A power transmission line multi-parameter sensing method and system

Abstract

The present disclosure belongs to the technical field of power transmission line state monitoring, and provides a power transmission line multi-parameter sensing method and system, comprising the following steps: acquiring a first carrier and a second carrier; performing energy extraction on the acquired first carrier to obtain a third carrier containing a sensing signal; extracting a back-to-back frequency shift signal of the acquired second carrier, and sensing a first parameter of the power transmission line based on the back-to-back frequency shift signal; sensing a second parameter of the power transmission line based on a modulation signal of the obtained third carrier; and combining the first parameter and the second parameter to obtain operation information of the power transmission line. The present disclosure supplies power to a remote power tower through the first carrier, measures the stress at each position of the power transmission line through the second carrier, and acquires feedback of environmental information on the power tower through the third carrier, so as to jointly acquire the operation safety information of the power transmission line by combining the first and second parameters carried on the second and third carriers.

Description

TECHNICAL FIELD

[0001] The present disclosure belongs to the technical field of power transmission line state monitoring, and particularly relates to a power transmission line multi-parameter sensing method and system. BACKGROUND

[0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.

[0003] The power pipeline is long in distance, large in span, and complex in environment, and is easily affected by weather phenomena such as wind, rain, ice, and various natural factors such as temperature and humidity changes. The operation and maintenance personnel found that local micro-meteorological factors, such as icing, can cause serious damage to overhead power transmission lines, and some phenomena can even cause the collapse of power transmission towers, which seriously affects the safe and stable operation of the power transmission line. Therefore, accurate collection and analysis of small-range meteorological information around the overhead power transmission line can monitor and warn the power transmission line. For example, by monitoring the local environmental factors of the power transmission line, the local stress of the power transmission line can be effectively predicted, so as to prevent the problem of the line being pulled apart due to exceeding the rated breaking force of the line.

[0004] In the prior art, environmental collection sensors are usually arranged on the towers of the power transmission line, and power supply is realized through solar panels, and data transmission is realized through wireless data transmission. However, the effect of this power supply and data transmission method is not good, and it is easily affected by extreme harsh environments. For example, in areas with long-term hazy weather conditions, shady canyons, and poor communication underground pipelines, solar panels cannot achieve stable and effective power supply, and wireless data transmission may be blocked.

[0005] On the other hand, the prior art also uses optical fiber energy and signal co-transmission to realize power supply and signal transmission for the environmental collection sensors on the towers. For example, patent document CN111404273A discloses an overhead line remote sensing monitoring system, in which the sensing monitoring device located on one side of the remote overhead line can receive continuous laser through power optical cable and convert the continuous laser into electrical energy through a photoelectric conversion unit to realize power supply, and at the same time, the monitoring data is transmitted back to the monitoring center through the power optical cable. This scheme can realize the simultaneous transmission of energy and information, thereby realizing real-time sensing monitoring of the overhead line. However, in the above scheme, the sensor can only collect related environmental data on the power tower, and cannot effectively monitor the entire area of the transmission line between the towers or between the towers and the substation. When the local environment of the transmission line away from the tower changes abnormally, it is difficult to effectively predict the risk factors. Secondly, due to the long distance and multiple nodes of the power transmission line, the power supply by the continuous laser method consumes a lot of energy in the transmission process, and the effect of energy and signal co-transmission is not good.

[0006] In addition, a global intelligent monitoring method is mentioned in the prior art. For example, patent document CN113607449A discloses a bridge cluster structure global intelligent monitoring and safety warning system for obtaining distributed strain monitoring data and temperature field data of the bridge structure. The distributed sensing subsystem includes a multi-loop distributed strain sensing optical fiber and various environmental sensors. In addition, the distributed Brillouin optical fiber sensing technology uses a common single-mode optical fiber used in optical fiber communication as a sensing medium. Since the optical fiber itself is a sensor, it can achieve continuous monitoring of multiple measurement points in space. However, although this document provides an inspiration for global intelligent monitoring, there is still no global intelligent monitoring used in the global detection of long-distance, large-scale, and relatively large environmental factor difference power transmission lines in the prior art. Secondly, due to the long transmission distance of the power transmission line, the large amount of data to be transmitted, the multiple data types, and the complex types and quantities of devices, and the limited optical fiber resources in the power transmission line, it also increases the difficulty of joint collection of various environmental data. SUMMARY

[0007] To solve the above problems, the present disclosure provides a power transmission line multi-parameter sensing method and system. The first carrier is used to power the remote power tower, the second carrier is used to measure the stress at each position of the power transmission line, and the third carrier is used to obtain the feedback of the environmental information on the power tower. Thus, the first and second parameters carried on the second and third carriers are jointly obtained to obtain the operation safety information of the power transmission line.

[0008] According to some embodiments, the first aspect of the present disclosure provides a power transmission line multi-parameter sensing method, which adopts the following technical solution:

[0009] A power transmission line multi-parameter sensing method, comprising the following steps:

[0010] Obtaining a first carrier and a second carrier of a substation node;

[0011] Extracting the energy of the obtained first carrier to obtain a third carrier containing a sensing signal;

[0012] Extracting the back-to-back frequency shift signal of the obtained second carrier, and sensing the first parameter of the power transmission line based on the back-to-back frequency shift signal;

[0013] Sensing the second parameter of the power transmission line based on the modulation signal of the obtained third carrier;

[0014] Combining the first parameter and the second parameter to obtain the operation information of the power transmission line;

[0015] The first carrier, the second carrier and the third carrier are transmitted through a single-mode optical fiber; the transmission directions of the first carrier and the second carrier are consistent, and the transmission directions of the first carrier and the second carrier are opposite to the transmission direction of the third carrier.

