A lightning strike sensor

Abstract

This invention discloses a lightning strike sensor to address the problem of successfully acquiring lightning parameters and implementing the sensor in practical application environments when studying lightning strike parameters. The lightning strike sensor includes a 1.2 / 50μs lightning current amplitude sampling circuit and a time-width sampling circuit constructed based on a general comparator circuit and an RC circuit, connected to the lightning current amplitude sampling circuit. The time-width sampling circuit sequentially includes a wavefront time-width sampling circuit, a half-wave time-width sampling circuit, and a full-wave time-width sampling circuit. Specifically, the lightning current amplitude sampling circuit outputs the amplitude sampling level of the lightning strike waveform; the wavefront time-width sampling circuit acquires the wavefront time of the lightning strike waveform; the half-wave time-width sampling circuit acquires the half-wave time of the lightning strike waveform; and the full-wave time-width sampling circuit acquires the full-wave time of the lightning strike waveform. This allows for successful acquisition of lightning parameters and implementation in practical application environments.

Description

Technical Field

[0001] This invention relates to the field of lightning protection technology, and in particular to a lightning strike sensor. Background Technology

[0002] Current lightning strike parameter acquisition instruments typically only collect the peak value and occurrence time of lightning strikes, without reflecting the parameter values ​​of the lightning current waveform. Furthermore, to study the characteristics of lightning current and the characteristics of corresponding protective devices, according to relevant design specifications, the definition of lightning strike current parameters (hereinafter referred to as lightning parameters) is as follows: Figure 1 As shown.

[0003] Studying the characteristics of lightning current requires investigating its rise time (wavefront time t1), peak current, half-wave time t2, and full-wave time t. This has led to methods for acquiring lightning current waveforms over time sequences during lightning strikes. Current implementations, such as laboratory oscilloscope sampling, require a sampling period of no more than 100 nanoseconds to accurately reconstruct the lightning current waveform and its time parameters, since lightning strike waveforms typically occur within a few hundred microseconds (μS). This implies that lightning strike parameter acquisition requires high analog-to-digital (A / D) sampling frequencies and suitable laboratory environments.

[0004] However, in practical applications, achieving and maintaining suitable laboratory environmental conditions while maintaining cost-effectiveness has always been a challenge for the widespread application of lightning strike parameter acquisition instruments. For example, to monitor lightning strikes on 10kV transmission lines of a power system and develop corresponding lightning protection plans, lightning monitoring equipment needs to be installed on multiple towers. Building a laboratory environment in the field is clearly unsuitable and difficult to implement. Summary of the Invention

[0005] This invention provides a lightning strike sensor to solve or partially solve the technical problem of how to successfully collect lightning parameters when studying lightning strike parameters and implement the sensor in a practical application environment.

[0006] This invention provides a lightning strike sensor, which includes a 1.2 / 50μs lightning current amplitude sampling circuit and a time width sampling circuit constructed based on a general comparator circuit and an RC circuit connected to the lightning current amplitude sampling circuit. The time width sampling circuit sequentially includes a wavefront time width sampling circuit, a half-wave time width sampling circuit, and a full-wave time width sampling circuit. The lightning current amplitude sampling circuit is used to output the amplitude sampling level of the lightning strike waveform; the wavefront time width sampling circuit is used to acquire the wavefront time of the lightning strike waveform; the half-wave time width sampling circuit is used to acquire the half-wave time of the lightning strike waveform; and the full-wave time width sampling circuit is used to acquire 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 the transient impact of the lightning strike waveform to buffer the lightning strike waveform and reduce signal distortion.

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

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

[0010] Optionally, the wavefront time width sampling circuit consists of a comparator A6, resistors R11, R12, R13, R14, and capacitor C2; resistors R11 and R12, connected in series, are connected in parallel across resistors R13 and R14, which are connected in series; the positive terminal of comparator A6 is connected between resistors R11 and R12, and the negative terminal is connected between resistors R13 and R14; one end of capacitor C2 is connected to one end of resistor R13, and the other end is connected to the negative terminal of comparator A6.

