A photovoltaic device communication method, system and electronic device based on a wireless mesh network

Abstract

This invention relates to the field of communication network technology, and in particular to a communication method, system, and electronic device for photovoltaic (PV) equipment based on a wireless mesh network. The method is applied to a first node in the mesh network, where the first node is a PV device or a root node. It includes broadcasting a node joining signal, which contains a network identifier and is used to request unconnected devices to join the mesh network where the first node is located. This invention automatically networks PV devices with built-in mesh modules, forming a decentralized mesh topology. This effectively solves problems such as high deployment costs of wired networks, single-point failures in star topologies, and limited single-hop distance. Nodes are interconnected via multiple hops and possess routing self-healing capabilities. Multiple root nodes can provide redundant exits, ensuring reliable communication. Simultaneously, encryption authentication is introduced to ensure access security. Thus, this invention achieves high reliability, low cost, and flexible deployment of the PV field communication network.

Description

Technical Field

[0001] This invention relates to the field of communication network technology, and in particular to a communication method, system and electronic device for photovoltaic equipment based on a wireless mesh network. Background Technology

[0002] In photovoltaic power plants or distributed photovoltaic systems, it is typically necessary to transmit data from field devices such as tracking controllers, inverters, and wind speed sensors to a monitoring center and receive remote control commands. Currently, the mainstream communication network architectures can be divided into two main categories: wired and centralized wireless. Wired methods mainly include RS485 bus (using the Modbus RTU protocol) and industrial Ethernet (using the Modbus TCP / IP protocol), while centralized wireless methods often use short-range wireless technologies such as LoRa, aggregating data through a gateway before uploading.

[0003] While wired connections, such as RS485 bus or industrial Ethernet, provide stable and reliable communication links, their deployment requires laying a large number of communication cables. This not only results in high installation costs and complex construction processes, but also makes rewiring extremely difficult when equipment locations change, hindering adaptation to dynamic adjustments in the photovoltaic field's equipment layout. Centralized wireless connections typically employ a star topology, where all devices connect to a central gateway via a single hop, which then handles data aggregation and transmission. This architecture suffers from a significant single point of failure: if the central gateway fails, communication across the entire network is interrupted. Furthermore, photovoltaic fields are often open environments with numerous sources of electromagnetic interference, making wireless signals susceptible to obstruction and attenuation. The limited single-hop transmission distance often necessitates the addition of relay nodes or multiple gateways to achieve full coverage, increasing system costs and maintenance complexity.

[0004] In summary, existing photovoltaic (PV) equipment communication networks cannot simultaneously meet the requirements of flexible networking without gateways and high-stability self-healing. Therefore, there is an urgent need to introduce a new network mechanism to enhance the autonomy and robustness of PV equipment interconnection, ensuring reliable and efficient data transmission even in complex environments. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a photovoltaic device communication method, system and electronic device based on a wireless mesh network.

[0006] In a first aspect, embodiments of the present invention provide a photovoltaic device communication method based on a wireless mesh network, applied to a first node in the mesh network, wherein the first node is a photovoltaic device or a root node, comprising: The broadcast node join signal contains a network identifier and is used to request devices that are not yet on the network to join the Mesh network where the first node is located. The network access request is received by the second node after it receives the node join signal. The second node is any photovoltaic device that has not yet joined the Mesh network. The network access request contains the device information of the second node. Based on the device information, determine whether the second node meets the preset network access conditions; If the second node is determined to meet the network entry requirements, then the second node is added to the Mesh network, and a network level and parent node information are assigned to the second node. It periodically exchanges beacon frames with neighboring nodes. The beacon frames contain the network level, neighbor list and link quality parameters of the local node. The local routing table is updated based on the received beacon frames, and the paths to other root nodes and child nodes in the Mesh network are dynamically calculated based on the updated routing table. When the first node needs to send data, it determines the target transmission path to the target node based on the updated routing table, and forwards the data to the target node via single hop or multi hop; the target node includes the root node or other photovoltaic device nodes.

[0007] In conjunction with the first aspect, the device information includes the device type identifier and the network protocol version supported by the second node; The steps for determining whether a second node meets the preset network access conditions based on device information include: If the device type identifier belongs to the preset set of photovoltaic device types, and the network protocol version supported by the second node is compatible with that of the first node, then the second node is determined to meet the grid access conditions.

[0008] In conjunction with the first aspect, network layer and parent node information are assigned to the second node, including: Send a network access confirmation message to the second node. The network access confirmation message contains the root node identifier, the target value of the first node's network layer plus a preset value as the second node's network layer, and the first node's MAC address as the second node's parent node information.

[0009] In conjunction with the first aspect, the method also includes: When the received signal strength of a link is detected to be lower than the first threshold, or the packet loss rate is higher than the second threshold, or the link is interrupted, the routing algorithm is rerun to select a new next-hop node as an alternative path.

[0010] In conjunction with the first aspect, it also includes: Obtain the operating status data of the photovoltaic equipment where the first node is located; Operational status data is classified into categories according to preset priorities, with alarm data having the highest priority. For alarm data, a multi-path redundant transmission method is adopted, which sends the data to the target node simultaneously through two or more different paths.

[0011] In conjunction with the first aspect, the first node is the root node; the method also includes: If the communication link between the root node and the external network fails, and there are other root nodes in the Mesh network, an exit switch notification is broadcast to the other root nodes and child nodes in the Mesh network, instructing each node to switch to another available root node for data upload.

[0012] In conjunction with the first aspect, it also includes: Encryption mechanisms are used to protect information transmitted within the Mesh network; When a new node joins the network, it is authenticated using a pre-shared key or digital certificate. After joining the network, if the first node is the root node, a random number is generated as a new network key, and the new network key is encrypted and broadcast to all nodes in the Mesh network. The current network key of each node is updated based on the new network key, which is used to encrypt information transmitted within the Mesh network.

[0013] Secondly, the present invention provides a photovoltaic device communication system based on a wireless mesh network, comprising: Multiple photovoltaic devices, each serving as a child node of a mesh network, are configured to perform the methods described above. At least one root node, which has an interface for communicating with the external network, is configured as the data aggregation point and external network exit point of the Mesh network; Once powered on, multiple photovoltaic devices automatically run the Mesh networking protocol, interconnecting with each other through the broadcast and response of node joining signals to form a mesh topology. Data is transmitted between child nodes via single-hop or multi-hop wireless links, and finally, data interaction with the external network is achieved through the root node.

[0014] The second aspect of the system includes at least two root nodes; When the communication link between one of the root nodes and the external network fails, the other root nodes and child nodes in the Mesh network automatically switch to the remaining available root nodes to upload data.

[0015] Thirdly, the present invention provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor runs the computer program to cause the electronic device to perform the above-described method.

[0016] Fourthly, the present invention provides a readable storage medium storing computer program instructions, which are read and executed by a processor to perform the above-described method.

