Lightning stroke detection method and device for adaptive polarization controller

Abstract

The invention relates to the technical field of power transmission line monitoring, in particular to a lightning stroke detection method and device for a self-adaptive polarization controller. According to the invention, the polarization state of the input optical signal is compensated in real time through the self-adaptive polarization controller existing at the receiving and transmitting end of the optical cable line, and the phase shift amount change signal of each phase shifter in the self-adaptive polarization controller is subjected to high-pass filtering processing, so that the occurrence of the lightning stroke event is judged. A timestamp related to occurrence of a lightning stroke event is obtained, and the occurrence position of the lightning stroke event is obtained according to the timestamp. According to the invention, an original framework of an original communication system is not changed, a device does not need to be reset for lightning stroke point positioning, and accurate positioning of a lightning stroke event can be realized while polarization compensation is realized, so that re-laying of a lightning stroke positioning device is avoided, multiplexing of equipment is realized, and application cost is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of power transmission line monitoring technology, and in particular to a lightning strike detection method and device using an adaptive polarization controller. Background Technology

[0002] Optical fiber composite over ground wire (OPGW) is mainly installed along 110kV and above overhead lines, serving the dual functions of an overhead ground wire and an optical fiber communication line. As of the end of 2021, the total length of OPGW optical cables was approximately 993,100 kilometers, making it the most important physical medium for carrying the backbone communication network of the power grid. Unlike operator and submarine optical cable systems, OPGW is installed overhead along transmission lines. Currently, with the rapid development of ultra-high voltage power transmission, inter-regional power transmission networks, and the energy internet, transmission distances are long, the lines cross remote, sparsely populated, and harsh environments, especially in some central and western regions where it is difficult to set up communication relay stations along the lines. The number of ultra-long-distance optical fiber communication scenarios without relay stations is increasing, often requiring communication segments of over 300km, posing a significant challenge to the supporting optical fiber communication systems: long-distance, high-capacity OPGW overhead optical cable communication systems are more susceptible to optical damage such as rapid polarization rotation and polarization mode dispersion of optical signals. Coherent detection in communication systems requires that the polarization states of the signal light and the local oscillator light be consistent. Random fluctuations in the polarization state of the local oscillator light can cause carrier fading, leading to coherent reception failure. Therefore, an adaptive polarization controller needs to be installed before the receiver to stabilize the polarization state of the local oscillator light.

[0003] Meanwhile, the lines span a wide area and the environment is complex. Severe weather such as lightning can damage optical cables, causing a decline in communication quality or even interruption, which seriously threatens the reliability of the power communication system.

[0004] Most existing technologies for lightning strike monitoring are based on fiber optic sensing. Since OPGW (Optical Wire Roofing Cable) is susceptible to rapid changes in polarization state due to lightning strikes and other factors, polarization stabilization devices are needed to restore and compensate for the polarization state. However, current fiber optic sensing solutions can only locate the lightning strike point and cannot simultaneously compensate for polarization state. Furthermore, they require additional sensing equipment, such as pulse generators, leading to high costs.

[0005] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0006] The technical problem to be solved by this invention is how to simultaneously achieve polarization compensation and accurate positioning of lightning strike points in OPGW.

[0007] The present invention adopts the following technical solution: In a first aspect, a lightning strike detection method based on an adaptive polarization controller is provided, wherein transceivers are respectively installed at both ends of an optical cable line, and the optical cable line integrates an adaptive polarization controller. The method includes: The polarization state of the input optical signal is compensated in real time by the adaptive polarization controller, and the phase shift change signal of each phase shifter in the adaptive polarization controller is monitored in real time. The phase shift change signal is subjected to high-pass filtering to obtain high-frequency disturbance components. When the high-frequency disturbance components exceed a preset threshold, it is determined that a lightning strike event has occurred. Obtain the timestamp associated with the lightning strike, and determine the location of the lightning strike based on the timestamp.