[0011] Optionally, 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.

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

[0013] Optionally, the resistance value of resistor R23 is equal to the resistance value of resistor R24; the first resistance value of resistor R22 is less than the second resistance value of 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 consists of comparator A5, resistor R1, and resistor R2; the positive terminal of comparator A5 is connected to the lightning waveform signal follower and the half-wave time-width sampling circuit, and the negative terminal is connected to resistor R1; resistor R2 is connected in parallel between comparator A5 and resistor R1.

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

[0016] As can be seen from the above technical solutions, 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 and a time-width sampling circuit constructed based on a general comparator circuit and an RC circuit, connected to the lightning current amplitude sampling circuit. The time-width sampling circuit sequentially includes a wavefront time-width sampling circuit, a half-wave time-width sampling circuit, and a full-wave time-width sampling circuit. The lightning current amplitude sampling circuit outputs the amplitude sampling level of the lightning strike waveform; the wavefront time-width sampling circuit acquires the wavefront time of the lightning strike waveform; the half-wave time-width sampling circuit acquires the half-wave time of the lightning strike waveform; and the full-wave time-width sampling circuit acquires the full-wave time of the lightning strike waveform. Therefore, the lightning strike sensor provided by this invention can successfully acquire lightning parameters and can be implemented in practical application environments. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

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

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

[0021] Figure 3 This is a schematic diagram of an example of a sampling waveform obtained based on a lightning strike sensor; Detailed Implementation

[0022] This invention provides a lightning strike sensor to solve or partially solve the technical problem of how to successfully collect lightning parameters while studying them and implement the sensor in a practical application environment.

[0023] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0024] As an example, studying the characteristics of lightning current requires investigating its rise time (i.e., wavefront time t1), peak current, half-wave time t2, and full-wave time t. This has led to methods for acquiring lightning current waveforms over time sequences during lightning strikes. Current implementations, such as laboratory oscilloscope sampling, require a sampling period of no more than 100 nanoseconds to accurately reconstruct the lightning current waveform and its time parameters, since lightning strike waveforms typically occur within a few hundred microseconds (μS). This implies that lightning strike parameter acquisition requires high AD sampling frequencies and specific laboratory environmental conditions.

[0025] However, in practical applications, achieving and maintaining suitable laboratory environmental conditions while maintaining cost-effectiveness has always been a challenge for the widespread application of lightning strike parameter acquisition instruments. For example, to monitor lightning strikes on 10kV transmission lines of a power system and develop corresponding lightning protection plans, lightning monitoring equipment needs to be installed on multiple towers. Building a laboratory environment in the field is clearly unsuitable and difficult to implement.

[0026] Therefore, one of the core inventive points of this invention is that, addressing the shortcomings of existing technologies, a lightning strike sensor is provided by employing an analog charge-discharge circuit, comparator, pulse timing, and microcontroller-controlled sampling scheme. The lightning strike sensor mainly consists of a lightning waveform signal follower, a 1.2 / 50μs lightning current amplitude sampling circuit, a wavefront time width sampling circuit, a half-wave time width sampling circuit, a full-wave time width sampling circuit, and a sampling control microcontroller and control program for recording the wavefront 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-purpose comparator circuit and an RC circuit (a simple circuit composed of resistors (R) and capacitors (C), the lightning current time parameter sampling only requires sampling the pulse width measurement time, effectively solving the high sampling frequency problem of time series digital sampling similar to oscilloscopes. This allows for the collection of the lightning parameters to be studied and enables implementation in practical application environments. Furthermore, the lightning strike sensor provided by this invention can prioritize time pulse width measurement during the sampling of the lightning current waveform, while no waveform current value is sampled during this period. This simplifies the sampling process, reduces the load on the sampling control system, and facilitates lightning strike parameter sampling at a better cost-effectiveness. Moreover, the comparator circuit and RC circuit can effectively resist electromagnetic interference in the lightning strike environment, thereby improving the sampling success rate.

