A lightning location system and method

Abstract

The application provides a thunder positioning system and method, and belongs to the technical field of thunder positioning. The system comprises a grating array acoustic demodulator and a composite optical cable. The composite optical cable comprises a communication optical cable and a chirped grating array composite in the communication optical cable. The grating array acoustic demodulator is used for emitting pulsed laser and transmitting the pulsed laser to the composite optical cable. The composite optical cable is used for generating reflected light based on the pulsed laser and returning the reflected light to the grating array acoustic demodulator. The grating array acoustic demodulator is further used for demodulating the reflected light, obtaining strain, and performing thunder positioning based on the strain. The application utilizes the characteristic that the chirped grating array has high spatial resolution, improves the spatial resolution of the thunder positioning system by three orders of magnitude, and further improves the thunder positioning precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lightning positioning, in particular to a lightning positioning system and method. BACKGROUND

[0002] Lightning positioning refers to a method and technology for determining the geographical position of lightning (and thus thunderstorm) according to sferics, which is mainly divided into multi-station positioning and single-station positioning. Lightning positioning is of great significance in weather forecasting, forest fire prevention, aviation, remote control of rockets and missiles, etc.

[0003] There are two existing lightning positioning technologies. One is to use the internal backup communication optical fiber of the communication optical cable as a sensing unit, and to establish a discharge conduction model based on the principle that lightning causes intense heat at the struck location. The sudden increase in distributed optical fiber temperature data or the enhancement of distributed vibration signals are analyzed to achieve lightning positioning. However, in actual application, due to the low spatial resolution of distributed optical fiber temperature (the spatial resolution is generally above 5 meters), it is difficult to effectively sense the small size (20 centimeter level) temperature rise caused by lightning. The other is a distributed optical fiber vibration detector. During measurement, lightning effects will disturb the entire optical cable, making it impossible to locate the vibration signal. In summary, the existing lightning positioning technology has the following technical problems: it cannot achieve high spatial resolution lightning positioning.

[0004] Therefore, it is necessary to provide a lightning positioning system and method to achieve high spatial resolution type positioning. SUMMARY

[0005] Therefore, it is necessary to provide a lightning positioning system and method to achieve high spatial resolution type positioning.

[0006] In one aspect, to solve the above technical problems, the present application provides a lightning positioning system, comprising: a grating array acoustic demodulator and a composite optical cable, wherein the composite optical cable comprises a communication optical cable and a chirped grating array composite in the communication optical cable.

[0007] The grating array acoustic demodulator is used to emit pulsed laser and transmit the pulsed laser to the composite optical cable.

[0008] The composite optical cable is used to generate reflected light based on the pulsed laser and return the reflected light to the grating array acoustic demodulator.

[0009] The grating array acoustic demodulator is further used to demodulate the reflected light, obtain strain, and perform lightning positioning based on the strain.

[0010] In a possible implementation, the lightning positioning system further comprises a compensator arranged between the grating array acoustic wave demodulator and the composite optical cable.

[0011] The compensator is configured to receive the pulsed laser, generate reference reflected light and probe laser, and send the reference reflected light to the grating array acoustic wave demodulator.

[0012] The composite optical cable is configured to generate reflected light based on the probe laser, and send the reflected light to the grating array acoustic wave demodulator via the compensator.

[0013] The grating array acoustic wave demodulator is further configured to determine static strain based on the reference reflected light and the reflected light, and perform lightning positioning based on the static strain.

[0014] In a possible implementation, the grating array acoustic wave demodulator comprises an intrinsic drift elimination unit and a lightning positioning unit.

[0015] The intrinsic drift elimination unit is configured to perform intrinsic drift elimination on the reflected light based on the reference reflected light, to obtain a target signal with a frequency of 0 Hz, the target signal being the static strain.

[0016] The lightning positioning unit is configured to determine a geographical position of lightning occurrence based on the static strain.

[0017] In a possible implementation, the lightning positioning unit comprises a lightning occurrence judgment subunit and a positioning subunit.

[0018] The lightning occurrence judgment subunit is configured to judge whether a strain change amount of the static strain is greater than a change amount threshold, and when greater, determine that lightning occurs.

[0019] The positioning subunit is configured to, when it is determined that lightning occurs, determine a geographical position of lightning occurrence based on position encoding of the chirped grating array.

