Lightning stroke sensor

Abstract

The invention discloses a lightning stroke sensor, which is used for solving the problem of how to smoothly collect lightning stroke parameters and implement the lightning stroke parameters in an actual application environment when the lightning stroke parameters are researched. The lightning stroke sensor comprises a 1.2 / 50 [mu] s lightning current amplitude sampling circuit and a time width sampling circuit which is connected with the lightning current amplitude sampling circuit and is constructed based on a general comparator circuit and an RC circuit. The time width sampling circuit sequentially comprises a wave head time width sampling circuit, a half-wave time width sampling circuit and a full-wave time width sampling circuit; wherein the lightning current amplitude sampling circuit is used for outputting an amplitude sampling level of a lightning stroke waveform; the wave head time width sampling circuit is used for collecting the wave head time of the lightning stroke waveform; the half-wave time width sampling circuit is used for collecting the half-wave time of the lightning stroke waveform; the full-wave time width sampling circuit is used for collecting the full-wave time of the lightning stroke waveform. Therefore, lightning parameters can be smoothly acquired, and the method can be implemented in an actual application environment.

Description

Technical Field

[0001] The invention relates to the technical field of lightning protection, and in particular to a lightning strike sensor. Background Art

[0002] The current lightning parameter acquisition instruments usually collect the peak value and occurrence time of lightning strikes, but do not reflect the parameter value of the lightning current waveform. Furthermore, in order to study the characteristics of lightning current and the characteristics of corresponding protection devices, according to relevant design specifications, the definition of lightning current parameters (hereinafter referred to as lightning parameters) is as follows: Figure 1 shown.

[0003] To study the characteristics of lightning current, it is necessary to study the rising edge time of lightning current (i.e. wave head time t1), current peak, half-wave time t2, and full-wave time t. As a result, a method of collecting lightning current waveforms during the lightning occurrence period in a time series has emerged. The current implementation method, such as oscilloscope sampling in the laboratory, since the lightning waveform usually occurs within a few hundred microseconds (μS), in order to better restore the lightning current waveform and the time parameters of the waveform, its sampling period should not be greater than 100 nanoseconds. This means that the acquisition of lightning parameters requires the use of high AD sampling (Analog-to-Digital Conversion) frequency and laboratory environmental conditions.

[0004] However, in actual applications, how to achieve and maintain laboratory environmental conditions while having good cost-effectiveness has always been a difficulty in promoting the application of lightning parameter acquisition instruments. For example, in order to monitor the lightning strikes of the 10kV (kilovolt) transmission lines of the power system and make corresponding lightning protection plans, it is necessary to install lightning monitoring equipment on multiple towers. It is obviously not suitable and difficult to build a laboratory environment in the field. Summary of the invention

[0005] The present invention provides a lightning strike sensor for solving or partially solving the technical problem of how to smoothly collect lightning parameters when studying lightning strike parameters and how to implement the sensor in a practical application environment.

[0006] The present invention provides a lightning strike sensor, which comprises a 1.2 / 50μs lightning current amplitude sampling circuit, and a time width sampling circuit based on a universal comparator circuit and an RC circuit and connected to the lightning current amplitude sampling circuit; the time width sampling circuit comprises a wave head time width sampling circuit, a half-wave time width sampling circuit and a full-wave time width sampling circuit in sequence; wherein the lightning current amplitude sampling circuit is used to output an amplitude sampling level of a lightning strike waveform; the wave head time width sampling circuit is used to collect the wave head time of the lightning strike waveform; the half-wave time width sampling circuit is used to collect the half-wave time of the lightning strike waveform; and the full-wave time width sampling circuit is used to collect the full-wave time of the lightning strike waveform.

[0007] Optionally, the lightning strike sensor further includes a lightning strike waveform signal follower; the lightning strike waveform signal follower is composed of a comparator A1; the lightning strike waveform signal follower is used to absorb transient impacts of the lightning strike waveform to buffer the lightning strike waveform and reduce signal distortion.