[0017] The embodiments of the present invention bring the following beneficial effects: The present invention provides a photovoltaic equipment communication method, system and electronic equipment based on a wireless mesh network. Through the automatic networking of photovoltaic equipment with built-in mesh modules, a decentralized mesh topology is formed, which effectively solves the problems of high cost of wired deployment, single point of failure in star topology and limited single-hop distance; multi-hop interconnection between nodes and routing self-healing capability, multiple root nodes can provide redundant exits to ensure communication reliability; at the same time, encryption authentication is introduced to ensure access security; thus, high reliability, low cost and flexible deployment of photovoltaic field communication network are achieved.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 A flowchart illustrating a photovoltaic device communication method based on a wireless mesh network, provided in an embodiment of the present invention; Figure 2 A schematic diagram of the communication network topology of photovoltaic devices based on a Mesh network provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the electronic device structure provided in an embodiment of the present invention.

[0022] Figure label: 130 - Processor, 131 - Memory, 132 - Bus, 133 - Communication interface. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] To facilitate understanding of this embodiment, the technical terms used in this invention will be briefly introduced below.

[0025] Mesh network: A wireless multi-hop network architecture where each node not only acts as a data terminal but also has routing capabilities, forwarding data to other root nodes and child nodes. Nodes are interconnected via wireless links, forming a mesh topology, and possess characteristics such as self-organization, self-healing, and redundant paths.

[0026] Node: In this invention, it refers to a photovoltaic device or root node connected to the Mesh network. Each node has a built-in wireless Mesh communication module that can send, receive, and forward data.

[0027] Photovoltaic equipment: refers to various field devices in photovoltaic power plants, including but not limited to inverters, tracking controllers, wind speed sensors, etc. These devices become sub-nodes of the Mesh network after having built-in wireless Mesh communication modules.

[0028] Root node: A special node in a mesh network, deployed on the transformer side, with an interface for communication with external networks (such as a monitoring center), and responsible for data aggregation and external network egress. The root node can be a standalone device or can be a photovoltaic device with the corresponding capabilities.

[0029] Child nodes: In contrast to the root node, they refer to ordinary photovoltaic device nodes in the Mesh network other than the root node. They are responsible for collecting field data and uploading it to the root node through a multi-hop method, while also receiving control commands from the root node.

[0030] Mesh Lite root node: refers to the simplified Mesh network root node implementation in this embodiment, which is responsible for network construction, hierarchical allocation, data aggregation and forwarding functions.

[0031] Backup parent node: refers to a backup parent node that is pre-established and maintained by the child node outside of the current primary parent node, for quick switching when the primary parent node fails.

[0032] Node Joining Signal: A signal broadcast on a preset channel after a node powers on to request to join the Mesh network. It usually contains information such as the network identifier ID and is used to be discovered by existing nodes.

[0033] Network access request: After receiving the node join signal, the device that has not joined the network returns a request message to the sender, which contains device information (such as device type identifier, supported network protocol version, etc.) to apply to join the network.

[0034] Beacon frames: Control frames periodically broadcast by nodes for neighbor discovery and link quality maintenance. The content typically includes the node's network layer, neighbor list, and link quality parameters (such as RSSI and packet loss rate).

[0035] Network hierarchy: Used to identify the number of hops a node is in a mesh network topology from the root node. The root node hierarchy is typically defined as 0, its direct child node hierarchy is 1, and so on. Network hierarchy helps prevent routing loops and optimize path selection.

[0036] Parent node: In a hierarchical mesh network, the node that provides network access to child nodes. Child nodes typically use the parent node as the first hop for upstream data transmission.

[0037] Routing table: A table maintained locally by a node to guide data forwarding, recording next-hop information, path metrics, etc., for each target node.

[0038] Link quality parameters: Indicators used to evaluate the reliability of wireless links, including Received Signal Strength Indicator (RSSI), Signal-to-Noise Ratio (SNR), Packet Loss Rate, Round Trip Time, etc.

[0039] Self-healing routing: When a Mesh network detects a degradation or interruption in link quality, it automatically triggers route recalculation to find alternative paths to maintain communication.

[0040] Multiple exit fault tolerance: Configure multiple root nodes as external network exits. When one exit fails, the network automatically switches to other available exits to ensure the continuity of data upload.

[0041] Neighboring nodes: Other nodes that have a direct wireless link with this node and can communicate directly are also called neighboring nodes.

[0042] Multi-path redundancy transmission: A mechanism that improves transmission reliability by sending the same data simultaneously through two or more non-overlapping paths for high-priority data (such as alarm information).

[0043] Encryption authentication mechanism: This includes authentication of devices when they join the network (using pre-shared keys or digital certificates) and encryption protection of network communication data to prevent unauthorized devices from accessing the network and data leakage.

[0044] Network key: A symmetric key shared by all nodes in a Mesh network for encrypting communication data, which is updated and securely distributed by the root node periodically.

[0045] After introducing the technical terms involved in this invention, the application scenarios and design concepts of the embodiments of this invention will be briefly described below.

[0046] Traditional communication solutions have obvious drawbacks: wired methods (such as RS485 bus and industrial Ethernet) require the laying of a large number of cables, resulting in high construction costs and poor flexibility; centralized wireless methods (such as LoRa) mostly use star topology, which has the potential for single-point failures and is limited by single-hop transmission distance and complex environmental interference. It often requires the addition of repeaters or multiple gateways to achieve full coverage, which significantly increases system costs and maintenance complexity.

[0047] Based on this, embodiments of the present invention provide a photovoltaic device communication method and system based on a wireless mesh network.

[0048] Example 1 This invention provides a communication method for photovoltaic devices based on a wireless mesh network, applied to the first node in the mesh network, where the first node is a photovoltaic device or a root node. Combined with... Figure 1 As shown, the method includes: S110, Broadcast Node Join Signal; wherein, the node join signal contains a network identifier and is used to request devices that have not yet joined the network to join the Mesh network where the first node is located.

[0049] Understandably, this method is applied to the first node in a mesh network. This first node can be a photovoltaic device (such as an inverter, tracking controller, wind speed sensor, etc.) or a root node serving as the network egress. In step S110, when the photovoltaic device or root node powers on, its built-in WiFi wireless communication module broadcasts a node joining signal on a preset channel. This node joining signal contains a network identifier ID, used to identify the mesh network to which it belongs. Devices that have not yet joined the network can discover the existence of existing devices in the current network by listening to this channel, thereby triggering the subsequent network joining process. This process achieves automatic device discovery without manual intervention.

[0050] S120: Receive the network access request returned by the second node after receiving the node join signal. The second node is any photovoltaic device that has not yet joined the Mesh network. The network access request contains the device information of the second node.

