阅读说明：本技术 雷电流峰值标定方法及装置 (Lightning current peak value calibration method and device ) 是由 麻志鹏 贾小迪 熊秀 康华 于 2021-05-18 设计创作，主要内容包括：本公开提供一种雷电流峰值标定方法及装置,涉及雷电测量技术领域,能够解决现有斜率法精度不高以及无法全量程覆盖的问题。具体技术方案为：通过计算雷电流记录卡磁条数据的包络数据,结合最小二乘拟合算法,利用雷电实验室冲击电流发生器产生的标准雷电冲击电流进行模拟试验来完成雷电流峰值标定的高精度标定方法。本发明用于雷电流峰值测量。(The invention provides a lightning current peak value calibration method and device, relates to the technical field of lightning measurement, and can solve the problems that the existing slope method is not high in precision and cannot cover the full range. The specific technical scheme is as follows: the high-precision calibration method for calibrating the lightning current peak value is completed by calculating the envelope data of the magnetic stripe data of the lightning current recording card and combining a least square fitting algorithm and carrying out a simulation test by using the standard lightning impulse current generated by the lightning laboratory impulse current generator. The method is used for measuring the peak value of the lightning current.)

1. A method for calibrating a lightning current peak value is characterized by comprising the following steps:

acquiring P lightning current recording cards which are not impacted by lightning and are in a full magnetic state;

respectively carrying out lightning impulse simulation experiments with different amplitudes on the P lightning current recording cards to obtain a lightning current peak value of each lightning current recording card and corresponding magnetic stripe data, and calculating envelope data of the magnetic stripe data of each lightning current recording card;

fitting to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording cards by adopting the lightning current peak values of the M lightning current recording cards and the envelope data of the corresponding magnetic stripe data;

and calibrating parameters in the initial fitting function by adopting lightning current peak values of N lightning current recording cards and envelope data of corresponding magnetic stripe data to obtain a target fitting function, wherein P is M + N.

2. The method of claim 1, wherein the P lightning current recording cards are respectively subjected to lightning impulse simulation experiments with different amplitudes, and obtaining the peak lightning current value of each lightning current recording card comprises:

acquiring an amplitude range of lightning impulse current, and dividing the amplitude range of the lightning impulse current according to a preset interval to obtain M sub-intervals;

carrying out lightning impulse simulation experiments with different amplitudes on M lightning current recording cards in the P lightning current recording cards according to the M sub-intervals, and determining the maximum value of the interval end points of the M sub-intervals as the lightning current peak value of each lightning current recording card;

dividing N lightning current recording cards in the P lightning current recording cards into two groups, respectively carrying out 8/20 mu s lightning impulse simulation test on each lightning current recording card in the first group, respectively carrying out 10/350 mu s lightning impulse simulation test on each lightning current recording card in the second group, and obtaining the lightning current peak value of each lightning current recording card in the N lightning current recording cards.

3. The method of claim 1, wherein the obtaining magnetic stripe data of each lightning current recording card comprises:

and acquiring the magnetic stripe data of each lightning current recording card through a lightning current recording card reader.

4. The method of claim 1, wherein the envelope data comprises an envelope area or an envelope length.

5. The method of claim 1, wherein said calculating envelope data for magnetic stripe data of each said lightning current recording card comprises:

when the envelope data is an envelope area, calculating the envelope data of the magnetic stripe data of each lightning current recording card by adopting a first formula, wherein the magnetic stripe data is a curved edge graph, and the envelope data is the area of the curved edge graph;

the first formula is:wherein S represents envelope data, n represents the number of divided sections of the curved edge pattern, Δ x represents a time unit of the divided section interval, and f (δ)_i) Is expressed at delta_iThe value of (c).

6. The method of claim 1, wherein the fitting of the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data to obtain the initial fitting function of the lightning current peak values and the envelope data comprises:

and fitting the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data by adopting a least square method and a filtering algorithm to obtain an initial fitting function of the lightning current peak values and the envelope data.