[0008] Preferably, the real-time compensation of the polarization state of the input optical signal through the adaptive polarization controller specifically includes: Obtain the optical power at the feedback port of the adaptive polarization controller; The control signal for adjusting the phase modulation amount of the phase shifter in the adaptive polarization controller is obtained based on the optical power of the feedback port. The control signal is applied to the phase shifter to change the phase modulation amount of the phase shifter; By changing the phase modulation amount of the phase shifter to minimize the optical power at the feedback port of the adaptive polarization controller, real-time compensation of the polarization state of the input optical signal can be achieved.

[0009] Preferably, obtaining the timestamp related to the occurrence of the lightning strike specifically includes: The transceiver at the first end detects the polarization disturbance caused by the lightning strike, generates the first trigger signal, and records the first time point; After the transceiver at the second end detects the polarization disturbance, it generates a second trigger signal and transmits the second trigger signal to the transceiver at the first end. After the transceiver at the first end detects the second trigger signal, it records a second time point. The timestamps related to the occurrence of the lightning strike are obtained based on the first time point corresponding to the first trigger signal and the second time point corresponding to the second trigger signal.

[0010] Preferably, obtaining the location of the lightning strike based on the timestamp specifically includes: The time delay difference between the first trigger signal and the second trigger signal in the transceiver at the first end is obtained based on the first time point and the second time point; the location of the lightning strike event is obtained based on the time delay difference.

[0011] Preferably, determining the location of the lightning strike based on the time delay difference specifically includes: The time delay difference is obtained by subtracting the second time point from the first time point; The distance 'a' between the location of the lightning strike and the transceiver at the first end is calculated using the formula a=L-(v×ΔT) / 2 to obtain the location of the lightning strike. Where L is the total length of the optical fiber between the transceiver at the first end and the transceiver at the second end, v is the speed of light in the optical fiber, and ΔT is the time delay difference.

[0012] Preferably, the step of performing high-pass filtering on the phase shift change signal to obtain high-frequency disturbance components specifically includes: The phase shift change signal is input to a high-pass filter to extract the high-frequency disturbance component in the phase shift change signal; The cutoff frequency of the high-pass filter is set to be higher than the signal change frequency when the adaptive polarization controller compensates for normal polarization disturbances, and lower than the signal change frequency corresponding to polarization disturbances caused by lightning strikes.

[0013] Preferably, the cutoff frequency of the high-pass filter is set to 100kHz or higher.

[0014] Preferably, when the adaptive polarization controller includes a first phase shifter and a second phase shifter, the transfer matrix of the adaptive polarization controller is: ; in, The complex amplitude of the optical field at the master port of the adaptive polarization controller. The complex amplitude of the optical field at the feedback port of the adaptive polarization controller. The horizontal polarization component of the input optical signal. The vertical polarization component of the input optical signal. This is the phase modulation amount of the first phase shifter. This is the phase modulation amount of the second phase shifter.

[0015] Secondly, a lightning strike detection device for an adaptive polarization controller is provided, the adaptive polarization controller lightning strike detection device comprising: a processor and a memory for storing processor-executable instructions; The processor is configured to execute the lightning strike detection method of the adaptive polarization controller.

[0016] Thirdly, a non-volatile computer storage medium is provided, the computer storage medium storing computer-executable instructions, which are executed by one or more processors to perform the lightning strike detection method of the adaptive polarization controller described in the first aspect.

[0017] Fourthly, a chip is provided, comprising: a processor and an interface for calling and running a computer program stored in a memory to execute a lightning strike detection method of an adaptive polarization controller as described in the first aspect.

[0018] Fifthly, a computer program product containing instructions is provided, which, when executed on a computer or processor, causes the computer or processor to perform a lightning strike detection method for an adaptive polarization controller as described in the first to fourth aspects and any one of them.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes an existing adaptive polarization controller at the optical cable transceiver end to perform real-time compensation for the polarization state of the input optical signal. By high-pass filtering the phase shift changes of each phase shifter in the adaptive polarization controller, the occurrence of a lightning strike can be determined. The location of the lightning strike is then determined based on the timestamp associated with the lightning strike. This invention does not alter the original architecture of the communication system, eliminates the need for reconfigured lightning strike location devices, and achieves precise lightning strike location simultaneously with polarization compensation. This avoids the need to re-lay lightning strike location equipment, enabling equipment reuse and significantly reducing application costs. Attached Figure Description

[0020] 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.