[0051] A second node that has not yet joined the network (such as a newly installed inverter) will send a network joining request back to the first node after receiving a node join signal broadcast by the first node. This request carries the second node's device information, such as device type identifier, supported network protocol versions, and MAC address. The first node, as an existing node in the network, is responsible for processing the new node's network joining request.

[0052] S130, based on device information, determines whether the second node meets the preset network access conditions.

[0053] The first node authenticates and verifies the legitimacy of the second node based on the received device information. Preset network access conditions may include: whether the device type belongs to the photovoltaic device set (such as inverters, tracking controllers, etc.), whether the supported network protocols are compatible with the current network, and whether authentication is performed via a pre-shared key or digital certificate. This step ensures that only legitimate and compatible devices can join the Mesh network, preventing unauthorized devices from accessing and ensuring network security.

[0054] S140, if it is determined that the second node meets the network entry conditions, then the second node is added to the Mesh network, and network layer and parent node information are assigned to the second node.

[0055] Once the first node confirms that the second node meets the network entry requirements, it will include it in the current mesh network. The first node sends a network entry confirmation message to the second node, which includes the root node identifier, network layer assignment, and parent node information. Typically, the second node's network layer is set to the first node's network layer plus 1, and the parent node information is set to the first node's MAC address. In this way, each node in the network clearly understands its position in the topology and its connection relationship with higher-level nodes, forming a hierarchical mesh structure.

[0056] S150: Periodically exchange beacon frames with neighboring nodes. The beacon frames contain the network level, neighbor list and link quality parameters of this node.

[0057] All nodes already in the network periodically broadcast beacon frames for neighbor discovery and link maintenance. The beacon frame contains the node's current network level, a list of known neighboring nodes, and link quality parameters with each neighbor (such as Received Signal Strength Indicator (RSSI), packet loss rate, etc.). Nodes exchange this information to stay aware of dynamic changes in the network topology.

[0058] S160, update the locally maintained routing table based on the received beacon frames, and dynamically calculate the paths to other root nodes and child nodes in the Mesh network based on the updated routing table.

[0059] Upon receiving a beacon frame from a neighboring node, each node updates its locally maintained neighbor information and link quality data, and refreshes its routing table accordingly. Based on a distributed routing protocol, nodes can dynamically calculate the optimal path to other root and child nodes in the mesh network. When a link quality degradation (e.g., RSSI below a threshold, increased packet loss rate) or link interruption is detected, the node automatically triggers route recalculation to find an alternative path. This mechanism endows the mesh network with self-healing capabilities, ensuring that communication continues even in the event of node failure or environmental changes.

[0060] S170, when the first node needs to send data, it determines the target transmission path to the target node according to the updated routing table, and forwards the data to the target node via single hop or multi hop; wherein, the target node includes the root node or other photovoltaic device nodes.

[0061] When the first node, acting as the source node, needs to send data, it first queries the routing table to determine the transmission path to the target node. If the target node is the root node, the data is typically status data collected by the photovoltaic equipment (such as power generation, equipment status, etc.), which needs to be uploaded to the monitoring center. If the target node is another photovoltaic equipment node, the data may be control commands or configuration information for remote control. The data is forwarded according to the next-hop node indicated by the routing table, possibly through multiple hops of intermediate nodes, and finally reaches the target node. During this process, each intermediate node continues to forward data according to its own routing table until the data reaches its destination. If the target node is the root node, after receiving the data, the root node uploads the data to the monitoring center through its interface with the external network (such as ring network, fiber optic, 4G, etc.); conversely, if the root node receives a downlink command from the monitoring center, it forwards the command to the corresponding target photovoltaic equipment according to the routing table.

[0062] Through the above steps, the method provided by this invention realizes automatic networking, dynamic routing maintenance and reliable data transmission of photovoltaic equipment, effectively solving the problems of complex and costly wiring in traditional wired methods and the single point of failure in centralized wireless methods, and improving the flexibility and stability of the photovoltaic field communication network.

[0063] In conjunction with the first aspect, the device information includes a device type identifier and the network protocol version supported by the second node; step S130, which determines whether the second node meets the preset network access conditions based on the device information, specifically includes: S131, if the device type identifier belongs to the preset set of photovoltaic device types, and the network protocol version supported by the second node is compatible with that of the first node, then the second node is determined to meet the grid access conditions.

[0064] Specifically, after receiving a network access request from the second node, the first node parses the device type identifier and the network protocol version supported by that node. The preset set of photovoltaic device types is a list of legal devices pre-configured in the system. This set includes at least the type identifiers of common photovoltaic field devices such as inverters, tracking controllers, and wind speed sensors. The first node first checks whether the device type identifier belongs to this set to ensure that the device applying for network access is a legitimate device in the photovoltaic system, preventing non-photovoltaic devices (such as externally intrusive devices, irrelevant terminals, etc.) from accessing the Mesh network, thereby ensuring the network's exclusivity and security.

[0065] Secondly, the first node checks whether the network protocol version supported by the second node is compatible with its own. Since photovoltaic devices deployed at different times may support different versions of Mesh networking protocols or communication standards, protocol incompatibility may lead to communication failures or functional limitations between nodes. Therefore, the first node needs to confirm that the protocol versions of both nodes are consistent or that there is backward / forward compatibility. For example, if the first node supports protocol version V2.0, while the second node only supports V1.0, but V2.0 is backward compatible with V1.0, then it can be considered compatible; conversely, if the protocols are incompatible, the node is rejected from joining the network. This checking mechanism ensures that all nodes in the network can communicate using a unified "language," avoiding data parsing errors or functional deficiencies caused by protocol differences.

[0066] Only when both of the above conditions (valid device type and compatible protocol version) are met simultaneously will the first node determine that the second node meets the network access requirements and allow it to join the Mesh network. If either condition is not met, the network access request is rejected, and the first node can choose to return a rejection reason to the second node or ignore the request. Through this dual verification mechanism, the method of this invention effectively controls the legitimacy and compatibility of access devices while ensuring network openness and ease of use.

[0067] In conjunction with the first aspect, step S140 assigns network layer and parent node information to the second node, including: S141, send a network access confirmation message to the second node. The network access confirmation message includes the root node identifier, the target value of the first node's network layer plus a preset value as the second node's network layer, and the first node's MAC address as the second node's parent node information.

[0068] Specifically, once the first node determines that the second node meets the network entry requirements, it needs to send a network entry confirmation message to the second node. This message contains three key information elements to help the second node accurately locate its role and connection relationship in the Mesh network: First, the root node identifier. The network entry confirmation message contains the root node identifier of the current Mesh network, such as the root node's MAC address or a preset network ID. This information allows the second node to clearly identify the exit node of the entire network. Regardless of subsequent changes in the network topology, the second node always knows the final destination to which the data needs to be aggregated. Even if the first node itself is not the root node, the second node can indirectly learn the identity of the root node through this identifier, providing a foundation for subsequent route discovery and data uploading.

