A ring network LoRa wireless communication method suitable for monitoring the state of a hydroelectric generator stator core

Abstract

The application discloses a kind of annular network LoRa wireless communication method and system suitable for hydroelectric generating set stator core state monitoring, for traditional wired wiring complex, star type wireless easy single point failure, strong magnetic metal closed environment communication is not stable and other problems, along the circumference of stator core equidistance layout monitoring node and convergence node, construct closed annular LoRa communication network;Node has data acquisition and relay forwarding function, determine bidirectional main and standby transmission path by link quality score, adopt hop-by-hop forwarding transmission data;Carry LoRa parameter self-adaptive adjustment mechanism to resist interference, to realize fault node automatic isolation and ring network reconstruction with heartbeat monitoring, cooperate with deep sleep low-power consumption management and data verification retransmission mechanism guarantee transmission reliable.The application is not dependent on center gateway, communication redundancy self-healing, strong anti-interference, low power consumption, can be in strong magnetic, strong vibration, metal closed working condition Stable transmission monitoring data, meet the long-term unattended online monitoring needs of hydroelectric generating set.

Description

Technical Field

[0001] This invention relates to the field of online monitoring of industrial equipment, and specifically to a LoRa wireless communication method for monitoring the status of the stator core of hydropower units. Background Technology

[0002] Hydropower is an important component of clean and renewable energy, and the long-term safe and stable operation of its core equipment, the turbine generator unit, is crucial. Online monitoring of the condition of critical components such as bearings and stators is fundamental to preventing equipment failures, enabling predictive maintenance, and ensuring the economic benefits and safety of the power plant.

[0003] Existing online status monitoring of stator cores mostly adopts wired transmission, which requires laying a large area of ​​data signal cables inside the stator core. This makes wiring difficult and construction complex. At the same time, the cables are prone to aging, poor contact, or even breakage under strong magnetic fields and long-term vibration, which will seriously affect the reliability of the entire communication system and thus affect the effectiveness of the online monitoring.

[0004] Some solutions attempt to use wireless communication methods such as WiFi, Bluetooth, or ZigBee. The principles of these technical solutions are mostly based on high-frequency short-range communication protocols, which cannot effectively communicate in the closed strong magnetic environment inside the stator core and suffer from severe signal attenuation. Therefore, they are difficult to meet the stable communication requirements inside the stator core.

[0005] Existing industrial wireless monitoring systems based on LoRa technology mostly adopt a star network topology, where all nodes have a direct communication relationship with the central node gateway. If the central node gateway fails, the monitoring effect of the entire system will be affected, leading to system crashes. Furthermore, within the annular metal structure inside the stator core of hydroelectric generators, some nodes are far from the central node, and there is severe obstruction between nodes, making it difficult to guarantee the stability of the communication link.

[0006] In the prior art, patent CN110400451A provides a vibration and temperature measurement system based on LoRa wireless communication. It adopts a point-to-point / star LoRa communication architecture with a transmitting module and a receiving module. The transmitting end integrates a temperature and vibration sensor, an MCU, and a LoRa transmitting unit, and has digital display, button parameter setting, and local alarm functions. The receiving end receives data through LoRa and uploads it to the control center through a network unit, supporting the MODBUS TCP / IP protocol. It mainly solves the problems of difficult wired wiring and low efficiency of manual inspection in industrial sites, but it lacks specific working condition adaptation design.

[0007] The patent with publication number CN206470931U provides a monitoring device based on LoRa technology, which adopts a standard star topology. The main architecture includes: sensor group → acquisition device → LoRa node → LoRa gateway → data server. The core is to use the low power consumption and long distance characteristics of LoRa to solve the problems of difficult wired construction and short transmission distance of ZigBee.

[0008] However, the existing technology has the following drawbacks:

[0009] All systems employ star / point-to-point networking, rely on a central gateway, and have a single point of failure—if the gateway fails, the entire system will be paralyzed; there are no redundant communication paths, and the signal is severely blocked and attenuated in a metal-enclosed environment, causing communication failure at remote nodes.