[0021] Figure 1 This is a schematic flowchart of a lightning strike detection method based on an adaptive polarization controller provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of an adaptive polarization controller provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the working process of an adaptive polarization controller provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a first-order passive high-pass filter provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of a process for obtaining a timestamp provided by an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure in which a lightning strike event occurs in an optical cable line, provided by an embodiment of the present invention; Figure 7This is a schematic diagram of a lightning strike detection device based on an adaptive polarization controller provided in an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as openly inclusive, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples; that is, although they may be incorporated into embodiments or examples using the above terms for reasons such as order and position, it does not limit them to be incorporated in combination by a single embodiment or example.

[0024] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more. Furthermore, for example, the description may use the prefix "A" or "B" to describe the same type of nouns as two independent entities. In this case, the corresponding features defined with "A" and "B" are used only to distinguish between similar entities and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features.

[0025] In describing some embodiments, the terms "coupled," "coupled," and "connected," and their derivative expressions, may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact with each other. Similarly, the term "coupled" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact. However, the terms "connected" or "coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other, such as "optical coupling," "wireless connection," etc. The embodiments disclosed herein are not necessarily limited to the scope of this invention.

[0026] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] Example 1: To address the problems of existing technologies, this embodiment proposes a lightning strike detection method based on an adaptive polarization controller. Firstly, transceivers need to be installed at both ends of the optical cable line. The optical cable line integrates an adaptive polarization controller. In one embodiment, such as... Figure 1 As shown, the lightning strike detection method based on an adaptive polarization controller specifically includes: Step 101: The polarization state of the input optical signal is compensated in real time by the adaptive polarization controller, and the phase shift change signal of each phase shifter in the adaptive polarization controller is monitored in real time.

[0028] The adaptive polarization controller is a closed-loop feedback system containing one or more phase shifters. These phase shifters change their optical phase according to the received control signal, thereby dynamically adjusting the polarization state of the optical signal. The control algorithm aims to minimize the optical power at the feedback port, continuously calculating and outputting the optimal control signal to the phase shifters to counteract slow polarization disturbances caused by the external environment.

[0029] Simultaneously, the system acquires and records the control signal driving the phase shifter in real time. The control signal is directly related to the phase change of the phase shifter; therefore, monitoring this control signal is equivalent to monitoring the polarization compensation process. Under normal conditions, the control signal changes slowly; when there is a sudden disturbance, the control signal changes drastically. That is, when the polarization state is locked, the phase shift of the phase shifter in the adaptive polarization controller continuously changes to compensate for the constantly changing input polarization state. Therefore, the rate of change of the input polarization state can be determined by the rate of change of the phase shift. If the rate of change of the input polarization state is very slow, the phase shift of the polarization controller remains slowly changing or stable; if the input polarization state changes drastically, the phase shift also changes drastically to offset the external changes.

[0030] Step 102: Perform high-pass filtering on the phase shift change signal to obtain high-frequency disturbance components. When the high-frequency disturbance components exceed a preset threshold, it is determined that a lightning strike event has occurred.

[0031] The process begins by passing the phase shift change signal through a high-pass filter. The cutoff frequency of this high-pass filter can be specially set to effectively filter out low-frequency, slowly changing signals caused by normal environmental changes, while retaining drastic, rapid, high-frequency abrupt changes caused by sudden events such as lightning strikes.

[0032] The output signal of the high-pass filter is then fed into a threshold comparator. When the amplitude of the filtered signal exceeds a preset threshold, the threshold comparator is triggered, and a valid lightning strike event is determined to have occurred. In one embodiment, the preset threshold can be set according to the system noise level to prevent false alarms.

[0033] Step 103: Obtain the timestamp related to the occurrence of the lightning strike, and determine the location of the lightning strike based on the timestamp.

[0034] Once a lightning strike event is identified, its timestamp is accurately recorded. The lightning strike event location mechanism proposed in this embodiment relies on measuring the different times when the disturbance signal generated by the same lightning strike event is transmitted to the transceivers at both ends of the optical cable line, which is the timestamp.

