Distributed photovoltaic data acquisition and transmission method and system

Abstract

A kind of distributed photovoltaic data acquisition transmission method and system, read preset transmission strategy file, obtain measuring point data and its sending frequency, minimum sending frequency, data transmission priority, and carry out data transmission according to preset transmission strategy;Signal strength of mobile communication network is obtained, and corresponding communication module is selected according to signal strength of mobile communication network to carry out data transmission;Average bandwidth of network transmission is counted, and transmission bandwidth required by current transmission strategy is calculated;Data transmission priority configuration is read, and the data set is divided in combination with network average bandwidth, and new data transmission strategy is formulated;New data transmission strategy is executed, and the data not sent is locally cached;Whether mobile communication channel is recovered is judged, and default sending configuration is restored, and local cache data is supplemented.This application reduces the problems such as data lag and loss caused by unstable network, and improves the service quality of communication link.

Description

Technical Field

[0001] This invention belongs to the field of data acquisition and transmission technology, and specifically relates to a distributed photovoltaic data acquisition and transmission method and system. Background Technology

[0002] With the introduction of the "dual carbon" policy, the country has begun to vigorously develop the construction of new energy power plants such as photovoltaic and wind power. At the same time, in order to adapt to the major trend of digital transformation of new energy power plants, various digital instruments will be used to replace traditional mechanical instruments, and data will be used to monitor and manage various operations of the power plant. Among these, data acquisition is a fundamental link in the construction of digital new energy power plants.

[0003] Distributed photovoltaic (PV) power plants mostly use string PV inverters for networking. This method can effectively reduce the fire hazards caused by DC-side faults, and also has advantages such as better environmental adaptability, more flexible component arrangement schemes, simple assembly, and easy construction. However, string PV inverters have many terminals, and when using a wired ring network for communication networking, the required communication cables are expensive, the engineering implementation is more difficult, and the maintainability is also poor.

[0004] Therefore, distributed photovoltaic (PV) systems are increasingly adopting wireless communication for networking. However, since distributed PV power plants are generally built in remote areas such as deserts, Gobi, wastelands, and plateaus, where natural conditions are harsh and communication infrastructure is weak, wireless communication is easily affected by weather, temperature, and other natural conditions, causing fluctuations in data transmission links. Traditional data acquisition and transmission methods cannot detect changes in channel conditions, thus failing to adjust the amount of data acquired and transmitted. This can lead to data volume exceeding the current channel capacity, resulting in data accumulation or even loss, severely impacting the real-time performance, reliability, and integrity of production data acquisition. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a distributed photovoltaic data acquisition and transmission method and system. By employing methods such as channel awareness, data transmission priority, adaptive transmission strategy configuration, and local data caching, it reduces data delays and loss caused by network instability, thereby improving the service quality of the communication link.

[0006] The present invention adopts the following technical solution.

[0007] A distributed photovoltaic data acquisition and transmission method includes the following steps:

[0008] Step 1: Collect the list of measurement points to be collected. Based on the actual data collection business requirements and the data transmission priority model, determine the real-time priority, data criticality, and data change frequency level of each measurement point, and calculate the transmission priority of all measurement points. Generate a preset transmission strategy file, which contains the measurement point name, transmission priority, data volume, default transmission frequency, and minimum transmission frequency for each measurement point.

[0009] Step 2: Read the preset transmission strategy file, obtain the transmission priority, data volume, default transmission frequency, and minimum transmission frequency information for each measurement point, and generate a transmission dataset. The transmission dataset includes the measurement points that actually transmit and their corresponding transmission frequencies. The first generated transmission dataset is called the default transmission dataset. The default transmission dataset contains all measurement points, and the transmission frequency of each measurement point is its default transmission frequency.

[0010] Step 3: Data transmission is performed on the measurement points in the transmitted dataset, and the adaptive acquisition and transmission mode is entered to obtain the signal strength of the mobile communication network. Based on the comparison between the signal strength of the mobile communication network and the set threshold, the corresponding communication module is selected to transmit different datasets.

[0011] Step 4: Calculate the average bandwidth B0 of the current network transmission, read the preset transmission strategy file, calculate the transmission priority range of the measurement points that the average bandwidth B0 of the current network transmission can support, generate the initial transmission dataset based on this range, and determine whether to expand the range of the transmission dataset.

