Wind power plant long-distance communication method and system based on wireless ad hoc network

Abstract

The invention relates to the technical field of wind power Internet of Things communication, in particular to a wind power plant long-distance communication method and system based on a wireless ad hoc network, and the method comprises the steps: deploying a relay module with a wind driven generator as a node, and carrying out the self-adaptive networking based on geographic coordinates and signal intensity; electing a cluster head node to establish a tree-mesh hybrid topology; the source node sends a routing request, establishes a data transmission path, monitors performance and triggers retransmission; data are transmitted in a hierarchical manner, and low time delay of real-time data and high throughput of daily use are guaranteed; and preprocessing the cluster head, compressing the data, adding a security label and then forwarding. According to the method, signal interruption caused by blade shielding is solved, key instruction time delay is reduced through hierarchical routing and composite index evaluation, log transmission efficiency is improved through the multi-path fountain code technology, the service blocking problem is eradicated, energy consumption is reduced through the dormancy scheduling and compression algorithm, data safety is enhanced, the network lifetime is prolonged, and the total ownership cost of a communication system is reduced.

Description

Technical Field

[0001] This invention relates to the field of wind power Internet of Things (IoT) communication technology, specifically to a long-distance communication method and system for wind farms based on a wireless ad hoc network. Background Technology

[0002] Traditional wind farm communication relies on fiber optics or point-to-point microwave, which is costly and inflexible in complex terrain. Existing wireless ad hoc network solutions face dual challenges from the physical environment and system resources. At the physical level, the periodic rotation of wind turbine blades (3-6 seconds) causes regular obstruction of wireless signals, resulting in a link interruption rate of over 40%. Existing protocol-level retransmission mechanisms are unable to cope with millisecond-level signal fading. The strip-shaped distribution of wind farms (typically 10km in length) forces end nodes to go through 8-12 relays, and traditional routing protocols accumulate latency of over 500ms, which cannot meet the 100ms real-time requirement of SCADA data. At the same time, the conflict between control commands (<1% of traffic) and batch logs (>70% of traffic) causes the failure rate of shutdown command delivery to reach 15%.

[0003] At the system resource level, the high temperature and vibration environment inside the nacelle limits the hardware capabilities of the nodes. Existing equipment only supports basic RSSI measurements and cannot perform data compression / anomaly detection locally, resulting in invalid data accounting for more than 30% and exacerbating congestion. The continuous monitoring mode causes the nodes to consume up to 120kWh of power per year, and battery-powered nodes need to be replaced frequently. The weak security architecture makes lightweight passwords vulnerable to replay attacks, and the injection of false data has caused wind turbine disconnection accidents.

[0004] Therefore, existing wireless ad hoc networks in wind farms suffer from insufficient environmental adaptability, weak resource utilization, and poor security. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide a long-distance communication method and system for wind farms based on wireless ad hoc networks, so as to solve the problems of insufficient environmental adaptability, weak resource utilization and security of existing wireless ad hoc networks for wind farms.

[0006] According to a first aspect of the present invention, a long-distance communication method for wind farms based on a wireless ad hoc network is provided, comprising:

[0007] In the wind farm, a multi-hop relay wireless communication module is deployed with each wind turbine as a node; the relay wireless communication module executes an adaptive networking protocol based on geographical coordinates and real-time signal strength. After the node starts up, it broadcasts a beacon frame containing location, device ID and communication capabilities. After receiving the beacon frame, neighboring nodes build a neighbor table and calculate the link quality index.

[0008] Obtain all neighbor tables and link quality indices, and dynamically elect a cluster head node by combining the link quality index and geographical location information through a distributed election algorithm. The cluster head node is used to coordinate intra-cluster communication and cross-cluster routing scheduling, and establish a tree-mesh hybrid topology with the booster station central server as the root node.

[0009] The source node sends a routing request packet to the root node. Intermediate nodes calculate the reliability index of the path based on the link quality prediction model. If the reliability index meets the standard, the routing request packet is forwarded. A hierarchical routing protocol is used to establish a data transmission path. After receiving the first valid routing request packet, the booster station central server returns a routing response along the reverse path, establishes a data transmission path, and evaluates the transmission performance of the path. When a delay > 100ms or a packet loss rate > 10% is detected, route retransmission is automatically triggered.

[0010] The system retrieves the data content of the routing request packet and enables direct transmission of the real-time monitoring data of the wind farm using the UDP protocol. For batch fault logs, it adopts the fragmented TCP protocol combined with fountain code encoding, utilizes multiple data transmission paths for parallel transmission, and adjusts the data fragment size and retransmission number according to the network congestion status.

[0011] The cluster head node performs multi-level data preprocessing to eliminate redundant information, runs an improved LZW-Hybrid compression algorithm to losslessly compress the data sent by other nodes in the cluster to obtain data packets, adds a timestamp and a SHA-256 hash value label based on the source node ID to each data packet, generates verifiable data units, and forwards them to the booster station. The booster station then sends information to complete long-distance communication of the wind farm.