[0035] The polarization disturbance generated by a lightning strike propagates simultaneously to both ends of the optical cable line (i.e., via optical fiber) (divided into the measuring end and the receiving end). The measuring end detects the directly transmitted disturbance for the first time and records the first time point. Upon detecting the disturbance, the receiving end immediately generates and sends back a specific response optical signal. When the measuring end detects this response optical signal again, it records the second time point. By calculating the time delay difference between the second and first time points—which represents the total time for the optical signal to travel from the lightning strike point to the receiving end and back to the measuring end—and combining this with the speed of light in the optical fiber, the precise distance between the lightning strike point and the measuring end can be calculated, thus enabling fault location.

[0036] This embodiment utilizes an existing adaptive polarization controller at the optical cable transceiver end to perform real-time compensation for the polarization state of the input optical signal. By high-pass filtering the phase shift changes of each phase shifter in the adaptive polarization controller, the occurrence of a lightning strike is determined. The location of the lightning strike is then determined based on the timestamp associated with the lightning strike. This embodiment does not alter the original architecture of the communication system and eliminates the need to reconfigure lightning strike location equipment. It achieves precise lightning strike location while simultaneously performing polarization compensation, thus avoiding the need to re-lay lightning strike location devices, enabling equipment reuse, and significantly reducing application costs.

[0037] In one embodiment, such as Figure 2 As shown, taking the adaptive polarization controller comprising at least two phase shifters, a polarization beam splitter (PRS), a detector, a 3-dB coupler, and a driving circuit as an example, as follows... Figure 3 As shown, the real-time compensation of the polarization state of the input optical signal through the adaptive polarization controller specifically includes: Step 1011: Obtain the optical power at the feedback port of the adaptive polarization controller.

[0038] The input optical signal is split into a main output signal and a feedback optical signal by a polarization beamsplitter. The main output optical signal, containing most of the optical power, is directed to the main output port for use in subsequent communication systems (such as coherent receivers). The feedback optical signal, containing a small portion of the optical power, is separated and directed to the feedback port. A detector detects the feedback optical signal and linearly converts its optical power into a current or voltage signal.

[0039] The optical power at the feedback port directly reflects the degree of deviation between the polarization state of the current output light of the adaptive polarization controller and the ideal target polarization state. The smaller the optical power at the feedback port, the closer the polarization state of the output light is to the target value, and the better the adaptive polarization controller is performing.

[0040] Step 1012: Obtain a control signal for adjusting the phase modulation amount of the phase shifter in the adaptive polarization controller based on the optical power of the feedback port.

[0041] The driving circuit reads the electrical signal from the detector through an analog-to-digital converter. The value of this signal represents the current feedback optical power Pfb.

[0042] In one embodiment, an optimization algorithm (such as gradient descent, perturbation algorithm, etc.) runs inside the driving circuit. The optimization objective of this algorithm is to minimize the feedback optical power Pfb. Based on the current value of the feedback optical power Pfb and historical data, the algorithm calculates and makes decisions, outputting a new set of control voltage values ​​(i.e., control signals) for adjusting each phase shifter. The core of this algorithm is to determine whether to increase or decrease the control voltage of each phase shifter to reduce the feedback optical power Pfb, and by how much.

[0043] Step 1013: Apply the control signal to the phase shifter to change the phase modulation amount of the phase shifter.

[0044] The drive circuit converts the calculated control signal into an analog voltage signal using a digital-to-analog converter. This analog voltage signal is amplified and filtered to a level that can effectively drive the phase shifters. The amplified voltage signal is then applied to each phase shifter within the adaptive polarization controller to change the phase modulation amount of the phase shifters.

[0045] Step 1014: By changing the phase modulation amount of the phase shifter, the optical power at the feedback port of the adaptive polarization controller is minimized, so as to achieve real-time compensation for the polarization state of the input optical signal.

[0046] As the phase modulation amount of the phase shifter changes, the optical path characteristics inside the adaptive polarization controller immediately change, causing a change in the polarization state of the output and feedback optical signals. The feedback optical power Pfb changes accordingly. Returning to step 1011, the new feedback optical power Pfb is obtained again, and steps 1012 and 1013 are repeated to generate and apply new control signals to each phase shifter to further reduce the feedback optical power Pfb.