[0016] As a further technical limitation, in the process of acquiring the first carrier and the second carrier of the substation node, the first carrier and the second carrier are collected based on the substation node, and the first carrier and the second carrier obtained in the substation node are transmitted to the tower of the transmission line through the single-mode optical fiber, that is, the acquisition of the first carrier and the second carrier of the substation node is realized.

[0017] As a further technical limitation, the pulse time-of-flight method is used to calculate the backscattering frequency shift signal of the second carrier, and the correlation between the intensity of the Brillouin scattering spectrum in the backscattering frequency shift signal and the transmission distance in the single-mode optical fiber is obtained; based on the correlation and the ambient temperature, the optical fiber strain data at a certain transmission distance in the single-mode optical fiber is obtained.

[0018] Further, the first parameter at least includes environmental data, and the environmental data includes environmental wind speed, environmental wind direction, environmental air pressure, environmental temperature and environmental humidity; the second parameter is the optical fiber strain data, and the optical fiber strain data depends on the size of the optical fiber strain and the optical fiber strain position corresponding to the size of the optical fiber strain.

[0019] According to some embodiments, the second scheme of the present disclosure provides a power transmission line multi-parameter sensing system for realizing the power transmission line multi-parameter sensing method provided in the first scheme, and adopts the following technical scheme:

[0020] A power transmission line multi-parameter sensing system, one substation node, one or more power transmission line tower nodes, and a power transmission line between the nodes; wherein the one substation node and the one or more power transmission line tower nodes are connected in sequence, and the power transmission line is divided into multiple sections by the multiple power transmission line tower nodes; a first carrier, a second carrier and a third carrier are transmitted in the single-mode optical fiber in each section of the multiple sections of the power transmission line.

[0021] As a further technical limitation, the substation node includes a host, a first carrier laser, a second carrier demodulator, an optical fiber strain monitoring unit and a second wavelength division multiplexer; the first carrier laser, the second carrier demodulator and the optical fiber strain monitoring unit are connected to the single-mode optical fiber through the multiplexing ports of the second wavelength division multiplexer, respectively; and the host is connected to the output ports of the second carrier demodulator and the optical fiber strain monitoring unit, respectively.

[0022] As a further technical limitation, the power transmission line tower node comprises a first wavelength division multiplexer, a second wavelength division multiplexer, an optical splitter, a coupler and a sensing monitoring device; wherein the first wavelength division multiplexer receives the input of the single-mode optical fiber of the previous node, inputs the first carrier to the optical splitter, and inputs the second carrier to the second wavelength division multiplexer; the output end of the optical splitter is connected to the input end of the sensing monitoring device and the second wavelength division multiplexer, respectively; the second wavelength division multiplexer multiplexes and outputs the second carrier and the split first carrier to the next node, simultaneously receives the input of the single-mode optical fiber of the next node, and inputs the third carrier and the second carrier back-to-back frequency shift signal to the coupler; the input end of the coupler is connected to the output end of the sensing monitoring device and the second wavelength division multiplexer, respectively.

[0023] According to some embodiments, the third aspect of the present disclosure provides a power transmission line multi-parameter sensing system, which adopts the following technical solution:

[0024] A power transmission line multi-parameter sensing system comprises:

[0025] An acquisition module is configured to acquire a first carrier and a second carrier of a substation node.

[0026] An extraction module is configured to extract the energy of the acquired first carrier to obtain a third carrier containing a sensing signal.

[0027] A sensing module is configured to extract a back-to-back frequency shift signal of the acquired second carrier, sense a first parameter of the power transmission line based on the back-to-back frequency shift signal, and sense a second parameter of the power transmission line based on a modulation signal of the obtained third carrier.

[0028] A joint module is configured to jointly obtain the first parameter and the second parameter to obtain operation information of the power transmission line.

[0029] The first carrier, the second carrier and the third carrier are transmitted through a single-mode optical fiber; the transmission directions of the first carrier and the second carrier are consistent, and the transmission directions of the first carrier and the second carrier are opposite to the transmission direction of the third carrier.

[0030] According to some embodiments, the fourth aspect of the present disclosure provides a computer readable storage medium, which adopts the following technical solution:

[0031] A computer readable storage medium has a program stored thereon, and the program is executed by a processor to implement the steps of the power transmission line multi-parameter sensing method according to the first aspect of the present disclosure.

[0032] According to some embodiments, the fifth aspect of the present disclosure provides an electronic device, which adopts the following technical solution:

[0033] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor, and the processor implements the steps in the power transmission line multi-parameter sensing method according to the first aspect of the present disclosure when executing the program.

[0034] Compared with the prior art, the present disclosure has the following beneficial effects:

[0035] 1. The present disclosure reasonably allocates the optical signal energy on each section of the entire power transmission line, so that the transmitting end of the first carrier can supply power to all related devices on the entire line with minimum power, saving energy while ensuring the reliability of data acquisition.

[0036] 2. The present disclosure integrates multiple signals in the same single-mode optical fiber for transmission by wavelength division multiplexing, fully saving optical fiber resources and providing sufficient redundancy for subsequent upgrading and expansion of the power system.

