Power distribution terminal communication optimization method and system based on Beidou short message

Abstract

The invention discloses a Beidou short message-based power distribution terminal communication optimization method and system, and the method is applied to a Beidou short message-based power distribution automation system, a Beidou communication module obtains a response message of a power distribution automation terminal, sets the highest priority for a remote control message, reports the remote control message in real time, shields a frequent displacement message for a remote signaling message, and carries out the real-time monitoring of the remote signaling message. Key information is extracted from the remaining remote signaling messages, protocol conversion is carried out according to a private protocol, then the messages are reported, and the telemetering messages are reported through total calling and important remote signaling deflection triggering; the data is compressed and numbered before being reported, so that channel blockage and message loss are avoided; and the Beidou short message communication manager obtains a remote control instruction of the power distribution automation master station, directly responds to a corresponding message to the power distribution automation master station if the remote control instruction is a remote control selection instruction or a remote control revocation instruction, directly issues the corresponding message if the remote control instruction is a remote control execution instruction, and starts a retransmission mechanism if the remote control execution confirmation message is overtime. According to the invention, the integrity and reliability of data transmission are systematically improved.

Description

A method and system for optimizing power distribution terminal communication based on BeiDou short message service. Technical Field

[0001] This invention relates to power system distribution automation communication technology, specifically to a method and system for optimizing distribution terminal communication based on BeiDou short message service. Background Technology

[0002] Currently, power distribution automation terminals based on public mobile networks suffer from signal coverage blind spots due to geographical limitations, severely impacting the real-time performance and reliability of remote data transmission. BeiDou short message communication, a unique two-way message service of my country's BeiDou satellite navigation system, offers advantages such as wide-area coverage, no ground blind spots, and lower cost. It is particularly suitable for remote areas without public network signals, providing effective communication supplementation between power distribution terminals and the main station, thereby resolving the bottleneck problem in data transmission.

[0003] Figure 1 illustrates the architecture of a distribution automation system based on BeiDou short message service, including the field side and the master station side. The field side consists of distribution automation terminals, BeiDou communication modules, and BeiDou-3 data transmission terminals, responsible for collecting and transmitting distribution data. The master station side includes BeiDou-3 data transmission terminals, a BeiDou communication management unit, and the distribution automation system, responsible for receiving and processing data and issuing control commands. The system achieves two-way satellite communication through a BeiDou RDSS antenna, making it suitable for distribution automation services in areas without public network coverage.

[0004] During the operation of distribution automation systems, terminal equipment continuously generates a large amount of remote signaling and telemetry data. Distribution terminals based on BeiDou short message communication are highly susceptible to communication channel congestion if they experience frequent changes in remote signaling or sudden changes in telemetry data. Currently, the maximum single-transmission capacity of BeiDou Level 2 communication cards used in the power industry is only 229 bytes, with a transmission interval of no less than 60 seconds. Under the influence of multiple factors such as limited channel resources and severe weather interference, data packet loss occurs frequently, resulting in the loss of important remote signaling information and failure to transmit remote control commands, making it difficult to meet the requirements of distribution systems for real-time monitoring and high-reliability communication. Test data shows that even under normal conditions, the packet loss rate is only about 1%, but the massive amount of data generated in a short period during a distribution network fault will still cause a delay of 4-5 minutes in information upload, severely hindering rapid fault location and handling. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a method and system for optimizing communication of power distribution terminals based on Beidou short messages, which systematically improves the integrity and reliability of data transmission by preprocessing the data at the sending end, verifying the integrity of the receiving end, and designing retransmission for key services.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a method for optimizing communication of distribution terminals based on BeiDou short messages. The method is applied to a distribution automation system, which includes a distribution automation master station and a BeiDou short message communication management unit interconnected on the master station side, and distribution automation terminals and BeiDou communication modules interconnected on the field side. The BeiDou short message communication management unit and the BeiDou communication module interact via BeiDou short messages. The method includes the following steps: the BeiDou communication module obtains and parses the response messages from the distribution automation terminal; if it is a remote control message, it sets the highest priority and adds it to the data stream to be sent; if it is a remote signaling message, it blocks frequently changing remote signaling messages, extracts key information from the remaining remote signaling messages, performs protocol conversion according to a private protocol, and then adds it to the data stream. The data stream to be sent is added to the data stream if it is a telemetry message. The telemetry message includes telemetry data from periodic general calls or telemetry data triggered by important telemetry changes. Then, the data stream to be sent is compressed to generate a BeiDou short message and sent to the BeiDou short message communication management unit. The BeiDou short message communication management unit obtains the BeiDou short message data stream from the BeiDou communication module, restores the data, and reports it to the distribution automation master station. The distribution automation master station issues a remote control command. The BeiDou short message communication management unit obtains and parses the remote control command. If it is a remote control selection command or a remote control cancellation command, it directly responds to the distribution automation master station with the corresponding message. If it is a remote control execution command, it sends the remote control execution command to the distribution automation terminal through the BeiDou communication module and waits for the remote control execution confirmation message. If the timeout occurs, the retransmission mechanism is initiated.

[0007] Furthermore, when extracting key information from the remote signaling messages and performing protocol conversion according to the private protocol, the specific steps include: identifying the remote signaling address, SOE time, and remote signaling status value as key information from each remote signaling data message; sequentially arranging the key information of each remote signaling data message to construct a data body; starting from the key information corresponding to the second remote signaling data message in the data body, updating the SOE time in the key information to a relative time relative to the SOE time of the first remote signaling data message in the data body; adding the frame header information and data body length information of the private protocol to the data body to obtain the converted data frame.

[0008] Furthermore, when the BeiDou short message communication management unit acquires the BeiDou short message data stream from the BeiDou communication module and performs data restoration, it includes the steps of data reception and decompression. Specifically, it includes: parsing the data body from the message after remote signaling data protocol conversion; extracting the remote signaling address, SOE time, and remote signaling status value corresponding to each remote signaling data message from the data body; restoring the original SOE information based on the remote signaling address, SOE time, and remote signaling status value; and then converting the SOE information to generate COS information, thereby reconstructing each protocol-converted remote signaling data message into a standard protocol message.