[0012] Step 5: Based on the principle of maximizing the range of transmitted data, reduce the transmission frequency of some measurement points in the initially generated transmitted data set, and allocate this redundant bandwidth B... r This is used to expand the range of measurement points covered by the transmitted dataset, forming the final transmitted dataset.

[0013] Step 6: Execute the data transmission task according to the newly generated final transmission dataset, and cache the untransmitted data locally;

[0014] Step 7: By comparing the network signal strength with the first and second thresholds, determine whether the mobile communication channel has been restored. If the channel has been restored, restore the default transmission dataset and retransmit the locally cached data; if the channel has not been restored, return to step 3.

[0015] Preferably, in step 1, based on the actual data acquisition service needs, the number of transmission priorities in the data transmission priority model is defined as T, and the transmission priorities from high to low are denoted as (T, T-1, ..., 1); in addition, the data real-time priority is defined as N levels from low to high: (RT1, RT2, ..., RT...). NThe criticality of data is defined into q levels from low to high, denoted as (C1, C2, ..., C...). q The data change frequency priority is represented by the data change frequency f of the measuring point itself. We also define the data change frequency of the measuring point with the fastest data change among all the measuring points collected in this study as f_t. e The closeness of the data change frequency factor is denoted as f / f. e If, for a certain measurement point, its evaluation index level in the data transmission priority model is [RT], then... a C b ,f c If their degree of closeness to the corresponding factor is U, then their degree of closeness to the highest level is U. n =[RT a / RT N C b / C q ,f c / f e Let W be the optimal weight set, then the transmission priority number of this data is p = T·U n ·W T .

[0016] Each element in the weight set W is defined as follows:

[0017]

[0018] in, a ij To determine the elements in the matrix, the statistical averaging method is used to estimate the importance relationship between each evaluation factor, where m is the number of evaluation indicators in the data transmission priority model.

[0019] Preferably, in step 2, a preset transmission strategy file is read to obtain the transmission priority, data volume, default transmission frequency, and minimum transmission frequency information for each measurement point, and a transmission dataset is generated. The transmission dataset is the set of measurement points that the system actually transmits to, including the name of the measurement point that actually transmits to and its corresponding transmission frequency.

[0020] The first generated transmission dataset is called the default transmission dataset. The default transmission dataset contains all measurement points, and the transmission frequency of each measurement point is its default transmission frequency. In the emergency communication mode where the wireless network is interrupted and Beidou short message is used for transmission, the transmission dataset used is called the critical dataset. The critical dataset contains a small amount of necessary data related to the safety of distributed photovoltaic production, such as alarms and controls. The critical dataset is generally configured by the site operator.

[0021] Preferably, in step 3, continuously detect the signal strength of the mobile communication module. If the signal strength is greater than the first threshold T1, restore the preset data transmission configuration and retransmit the historical data cached locally to the communication master station;

[0022] If the signal strength is less than the first threshold T1 and greater than the second threshold T2, and the duration of this state is greater than the threshold t F , detect the transmission bandwidth of the current network and generate a new transmission data set according to the network conditions; otherwise, continue to execute the transmission task according to the existing transmission data set;

[0023] If the signal strength is less than the second threshold T2, enter the emergency data transmission mode and use the Beidou short message communication mode to transmit the data in the key data set.

[0024] Preferably, in step 4, use the iPerf tool to evaluate the average bandwidth B0 of the network transmission. At the same time, according to the measurement point transmission priority, data volume and default transmission frequency in the preset transmission configuration file, calculate the priority range P of the measurement points that can be transmitted by the average bandwidth B0;

[0025] Suppose the calculated transmission priority range covered by the transmission data set is P = [T, p n , where T is the highest priority, and let P1 represent the set of all measurement points in the transmission priority stage where p n is located. At the same time, let p m = , where represents the ceiling operation on x, and p m represents the previous integer transmission priority of p n Calculate the proportion ρ of the data volume covered by the priority range P0 = [P m , P n to the total data volume of the P1 priority, and judge whether ρ is greater than the preset threshold t;

[0026] If ρ < t, only take the data within the range of [T, p m and divide it into the transmission data set. The transmission frequency of each data in the transmission data set is the same as the transmission frequency in the preset transmission configuration;

[0027] If ρ ≥ t, first divide P = [T, p n into the transmission data set, and then, according to the principle of maximizing the transmission data set, appropriately reduce the transmission frequency of the data within the priority range P0 = [p m , p n , and allocate the redundant transmission bandwidth to other measurement points with a transmission priority within the range of P k to expand the transmission data and range, where P k=P1-P0.