[0020] In a possible implementation, the lightning positioning system further comprises an alarm instrument, which is configured to, when it is determined that lightning occurs, generate a lightning alarm signal, and display the geographical position.

[0021] In a possible implementation, the lightning positioning system further comprises an optical interface arranged between the grating array acoustic wave demodulator and the composite optical cable, and the optical interface is configured to separate a communication optical fiber signal and a sensing grating signal.

[0022] In a possible implementation, the chirped grating array comprises a plurality of chirped gratings, and a center wavelength of the chirped gratings is 1550.12 nm.

[0023] In a possible implementation, the pitch between two adjacent chirped gratings is 5 m, and the reflection ratio of the chirped gratings is 0.01%.

[0024] In a possible implementation, the demodulation algorithm of the grating array acoustic wave demodulator is a 3*3 interference demodulation algorithm.

[0025] In another aspect, the present application also provides a lightning positioning method, which is applicable to the lightning positioning system in any of the possible implementations described above, and the method comprises:

[0026] controlling the grating array acoustic wave demodulator to emit pulsed laser and transmit the pulsed laser to the composite optical cable;

[0027] controlling the composite optical cable to generate reflected light based on the pulsed laser and return the reflected light to the grating array acoustic wave demodulator;

[0028] controlling the grating array acoustic wave demodulator to demodulate the reflected light, obtain strain, and perform lightning positioning based on the strain.

[0029] The lightning positioning system provided by the present application positions lightning by setting a communication optical cable and a chirped grating array composite in the communication optical cable, utilizes the characteristic that the chirped grating array has high spatial resolution, improves the spatial resolution of the lightning positioning system by three orders of magnitude, and thus improves the lightning positioning precision.

[0030] Further, the grating array acoustic wave demodulator in the present application has physical positioning capability and can realize accurate positioning of lightning. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0032] Figure 1 An embodiment structure diagram of the lightning positioning system provided by the present application;

[0033] Figure 2 An embodiment diagram of the vibration response signal with intrinsic drift provided by the present application;

[0034] Figure 3 An embodiment diagram of the vibration response signal without intrinsic drift provided by the present application;

[0035] Figure 4 An embodiment structure schematic diagram of the grating array acoustic wave demodulator provided by the present application is shown in the figure;

[0036] Figure 5 An embodiment flow schematic diagram of the lightning positioning method provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0038] It should be understood that the schematic drawings are not drawn to scale. The flowcharts used in the present application show the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowcharts can not be implemented in sequence, and the steps without logical context relationship can be reversed in sequence or implemented simultaneously. In addition, one or more other operations can be added to the flowcharts or removed from the flowcharts by those skilled in the art under the guidance of the content of the present application. Some block diagrams shown in the drawings are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.

[0039] Reference to "an embodiment" in this text means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily mutually exclusive or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0040] The present application provides a lightning positioning system and method, which are described below respectively.

[0041] Figure 1 An embodiment structure schematic diagram of the lightning positioning system provided by the present application is shown in the figure, Figure 1 As shown in the figure, the lightning positioning system 10 comprises a grating array acoustic wave demodulator 100 and a composite optical cable 200, the composite optical cable 200 comprising a communication optical cable and a chirped grating array composite in the communication optical cable;

[0042] The grating array acoustic demodulator 100 is used for emitting pulsed laser and transmitting the pulsed laser to the composite optical cable 200.

[0043] The composite optical cable 200 is used for generating reflected light based on the pulsed laser and returning the reflected light to the grating array acoustic demodulator 100.

[0044] The grating array acoustic demodulator 100 is also used for demodulating the reflected light, obtaining strain, and performing lightning positioning based on the strain.

[0045] The communication optical cable can be an OPGW (Optical fiber composite overhead ground wire, OPGW) optical cable or an OPPC (Optical Phase Conductor, OPPC) optical cable.

[0046] The OPGW optical cable is a kind of optical fiber fixed optical cable, which has the functions of optical fiber transmission and power transmission. The optical fiber fixed optical cable (OPGW) represents that the optical cable is generated at the center of a layer of electrically isolated aluminum wire, which is commonly used in power transmission lines and can transmit a large amount of information through fiber optical cables. The OPGW optical cable uses high-tech optical fiber communication technology and can provide reliable communication transmission on the power transmission line.