[0037] 3. The present disclosure collects environmental data and strain data comprehensively, so that the method can obtain more and more accurate data along the power transmission line, providing sufficient data sources for the analysis process of the operation risk of the power transmission line, and providing reliable guarantee for the diversity and accuracy of the analysis algorithm. BRIEF DESCRIPTION OF DRAWINGS

[0038] The accompanying drawings, which form a part of the present disclosure, are intended to provide further understanding of the present disclosure, and the schematic embodiments of the present disclosure and their descriptions are used to explain the present disclosure, and do not constitute improper limitations on the present disclosure.

[0039] Figure 1 is a flowchart of the power transmission line multi-parameter sensing method in the first embodiment of the present disclosure;

[0040] Figure 2 is a schematic diagram of the erection of the power transmission line multi-parameter sensing system in the second embodiment of the present disclosure in the power transmission line;

[0041] Figure 3 is a network architecture schematic diagram of the power transmission line multi-parameter sensing system in the second embodiment of the present disclosure;

[0042] Figure 4 is a network architecture schematic diagram of the transformer substation node in the power transmission line multi-parameter sensing system in the second embodiment of the present disclosure;

[0043] Figure 5 is a schematic diagram of the optical fiber strain monitoring unit in the power transmission line multi-parameter sensing system in the second embodiment of the present disclosure;

[0044] Figure 6 is a network architecture schematic diagram of the power transmission line tower node in the power transmission line multi-parameter sensing system in the second embodiment of the present disclosure;

[0045] Figure 7 This is a structural block diagram of the multi-parameter sensing system for power transmission lines in Embodiment 3 of this disclosure. Detailed Implementation

[0046] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0047] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0048] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0049] Where there is no conflict, the embodiments and features described herein can be combined with each other.

[0050] Example 1

[0051] Embodiment 1 of this disclosure introduces a multi-parameter sensing method for power transmission lines.

[0052] like Figure 1 The multi-parameter sensing method for transmission lines shown includes the following steps:

[0053] Step S01: Generate the first carrier and the second carrier, and transmit the first carrier and the second carrier from the substation node to the transmission line tower;

[0054] Step S02: After receiving the first carrier wave, the sensing and monitoring device on the transmission line tower acquires energy to generate a third carrier wave modulated with a sensing signal, and transmits the third carrier wave from the transmission line tower back to the substation node;

[0055] Step S03: After receiving the back-frequency shift signal of the second carrier and the third carrier respectively, the first parameter of the transmission line is sensed based on the back-frequency shift signal, and the second parameter of the transmission line is sensed based on the demodulation of the third carrier.

[0056] In step S01, the method in this embodiment can be used to sense relevant parameters on a transmission line within a certain area of ​​a power system.

[0057] Specifically, in this embodiment, a region can be all the areas covered by a substation. The substation supplies power to all load users within its jurisdiction through power transmission equipment. To achieve this power supply, multiple transmission lines are required. Within each transmission line, a variable number of power poles can be installed depending on the distance, thus achieving an overhead transmission line. Generally, the distance between two poles on a high-voltage transmission line is between 40 and 70 meters. Additionally, a high-voltage power pole is usually installed near each type of substation.

[0058] As one or more implementation methods, the substation node is directly or indirectly connected to one or more transmission line towers via single-mode optical fiber; wherein, the distance of the transmission line is the sum of the distance of the transmission line between the substation equipment room and the transmission line tower and the distance of the transmission line between the transmission line towers.

[0059] like Figure 2 The multi-parameter sensing system for transmission lines shown is installed on the transmission lines. In this embodiment, a transmission line can be a line starting from a substation node and reaching the end of the load user, or it can be a line between two substation nodes. In this embodiment, the definition of a transmission line is simply to ensure that multiple linear towers are sequentially connected in the current transmission line.

[0060] In existing technologies, communication equipment in substation equipment rooms and communication equipment on various transmission line towers typically uses optical power cables (OPGW, Optical Fiber Composite Overhead Ground Wire) for wired data transmission. The substation sends command data to the transmission line towers, and the relevant equipment on the towers collects the corresponding data and feeds it back to the substation. The substation uses a large-scale equipment room to aggregate and process the data. The method in this embodiment can rely on existing OPGW optical power cables pre-laid between the substation equipment room and the transmission line towers.

[0061] In this embodiment, to maximize the utilization efficiency of existing power optical cable resources, the method in this embodiment can be implemented using only one single-mode optical fiber in the power optical cable.

[0062] As one or more implementations, the sensing monitoring device, the optical splitter, the coupler, the first wavelength division multiplexer, and the second wavelength division multiplexer are located on a power transmission line tower, and the sensing monitoring device comprises an energy storage unit and a sensing unit; wherein the optical signal of the uplink power transmission line tower in the single-mode optical fiber is demultiplexed by the first wavelength division multiplexer to realize first carrier output and second carrier output, the first carrier output is sent to the receiving end of the energy storage unit of the sensing monitoring device on the downlink power transmission line tower after passing through the optical splitter, and the second carrier is multiplexed by the second wavelength division multiplexer and output to the downlink power transmission line tower; the energy storage unit performs photoelectric conversion on the first carrier and realizes power supply to the sensing unit of the sensing monitoring device; the sensing unit sends the third carrier modulated with the sensing signal to the coupler to realize the combination of the third carrier output and the backscattering frequency shift signal of the second carrier from the downlink power transmission line tower, and the combination is output to the uplink power transmission line tower through the first wavelength division multiplexer.