[0028] Preferably, in step 5, the expansion of the measurement point range covered by the transmitted dataset to form the final transmitted dataset is as follows:

[0029] Step 5.1: Modify P0 = [p m ,p n The collection frequency of all data within this priority range is reduced to the lowest collection frequency f specified in the preset configuration file for that data. min And calculate the redundant transmission bandwidth B r ;

[0030] Step 5.2: Let ,in p represents rounding down. r Then it is p n The next integer transmission priority; for P k =[p n ,p r Within this priority range, the measurement points can be used through redundant bandwidth B based on their lowest transmission frequency. r The transmission priority range P of the measurement points to be transmitted r =[p n ,p n' ], where p n' To pass B r The transmission priority of the last measurement point that can be sent additionally;

[0031] Step 5.3: Compare p n' and p r The size of p n' ≤p r Then the dataset to be sent is determined to be F = [T, p n' ];

[0032] If p n' >p r Then the dataset to be sent is determined to be F = [T, p r ] Calculate the remaining bandwidth B r' And from priority p m Initially, data acquisition frequencies are restored to the default frequency in descending order of priority, until the newly added transmission bandwidth equals the redundant bandwidth B. r' until;

[0033] Step 5.4: Generate the final transmission dataset based on the transmission data priority range and its acquisition frequency determined in steps 5.1 to 5.3.

[0034] A distributed photovoltaic data acquisition and transmission system includes a main control module, a transmission strategy configuration module, a channel status sensing module, a data retransmission module, a data buffer module, a data acquisition module, and a data transmission module.

[0035] The main control module is connected to the data acquisition service, data caching service, data retransmission service, transmission strategy configuration service, channel state awareness service, and data buffer. It is mainly responsible for controlling the behavior of each module, responding to the signals of each sub-module, parsing the data transmission strategy configuration file, and adjusting the workflow of each system according to the transmission strategy to ensure the orderly operation of the entire system.

[0036] The main functions of the data acquisition module are to communicate with the data source device and collect production data; to parse the communication messages, extract the data from the messages, and encapsulate the collected data into a common data format before writing it into the data transmission buffer;

[0037] The data caching module is designed to cache data that has not yet been transmitted locally as files and manage these cached files.

[0038] After receiving instructions from the main control module, the data retransmission module will acquire and parse the cache file, convert the historical data in the file into the transmission data format, and then create a data retransmission channel through the data sending module to retransmit the historical data that was not transmitted in time.

[0039] The function of the channel state sensing module is to sense the channel state of the mobile communication module, obtain channel information such as mobile signal strength and real-time transmission rate, and calculate the channel transmission capacity.

[0040] The function of the transmission strategy configuration module is to adaptively adjust the data range in the transmission dataset according to the current channel state and data transmission priority, match the amount of data to be transmitted with the current channel state, and then generate the corresponding transmission strategy configuration file.

[0041] The main function of the data transmission module is to activate the corresponding data transmission channel according to the control logic of the main control module and transmit the data to the communication master station.

[0042] The beneficial effects of this invention are that, compared with the prior art, this invention, through channel sensing, data transmission priority, and adaptive transmission strategy configuration, can sense the real-time link bandwidth of the communication channel when fluctuations occur in the communication channel of the acquisition device, and can adaptively and intelligently adjust the configuration of the acquired and transmitted data (such as the data set, data volume, and transmission frequency) according to the estimated real-time link bandwidth and the priority of transmitted data. This ensures that the amount of real-time data transmitted matches the current channel capacity, and at the same time, prioritizes the allocation of channel resources to production real-time data with high transmission priority, improves the service quality of channel resources, and prevents the accumulation of critical production data due to network congestion, which could lead to update delays or loss. This ensures the normal operation of various production services in the distributed site. Attached Figure Description

[0043] Figure 1 This is a flowchart of a distributed photovoltaic data acquisition and transmission method according to the present invention;

