A method for on-line monitoring of a surge arrester based on wireless synchronous trigger acquisition

Abstract

The application discloses a lightning arrester online monitoring method based on wireless synchronous trigger collection, belongs to the communication technical field, and comprises a request and preparation stage, independent channel management, trigger package design and sending, sensor synchronous collection, data confirmation and return, solves the technical problem of realizing high-precision wireless synchronous collection of a multi-point lightning arrester online monitoring end, simultaneously guarantees trigger reliability and data consistency, can accurately obtain a leakage current phase and a bus voltage phase, realizes synchronous collection with low time error, greatly reduces collection phase error, fundamentally eliminates time run-time difference and random error between modules, reduces the influence of external interference on triggering, guarantees the real-time performance and accuracy of triggering response, and improves operation safety.

Description

Technical Field

[0001] This invention belongs to the field of communication technology, and in particular relates to an online monitoring method for surge arresters based on wireless synchronous triggering acquisition. Background Technology

[0002] In power systems, existing online surge arrester monitors using capacitive current compensation typically employ a wired approach to achieve data transmission and synchronous sampling between the master and slave devices. Wired synchronization is inconvenient to deploy and suffers from low synchronization accuracy. Long wiring distances result in high costs and extended construction periods, and safety cannot be guaranteed. Wireless time synchronization is also limited by the time deviation caused by individual sensor board offsets, preventing phase synchronization from achieving the desired results.

[0003] The shortcomings of existing technologies are specifically manifested in the following ways: Time synchronization difficulties: Data collected by the MOA leakage current acquisition device and the PT voltage acquisition device at different locations are difficult to align precisely, resulting in large phase analysis errors.

[0004] High interference sensitivity: Fixed frequency points or random wireless channels are easily affected by external wireless interference, reducing trigger reliability.

[0005] Insufficient real-time performance: The acquisition delay is large, and the triggering is disconnected from the data acquisition, making it difficult to meet the needs of rapid fault detection and diagnosis. Summary of the Invention

[0006] The purpose of this invention is to provide an online monitoring method for surge arresters based on wireless synchronous triggering acquisition, which solves the technical problem of achieving high-precision wireless synchronous acquisition at the online monitoring end of multi-point surge arresters while ensuring triggering reliability and data consistency.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A method for online monitoring of surge arresters based on wireless synchronous triggering acquisition includes the following steps: Step 1: The leakage current acquisition device MOA sends an acquisition request to the data acquisition terminal via a wireless network; after the data acquisition terminal confirms the acquisition request, it notifies the PT voltage acquisition device and the leakage current acquisition device MOA to enter standby mode via the wireless network respectively. After entering standby mode, the PT voltage acquisition device and the leakage current acquisition device MOA return their respective ACK commands to the data acquisition terminal. Step 2: The data acquisition terminal maintains an independent channel stack. After receiving two ACK commands from the PT voltage acquisition device and the leakage current acquisition device MOA respectively, the data acquisition terminal sends trigger packets to the PT voltage acquisition device or the leakage current acquisition device MOA through the channels in the independent channel stack. The data acquisition terminal always uses the top channel in the independent channel stack as the pre-selected trigger channel. The stack rules in the independent channel stack for pre-selected trigger channels are as follows: if the top channel is occupied, channels are pushed down in sequence, and the bottom channel is rotated to the top channel position. After a successful trigger, the used channel is pushed to the bottom of the stack to prepare for rotation. At the same time, the channel is only occupied when the trigger packet is sent and is released immediately after the trigger packet is sent. Step 3: The data acquisition terminal selects two pre-selected trigger channels simultaneously according to the method in Step 2, and sends trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA simultaneously using these two pre-selected trigger channels; the trigger packet contains a preamble; after receiving the trigger packet, the PT voltage acquisition device or the leakage current acquisition device MOA generates a trigger command by verifying the preamble. Step 4: After generating the trigger command, the PT voltage acquisition device or leakage current acquisition device MOA first starts the ADC to perform a sampling through a hardware interrupt and stores the real-time data obtained from this sampling into the buffer; then, it performs packet verification on the trigger packet: if the verification is correct, the real-time data of this sampling is retained; if it is incorrect, the real-time data of this sampling is discarded and an error message is generated; based on the packet verification result, the acquisition result is generated, and the timestamp of the received trigger packet is used as the timestamp of the acquisition result and appended to the acquisition result. Step 5: After completing Step 4, the PT voltage acquisition device or the leakage current acquisition device MOA respectively reports their acquisition results to the data acquisition terminal through the public channel. The data acquisition terminal determines whether to initiate re-acquisition based on the acquisition results: if yes, re-acquisition is initiated using the method from Step 1 to Step 4; if no, the consistency of the acquisition results is verified and the acquisition results are saved to the database.