[0063] The sensing monitoring device in the embodiment can adopt a sensing monitoring device with photoelectric conversion function and photovoltaic power supply function commonly used in the prior art. Generally, such a sensing monitoring device can include a photovoltaic cell, a super capacitor, a voltage converter, various sensors, and an optical communication unit. The energy storage unit shown in the foregoing mainly includes a photovoltaic cell, a super capacitor, and a voltage converter, and the sensing unit can include various sensors and an optical communication unit. The photovoltaic cell can be formed of indium gallium arsenide (InGaAs) material, which can split electrons and holes in a semiconductor PN junction through photovoltaic effect and make the electrons move directionally to generate a potential difference. When a super capacitor is connected in parallel across the photovoltaic cell, the electrical energy generated by the photovoltaic cell can be stored. In the embodiment, the super capacitor can be a double-layer capacitor, which has the characteristics of instantaneous high power and high power density.

[0064] The output end of the photovoltaic cell and the super capacitor connected in parallel can also be connected to multiple voltage converters. Some of the voltage converters can be voltage drop converters, and the rest can be voltage boost converters.

[0065] In the embodiment, a DC-DC converter commonly used in the prior art is adopted; in other embodiments, other types of converters can also be adopted. The DC-DC converter in the embodiment modulates the output voltage to a stable voltage, such as 3.3V or 5V, etc. These stable voltages can be adapted to various sensors used in the sensing monitoring device. In addition, in order to make the output voltage more stable, a low-dropout linear voltage regulator can also be added to the corresponding circuit part in the embodiment.

[0066] As one or more implementations, the sensing unit collects environmental data on the tower of the power transmission line based on the power supply of the energy storage unit; the sensing unit comprises one or more weather sensors.

[0067] The plurality of sensors used in the embodiment can be temperature and humidity sensors, air pressure sensors, wind speed and direction sensors, etc. The voltage required by the sensors in the embodiment is the stable voltage output by the voltage converter or voltage stabilizer. In the embodiment, the temperature and humidity sensor uses an SHTC3 chip, and the air pressure sensor uses an MS5611-01BA03-50 chip; in other embodiments, other types can also be used.

[0068] The data collected by the plurality of sensors can be read and preliminarily sorted by a single-chip microcomputer in the sensing and monitoring device. In the embodiment, the MSP430G2553 single-chip microcomputer with analog / digital signal conversion function is used to collect environmental data such as wind speed, wind direction, temperature, humidity, air pressure, etc.; in other embodiments, other types can also be used. It should be noted that the single-chip microcomputer in the embodiment is also powered by the energy collected by the photocell after voltage conversion.

[0069] In addition, the sensing and monitoring device in the embodiment also comprises an optical communication unit. The unit uses RS232 or RS485 protocol to realize optical-electric conversion of signals. In other words, the optical communication unit in the embodiment is similar to the optical communication unit in the prior art, which has an interface chip conforming to RS232 or RS485 on the structure, so as to receive the environmental data output by the single-chip microcomputer and modulate it into optical signals and send it to the single-mode optical fiber; in other embodiments, other types can also be used.

[0070] In the embodiment, a sensing and monitoring device can be included on each tower where the power transmission line is located, in other words, the towers and the sensing and monitoring devices are one-to-one corresponding. In addition, each tower has a splitter, a coupler and two wavelength division multiplexers in addition to the sensing and monitoring device. After passing through the wavelength division multiplexers, the splitter only splits the first carrier. In the embodiment, the splitter can split the first carrier in the 1310nm waveband; in other embodiments, other types can also be used. It is easy to understand that the entire power transmission line starting from the transformer substation room should have a splitter on each tower it passes through, of course, if it is located at the end of the entire power transmission line, the splitter actually does not play any role.

[0071] As one or more implementations, the splitter is set corresponding to the sensing and monitoring device and is located on each other power transmission line tower except the one farthest from the transformer substation room network distance, and is numbered in order according to the network distance from the transformer substation room.

[0072] In the embodiment, each optical splitter on the tower can be configured as a 1:2 structure, or it can be considered that the method in the embodiment can be implemented by using only the 1:2 channel of the optical splitter. The optical splitter can not be a special element added in the embodiment. In the embodiment, after the optical signal on the previous tower is transmitted to the current tower through the single-mode optical fiber, the first carrier is extracted through the first wavelength division multiplexer, and then the optical signal is split through the optical splitter.

[0073] After the optical splitter is split by the 1:2 structure, the first output light and the second output light are obtained from the first carrier according to the preset splitting ratio. The first output light is connected to the sensing and monitoring device on the same tower through the first output end of the optical splitter, and the second output light is connected to the single-mode optical fiber through the second output end of the optical splitter and the second wavelength division multiplexer, and is transmitted to the next tower.

[0074] Similarly, if the sensing and monitoring device on a certain tower generates a third carrier optical signal, the third carrier optical signal is transmitted to the previous tower through the coupler and the first wavelength division multiplexer.

[0075] Regarding the preset splitting ratio, different numbered optical splitters are different. Specifically, the calculation method can be obtained from the following formula. If there are N optical splitters in total, the splitting ratio of the nth optical splitter is at least

[0076]

[0077] where ω n is the required power of the nth sensing and monitoring device, a n is the nth power of the attenuation coefficient a of the first carrier in the single-mode optical fiber, x i is the transmission distance between the tower of the ith optical splitter and the tower of the transmission line above it, and T is the first carrier transmission power of the substation.

[0078] In the embodiment, if there are N optical splitters in total, it can be considered that the entire transmission line includes N+1 towers. The splitting ratio of the nth optical splitter should be obtained by taking the power of all optical signals transmitted to the nth tower as the denominator and taking the required working power of the sensing and monitoring device on the current tower as the numerator.