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

[0028] Combination Figure 2 The lightning strike sensor mainly includes 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 this embodiment of the invention, a wavefront 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 based on the general comparator circuit and the RC circuit.

[0029] The lightning strike sensor also includes a lightning strike waveform signal follower. This follower is composed of comparator A1. The positive terminal of comparator A1 is connected to the input lightning strike waveform signal to absorb transient impacts, thus buffering the waveform and reducing signal distortion. The negative terminal and output of comparator A1 are connected to a lightning current amplitude sampling circuit (specifically, the positive terminal of comparator A2). Furthermore, the output of comparator A1 is also connected to a half-wave time t2 width sampling circuit (specifically, resistor R22) and a full-wave time t width sampling circuit (specifically, the positive terminal of comparator A5).

[0030] The lightning current amplitude sampling circuit consists of comparator A2, comparator A3, diode D1, capacitor C1, and resistor R3. Diode D1 and capacitor C1 are connected in series between the output terminal of comparator A2 and the positive terminal of comparator A3. Resistor R3 is connected in parallel across comparator A2 and comparator A3. One end of resistor R3 is connected to both the negative terminal and the output terminal of comparator A2, and the other end is connected to both the negative terminal and the output terminal of comparator A3. In practical applications, the lightning current amplitude sampling circuit is mainly used to output the amplitude sampling level PK_ADC of the lightning strike waveform.

[0031] A comparator A4 is also provided between the lightning current amplitude sampling circuit (specifically, the output of comparator A3) and the wavefront time t1 width sampling circuit (specifically, the parallel connection of resistors R12 and R14). Specifically, the output of comparator A3 is connected to the positive terminal of comparator A4, and the negative terminal and output of comparator A4 are connected to the parallel connection of resistors R12 and R14. Comparator A4 is used to output an amplitude tracking level to determine the wavefront time and half-wave time. Furthermore, the output of comparator A4 is also connected to resistor R24 ​​of the half-wave time t2 width sampling circuit.

[0032] Next, combine Figure 2 The sampling circuits for wavefront time t1 width, half-wave time t2 width, and full-wave time t width are introduced respectively.

[0033] (a) Wavefront time t1 width sampling circuit

[0034] In practical applications, the wavefront time t1 width sampling circuit is mainly used to acquire the wavefront time t1 (corresponding to) of the lightning strike waveform. Figure 2 (T1_OUT in the middle).

[0035] The wavefront time t1 width sampling circuit consists of comparator A6, resistors R11, R12, R13, and R14, and capacitor C2. Resistors R11 and R12, connected in series, are connected in parallel across resistors R13 and R14, which are also connected in series. The positive terminal of comparator A6 is connected between resistors R11 and R12, and the negative terminal is connected between resistors R13 and R14. One end of capacitor C2 is connected to one end of resistor R13, and the other end is connected to the negative terminal of 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 the preset ratio difference range (set according to the actual situation, the first ratio can be slightly greater than the second ratio).

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

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

[0039] When V IN Reaching amplitude, V PK After remaining constant, capacitor C2 continues to charge until the circuit reaches equilibrium. Therefore, when designing a circuit, this continuous charging time should be kept suitable for the timing accuracy of the design. The corresponding process is as follows: at V... PK After keeping it unchanged, V A The voltage remains unchanged, and at this time, capacitor C2 continues to charge through resistor R14, V B The voltage level increases.

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

[0041] Generally, the design time accuracy is no greater than 100 nanoseconds. That is, from V... PK After remaining constant, capacitor C2 charges, causing V to... B The level is higher than V A This time period should not exceed the design value for time accuracy. For example, if R11=R12=R14=100K, R13=110K, C2=0.47pF, the estimated charging time of capacitor C2 is 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 acquire the half-wave time t2 (corresponding to) of the lightning strike waveform. Figure 2 (T2_OUT in the middle).