[0008] Preferably, step 1 includes the following steps: Step 1-1: The leakage current acquisition device MOA generates an acquisition request message REQ locally and sends it to the data acquisition terminal through the public channel in the wireless network; The acquisition request message (REQ) includes the request field and the request content (phase acquisition). Step 1-2: After receiving the acquisition request message REQ, the data acquisition terminal parses the confirmation request message REQ and generates an confirmation response ACKreq; the confirmation response ACKreq includes the message field status and the confirmation success flag confirmed; Steps 1-3: The data acquisition terminal simultaneously sends a standby command CMDstandby to the PT voltage acquisition device and the leakage current acquisition device MOA through the public channel, respectively. The standby command CMDstandby includes the command field cmd and the command parameter enter-standby. Steps 1-4: After receiving the standby command CMDstandby, the PT voltage acquisition device or leakage current acquisition device MOA enters standby mode and returns an ACK message to the data acquisition terminal through the public channel. The ACK message includes the acknowledgment field ack and the acknowledgment success status ok.

[0009] Preferably, when performing step 2, the data acquisition terminal generates an independent channel stack during startup initialization and pushes all available channels onto the stack in sequence; After the data acquisition terminal receives two ACK commands simultaneously from the PT voltage acquisition device and the leakage current acquisition device MOA within a preset timeout threshold, it performs an idle check on the top channel of the independent channel stack. If the current top channel of the stack is detected as occupied, then the channel is pushed down and the next channel is detected. At this time, the bottom channel of the stack will be rotated to the position of the top channel of the stack. If the current top channel is idle, then the current top channel is selected as the pre-selected trigger channel; after the data acquisition terminal selects two pre-selected trigger channels at once, it simultaneously sends trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA through these two pre-selected trigger channels respectively; After the data acquisition terminal completes transmission on a pre-selected trigger channel, it immediately releases the pre-selected trigger channel and pushes it to the bottom of the stack.

[0010] Preferably, step 3 includes the following steps: Step 3-1: The data acquisition terminal sends trigger packets to both the PT voltage acquisition device and the leakage current acquisition device MOA simultaneously according to the method in Step 2. The trigger packet includes a preamble, a strong synchronization word SyncWord, a MAC checksum Nonce_MAC, and a frame end flag FrameEnd. Step 3-2: After receiving and buffering the trigger packet, the PT voltage acquisition device or leakage current acquisition device MOA first verifies only the preamble: if correct, a trigger command is generated; otherwise, an error command is generated.

[0011] Preferably, the PT voltage acquisition device or the leakage current acquisition device MOA both cache the trigger packet through their respective local wireless communication modules, verify the preamble, and generate a trigger command or error command.