[0012] Preferably, a multi-hop relay wireless communication module is deployed within the wind farm, with each wind turbine as a node, including:

[0013] A multi-hop relay wireless communication module is deployed on the top of each wind turbine nacelle;

[0014] After the relay wireless communication module starts up, it performs a hardware self-test process, including:

[0015] Perform a location verification to confirm the validity of GPS / BeiDou coordinates. If the location is out of tolerance, trigger a level 1 alarm.

[0016] Perform RF diagnostics to measure the antenna VSWR. If the antenna VSWR is >1.8 or the receiver sensitivity is <

[0017] -110dBm, triggering a level 2 alarm;

[0018] Real-time monitoring of the ambient temperature surrounding the relay wireless communication module.

[0019] Preferably, when electing the cluster head node, the following is also included:

[0020] A genetic algorithm is used to dynamically adjust the election weight of the cluster head node. The weight factors for the election weight of the cluster head node include: the node's remaining power, historical link stability, and the number of hops with the booster station.

[0021] The weights are recalculated every 6 hours, and the election of cluster head nodes is re-executed based on the calculated weights.

[0022] When a new node is added, the topology information is updated through restricted flooding broadcast, and the flooding radius is set to 3 hops according to the wind farm density;

[0023] When topology splits, an emergency networking mode is activated, forming a temporary relay group composed of the three nearest nodes, and Turbo coding is used to enhance the decoding capability of weak signals.

[0024] Preferably, when forwarding the routing request packet, the intermediate node further includes:

[0025] Intermediate nodes calculate the forwarding probability using the following formula, and forward the routing request packet according to the forwarding probability;

[0026] P = min(1, LQI / 85)

[0027] Where P is the forwarding probability and LQI is the link quality index;

[0028] When evaluating the transmission performance of a path, the following should be included:

[0029] The composite index is calculated using the following formula. If the composite index CI ≤ 0.7, the data transmission path is unqualified, and route retransmission is triggered.

[0030] CI=0.6×PRR+0.3×(1-Delay / Dmax)+0.1×ETX

[0031] Where PRR is the packet reception rate, Dmax is the maximum allowed delay, Delay is the transmission delay of the current path, and ETX is the expected number of transmissions.

[0032] Preferably, during data transmission, the following are included:

[0033] Define a three-level routing priority: emergency stop commands are the highest priority, SCADA data is the medium priority, and log files are the lowest priority. When the highest priority data transmission is executed, the low priority data transmission is interrupted.

[0034] Preferably, batch fault logs are transmitted using a fragmented TCP protocol combined with fountain code encoding, utilizing multiple data transmission paths in parallel, including:

[0035] The batch fault log data is fragmented, and the fragment size is dynamically adjusted within the range of 128B to 1KB based on the real-time network throughput.

[0036] RaptorQ fountain codes are used to encode fragments, generating a set of encoded symbols, with the proportion of redundant symbols set to 15% to 35%. During multipath transmission, the encoded symbols are allocated to three independent paths for parallel transmission.

[0037] The receiver decodes the original data based on the received k+1 symbols, where k is the original number of fragments. When decoding fails, only the missing symbol index is retransmitted, and the upper limit of the number of retransmissions is set according to the channel signal-to-noise ratio.

[0038] Preferably, the cluster head node performs multi-level data preprocessing to eliminate redundant information and runs an improved LZW-Hybrid compression algorithm to perform lossless compression of data packets, including:

[0039] The cluster head node establishes a dynamic dictionary window to perform LZW encoding on the input data stream;

[0040] Perform Huffman compression on the LZW encoded data;

[0041] To address the spatiotemporal correlation of SCADA data, differential coding preprocessing is added: for sensor data with a change of <1% within 5 consecutive frames, only the full value of the first frame and the difference between subsequent frames are stored;

[0042] After compression, a compression metadata header is added, which includes the original length, compression version, and checksum.

[0043] Preferably, each data packet is labeled with a timestamp and a SHA-256 hash value based on the source node ID to generate a verifiable data unit before being forwarded to the booster station, including:

[0044] When the cluster head node generates a data packet, it uses a hardware true random number generator to obtain the current millisecond-level timestamp T, concatenates the source node ID with the timestamp T, and calculates the SHA-256 hash value H1. The data packet structure includes: a 2-byte packet header identifier, a 4-byte T, a 32-byte H1, and a variable-length compressed data body.

[0045] After receiving the data, the booster station performs a four-step verification:

[0046] Determine if the time stamp T deviates from the system time by ≤5s; SHA-256 hash value H2 is obtained by concatenating the source node identifier ID with the timestamp T; compare whether hash value H1 and hash value H2 are consistent; verify the CRC32 code of the compressed data body.

[0047] If any step fails, the data packet is discarded and a security event log is generated.

[0048] According to a second aspect of the present invention, a long-distance communication system for wind farms based on a wireless ad hoc network is provided, for performing the method described in any one of the above embodiments, comprising:

[0049] The node deployment module is installed on the top of each wind turbine nacelle. It integrates a dual-frequency wireless communication unit, a high-precision positioning unit, and an environmental monitoring sensor to perform hardware self-tests. If the self-test fails, it triggers an audible and visual alarm and blocks network access.