[0008] Optionally, the lightning current amplitude sampling circuit is composed of a comparator A2, a comparator A3, a diode D1, a capacitor C1 and a resistor R3; the diode D1 and the capacitor C1 are connected in series between the comparator A2 and the comparator A3, and the resistor R3 is connected in parallel between the comparator A2 and the comparator A3.

[0009] Optionally, a comparator A4 is further provided between the lightning current amplitude sampling circuit and the wave front time width sampling circuit, and the comparator A4 is used to output an amplitude following level to determine the wave front time and the half-wave time.

[0010] Optionally, the wave head time width sampling circuit is composed of a comparator A6, a resistor R11, a resistor R12, a resistor R13, a resistor R14 and a capacitor C2; the resistor R11 and the resistor R12 connected in series are connected in parallel at both ends of the resistor R13 and the resistor R14 connected in series; the positive electrode of the comparator A6 is connected between the resistor R11 and the resistor R12, and the negative electrode is connected between the resistor R13 and the resistor R14; one end of the capacitor C2 is connected to one end of the resistor R13, and the other end is connected to the negative electrode of the comparator A6.

[0011] Optionally, a first ratio of the resistor R12 to the resistor R11 is greater than a second ratio of the resistor R14 to the resistor R13, and a difference between the first ratio and the second ratio is within a preset ratio difference range.

[0012] Optionally, the half-wave time width sampling circuit is composed of a comparator A7, a resistor R21, a resistor R22, a resistor R23, a resistor R24 ​​and a capacitor C3; the resistor R24, the resistor R23, the resistor R21 and the resistor R22 are connected in series in sequence; the end of the resistor R22 not connected to the resistor R21 is connected to the full-wave time width sampling circuit; the end of the resistor R24 ​​not connected to the resistor R23 is connected to the wave head time width sampling circuit; the positive electrode of the comparator A7 is connected between the resistor R21 and the resistor R22, and the negative electrode is connected between the resistor R23 and the resistor R24; one end of the capacitor C3 is connected in parallel between the resistor R23 and the resistor R21, and the other end is connected to the negative electrode of the comparator A7.

[0013] Optionally, the resistance value of the resistor R23 is equal to the resistance value of the resistor R24; the first resistance value of the resistor R22 is less than the second resistance value of the resistor R21, and the difference between the first resistance value and the second resistance value is greater than or equal to a preset resistance difference threshold.

[0014] Optionally, the full-wave time width sampling circuit is composed of a comparator A5, a resistor R1 and a resistor R2; the positive electrode of the comparator A5 is connected to the lightning waveform signal follower and the half-wave time width sampling circuit, and the negative electrode is connected to the resistor R1; the resistor R2 is connected in parallel between the comparator A5 and the resistor R1.

[0015] Optionally, the lightning strike sensor also includes a sampling control microcontroller, which is provided with a control program; the sampling control microcontroller is used to combine the inherent continuity characteristics of the current waveform, and to determine the shape of the lightning strike waveform and measure the amount of lightning current by calculating and comparing the wave head time, the half-wave time and the full-wave time.

[0016] It can be seen from the above technical solutions that the present invention has the following advantages:

[0017] A lightning strike sensor is provided. The lightning strike sensor includes a 1.2 / 50μs lightning current amplitude sampling circuit, a time width sampling circuit based on a general comparator circuit and an RC circuit connected to the lightning current amplitude sampling circuit; the time width sampling circuit includes a wave head time width sampling circuit, a half-wave time width sampling circuit and a full-wave time width sampling circuit in sequence; wherein the lightning current amplitude sampling circuit is used to output the amplitude sampling level of the lightning strike waveform; the wave head time width sampling circuit is used to collect the wave head time of the lightning strike waveform; the half-wave time width sampling circuit is used to collect the half-wave time of the lightning strike waveform; and the full-wave time width sampling circuit is used to collect the full-wave time of the lightning strike waveform. Thus, the lightning strike sensor provided by the present invention can not only smoothly collect lightning parameters, but also be implemented in a practical application environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 is a schematic diagram of lightning strike parameters;

[0020] Figure 2 The present invention is a schematic diagram of the circuit principle of a lightning strike sensor;

[0021] Figure 3 A schematic diagram of an example of a sampling waveform obtained based on a lightning strike sensor; DETAILED DESCRIPTION

[0022] The embodiment of the present invention provides a lightning strike sensor for solving or partially solving the technical problem of how to smoothly collect lightning parameters when studying lightning strike parameters and how to implement the sensor in an actual application environment.