[0010] Not designed for strong magnetic fields or enclosed metal ring environments, and lacking an anti-interference adjustment mechanism, the LoRa signal suffers severe attenuation and interference inside the stator core, making stable communication impossible.

[0011] Without fault detection, link redundancy, and topology reconstruction mechanisms, the system directly disconnects after a node / link is interrupted, failing to meet the reliability requirements of long-term unattended operation of hydropower equipment.

[0012] The stator core ring physical structure is not matched, there is no hop-by-hop forwarding mechanism, the single-hop communication distance is too long, the communication quality of remote nodes is extremely poor, and the coverage is insufficient.

[0013] Therefore, current technical solutions are insufficient to achieve low-power, high-reliability, and self-recoverable wireless communication monitoring in complex environments such as strong magnetic fields, strong vibrations, and metal ring enclosures in hydropower unit stators. Summary of the Invention

[0014] To address the above problems, this invention proposes a LoRa wireless communication method for stator core condition monitoring in hydropower units, comprising the following steps: S1. Monitoring nodes are evenly distributed at equal intervals along the circumference of the stator core of the hydropower unit. The nodes include multiple stator core monitoring nodes and at least one convergence node. The physical structure of each node is consistent with the annular structure of the stator core.

[0015] Each monitoring node establishes a communication connection sequentially according to a preset order, with the first and last nodes connected to form a closed ring communication network structure. The aggregation node establishes a communication connection with any monitoring node in the ring communication network structure to receive status monitoring data from the ring network, and finally forwards the monitoring data to the host computer and monitoring backend for centralized data processing.

[0016] The adoption of a ring-shaped communication network structure ensures that the communication path matches the ring-shaped physical structure of the stator core, effectively avoiding the communication obstruction problem of traditional star structures in metal-enclosed environments, and helping to improve overall communication stability and coverage.

[0017] S2. Each monitoring node integrates a sensor module, a microcontroller module, and a LoRa wireless communication module.

[0018] The sensor module is used to collect and monitor the temperature and vibration parameters at key locations of the stator core. The microcontroller module is used to filter, store, encapsulate, and verify the collected status parameter data. The LoRa wireless communication module is used to send and forward status data.

[0019] Each monitoring node is responsible for its own data collection and transmission, and also undertakes the responsibility of relaying data in the ring communication network, relaying data from adjacent nodes, thereby realizing hop-by-hop data transmission between multiple nodes.

[0020] Each monitoring node combines data acquisition and relay forwarding functions, possessing complete communication capabilities. This not only reduces reliance on fixed relay equipment but also improves the flexibility and robustness of node deployment, making it suitable for application scenarios such as stator cores where enclosed spaces and difficult wiring are present.

[0021] S3. The aggregation node broadcasts the network to discover the signal, and each monitoring node measures the signal strength and completes registration. The aggregation node determines the circumferential angle position of the node based on the signal strength, establishes a bidirectional ring connection between the nodes, and generates an initial routing table.

[0022] S4. Calculate the link quality score based on the received signal strength, signal-to-noise ratio, and packet error rate. Count the number of hops in clockwise and counterclockwise directions respectively. Select the direction with fewer hops and better quality as the default primary transmission path, and the other direction as the backup redundant path.

[0023] S5. A hop-by-hop forwarding communication mechanism is used for data transmission. Each monitoring node establishes a communication connection sequentially according to a pre-designed communication order. After the current monitoring node completes data acquisition, it encapsulates the data and sends it to its next neighboring monitoring node. The next monitoring node verifies the data; if the verification passes, it continues to forward the data to the next node, and so on, until it finally converges at the aggregation node.