[0009] Furthermore, when frequently changing remote signaling messages are blocked, and the remaining remote signaling messages are extracted for key information, converted according to a private protocol, and added to the data stream to be sent, the specific steps include: detecting the communication environment and message data volume; if there is a risk of channel congestion or the message data volume exceeds the carrying capacity of a single BeiDou short message, counting the number of remote signaling messages generated by the same remote signaling point; if the number of remote signaling messages generated by the same remote signaling point in a single call cycle is less than a specified value, extracting key information from all remote signaling messages, converting according to a private protocol, and adding them to the data stream to be sent; if the number of remote signaling messages generated by the same remote signaling point in a single call cycle is less than a specified value, extracting key information from all remote signaling messages, converting according to a private protocol, and adding them to the data stream to be sent; if the number of remote signaling messages generated by the same remote signaling point in a single call cycle is less than a specified value, then... If the number of messages exceeds a specified value, then the remote signaling messages after the specified number of changes of the remote signaling point are blocked. The system waits for the general call period to arrive, extracts key information from the unblocked remote signaling messages, performs protocol conversion according to the private protocol, adds them to the data stream to be sent, and then releases the blocked remote signaling messages. If the number of remote signaling messages generated by the remote signaling point in a single general call period still exceeds a specified value, after the next general call period arrives, a specified number of remote signaling messages are selected from the released remote signaling messages. The key information of the selected remote signaling messages is extracted, performs protocol conversion according to the private protocol, adds them to the data stream to be sent, and the remaining released remote signaling messages are blocked.

[0010] Furthermore, when selecting a specified number of remote communication messages from the released remote communication messages, the specific selection is made according to the chronological order of the released messages.

[0011] Furthermore, when compressing the data stream to be sent to generate BeiDou short messages, the process includes: if the total length of the data to be sent exceeds the maximum capacity of a single BeiDou short message packet, the data to be sent is divided into blocks according to the maximum capacity of a single BeiDou short message packet to obtain multiple data frames; if the total length of the data to be sent does not exceed the maximum capacity of a single BeiDou short message packet, the data to be sent is treated as a single data frame; a unique sequence number is assigned to each data frame, and each sequence number is combined with the corresponding data frame, a private protocol header is added to its header, and a checksum is added to its tail to form an encapsulated application layer data packet; the application layer data packet is sent to the BeiDou short message communication management unit, and the sent data is simultaneously buffered.

[0012] Furthermore, when the BeiDou short message communication management unit acquires the BeiDou short message data stream from the BeiDou communication module and performs data restoration, it also includes steps of missing packet checking and supplementary acquisition. Specifically, this includes: acquiring application layer data packets, parsing the total number of frames and the corresponding sequence number in the protocol header of each application layer data packet; querying the receiving status table of the distribution automation terminal to obtain the expected sequence number and the bitmap of the received frames; comparing the sequence number with the expected sequence number; if the sequence number is equal to the expected sequence number, then accepting the data in the corresponding application layer data packet and updating the bitmap, while incrementing the expected sequence number by one; if the sequence number is greater than the expected sequence number, then confirming the sequence number of the missing packet based on the value between the sequence number and the expected sequence number, generating a corresponding supplementary acquisition request, and sending it to the BeiDou communication module. After receiving the supplementary acquisition request, the BeiDou communication module extracts the corresponding data from the sent buffer and resends it to the BeiDou short message communication management unit.

[0013] Furthermore, if it is a remote control selection command or a remote control cancellation command, the corresponding message is directly sent to the distribution automation master station. Specifically, if it is a remote control selection command, the corresponding status value is queried from the pre-stored remote signaling table of the distribution automation terminal. If it is a remote status value, a remote control selection affirmative message is directly sent to the distribution automation master station. If it is a local status value, a remote control selection negative message is directly sent to the distribution automation master station. If it is a remote control cancellation command, a remote control cancellation confirmation message is directly sent to the distribution automation master station.

[0014] Furthermore, when the remote control execution command is sent to the distribution automation terminal via the Beidou communication module and a remote control execution confirmation message is awaited, and the retransmission mechanism is initiated after a timeout, the following steps are included: encapsulating the remote control execution command into a data frame of a private protocol, caching the data frame of the current remote control execution command, and then sending the data frame to the distribution automation terminal via the Beidou communication module. After the data frame is sent, a corresponding retransmission timer is started, waiting for the distribution automation terminal to return a confirmation frame via the Beidou communication module; if a correct confirmation frame is received and the retransmission timer has not timed out, the remote control is determined to be successful, the retransmission timer is closed, and the cached data frame of the current remote control execution command is cleared; if a correct confirmation frame is not received and the retransmission timer times out, the cached data frame of the current remote control execution command is sent to the distribution automation terminal via the Beidou communication module. After the data frame is sent, a corresponding retransmission timer is started, and the terminal waits again for a confirmation frame returned via the Beidou communication module. If the maximum number of retransmissions is reached and a correct confirmation frame is still not received, the remote control is determined to be unsuccessful, and the cached data frame of the current remote control execution command is cleared.

[0015] The present invention also proposes a power distribution automation system, which includes a power distribution automation master station and a Beidou short message communication management unit interconnected on the master station side, and a power distribution automation terminal and a Beidou communication module interconnected on the field side. The Beidou short message communication management unit and the Beidou communication module interact through Beidou short messages. The power distribution automation system is programmed or configured to execute the steps of the power distribution terminal communication optimization method based on Beidou short messages.

