor calibration test system and use an oscilloscope to test whether the output signal is distorted; ② Set the frequency of the signal source and the amplification factor of the precision amplifier; ③ The test system was kept stable for 30 minutes to ensure that the load resistance value remained stable. ④ Measure the load voltage multiple times using a multi-function digital multimeter, and collect the Rogowski coil output voltage multiple times using LabVIEW software. ⑤ After a single test is completed, disconnect the power and measure the load resistance value; ⑥ Use the same measurement steps to facilitate all amplitude and frequency values; ⑦ Fit the amplitude variation curve and frequency curve, and verify the accuracy after calibration; ⑧ The calibration test ends when the accuracy meets the requirements after calibration.

9. A high-precision calibration device for Rogowski coils used in pulsed high-current source measurement, characterized in that, include: Memory, used to store programs; The processor, when executing a program stored in memory, implements the steps of the high-precision calibration method for Rogowski coils for pulsed high-current source measurement as described in any one of claims 1-7.

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