[0044] The half-wave time width (t2) sampling circuit consists of comparator A7, resistors R21, R22, R23, and R24, and capacitor C3. Resistors R24, R23, R21, and R22 are connected in series. The end of resistor R22 not connected to resistor R21 is connected to the full-wave time width sampling circuit, specifically to the positive terminal of comparator A5, and also to the negative terminal of comparator A1. The end of resistor R24 ​​not connected to resistor R23 is connected to the wavefront time width sampling circuit, specifically to the parallel connection of resistors R12 and R14, and also to the output terminal of comparator A4. The positive terminal of comparator A7 is connected between resistors R21 and R22, and the negative terminal is connected between resistors R23 and R24. One end of capacitor C3 is connected in parallel between resistors R23 and R21, and the other end is connected to the negative terminal of comparator A7.

[0045] In this system, the resistance values ​​of resistor R23 and R24 are equal. The first resistance value of resistor R22 is less than the second resistance value of resistor R21, and the difference between the first and second resistance values ​​is greater than or equal to a preset resistance difference threshold. The preset resistance difference threshold is set according to actual conditions, ensuring that the first resistance value of resistor R22 is significantly less than the second resistance value of resistor R21.

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

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

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

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

[0050] The working principle of the full-wave time-width circuit for lightning current can be understood as follows: The ratio of resistors R1 and R2 is used to make the negative input level V of comparator A5 equal to... L Sufficiently low (based on sampling precision), a fixed value. When V IN Greater than V L When the input is less than the design value, the comparator A5 outputs T_OUT at a high level until the input is less than the design value. This allows the full-wave time width t to be obtained.

[0051] Furthermore, the lightning strike sensor may also include a sampling control microcontroller. This microcontroller contains a control program. It is used to determine the shape of the lightning strike waveform and calculate the amount of lightning current by calculating and comparing the wavefront time t1, half-wave time t2, and full-wave time t, taking into account the inherent continuity characteristics of the current waveform.

[0052] The microcontroller and its sampling control principle can be understood as follows: Compared with time-sequential sampling, the circuit design of the lightning sensor provided in this embodiment of the invention only requires level judgment for sampling the wavefront time t1, half-wave time t2, and full-wave time t, and finally samples the PK_ADC as the amplitude. This not only accurately reflects the main parameters of the lightning current wave but also greatly simplifies the circuit design, achieving stability and high efficiency. The lightning waveform can be depicted from the PK_ADC value, the values ​​of t, t1, and t2, and the continuous characteristics of current changes.

[0053] This invention provides a lightning strike sensor. The sensor primarily consists of a lightning waveform signal follower, a 1.2 / 50μs lightning current amplitude sampling circuit, a wavefront time width sampling circuit, a half-wave time width sampling circuit, a full-wave time width sampling circuit, and a sampling control microcontroller and control program for recording the wavefront 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-purpose comparator circuit and an RC circuit, lightning current time parameter sampling only requires sampling the pulse width measurement time, effectively solving the high sampling frequency problem of time series digital sampling similar to oscilloscopes. This allows for the collection of the lightning parameters to be studied and implementation in practical application environments. Furthermore, the lightning strike sensor provided by this invention can prioritize time pulse width measurement during the sampling of the lightning current waveform period, without sampling the waveform current value during this period. This simplifies the sampling process, reduces the load on the sampling control system, and facilitates lightning parameter sampling at a better cost-effectiveness. Moreover, the comparator circuit and RC circuit can effectively resist electromagnetic interference in the lightning strike environment, thereby improving the sampling success rate.

[0054] For ease of understanding, the embodiments of the present invention are described below through specific examples.

[0055] In this example, based on Figure 2 The circuit schematic was used to establish an application circuit example.

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

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

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

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

[0061] According to the specific settings in this example Figure 3A schematic diagram of a 1.2 / 50μS sampling waveform obtained based on a lightning strike sensor is shown. Channel 1 corresponds to the wavefront time t1, and channel 2 corresponds to the half-wave time t2.

[0062] It is understood that other circuit examples constructed by adjusting circuit parameters according to the technical solution and related schematic diagrams provided by this invention are also within the protection scope of this invention. Based on the principles of this invention, more circuit examples of time sampling circuits can be deduced, which will not be elaborated 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, the embodiments of the present invention use "first" and "second" to distinguish and describe some technical features. "First" and "second" are only used to distinguish data and have no other special meaning. It is understood that the present invention does not impose any limitations on them.