[0047] The entire loop runs continuously at extremely high speeds (typically on the order of microseconds or milliseconds) to track any slow drift in the polarization state of the input light in real time, thereby enabling adaptive real-time compensation for the polarization state of the input optical signal.

[0048] In one embodiment, the principle of the above process is explained as follows: For a single phase shifter, the control algorithm increases or decreases its phase shift modulation amount, measures the feedback optical power Pfb at the feedback port of the adaptive polarization controller, and changes the direction of the phase shift modulation amount based on the change in the feedback optical power Pfb. Taking a two-stage phase shifter as an example, the phase shifter can be described using a Jones matrix: ; The Jones matrix expression for a 3-dB coupler is: ; When the adaptive polarization controller includes a first phase shifter and a second phase shifter, the transfer matrix of the adaptive polarization controller is: ; in, The complex amplitude of the optical field at the master port of the adaptive polarization controller. The complex amplitude of the optical field at the feedback port of the adaptive polarization controller. The horizontal polarization component of the input optical signal. The vertical polarization component of the input optical signal. This is the phase modulation amount of the first phase shifter. This is the phase modulation amount of the second phase shifter.

[0049] Based on the above transfer matrix, we obtain: ; Obviously, for any input polarization state, | |It's about and Periodic function, equation The solution for =0 is: ; Where m and n are both integers. Therefore, for any input optical signal polarization state, a set of polarization states can be found through optimization algorithms. and This ensures that the optical power at the feedback port is zero, and both polarization components at the incident end are completely converted to TE mode and output from the main output port. By monitoring the optical power at the feedback port in real time and adjusting the voltages of the two phase shifters to minimize the optical power at the feedback port (minimum power is 0), real-time feedback control and stable adjustment of the input polarization state can be achieved. (Optical field at the feedback port) It is the input light field , and two control phases and The function. For any given input polarization state ( , ), find a set of phase values ​​( , ), making =0 (meaning the feedback optical power is zero). Once this set of values ​​is found and continuously tracked, it means the main output port... The polarization state was perfectly stabilized. (Refer to...) Figure 2 The four-stage phase shifter architecture shown is based on the same principle as the two-stage architecture, and will not be explained in detail here.

[0050] In optical fiber lines, due to the inherent weak birefringence of the fiber, the polarization state changes slowly and continuously. To compensate for this, the phase shift of the adaptive polarization controller also changes slowly. However, when factors such as lightning strikes cause drastic changes in the input polarization state, the phase shift also changes drastically. Therefore, a high-pass filter can be added to detect the high-frequency components in the phase shift change. This embodiment uses, for example... Figure 4 Taking the first-order passive high-pass filter shown as an example, Vin is the input and Vout is the output. The high-pass filtering process performed on the phase shift change signal to obtain the high-frequency disturbance component specifically includes: The phase shift change signal is input to a high-pass filter to extract the high-frequency disturbance component in the phase shift change signal; wherein, the cutoff frequency of the high-pass filter is set to be higher than the signal change frequency when the adaptive polarization controller compensates for normal polarization disturbance, and lower than the signal change frequency corresponding to the polarization disturbance caused by a lightning strike event. Specifically, the cutoff frequency of the high-pass filter is set to be above 100kHz.

[0051] In one embodiment, high-pass filtering is performed on the phase shift change signal to obtain high-frequency disturbance components. The core of this method is to accurately separate the lightning-related signal from the mixed signal of normal polarization disturbance and lightning-induced polarization disturbance. Specifically, the mixed signal is input into a high-pass filter, and the high-frequency components are extracted by utilizing the characteristic of the high-pass filter that only allows high-frequency signals to pass through and attenuates low-frequency signals.

[0052] The key to ensuring the effectiveness of filtering lies in setting the cutoff frequency. It needs to be positioned between the signal change frequency when the adaptive polarization controller compensates for normal polarization disturbances and the signal change frequency corresponding to polarization disturbances caused by lightning strikes. On the one hand, the cutoff frequency must be higher than the signal change frequency of normal disturbances to completely filter out low-frequency normal disturbances caused by equipment noise, slow environmental changes, etc., and avoid them interfering with lightning signal identification. On the other hand, the cutoff frequency must be lower than the signal change frequency of lightning disturbances to fully retain the high-frequency signal generated by sudden and strong interference from lightning strikes, preventing the loss of critical signals. Finally, by controlling the frequency of the high-pass filter, a clean high-frequency disturbance component is output, providing a reliable signal basis for the accurate identification and response to subsequent lightning strikes.