[0050] The topology management module runs a distributed election protocol and optimization algorithm to dynamically elect cluster head nodes based on the neighbor table and link quality index. It calculates the election weight by combining three indicators: the percentage of remaining power of the node, the number of effective neighbors, and the minimum number of hops to the booster station. It generates a hybrid topology of tree backbone and mesh redundant links and forces vertically adjacent wind turbines within a 500-meter distance to establish direct connection channels.

[0051] The routing management module has a built-in business hierarchy engine and path evaluator, which is used to calculate reliability indicators when processing routing request packets. If the reliability indicators meet the standards, the routing request packet is forwarded and a path is reserved for the highest priority service to preempt the channel.

[0052] The data transmission module, which includes a fountain code encoder and a multi-path scheduler, is used to encode batch log data in segments and add dynamic redundancy, and to transmit the data in parallel using multiple data transmission paths.

[0053] The edge processing module, deployed on the cluster head node, integrates a data compression engine and a security tag generation unit. It is used to perform spatiotemporal differential encoding, dictionary compression, and entropy encoding secondary compression, and adds millisecond-level timestamps and source node binding hash tags to data packets.

[0054] Preferably, the edge processing module includes:

[0055] The security verification unit, located on the booster station server, is equipped with a true random number generator and a password processor to perform four-step verification:

[0056] The deviation between the timestamp of the verification data packet and the system clock should not exceed 5 seconds.

[0057] Recalculate the SHA-256 hash value of the source node identifier concatenated with the timestamp;

[0058] Compare whether hash values ​​H1 and H2 are the same;

[0059] Verify the CRC32 code of the compressed data body;

[0060] The blockchain evidence storage unit is used to build a hash tree for the data after the four-step verification is passed, according to the 10-minute time intervals. The root of the tree is written into the distributed ledger through the consensus mechanism, providing an integrity verification interface.

[0061] The exception handling unit is used to discard data packets that fail the four-step verification and generate encrypted audit logs, recording the fault type, source node, and occurrence time.

[0062] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0063] It is understood that the technical solution presented in this invention deploys relay modules using wind turbines as nodes, and adaptively networks based on geographical coordinates and signal strength; elects cluster head nodes to establish a tree-mesh hybrid topology; source nodes send routing requests, establish data transmission paths, monitor performance, and trigger retransmissions; data is transmitted in a hierarchical manner to ensure low latency for real-time data and high throughput for logs; the cluster head preprocesses and compresses data and adds security tags before forwarding. This invention solves the signal interruption caused by blade occlusion, reduces the latency of critical commands through hierarchical routing and composite index evaluation, improves log transmission efficiency through multi-path fountain code technology, eliminates service blocking problems, reduces energy consumption through sleep scheduling and compression algorithms, enhances data security, extends network lifetime, and reduces the total cost of ownership of the communication system.

[0064] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0065] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0066] Figure 1 This is a schematic diagram illustrating the steps of a long-distance communication method for wind farms based on a wireless ad hoc network, according to an exemplary embodiment.

[0067] Figure 2 This is a schematic flowchart illustrating the process of establishing a tree-mesh hybrid topology according to an exemplary embodiment;

[0068] Figure 3 This is a schematic block diagram illustrating a long-distance communication system for a wind farm based on a wireless ad hoc network, according to an exemplary embodiment.

[0069] Figure 4 This is a schematic block diagram illustrating the structure of an edge processing module according to an exemplary embodiment. Detailed Implementation

[0070] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0071] In one embodiment, Figure 1 This is a schematic diagram illustrating the steps of a long-distance communication method for wind farms based on a wireless ad hoc network, according to an exemplary embodiment. See also... Figure 1 and Figure 2 This paper provides a long-distance communication method for wind farms based on wireless ad hoc networks, including:

[0072] Step S11: Deploy a multi-hop relay wireless communication module in the wind farm with each wind turbine as a node; the relay wireless communication module executes an adaptive networking protocol based on geographical coordinates and real-time signal strength. After the node starts, it broadcasts a beacon frame containing location, device ID and communication capabilities. After receiving the beacon frame, neighboring nodes build a neighbor table and calculate the link quality index.

[0073] In practice, this step uses each wind turbine in the wind farm as a network node. Each node is equipped with a multi-hop relay wireless communication module, enabling it to relay and support long-distance multi-hop communication. The relay wireless communication module executes an adaptive networking protocol based on the geographical coordinates (such as latitude and longitude) and real-time signal strength of each node. It can dynamically adjust the networking method according to the environment, adapting to the complex terrain and signal changes of the wind farm. After a node starts up, it actively broadcasts a "beacon frame," which contains key information about the node, including its location (geographic coordinates), unique device identifier (device ID), and communication capabilities (such as transmission rate and coverage area), used to inform surrounding nodes of its existence and basic attributes.

[0074] Upon receiving a beacon frame, a neighboring node will construct a neighbor table based on this information. The neighbor table records basic information about reachable nodes in the vicinity and calculates the Link Quality Index (LQI) to measure the quality of the communication link with the neighboring node, providing a basis for subsequent routing and cluster head election.