[0016] Compared with the prior art, the advantages of the present invention are as follows: The present invention sets the highest priority for remote control messages, ensuring that critical control commands are transmitted preferentially in the bandwidth-limited BeiDou short message channel, avoiding being blocked by conventional data; it performs reduction conversion on remote signaling messages to achieve semantic-level efficient compression, improve the effective payload of a single message, solve the problem of low transmission efficiency caused by redundancy of reduction messages, and shields frequently changing remote signaling messages, effectively shielding a large amount of useless data transmission and avoiding channel congestion and communication delays.

[0017] This invention employs a mechanism combining "periodic general call + triggered upload" to ensure that telemetry data is refreshed periodically without occupying excessive data space, while also ensuring that refreshed telemetry data can be uploaded in a timely manner when remote control operations change remote signaling, thus meeting the dual confirmation requirements of the master station's remote control operations and solving the problem of frequent transmission of changing telemetry data and the occupation of a large amount of message space.

[0018] This invention utilizes a BeiDou short message communication management unit to proxy the response to remote control selection and cancellation commands, achieving rapid response during remote control operations. On one hand, this significantly reduces the resource consumption of the main station's communication card; on the other hand, it enables millisecond-level rapid response to remote control confirmation commands, avoiding remote control failures due to response timeouts. Furthermore, this invention employs a retransmission mechanism to ensure that remote control execution commands are traceable, retransmittable, and acknowledgable. Attached Figure Description

[0019] Figure 1 is a schematic diagram of the power distribution automation system.

[0020] Figure 2 is a schematic diagram of the end-to-end communication architecture of the power distribution automation system.

[0021] Figure 3 is a flowchart of the on-site data reporting process in the method of this embodiment of the invention.

[0022] Figure 4 is a flowchart of the main station side command issuance process in the method of this embodiment of the invention.

[0023] Figure 5 illustrates the message processing flow according to an embodiment of the present invention.

[0024] Figure 6 illustrates the remote signaling data transmission process according to an embodiment of the present invention.

[0025] Figure 7 illustrates the telemetry data transmission and processing flow according to an embodiment of the present invention.

[0026] Figure 8 illustrates the remote signaling data protocol conversion and compression processing flow according to an embodiment of the present invention.

[0027] Figure 9 illustrates the business data transmission process according to an embodiment of the present invention.

[0028] Figure 10 illustrates the main station-side data processing and packet loss detection process according to an embodiment of the present invention.

[0029] Figure 11 illustrates the remote control agent process of the BeiDou communication middleware in the BeiDou short message communication management machine according to an embodiment of the present invention.

[0030] Figure 12 illustrates the reliable transmission process of remote control commands according to an embodiment of the present invention. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0032] Before introducing specific embodiments of the present invention, relevant concepts or terms will be explained.

[0033] 1) Distribution Automation System: A distribution automation system is an automated system that monitors and controls the operation of the distribution network. It has functions such as distribution SCADA (supervisory control and data acquisition), feeder automation, and power grid analysis applications. It consists of a distribution automation master station (distribution master station), communication channels, and distribution automation terminals (distribution terminals).

[0034] 2) Distribution Automation Terminal: The distribution automation terminal (distribution terminal) is a key device in the distribution network automation system. It is typically installed at the switching nodes of the distribution lines and is responsible for real-time monitoring of electrical parameters (such as voltage and current) and switch status, as well as executing remote control commands (such as opening and closing) issued by the distribution master station. The distribution automation terminal has functions such as data acquisition, fault detection, communication reporting, and remote control, and is the core device for realizing the "three remotes" (telemetry, remote signaling, and remote control) of the distribution network.

[0035] 3) RDSS (Radio Determination Satellite Service) is one of the distinctive services of the BeiDou Navigation Satellite System, mainly providing short message communication and location reporting functions.

[0036] 4) Beidou Communication Module The Beidou communication module refers to a module that can communicate with the power distribution master station via Beidou RDSS short messages, hereinafter referred to as "Beidou communication module".

[0037] 5) Beidou Short Message Communication Management Unit: The Beidou Short Message Communication Management Unit is a device that can interact with remote communication modules via Beidou satellites. It can preprocess power data and interact with the power distribution master station.

[0038] 6) Beidou Communication Front-end Software: The Beidou communication front-end software is a functional module deployed in the Beidou short message communication management unit, responsible for data interaction with the remote communication module through Beidou satellites.

[0039] 7) Beidou Communication Middleware: Beidou communication middleware is a functional module deployed in the Beidou short message communication management unit to realize communication interaction with the power distribution master station and Beidou front-end software.

[0040] In practice, power distribution terminals in areas without public network coverage often use BeiDou short message service for data transmission. Existing technologies mostly use transparent transmission methods, directly encapsulating and sending distribution automation protocols (such as IEC101 / 104), lacking optimization mechanisms for the characteristics of BeiDou channels.

[0041] According to the BeiDou RDSS (Radio Determination Service) protocol, the minimum interval time (minimum interval between two short message transmissions) for current civilian BeiDou short message communication standard services is 60 seconds. The maximum single transmission capacity of the BeiDou Level 2 communication card used in the power industry is 229 bytes, and the data transmission protocol does not include a receiver status feedback mechanism. Furthermore, distribution automation terminals have certain requirements for latency, bandwidth, and communication reliability in their remote sensing and telemetry communication. When a fault or anomaly occurs in the distribution network, the distribution terminal generates a large amount of remote signaling and telemetry data, which can easily cause channel congestion and communication delays. The minimum time interval requirement of BeiDou short message communication can also easily cause remote control timeouts during remote control selection and calibration execution, leading to remote control failure.

[0042] Existing technologies have addressed the unreliability of BeiDou short message communication by employing a flag bit encoding mechanism. However, there is currently no mature solution for the timeout issue in the remote control selection and return-to-cathode process. For the communication congestion and delays caused by frequent remote signaling and telemetry data transmission, current technology only offers efficient data compression; no other solutions exist. However, multiple experiments have verified that data compression can alleviate communication delays caused by large amounts of remote signaling and telemetry data generated by distribution network faults to some extent (uplink data transmission time is reduced from 4-5 minutes before compression to approximately 2 minutes), but it cannot solve the channel congestion problem caused by frequent signals from distribution terminals.