[0044] Figure 2 This is a schematic diagram of the specific process of a distributed photovoltaic data acquisition and transmission method in an embodiment of the present invention;

[0045] Figure 3 This is a flowchart illustrating the process of determining a data transmission strategy in an embodiment of the present invention;

[0046] Figure 4 This is a schematic diagram illustrating the range of each data set before and after dividing the data set for sending in an embodiment of the present invention;

[0047] Figure 5 This is a schematic diagram of the structure of a distributed photovoltaic data acquisition and transmission system according to the present invention. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0049] A distributed photovoltaic data acquisition and transmission method, such as Figure 1 As shown, the specific steps include:

[0050] Step 1: Collect the list of measurement points to be collected. Based on the actual data collection business requirements and the data transmission priority model, determine the real-time priority, data criticality, and data change frequency level of each measurement point, and calculate the transmission priority of all measurement points. Generate a preset transmission strategy file, which contains the measurement point name, transmission priority, data volume, default transmission frequency, and minimum transmission frequency for each measurement point.

[0051] Suppose that, based on actual business needs, the number of transmission priorities in the data transmission priority model is T, and the transmission priorities from high to low are denoted as (T, T-1, ..., 1); in addition, the data real-time priority is defined as N levels from low to high: (RT1, RT2, ..., RT...). N The criticality of data is defined into q levels from low to high: (C1, C2, ..., C...). q The data change frequency priority is represented by the data change frequency f of the measuring point itself. We also define the data change frequency of the measuring point with the fastest data change among all the measuring points collected in this study as f_t. e The closeness of the data change frequency factor is denoted as f / f. e If, for a certain measurement point, its evaluation index level in the data transmission priority model is [RT], then... a C b ,f c If their degree of closeness to the corresponding factor is U, then their degree of closeness to the highest level is U. n =[RT a / RT N C b / C q ,f c / f e Let W be the optimal weight set, then the transmission priority number of this data is p = T·U n ·W T .

[0052] The weight set W can be determined using a combination of analytic hierarchy process (AHP) and expert decision-making. The specific steps are as follows:

[0053] First, using the expert decision-making method, the experience, knowledge, and subjective judgment of experts and relevant business personnel are utilized. The statistical averaging method is then used to estimate the importance relationships between various evaluation factors, and based on this, a judgment matrix A = (a ij ) n×n The rules for constructing the matrix are shown in the table below:

[0054]

[0055] After establishing the judgment matrix A, normalize A as follows:

[0056]

[0057] Based on the normalization matrix Calculate each element in the weight set W, where m is the number of evaluation factors in the data transmission priority model:

[0058]

[0059] Finally, the transmission priority of all data can be calculated using the following formula:

[0060] p = T·U n ·W T

[0061] After calculating the transmission priority of all measurement points, a preset transmission strategy file is generated. This file contains the data name, transmission priority, data size, default transmission frequency, and minimum transmission frequency for each measurement point. The minimum transmission frequency indicates the lowest acceptable data update frequency for a given measurement point when network anomalies or congestion necessitate reducing the data transmission frequency.

[0062] Step 2: The main control service reads the preset data transmission configuration file, obtains the transmission priority, data volume, default transmission frequency, and minimum transmission frequency information for each measurement point, and generates a transmission dataset. The transmission dataset is the set of measurement points that the system actually transmits data to, including the names of the measurement points that actually transmit data and their corresponding transmission frequencies.

[0063] The first generated transmission dataset is called the default transmission dataset. The default transmission dataset contains all measurement points, and the transmission frequency of each measurement point is its default transmission frequency. In the emergency communication mode where the wireless network is interrupted and Beidou short message is used for transmission, the transmission dataset used is called the critical dataset. The critical dataset contains a small amount of necessary data related to the safety of distributed photovoltaic production, such as alarms and controls. The critical dataset is generally configured by the site operator.

[0064] The master control service filters the data collected by the data acquisition service based on the data to be sent, and sends the data into the sending buffer according to the corresponding data sending frequency.

[0065] Step 3: Obtain the signal strength of the mobile communication network, and select the appropriate communication module for data transmission based on the signal strength of the mobile communication network.

[0066] Continuously monitor the signal strength of the mobile communication module, such as Figure 2 As shown, if the signal strength is greater than the first threshold T1, the default transmission dataset is used for transmission, and the locally cached historical data is retransmitted to the communication master station.