[0075] It should be noted that multi-hop relay wireless communication modules are deployed within the wind farm, with each wind turbine serving as a node. These modules include:

[0076] A multi-hop relay wireless communication module is deployed on the top of each wind turbine nacelle. This location helps reduce signal obstruction and improves wireless communication quality.

[0077] After the relay wireless communication module starts up, it performs a hardware self-test process, including: performing a positioning verification to verify the validity of GPS / BeiDou coordinates. If the positioning is out of tolerance, a level one alarm is triggered to ensure the accuracy of node location information and provide a reliable basis for network formation and routing selection.

[0078] Perform RF diagnostics to measure the antenna VSWR. If the antenna VSWR is >1.8 (indicating poor antenna matching) or the receiver sensitivity is <-110dBm (indicating insufficient receiver capability), a level 2 alarm will be triggered.

[0079] Real-time monitoring of the ambient temperature around the relay wireless communication module is crucial because the high temperature and vibration environment inside the cabin may affect the module's operation. This inspection is used to promptly grasp the temperature status and prevent hardware failures caused by high temperatures.

[0080] Step S12: Obtain all neighbor tables and link quality indices. Dynamically elect a cluster head node by combining the link quality index and geographical location information through a distributed election algorithm. The cluster head node is used to coordinate intra-cluster communication and cross-cluster routing scheduling, and establish a tree-mesh hybrid topology with the booster station central server as the root node.

[0081] In practice, a neighbor table (recording information about neighboring nodes) and a calculated Link Quality Index (LQI) (measuring the quality of communication links between nodes) provide the foundational data for subsequent cluster head election. A distributed election algorithm dynamically selects the cluster head node by combining the LQI and geographic location information (reflecting the spatial distribution of nodes). Distributed election means that no centralized control is required; it is completed collaboratively among nodes, and its dynamism ensures adaptability to changes in network conditions. The cluster head node, as the core of the cluster, is responsible for coordinating communication among nodes within the cluster (such as data aggregation and forwarding) and scheduling routes between different clusters (cross-cluster data transmission path planning), playing a crucial role in regional coordination and relay. Ultimately, a "tree-mesh hybrid topology" is formed with the booster station's central server as the root node. The tree structure ensures a clear backbone transmission path for data to the root node (booster station), while the mesh structure provides redundant links, enhancing the stability and fault tolerance of long-distance multi-hop communication and ensuring the reliability of global communication across the wind farm.

[0082] It should be noted that the election of the cluster head node also includes:

[0083] A genetic algorithm is used to dynamically adjust the election weight of the cluster head node. The weighting factors of the election weight of the cluster head node include: the node's remaining power, historical link stability, and the number of hops with the booster station.

[0084] The weights are recalculated every 6 hours to avoid overloading a single node, and the election of the cluster head node is re-executed based on the calculated weights.

[0085] When a new node joins, the topology information is updated through restricted flooding broadcast. The flooding radius is set to 3 hops based on the wind farm density. This ensures that new nodes can quickly integrate into the network while avoiding network congestion caused by unrestricted broadcasting.

[0086] When topology splits, an emergency networking mode is activated, forming a temporary relay group composed of the three nearest nodes, and Turbo coding is used to enhance the decoding capability of weak signals.

[0087] Step S13: The source node sends a routing request packet to the root node. The intermediate node calculates the reliability index of the path based on the link quality prediction model. If the reliability index meets the standard, the routing request packet is forwarded. A hierarchical routing protocol is used to establish a data transmission path. After receiving the first valid routing request packet, the booster station central server returns a routing response along the reverse path to establish a data transmission path and evaluates the transmission performance of the path. When a delay > 100ms or a packet loss rate > 10% is detected, route retransmission is automatically triggered.

[0088] In practice, the wind turbine node acts as the source node, sending a Route Request Message (RREQ) packet to the booster station's central server to request the establishment of a valid data transmission path from the source node to the booster station. Upon receiving the RREQ, intermediate nodes calculate the path's reliability metrics (such as packet reception rate and latency) based on a link quality prediction model, and only forward the RREQ if the reliability meets the criteria. This mechanism filters out higher-quality paths, avoiding ineffective forwarding that wastes network resources.

[0089] A hierarchical routing protocol (i.e., allocating path resources according to service priority) is adopted to establish data transmission paths, ensuring that high-level services such as emergency instructions can obtain transmission resources first.

[0090] After receiving the first valid RREQ (Reverse Routing Equation), the booster station's central server will return a routing response along the reverse transmission path of that RREQ, confirming the data transmission path and establishing a bidirectional communication link between the source node and the booster station. Simultaneously, a path maintenance mechanism is initiated to monitor transmission performance (such as latency and packet loss rate) in real time. When latency > 100ms or packet loss rate > 10%, route retransmission is automatically triggered to promptly repair unstable paths and ensure the continuity and reliability of data transmission.