7. The method of claim 6, wherein the initial fitting function is a third order function.

8. The method of claim 2, wherein the calibrating the parameters in the initial fitting function by using the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data to obtain the target fitting function comprises:

calibrating parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the first group and the envelope data of the corresponding magnetic stripe data to obtain a first target fitting function;

and calibrating parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the second group and the envelope data of the corresponding magnetic stripe data to obtain a second target fitting function, wherein the parameters of the first target fitting function are different from the parameters of the second target fitting function.

9. A lightning current peak value calibration device is characterized by comprising:

the lightning current recording device comprises a first acquisition module, a second acquisition module and a control module, wherein the first acquisition module is used for acquiring P lightning current recording cards which are not in a full magnetic state under lightning impact;

the second acquisition module is used for respectively carrying out lightning impulse simulation experiments with different amplitudes on the P lightning current recording cards to acquire a lightning current peak value and corresponding magnetic stripe data of each lightning current recording card;

the calculation module is used for calculating envelope data of the magnetic stripe data of each lightning current recording card, and the envelope data comprise an envelope area or an envelope length;

the fitting module is used for fitting to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording cards by adopting the lightning current peak values of the M lightning current recording cards and the envelope data of the corresponding magnetic stripe data;

and the calibration module is used for calibrating the parameters in the initial fitting function by adopting the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data to obtain a target fitting function, wherein P is M + N.

Technical Field

The disclosure relates to the technical field of lightning measurement, in particular to a lightning current peak value calibration method and device.

Background

Thunder is a magnificent and somewhat daunting discharge phenomenon accompanied by flash and thunder, the voltage of the thunder can reach 1000 MV-10 MV, the current can reach 10 kA-300 kA, and the thunder has great destructive power, so that serious accidents such as human and animal casualties, building damage, explosion, fire, power failure of an electric power system, damage to electric equipment and the like are often caused. The measurement of lightning current amplitude is the basic work for carrying out lightning research, and has very important significance for researching lightning characteristics, analyzing lightning accidents and discussing lightning protection strategies.

The current recording card reader of the thunder current detects the algorithm principle of the thunder current peak value of the thunder current recording card is a slope method, namely, the magnitude of the thunder current peak value is determined by acquiring a magnetic field graph formed by magnetic stripe data and calculating the graph slope by taking two points at fixed positions. The algorithm detects relatively accurate values when the lightning current is lower than 80 kA. Because the lightning current peak value and the magnetic stripe information do not form a linear relation in the whole range of natural lightning, the card reader is not suitable for detecting large current, so that the conventional lightning current recording card reader has the advantages of low precision, small range, large volume and low intellectualization, and cannot cover a wide range of 0 kA-300 kA.

Disclosure of Invention

The embodiment of the disclosure provides a lightning current peak value calibration method and a lightning current peak value calibration device, which can solve the problems that the existing slope method is low in precision and cannot cover a full range. The technical scheme is as follows:

according to a first aspect of the embodiments of the present disclosure, there is provided a method for calibrating a peak value of a lightning current, the method including:

acquiring P lightning current recording cards which are not impacted by lightning and are in a full magnetic state;

respectively carrying out lightning impulse simulation experiments with different amplitudes on the P lightning current recording cards to obtain a lightning current peak value and corresponding magnetic stripe data of each lightning current recording card, and calculating envelope data of the magnetic stripe data of each lightning current recording card;

fitting to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording cards by adopting the lightning current peak values of the M lightning current recording cards and the envelope data of the corresponding magnetic stripe data;

and calibrating parameters in the initial fitting function by adopting the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data to obtain a target fitting function, wherein P is M + N.