[0043] To address the aforementioned issues, this invention proposes a power distribution terminal communication optimization method based on BeiDou short message service. Addressing the timeout problem in the remote control selection and return-to-work phase, a remote control operation proxy response mechanism is developed, referencing the BeiDou communication terminal proxy confirmation mechanism used to avoid timeouts in the heartbeat phase of meter data transmission. This mechanism prevents remote control failures due to timeouts. For the communication congestion and delays caused by frequent remote signaling and telemetry data transmission, a frequent remote signaling change shielding reporting mechanism is employed to effectively shield a large amount of useless data transmission, thus avoiding channel congestion and communication delays.

[0044] The method in this embodiment is applied to a power distribution automation system, as shown in Figure 2. The system includes a power distribution automation master station and a BeiDou short message communication management unit interconnected on the master station side, and power distribution automation terminals and BeiDou communication modules interconnected on the field side. The BeiDou short message communication management unit and the BeiDou communication module interact via BeiDou short messages. The data stream starts from the top power distribution master station. Downlink commands are processed by the BeiDou communication middleware and front-end software of the BeiDou short message communication management unit, converted into serial port signals via Ethernet, and then transmitted to the field via satellite by the BeiDou-3 data transmission terminal. The field-side power distribution terminal receives commands and uploads compressed protocol data through the BeiDou communication module, forming a complete two-way communication loop. This enables reliable and efficient transmission of remote control commands, remote signaling data, and telemetry data in an environment without a public network.

[0045] The method in this embodiment includes the following steps: S1) Field-side data reporting process, as shown in Figure 3, includes: the Beidou communication module obtains and parses the response message from the power distribution automation terminal; if it is a remote control message, it sets the highest priority and adds it to the data stream to be sent; if it is a remote signaling message, it blocks the remote signaling messages that change frequently, extracts key information from the remaining remote signaling messages, performs protocol conversion according to the private protocol, and adds it to the data stream to be sent; if it is a telemetry message, it adds it to the data stream to be sent. The telemetry message includes remote signaling data that is periodically collected or remote signaling data triggered by important remote signaling changes; then the data stream to be sent is compressed to generate a Beidou short message and sent. The Beidou short message communication management unit obtains the Beidou short message data stream from the Beidou communication module through a private protocol, restores the data, and reports it to the distribution automation master station; S2) The master station side command issuance process, as shown in Figure 4, includes: the distribution automation master station issues a remote control command, the Beidou short message communication management unit obtains and parses the remote control command, if it is a remote control selection command or a remote control cancellation command, it directly responds to the distribution automation master station with the corresponding message, if it is a remote control execution command, it sends the remote control execution command to the distribution automation terminal through the Beidou communication module and waits for the remote control execution confirmation message, and waits for the timeout to start the retransmission mechanism.

[0046] The above steps systematically improve the integrity and reliability of data transmission by preprocessing the data at the sending end (field side), verifying the integrity of the receiving end (master station side), and designing retransmission for critical services. The details are as follows: As shown in Figure 5, the Beidou communication module receives the message from the power distribution terminal and parses and identifies it. If it is a remote control message, the sending priority is configured to be the highest to ensure the timeliness of remote control reporting.

[0047] In this embodiment, for remote signaling message data, when the distribution automation terminal generates remote signaling data with frequent changes, and there is a risk of channel congestion or the message data volume exceeds the carrying capacity of a single BeiDou short message, a reporting mechanism of "periodicly extracting the latest 10 change remote signals" is adopted. This ensures that key status changes can be reported in a timely manner, while significantly reducing the transmission pressure of the BeiDou channel under extreme conditions, thus balancing data real-time performance and communication reliability. As shown in Figure 6, the remote signaling message data transmission processing includes: Frequent change masking and reporting: When the Beidou communication module detects that a certain remote signaling point generates more than or equal to 10 change information within the general call cycle, it is determined to be a frequent change remote signal, and the reporting of frequent change remote signals is masked. After the general call, the masked frequent remote signals are released to ensure that they can be reported normally after the remote signaling returns to normal. If the frequent remote signals still exist, the first 10 remote signals generated after the release are sent and then masked again. After the general call, the masked frequent remote signals are released. This cycle is repeated to effectively reduce the data transmission frequency, avoid channel congestion, and also periodically send frequent remote signaling data to the power distribution master station.

[0048] Periodic Upload: In the absence of frequent location changes, full remote signaling data collection and upload (i.e., "general call") will still be performed according to the preset period to maintain the integrity and synchronization of the main station data. The threshold for frequent detection and the general call period can be flexibly configured according to actual business needs.

[0049] In this embodiment, for telemetry message data, when the distribution terminal generates telemetry data that needs to be reported, and there is a risk of channel congestion or the data volume exceeds the carrying capacity of a single BeiDou short message, a reporting strategy combining "periodic general call + triggered upload" is adopted. This avoids the BeiDou channel from being blocked by massive amounts of telemetry data while ensuring the real-time performance of data upload and the reliability of system operation. As shown in Figure 7, the remote telemetry message data transmission processing includes: change-triggered reporting: When important telemetry changes such as switch opening and closing are detected, the telemetry data related to the change event is automatically triggered to be uploaded immediately, ensuring that the distribution master station can obtain telemetry information when key state changes occur in a timely manner.

[0050] Periodic Recall Upload: Under normal circumstances without telemetry changes, the system performs full collection and upload of telemetry data (i.e., "recall") according to a preset period to ensure regular data refresh and synchronization. The recall period and waiting time for changed data can be flexibly configured according to actual business needs.