[0053] In one embodiment, such as Figure 5 As shown, obtaining the timestamp related to the occurrence of the lightning strike specifically includes: Step 1031: The transceiver at the first end detects the polarization disturbance caused by the lightning strike, generates a first trigger signal, and records the first time point.

[0054] Step 1031 is the initial triggering step for timestamp acquisition. The core of this step is to allow the device closest to the initial impact point of the lightning strike disturbance to capture the anomaly and leave a timestamp. The transceiver at the first end will monitor the polarization state of its received or transmitted signals in real time. When a lightning strike occurs, strong electromagnetic interference will instantly disrupt the polarization state of the optical path, causing high-frequency abrupt changes in signals such as phase shift (i.e., the high-frequency disturbance components mentioned above).

[0055] When the first transceiver detects a polarization disturbance that matches the characteristics of a lightning strike, it will immediately generate a first trigger signal to mark the first local discovery of the anomaly (which can be understood as an electronic marker signal used to trigger subsequent time recording actions). At the same time, it will accurately record the moment when the disturbance is detected and the trigger signal is generated, i.e., the first time point (for example, recorded as T1, accurate to the millisecond or microsecond level, to ensure that the time accuracy meets the needs of subsequent calculations).

[0056] Step 1032: After the transceiver at the second end detects the polarization disturbance, it generates a second trigger signal and transmits the second trigger signal to the transceiver at the first end. After the transceiver at the first end detects the second trigger signal, it records a second time point.

[0057] The second-end transceiver's detection and signal feedback provide a second critical time point for subsequent time calculations. Since the impact of lightning strikes on the communication link propagates along the link, the second-end transceiver will also detect polarization disturbances caused by the same lightning strike event. When the second-end transceiver identifies this disturbance as matching lightning strike characteristics, it generates a second trigger signal to mark the anomaly detected at the remote end. Unlike the first end, the second-end transceiver does not simply record the time locally; instead, it transmits the generated second trigger signal back to the first-end transceiver via the communication link. When the first-end transceiver successfully receives the second trigger signal from the second end, it immediately records the moment of reception, i.e., the second time point, denoted as T2, which must maintain the same time precision standard as T1.

[0058] Step 1033: Obtain the timestamp related to the occurrence of the lightning strike event based on the first time point corresponding to the first trigger signal and the second time point corresponding to the second trigger signal.

[0059] In this context, time point T1 represents the moment when the first end first detects the lightning strike disturbance, while time point T2 represents the moment when the first end receives the feedback signal from the second end. These two time points correspond to the two key nodes: the local initial detection and the arrival of feedback from the remote end. In practical applications, T1 and T2 will be calculated and processed according to specific requirements. Ultimately, by calculating based on these two time points, the timestamp directly related to the occurrence of the lightning strike event can be determined, providing a time basis for subsequent lightning strike location, analysis, or fault tracing.

[0060] In one embodiment, determining the location of the lightning strike based on the timestamp specifically includes: The time delay difference between the first trigger signal and the second trigger signal in the transceiver at the first end is obtained based on the first time point and the second time point; the location of the lightning strike event is obtained based on the time delay difference.

[0061] Specifically, obtaining the location of the lightning strike based on the time delay difference includes: subtracting the second time point from the first time point to obtain the time delay difference; calculating the distance a between the location of the lightning strike and the transceiver at the first end according to the formula a=L-(v×ΔT) / 2 to obtain the location of the lightning strike; where L is the total length of the optical fiber between the transceiver at the first end and the transceiver at the second end, v is the speed of light in the optical fiber, and ΔT is the time delay difference.