[0064] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lightning strike sensor, characterized by, The lightning stroke sensor comprises a 1.2 / 50 μs lightning current amplitude sampling circuit, a time width sampling circuit based on a general comparator circuit and an RC circuit connected with 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; 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 a wave head time of the lightning stroke waveform; the half-wave time width sampling circuit is used for collecting a half-wave time of the lightning stroke waveform; and the full-wave time width sampling circuit is used for collecting a full-wave time of the lightning stroke waveform. 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 positive pole of the diode D1 is connected with the output end of the comparator A2; the negative pole of the diode D1 is connected with one end of the capacitor C1; the other end of the capacitor C1 is connected with the positive pole of the comparator A3; one end of the resistor R3 is connected with the negative pole and the output end of the comparator A2; and the other end of the resistor R3 is connected with the negative pole and the output end of the comparator A3. 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; one end of the resistor R11 is connected with one end of the resistor R13; the other end of the resistor R11 is connected with one end of the resistor R12 and the positive pole of the comparator A6; the other end of the resistor R13 is connected with one end of the resistor R14 and the negative pole of the comparator A6; the other end of the resistor R12 is connected with the other end of the resistor R14; and the capacitor C2 is connected with the resistor R13 in parallel. 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; one end of the resistor R22 not connected with the resistor R21 is connected to the full-wave time width sampling circuit; one end of the resistor R24 not connected with the resistor R23 is connected to the other end of the resistor R12; the positive pole of the comparator A7 is connected between the resistor R21 and the resistor R22; and the negative pole of the comparator A7 is connected between the resistor R23 and the resistor R24; the capacitor C3 is connected with the resistor R23 in parallel. A comparator A4 is further arranged between the output end of the comparator A3 and the parallel point of the resistor R12 and the resistor R14; the output end of the comparator A3 is connected with the positive pole of the comparator A4; and the negative pole and the output end of the comparator A4 are connected with the other end of the resistor R12. The full-wave time t width sampling circuit is composed of a comparator A5, a resistor R1 and a resistor R2; a positive electrode of the comparator A5 is connected with a lightning stroke waveform signal follower and the resistor R22, a negative electrode is connected with the resistor R1, an end of the R1 not connected with the negative electrode of the comparator A5 is connected with Vcc, an end of the resistor R2 is connected with the negative electrode of the comparator A5, and the other end of the resistor R2 is connected with VEE; The lightning stroke waveform signal follower is composed of a comparator A1, a positive electrode of the comparator A1 is connected with an input lightning stroke waveform signal, for absorbing transient impact of the lightning stroke waveform, buffering the lightning stroke waveform and reducing signal distortion; a negative electrode and an output end of the comparator A1 are connected with a positive electrode of the comparator A2, and the output end of the comparator A1 is also connected with the resistor R22 and a positive electrode of the comparator A5 respectively.

2. The lightning strike sensor of claim 1, wherein, A first ratio of the resistor R12 and the resistor R11 is greater than a second ratio of the resistor R14 and the resistor R13, and a difference between the first ratio and the second ratio is within a preset ratio difference range.

3. The lightning strike sensor of claim 1, wherein, A resistance value of the resistor R23 is equal to a resistance value of the resistor R24; a first resistance value of the resistor R22 is less than a second resistance value of the resistor R21, and a difference between the first resistance value and the second resistance value is greater than or equal to a preset resistance difference threshold value.

4. The lightning strike sensor according to any one of claims 1 to 3, characterized in that, The lightning stroke sensor further comprises a sampling control single-chip microcomputer, the sampling control single-chip microcomputer is provided with a control program; the sampling control single-chip microcomputer is used for judging a lightning stroke waveform shape and measuring a lightning current electric quantity by calculating and comparing the wave head time, the half-wave time and the full-wave time in combination with inherent continuity characteristics of a current waveform.

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