[0079] Specifically, this ratio multiplied by the total power transmitted from the previous tower can achieve the power supply for the sensor monitoring device, so that the sensing and monitoring device can have sufficient energy supply, and the remaining energy is transmitted to the next tower.

[0080] Therefore, the light signal intensity at the input end of the splitter on the nth tower is affected by the splitting of the previous splitter, and is determined by the natural attenuation of the light signal during fiber transmission and the transmission intensity of the light signal in the substation. For the first splitter, the received attenuation is a multiple of the original light power intensity T, and the multiple is the product of x1 and the attenuation coefficient a. After the splitter divides ω1 power to the sensing and monitoring device on the first tower, the remaining a x1 T- ω1 is transmitted to the next tower. Therefore, the light intensity received by the next tower is a x2(a x1 T- ω1), and the required power of the next tower is ω2. Similarly, it can be obtained that when the light power transmitted to the nth tower is T, the power is attenuated and split to According to the required power of the sensing and monitoring device at this time, the minimum splitting ratio of the splitter can be obtained. Of course, in the prior art, in order to fully ensure that the sensing and monitoring device can obtain sufficient electrical energy, the value of the minimum splitting ratio can be increased within a certain range, but this requires an increase in the carrier transmission power of the substation.

[0081] It should be noted that in order to enable the sensing and monitoring devices on all towers on the transmission line to receive sufficient energy for effective operation, the total power of the light signal received by the Nth splitter can be greater than or equal to the required power of the last sensing and monitoring device, that is, According to the formula, the minimum value of T can also be solved, thereby limiting the transmission power of the light signal to the minimum and saving energy. Generally, since the power of the second carrier is relatively certain, the power of the first carrier can be adjusted to adjust T.

[0082] As one or more embodiments, the required power of the nth sensing and monitoring device is at least

[0083]

[0084] wherein S l is the operating power of the lth sensor in the sensing and monitoring device, L is the number of sensors in the sensing and monitoring device, b is the operating power of the optical communication module and the single-chip microcomputer module in the sensing unit of the sensing and monitoring device, and k is the photoelectric conversion efficiency of the energy storage unit in the sensing and monitoring device.

[0085] In the present embodiment, the sum of the operating power of the plurality of sensors, the power of the optical communication module, the power of the single-chip microcomputer, and the power of the energy storage unit is the required power of the sensing and monitoring device. If the sensing and monitoring devices on the plurality of towers are set to the same signal, the value of the required power can be the same or similar.

[0086] Since the energy storage unit basically does not consume power, but stores light energy through a certain power conversion efficiency, in the embodiment, the power consumption of the energy storage unit is not specifically calculated. For the sensing unit, the power consumption can be obtained by summing the power of the sensor and the power of other modules, that is, Therefore, according to the photoelectric conversion efficiency, the power required by the sensing monitoring device can be known.

[0087] It should be noted that in the embodiment, in order to simultaneously realize power supply to the sensing monitoring device on the tower and collection of frequency shifts at each position of the optical fiber, two different wavelength carriers, i.e., a first carrier and a second carrier, can be generated at the same time. In the embodiment, the wavelength of the first carrier is set to 1310 nm, and the wavelength of the second carrier is set to 1550 nm. The attenuation coefficients of the two in a single-mode optical fiber are 0.35 dB / m and 0.2 dB / m, respectively. Since the attenuation of the optical signal in the 1550 nm or 1450 nm band is lower, in order to realize the minimum transmission attenuation of the first carrier optical signal, the first carrier can also be set to other wavelengths. The first carrier and the second carrier can be transmitted from the transformer substation to the tower through a single-mode optical fiber through a wavelength division multiplexing device at the same time.

[0088] In step S02, the sensing monitoring device in the embodiment can receive the first carrier split by the optical splitter, and realize the photoelectric conversion function based on the optical power of the carrier, to realize the related functions of the sensing monitoring device.

[0089] In the embodiment, the functions of the sensing monitoring device are as described above. The signal collection of the sensor can be realized through the power supply of the photovoltaic cell, the super capacitor, and the voltage converter. The signals collected by the plurality of sensors are sent to the optical communication module after simple data processing by the single-chip microcomputer. The optical communication module converts the electrical signal sent by the single-chip microcomputer into an optical signal of the third carrier. The optical communication module and the single-chip microcomputer need to be powered by the photovoltaic cell.

[0090] The sensing monitoring device in the embodiment can collect a plurality of environmental data through a plurality of sensors, and simultaneously perform photoelectric conversion on the data through the optical communication module to realize signal modulation on the third carrier, and feed back the third carrier to the transformer substation. In the embodiment, the wavelength of the third carrier is 1450 nm, which can fully realize the signal differentiation between 1310 nm and 1550 nm, and the differentiation from the 1550 nm frequency shift signal. In other embodiments, the importance of signals in a plurality of different wavelength bands, and the transmission and attenuation characteristics of light in different wavelength bands can be considered to realize different wavelength allocation modes of the first carrier, the second carrier, and the third carrier.

[0091] Through the two-in-one function of the coupler on each tower, the embodiment realizes the output of the data on the current tower at 1450 nm, the merging of the 1450 nm optical signal returned from the next tower, and the entering of the single-mode optical fiber after the wavelength division multiplexer, and the transmission feedback to the previous tower.

[0092] In step S03, after the sensing monitoring device returns the data, the wavelength division demultiplexing device arranged at the end of the transformer substation can receive the second carrier and its frequency shift and the third carrier signal respectively.