[0051] Therefore, in step S1, when frequently changing remote signaling messages are blocked, and the remaining remote signaling messages are extracted for key information and converted according to a private protocol before being added to the data stream to be sent, the specific steps include: detecting the communication environment and message data volume; if there is a risk of channel congestion or the message data volume exceeds the carrying capacity of a single BeiDou short message, counting the number of remote signaling messages generated by the same remote signaling point; if the number of remote signaling messages generated by the same remote signaling point in a single recall period is less than a specified value (10 in this embodiment), extracting key information from all remote signaling messages, converting according to a private protocol, and adding them to the data stream to be sent; if the number of remote signaling messages generated by the same remote signaling point in a single recall period is greater than a specified value, then in each period, remote signaling messages with a specified number of changes are blocked, and only remote signaling messages with a specified number of changes are recalled. In this embodiment, the specified number of changes is 10, so that remote signaling data that has changed more than 10 times is no longer transmitted in each recall period, and only remote signaling data with less than 10 changes is transmitted, reducing transmission pressure.

[0052] Specifically, after blocking remote signaling messages that have changed a specified number of times at the remote signaling point, the system waits for the general call cycle to arrive. Key information is extracted from the unblocked remote signaling messages, and after protocol conversion according to a private protocol, the messages are added to the data stream to be sent. Then, the blocked remote signaling messages are released. If the number of remote signaling messages that have changed in a single general call cycle is still greater than a specified value, after the next general call cycle arrives, a specified number (10 in this embodiment) of remote signaling messages are selected from the released messages. Specifically, the latest 10 remote signaling messages are selected from the released messages in chronological order. Key information is extracted from the selected messages, and after protocol conversion according to a private protocol, the messages are added to the data stream to be sent. The remaining released remote signaling messages that have changed are blocked, thus achieving the periodic extraction and reporting of the latest 10 changed remote signaling data.

[0053] In this embodiment, when the power distribution terminal detects a change in line status (such as a switch tripping), it needs to report this change information (i.e., "remote signaling data", including SOE sequence events and COS change signals) to the master station. Since the original data format is a standard power communication protocol (such as IEC 101 / 104), the original lengthy and fixed-format status report needs to be simplified into a "brief message" containing only core information to adapt to the limited transmission space of BeiDou short messages. Therefore, it is necessary to compress the remote signaling message data through remote signaling data information extraction and protocol conversion. In step S1, the steps of extracting key information from the remote signaling message and performing protocol conversion according to the private protocol are shown in Figure 8. Specifically, it includes: First step: Extract key information. Identify the remote signaling address, SOE time, and remote signaling status value as key information from each remote signaling data message. In this embodiment, the three most core pieces of information are identified and extracted from the original data message: remote signaling address, precise time of the status change (SOE time), and the new status value at that time. To further save space, secondary information such as COS change signals was proactively discarded in this report and not transmitted.

[0054] Step 2: Repackaging into a compact format. The key information of each remote signaling data packet is arranged sequentially to construct the data body. Starting from the key information corresponding to the second remote signaling data packet in the data body, the SOE time in the key information is updated to a relative time relative to the SOE time of the first remote signaling data packet in the data body. The frame header information and data body length information of the private protocol are added to the data body to obtain the converted complete data frame, thereby obtaining the message after the remote signaling data protocol conversion.

[0055] In this embodiment, the multiple state change records extracted from each remote signaling data message are recombined into a custom, compact data packet. The structure of this data packet is as follows: Frame header (1 byte): A marker, like an envelope, used to identify the beginning of the data packet (e.g., represented by the value 0x68).

[0056] Data body length (1 byte): Explicitly indicates the length of the core content of the data packet.

[0057] Data body: The core content area, composed of multiple status records arranged sequentially. For maximum compression: Device address: uniformly represented by 2 bytes.

[0058] The timestamp uses a smart combination of "absolute time + relative time": the time of the first record includes the complete year, month, day, hour, minute, second, and millisecond, and subsequent records only record the relative second difference with the first record, which greatly reduces the byte usage.

[0059] The status value is represented by only 1 byte.

[0060] The above steps achieve semantic-level efficient compression and improve the effective payload of a single message by reducing and parsing, extracting information, and compactly reconstructing remote signaling data.

[0061] In another specific embodiment, the compressed remote signaling message data may not use the method of protocol semantic parsing and reconstruction, but instead use a general lossless compression algorithm (such as LZ77, Huffman coding, etc.) to compress the original protocol message. Although the compression efficiency may be lower than that of semantic level compression, it can still reduce the amount of data and improve the efficiency of single transmission.

[0062] In this embodiment, for data to be sent whose total length exceeds the maximum carrying capacity of a single BeiDou short message, it is necessary to perform multi-frame compression, numbering, and transmission of the service data, as shown in Figure 9. When compressing the data to be sent to generate BeiDou short messages in step S1, the following steps are included: data framing: if the total length of the data to be sent exceeds the maximum capacity of a single BeiDou short message packet, the data to be sent is divided into blocks according to the maximum capacity of a single BeiDou short message packet (for example, the number of bytes corresponding to the user card level, such as 229 bytes), resulting in multiple data frames F1, F2, ..., Fn. If the total length of the data to be sent does not exceed the maximum capacity of a single BeiDou short message packet, the data to be sent is treated as a single data frame. Frame numbering: a unique sequence number (Seq) is assigned to each data frame, starting from 0 or 1 and used cyclically. The sequence number occupies 2 bytes; Combination and encapsulation: After combining each sequence number with the corresponding data frame, a private protocol header is added to the beginning and a checksum is added to the end to form an encapsulated application layer data packet; Beidou message transmission: The application layer data packet is used as the payload and sent to the Beidou short message communication management unit through the Beidou data transmission terminal, while the transmitted data is cached.