[0062] When a lightning strike occurs, the resulting polarization disturbance first affects the transceiver at the first end (corresponding to the first time point T1, i.e., the moment the first end generates the first trigger signal). Subsequently, this disturbance propagates along the optical fiber to the second end. Once the transceiver at the second end detects the disturbance, it generates a second trigger signal and transmits this signal back to the transceiver at the first end along the original link. The moment the transceiver at the first end receives the second trigger signal is the second time point T2. Therefore, the time delay difference ΔT = T2 - T1. It is worth noting that here it is assumed that the propagation speed of the second trigger signal in the optical fiber is the same as the propagation speed of the lightning disturbance, both approximately equal to the speed of light v in the optical fiber.

[0063] The location of the lightning strike is calculated using a formula based on the time delay difference ΔT. For example, Figure 6 As shown in the diagram, for example, at the lightning strike location, the lightning signal propagates a distance 'a' to the left (the transceiver at the first end), simultaneously generating a trigger signal (i.e., the first trigger signal); it propagates a distance 'b' to the right (the transceiver at the second end). Upon receiving the lightning signal, the receiving end also generates a trigger signal (i.e., the second trigger signal) and transmits it to the left. Therefore, the time delay difference ΔT between the two trigger signals on the left can be expressed by the following formula:

[0064] Where n is the refractive index of the optical fiber in the optical cable line, c is the speed of light in a vacuum, and a and b are the lengths of the optical fiber on either side of the lightning strike point, respectively. We can obtain:

[0065] Where v is the speed of light in the optical fiber, which may vary slightly due to differences in optical fiber material and refractive index. It needs to be calibrated according to the actual link parameters. In one embodiment, the propagation speed v = c / n, where n is the refractive index of the optical fiber and c is the speed of light in a vacuum.

[0066] Example 2: In Embodiment 1, a lightning strike detection method for an adaptive polarization controller was provided. In this embodiment, a lightning strike detection device for an adaptive polarization controller will be proposed. The lightning strike detection device for the adaptive polarization controller includes: a processor and a memory for storing processor-executable instructions; wherein, the processor is configured to execute the lightning strike detection method for the adaptive polarization controller described in Embodiment 1.

[0067] like Figure 7 As shown, the lightning strike detection device of the adaptive polarization controller includes a processor 21 and a memory 22, wherein the processor 21 and the memory 22 can be connected by a bus or other means.

[0068] Processor 21 can be a Central Processing Unit (CPU). Processor 21 can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips.

[0069] The memory 22, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the lightning strike detection method of the adaptive polarization controller in Embodiment 1 of the present invention. The processor executes various functional applications and training processes by running the non-transitory software programs, instructions, and modules stored in the memory.

[0070] The memory 22 may include a program storage area and a training storage area. The program storage area may store the operating system and applications required for at least one function; the training storage area may store training data created by the processor. Furthermore, the memory may include high-speed random access memory and non-transitory memory, such as at least one disk storage device, flash memory, or other non-transitory solid-state storage device. In some embodiments, the memory 22 may optionally include memory remotely located relative to the processor, which can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof. The one or more modules stored in the memory 22, when executed by the processor 21, perform functions such as... Figure 1The lightning strike detection method for the adaptive polarization controller in Embodiment 1 is shown. For specific details of the above-described lightning strike detection method for the adaptive polarization controller, please refer to the relevant documentation. Figure 1 , Figure 2 and Figure 3 The relevant descriptions and effects in the embodiments shown are for reference only and will not be repeated here. This embodiment also provides a computer storage medium storing a computer program that can be executed by a processor to complete the lightning strike detection method of the adaptive polarization controller described in Embodiment 1.

[0071] The computer storage medium stores computer-executable instructions, which can execute the lightning strike detection method of the adaptive polarization controller in any of the above method embodiments. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium may also include combinations of the above types of memory.

[0072] The specific steps of the lightning strike detection method of the adaptive polarization controller are described in Example 1, and will not be repeated in this example.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A lightning strike detection method based on an adaptive polarization controller, wherein transceivers are respectively installed at both ends of an optical cable line, and an adaptive polarization controller is integrated into the optical cable line, characterized in that, The method includes: The polarization state of the input optical signal is compensated in real time by the adaptive polarization controller, and the phase shift change signal of each phase shifter in the adaptive polarization controller is monitored in real time. The phase shift change signal is subjected to high-pass filtering to obtain high-frequency disturbance components. When the high-frequency disturbance components exceed a preset threshold, it is determined that a lightning strike event has occurred. Obtain the timestamp associated with the lightning strike, and determine the location of the lightning strike based on the timestamp.