[0023] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] As an example, to study the characteristics of lightning current, it is necessary to study the rising edge time of lightning current (i.e. wave head time t1), current peak, half-wave time t2, and full-wave time t. As a result, a method of collecting lightning current waveforms during the lightning occurrence period in time series has emerged. The current implementation method, such as oscilloscope sampling in the laboratory, since the lightning waveform usually occurs within a few hundred microseconds (μS), in order to better restore the lightning current waveform and the time parameters of the waveform, its sampling period should not be greater than 100 nanoseconds. This means that the acquisition of lightning parameters requires the use of a high AD sampling frequency and laboratory environmental conditions.

[0025] However, in actual applications, how to achieve and maintain laboratory environmental conditions while having good cost-effectiveness has always been a difficulty in promoting the application of lightning parameter acquisition instruments. For example, in order to monitor the lightning strikes of the 10kV (kilovolt) transmission lines of the power system and make corresponding lightning protection plans, it is necessary to install lightning monitoring equipment on multiple towers. It is obviously not suitable and difficult to build a laboratory environment in the field.

[0026] Therefore, one of the core invention points of the embodiment of the present invention is: in view of the shortcomings of the prior art, a lightning strike sensor is provided by adopting an analog charging and discharging circuit, a comparator, a pulse timing and a single-chip microcomputer controlled sampling scheme. Among them, the lightning strike sensor is mainly composed of a lightning strike waveform signal follower, a 1.2 / 50μs lightning current amplitude sampling circuit, a wave head time width sampling circuit, a half-wave time width sampling circuit, a full-wave time width sampling circuit, and a sampling control single-chip microcomputer and a control program for recording the wave head time, half-wave time, full-wave time, lightning current amplitude and lightning current occurrence time. By constructing a stable and mature time width sampling circuit based on a general comparator circuit and an RC circuit (Resistor-Capacitor Circuit, a simple circuit composed of a resistor (R) and a capacitor (C)), the lightning current time parameter sampling only needs to sample the pulse width measurement time, which effectively solves the high sampling frequency problem of time series digital sampling similar to an oscilloscope, so that the lightning parameters that need to be studied can be collected and implemented in a practical application environment. In addition, the lightning strike sensor provided by the present invention can also realize that the sampling of the lightning current waveform period can give priority to the time pulse width measurement, and there is no waveform current value sampling during the period, thereby simplifying the sampling process, reducing the load of the sampling control system, and facilitating the sampling of lightning strike parameters with better cost-effectiveness. Furthermore, the comparator circuit and the RC circuit can better resist the electromagnetic interference of the lightning strike environment, thereby improving the sampling success rate.

[0027] Reference Figure 2 , shows a schematic diagram of the circuit principle of a lightning strike sensor provided by an embodiment of the present invention.

[0028] Combination Figure 2 The lightning strike sensor can mainly include a 1.2 / 50μs lightning current amplitude sampling circuit, and a time width sampling circuit based on a general comparator circuit and an RC circuit connected to the lightning current amplitude sampling circuit. Specifically, in the embodiment of the present invention, based on the general comparator circuit and the RC circuit, a wave head time t1 width sampling circuit, a half-wave time t2 width sampling circuit and a full-wave time t width sampling circuit are sequentially constructed.

[0029] The lightning strike sensor also includes a lightning strike waveform signal follower. The lightning strike waveform signal follower is composed of a comparator A1. The lightning strike waveform signal follower, that is, the positive pole of the comparator A1 is connected to the input lightning strike waveform signal, which is used to absorb the transient impact of the lightning strike waveform to buffer the lightning strike waveform and reduce signal distortion. The negative pole and output end of the comparator A1 are connected to the lightning current amplitude sampling circuit (specifically, the positive pole of the comparator A2). At the same time, the output end of the comparator A1 is also connected to the half-wave time t2 width sampling circuit (specifically, the resistor R22) and the full-wave time t width sampling circuit (specifically, the positive pole of the comparator A5).