[0067] If the signal strength is less than the first threshold T1 and greater than the second threshold T2, and the duration of this state is greater than the threshold t... F If the network bandwidth is not found, a new transmission dataset is generated based on the network conditions; otherwise, the transmission task continues to be executed according to the existing transmission dataset.

[0068] If the signal strength is less than the second threshold T2, the emergency data transmission mode is entered, and the Beidou short message communication mode is used to transmit the data in the critical data set.

[0069] The steps for transmitting critical datasets using BeiDou short message communication mode are as follows:

[0070] Data from critical datasets such as alarms, control data, and necessary measurement points are placed in the data buffer, while data from other non-critical datasets is stopped from transmission and sent to the data cache module for local caching.

[0071] The data in the data buffer is encapsulated into BeiDou data frames and transmitted to the communication master station using the BeiDou short message communication module, and the corresponding control information is received.

[0072] Step 4: Use the iPerf tool to evaluate the average bandwidth B0 of the network transmission. At the same time, calculate the priority range P of the test points that can be transmitted by the average bandwidth B0 according to the test point transmission priority, data volume and default transmission frequency in the preset transmission configuration file.

[0073] First, the system can create a new process to execute the iPerf program. To simulate real network transmission, a test method for transferring files to a target IP address can be used. Specifically, the following commands can be executed within the process:

[0074] iperf3 -c{ip} -F{Filename} -i{T i}-t{T l};

[0075] Where {ip} is the IP address of the communication master station, {Filename} is the file used for test transmission, and {T i} represents the time interval for uploading test results, {T l} indicates the duration of the transmission test.

[0076] Then, take the average of the results of multiple tests within a certain test period and set it as the estimated value B0 of the equivalent bandwidth of the current link.

[0077] Furthermore, the transmission policy configuration service reads the current transmission dataset and uses the following formula to calculate the equivalent transmission bandwidth B required for the current transmission. c Make an estimate:

[0078]

[0079] Wherein, D i represents the data volume corresponding to the i-th measurement point during transmission, and t i represents the transmission frequency of the i-th measurement point, where i = 1, 2,..., n, and n is the number of measurement points in the current transmission dataset.

[0080] Compare the size relationship between the transmission bandwidth B c required by the current transmission strategy and the statistical average bandwidth B0. If |B c - B0| > δ, then re-determine the transmission dataset to adapt to the change of the channel. Otherwise, keep the current transmission dataset unchanged.

[0081] Calculate the range of the transmission dataset that can be supported by the current link equivalent bandwidth B0 according to the following formula:

[0082]

[0083] Wherein, θ is the number of measurement points supported for transmission, and max{x} represents the maximum number of measurement points that can be supported for transmission with the transmission bandwidth less than the link equivalent bandwidth B0 in descending order of data transmission priority.

[0084] As Figure 4 shown, suppose the range of the transmission priority covered by the calculated transmission dataset is P = [T, p n , where T is the highest priority. Let P1 represent the set of all measurement points with the transmission priority where p n is located. At the same time, let , where represents the ceiling operation on x, and p m represents p n 's previous integer transmission priority. Calculate the proportion ρ of the number of measurement points covered by the priority range P0 = [p m , p n to the total number of measurement points with this priority in P1, and determine whether ρ is greater than the preset threshold t.

[0085] If ρ < t, then only take the data within the range [T, p m and divide it into the transmission dataset. The transmission frequencies of each data in the transmission dataset are consistent with the transmission frequencies in the preset transmission configuration.

[0086] If ρ ≥ t, then first divide P = [T, p n into the transmission dataset, and then, according to the principle of maximizing the transmission dataset, for P0 = [p m , p nThe data transmission frequency within this priority range is appropriately reduced, and the redundant transmission bandwidth is allocated to the transmission priority P. k Other measurement points within the range, to expand the data transmission range, where P k =P1-P0.

[0087] Step 5: Based on the principle of maximizing the range of transmitted data, reduce the transmission frequency of some measurement points in the generated transmitted data set, and utilize the redundant transmission bandwidth B. r Assign it to other data and expand the range of measurement points covered by the sent dataset.