[0024] S6. An adaptive parameter adjustment mechanism is employed. The system dynamically adjusts the LoRa operating frequency, spreading factor, and transmit power based on real-time communication quality to adapt to the strong magnetic interference environment of the stator core and improve the anti-interference capability of the wireless communication link. When communication quality deteriorates, the system automatically tunes to a low-interference frequency band or increases the spreading factor to enhance anti-interference capability; when communication quality improves, the system appropriately reduces the transmit power or spreading factor to reduce overall power consumption while ensuring normal communication. Through this mechanism, good and stable communication performance can be maintained even in strong electromagnetic environments.

[0025] S7. Each monitoring node periodically sends heartbeat data packets to its neighboring nodes to monitor the communication status. When a node fails multiple heartbeat packet checks, it is determined to be abnormal. Simultaneously, the routing table information of the communication link is updated, the abnormal node is skipped, and the ring communication link is reconstructed to ensure the integrity of the closed communication loop. Through this self-recovery mechanism, the system can still maintain basic communication functions even when a node is missing, and can complete the self-construction of the ring communication network without human intervention. This improves the long-term stability of the overall communication.

[0026] S8. A low-power control and management mechanism is introduced. Each monitoring node automatically enters a deep sleep state during non-communication and non-data acquisition periods. In sleep mode, only essential timers and interrupt modules are retained, while power to other functions is cut off to minimize device power consumption and ensure long-term operation. It wakes up normally during data acquisition and forwarding cycles. This low-power control and management mechanism significantly extends the lifespan of the node's battery-powered modules, facilitating long-term stable monitoring of the stator core status.

[0027] S9. To ensure the reliability and integrity of data transmission, the present invention employs a check code and retransmission mechanism during data transmission to automatically retransmit lost or abnormal data, thereby ensuring the integrity and accuracy of stator core status data.

[0028] Based on the above method, a LoRa wireless communication system for ring network suitable for monitoring the status of stator core of hydropower units is provided, which mainly consists of three parts: a ring monitoring node cluster, a convergence node, and a host computer monitoring backend.

[0029] The ring-shaped monitoring node cluster consists of N homogeneous monitoring nodes arranged at equal intervals along the circumference of the stator core, connected end-to-end to form a closed ring network. Each node has the functions of data acquisition, data forwarding, and link maintenance. It includes the following modules: Sensor module: integrates high-precision temperature sensor and vibration sensor to collect stator core temperature and vibration status parameters in real time; Microcontroller module: performs data filtering, encapsulation, verification, routing calculation, and controls heartbeat transmission and fault diagnosis; LoRa wireless communication module: Supports CN470 frequency band, with bidirectional communication, hop-by-hop forwarding, and adaptive parameter adjustment (frequency point / spreading factor / transmit power) capabilities; Low-power power module: Battery powered, combined with a deep sleep mechanism, to provide long-term stable power supply to the node; Link monitoring module: periodically sends heartbeat packets to monitor the communication status of adjacent nodes and trigger link reconstruction.

[0030] The aggregation node is deployed at any node location in the ring network to bridge the ring network data with the host computer, including: LoRa receiver unit: Communicates with the ring monitoring node to receive monitoring data forwarded hop by hop; Data processing unit: performs data validation, aggregation, and format conversion; Uplink communication unit: forwards the aggregated data to the host computer and monitoring backend.

[0031] The host computer monitoring backend realizes centralized processing and application of monitoring data, including: Data parsing unit: parses monitoring data transmitted through the ring network and extracts parameters such as temperature and vibration; Storage unit: Persistently stores historical monitoring data and network operation logs; Monitoring and display unit: Real-time display of stator core status, network topology, and node communication quality; Early warning unit: When the monitored parameters exceed the standard or there is a network failure, an alarm will be automatically issued.

[0032] Compared with the prior art, the beneficial effects of the present invention include: (1) A closed-loop network is used to replace the traditional star topology, eliminating the need for a central gateway; with bidirectional redundant transmission, the interruption of a single node / link does not affect the communication of the entire network, significantly improving the communication success rate and solving the problem of system paralysis caused by the failure of the central node from the root.