[0069] Second, network hierarchy. The first node adds a preset value to its own network hierarchy, which becomes the network hierarchy of the second node. In a typical mesh network hierarchical model, the root node's network hierarchy is usually defined as 0 (or 1), its direct child nodes' hierarchy is 1 (or 2), and so on. The preset value is usually 1, indicating that the network hierarchy increases by one level each time a parent-child relationship is established. In this way, the entire mesh network forms a hierarchical topology with the root node as the top layer, extending downwards layer by layer. The allocation of network hierarchy has the following functions: To prevent routing loops, nodes can determine the direction of data forwarding based on hierarchical information. Typically, they only forward uplink data to nodes at lower hierarchical levels (closer to the root node) and downlink data to nodes at higher hierarchical levels. Optimize path selection: when selecting a parent node or routing path, a node can prioritize nodes with higher hierarchical levels to shorten the number of transmission hops. To assist in topology management, operations and maintenance personnel can intuitively understand the network topology structure by viewing the network hierarchy of each node, which facilitates troubleshooting and performance optimization.

[0070] Understandably, through the allocation of the above three pieces of information, the second node clarifies the following key issues the moment it joins the network: A. By analyzing the network hierarchy, determine how far the second node is from the root node; B. Determine which node the data should be sent to first by using the parent node's MAC address; C. By identifying the root node, the location of the network's exit point can be clearly determined.

[0071] This allocation mechanism allows new nodes to quickly integrate into the existing network without a complex global topology discovery process. Simultaneously, as nodes continuously join, the entire mesh network automatically forms a hierarchical topology with the root node at the top and clearly defined parent-child relationships, laying the foundation for subsequent route maintenance and data forwarding. The resulting network topology diagram is as follows: Figure 2 As shown in the diagram, this figure visually illustrates the layered mesh network architecture from the monitoring center to the field equipment.

[0072] It should be noted that the preset value can be adjusted according to the actual network design. In standard Mesh networking, this value is usually set to 1, indicating that the network layer increases by one layer each time a parent-child relationship is established; however, in some special scenarios (such as when it is necessary to reserve layer space or realize layer jumps), it can also be set to other positive integers, and this application does not limit this.

[0073] like Figure 2 As shown, the entire network is divided into five layers from top to bottom, extending from the back-end monitoring center to the lowest-level field device nodes. Each layer is interconnected through wireless mesh links, forming a mesh topology that combines hierarchy and redundancy.

[0074] Specifically, the top layer of the network is the backend monitoring center, which is connected to Ethernet via a host computer (Modbus TCP protocol). Ethernet connects downwards to the Mesh Lite root node (ROOT). The root node is a special node in the Mesh network, deployed on the transformer side, and undertakes the core functions of network construction, hierarchical allocation, data aggregation, and forwarding. As the external exit point of the entire Mesh network, the root node is responsible for transmitting the aggregated uplink data to the monitoring center via Ethernet, while simultaneously receiving control commands from the monitoring center and distributing them to each child node in the network.

[0075] Below the root node are the second layer of child nodes, including multiple nodes such as C2n, A2n, and B2n. These nodes all have routing / relay functions, acting as both data source devices collecting their own photovoltaic data and routers forwarding data to lower-layer nodes. The second-layer nodes communicate directly with the root node, forming the backbone relay layer of the network and playing a crucial role in connecting the upper and lower layers.

[0076] Below the second layer of nodes, the network continues to expand downwards in layers: The third layer child nodes include nodes such as C3-a, A3-b, B3-a, and A3-a. They access the network with the second layer nodes as their parent nodes and continue to provide relay services to lower-level nodes.

[0077] The fourth layer of child nodes includes nodes such as B4-a and A4-a, which further extend the network coverage.

[0078] The fifth layer of child nodes includes the A5 node, which is the lowest leaf node and is mainly responsible for data collection and reporting. It no longer undertakes the function of relaying data to other root nodes and child nodes (or only has limited relay capabilities).

[0079] Through this layered expansion method, the network can cover a wide photovoltaic field area in the form of multi-hop relay, breaking through the distance limitation of single-hop wireless communication and realizing data access for long-distance devices.

[0080] Taking a third-layer node as an example, each third-layer node not only establishes a connection with its current primary parent node (such as a second-layer node), but also maintains one or more backup parent nodes (other second-layer nodes in the same layer or adjacent third-layer nodes). When the primary parent node's link quality degrades, is interrupted, or fails, the child node can automatically switch to the backup parent node and re-establish the communication path.

[0081] For example, in the diagram, node A3-a's primary parent node might be A2n, while B2n or C2n could serve as a backup parent node. When the link between A2n and A3-a fails, A3-a automatically switches to the backup parent node B2n, maintaining connection to the network and continuing data transmission. This mechanism endows the network with dynamic self-healing capabilities, effectively preventing communication interruptions caused by single points of failure.

[0082] This invention constructs a flexible, reliable, and low-cost photovoltaic equipment communication network by embedding a WiFi Mesh module in the photovoltaic equipment, which automatically forms a hierarchical mesh structure after the equipment is powered on; long-distance communication between nodes is achieved through multi-hop relay; self-healing is achieved through a backup parent node mechanism; and finally, all data converges to the root node and is uploaded to the monitoring center via Ethernet.

[0083] In conjunction with the first aspect, the method also includes: S210: When the received signal strength of a link is detected to be lower than the first threshold, or the packet loss rate is higher than the second threshold, or the link is interrupted, the routing algorithm is rerun and a new next-hop node is selected as the alternative path.

[0084] Specifically, in the complex environment of photovoltaic power plants, wireless signals are easily affected by factors such as equipment obstruction, electromagnetic interference, and weather changes, leading to dynamic fluctuations in link quality. To ensure the continuity and reliability of communication, this method introduces a dynamic routing maintenance mechanism based on link quality monitoring. Each node continuously monitors the communication link quality between itself and its neighboring nodes, with the main monitoring parameters including the following three: First, Received Signal Strength Indication (RSSI). RSSI is a key indicator of wireless signal strength; the lower the value (the larger the absolute value of the negative value), the weaker the signal. In photovoltaic fields, signal strength may gradually attenuate as the spacing between devices changes or obstacles appear. This method presets a first threshold (e.g., -85dBm). When a node detects that the RSSI of a link is consistently below this threshold, it determines that the link quality is insufficient to support stable communication and may be about to be interrupted.

[0085] Second, packet loss rate. Packet loss rate refers to the proportion of data packets lost during data transmission out of the total number of packets sent. Monitoring data from photovoltaic equipment typically requires reliable transmission, especially alarm information, which cannot be lost. This method presets a second threshold (e.g., 20%). When a node detects that the packet loss rate of a certain link exceeds this threshold, it indicates that the link has experienced severe congestion or interference, and continued use will affect data integrity.