[0030] The lightning current amplitude sampling circuit is composed of comparator A2, comparator A3, diode D1, capacitor C1 and resistor R3. Diode D1 and capacitor C1 are connected in series between comparator A2 (output end) and comparator A3 (positive pole). Resistor R3 is connected in parallel between comparator A2 and comparator A3. Among them, one end of resistor R3 is connected to the negative pole and output end of comparator A2 at the same time, and the other end is connected to the negative pole and output end of comparator A3 at the same time. In specific applications, the lightning current amplitude sampling circuit is mainly used to output the amplitude sampling level PK_ADC of the lightning waveform.

[0031] A comparator A4 is also provided between the lightning current amplitude sampling circuit (specifically the output end of the comparator A3) and the wave head time t1 width sampling circuit (specifically the parallel connection point of the resistor R12 and the resistor R14). Specifically, the output end of the comparator A3 is connected to the positive electrode of the comparator A4, and the negative electrode and the output end of the comparator A4 are connected to the parallel connection point of the resistor R12 and the resistor R14. The comparator A4 is used to output the amplitude following level to determine the wave head time and the half-wave time. In addition, the output end of the comparator A4 is also connected to the resistor R24 ​​of the half-wave time t2 width sampling circuit.

[0032] Next, combine Figure 2 The wave head time t1 width sampling circuit, half wave time t2 width sampling circuit and full wave time t width sampling circuit are introduced respectively.

[0033] (I) Wave head time t1 width sampling circuit

[0034] In practical applications, the wave head time t1 width sampling circuit is mainly used to collect the wave head time t1 of the lightning waveform (corresponding to Figure 2 OUT in the .

[0035] The wave head time t1 width sampling circuit is composed of a comparator A6, a resistor R11, a resistor R12, a resistor R13, a resistor R14 and a capacitor C2. The resistors R11 and R12 connected in series are connected in parallel to the two ends of the resistors R13 and R14 connected in series. The positive electrode of the comparator A6 is connected between the resistors R11 and R12, and the negative electrode is connected between the resistors R13 and R14. One end of the capacitor C2 is connected to one end of the resistor R13, and the other end is connected to the negative electrode of the comparator A6.

[0036] Among them, the first ratio of resistor R12 to resistor R11 is greater than the second ratio of resistor R14 to resistor R13, and the difference between the first ratio and the second ratio is within a preset ratio difference range (set according to actual conditions, the first ratio can be slightly greater than the second ratio).

[0037] The working principle of the wave head time t1 width sampling circuit can be understood as follows: the positive input level of comparator A6 V A At the comparator A5 positive input level V IN When the rising edge is higher than the negative input level of comparator A6 V B At this time, comparator A6 outputs a high level. When V IN Reaching the amplitude V PK After that, by charging capacitor C2, V B Higher than V A , comparator A6 outputs a low level.

[0038] In a specific implementation, the resistance ratio of R12 / R11 can be slightly larger than R14 / R13. With the charging delay of capacitor C2, when V IN At the rising edge, V PK In the rising state. Due to the charging delay of capacitor C2, V IN The entire rising edge V A Level V B High, comparator A6 output T1_OUT is high level.

[0039] When V IN Reaching amplitude, V PK After maintaining unchanged, capacitor C2 continues to charge until the circuit is balanced. It can be seen that when designing a circuit, the continuous charging time should be kept suitable for the timing accuracy of the design. The corresponding process is: at V PK After maintaining unchanged, V A Remains unchanged, and capacitor C2 continues to be charged through resistor R14, V B The level rises.

[0040] Since the resistance ratio of R12 / R11 is slightly larger than that of R14 / R13, after the circuit reaches equilibrium, V B Level higher than V A , the comparator A6 outputs T1_OUT at a low level. The corresponding t1 width when T1_OUT changes from a high level to a low level is the wave head time.