[0033] (2) Equipped with LoRa parameter adaptive adjustment mechanism, it can dynamically adjust frequency point, spreading factor and transmission power, effectively resist strong electromagnetic interference of stator core and metal shielding attenuation, and maintain communication quality under complex and harsh working conditions, solving the problems of signal obstruction and unstable communication in traditional wireless solutions.

[0034] (3) By monitoring the heartbeat, the node status is perceived in real time, faulty nodes are automatically isolated, and adjacent nodes quickly reconstruct the link. The ring network can be self-healed in a short period of time, and the communication loop can be maintained without manual intervention, meeting the requirements of long-term unattended and highly stable operation of hydropower equipment.

[0035] (4) The nodes are arranged at equal intervals along the circumference of the stator core, eliminating the need for large-area wiring and significantly reducing construction difficulty and time; hop-by-hop forwarding breaks down long-distance, high-attenuation communication into short-distance, reliable transmission, fully covering the ring monitoring space, and ensuring uniform communication quality at remote nodes.

[0036] (5) Deep sleep low power management is adopted. During non-working periods, redundant power supplies are cut off and only the core module is powered, which greatly reduces node power consumption, extends battery life, reduces the frequency of on-site maintenance, and is suitable for industrial scenarios with long-term online monitoring.

[0037] (6) Data transmission integrates a verification code and an automatic retransmission mechanism to quickly repair lost / abnormal data, ensuring the integrity and accuracy of monitoring data such as temperature and vibration, and providing reliable data support for the safe operation of hydropower units. Attached Figure Description

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] Figure 1 This is a flowchart of a LoRa wireless communication method for monitoring the stator core condition of a hydroelectric generator, according to the present invention. Detailed Implementation

[0040] The LoRa wireless communication method for stator core condition monitoring of hydropower units, as described in this invention, has the following overall flowchart: Figure 1 As shown, the specific implementation is as follows: Example 1 A LoRa wireless communication method for ring network suitable for monitoring the stator core condition of hydropower units, the method comprising the following steps: S1. Monitoring nodes are evenly distributed at equal intervals along the circumference of the stator core of the hydropower unit. The nodes include multiple stator core monitoring nodes and at least one convergence node. The physical structure of each node is consistent with the annular structure of the stator core.

[0041] Each monitoring node establishes a communication connection sequentially according to a preset order, with the first and last nodes connected to form a closed ring communication network structure. The aggregation node establishes a communication connection with any monitoring node in the ring communication network structure to receive status monitoring data from the ring network, and finally forwards the monitoring data to the host computer and monitoring backend for centralized data processing.

[0042] The adoption of a ring-shaped communication network structure ensures that the communication path matches the ring-shaped physical structure of the stator core, effectively avoiding the communication obstruction problem of traditional star structures in metal-enclosed environments, and helping to improve overall communication stability and coverage.

[0043] S2. Each monitoring node integrates a sensor module, a microcontroller module, and a LoRa wireless communication module.

[0044] The sensor module is used to collect and monitor the temperature and vibration parameters at key locations of the stator core. The microcontroller module is used to filter, store, encapsulate, and verify the collected status parameter data. The LoRa wireless communication module is used to send and forward status data.

[0045] Each monitoring node is responsible for its own data collection and transmission, and also undertakes the responsibility of relaying data in the ring communication network, relaying data from adjacent nodes, thereby realizing hop-by-hop data transmission between multiple nodes.

[0046] Each monitoring node combines data acquisition and relay forwarding functions, possessing complete communication capabilities. This not only reduces reliance on fixed relay equipment but also improves the flexibility and robustness of node deployment, making it suitable for application scenarios such as stator cores where enclosed spaces and difficult wiring are present.

[0047] S3. The aggregation node broadcasts the network to discover the signal, and each monitoring node measures the signal strength and completes registration. The aggregation node determines the circumferential angle position of the node based on the signal strength, establishes a bidirectional ring connection between the nodes, and generates an initial routing table.