[0093] As one or more implementation manners, the back frequency shift signal of the second carrier is collected based on a coherent light demodulation manner; in the coherent light demodulation manner, the intensity of the reference light signal is a preset multiple of the intensity of the third carrier.

[0094] In the embodiment, the back frequency shift signal of the second carrier can be collected based on the commonly used coherent light demodulation manner in the prior art. This part will be specifically described in Embodiment 2. It should be noted that the embodiment also specifies the multiple relationship between the reference light and the emitted light in the coherent light demodulation process.

[0095] As one or more implementation manners, the preset multiple is set based on the distance of the power transmission line, the optical fiber stress, and the environmental temperature. If the power transmission line is long, or the optical fiber attenuation coefficient caused by the stress and the temperature is large, the preset multiple can be set to be small, that is, the proportion of the reference light is small. In the embodiment, the reference light accounts for 10% of the light emitted by the laser.

[0096] As one or more implementation manners, step S03 further includes: using a pulse time-of-flight method to calculate the back frequency shift signal of the second carrier to obtain the correlation between the intensity of the Brillouin scattering spectrum in the back frequency shift signal and the transmission distance in the single-mode optical fiber; and based on the correlation and the current environmental temperature, obtaining the optical fiber strain at a certain transmission distance in the single-mode optical fiber.

[0097] According to the definition of the optical fiber strain in the prior art, the intensity of the Brillouin frequency shift signal and the optical fiber strain are linearly related, so the estimated value of the optical fiber strain can be obtained according to this relationship. It should be noted that in order to collect the Brillouin frequency shift signal at different optical fiber distances, the pulse time-of-flight method can be used to obtain the correlation between the optical fiber distance and the scattering spectrum intensity.

[0098] As one or more implementations, the first parameter is environmental data, and the data format is a vector D1=[α,β,γ,δ,∈], wherein α is an environmental wind speed, β is an environmental wind direction, γ is an environmental air pressure, δ is an environmental temperature, and ∈ is an environmental humidity; the second parameter is fiber strain data D2=[λ,μ], wherein λ is a fiber strain size, and μ is a fiber strain position corresponding to the fiber strain size.

[0099] The related parameters obtained by the technical solution described above through steps such as demultiplexing, demodulation, and decoding in the embodiment include two types of environmental data and fiber strain data. The two different parameters are represented in a vector manner. Meanwhile, some intelligent algorithms commonly used in the prior art can be used to achieve sufficient operation based on the above parameters collected at different time points, and the optimal power transmission line operation and maintenance scheme is solved.

[0100] Embodiment Two

[0101] Embodiment Two of the present disclosure introduces a power transmission line multi-parameter sensing system for implementing the power transmission line multi-parameter sensing method introduced in Embodiment One.

[0102] As shown in Figure 3 a power transmission line multi-parameter sensing system, comprising a substation node, one or more power transmission line tower nodes, and a power transmission line between the nodes; wherein the substation node and the one or more power transmission line tower nodes are sequentially connected, the power transmission line is divided into multiple sections by the multiple power transmission line tower nodes, and the first carrier wave, the second carrier wave, and the third carrier wave are transmitted in the corresponding single-mode optical fiber of each section of the multiple power transmission line sections.

[0103] As shown in Figure 4 the network architecture of the substation node in the power transmission line multi-parameter sensing system, the substation node comprises a host, a first carrier wave laser, a second carrier wave demodulator, a fiber strain monitoring unit, and a second wavelength division multiplexer; wherein the first carrier wave laser, the second carrier wave demodulator, and the fiber strain monitoring unit are connected to the single-mode optical fiber through the multiplexing ports of the second wavelength division multiplexer; the host is connected to the output ports of the second carrier wave demodulator and the fiber strain monitoring unit; wherein the first carrier wave laser can emit a 1310nm carrier wave and transmit it to the single-mode optical fiber through one port of the second wavelength division multiplexer, and the fiber strain monitoring unit can also emit a 1550nm carrier wave. The second carrier wave demodulator receives the third carrier wave signal from the sensing and monitoring device of the tower, and the fiber strain monitoring unit can also collect the frequency-shifted second carrier wave in the backward direction.

[0104] It should be noted that, since Embodiment 1 describes the first and second wavelength division multiplexers on each tower, the first wavelength division multiplexer's function is to demultiplex uplink data and multiplex downlink data. The second wavelength division multiplexer, however, multiplexes uplink data and demultiplexes downlink data. Therefore, based on the actual function of the wavelength division multiplexer, this embodiment also refers to the wavelength division multiplexer located in the substation or on the tower where the substation is located as the second wavelength division multiplexer. The first wavelength division multiplexer is not present in the substation's local equipment room or on the substation's local tower. Similarly, the second wavelength division multiplexer is not present on the tower at the very end of the transmission line, or such a multiplexer has no practical application significance in this embodiment.

[0105] like Figure 5 The fiber optic strain monitoring unit in the multi-parameter sensing system of the transmission line shown includes a narrow-linewidth laser, a first coupler, a second coupler, a pulse modulation unit, a scrambler, a first erbium-doped fiber amplifier, a second erbium-doped fiber amplifier, an optical circulator, a photodetector, and a microwave sweeper. The narrow-linewidth laser generates laser light, which is input to the pulse modulation unit and the scrambler via the first coupler. The pulse modulation unit amplifies the laser light and inputs it into a single-mode fiber via the first erbium-doped fiber amplifier and the optical circulator. The back-shift signal from the single-mode fiber received by the optical circulator passes through the second erbium-doped fiber amplifier and, together with the output laser light from the scrambler, passes through the second coupler and is received by the photodetector, then forwarded to the microwave sweeper. The microwave sweeper is connected to the main unit in the substation node.