[0086] Third, link interruption. Link interruption is the most serious fault state, characterized by a node failing to receive beacon frames or data acknowledgment messages from a neighboring node multiple times in a row. This usually means that the node has lost power, moved out of coverage, or has experienced a hardware failure. At this point, the link is completely unusable.

[0087] When any of the above conditions are triggered, the node immediately initiates a route recalculation mechanism, which includes the following process: First, the node marks the failed link as unavailable and removes it from the currently active routing table. Second, the node re-runs the distributed routing algorithm, recalculating paths to each target node based on the latest neighbor information and link quality data. During path selection, the node avoids failed or degraded links, prioritizing alternative paths with higher RSSI, lower packet loss rate, and moderate hop count. Finally, the node updates the calculated new next-hop node in its routing table and begins forwarding data using the new path.

[0088] For example, suppose node A in the network was originally sending data to the root node through node B, but node A detects that the RSSI of its link with node B is below a first threshold. Node A will then query its neighbor list and find that nodes C and D are also reachable, and the link quality is good. After node A re-runs the routing algorithm, it selects node C as the new next-hop node, and subsequent data will be transmitted via the path from A to C… and then to the root node. This switching process is completed in milliseconds, and upper-layer applications are almost unaware of it.

[0089] Through this mechanism, the method of this invention achieves the self-healing capability of the mesh network: when the quality of a link degrades or is interrupted, the network can automatically bypass the faulty area, re-plan the data path, and ensure that the data from the photovoltaic equipment can still be reliably transmitted to the monitoring center, or that control commands can still be delivered to the target equipment. This dynamic routing maintenance mechanism is particularly suitable for scenarios such as photovoltaic fields where nodes are dispersed and the environment is changeable, significantly improving the robustness and reliability of the communication network.

[0090] Furthermore, a node can maintain one or more backup parent nodes simultaneously during network entry and periodically exchange beacon frames with them to maintain link hot standby. When the primary parent node link fails, the node does not need to re-execute the complete network entry process, but directly switches to the backup parent node, achieving rapid self-healing.

[0091] In conjunction with the first aspect, the method also includes: S310: Obtain the operating status data of the photovoltaic equipment where the first node is located.

[0092] S320 classifies the operating status data according to preset priorities, with alarm data having the highest priority; In response to an alarm data transmission request, the S330 employs a multi-path redundancy transmission method, simultaneously transmitting data to the target node via two or more different paths.

[0093] The method provided by this invention also includes a differentiated processing mechanism for different types of data to improve the reliability of critical data transmission. Specifically, in step S310, the first node, acting as a photovoltaic device (such as an inverter, tracking controller, wind speed sensor, etc.), has a built-in wireless mesh communication module connected to the device's main control unit via a serial port or internal bus to collect real-time operating status data. This data includes, but is not limited to: power generation, DC voltage and current, AC output voltage and current, cumulative power generation, device temperature, fault codes, tracking angle, wind speed and direction, etc. The acquisition frequency can be configured according to actual needs; for example, routine status data can be reported every 5-15 minutes, while key parameters are monitored in real time. This data forms the basis for the photovoltaic power plant monitoring system to perform operational analysis, fault diagnosis, and performance evaluation.

[0094] Considering the varying importance and real-time requirements of data generated during photovoltaic power plant operation, step S320 of this method prioritizes the collected operational status data. Preset priorities are typically divided into multiple levels, for example: Highest priority (alarm data): This includes emergency events requiring immediate attention, such as equipment failures, overvoltage and overcurrent, power grid anomalies, and fire warnings. This type of data demands extremely low latency and extremely high reliability, and must be delivered to the monitoring center in a timely manner.

[0095] High priority (critical status data): such as device start / stop status, power fluctuations, communication anomalies, etc. Although not emergency alarms, they have a significant impact on operation and maintenance decisions and require reliable transmission.

[0096] Normal priority (routine monitoring data): such as periodic data like temperature, power generation, and wind speed, which allows for a certain delay and occasional packet loss.

[0097] Nodes assign priority tags to each piece of data according to preset rules, providing a basis for selecting subsequent transmission strategies. This hierarchical mechanism rationally allocates network resources by distinguishing the importance of data.

[0098] In step S320, when the first node generates or receives alarm data that needs to be sent (e.g., the inverter detects a DC arc fault), the node identifies that the data has the highest priority and triggers a multi-path redundancy transmission mechanism. This mechanism utilizes the multi-connectivity characteristics of a mesh network to simultaneously send the same alarm data to the target node (usually the root node, for uploading to the monitoring center) through two or more non-overlapping (or as independent as possible) paths. When calculating multiple available paths, the node can prioritize paths with non-overlapping intermediate nodes to minimize the impact of a single point of failure on all backup paths. If completely independent paths cannot be found, the path combination with the lowest overlap is selected first.

[0099] The specific implementation process includes the following sub-steps: The first node queries its local routing table to calculate multiple available paths to the target node. The path selection algorithm can consider the diversity of paths, for example, prioritizing paths with non-overlapping intermediate nodes to avoid a single point of failure affecting all backup paths simultaneously.

[0100] The first node copies the alarm data into multiple copies and adds a path identifier or sequence number to each copy so that the target node can perform deduplication.

[0101] The first node simultaneously sends alarm data through multiple selected paths. During transmission, intermediate nodes process the data according to normal forwarding rules, but may give priority to data packets carrying alarm identifiers (e.g., by inserting them at the head of the sending queue).

[0102] Upon receiving the first alarm data, the target node (root node) can immediately process it and upload it to the monitoring center. At the same time, it caches subsequent identical data packets to verify or discard duplicate packets, thus avoiding redundant reporting.

[0103] This multi-path redundancy transmission mechanism ensures that even if one path is interrupted due to interference, congestion, or node failure, alarm data can still be delivered promptly through other paths, greatly improving the success rate of alarm information transmission. This mechanism is particularly suitable for complex environments with numerous interference sources, such as photovoltaic power plants, ensuring that emergency events can be detected and handled by the monitoring center in a timely manner, thus guaranteeing the safe operation of the power plant.

[0104] It should be noted that for non-alarm data (such as ordinary priority data), nodes can use a single-path conventional transmission method to save network bandwidth and node power consumption. This differentiated processing strategy optimizes the overall network resource utilization efficiency while ensuring the reliability of critical services.

[0105] In conjunction with the first aspect, the first node is the root node; the method also includes: S410 If the communication link between the root node and the external network fails, and there are other root nodes in the Mesh network, then broadcast an exit switch notification to the other root nodes and child nodes in the Mesh network, instructing each node to switch to another available root node for data upload.

[0106] In the deployment of a mesh network in a photovoltaic power plant, to improve system reliability, two or more root nodes can be configured as network egress points. These root nodes are typically deployed on the transformer side and connected to the monitoring center via ring networks, fiber optics, 4G, etc., forming a redundant egress architecture. Under normal operation, multiple root nodes can load balance data transmission; when one root node fails, the remaining root nodes can take over the egress function, ensuring the continuity of data upload.