[0048] S4. Calculate the link quality score based on the received signal strength, signal-to-noise ratio, and packet error rate. Count the number of hops in clockwise and counterclockwise directions respectively. Select the direction with fewer hops and better quality as the default primary transmission path, and the other direction as the backup redundant path.

[0049] S5. A hop-by-hop forwarding communication mechanism is used for data transmission. Each monitoring node establishes a communication connection sequentially according to a pre-designed communication order. After the current monitoring node completes data acquisition, it encapsulates the data and sends it to its next neighboring monitoring node. The next monitoring node verifies the data; if the verification passes, it continues to forward the data to the next node, and so on, until it finally converges at the aggregation node.

[0050] S6. An adaptive parameter adjustment mechanism is employed. The system dynamically adjusts the LoRa operating frequency, spreading factor, and transmit power based on real-time communication quality to adapt to the strong magnetic interference environment of the stator core and improve the anti-interference capability of the wireless communication link. When communication quality deteriorates, the system automatically tunes to a low-interference frequency band or increases the spreading factor to enhance anti-interference capability; when communication quality improves, the system appropriately reduces the transmit power or spreading factor to reduce overall power consumption while ensuring normal communication. Through this mechanism, good and stable communication performance can be maintained even in strong electromagnetic environments.

[0051] S7. Each monitoring node periodically sends heartbeat data packets to its neighboring nodes to monitor the communication status. When a node fails multiple heartbeat packet checks, it is determined to be abnormal. Simultaneously, the routing table information of the communication link is updated, the abnormal node is skipped, and the ring communication link is reconstructed to ensure the integrity of the closed communication loop. Through this self-recovery mechanism, the system can still maintain basic communication functions even when a node is missing, and can complete the self-construction of the ring communication network without human intervention. This improves the long-term stability of the overall communication.

[0052] S8. A low-power control and management mechanism is introduced. Each monitoring node automatically enters a deep sleep state during non-communication and non-data acquisition periods. In sleep mode, only essential timers and interrupt modules are retained, while power to other functions is cut off to minimize device power consumption and ensure long-term operation. It wakes up normally during data acquisition and forwarding cycles. This low-power control and management mechanism significantly extends the lifespan of the node's battery-powered modules, facilitating long-term stable monitoring of the stator core status.

[0053] S9. To ensure the reliability and integrity of data transmission, the present invention employs a check code and retransmission mechanism during data transmission to automatically retransmit lost or abnormal data, thereby ensuring the integrity and accuracy of stator core status data.

[0054] Example 2 Based on the method described in Embodiment 1, the design of the core steps is provided as follows: (1) Ring network topology design This invention employs a ring network topology that matches the physical structure of the stator core. Let the circumference length of the stator core be L, and the number of monitoring nodes be N. Then, the formula for calculating the node spacing is: ; Among them, d must meet the LoRa communication distance requirements, and it is recommended that d≤50m.

[0055] The nodes are deployed sequentially along the circumference and numbered P1, P2, ..., P n This forms a complete ring communication link: P1→P2→P3→...→P n →P1; The aggregation node G is deployed at any location on the ring and is responsible for communicating with the host computer.

[0056] (2) Sensor configuration Each monitoring node includes a temperature sensor (accuracy ±0.5℃), a vibration sensor (frequency range 0.5-1000Hz), a microcontroller, and a LoRa communication module. The communication module supports the CN470 band, and the transmit power is adjustable from -4dBm to +20dBm.

[0057] (3) Network initialization process Network initialization includes the following steps: A. Aggregation node broadcast network discovers sensors B. Each monitoring node measures the signal strength and registers it with the aggregation node; C. The aggregation node determines the relative position of the nodes based on the signal strength; D. Establish a bidirectional loop connection: Formula for determining node position: ; Where θ is the angular position of node i on the circumference.

[0058] (4) Bidirectional redundant communication mechanism Communication path selection is based on path quality assessment, and the link quality scoring formula is: ; Where α+β+γ=1, RSSI is the received signal strength, SNR is the signal-to-noise ratio, and PER is the packet error rate.