[0091] It should be noted that when the intermediate node forwards the routing request packet, it also includes:

[0092] Intermediate nodes calculate the forwarding probability using the following formula, and forward the routing request packet according to the forwarding probability;

[0093] P = min(1, LQI / 85)

[0094] Where P is the forwarding probability and LQI is the link quality index; it can effectively suppress broadcast storms.

[0095] When evaluating the transmission performance of a path, the following should be included:

[0096] The composite index is calculated using the following formula. If the composite index CI ≤ 0.7, the data transmission path is unqualified, and route retransmission is triggered.

[0097] CI=0.6×PRR+0.3×(1-Delay / Dmax)+0.1×ETX

[0098] Where PRR is the packet reception rate, Dmax is the maximum allowed delay, Delay is the transmission delay of the current path, and ETX is the expected number of transmissions.

[0099] Step S14: Obtain the data content of the routing request packet, enable direct transmission of the real-time monitoring data of the wind farm using the UDP protocol to ensure low-latency delivery within 100ms; for batch fault logs, use the fragmented TCP protocol combined with fountain code encoding, utilize multiple data transmission paths for parallel transmission to improve throughput, and adjust the data fragment size and retransmission number according to the network congestion status.

[0100] It should be noted that data transmission includes:

[0101] Define a three-level routing priority: emergency stop commands are the highest priority, SCADA data is the medium priority, and log files are the lowest priority. When the highest priority data transmission is executed, the low priority data transmission is interrupted.

[0102] In practice, the first step is to acquire the data content carried by the RREQ packet and clarify the data type (such as real-time monitoring data, batch fault logs, etc.) to provide a basis for subsequent differentiated transmission. For real-time monitoring data (such as equipment status data that requires real-time feedback), high-priority UDP protocol is used for direct transmission. UDP is characterized by low latency; by assigning it high priority, it ensures that this type of data can be delivered within 100ms, meeting the real-time requirements of wind farms (such as real-time monitoring and control of SCADA data).

[0103] For batch fault logs (data with large volume, low real-time requirements but needing to be transmitted in its entirety), a fragmented TCP protocol combined with fountain code encoding is used: fragmentation can break large data volumes into small segments, making them easier to transmit; fountain code encoding improves the data's ability to resist packet loss during transmission by generating redundant symbols; and multi-path parallel transmission utilizes multiple independent paths to send data simultaneously, significantly improving the overall throughput.

[0104] Meanwhile, the system will sense network congestion in real time and dynamically adjust the size of data fragments (to avoid large fragments exacerbating congestion) and the number of retransmissions (to ensure data integrity) according to the degree of congestion, thereby optimizing transmission efficiency and adapting to the complex and ever-changing network environment of wind farms.

[0105] It should be noted that the batch fault logs are processed using a fragmented TCP protocol combined with fountain code encoding, and are transmitted in parallel via multiple data transmission paths, including:

[0106] The batch fault log data is fragmented, and the fragment size is dynamically adjusted within the range of 128B to 1KB based on the real-time network throughput.

[0107] RaptorQ fountain codes are used to encode fragments, generating a set of encoded symbols. The proportion of redundant symbols is set to 15% to 35%. During multipath transmission, the encoded symbols are allocated to three independent paths for parallel transmission. The path selection criteria are: latency difference ≤ 20ms and packet loss rate difference ≤ 5%.

[0108] The receiver decodes the original data based on the received k+1 symbols, where k is the original number of fragments. When decoding fails, only the missing symbol index is retransmitted, and the upper limit of the number of retransmissions is set according to the channel signal-to-noise ratio.

[0109] In practice, the receiver can decode the original data after receiving k+1 symbols.

[0110] Step S15: The cluster head node performs multi-level data preprocessing to eliminate redundant information, runs the improved LZW-Hybrid compression algorithm to losslessly compress the data sent by other nodes in the cluster to obtain data packets, adds a timestamp and a SHA-256 hash value label based on the source node ID to each data packet, generates verifiable data units, and forwards them to the booster station. Then, the booster station sends information to complete the long-distance communication of the wind farm.

[0111] In practice, the cluster head node first performs multi-level preprocessing on the received raw data. The core of this preprocessing is to eliminate redundant information (such as filtering invalid monitoring data and merging duplicate content), reducing the proportion of invalid data and lightening the load for subsequent transmissions. Then, an improved LZW-Hybrid compression algorithm is run to perform lossless compression, generating data packets. This algorithm combines LZW coding, Huffman double compression, and differential coding preprocessing for SCADA data, ultimately achieving an average compression ratio of 8:1. This process significantly reduces the size of data packets, improves wireless bandwidth utilization, and ensures that the compressed data can be fully recovered.

[0112] Two key tags are added to each compressed data packet: one is a millisecond-level timestamp to ensure data timeliness; the other is a SHA-256 hash value based on the source node ID, used to verify data integrity and source legitimacy (the booster station will subsequently verify whether the data has been tampered with by recalculating the hash value).

[0113] After preprocessing, compression, and security marking, the data forms verifiable data units, which are forwarded by the cluster head node to the booster station; finally, the information is sent uniformly through the booster station to complete the long-distance communication of the wind farm.