[0106] Understandably, in the fiber optic strain monitoring unit, the optical circulator enables the device to emit amplified 1550nm laser light and receive the returned scattered spectrum. The first coupler and scrambler generate correlated light, thereby demodulating the scattered spectrum. Through the photodetector and microwave sweeper, this embodiment can fully obtain the Brillouin scattering spectrum within a certain wavelength range.

[0107] like Figure 6The network architecture of a transmission line tower node in a multi-parameter sensing system for transmission lines is shown. The tower node includes a first wavelength division multiplexer (WDM), a second WDM, a splitter, a coupler, and a sensing and monitoring device. The first WDM receives the input from the single-mode fiber of the previous node and inputs the first carrier wave to the splitter and the second carrier wave to the WDM. The output of the splitter is connected to the input of the sensing and monitoring device and the second WDM, achieving beam splitting between the local node's input signal and the next node's input signal. The second WDM multiplexes the second carrier wave and the split first carrier wave, outputting them to the next node. Simultaneously, it receives the input from the single-mode fiber of the next node and inputs the third carrier wave and the back-shifted frequency signal of the second carrier wave to the coupler. The input of the coupler is connected to the output of the sensing and monitoring device and the second WDM, achieving coupling between the local node's output signal and the next node's output signal. The output of the coupler is connected to the first WDM, outputting the coupled signal to the previous node through the first WDM.

[0108] It is understood that in this embodiment, the tower node realizes the transmission and reception of local signals through a beam splitter and a sensing and monitoring device, and realizes the signal connection through another port of the beam splitter.

[0109] Example 3

[0110] Embodiment 3 of this disclosure introduces a multi-parameter sensing system for power transmission lines.

[0111] like Figure 7 The multi-parameter sensing system for transmission lines shown includes:

[0112] The acquisition module is used to acquire the first and second carrier waves of the substation nodes.

[0113] The extraction module is used to extract the energy of the acquired first carrier wave to obtain a third carrier wave containing the sensing signal;

[0114] The sensing module is used to extract the back frequency shift signal of the acquired second carrier, and to sense the first parameter of the transmission line based on the back frequency shift signal; and to sense the second parameter of the transmission line based on the modulation signal of the obtained third carrier.

[0115] The combination module is used to combine the first parameter and the second parameter to obtain the operation information of the transmission line;

[0116] The first carrier, the second carrier, and the third carrier are all transmitted through single-mode optical fiber; the transmission directions of the first carrier and the second carrier are the same, and the transmission direction of the third carrier is opposite.

[0117] The detailed steps are the same as those of the multi-parameter sensing method for transmission lines provided in Example 1, and will not be repeated here.

[0118] Embodiment four

[0119] Embodiment four of the present disclosure provides a computer readable storage medium.

[0120] A computer readable storage medium, having a program stored thereon, which when executed by a processor implements the steps in the power transmission line multi-parameter sensing method according to embodiment one of the present disclosure.

[0121] The detailed steps are the same as the power transmission line multi-parameter sensing method provided in embodiment one, and will not be repeated here.

[0122] Embodiment five

[0123] Embodiment five of the present disclosure provides an electronic device.

[0124] An electronic device, comprising a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor implements the steps in the power transmission line multi-parameter sensing method according to embodiment one of the present disclosure when executing the program.

[0125] The detailed steps are the same as the power transmission line multi-parameter sensing method provided in embodiment one, and will not be repeated here.

[0126] The above merely provides preferred embodiments of the present disclosure but not for limiting the present disclosure. For those skilled in the art, the present disclosure can have various modifications and changes. Any modified, equivalent replaced, improved and the like within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for power line multi-parameter sensing, the method comprising: The method comprises the following steps: acquiring a first carrier and a second carrier of a substation node; extracting the energy of the acquired first carrier to obtain a third carrier containing a sensing signal; extracting a back frequency shift signal of the acquired second carrier to sense a second parameter of the power transmission line based on the back frequency shift signal; sensing a first parameter of the power transmission line based on a modulation signal of the obtained third carrier; combining the first parameter and the second parameter to obtain operation information of the power transmission line; wherein the first carrier, the second carrier and the third carrier are all transmitted through a single-mode optical fiber; the transmission directions of the first carrier and the second carrier are consistent, and opposite to the transmission direction of the third carrier; the first carrier is used to supply power to a remote power tower; the second carrier is used to measure the stress at each position of the power transmission line; and the third carrier is used to acquire feedback of environmental information of the power tower; the optical signal of the uplink power transmission line tower in the single-mode optical fiber is demultiplexed by a first wavelength division multiplexer to realize the output of the first carrier and the second carrier, the first carrier output is sent to the receiving end of the energy storage unit of the sensing monitoring device on the downlink power transmission line tower after passing through a light splitter, the second carrier is multiplexed by a second wavelength division multiplexer and then output to the downlink power transmission line tower; the energy storage unit performs photoelectric conversion on the first carrier and realizes power supply to the sensing unit of the sensing monitoring device; the sensing unit sends the third carrier modulated with the sensing signal to the coupler to realize the combination of the third carrier output from the downlink power transmission line tower of the second wavelength division multiplexer and the back frequency shift signal of the second carrier, and then the combination is output to the uplink power transmission line tower through the first wavelength division multiplexer; if the light splitter has N light splitters in total, the light splitting ratio of the nth light splitter is at least ； wherein, is the required power of the nth sensor monitoring device, is the attenuation coefficient of the first carrier in the single-mode optical fiber is the nth power of, is the transmission distance between the tower where the ith optical splitter is located and the tower where the line above the tower is located, is the first carrier transmission power of the substation.