In one embodiment, the performing the lightning impulse simulation experiment with different amplitudes on the P lightning current recording cards respectively comprises:

acquiring an amplitude range of the lightning impulse current, and dividing the amplitude range of the lightning impulse current according to a preset interval to obtain M sub-intervals;

carrying out lightning impulse simulation experiments with different amplitudes on M lightning current recording cards in the P lightning current recording cards according to M sub-intervals, and determining the maximum value of the interval end points of the M sub-intervals as the lightning current peak value of each lightning current recording card;

dividing N lightning current recording cards in the P lightning current recording cards into two groups, respectively carrying out 8/20 mu s lightning impulse simulation test on each lightning current recording card in the first group, respectively carrying out 10/350 mu s lightning impulse simulation test on each lightning current recording card in the second group, and obtaining the lightning current peak value of each lightning current recording card in the N lightning current recording cards.

In one embodiment, obtaining magnetic stripe data for each lightning current recording card comprises: and acquiring the magnetic stripe data of each lightning current recording card through a lightning current recording card reader.

In one embodiment, the envelope data comprises an envelope area or an envelope length.

In one embodiment, calculating envelope data for the magnetic stripe data of each lightning current recording card comprises:

when the envelope data is an envelope area, calculating the envelope data of the magnetic stripe data of each lightning current recording card by adopting a first formula, wherein the magnetic stripe data is a curved edge graph, and the envelope data is the area of the curved edge graph;

the first formula is:where S denotes envelope data, n denotes the number of divided sections for a curved edge pattern, Δ x denotes a time unit of the divided section interval, and f (δ)_i) Is expressed at delta_iThe value of (c).

In one embodiment, the method for obtaining the initial fitting function of the lightning current peak value and the envelope data by fitting by using the lightning current peak values of the M lightning current recording cards and the envelope data of the corresponding magnetic stripe data comprises the following steps:

and fitting the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data by adopting a least square method and a filtering algorithm to obtain an initial fitting function of the lightning current peak values and the envelope data.

In one embodiment, the initial fitting function is a third order function.

In one embodiment, calibrating parameters in the initial fitting function by using the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data, and obtaining the target fitting function includes:

calibrating parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the first group and the envelope data of the corresponding magnetic stripe data to obtain a first target fitting function;

and calibrating parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the second group and the envelope data of the corresponding magnetic stripe data to obtain a second target fitting function, wherein the parameters of the first target fitting function are different from the parameters of the second target fitting function.

According to a second aspect of the embodiments of the present disclosure, there is provided a lightning current peak calibration apparatus, including:

the lightning current recording card acquisition module is used for acquiring P lightning current recording cards which are not impacted by lightning and are in a full magnetic state;

the second acquisition module is used for respectively carrying out lightning impulse simulation experiments with different amplitudes on the P lightning current recording cards to acquire a lightning current peak value and corresponding magnetic stripe data of each lightning current recording card;

the calculating module is used for calculating envelope data of magnetic stripe data of each lightning current recording card, and the envelope data comprise an envelope area or an envelope length;

the fitting module is used for fitting to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording cards by adopting the lightning current peak values of the M lightning current recording cards and the envelope data of the corresponding magnetic stripe data;

and the calibration module is used for calibrating the parameters in the initial fitting function by adopting the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data to obtain a target fitting function, wherein P is M + N.

In one embodiment, the second obtaining module is configured to obtain an amplitude range of the lightning impulse current, and divide the amplitude range of the lightning impulse current according to a preset interval to obtain M sub-intervals; carrying out lightning impulse simulation experiments with different amplitudes on M lightning current recording cards in the P lightning current recording cards according to M sub-intervals, and determining the maximum value of the interval end points of the M sub-intervals as the lightning current peak value of each lightning current recording card; dividing N lightning current recording cards in the P lightning current recording cards into two groups, respectively carrying out 8/20 mu s lightning impulse simulation test on each lightning current recording card in the first group, respectively carrying out 10/350 mu s lightning impulse simulation test on each lightning current recording card in the second group, and obtaining the lightning current peak value of each lightning current recording card in the N lightning current recording cards.

In one embodiment, the second acquiring module is configured to acquire magnetic stripe data of each lightning current recording card through a lightning current recording card reader.