[0114] It should be noted that the cluster head node performs multi-level data preprocessing to eliminate redundant information and runs an improved LZW-Hybrid compression algorithm to perform lossless compression of data packets. This includes: the cluster head node establishing a dynamic dictionary window and performing LZW encoding on the input data stream; performing Huffman secondary compression on the LZW-encoded data; adding differential coding preprocessing to address the spatiotemporal correlation of SCADA data: for sensor data with a change of <1% within 5 consecutive frames, only the full value of the first frame and the difference between subsequent frames are stored; and adding a compressed metadata header after compression, which includes the original length, compression version, and checksum.

[0115] It should be noted that after adding a timestamp and a SHA-256 hash value label based on the source node ID to each data packet to generate a verifiable data unit, it is forwarded to the booster station, including:

[0116] When the cluster head node generates a data packet, it uses a hardware true random number generator to obtain the current millisecond-level timestamp T, concatenates the source node ID with the timestamp T, and calculates the SHA-256 hash value H1. The data packet structure includes: a 2-byte packet header identifier, a 4-byte T, a 32-byte H1, and a variable-length compressed data body.

[0117] After receiving the data, the booster station performs a four-step verification:

[0118] Determine if the time stamp T deviates from the system time by ≤5s; SHA-256 hash value H2 is obtained by concatenating the source node identifier ID with the timestamp T; compare whether hash value H1 and hash value H2 are consistent; verify the CRC32 code of the compressed data body.

[0119] If any step fails, the data packet is discarded and a security event log is generated.

[0120] It is understood that the technical solution presented in this invention deploys relay modules using wind turbines as nodes, and adaptively networks based on geographical coordinates and signal strength; elects cluster head nodes to establish a tree-mesh hybrid topology; source nodes send routing requests, establish data transmission paths, monitor performance, and trigger retransmissions; data is transmitted in a hierarchical manner to ensure low latency for real-time data and high throughput for logs; the cluster head preprocesses and compresses data and adds security tags before forwarding. This invention solves the signal interruption caused by blade occlusion, reduces the latency of critical commands through hierarchical routing and composite index evaluation, improves log transmission efficiency through multi-path fountain code technology, eliminates service blocking problems, reduces energy consumption through sleep scheduling and compression algorithms, enhances data security, extends network lifetime, and reduces the total cost of ownership of the communication system.

[0121] In another embodiment, see Figure 3 and Figure 4 A long-distance communication system for wind farms based on a wireless ad hoc network is provided, for performing the method described in any one of the above methods, including:

[0122] The node deployment module is installed on the top of each wind turbine nacelle. It integrates a dual-frequency wireless communication unit, a high-precision positioning unit, and an environmental monitoring sensor to perform hardware self-tests. If the self-test fails, it triggers an audible and visual alarm and blocks network access.

[0123] During hardware self-test, verify whether the horizontal error of the geographic coordinates is less than 2 meters, whether the antenna VSWR is less than 1.8, and whether the temperature is within the normal range.

[0124] The topology management module runs a distributed election protocol and optimization algorithm to dynamically elect cluster head nodes based on the neighbor table and link quality index. It calculates the election weight by combining three indicators: the remaining power percentage of the node, the number of effective neighbors, and the minimum number of hops to the booster station. It generates a hybrid topology of tree backbone and mesh redundant links and forces vertically adjacent wind turbines within a 500-meter distance to establish direct connection channels.

[0125] The routing management module has a built-in service hierarchy engine and path evaluator. It is used to calculate reliability indicators when processing routing request packets. If the reliability indicators meet the standard (for example, a threshold of 0.7 is set, and routing request packets will only be forwarded if the indicator is greater than 0.7), the routing request packet is forwarded, and a path is reserved for the highest priority service to preempt the channel.

[0126] The data transmission module, including a fountain code encoder and a multi-path scheduler, is used to encode batch log data in fragments and add dynamic redundancy, utilizing multiple data transmission paths for parallel transmission. For example, it can allocate data to three independent paths with a transmission latency difference of no more than 20 milliseconds for parallel transmission.

[0127] The edge processing module, deployed at the cluster head node, integrates a data compression engine and a security tag generation unit. It performs spatiotemporal differential coding, dictionary compression, and entropy coding secondary compression, adding millisecond-level timestamps and source node-bound hash tags to data packets. Edge intelligent processing filters invalid monitoring data using a ResNet-8 anomaly detection model, and, in conjunction with the LZW-Hybrid compression algorithm, effectively improves bandwidth utilization, enabling limited wireless resources to carry high-value information.

[0128] It should be noted that the edge processing module includes:

[0129] The security verification unit, located on the booster station server, is equipped with a true random number generator and a password processor to perform four-step verification:

[0130] The deviation between the timestamp of the verification data packet and the system clock should not exceed 5 seconds.

[0131] Recalculate the SHA-256 hash value of the source node identifier concatenated with the timestamp;

[0132] Compare whether hash values ​​H1 and H2 are the same;

[0133] Verify the CRC32 code of the compressed data body;

[0134] The blockchain evidence storage unit is used to build a hash tree for the data after the four-step verification is passed, according to the 10-minute time intervals. The root of the tree is written into the distributed ledger through the consensus mechanism, providing an integrity verification interface.