[0047] The OPPC is a new type of special optical cable for power communication systems, which is an optical cable that combines optical fiber units in the conductor in the traditional phase line structure. It makes full use of the line resources of the power system, especially the power distribution network system, to avoid conflicts with the outside world in terms of frequency resources, route coordination, electromagnetic compatibility, etc., so as to have the dual functions of transmitting electric energy and communication.

[0048] The lightning positioning principle of the lightning positioning system 10 provided in the embodiment of the present application is that when lightning occurs, the lightning will cause a transient impact on the OPGW / OPPC optical cable, causing a strain effect on the local optical cable. By quickly monitoring this strain effect, the lightning can be quickly positioned.

[0049] Compared with the prior art, the lightning positioning system 10 provided in the embodiment of the present application positions lightning by setting a communication optical cable and a chirped grating array composite in the communication optical cable, utilizes the characteristic that the chirped grating array has high spatial resolution, improves the spatial resolution of the lightning positioning system 10 by three orders of magnitude, and further improves the lightning positioning accuracy.

[0050] Further, the grating array acoustic demodulator 100 in the embodiment of the present application has physical positioning capability and can realize accurate positioning of lightning.

[0051] As the grating array acoustic demodulator 100 demodulates the reflected light, there is intrinsic drift, as shown in Figure 2 It can be seen that the amplitude of the vibration response signal gradually increases with the increase of the frequency, and the influence of the uneliminated intrinsic drift on the lightning positioning result, in some embodiments of the present application, as shown in Figure 1 The lightning positioning system 10 further comprises a compensator 300 arranged between the grating array acoustic demodulator 100 and the composite optical cable 200;

[0052] The compensator 300 is used to receive pulsed laser, generate reference reflected light and probe laser, and send the reference reflected light to the grating array acoustic demodulator 100;

[0053] The composite optical cable 200 is used to generate reflected light based on the probe laser, and send the reflected light to the grating array acoustic demodulator 100 via the compensator;

[0054] The grating array acoustic demodulator 100 is further used to determine the static strain based on the reference reflected light and the reflected light, and perform lightning positioning based on the static strain.

[0055] The present application eliminates the intrinsic drift of the reflected light by the reference reflected light generated by the compensator 300, which can avoid the adverse effects of the intrinsic drift on the lightning positioning result, and further ensures the accuracy of the lightning positioning result.

[0056] In specific embodiments of the present application, Figure 3 To eliminate the intrinsic drift of the reflected light, the reference reflected light is generated by Figure 3 It can be seen that: with the increase of the frequency, the intrinsic drift does not occur, and the vibration response signal is only related to the external lightning signal, which ensures the accuracy of the lightning positioning.

[0057] In specific embodiments of the present application, as shown in Figure 4 The grating array acoustic demodulator 100 comprises an intrinsic drift elimination unit 110 and a lightning positioning unit 120;

[0058] The intrinsic drift elimination unit 110 is used to eliminate the intrinsic drift of the reflected light based on the reference reflected light, to obtain a target signal with a frequency of 0Hz, and the target signal is a static strain;

[0059] The lightning positioning unit 120 is used to determine the geographical position where the lightning occurs based on the static strain.

[0060] The present application can make the static strain effectively reflect the development of lightning by taking the target signal with a frequency of 0Hz as the static strain, eliminate the influence of external interference such as wind, rain and the like, and further improve the positioning accuracy of the lightning positioning system 10.

[0061] In specific embodiments of the present application, as shown inFigure 4 As shown in the figure, the lightning positioning unit 120 comprises a lightning occurrence judgment subunit 121 and a positioning subunit 122;

[0062] The lightning occurrence judgment subunit 121 is used for judging whether the strain change amount of the static strain is greater than the change amount threshold value, and when it is greater, it is determined that lightning occurs.

[0063] The positioning subunit 122 is used for determining the geographical position where the lightning occurs based on the position coding of the chirped grating array when it is determined that lightning occurs.

[0064] In the embodiment of the application, the lightning occurrence judgment subunit 121 judges the occurrence of lightning through the strain change amount of the static strain instead of directly judging the static strain, thereby further eliminating the influence of inherent interference terms from the outside and further improving the judgment accuracy of whether lightning occurs.

[0065] Specifically, the positioning principle of the positioning subunit 122 is that each chirped grating in the chirped grating array has a unique position coding, and when it is determined that lightning occurs, the geographical position where the lightning occurs can be determined based on the position coding corresponding to the reflected light when lightning occurs, and the positioning efficiency is high.