[0063] In step S1 of this embodiment, after the master station receives data from the Beidou communication module, it performs data processing and packet loss checks. When the Beidou short message communication management unit obtains the Beidou short message data stream from the Beidou communication module and performs data restoration, as shown in Figure 10, it includes: 1) Data reception and decompression: Verification and parsing: Verify the received Beidou short message. After the verification is successful, the custom protocol header and data body are parsed out. For example, the data body is parsed out from the message after the remote signaling message data protocol conversion; Data restoration: The Beidou communication front-end software of the Beidou short message communication management unit extracts the remote signaling address, SOE time and remote signaling status value according to the parsed data body, restores the original SOE information, and then generates COS information according to the SOE information, restores the COS information that was not transmitted on site, and reconstructs it into a standard protocol message (such as 101 / 104 protocol) and reports it to the power distribution master station system. Specifically, the remote signaling address, SOE time, and remote signaling status value corresponding to each remote signaling data packet are extracted from the data body. The original SOE information is restored based on the remote signaling address, SOE time, and remote signaling status value. Then, the SOE information is converted into COS information, thereby reconstructing each protocol-converted remote signaling data packet into a standard protocol packet.

[0064] 2) Missing Packet Detection and Re-acquisition: Implementation conditions: Acquire application layer data packets, parse the total number of frames (N) and the corresponding sequence number (Seq) in the protocol header of each application layer data packet; Maintain received data: Query the reception status table of the distribution automation terminal, obtain the expected sequence number and the bitmap of the received frames. In this embodiment, the Beidou communication front-end software maintains a reception status table for each distribution terminal, recording the expected start sequence number and the bitmap of the received frames in the most recent communication; Check for missing packets: Compare the sequence number Seq with the expected sequence number; If the sequence number Seq is equal to the expected sequence number, then accept the data in the corresponding application layer data packet and update the bitmap, while incrementing the expected sequence number by one; If the sequence number Seq is greater than the expected sequence number, then based on the value between the sequence number and the expected sequence number, confirm the sequence number of the missing packet and generate the corresponding re-acquisition request, which is then sent to the Beidou communication module. After receiving the re-acquisition request, the Beidou communication module extracts the corresponding data from the sent cache and resends it to the Beidou short message communication management unit.

[0065] In this embodiment, when confirming the sequence number of a missing packet, data packets with sequence numbers between the expected sequence number and Seq-1 are considered missing packets. Once a missing packet is detected, the master station immediately generates a supplementary data collection request instruction. This instruction includes: instruction type (1 byte, identifying it as a supplementary data collection request), starting missing packet sequence number (2 bytes), and ending missing packet sequence number (2 bytes). It is then sent back to the BeiDou communication terminal on the field side via BeiDou short message service.

[0066] Furthermore, as shown in Figure 10, if the sequence number Seq is less than the expected sequence number, it indicates that the corresponding application layer data packet is a duplicate packet, and the corresponding application layer data packet is deleted.

[0067] In another specific embodiment, during packet loss checking and retransmission, the receiving end does not need to actively maintain a complete reception status table. Instead, when a sequence number discontinuity is detected, it only sends a negative acknowledgment to the sending end, requesting retransmission of the specific lost frame. This method can reduce the overhead of receiving end status maintenance and is suitable for resource-constrained scenarios.

[0068] In step S2 of this embodiment, when the power distribution master station sends a remote control selection or cancellation command to the power distribution terminal, a remote control proxy mechanism is implemented through the BeiDou communication middleware of the BeiDou short message communication management unit. Under this mechanism, for remote control selection in the "local" state, the middleware directly responds with a negative response; for remote control selection in the "remote" state, the middleware directly responds with a positive response, without needing to send the command to the terminal and wait for its return of a negative message. This frees up valuable BeiDou channel resources and communication time for remote control execution, greatly improving the remote control success rate and significantly reducing the probability of remote control timeout. This advantage is particularly prominent in BeiDou communication scenarios with limited channel bandwidth and high latency.

[0069] As shown in Figure 11, in step S2, if it is a remote control selection command or a remote control cancellation command, the corresponding message is directly sent to the distribution automation master station. Specifically, this includes: signal status pre-parsing: if it is a remote control selection command, the corresponding status value is queried from the pre-stored remote signaling table of the distribution automation terminal. In this embodiment, the Beidou communication middleware pre-parses and caches the remote signaling table of the distribution automation terminal, which contains the key "remote / local" signal status. The information in the remote signaling table can be updated with the remote signaling message data content reported by the field side.

[0070] Selection command response logic: When a remote selection command is received from the master station, the middleware immediately queries the current value of the "remote / local" signal; if it is a remote status value (signal value is 1), it directly responds to the distribution automation master station with a remote selection affirmative message; if it is a local status value (signal value is 0), it directly responds to the distribution automation master station with a remote selection negative message.

[0071] Direct response to cancellation command: If it is a remote cancellation command, a remote cancellation confirmation message will be sent directly to the distribution automation master station.

[0072] The above mechanism ensures that the response logic of remote control commands is strictly consistent with the actual local state of the power distribution terminal through real-time synchronization and proxy response of the terminal status via middleware, thereby guaranteeing the safety and reliability of remote control operation.

[0073] In step S2 of this embodiment, to overcome the probability of packet loss in the BeiDou channel, the BeiDou communication middleware of the BeiDou short message communication management unit sends the remote control execution command to the distribution automation terminal via the BeiDou communication module through a retransmission mechanism. By retransmitting if no confirmation is received within the remote control time limit, the success rate of remote control can be effectively improved. As shown in Figure 12, when the remote control execution command is sent to the distribution automation terminal via the BeiDou communication module and the remote control execution confirmation message is awaited, and the retransmission mechanism is initiated after the timeout, the following steps are included: Command encapsulation and transmission: The BeiDou communication middleware encapsulates the remote control execution command into a data frame of a private protocol, specifically into a custom remote control frame, caches the data frame of the current remote control execution command, and then sends the data frame to the distribution automation terminal through the BeiDou communication module.

[0074] Start the retransmission timer: Immediately after the BeiDou communication middleware sends the data frame, it starts the corresponding retransmission timer for the transaction, waiting for the acknowledgment frame returned by the power distribution automation terminal through the BeiDou communication module. The timer timeout T1 is set according to the average delay of BeiDou communication, with a recommended range of 30s to 60s.