[0107] This step requires two conditions to be met simultaneously: Condition 1: Communication link failure between the root node and the external network. The root node continuously monitors its connection status with the external network (such as the monitoring center, ring network switch, etc.). Monitoring methods may include: periodically sending heartbeat packets to the external server and waiting for confirmation, detecting the physical layer link status (such as Ethernet connection failure), and monitoring the connectivity of the uplink gateway. When multiple consecutive detections fail or no external response is received within a preset time, it is determined that the communication link has failed. For example, when the root node uploads data through the ring network, if it detects that the switch port is down or the ping to the monitoring center IP times out, it considers the outbound link to be interrupted.

[0108] Condition 2: Other root nodes exist in the mesh network. Root nodes need to be aware of the existence of other available root nodes in the network. This information can be obtained through beacon frames periodically exchanged between nodes, which may contain an identifier indicating whether they are root nodes. Each root node maintains a list of other root nodes in the network, including their MAC addresses, network layers, link quality, and other information. This condition is satisfied if at least one other root node exists in the list.

[0109] The root node will only execute the subsequent broadcast notification steps if both of the above conditions are met simultaneously. If there are no other root nodes in the network, even if the node's exit point fails, it cannot switch over and must wait for fault recovery or manual intervention.

[0110] Once it is determined that an exit point needs to be switched, this root node immediately generates an exit point switching notification message and broadcasts it to all other root nodes and child nodes via the Mesh network. This notification message contains the following key information: Fault root node identifier: Indicates which root node in the network has experienced an exit failure, usually the MAC address or default ID of this node.

[0111] Available root node list: Information on other available root nodes maintained by this node, for each child node to use as a switching reference. Optionally, a recommended preferred root node can be marked.

[0112] Switchover Effective Time: Indicates when each node should stop sending uplink data to this node and switch to another root node. It is usually set to take effect immediately.

[0113] Broadcast messages are forwarded hop-by-hop to every node in the mesh network via a multi-hop transmission mechanism. To ensure high reliability, this notification can be configured to be sent repeatedly with higher priority.

[0114] In addition, other root nodes and child nodes in the Mesh network (including photovoltaic device child nodes and other root nodes) perform the following actions after receiving the exit switch notification: S410 marks the faulty root node as unavailable, removes it from its respective routing table, or lowers its priority.

[0115] S420 re-runs the routing algorithm, selecting a new root node as the target exit for data upload based on the list of available root nodes and the current link quality.

[0116] S430: For uplink data that is already waiting to be sent, if it has not yet been sent, the path is recalculated and sent to the newly selected root node; if it has been sent to the faulty root node but no acknowledgment has been received, the application layer policy is used to select retransmission or discard.

[0117] S440: After receiving the notification, other root nodes can adjust their own load status accordingly to prepare to receive the possible increase in data traffic.

[0118] Through this mechanism, when a node fails, the entire Mesh network can quickly detect the problem and automatically switch to another available exit, achieving transparent fault healing. Child nodes require no manual intervention and do not need to understand complex network topology changes, ensuring the continuity of data uploads from photovoltaic devices and significantly improving the system's reliability and fault tolerance.

[0119] It should be noted that brief communication interruptions or data buffering may occur during the outgoing link switching process, but these typically occur within seconds or even milliseconds, having minimal impact on the overall operation of the photovoltaic monitoring system. Meanwhile, to avoid the "ping-pong switching" effect (i.e., network oscillation caused by frequent root node online / offline cycles), appropriate delay and rollback mechanisms can be configured. For example, after a faulty root node recovers, it may not immediately switch back, but instead wait for a period of stability before rejoining load balancing.

[0120] In conjunction with the first aspect, the method also includes: The S510 employs an encryption mechanism to protect information transmitted within the Mesh network.

[0121] Specifically, as a critical infrastructure, the security of the communication network of photovoltaic power plants is paramount. To prevent data eavesdropping, tampering, or forgery, this method introduces an encryption protection mechanism on all communication links of the mesh network. This encryption mechanism covers all information transmitted in the network, including control signaling between nodes (such as beacon frames, network access requests, and routing updates), service data (such as photovoltaic equipment status information and control commands), and network management messages. The choice of encryption algorithm can be configured according to actual security requirements; for example, symmetric encryption algorithms such as AES-128 and AES-256 can be used to ensure the confidentiality and integrity of data transmission. By implementing encryption at the network layer or data link layer, even if the wireless signal is intercepted, attackers cannot decipher the original information content, thereby ensuring the security of photovoltaic equipment data.

[0122] When a new node joins the network, the S520 uses a pre-shared key or digital certificate for authentication.

[0123] In addition to encrypting transmitted data, this method also performs strict authentication on devices accessing the network to prevent unauthorized devices from joining the Mesh network. When a new node (such as a newly added inverter or tracking controller) initiates a network entry request, existing nodes in the network (usually its parent or root node) authenticate the new node. The authentication methods include the following two: Pre-shared key (PSK) method: All legitimate devices are configured with the same pre-shared key at the factory or before deployment. New nodes include authentication information encrypted with this key in their network access requests. Receiving nodes verify the correctness of the encrypted information to determine the legitimacy of the device. This method is simple and efficient, suitable for scenarios with batch deployments and moderate security requirements.

[0124] Digital certificate method: Each device has a built-in digital certificate issued by a trusted Certificate Authority (CA), which contains the device's identity information and public key. When a new node joins the network, it submits its digital certificate. Authentication nodes in the network verify the certificate's validity (including the certificate chain, validity period, revocation status, etc.) and verify whether the device possesses the corresponding private key through a challenge-response mechanism. This method offers higher security and is suitable for power plants with strict security requirements.

[0125] Regardless of the method used, only authenticated devices are allowed to join the Mesh network; otherwise, the request will be rejected. This step ensures network access security and prevents attackers from stealing data or launching attacks by spoofing devices to access the network.

[0126] After joining the network, if the first node is the root node, the S530 generates a random number as a new network key, encrypts the new network key, and broadcasts it to all nodes in the Mesh network.

[0127] To further enhance the security of network communication keys, this method introduces a dynamic key update mechanism. When a new node joins the network, or when the network reaches a preset operating period, the root node triggers the network key update process. The specific execution is as follows: First, confirm that the node performing this step is the root node (i.e., the first node is the root node). Only the root node has the authority to generate and distribute network keys, which ensures the centralization and authority of key management.

[0128] The root node uses a random number generator to generate a new random number, which serves as the new network key (e.g., a 128-bit or 256-bit random number). This key will be used for encryption protection of subsequent network communications.