2. The lightning strike detection method based on an adaptive polarization controller according to claim 1, characterized in that, The real-time compensation of the polarization state of the input optical signal through the adaptive polarization controller specifically includes: Obtain the optical power at the feedback port of the adaptive polarization controller; The control signal for adjusting the phase modulation amount of the phase shifter in the adaptive polarization controller is obtained based on the optical power of the feedback port. The control signal is applied to the phase shifter to change the phase modulation amount of the phase shifter; By changing the phase modulation amount of the phase shifter to minimize the optical power at the feedback port of the adaptive polarization controller, real-time compensation of the polarization state of the input optical signal can be achieved.

3. The lightning strike detection method based on an adaptive polarization controller according to claim 1, characterized in that, The acquisition of the timestamp related to the occurrence of the lightning strike specifically includes: The transceiver at the first end detects the polarization disturbance caused by the lightning strike, generates the first trigger signal, and records the first time point; After the transceiver at the second end detects the polarization disturbance, it generates a second trigger signal and transmits the second trigger signal to the transceiver at the first end. After the transceiver at the first end detects the second trigger signal, it records a second time point. The timestamps related to the occurrence of the lightning strike are obtained based on the first time point corresponding to the first trigger signal and the second time point corresponding to the second trigger signal.

4. The lightning strike detection method based on an adaptive polarization controller according to claim 3, characterized in that, The step of determining the location of the lightning strike based on the timestamp specifically includes: The time delay difference between the first trigger signal and the second trigger signal in the transceiver at the first end is obtained based on the first time point and the second time point; the location of the lightning strike event is obtained based on the time delay difference.

5. The lightning strike detection method based on an adaptive polarization controller according to claim 4, characterized in that, The step of determining the location of the lightning strike based on the time delay difference specifically includes: The time delay difference is obtained by subtracting the second time point from the first time point; The distance 'a' between the location of the lightning strike and the transceiver at the first end is calculated using the formula a=L-(v×ΔT) / 2 to obtain the location of the lightning strike. Where L is the total length of the optical fiber between the transceiver at the first end and the transceiver at the second end, v is the speed of light in the optical fiber, and ΔT is the time delay difference.

6. The lightning strike detection method based on an adaptive polarization controller according to claim 1, characterized in that, The step of performing high-pass filtering on the phase shift change signal to obtain high-frequency disturbance components specifically includes: The phase shift change signal is input to a high-pass filter to extract the high-frequency disturbance component in the phase shift change signal; The cutoff frequency of the high-pass filter is set to be higher than the signal change frequency when the adaptive polarization controller compensates for normal polarization disturbances, and lower than the signal change frequency corresponding to polarization disturbances caused by lightning strikes.

7. The lightning strike detection method based on an adaptive polarization controller according to claim 6, characterized in that, The cutoff frequency of the high-pass filter is set to above 100kHz.

8. The lightning strike detection method based on an adaptive polarization controller according to claim 6, characterized in that, When the adaptive polarization controller includes a first phase shifter and a second phase shifter, the transfer matrix of the adaptive polarization controller is: ； in, The complex amplitude of the optical field at the master port of the adaptive polarization controller. The complex amplitude of the optical field at the feedback port of the adaptive polarization controller. The horizontal polarization component of the input optical signal. The vertical polarization component of the input optical signal. This is the phase modulation amount of the first phase shifter. This is the phase modulation amount of the second phase shifter.

9. A lightning strike detection device with an adaptive polarization controller, characterized in that, The lightning strike detection device of the adaptive polarization controller includes: a processor and a memory for storing processor-executable instructions; The processor is configured to execute the lightning strike detection method of the adaptive polarization controller according to any one of claims 1-8.

10. A non-volatile computer storage medium, characterized in that, The computer storage medium stores computer-executable instructions, which are executed by one or more processors to perform the lightning strike detection method of the adaptive polarization controller according to any one of claims 1-8.

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