[0059] The path selection algorithm compares the number of hops in clockwise and counterclockwise paths and selects the path with fewer hops as the main communication path.

[0060] Count clockwise: ; Where Hc is the clockwise jump number, i and j are the node IDs, and N is the total number of nodes.

[0061] Counter-clockwise jump count: ; Where Hcc is the counterclockwise jump number, i and j are the node IDs, and N is the total number of nodes.

[0062] (5) Adaptive parameter adjustment mechanism Dynamic frequency selection: When the communication quality Q is lower than the set threshold Q_th, frequency switching is performed. ; Where fnew is the latest frequency and fcurrent is the current frequency. is the frequency step size (200kHz), and k is the switching coefficient based on the interference intensity.

[0063] Power control formula: ; Among them, P min P represents the minimum power. max Q represents maximum power, and Q represents communication quality. maxRepresents the best communication quality.

[0064] Spreading factor selection rules: SF7: When Q > 0.8 and distance d < 20m SF9: When 0.6 < Q ≤ 0.8 or 20m ≤ d < 40m SF12: When Q ≤ 0.6 or d ≥ 40m (6) Hop-by-hop forwarding mechanism The data packet transmission adopts a hierarchical header structure, including routing information, time-to-live TTL, and checksum. The forwarding decision is based on hop count and TTL value to ensure that the data packet is transmitted along the optimal path.

[0065] End-to-end transmission delay calculation formula: ; Where, H is the total number of hops, T_processing is the node processing delay, and T_air is the air transmission delay.

[0066] (7) Heartbeat monitoring and fault recovery The heartbeat packet sending period T_heartbeat = 30 seconds, and the timeout period T_timeout = 90 seconds. Fault detection is based on the reception of heartbeat packets. When no response is received for 3 consecutive heartbeat cycles, the node is determined to be faulty.

[0067] Steps for the ring self-healing protocol execution: A. Establish a direct connection between adjacent nodes of the faulty node; B. Update the global routing table; C. Recalculate the optimal path; D. The network topology convergence time is less than 30 seconds.

[0068] Embodiment III Based on Embodiments I and II, a ring network LoRa wireless communication system applicable to the stator core status monitoring of hydro-generator units is provided, mainly including a ring monitoring node cluster, a convergence node, and a host computer monitoring background.

[0069] The ring monitoring node cluster is composed of N homogeneous monitoring nodes arranged at equal intervals along the circumference of the stator core and connected end to end to form a closed ring network. Each node has the functions of data acquisition, data forwarding, and link maintenance. It includes the following modules: Sensor induction module: Integrates high-precision temperature sensors and vibration sensors to collect stator core temperature and vibration status parameters in real time; Microcontroller module: Completes data filtering, encapsulation, verification, and routing calculation, and controls heartbeat sending and fault determination; LoRa wireless communication module: Supports CN470 frequency band, with bidirectional communication, hop-by-hop forwarding, and adaptive parameter adjustment (frequency point / spreading factor / transmit power) capabilities; Low-power power module: Battery powered, combined with a deep sleep mechanism, to provide long-term stable power supply to the node; Link monitoring module: periodically sends heartbeat packets to monitor the communication status of adjacent nodes and trigger link reconstruction.

[0070] The aggregation node is deployed at any node location in the ring network to bridge the ring network data with the host computer, including: LoRa receiver unit: Communicates with the ring monitoring node to receive monitoring data forwarded hop by hop; Data processing unit: performs data validation, aggregation, and format conversion; Uplink communication unit: forwards the aggregated data to the host computer and monitoring backend.

[0071] The host computer monitoring backend realizes centralized processing and application of monitoring data, including: Data parsing unit: parses monitoring data transmitted through the ring network and extracts parameters such as temperature and vibration; Storage unit: Persistently stores historical monitoring data and network operation logs; Monitoring and display unit: Real-time display of stator core status, network topology, and node communication quality; Early warning unit: When the monitored parameters exceed the standard or there is a network failure, an alarm will be automatically issued.