In one embodiment, the calculating module is configured to calculate, when the envelope data is an envelope area, envelope data of magnetic stripe data of each lightning current recording card by using a first formula, where the magnetic stripe data is a curved edge pattern, and the envelope data is an area of the curved edge pattern;

the first formula is:where S denotes envelope data, n denotes the number of divided sections for a curved edge pattern, Δ x denotes a time unit of the divided section interval, and f (δ)_i) Is expressed at delta_iThe value of (c).

In one embodiment, the fitting module is configured to fit the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data by using a least square method and a filtering algorithm, so as to obtain an initial fitting function of the lightning current peak values and the envelope data.

In one embodiment, the initial fitting function is a third order function.

In one embodiment, the calibration module is configured to calibrate parameters in the initial fitting function by using a lightning current peak value of each lightning current recording card in the first group and envelope data of corresponding magnetic stripe data to obtain a first target fitting function;

and the calibration module is used for calibrating the parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the second group and the envelope data of the corresponding magnetic stripe data to obtain a second target fitting function, and the parameters of the first target fitting function are different from the parameters of the second target fitting function.

According to a third aspect of embodiments of the present disclosure, there is provided a lightning current peak calibration apparatus, which includes a processor and a memory, where at least one computer instruction is stored in the memory, and the instruction is loaded and executed by the processor to implement the steps performed in the lightning current peak calibration method described in the first aspect and any embodiment of the first aspect.

According to a fourth aspect of the embodiments of the present disclosure, there is provided a computer-readable storage medium having at least one computer instruction stored therein, where the at least one computer instruction is loaded and executed by a processor to implement the steps performed in the lightning current peak calibration method described in the first aspect and any embodiment of the first aspect.

The high-precision calibration method for calibrating the lightning current peak value is completed by calculating the envelope data of the magnetic stripe data of the lightning current recording card and combining a least square fitting algorithm and performing a simulation test by using 8/20 mu s and 10/350 mu s standard lightning impulse currents generated by an impulse current generator of a lightning laboratory. By calculating the envelope data of the magnetic stripe data, the amplitude detection range of the lightning current recording card is enlarged, and 0-300 kA full-range detection is realized. Meanwhile, the precision of the full range is improved to be less than or equal to +/-10 kA by using least square fitting and filtering algorithm and laboratory standard data calibration. And the accuracy and the reliability of reading the amplitude of the lightning current recording card are improved, and accurate and effective lightning stroke data are provided for customers.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

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

Fig. 1 is a flowchart of a method for calibrating a lightning current peak according to an embodiment of the disclosure;

fig. 2 is a flowchart of a method for calibrating a lightning current peak according to an embodiment of the disclosure;

FIG. 3 is a magnetic stripe data pattern of a 50kA thunder current recording card provided by an embodiment of the present disclosure;

fig. 4 is a structural diagram of a lightning current peak calibration apparatus according to an embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The embodiment of the present disclosure provides a method for calibrating a lightning current peak, as shown in fig. 1, the method for calibrating a lightning current peak includes the following steps:

101. and acquiring P lightning current recording cards.

The P lightning current recording cards are in a full magnetic state without being impacted by lightning. In the embodiment of the present disclosure, the magnetic stripe type lightning current recording card is adopted as the lightning current recording card, and the main principle of the magnetic stripe type lightning current recording card for recording the magnitude of the lightning current is the remanence method. Specifically, when a current flows through the conductor, a strong magnetic field is generated around the conductor, magnetic particles in the magnetic field are arranged in the direction of magnetic lines, the arrangement direction of the magnetic particles is inconsistent after the external magnetic field disappears, and the magnetic strip forms self magnetism, namely, a so-called remanence method.

102. And respectively carrying out lightning impulse simulation experiments with different amplitudes on the P lightning current recording cards to obtain the lightning current peak value of each lightning current recording card and corresponding magnetic stripe data, and calculating the envelope data of the magnetic stripe data of each lightning current recording card.