2. A method of power line multi-parameter sensing as claimed in claim 1, wherein, In the process of acquiring the first carrier and the second carrier of the substation node, the first carrier and the second carrier are collected based on the substation node, and the first carrier and the second carrier obtained in the substation node are transmitted to the tower of the power transmission line through the single-mode optical fiber, thereby realizing the acquisition of the first carrier and the second carrier of the substation node.

3. A method for power line multi-parameter sensing as claimed in claim 1, wherein, The first parameter at least includes environmental data, and the environmental data includes environmental wind speed, environmental wind direction, environmental air pressure, environmental temperature and environmental humidity; the second parameter is fiber strain data, and the fiber strain data depends on the size of the fiber strain and the fiber strain position corresponding to the size of the fiber strain.

4. A power line multi-parameter sensing system, characterized by, The method comprises the following steps: an acquisition module for acquiring a first carrier and a second carrier of a substation node; an extraction module for extracting the energy of the acquired first carrier to obtain a third carrier containing a sensing signal; a sensing module for extracting a back frequency shift signal of the acquired second carrier to sense a second parameter of the power transmission line based on the back frequency shift signal; and sensing a first parameter of the power transmission line based on a modulation signal of the obtained third carrier; a combination module for combining the first parameter and the second parameter to obtain operation information of the power transmission line; wherein the first carrier, the second carrier and the third carrier are all transmitted through a single-mode optical fiber; the transmission directions of the first carrier and the second carrier are consistent, and opposite to the transmission direction of the third carrier; The first carrier supplies power to the remote power tower; the second carrier measures the stress at each position of the power transmission line; and the third carrier obtains feedback of the environmental information of the power tower; The optical signal of the uplink transmission line tower in the single-mode optical fiber is demultiplexed by the first wavelength division multiplexer to realize the first carrier output and the second carrier output, the first carrier output is sent to the energy storage unit receiving end of the sensing monitoring device on the downlink transmission line tower after passing through the optical splitter, and the second carrier is multiplexed by the second wavelength division multiplexer and then output to the downlink transmission line tower; the energy storage unit performs photoelectric conversion on the first carrier and realizes power supply to the sensing unit of the sensing monitoring device; the sensing unit sends the third carrier modulated with the sensing signal to the coupler to realize the combination of the third carrier output and the back-to-frequency shift signal of the second carrier from the downlink transmission line tower, and then the combination is output to the uplink transmission line tower through the first wavelength division multiplexer; If the optical splitter has N optical splitters in total, the splitting ratio of the nth optical splitter is at least ； wherein, is the required power of the nth sensor monitoring device, is the attenuation coefficient of the first carrier in the single-mode optical fiber is the nth power of, is the transmission distance between the tower where the ith optical splitter is located and the tower where the line above the tower is located, is the first carrier transmission power of the substation.

5. A power line multi-parameter sensing system as claimed in claim 4, characterized in that, The power transmission line multi-parameter sensing system comprises a substation node, one or more power transmission line tower nodes, and a power transmission line between the nodes; wherein the substation node and the one or more power transmission line tower nodes are connected in sequence, and the power transmission line is divided into multiple sections by the multiple power transmission line tower nodes; the first carrier, the second carrier and the third carrier are transmitted in the single-mode optical fiber in each section of the multiple sections of the power transmission line.

6. A power line multi-parameter perception system as claimed in claim 5, characterized in that The substation node comprises a host, a first carrier laser, a second carrier demodulator, an optical fiber strain monitoring unit and a second wavelength division multiplexer; the first carrier laser, the second carrier demodulator and the optical fiber strain monitoring unit are connected to the single-mode optical fiber through the multiplexing ports of the second wavelength division multiplexer respectively; and the host is connected to the output ports of the second carrier demodulator and the optical fiber strain monitoring unit respectively.

7. A power line multi-parameter sensing system as claimed in claim 5, characterized in that, The power transmission line tower node comprises a first wavelength division multiplexer, a second wavelength division multiplexer, an optical splitter, a coupler and a sensing monitoring device; wherein the first wavelength division multiplexer receives the input of the single-mode optical fiber of the previous node, inputs the first carrier to the optical splitter and inputs the second carrier to the second wavelength division multiplexer; the output end of the optical splitter is connected to the input end of the sensing monitoring device and the second wavelength division multiplexer respectively; the second wavelength division multiplexer multiplexes the second carrier and the split first carrier and outputs them to the next node, simultaneously receives the input of the single-mode optical fiber of the next node, and then inputs the third carrier and the back-to-frequency shift signal of the second carrier to the coupler; and the input end of the coupler is connected to the output end of the sensing monitoring device and the second wavelength division multiplexer respectively.

8. A computer-readable storage medium having stored thereon a program, characterized in that, The program is executed by the processor to realize the steps in the power transmission line multi-parameter sensing method of any one of claims 1-3.

9. An electronic device comprising a memory, a processor, and a program stored on the memory and executable on the processor, characterized in that, The processor executes the program to realize the steps in the power transmission line multi-parameter sensing method of any one of claims 1-3.

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