[0135] The exception handling unit is used to discard data packets that fail the four-step verification and generate encrypted audit logs, recording the fault type, source node, and occurrence time.

[0136] The technical solution shown in this embodiment reduces the time spent on log file transmission through multi-path fountain code transmission technology, completely eradicating the industry problem of low-priority services blocking high-urgent instructions. The combined design of the hibernation scheduling mechanism and supercapacitor backup reduces the energy consumption of non-cluster head nodes, increases the continuous working time in windless environments, and extends the network lifetime.

[0137] This technical solution completely solves the millisecond-level signal interruption problem unique to wind farms through the synergistic effect of blade occlusion prediction model and directional antenna beam tracking. It reduces the link packet loss rate caused by blade rotation to less than 5%, improves single-hop communication availability to industrial-grade standards, and grants path preemption rights to emergency shutdown commands through a hierarchical routing protocol. Combined with the dynamic evaluation mechanism of composite reliability index (CI), it greatly reduces the end-to-end latency of critical commands.

[0138] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0139] It should be noted that in the description of this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means at least two.

[0140] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

[0141] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0142] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0143] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0144] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.

[0145] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0146] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A long-distance communication method for wind farms based on wireless ad hoc networks, characterized in that, include: Within the wind farm, deploy multi-hop relay wireless communication modules with each wind turbine as a node; The relay wireless communication module executes an adaptive networking protocol based on geographic coordinates and real-time signal strength. After the node starts up, it broadcasts a beacon frame containing location, device ID and communication capabilities. After receiving the beacon frame, neighboring nodes build a neighbor table and calculate the link quality index. Obtain all neighbor tables and link quality indices, and dynamically elect a cluster head node by combining the link quality index and geographical location information through a distributed election algorithm. The cluster head node is used to coordinate intra-cluster communication and cross-cluster routing scheduling, and establish a tree-mesh hybrid topology with the booster station central server as the root node. The source node sends a routing request packet to the root node. Intermediate nodes calculate the reliability index of the path based on the link quality prediction model. If the reliability index meets the standard, the routing request packet is forwarded. A hierarchical routing protocol is used to establish a data transmission path. After receiving the first valid routing request packet, the booster station central server returns a routing response along the reverse path, establishes a data transmission path, and evaluates the transmission performance of the path. When a delay > 100ms or a packet loss rate > 10% is detected, route retransmission is automatically triggered. The system retrieves the data content of the routing request packet and enables direct transmission of the real-time monitoring data of the wind farm using the UDP protocol. For batch fault logs, it adopts the fragmented TCP protocol combined with fountain code encoding, utilizes multiple data transmission paths for parallel transmission, and adjusts the data fragment size and retransmission number according to the network congestion status. The cluster head node performs multi-level data preprocessing to eliminate redundant information, runs an improved LZW-Hybrid compression algorithm to losslessly compress the data sent by other nodes in the cluster to obtain data packets, adds a timestamp and a SHA-256 hash value label based on the source node ID to each data packet, generates verifiable data units, and forwards them to the booster station. The booster station then sends information to complete long-distance communication of the wind farm.

2. The method according to claim 1, characterized in that, Within the wind farm, multi-hop relay wireless communication modules are deployed with each wind turbine as a node, including: A multi-hop relay wireless communication module is deployed on the top of each wind turbine nacelle; After the relay wireless communication module starts up, it performs a hardware self-test process, including: Perform a location verification to confirm the validity of GPS / BeiDou coordinates. If the location is out of tolerance, trigger a level 1 alarm. Perform RF diagnostics to measure the antenna VSWR. If the antenna VSWR is >1.8 or the receiver sensitivity is < -110dBm, triggering a level 2 alarm; Real-time monitoring of the ambient temperature surrounding the relay wireless communication module.

3. The method according to claim 1, characterized in that, The election of the cluster head node also includes: A genetic algorithm is used to dynamically adjust the election weight of the cluster head node. The weight factors for the election weight of the cluster head node include: the node's remaining power, historical link stability, and the number of hops with the booster station. The weights are recalculated every 6 hours, and the election of cluster head nodes is re-executed based on the calculated weights. When a new node is added, the topology information is updated through restricted flooding broadcast, and the flooding radius is set to 3 hops according to the wind farm density; When topology splits, an emergency networking mode is activated, forming a temporary relay group composed of the three nearest nodes, and Turbo coding is used to enhance the decoding capability of weak signals.

4. The method according to claim 1, characterized in that, When forwarding the routing request packet, the intermediate node also includes: Intermediate nodes calculate the forwarding probability using the following formula, and forward the routing request packet according to the forwarding probability; P = min(1, LQI / 85) Where P is the forwarding probability and LQI is the link quality index; When evaluating the transmission performance of a path, the following should be included: The composite index is calculated using the following formula. If the composite index CI ≤ 0.7, the data transmission path is unqualified, and route retransmission is triggered. CI=0.6×PRR+0.3×(1-Delay / Dmax)+0.1×ETX Where PRR is the packet reception rate, Dmax is the maximum allowed delay, Delay is the transmission delay of the current path, and ETX is the expected number of transmissions.