In the embodiment of the disclosure, the lightning impulse simulation experiments of different amplitudes performed on the P lightning current recording cards respectively refer to a lightning impulse simulation experiment corresponding to one lightning current recording card. Specifically, the lightning impulse simulation experiment that carries out different amplitudes respectively with P lightning current record card includes:

acquiring an amplitude range of the lightning impulse current, and dividing the amplitude range of the lightning impulse current according to a preset interval to obtain M sub-intervals;

carrying out lightning impulse simulation experiments with different amplitudes on M lightning current recording cards in the P lightning current recording cards according to M subintervals;

dividing N lightning current recording cards in the P lightning current recording cards into two groups, respectively carrying out 8/20 mu s lightning impulse simulation test on each lightning current recording card in the first group, respectively carrying out 10/350 mu s lightning impulse simulation test on each lightning current recording card in the second group, and obtaining the lightning current peak value of each lightning current recording card in the N lightning current recording cards.

The amplitude range of the lightning impulse current is the lightning impulse current in nature, the lightning impulse current in nature can reach 0-300 kA, the amplitude range of the lightning impulse current is divided according to preset intervals to obtain M sub-intervals, and illustratively, if the preset intervals are 10kA, the lightning impulse current is divided into 30 sub-intervals; if the preset interval is 20kA, dividing the preset interval into 15 sub-intervals; and then, performing lightning current surge simulation experiments with different amplitudes on M lightning current recording cards in the P lightning current recording cards according to M sub-intervals, namely one lightning current recording card corresponds to one sub-interval, meanwhile, dividing N lightning current recording cards in the P lightning current recording cards into two groups, performing a 8/20 mu s lightning current surge simulation experiment on each lightning current recording card in the first group, and performing a 10/350 mu s lightning current surge simulation experiment on each lightning current recording card in the second group to obtain a lightning current peak value of each lightning current recording card in the N lightning current recording cards. The number of the lightning current recording cards in the first group and the number of the lightning current recording cards in the second group can be the same or different; 8/20 mus and 10/350 mus are two different lightning stroke waveforms, 10/350 mus is the waveform used for direct lightning stroke test, 8/20 mus is the waveform used for indirect lightning stroke test. It should be noted that, in the lightning impulse simulation experiment, the standard lightning impulse current generated by the lightning through the impulse current generator is used for the simulation experiment.

And after lightning impulse simulation experiments are carried out on the lightning current recording cards, the lightning current peak value of each lightning current recording card and corresponding magnetic stripe data are obtained. For M lightning current recording cards, determining the maximum value of the interval end points of M sub-intervals as the lightning current peak value of each lightning current recording card, taking the preset interval as 10kA as an example, dividing the amplitude range of lightning impulse current from 0kA to 300kA into 30 sub-intervals, and then 30 lightning impulse recording cards are needed to carry out lightning impulse simulation experiments, wherein the lightning current peak values recorded by the 30 lightning current recording cards are respectively 10kA, 20kA, 30kA, … …, 290kA and 300 kA. And reading the magnetic stripe data of each lightning current recording card through a lightning current recording card reader, and calculating envelope data of the magnetic stripe data of each lightning current recording card, wherein the envelope data comprises an envelope area or an envelope length.

When the envelope data is an envelope area (i.e., a magnetic area), the envelope data for calculating the magnetic stripe data of each lightning current recording card includes: calculating the envelope data of the magnetic stripe data of each lightning current recording card by adopting a first formula, wherein the magnetic stripe data is a curved edge graph, and the envelope data is the area of the curved edge graph; wherein the first formula is:s represents envelope data, n represents the number of divided intervals for a curved edge pattern, Δ x represents a time unit of the divided interval intervals, and f (δ)_i) Is expressed at delta_iThe value of (c).

Of course, the envelope length of the magnetic stripe data of the lightning current recording card can also be calculated, and then the least square function of the envelope length and the lightning current peak value is fitted to detect the magnitude of the lightning current peak value. However, because the magnetic stripe data is an irregular pattern, compared with the envelope area, the envelope length is not easy to be accurately calculated, thereby influencing the precision of the lightning current peak value.