[0129] To prevent the new network key from being stolen during broadcast, the root node needs to encrypt the key itself. The root node encrypts the new network key using an independent secure channel established when each node joins the network (e.g., a session key negotiated based on a pre-shared key or digital certificate) and then broadcasts it throughout the Mesh network. Because different nodes use different encryption keys, the broadcast message may actually contain multiple independently encrypted copies of the key, or it may use multicast encryption (such as group key encryption). In this way, only legitimate nodes can decrypt and obtain the new network key, while attackers, even if they intercept the broadcast message, cannot obtain the key content.

[0130] S540 updates the current network key of each node based on the new network key, which is used to encrypt information transmitted within the Mesh network.

[0131] Specifically, after receiving the encrypted new network key broadcast by the root node, all nodes in the Mesh network first decrypt it using their own stored session key (or private key) to obtain the plaintext of the new network key, and then replace their locally stored current network key with it. Thereafter, nodes encrypt data using the new network key when sending data and decrypt data using the new network key when receiving data. This update process takes effect synchronously across all nodes, ensuring the consistency and timeliness of communication keys within the network.

[0132] Regular key updates effectively prevent the risk of key leakage due to prolonged key use, while also excluding offline or invalid nodes from the network (because they cannot obtain updated keys). Combining network access authentication in step S520 and key broadcasting in step S530, this method constructs a complete Mesh network security system, including access authentication, transmission encryption, and dynamic key updates, comprehensively ensuring the security of photovoltaic device communication.

[0133] Secondly, the present invention provides a photovoltaic device communication system based on a wireless mesh network, comprising: multiple photovoltaic devices and a root node.

[0134] Each photovoltaic device acts as a child node of the Mesh network. The photovoltaic device has a built-in wireless Mesh communication module, which is configured to perform the method described above.

[0135] The root node has an interface for communicating with the external network and is configured as the data aggregation point and external network exit point of the Mesh network.

[0136] Once powered on, multiple photovoltaic devices automatically run the Mesh networking protocol, interconnecting with each other through the broadcast and response of node joining signals to form a mesh topology. Data is transmitted between child nodes via single-hop or multi-hop wireless links, and finally, data interaction with the external network is achieved through the root node.

[0137] The second aspect of this invention provides a system that, through its unique architectural design and the synergistic effect of its components, primarily comprises multiple photovoltaic devices as sub-nodes of a mesh network and at least one root node as the network exit. Each photovoltaic device has a built-in wireless mesh communication module configured to execute the communication method of the first aspect of this invention. Under this architecture, after power-on, the photovoltaic devices can automatically run the mesh networking protocol, discovering and connecting with each other through the broadcast and response of node join signals, forming a decentralized mesh topology without any manual intervention. This mechanism completely changes the drawbacks of traditional wired communication methods, which require laying a large number of cables, are complex to construct, and are costly, achieving true plug-and-play functionality and significantly reducing the deployment difficulty and operation and maintenance costs of the photovoltaic field communication network.

[0138] In a mesh topology, each child node can act as both a data source and a router, forwarding data to other root nodes and child nodes. Interconnectivity between any two nodes is achieved through single-hop or multi-hop wireless links. This multi-hop transmission mechanism effectively overcomes the distance limitations of single-hop wireless communication, enabling reliable communication even between distant devices via relay nodes. As the number of nodes increases, the network coverage automatically expands, creating a virtuous cycle of wider coverage with more nodes. This eliminates the need to deploy separate gateways for each area, significantly reducing hardware investment and maintenance costs.

[0139] Root nodes act as a bridge between the mesh network and external networks, undertaking the crucial functions of data aggregation and egress forwarding. Each root node has an interface for communication with the external network and can connect to the monitoring center via various methods such as ring networks, fiber optics, and 4G. All operational status data collected by photovoltaic devices is ultimately uploaded to the external network through the root nodes, while control commands issued by the monitoring center are also distributed to target devices through the root nodes. When multiple root nodes are configured in the system, egress load balancing and fault switching can be achieved, further improving the reliability of data upload. This architecture ensures compatibility with existing monitoring systems while providing redundancy for industrial applications with high reliability requirements.

[0140] Furthermore, since the wireless mesh communication module of each photovoltaic device is configured to execute the method described in the first aspect, this system naturally inherits several enhanced functions implemented by that method. In terms of security, the system employs multiple protection mechanisms, including network access authentication, encrypted data transmission, and dynamic network key updates, to prevent unauthorized devices from accessing the network and ensure the communication security of this critical infrastructure, the photovoltaic power station. Regarding data transmission reliability, the system can prioritize operational status data and employ multi-path redundant transmission for critical data such as alarms, transmitting it simultaneously to the target node via two or more different paths to ensure that emergencies can be promptly detected and handled by the monitoring center. In terms of network performance, the system can dynamically adjust the routing maintenance frequency according to network scale and topology changes, controlling communication overhead while ensuring link stability, adapting to applications with a large number of photovoltaic devices but small data volumes per node.

[0141] The photovoltaic equipment communication system based on a wireless mesh network provided by the second aspect of the present invention achieves comprehensive technical effects such as flexible networking, high stability and self-healing, wide-area coverage and reliable data transmission from multiple dimensions such as deployment convenience, communication reliability, coverage capability, security and key business assurance, providing a solid and reliable communication infrastructure for the intelligent operation and maintenance of photovoltaic fields.

[0142] In conjunction with the second aspect, the system includes at least two root nodes; When the communication link between one of the root nodes and the external network fails, the other root nodes and child nodes in the Mesh network automatically switch to the remaining available root nodes to upload data.

[0143] The second aspect of this invention provides a photovoltaic equipment communication system based on a wireless mesh network. Building upon the basic architecture, it further introduces a redundant configuration of multiple root nodes to enhance system reliability and fault tolerance. Specifically, the system includes at least two root nodes, each with an interface for communication with an external network, and configured as a data aggregation point and external network egress point for the mesh network. Under normal operating conditions, multiple root nodes can load balance the data upload task, each responsible for forwarding data from child nodes within its coverage area or as specified by the routing strategy. When the communication link between one root node and the external network fails, the system automatically triggers an egress switching mechanism. Other root nodes and child nodes in the mesh network (including photovoltaic equipment child nodes and other root nodes) quickly detect the fault and switch to other available root nodes for data upload, thereby ensuring the continuity of data upload and the overall reliability of the system.

[0144] The implementation of this multi-root node redundancy switching mechanism relies on the coordinated cooperation among the nodes within the system. First, the root node needs to have the ability to monitor the status of external network links in real time. Each root node continuously assesses its connection status with the external network by periodically sending heartbeat packets to the monitoring center, checking the physical layer link status, or monitoring the uplink gateway connectivity. When multiple consecutive checks fail or no external response is received for more than a preset time, the root node determines that its own egress link has failed.