[0088] Step 5.1: Modify P0 = P0 = [p m ,p n The collection frequency of all data within this priority range is reduced to the lowest collection frequency f of that data in the preset configuration. min And calculate the redundant transmission bandwidth B r ;

[0089] Step 5.2: Let ,in p represents rounding down. r Then it is p n The next integer transmission priority. For P k =[p n ,p r Within this priority range, the measurement points can be used through redundant bandwidth B based on their lowest transmission frequency. r The transmission priority range P of the measurement points to be transmitted r =[p n ,p n' ], where p n' To pass B r The transmission priority of the last measurement point that can be sent additionally.

[0090] Step 5.3: Compare p n' and p r The size of p n' ≤p r Then the dataset to be sent is determined to be F = [T, p n' ];

[0091] If p n' >p r Then the dataset to be sent is determined to be F = [T, p r ] Calculate the remaining bandwidth B r' And from priority p m Initially, data acquisition frequencies are restored to the default frequency in descending order of priority, until the newly added transmission bandwidth equals the redundant bandwidth B. r'until;

[0092] Step 5.4: Generate a new transmission dataset based on the transmission data priority range and its acquisition frequency determined in steps 5.1 to 5.3.

[0093] like Figure 4 The diagram shows the different datasets before and after the dataset was divided for transmission.

[0094] Step 6: Perform data transmission tasks based on the new data set to be sent, and cache the unsent data locally.

[0095] The system will read the newly generated transmission dataset and, according to the transmission dataset in the configuration file, send the real-time data of the corresponding measurement points collected by the acquisition service into the system's transmission buffer at the configured transmission frequency. For data that is not sent into the transmission buffer, it will be sent to the data caching service for local caching in the form of files.

[0096] Step 7: Determine if the mobile communication channel has been restored, restore the default sending configuration, and retransmit the locally cached data.

[0097] Furthermore, the strength of the mobile communication signal is used to determine whether the communication channel has been restored. If the current communication signal strength is greater than the first threshold T1, the data retransmission service is started to retransmit the historical data that has not been sent in the local cache file to the communication master station, and the sending dataset is restored to the default sending dataset for full data transmission; otherwise, the process returns to step 3 to reselect the transmission mode.

[0098] A distributed photovoltaic data acquisition and transmission system, such as Figure 5 As shown, it includes a main control module, a transmission strategy configuration module, a channel state awareness module, a data retransmission module, a data buffer module, a data acquisition module, and a data transmission module.

[0099] The main control module is connected to the data acquisition service, data caching service, data retransmission service, transmission strategy configuration service, channel status awareness service, and data buffer. It is mainly responsible for controlling the behavior of each module, responding to signals from each sub-module, parsing the data transmission strategy configuration file, and adjusting the workflow of each system according to the transmission strategy to ensure the orderly operation of the entire system.

[0100] The main functions of the data acquisition module are to communicate with the data source device and collect production data; to parse the communication messages, extract the data from the messages, and encapsulate the collected data into a common data format before writing it into the data transmission buffer.

[0101] The data caching module is designed to cache data that has not been transmitted locally as files and manage the data cache files.

[0102] After receiving instructions from the main control module, the data retransmission module will acquire and parse the cache file, convert the historical data in the file into the transmission data format, and then create a data retransmission channel through the data sending module to retransmit the historical data that was not transmitted in time.

[0103] The function of the channel state sensing module is to sense the channel state of the mobile communication module, obtain channel information such as mobile signal strength and real-time transmission rate, and calculate the channel transmission capacity.

[0104] The function of the transmission strategy configuration module is to adaptively adjust the data range in the transmission dataset according to the current channel state and data transmission priority, match the amount of data to be transmitted with the current channel state, and then generate the corresponding transmission strategy configuration file.

[0105] The main function of the data transmission module is to activate the corresponding data transmission channel according to the control logic of the main control module and transmit the data to the communication master station.