[0041] Generally speaking, the design time accuracy is no more than 100 nanoseconds. PK After maintaining the same state, capacitor C2 is charged, causing V B Level higher than V A This period of time should not be greater than the time accuracy design value. For example, if R11=R12=R14=100K, R13=110K, C2=0.47PF, the charging time of capacitor C2 is estimated to be less than 47 nanoseconds.

[0042] (II) Half-wave time t2 width sampling circuit

[0043] In practical applications, the half-wave time t2 width sampling circuit is mainly used to collect the half-wave time t2 of the lightning waveform (corresponding to Figure 2 OUT in the output).

[0044] The half-wave time t2 width sampling circuit is composed of a comparator A7, a resistor R21, a resistor R22, a resistor R23, a resistor R24 ​​and a capacitor C3. Among them, the resistor R24, the resistor R23, the resistor R21 and the resistor R22 are connected in series in sequence. The end of the resistor R22 that is not connected to the resistor R21 is connected to the full-wave time width sampling circuit, specifically connected to the positive pole of the comparator A5, and is also connected to the negative pole of the comparator A1. The end of the resistor R24 ​​that is not connected to the resistor R23 is connected to the wave head time width sampling circuit, specifically connected to the parallel point of the resistor R12 and R14, and is also connected to the output end of the comparator A4. The positive pole of the comparator A7 is connected between the resistor R21 and the resistor R22, and the negative pole is connected between the resistor R23 and the resistor R24. One end of the capacitor C3 is connected in parallel between the resistor R23 and the resistor R21, and the other end is connected to the negative pole of the comparator A7.

[0045] The resistance value of the resistor R23 is equal to the resistance value of the resistor R24. The first resistance value of the resistor R22 is less than the second resistance value of the resistor R21, and the difference between the first resistance value and the second resistance value is greater than or equal to the preset resistance difference threshold. The preset resistance difference threshold is set according to actual conditions, and the first resistance value of the resistor R22 is much smaller than the second resistance value of the resistor R21.

[0046] The working principle of the half-wave time t2 width sampling circuit can be understood as follows: the resistor R22 is much smaller than the resistor R21, and the resistor R24=R23. At this time, the positive input level of comparator A7 is V C The value of ≈V IN Comparator A7 negative input level V D In V IN During the rising edge, due to the delay of capacitor C3, V C Level higher than V D , comparator A7 outputs T2_OUT as high level. IN After reaching the amplitude, V PK After charging capacitor C3, V D =1 / 2V PK unchanged. As the input V IN When the level drops, V IN Less than 1 / 2V PK After that, the comparator A7 outputs T2_OUT as a low level. The corresponding t2 width when T2_OUT changes from high level to low level is the half-wave time.

[0047] (III) Full-wave time t width sampling circuit

[0048] In practical applications, the full-wave time t width sampling circuit is mainly used to collect the full-wave time t of the lightning waveform (corresponding to Figure 2 in T_OUT).

[0049] The full-wave time width sampling circuit is composed of comparator A5, resistor R1 and resistor R2. The positive electrode of comparator A5 is connected to the lightning waveform signal follower (output end of A1) and the half-wave time width sampling circuit (resistor R22), and the negative electrode is connected to resistor R1. Resistor R2 is connected in parallel between comparator A5 and resistor R1.

[0050] The working principle of the lightning current full-wave time t width circuit can be understood as follows: the ratio of resistors R1 and R2 is taken to make the negative input level V L is low enough (according to the sampling accuracy setting) and is a fixed value. IN Greater than V L When the comparator A5 outputs T_OUT at high level, the full-wave time width t is obtained until the input is less than the designed value.

[0051] Furthermore, the lightning strike sensor may also include a sampling control microcontroller. The sampling control microcontroller is provided with a control program. The sampling control microcontroller is used to determine the shape of the lightning strike waveform and measure the amount of the lightning current by calculating and comparing the wave head time t1, the half-wave time t2 and the full-wave time t in combination with the inherent continuity characteristics of the current waveform.