[0072] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A LoRa wireless communication method using a ring network suitable for monitoring the condition of the stator core of a hydroelectric generator, characterized in that, Includes the following steps: S1. Monitoring nodes and aggregation nodes are arranged at equal intervals along the circumference of the stator core, and connected end to end to form a closed loop communication network; S2. The monitoring node has both data acquisition and relay forwarding functions; S3. The aggregation node broadcasts a discovery signal to complete node registration and generate an initial routing table; S4. Determine the bidirectional primary and backup transmission path based on link quality; S5. Forward monitoring data hop-by-hop; S6. Dynamically adjust LoRa frequency, spreading factor, and transmit power; S7. Heartbeat packets monitor node status and reconstruct faulty links; S8. Enters deep sleep during non-working hours; S9. Data reliability is ensured by using a checksum and retransmission mechanism during transmission.

2. The LoRa wireless communication method for monitoring the stator core condition of hydropower units according to claim 1, characterized in that, The monitoring node in step S2 integrates a temperature sensor, a vibration sensor, a microcontroller, and a LoRa wireless communication module.

3. The LoRa wireless communication method for monitoring the stator core condition of hydropower units according to claim 1, characterized in that, In step S4, the link quality score is calculated based on the received signal strength, signal-to-noise ratio, and packet error rate to select the primary and backup transmission paths.

4. The LoRa wireless communication method for monitoring the stator core condition of hydropower units according to claim 3, characterized in that, The link quality scoring formula is as follows: ； Where α+β+γ=1, RSSI is the received signal strength, SNR is the signal-to-noise ratio, and PER is the packet error rate; The path selection algorithm compares the number of hops in clockwise and counterclockwise paths and selects the path with fewer hops as the main communication path.

5. The LoRa wireless communication method for monitoring the stator core condition of hydropower units according to claim 1, characterized in that, In step S6, when the communication quality deteriorates, the frequency is automatically adjusted to a low-interference frequency band or the spreading factor is increased; when the quality improves, the transmission power or spreading factor is appropriately reduced to reduce overall power consumption. The spreading factor is selected in the following way: SF7 is selected when communication quality Q>0.8 and distance d<20m; SF9 is selected when communication quality Q≤0.8 or distance 20m≤d<40m; and SF12 is selected when communication quality Q≤0.6 or d≥40m.

6. The LoRa wireless communication method for monitoring the stator core condition of hydropower units according to claim 1, characterized in that, In step S7, when a node fails to detect heartbeat packets multiple times during heartbeat monitoring, the node is determined to be abnormal. At the same time, the routing table information of the communication link is updated, the abnormal node is skipped, and the ring communication link is reconstructed.

7. A LoRa wireless communication system for monitoring the stator core condition of a hydroelectric generator, implementing the method as described in any one of claims 1-6, characterized in that, This includes a ring-shaped monitoring node cluster, aggregation nodes, and a host computer monitoring backend; The node cluster is arranged in a closed loop network with equal intervals along the circumference of the stator core, which has the functions of data acquisition, forwarding and link maintenance. The aggregation node receives ring network data and uploads it to the host computer. The host computer performs data parsing, storage, display, and fault warning.

8. The LoRa wireless communication system for monitoring the stator core condition of hydropower units according to claim 7, characterized in that, The monitoring node enters deep sleep during non-working periods, retaining power only for the timer and interrupt module.

9. The LoRa wireless communication system for monitoring the stator core condition of a hydroelectric generator as described in claim 7, characterized in that, The spacing of the monitoring nodes arranged in a circle is adapted to the LoRa communication distance requirements.

10. The LoRa wireless communication system for monitoring the stator core condition of a hydroelectric generator as described in claim 7, characterized in that, The aggregation node can be deployed anywhere in the ring network to complete the data bridging between the ring network and the host computer.

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