103. And (4) recording the possible lightning current peak values and the corresponding envelope data of the magnetic stripe data by adopting M lightning currents, and fitting to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording card.

In the embodiment of the disclosure, the least square method and the filtering algorithm are adopted to fit the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data, so as to obtain an initial fitting function of the lightning current peak values and the envelope data, wherein the initial fitting function is a third-order function. Specifically, the envelope data S is used as an argument, y is a lightning current peak value, and the fitting function y is f (S). Least squares polynomial curve fitting is the selection of the k-th order polynomial function that is most likely to produce given data, assuming that the data is generated by a k-th order polynomial function, i.e., the selection of a function among the k-th order polynomial functions that has good predictive power for known data as well as location data. Given a function y ═ f (S), at point S₁、S₂、S₃、……、S_kThe function values of (A) are respectively y₁、y₂、y₃、……、y_kSolving the polynomial of y ═ a₀+a₁S+a₂S²+……+a_kS^kSequentially selecting first-order, second-order, third-order and fourth-order function fitting, comparing fitting curve graphs, and optimally obtaining a third-order function, namely y is equal to a₀+a₁S+a₂S²+a₃S³，a₀、a₁、a₂And a₃Are fitting function parameters.

104. And calibrating parameters in the initial fitting function by adopting the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data to obtain a target fitting function.

After determining the post-fit function, the parameters in the fit function need to be calibrated as described in step 103, so the first group is combined with step 102Carrying out 8/20 mu s lightning impulse simulation test on each lightning current recording card respectively, recording the lightning current peak value of each lightning current recording card in the first group, and calculating envelope data corresponding to the magnetic stripe data of each lightning current recording card; and respectively carrying out 10/350 mu s lightning impulse simulation test on each lightning current recording card in the second group, recording the lightning current peak value of each lightning current recording card in the second group, and calculating envelope data corresponding to the magnetic stripe data of each lightning current recording card. Calibrating parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the first group and the envelope data of the corresponding magnetic stripe data to obtain a first target fitting function; and calibrating parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the second group and the envelope data of the corresponding magnetic stripe data to obtain a second target fitting function, wherein the parameters of the first target fitting function are different from the parameters of the second target fitting function. Illustratively, the data of each lightning current recording card in the first group is used for carrying out multiple calibration and calibration on the parameters in the initial fitting function, and the inverse a is deduced₀、a₁、a₂And a₃A value of, e.g. a₀＝67.003、a₁＝-0.998、a₂＝0.00887、a₃-0.0000312. Therefore, after the fitting function and the parameters of the fitting function are determined (namely, the target fitting function is obtained), the amplitude of the lightning current recording card can be read by acquiring the envelope data of the magnetic stripe data of the lightning current recording card.

According to the lightning current method provided by the embodiment of the disclosure, P lightning current recording cards are obtained, lightning impulse simulation experiments with different amplitudes are respectively carried out on the P lightning current recording cards, a lightning current peak value and corresponding magnetic stripe data of each lightning current recording card are obtained, and envelope data of the magnetic stripe data of each lightning current recording card are calculated; fitting to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording cards by adopting the lightning current peak values of the M lightning current recording cards and the envelope data of the corresponding magnetic stripe data; and calibrating parameters in the initial fitting function by adopting the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data to obtain a target fitting function. Therefore, determination that the precision is not high in the existing slope method is made up, meanwhile, the detection range can reach 0-300 kA, the whole natural lightning range is covered, amplitude reading of the lightning current recording card can be achieved in all directions, and accuracy of lightning current detection is improved.