[0052] The single-chip microcomputer and its sampling control principle can be understood as follows: Compared with sampling at time points in time sequence, the circuit design of the lightning strike sensor provided in the embodiment of the present invention enables the sampling of the wave head time t1, the half-wave time t2, and the full-wave time t to only perform the level judgment action, and finally sample PK_ADC as the amplitude. This can not only reflect the main parameters of the lightning current wave truthfully, but also greatly simplify the circuit design to achieve the purpose of stability and high efficiency. The lightning strike waveform can be outlined by the PK_ADC value and the t, t1, t2 values, as well as the continuity characteristics of the current change.

[0053] In an embodiment of the present invention, a lightning strike sensor is provided. The lightning strike sensor is mainly composed of a lightning strike waveform signal follower, a 1.2 / 50μs lightning current amplitude sampling circuit, a wave head time width sampling circuit, a half-wave time width sampling circuit, a full-wave time width sampling circuit, and a sampling control single chip microcomputer and a control program for recording the wave head time, half-wave time, full-wave time, lightning current amplitude and lightning current occurrence time. By constructing a stable and mature time width sampling circuit based on a general comparator circuit and an RC circuit, the lightning current time parameter sampling only needs to sample the pulse width measurement time, which effectively solves the high sampling frequency problem of the time series digital sampling similar to an oscilloscope, so that the lightning parameters to be studied can be collected and implemented in a practical application environment. In addition, the lightning strike sensor provided by the present invention can also realize that the sampling of the lightning current waveform period can give priority to the time pulse width measurement, and there is no waveform current value sampling during the period, thereby simplifying the sampling process, reducing the load of the sampling control system, and facilitating the sampling of lightning strike parameters at a better cost-effectiveness. Furthermore, the comparator circuit and the RC circuit can better resist the electromagnetic interference of the lightning strike environment, thereby improving the sampling success rate.

[0054] To facilitate understanding, the embodiments of the present invention are described below by using specific examples.

[0055] In this example, based on Figure 2 Based on the circuit schematic diagram, an application circuit example was established.

[0056] Among them, the comparator A1 of the lightning waveform signal follower adopts the THS4222 (a high-performance, low-power broadband operational amplifier) ​​high-speed operational amplifier.

[0057] Comparators A2 and A3 in the lightning current amplitude sampling circuit use THS4222 high-speed operational amplifiers, diode D1 uses Schottky diode voltage drop, and resistor R3 uses a non-inductive resistor.

[0058] In the wave head time width sampling circuit, resistors R12=R14=R13=50K, R11=47K, and comparator A6 uses THS4222 high-speed operational amplifier.

[0059] In the half-wave time width sampling circuit, resistors R21=R24=R23=100K, R22=1K, and comparator A7 uses THS4222 high-speed operational amplifier.

[0060] In the full-wave time width sampling circuit, resistor R1=100K, R2=1K, and comparator A5 uses THS4222 high-speed operational amplifier.

[0061] According to the specific settings in this example, Figure 3The following is a schematic diagram showing an example of a 1.2 / 50μS sampling waveform obtained by a lightning strike sensor. Channel 1 corresponds to the wave head time t1, and channel 2 corresponds to the half-wave time t2.

[0062] It is understandable that other circuit examples constructed by adjusting circuit parameters according to the technical solution and related schematic diagrams provided by the present invention are also within the protection scope of the present invention. More circuit examples of time sampling circuits can be deduced based on the principles of the present invention, which will not be described here.

[0063] It should be noted that, in order to enable those skilled in the art to better distinguish data of the same type but with different actual meanings, some technical features are distinguished by the first and the second in the embodiments of the present invention. The first and the second are only used for data distinction and have no other special meanings. It can be understood that the present invention is not limited to this.

[0064] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lightning strike sensor, characterized in that: The lightning strike sensor includes a 1.2 / 50μs lightning current amplitude sampling circuit, and a time width sampling circuit constructed based on a universal comparator circuit and an RC circuit connected to the lightning current amplitude sampling circuit; the time width sampling circuit includes a wave head time width sampling circuit, a half-wave time width sampling circuit and a full-wave time width sampling circuit in sequence; wherein the lightning current amplitude sampling circuit is used to output the amplitude sampling level of the lightning strike waveform; the wave head time width sampling circuit is used to collect the wave head time of the lightning strike waveform; the half-wave time width sampling circuit is used to collect the half-wave time of the lightning strike waveform; and the full-wave time width sampling circuit is used to collect the full-wave time of the lightning strike waveform.