[0106] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0107] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0108] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0109] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A distributed photovoltaic data acquisition and transmission method, characterized in that, Includes the following steps: Step 1: Collect the list of measurement points to be collected. Based on the actual data collection business requirements and the data transmission priority model, determine the real-time priority, data criticality, and data change frequency level of each measurement point. Calculate the transmission priority of all measurement points and generate a preset transmission strategy file. The file contains the measurement point name, transmission priority, data volume, default transmission frequency, and minimum transmission frequency for each measurement point. Step 2: Read the preset transmission strategy file, obtain the transmission priority, data volume, default transmission frequency, and minimum transmission frequency information for each measurement point, and generate a transmission dataset. The transmission dataset includes the measurement points that actually transmit and their corresponding transmission frequencies. The first generated transmission dataset is called the default transmission dataset. The default transmission dataset contains all measurement points, and the transmission frequency of each measurement point is its default transmission frequency. Step 3: Data transmission is performed on the measurement points in the transmitted dataset, and the adaptive acquisition and transmission mode is entered to obtain the signal strength of the mobile communication network. Based on the comparison between the signal strength of the mobile communication network and the set threshold, the corresponding communication module is selected to transmit different datasets. Step 4: Calculate the average bandwidth B0 of the current network transmission, read the preset transmission strategy file, calculate the transmission priority range of the measurement points that the average bandwidth B0 of the current network transmission can support, generate the initial transmission dataset based on this range, and determine whether to expand the range of the transmission dataset. In step 4, the iPerf tool is used to evaluate the average bandwidth B0 of the network transmission. At the same time, based on the transmission priority of the measurement points, the amount of data and the default transmission frequency in the preset transmission configuration file, the priority range P of the measurement points that can be transmitted by the average bandwidth B0 is calculated. The calculated transmission priority range for the measurement points covered by the transmitted dataset is P = [T, p]. n ], where T is the highest priority, and let P1 represent p n The set of all measurement points in the current transmission priority phase, and simultaneously let in p represents the floor function of x. m p n The previous integer transmission priority is used to calculate P0 = [P m ,P n The proportion ρ of the data covered by this priority range to the total data volume of priority P1 is determined, and it is determined whether ρ is greater than the preset threshold t. If ρ < t, only the data within [T, p m is divided into the sending data set, and the sending frequency of each data in the sending data set is consistent with the sending frequency in the preset sending configuration; if ρ ≥ t, first divide P = [T, p n into the sending data set, and then, according to the principle of maximizing the sending data set, appropriately reduce the sending frequency of the data within the priority range of P0 = [p m , p n , and allocate the redundant transmission bandwidth to other measurement points with a transmission priority of P k to expand the sending data range, where P k = P1 - P0; Step 5: Based on the principle of maximizing the range of transmitted data, reduce the transmission frequency of some measurement points in the initially generated transmitted data set, and allocate this redundant bandwidth B... r Used to expand the range of measurement points covered by the transmitted dataset, forming the final transmitted dataset; Step 5.1: Modify P0 = [p m ,p n The collection frequency of all data within this priority range is reduced to the lowest collection frequency f specified in the preset configuration file for that data. min And calculate the redundant transmission bandwidth B r ; Step 5.2: Let in p represents rounding down. r Then it is p n The next integer transmission priority; for P k =[p n ,p r Within this priority range, the measurement points can be used through redundant bandwidth B based on their lowest transmission frequency. r The transmission priority range P of the measurement points to be transmitted r =[p n ,p n′ ], where p n′ To pass B r The transmission priority of the last measurement point that can be sent additionally; Step 5.3: Compare p n′ and p r The size of p n′ ≤p r Then the dataset to be sent is determined to be F = [T, p n′ ]; If p n′ >p r Then the dataset to be sent is determined to be F = [T, p r ] Calculate the remaining bandwidth B r ′, and from priority p m Initially, data acquisition frequencies are restored to the default frequency in descending order of priority, until the newly added transmission bandwidth equals the redundant bandwidth B. r′ until; Step 5.4: Generate the final transmission dataset based on the transmission data priority range and its acquisition frequency determined in steps 5.1 to 5.3; Step 6: Execute the data transmission task according to the newly generated final transmission dataset, and cache the untransmitted data locally; Step 7: By comparing the network signal strength with the first and second thresholds, determine whether the mobile communication channel has been restored. If the channel has been restored, restore the default transmission dataset and retransmit the locally cached data; if the channel has not been restored, return to step 3.