Based on the lightning current peak value method provided by the embodiment corresponding to fig. 1, another embodiment of the present disclosure provides a lightning current peak value calibration method, which is applied to a lightning current recording card reader, where the lightning current recording card reader is composed of an acquisition circuit, a data processing circuit, an automatic card reader, function keys, and a liquid crystal display. Referring to fig. 2, a card reader of a lightning current recording card is initialized, the lightning current recording card is inserted into the card reader, and a card reading key operation is performed, at this time, an acquisition circuit performs AD sampling to acquire magnetic stripe data, the magnetic stripe data is converted into hexadecimal data after digital processing, a data processing circuit performs filtering and amplification processing on the acquired magnetic stripe data, and an envelope area, i.e., a magnetic area, of the magnetic stripe data is calculated. Fig. 3 shows a graph of magnetic stripe data of a 50kA thunder current recording card, wherein the horizontal axis represents the number of collected points, the vertical axis represents the magnetic stripe data, because the magnetic stripe data is an irregular graph, the magnetic area, namely the area of a curved edge graph, can be approximately replaced by a rectangular area for the area of the curved edge graph, is divided into small curved edge graphs with intervals of 1 time unit, and then is summed after being replaced by the rectangular area. Approximate value of magnetic area S:when the sum of Δ x → 0 is larger,n → ∞. When Δ x is 1 and n is 3000, the magnetic area is obtained by calculating the area of 3000 small curved side patterns.

The lightning current is defined as 0kA in the full magnetic state. A standard lightning impulse current is generated by an impulse current generator to carry out a simulation test, and lightning current recording cards recording simulation lightning current amplitudes are used as standard cards to respectively record lightning current values at intervals of 10kA within the range of 0-300 kA (which means that 30 lightning current recording cards are needed). And fitting a function of the corresponding relation between the magnetic area and the lightning current peak value by using a least square method and a filtering algorithm by reading the magnetic area of the lightning current recording card in which different lightning current peak values are stored. And sequentially selecting first-order, second-order, third-order and fourth-order functions for fitting. And fitting the curve graphs for comparison, and optimally obtaining a third-order function. And finally, performing a simulation test through 8/20 mu s and 10/350 mu s standard lightning impulse currents generated by a laboratory impulse current generator, taking a lightning current recording card for recording the amplitude of the simulated lightning current as a standard card, calibrating the parameters of a fitting function of a lightning current recording card reader, reversely deducing the parameters of the fitting function, and storing and displaying data.

The embodiment of the disclosure provides a high-precision calibration method for completing calibration of a lightning current peak value by calculating the envelope area of magnetic stripe data of a lightning current recording card and combining a least square fitting algorithm and performing a simulation test by using 8/20 mu s and 10/350 mu s standard lightning impulse currents generated by a lightning laboratory impulse current generator. The method has the outstanding advantages that the amplitude detection range of the lightning current recording card is improved by calculating the envelope area of the magnetic stripe data, and the full-range detection of 0-300 kA is realized. Meanwhile, the precision of the full range is improved to be less than or equal to +/-10 kA by using least square fitting and filtering algorithm and laboratory standard data calibration. And the accuracy and the reliability of reading the amplitude of the lightning current recording card are improved, and accurate and effective lightning stroke data are provided for customers.

Based on the lightning current peak calibration method described in the embodiment corresponding to fig. 1, the following is an embodiment of the apparatus of the present disclosure, which may be used to implement the embodiment of the method of the present disclosure.

The embodiment of the present disclosure provides a lightning current peak value calibration apparatus, as shown in fig. 4, the lightning current peak value calibration apparatus 40 includes:

the first obtaining module 401 is configured to obtain P lightning current recording cards, where the P lightning current recording cards are lightning current recording cards that are not in a full magnetic state due to lightning strike;

a second obtaining module 402, configured to perform lightning impulse simulation experiments with different amplitudes on the P lightning current recording cards, respectively, and obtain a lightning current peak value and corresponding magnetic stripe data of each lightning current recording card;

a calculating module 403, configured to calculate envelope data of magnetic stripe data of each lightning current recording card;

a fitting module 404, configured to fit the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data to obtain an initial fitting function of the lightning current peak values and the envelope data of the lightning current recording cards;

a calibration module 405, configured to calibrate parameters in the initial fitting function by using the lightning current peak values of the N lightning current recording cards and the envelope data of the corresponding magnetic stripe data, so as to obtain a target fitting function, where P is M + N.