2. The lightning strike sensor according to claim 1, characterized in that: The lightning strike sensor also includes a lightning strike waveform signal follower; the lightning strike waveform signal follower is composed of a comparator A1; the lightning strike waveform signal follower is used to absorb the transient impact of the lightning strike waveform to buffer the lightning strike waveform and reduce signal distortion.

3. The lightning strike sensor according to claim 2, characterized in that: The lightning current amplitude sampling circuit is composed of a comparator A2, a comparator A3, a diode D1, a capacitor C1 and a resistor R3; the diode D1 and the capacitor C1 are connected in series between the comparator A2 and the comparator A3, and the resistor R3 is connected in parallel between the comparator A2 and the comparator A3.

4. The lightning strike sensor according to claim 3, characterized in that: A comparator A4 is further provided between the lightning current amplitude sampling circuit and the wave crest time width sampling circuit. The comparator A4 is used to output an amplitude following level to determine the wave crest time and the half-wave time.

5. The lightning strike sensor according to claim 2, characterized in that: The wave head time width sampling circuit is composed of a comparator A6, a resistor R11, a resistor R12, a resistor R13, a resistor R14 and a capacitor C2; the resistor R11 and the resistor R12 connected in series are connected in parallel at both ends of the resistor R13 and the resistor R14 connected in series; the positive electrode of the comparator A6 is connected between the resistor R11 and the resistor R12, and the negative electrode is connected between the resistor R13 and the resistor R14; one end of the capacitor C2 is connected to one end of the resistor R13, and the other end is connected to the negative electrode of the comparator A6.

6. The lightning strike sensor according to claim 5, characterized in that: A first ratio of the resistor R12 to the resistor R11 is greater than a second ratio of the resistor R14 to the resistor R13 , and a difference between the first ratio and the second ratio is within a preset ratio difference range.

7. The lightning strike sensor according to claim 2, characterized in that: The half-wave time width sampling circuit is composed of a comparator A7, a resistor R21, a resistor R22, a resistor R23, a resistor R24 ​​and a capacitor C3; the resistor R24, the resistor R23, the resistor R21 and the resistor R22 are connected in series in sequence; the end of the resistor R22 not connected to the resistor R21 is connected to the full-wave time width sampling circuit; the end of the resistor R24 ​​not connected to the resistor R23 is connected to the wave head time width sampling circuit; the positive electrode of the comparator A7 is connected between the resistor R21 and the resistor R22, and the negative electrode is connected between the resistor R23 and the resistor R24; one end of the capacitor C3 is connected in parallel between the resistor R23 and the resistor R21, and the other end is connected to the negative electrode of the comparator A7.

8. The lightning strike sensor according to claim 7, characterized in that: The resistance value of the resistor R23 is equal to the resistance value of the resistor R24; the first resistance value of the resistor R22 is less than the second resistance value of the resistor R21, and the difference between the first resistance value and the second resistance value is greater than or equal to a preset resistance difference threshold.

9. The lightning strike sensor according to claim 2, characterized in that: The full-wave time width sampling circuit is composed of a comparator A5, a resistor R1 and a resistor R2; the positive electrode of the comparator A5 is connected to the lightning waveform signal follower and the half-wave time width sampling circuit, and the negative electrode is connected to the resistor R1; the resistor R2 is connected in parallel between the comparator A5 and the resistor R1.

10. The lightning strike sensor according to any one of claims 1 to 9, characterized in that: The lightning strike sensor also includes a sampling control single chip microcomputer, which is provided with a control program; the sampling control single chip microcomputer is used to combine the inherent continuity characteristics of the current waveform, and by calculating and comparing the wave head time, the half-wave time and the full-wave time, determine the shape of the lightning strike waveform and measure the amount of lightning current.

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