2. The distributed photovoltaic data acquisition and transmission method according to claim 1, characterized in that: In step 1, based on the actual data acquisition needs, the number of transmission priorities in the data transmission priority model is defined as T, and the transmission priorities from high to low are denoted as (T, T-1, ..., 1); in addition, the data real-time priority is defined as N levels from low to high: (RT1, RT2, ..., RT...). N The criticality of data is defined into q levels from low to high, denoted as (C1, C2, ..., C...). q The data change frequency priority is represented by the data change frequency f of the measuring point itself. We also define the data change frequency of the measuring point with the fastest data change among all the measuring points collected in this study as f_t. e The closeness of the data change frequency factor is denoted as f / f. e If, for a certain measurement point, its evaluation index level in the data transmission priority model is [RT], then... a C b ,f c If their degree of closeness to the corresponding factor is U, then their degree of closeness to the highest level is U. n =[RT a / RT N C b / C q ,f c / f e Let W be the optimal weight set, then the transmission priority number of this data is p = T·U n ·W T .

3. The distributed photovoltaic data acquisition and transmission method according to claim 2, characterized in that: Each element in the weight set W is defined as follows: in, a ij To determine the elements in the matrix, the statistical averaging method is used to estimate the importance relationship between each evaluation factor, where m is the number of evaluation indicators in the data transmission priority model.

4. The distributed photovoltaic data acquisition and transmission method according to claim 1, characterized in that: In step 2, the preset transmission strategy file is read to obtain the transmission priority, data volume, default transmission frequency, and minimum transmission frequency information for each measurement point, and a transmission dataset is generated. The transmission dataset is the set of measurement points that the system actually transmits to, including the name of the measurement point that actually transmits to and its corresponding transmission frequency. The first generated transmission dataset is called the default transmission dataset. The default transmission dataset contains all measurement points, and the transmission frequency of each measurement point is its default transmission frequency. In the emergency communication mode where the wireless network is interrupted and Beidou short message is used for transmission, the transmission dataset used is called the critical dataset. The critical dataset contains a small amount of necessary data related to the safety of distributed photovoltaic production, such as alarms and controls. The critical dataset is generally configured by the site operator.

5. The distributed photovoltaic data acquisition and transmission method according to claim 1, characterized in that: In step 3, the signal strength of the mobile communication module is continuously detected. If the signal strength is greater than the first threshold T1, the preset data transmission configuration is restored and the historical data cached locally is retransmitted to the communication master station. If the signal strength is less than the first threshold T1 and greater than the second threshold T2, and the duration of this state is greater than the threshold t... F The system detects the current network bandwidth and generates a new transmission dataset based on the network conditions; otherwise, it continues to perform the transmission task according to the existing transmission dataset. If the signal strength is less than the second threshold T2, the emergency data transmission mode is entered, and the Beidou short message communication mode is used to transmit the data in the critical data set.

6. A distributed photovoltaic data acquisition and transmission system, used to implement the distributed photovoltaic data acquisition and transmission method according to any one of claims 1-5, comprising a main control module, a transmission strategy configuration module, a channel state awareness module, a data retransmission module, a data buffer module, a data acquisition module, and a data transmission module, characterized in that: The main control module is connected to the data acquisition service, data caching service, data retransmission service, transmission strategy configuration service, channel state awareness service, and data buffer. It is mainly responsible for controlling the behavior of each module, responding to the signals of each sub-module, parsing the data transmission strategy configuration file, and adjusting the workflow of each system according to the transmission strategy to ensure the orderly operation of the entire system. The main function of the data acquisition module is to communicate with the data source device and collect production data; The communication message is parsed, the data in the message is extracted, and the collected data is encapsulated into a common data format and written into the data transmission buffer. The data caching module is designed to cache data that has not yet been transmitted locally as files and manage these cached files. After receiving the instruction from the main control module, the data retransmission module will acquire and parse the cache file, convert the historical data in the file into the transmission data format, and then create a data retransmission channel through the data sending module to retransmit the historical data that was not transmitted in time. The function of the channel state sensing module is to sense the channel state of the mobile communication module, obtain channel information such as mobile signal strength and real-time transmission rate, and calculate the transmission capacity of the channel. The function of the transmission strategy configuration module is to adaptively adjust the data range in the transmission dataset according to the current channel state and data transmission priority, match the amount of data to be transmitted with the current channel state, and then generate the corresponding transmission strategy configuration file. The main function of the data transmission module is to activate the corresponding data transmission channel according to the control logic of the main control module and transmit the data to the communication master station.

7. A terminal, comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method according to any one of claims 1-5.

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