[0145] Secondly, an effective state information exchange mechanism needs to be established between root nodes and between root nodes and child nodes. During the normal operation of the mesh network, each root node informs other root nodes and child nodes in the network of its own root node identity and outgoing link status through periodically broadcast beacon frames or other control messages. Each root node maintains a list of other available root nodes in the network, including their MAC addresses, network layers, link quality, and other parameters. Child nodes also learn about all existing root nodes and their status in the current network by listening to these broadcast messages.

[0146] When a root node detects a failure in its own egress link, it immediately triggers an egress switchover notification process. This root node generates an "egress switchover notification" message and broadcasts it to all other root nodes and child nodes via the mesh network. This notification message typically contains the following key information: the identifier of the failed root node (such as its MAC address or default ID), a list of other available root nodes (optional), and an indication of the switchover effective time. To ensure reliable transmission of the notification message, a strategy of repeated transmission or higher priority transmission can be employed, utilizing the multi-hop mechanism of the mesh network to forward the message level by level to every node in the network.

[0147] Upon receiving the egress switchover notification, other root nodes and child nodes (including child nodes and other root nodes) in the mesh network execute the corresponding switchover operations. For child nodes, the first step is to mark the failed root node as unavailable or lower its priority in the routing table. Then, based on the latest maintained list of available root nodes and the current link quality parameters, the routing algorithm is re-run to select a new root node as the target egress for data uploads. For uplink data that has been cached but not yet sent, if it was originally destined for the failed root node, the path is recalculated and sent to the newly selected root node. This switchover process is completed automatically with the support of the routing protocol, requiring no manual intervention and no need for child nodes to understand the complex network topology changes.

[0148] For other root nodes, upon receiving the exit switch notification, they will remove the failed root node from the collaboration list and prepare to receive potentially increased data traffic based on their own load. If necessary, they can broadcast their availability status to the network to guide more child nodes to choose them as the new exit. Multiple root nodes can form a redundancy relationship of mutual backup. When one exit fails, the remaining root nodes will share the original data upload task.

[0149] Thirdly, embodiments of the present invention provide an electronic device, combined with Figure 3 As shown, the electronic device includes a memory 131 and a processor 130. The memory 131 stores a computer program, and the processor 130 runs the computer program to make the electronic device perform the above-described method.

[0150] Furthermore, combined Figure 3 The electronic device shown also includes a bus 132 and a communication interface 133, with the processor 130, the communication interface 133 and the memory 131 connected via the bus 132.

[0151] The memory 131 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 133 (which can be wired or wireless), such as the Internet, wide area network, local area network, metropolitan area network, etc. The bus 132 may be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 3 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0152] Processor 130 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of processor 130 or by instructions in software form. Processor 130 may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this invention can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software module can reside in a mature storage medium in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory 131, and processor 130 reads the information in memory 131 and, in conjunction with its hardware, completes the steps of the method described in the foregoing embodiments.

[0153] Fourthly, embodiments of the present invention provide a readable storage medium storing computer program instructions, which are read and executed by a processor to perform the above-described method.

[0154] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and apparatus described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0155] Furthermore, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0156] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0157] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0158] Finally, it should be noted that the above embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A communication method for photovoltaic devices based on a wireless mesh network, characterized in that, The first node applied in a Mesh network, which is a photovoltaic device or the root node, includes: A broadcast node join signal is provided, which includes a network identifier and is used to request devices that are not yet on the network to join the Mesh network where the first node is located. The second node receives the network access request returned by the node after receiving the node joining signal. The second node is any photovoltaic device that has not yet joined the Mesh network. The network access request contains the device information of the second node. Based on the device information, determine whether the second node meets the preset network access conditions; If it is determined that the second node meets the network entry conditions, then the second node is added to the Mesh network, and a network layer and parent node information are assigned to the second node; It periodically exchanges beacon frames with neighboring nodes. The beacon frames contain the network level, neighbor list and link quality parameters of the current node. The local routing table is updated based on the received beacon frames, and the paths to other root nodes and child nodes in the Mesh network are dynamically calculated based on the updated routing table. When the first node needs to send data, it determines the target transmission path to the target node according to the updated routing table, and forwards the data to the target node via single hop or multi hop; wherein, the target node includes the root node or other photovoltaic device nodes.

2. The method according to claim 1, characterized in that, The device information includes a device type identifier and the network protocol version supported by the second node; The step of determining whether the second node meets the preset network access conditions based on the device information includes: If the device type identifier belongs to a preset set of photovoltaic device types, and the network protocol version supported by the second node is compatible with that of the first node, then the second node is determined to meet the network access conditions.

3. The method according to claim 1, characterized in that, The process of allocating network layer and parent node information to the second node includes: Send a network access confirmation message to the second node. The network access confirmation message includes the root node identifier, the target value of the network layer of the first node plus a preset value as the network layer of the second node, and the MAC address of the first node as the parent node information of the second node.

4. The method according to claim 1, characterized in that, The method further includes: When the received signal strength of a link is detected to be lower than the first threshold, or the packet loss rate is higher than the second threshold, or the link is interrupted, the routing algorithm is rerun to select a new next-hop node as an alternative path.

5. The method according to claim 1, characterized in that, Also includes: Obtain the operating status data of the photovoltaic equipment where the first node is located; The operational status data is classified into categories according to preset priorities, with alarm data having the highest priority. For alarm data, a multi-path redundant transmission method is adopted, which sends the data to the target node simultaneously through two or more different paths.

6. The method according to claim 1, characterized in that, The first node is the root node; the method further includes: If the communication link between the root node and the external network fails, and there are other root nodes in the Mesh network, an exit switching notification is broadcast to the other root nodes and child nodes in the Mesh network, instructing each node to switch to another available root node for data upload.

7. The method according to claim 1, characterized in that, Also includes: Encryption mechanisms are used to protect information transmitted within the Mesh network; When a new node joins the network, it is authenticated using a pre-shared key or digital certificate. After joining the network, if the first node is the root node, a random number is generated as a new network key, and the new network key is encrypted and broadcast to all nodes in the Mesh network. The current network key of each node is updated based on the new network key, which is used to encrypt information transmitted within the Mesh network.

8. A photovoltaic equipment communication system based on a wireless mesh network, characterized in that, include: Multiple photovoltaic devices, each of which serves as a child node of a mesh network, wherein the photovoltaic devices have a built-in wireless mesh communication module configured to perform the method as described in any one of claims 1-7; At least one root node, which has an interface for communicating with an external network and is configured as the data aggregation point and external network exit point of the Mesh network; Once powered on, the photovoltaic devices automatically run the Mesh networking protocol, interconnecting with each other through the broadcast and response of node joining signals to form a mesh topology. The child nodes transmit data through single-hop or multi-hop wireless links, and finally achieve data interaction with the external network through the root node.

9. The system according to claim 8, characterized in that, The system includes at least two root nodes; When the communication link between one of the root nodes and the external network fails, the other root nodes and child nodes in the Mesh network automatically switch to the remaining available root nodes to upload data.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method according to any one of claims 1 to 7.

Images