5. The method according to claim 1, characterized in that, During data transmission, the following are included: Define a three-level routing priority: emergency stop commands are the highest priority, SCADA data is the medium priority, and log files are the lowest priority. When the highest priority data transmission is executed, the low priority data transmission is interrupted.

6. The method according to claim 1, characterized in that, Batch fault logs are processed using a fragmented TCP protocol combined with fountain code encoding, and transmitted in parallel via multiple data transmission paths, including: The batch fault log data is fragmented, and the fragment size is dynamically adjusted within the range of 128B to 1KB based on the real-time network throughput. RaptorQ fountain codes are used to encode fragments, generating a set of encoded symbols, with the proportion of redundant symbols set to 15% to 35%. During multipath transmission, the encoded symbols are allocated to three independent paths for parallel transmission. The receiver decodes the original data based on the received k+1 symbols, where k is the original number of fragments. When decoding fails, only the missing symbol index is retransmitted, and the upper limit of the number of retransmissions is set according to the channel signal-to-noise ratio.

7. The method according to claim 1, characterized in that, The cluster head node performs multi-level data preprocessing to eliminate redundant information and runs an improved LZW-Hybrid compression algorithm to perform lossless compression of data packets, including: The cluster head node establishes a dynamic dictionary window to perform LZW encoding on the input data stream; Perform Huffman compression on the LZW encoded data; To address the spatiotemporal correlation of SCADA data, differential coding preprocessing is added: for sensor data with a change of <1% within 5 consecutive frames, only the full value of the first frame and the difference between subsequent frames are stored; After compression, a compression metadata header is added, which includes the original length, compression version, and checksum.

8. The method according to claim 7, characterized in that, Each data packet is labeled with a timestamp and a SHA-256 hash value based on the source node ID, generating a verifiable data unit before being forwarded to the booster station, including: When the cluster head node generates a data packet, it uses a hardware true random number generator to obtain the current millisecond-level timestamp T, concatenates the source node ID with the timestamp T, and calculates the SHA-256 hash value H1. The data packet structure includes: a 2-byte packet header identifier, a 4-byte T, a 32-byte H1, and a variable-length compressed data body. After receiving the data, the booster station performs a four-step verification: Determine if the time stamp T deviates from the system time by ≤5s; SHA-256 hash value H2 is obtained by concatenating the source node identifier ID with the timestamp T; compare whether hash value H1 and hash value H2 are consistent; verify the CRC32 code of the compressed data body. If any step fails, the data packet is discarded and a security event log is generated.

9. A long-distance communication system for wind farms based on a wireless ad hoc network, characterized in that, For performing the method as described in any one of claims 1 to 8, comprising: The node deployment module is installed on the top of each wind turbine nacelle. It integrates a dual-frequency wireless communication unit, a high-precision positioning unit, and an environmental monitoring sensor to perform hardware self-tests. If the self-test fails, it triggers an audible and visual alarm and blocks network access. The topology management module runs a distributed election protocol and optimization algorithm to dynamically elect cluster head nodes based on the neighbor table and link quality index. It calculates the election weight by combining three indicators: the percentage of remaining power of the node, the number of effective neighbors, and the minimum number of hops to the booster station. It generates a hybrid topology of tree backbone and mesh redundant links and forces vertically adjacent wind turbines within a 500-meter distance to establish direct connection channels. The routing management module has a built-in business hierarchy engine and path evaluator, which is used to calculate reliability indicators when processing routing request packets. If the reliability indicators meet the standards, the routing request packet is forwarded and a path is reserved for the highest priority service to preempt the channel. The data transmission module, which includes a fountain code encoder and a multi-path scheduler, is used to encode batch log data in segments and add dynamic redundancy, and to transmit the data in parallel using multiple data transmission paths. The edge processing module, deployed on the cluster head node, integrates a data compression engine and a security tag generation unit. It is used to perform spatiotemporal differential encoding, dictionary compression, and entropy encoding secondary compression, and adds millisecond-level timestamps and source node binding hash tags to data packets.

10. The system according to claim 9, characterized in that, The edge processing module includes: The security verification unit, located on the booster station server, is equipped with a true random number generator and a password processor to perform four-step verification: The deviation between the timestamp of the verification data packet and the system clock should not exceed 5 seconds. Recalculate the SHA-256 hash value of the source node identifier concatenated with the timestamp; Compare whether hash values ​​H1 and H2 are the same; Verify the CRC32 code of the compressed data body; The blockchain evidence storage unit is used to build a hash tree for the data after the four-step verification is passed, according to the 10-minute time intervals. The root of the tree is written into the distributed ledger through the consensus mechanism, providing an integrity verification interface. The exception handling unit is used to discard data packets that fail the four-step verification and generate encrypted audit logs, recording the fault type, source node, and occurrence time.

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