In an embodiment, the second obtaining module 402 is configured to obtain an amplitude range of the lightning impulse current, and divide the amplitude range of the lightning impulse current according to a preset interval to obtain M sub-intervals; carrying out lightning impulse simulation experiments with different amplitudes on M lightning current recording cards in the P lightning current recording cards according to M sub-intervals, and determining the maximum value of the interval end points of the M sub-intervals as the lightning current peak value of each lightning current recording card; dividing N lightning current recording cards in the P lightning current recording cards into two groups, respectively carrying out 8/20 mu s lightning impulse simulation test on each lightning current recording card in the first group, respectively carrying out 10/350 mu s lightning impulse simulation test on each lightning current recording card in the second group, and obtaining the lightning current peak value of each lightning current recording card in the N lightning current recording cards.

In one embodiment, the second obtaining module 402 is configured to obtain magnetic stripe data of each lightning current recording card through a lightning current recording card reader.

In one embodiment, the envelope data comprises an envelope area or an envelope length

In an embodiment, the calculating module 403 is configured to calculate, by using a first formula, envelope data of magnetic stripe data of each lightning current recording card when the envelope data is an envelope area, where the magnetic stripe data is a curved edge pattern, and the envelope data is an area of the curved edge pattern;

the first formula is:where S denotes envelope data, n denotes the number of divided sections for a curved edge pattern, Δ x denotes a time unit of the divided section interval, and f (δ)_i) Is expressed at delta_iThe value of (c).

In an embodiment, the fitting module 404 is configured to fit the lightning current peak values of the M lightning current recording cards and the corresponding envelope data of the magnetic stripe data by using a least square method and a filtering algorithm to obtain an initial fitting function of the lightning current peak values and the envelope data.

In one embodiment, the initial fitting function is a third order function.

In one embodiment, the calibration module is configured to calibrate parameters in the initial fitting function by using a lightning current peak value of each lightning current recording card in the first group and envelope data of corresponding magnetic stripe data to obtain a first target fitting function;

and the calibration module is used for calibrating the parameters in the initial fitting function by adopting the lightning current peak value of each lightning current recording card in the second group and the envelope data of the corresponding magnetic stripe data to obtain a second target fitting function, and the parameters of the first target fitting function are different from the parameters of the second target fitting function.

According to the lightning current peak value calibration device provided by the embodiment of the disclosure, the envelope data of the magnetic stripe data of the lightning current recording card is calculated, and a least square fitting algorithm is combined, so that a simulation test is performed by using 8/20 mu s and 10/350 mu s standard lightning impulse currents generated by an impulse current generator in a lightning laboratory, and a high-precision calibration method for calibrating the lightning current peak value is completed. By calculating the envelope data of the magnetic stripe data, the amplitude detection range of the lightning current recording card is enlarged, and 0-300 kA full-range detection is realized. Meanwhile, the precision of the full range is improved to be less than or equal to +/-10 kA by using least square fitting and filtering algorithm and laboratory standard data calibration. And the accuracy and the reliability of reading the amplitude of the lightning current recording card are improved, and accurate and effective lightning stroke data are provided for customers.

The embodiment of the present disclosure further provides a lightning current peak calibration apparatus, where the lightning current peak calibration apparatus includes a receiver, a transmitter, a memory, and a processor, where the transmitter and the memory are respectively connected to the processor, the memory stores at least one computer instruction, and the processor is configured to load and execute the at least one computer instruction, so as to implement the lightning current peak calibration method described in the embodiment corresponding to fig. 1.

Based on the method for calibrating the peak value of the lightning current described in the embodiment corresponding to fig. 1, an embodiment of the present disclosure further provides a computer-readable storage medium, for example, the non-transitory computer-readable storage medium may be a Read Only Memory (ROM), a Random Access Memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like. The storage medium stores computer instructions for executing the lightning current peak calibration method described in the embodiment corresponding to fig. 1, which is not described herein again.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program instructing relevant hardware, where the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.