[0066] In order to timely remind the staff of the occurrence of lightning and the specific geographical position when lightning occurs, in some embodiments of the application, as shown in the figure, Figure 1 As shown in the figure, the lightning positioning system 10 further comprises an alarm instrument 400, and the alarm instrument 400 is used for generating a lightning alarm signal when it is determined that lightning occurs, and displaying the geographical position.

[0067] The embodiment of the application not only alarms to prompt that lightning has occurred, but also displays the geographical position on the alarm instrument 400, thereby providing data support for subsequent processing and improving the timeliness and efficiency of processing the lightning position.

[0068] Since the composite optical cable 200 is used to simultaneously transmit communication optical fiber signals and sensing grating signals, and the grating array acoustic demodulator 100 only needs to process the sensing grating signals, in order to realize accurate and stable transmission of the two types of signals, i.e., the communication optical fiber signals and the sensing grating signals, in some embodiments of the application, as shown in the figure, Figure 1 As shown in the figure, the lightning positioning system 10 further comprises an optical interface 500 arranged between the grating array acoustic demodulator 100 and the composite optical cable 200, and the optical interface 500 is used for separating the communication optical fiber signals and the sensing grating signals.

[0069] In the embodiment of the application, the optical interface 500 is arranged to separate the communication optical fiber signals and the sensing grating signals, so that the communication optical fiber signals and the sensing grating signals can be used specifically, and the mutual influence is avoided, thereby improving the communication capability of the composite optical cable 200 on the premise of ensuring accurate lightning positioning.

[0070] In the specific embodiment of the present application, the chirped grating array comprises a plurality of chirped gratings, the center wavelength of the chirped gratings is 1550.12 nm, and the interval between two adjacent chirped gratings is 2 m.

[0071] That is, the spatial resolution of the lightning positioning system 10 is 2 m.

[0072] Specifically, the chirped grating array can obtain 2 m / 1550.12 nm=1290222 wavelengths within 2 m, and by analyzing the 1290222 wavelengths, it can be determined whether lightning occurs and its geographic location.

[0073] In the specific embodiment of the present application, the reflection ratio of the chirped grating is 0.01%. That is, the sensing signal of the communication optical fiber is 1000 times stronger, and the positioning accuracy of the lightning positioning through the chirped grating is further realized.

[0074] In some embodiments of the present application, the demodulation algorithm of the grating array acoustic demodulator is a 3*3 interference demodulation algorithm.

[0075] Specifically, the 3*3 interference demodulation algorithm is:

[0076]

[0077] In the formula, I1 is the first grating signal value; I2 is the second grating signal value; I3 is the third grating signal value; I0 is the signal value of the pulsed laser; is the phase at time t.

[0078] Through the above-mentioned ternary cubic equation, the current phase carrying the change of the optical path difference (that is, the physical distance between gratings) of the chirped grating array combined into the OPGW / OPPC can be demodulated. By detecting the change of the optical path difference of the chirped grating array combined into the OPGW / OPPC, the change amount of the physical distance of the grating (static strain) can be calculated.

[0079] In summary, when lightning strikes the chirped grating array combined into the OPGW / OPPC, the lightning positioning system 10 proposed in the embodiments of the present application forms a static strain change to the chirped grating array combined into the OPGW / OPPC, causing a change in the optical path difference; the grating array acoustic demodulator used in the embodiments of the present application adopts internal self-compensation, which can convert the phase change of the interference demodulation through the change of the optical path difference, and then realize the static strain value measurement through the phase compensation algorithm, so as to reflect the development of lightning and realize the accurate positioning of lightning.

[0080] In another aspect, the present application also provides a lightning positioning method, which is applicable to the lightning positioning system in any of the above embodiments, such as Figure 5 As shown in the figure, the lightning positioning method comprises:

[0081] S501, controlling the grating array acoustic demodulator 100 to emit pulsed laser and transmit the pulsed laser to the composite optical cable 200;

[0082] S502, controlling the composite optical cable 200 to generate reflected light based on the pulsed laser and return the reflected light to the grating array acoustic demodulator 100;

[0083] S503, controlling the grating array acoustic demodulator 100 to demodulate the reflected light, obtain strain, and perform lightning positioning based on the strain.