[0075] Retransmission Mechanism: If a correct acknowledgment frame is received and the retransmission timer has not expired (i.e., the master station received the correct acknowledgment frame before timer T1 expired), the remote control is considered successful, the retransmission timer is turned off, and the cached data frame of the current remote control execution command is cleared. If a correct acknowledgment frame is not received and the retransmission timer expires (i.e., timer T1 expires without receiving an acknowledgment frame), the master station considers the command or acknowledgment frame lost and will automatically retransmit the original remote control command. Specifically, the cached data frame of the current remote control execution command is sent to the distribution automation terminal via the Beidou communication module. After the data frame is sent, the corresponding retransmission timer is started, and the system waits again for the acknowledgment frame returned by the distribution automation terminal via the Beidou communication module. If the maximum number of retransmissions is reached and a correct acknowledgment frame is still not received, the remote control is considered to have failed, and the cached data frame of the current remote control execution command is cleared. The maximum number of retransmissions, N_max, is configurable, with a recommended range of 1 (which can be configured based on the time the distribution master station waits for the remote control acknowledgment message).

[0076] Furthermore, this invention also proposes a power distribution automation system, which includes a power distribution automation master station and a Beidou short message communication management unit interconnected on the master station side, and a power distribution automation terminal and a Beidou communication module interconnected on the field side. The Beidou short message communication management unit and the Beidou communication module interact through Beidou short messages. The power distribution automation system is programmed or configured to execute the steps of the power distribution terminal communication optimization method based on Beidou short messages described in this embodiment.

[0077] In summary, this invention discloses a method for optimizing communication in distribution terminals based on BeiDou short messages. This method is applied to distribution automation systems and establishes a reliable end-to-end communication mechanism at the application layer, compensating for the transmission defects of BeiDou short messages in distribution automation services. The compact format design significantly improves transmission efficiency; the missing packet detection and re-acquisition mechanism ensures data integrity; and the remote retransmission mechanism improves the success rate of critical services. This invention has the following technical innovations: 1) Remote signaling data information extraction and protocol conversion. To solve the problem of low transmission efficiency caused by protocol message redundancy, this invention achieves semantic-level efficient compression by performing protocol parsing, information extraction, and compact reconstruction of remote signaling data, thereby increasing the effective payload of a single message. To avoid the problem of BeiDou transmission channel congestion caused by frequent signal interruptions due to secondary node jitter in distribution terminals, this invention adopts a frequent remote signaling change shielding reporting mechanism, effectively shielding a large amount of useless data transmission and avoiding channel congestion and communication delays.

[0078] 2) Telemetry data "periodic recall + triggered upload". To address the problem of frequent transmission of changing telemetry data and its large consumption of message space, this invention adopts a mechanism combining "periodic recall + triggered upload". This ensures that telemetry data is refreshed regularly without occupying too much data space, and also ensures that when remote control operations change the remote signal, the refreshed telemetry data can be uploaded in a timely manner, meeting the dual confirmation requirements of the master station's remote control operations.

[0079] 3) Remote control operation "proxy response + command retransmission". To solve the problem of remote control timeout failure due to long remote control operation time, this invention adopts the Beidou communication management unit to proxy the remote control selection command, realizing rapid response during remote control operation: on the one hand, it greatly reduces the resource consumption of the main station communication card, and on the other hand, it realizes the millisecond-level rapid response of the remote control confirmation command, avoiding remote control failure due to response timeout; to solve the problem that remote control commands may be lost in unreliable channels, this invention assigns a transaction identifier to the remote control command and sets a limited retransmission mechanism to ensure that the command is traceable, retransmittable, and acknowledgable.

[0080] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and / or one or more blocks of the block diagrams. These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowcharts and / or one or more block diagrams. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and / or one or more block diagrams.

[0081] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for optimizing power distribution terminal communication based on BeiDou short message service, characterized in that, The method is applied to a distribution automation system, which includes a distribution automation master station and a Beidou short message communication management unit interconnected on the master station side, and distribution automation terminals and Beidou communication modules interconnected on the field side. The Beidou short message communication management unit and the Beidou communication module interact via Beidou short messages. The method includes the following steps: the Beidou communication module obtains and parses the response messages from the distribution automation terminals. If it is a remote control message, it sets the highest priority and adds it to the data stream to be sent. If it is a remote signaling message, it blocks frequently changing remote signaling messages, extracts key information from the remaining remote signaling messages, performs protocol conversion according to a private protocol, and adds it to the data stream to be sent. If it is a telemetry message, it adds it to the data stream to be sent. The telemetry message includes periodically collected telemetry data or telemetry data triggered by important telemetry changes; then the data stream to be sent is compressed to generate a BeiDou short message and sent to the BeiDou short message communication management unit; the BeiDou short message communication management unit obtains the BeiDou short message data stream from the BeiDou communication module, restores the data, and reports it to the distribution automation master station; the distribution automation master station issues a remote control command, the BeiDou short message communication management unit obtains and parses the remote control command, if it is a remote control selection command or a remote control cancellation command, it directly responds to the distribution automation master station with the corresponding message, if it is a remote control execution command, it sends the remote control execution command to the distribution automation terminal through the BeiDou communication module and waits for the remote control execution confirmation message, and waits for the timeout to start the retransmission mechanism.

2. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 1, characterized in that, When extracting key information from remote signaling messages and performing protocol conversion according to a private protocol, the specific steps include: identifying the remote signaling address, SOE time, and remote signaling status value as key information from each remote signaling data message; sequentially arranging the key information of each remote signaling data message to construct a data body; starting from the key information corresponding to the second remote signaling data message in the data body, updating the SOE time in the key information to a relative time relative to the SOE time of the first remote signaling data message in the data body; adding frame header information and data body length information of the private protocol to the data body to obtain the converted data frame.

3. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 2, characterized in that, When the BeiDou short message communication management unit acquires the BeiDou short message data stream from the BeiDou communication module and performs data restoration, it includes the steps of data reception and decompression. Specifically, it includes: parsing the data body from the message after remote signaling data protocol conversion; extracting the remote signaling address, SOE time, and remote signaling status value corresponding to each remote signaling data message from the data body; restoring the original SOE information based on the remote signaling address, SOE time, and remote signaling status value; and then converting the SOE information to generate COS information, thereby reconstructing each protocol-converted remote signaling data message into a standard protocol message.

4. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 1, characterized in that, When filtering frequently changing remote signaling messages and adding the remaining messages to the data stream after extracting key information and converting them according to a private protocol, the process includes: detecting the communication environment and message data volume; if there is a risk of channel congestion or the message data volume exceeds the carrying capacity of a single BeiDou short message, counting the number of remote signaling messages generated by the same remote signaling point; if the number of remote signaling messages generated by the same remote signaling point in a single call cycle is less than a specified value, extracting key information from all remote signaling messages and converting them according to a private protocol before adding them to the data stream; if the number of remote signaling messages generated by the same remote signaling point in a single call cycle is less than a specified value, then adding the remaining messages to the data stream after extracting key information and converting them according to a private protocol. If the number exceeds a specified value, then remote communication messages after the specified number of changes of the remote communication point are blocked. The system waits for the general call cycle to arrive, extracts key information from the unblocked remote communication messages, performs protocol conversion according to the private protocol, adds them to the data stream to be sent, and then releases the blocked remote communication messages. If the number of remote communication messages generated by the remote communication point in a single general call cycle still exceeds a specified value, after the next general call cycle arrives, a specified number of remote communication messages are selected from the released remote communication messages. The key information of the selected remote communication messages is extracted, performs protocol conversion according to the private protocol, adds them to the data stream to be sent, and the remaining released remote communication messages are blocked.

5. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 4, characterized in that, When selecting a specified number of remote communication messages from the released remote communication messages, the specific selection is made according to the chronological order of the released messages.

6. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 1, characterized in that, When compressing the data stream to be sent to generate BeiDou short messages, the process includes: if the total length of the data to be sent exceeds the maximum capacity of a single BeiDou short message packet, the data to be sent is divided into blocks according to the maximum capacity of a single BeiDou short message packet to obtain multiple data frames; if the total length of the data to be sent does not exceed the maximum capacity of a single BeiDou short message packet, the data to be sent is treated as a single data frame; a unique sequence number is assigned to each data frame, and each sequence number is combined with the corresponding data frame, a protocol header of a private protocol is added to its header, and a checksum is added to its tail to form an encapsulated application layer data packet; the application layer data packet is sent to the BeiDou short message communication management unit, and the sent data is buffered simultaneously.

7. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 6, characterized in that, When the BeiDou short message communication management unit acquires the BeiDou short message data stream from the BeiDou communication module and restores the data, it also includes steps of missing packet checking and supplementary acquisition. Specifically, this includes: acquiring application layer data packets, parsing the total number of frames and the corresponding sequence number in the protocol header of each application layer data packet; querying the receiving status table of the distribution automation terminal to obtain the expected sequence number and the bitmap of the received frames; comparing the sequence number with the expected sequence number; if the sequence number is equal to the expected sequence number, then accepting the data in the corresponding application layer data packet and updating the bitmap, while incrementing the expected sequence number by one; if the sequence number is greater than the expected sequence number, then confirming the sequence number of the missing packet based on the value between the sequence number and the expected sequence number, generating a corresponding supplementary acquisition request and sending it to the BeiDou communication module. After receiving the supplementary acquisition request, the BeiDou communication module extracts the corresponding data from the sent buffer and resends it to the BeiDou short message communication management unit.

8. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 1, characterized in that, If the command is a remote control selection command or a remote control cancellation command, the corresponding message will be sent directly to the distribution automation master station. Specifically, if it is a remote control selection command, the corresponding status value will be queried from the pre-stored remote signaling table of the distribution automation terminal. If it is a remote status value, a remote control selection affirmative message will be sent directly to the distribution automation master station. If it is a local status value, a remote control selection negative message will be sent directly to the distribution automation master station. If it is a remote control cancellation command, a remote control cancellation confirmation message will be sent directly to the distribution automation master station.

9. The power distribution terminal communication optimization method based on BeiDou short message service according to claim 1, characterized in that, When a remote control execution command is sent to a distribution automation terminal via the BeiDou communication module and a remote control execution confirmation message is awaited, and a retransmission mechanism is initiated after a timeout, the following steps are included: The remote control execution command is encapsulated into a data frame of a private protocol, the current remote control execution command data frame is cached, and then the data frame is sent to the distribution automation terminal via the BeiDou communication module. After the data frame is sent, a corresponding retransmission timer is started, waiting for a confirmation frame returned by the distribution automation terminal via the BeiDou communication module. If a correct confirmation frame is received and the retransmission timer has not timed out, the remote control is considered successful, the retransmission timer is closed, and the cached data frame of the current remote control execution command is cleared. If a correct confirmation frame is not received and the retransmission timer times out, the cached data frame of the current remote control execution command is sent to the distribution automation terminal via the BeiDou communication module. After the data frame is sent, a corresponding retransmission timer is started, and the system again waits for a confirmation frame returned by the distribution automation terminal via the BeiDou communication module. If the maximum number of retransmissions is reached and a correct confirmation frame is still not received, the remote control is considered to have failed, and the cached data frame of the current remote control execution command is cleared.

10. A power distribution automation system, characterized in that, The power distribution automation system includes a power distribution automation master station and a Beidou short message communication management unit interconnected on the master station side, and a power distribution automation terminal and a Beidou communication module interconnected on the field side. The Beidou short message communication management unit and the Beidou communication module interact through Beidou short messages. The power distribution automation system is programmed or configured to execute the steps of the power distribution terminal communication optimization method based on Beidou short messages as described in any one of claims 1 to 9.

Images