[0084] It should be noted that: in order to eliminate the influence of intrinsic drift of the grating array acoustic demodulator, in some embodiments of the present application, before step S502, it further comprises:

[0085] receiving pulsed laser, generating reference reflected light and probe laser, and sending the reference reflected light to the grating array acoustic demodulator;

[0086] Then step S502 can be:

[0087] controlling the composite optical cable to generate reflected light based on the probe laser, and sending the reflected light to the grating array acoustic demodulator;

[0088] Then step S503 can be:

[0089] controlling the grating array acoustic demodulator to further determine static strain based on the reference reflected light and the reflected light, and performing lightning positioning based on the static strain.

[0090] The embodiment of the present application can eliminate the intrinsic drift of the reflected light by the reference reflected light, which can avoid the adverse effects of intrinsic drift on the lightning positioning result, and further ensure the accuracy of the lightning positioning result.

[0091] The lightning positioning method provided by the above embodiment can realize the technical solutions described in the above lightning positioning system embodiments, and the principles of the specific implementation of the above steps can be referred to the corresponding contents in the above lightning positioning system embodiments, which will not be described here.

[0092] The above describes in detail the lightning positioning system and method provided by the present application. The principles and implementation manners of the present application are described by using specific examples. The above description of the examples is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, the specific implementation manners and application ranges will be changed according to the idea of the present application. In summary, the content of the present description should not be understood as a limitation of the present application.

Claims

1. A lightning location system, characterized in that, include: A grating array acoustic demodulator and a composite optical cable, the composite optical cable including a communication optical cable and a chirped grating array composited in the communication optical cable; The grating array acoustic demodulator is used to emit pulsed laser and transmit the pulsed laser to the composite optical cable; The composite optical cable is used to generate reflected light based on the pulsed laser and return the reflected light to the grating array acoustic demodulator. The grating array acoustic demodulator is also used to demodulate the reflected light to obtain strain, and to perform lightning location based on the strain. The lightning location system further includes a compensator disposed between the grating array acoustic demodulator and the composite optical cable. The compensator is used to receive the pulsed laser, generate a reference reflected light and a probe laser, and send the reference reflected light to the grating array acoustic demodulator; The composite optical cable is used to generate reflected light based on the probe laser, and to send the reflected light to the grating array acoustic demodulator via the compensator; The grating array acoustic demodulator is also used to determine static strain based on the reference reflected light and the reflected light, and to perform lightning location based on the static strain; The grating array acoustic demodulator includes an intrinsic drift elimination unit and a lightning location unit. The intrinsic drift elimination unit is used to perform intrinsic drift elimination on the reflected light based on the reference reflected light to obtain a target signal with a frequency of 0Hz, and the target signal is the static strain. The lightning location unit is used to determine the geographical location of the lightning strike based on the static strain. The lightning location unit includes a lightning occurrence judgment subunit and a location subunit; The lightning occurrence determination subunit is used to determine whether the strain change of the static strain is greater than the change threshold. If it is greater, it is determined that lightning has occurred. The positioning subunit is used to determine the geographical location of the lightning strike based on the position encoding of the chirped grating array when it is determined that lightning has occurred.

2. The lightning location system according to claim 1, characterized in that, The lightning location system also includes an alarm instrument, which generates a lightning alarm signal and displays the geographical location when lightning is detected.

3. The lightning location system according to claim 1, characterized in that, The lightning location system also includes an optical interface disposed between the grating array acoustic demodulator and the composite optical cable, the optical interface being used to separate the communication fiber optic signal and the sensing grating signal.

4. The lightning location system according to any one of claims 1-3, characterized in that, The chirped grating array includes multiple chirped gratings, the center wavelength of which is 1550.12 nm.

5. The lightning location system according to claim 4, characterized in that, The spacing between two adjacent chirped gratings is 5m, and the reflectance of the chirped grating is 0.01%.

6. The lightning location system according to claim 1, characterized in that, The demodulation algorithm of the grating array acoustic demodulator is a 3×3 interferometric demodulation algorithm.

7. A method for locating lightning strikes, characterized in that, The method applicable to the lightning location system according to any one of claims 1-6 includes: The grating array acoustic demodulator is controlled to emit pulsed laser light, and the pulsed laser light is transmitted to the composite optical cable; The composite optical cable is controlled to generate reflected light based on the pulsed laser and return the reflected light to the grating array acoustic demodulator. The grating array acoustic demodulator is controlled to demodulate the reflected light to obtain strain, and lightning location is performed based on the strain.

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