[0012] Preferably, when performing step 4, the PT voltage acquisition device or the leakage current acquisition device MOA performs the following steps through their respective local wireless communication modules and local MCUs: Step 4-1: After generating a trigger command or an error command, the local wireless communication module determines: if it is a trigger command, proceed to step 4-2; if it is an error command, directly generate a type of error message and proceed to step 5. Step 4-2: The local wireless communication module generates an interrupt signal IRQ at the hardware layer, and this interrupt signal IRQ is input to the local MCU; Step 4-3: After the local MCU detects the interrupt signal IRQ, it enters the interrupt service routine (ISR), and drives the ADC module to start a data acquisition task in the ISR. Step 4-4: After completing a data acquisition task, the local MCU stores the acquired real-time data into the cache; Steps 4-5: The local MCU retrieves the trigger packet from the local wireless communication module and performs a full packet verification on the trigger packet, including verifying the preamble, SyncWord, Nonce_MAC checksum, and FrameEnd flag separately. When the full packet verification is correct, the real-time data is marked as true and prepared to be uploaded to the data acquisition terminal; otherwise, the real-time data is marked as false and two types of error information are generated.

[0013] Preferably, when performing step 5, the PT voltage acquisition device or the leakage current acquisition device MOA respectively executes the following steps through their respective local wireless communication modules and local MCUs: Step 5-1: If there is a type of error message, the local wireless communication module sends that type of error message to the MCU; Step 5-2: The local MCU encapsulates the first type of error information, the second type of error information, or real-time data, generates the acquisition results, and sends them to the local wireless communication module. The local wireless communication module then uploads the acquisition results to the data acquisition terminal through a public channel. Step 5-3: The data acquisition terminal parses the two acquisition results uploaded by the PT voltage acquisition device or the leakage current acquisition device MOA respectively: If both are real-time data, then save both sets of real-time data. If one of them is a Type I or Type II error, return to step 3 and resend the trigger command. If after three resends the two collected results are still not both real-time data, generate an alarm message. Step 5-4: Verify the consistency of the two collection results in time by using the timestamp in the collection results. If the timestamp is less than the preset threshold, store the two collection results in the database; otherwise, mark the collection as a failure, discard the two collection results, and return to step 3 to resend the trigger command.

[0014] This invention discloses an online monitoring method for surge arresters based on wireless synchronous triggering acquisition. It solves the technical problem of achieving high-precision wireless synchronous acquisition of multiple surge arresters in online monitoring while ensuring trigger reliability and data consistency. This invention achieves synchronous acquisition of the surge arrester leakage current and PT-side bus voltage signals through wireless triggering of the data acquisition terminal, thereby accurately obtaining the leakage current phase and bus voltage phase. This method leverages the low latency of wireless signals and the small data interruption consistency error of RF chips. It utilizes the low latency of wireless signals and the data processing consistency of RF modules to achieve synchronous acquisition with low time error. Triggering ADC sampling via a trigger packet ensures that multiple acquisition points begin sampling at the same time, greatly reducing acquisition phase error. It does not rely on remote time synchronization between wireless modules or local crystal oscillator accuracy, eliminating the need for time calibration for each wireless module. Synchronous triggering through the same trigger signal source fundamentally eliminates time discrepancies and random errors between modules. An independent channel stacking rotation strategy dynamically distributes trigger channels, reducing the impact of external interference on triggering. Trigger packet verification and hardware interrupt sampling mechanisms ensure the real-time performance and accuracy of the trigger response. The system automatically generates error messages and alarm mechanisms, improving operational safety. Attached Figure Description

[0015] Figure 1 This is the main flowchart of the present invention; Figure 2 This is a flowchart of step 1 of the present invention; Figure 3 This is a flowchart of step 2 of the present invention; Figure 4 This is a flowchart of step 3 of the present invention; Figure 5 This is a flowchart of step 4 of the present invention; Figure 6 This is a flowchart of step 5 of the present invention; Figure 7 This is a schematic diagram of the system architecture for a minimized application scenario in this embodiment. Detailed Implementation

[0016] Depend on Figures 1-7 The online monitoring method for surge arresters based on wireless synchronous triggering acquisition, as shown, includes the following steps: Step 1: The leakage current acquisition device MOA sends an acquisition request to the data acquisition terminal via a wireless network; after the data acquisition terminal confirms the acquisition request, it notifies the PT voltage acquisition device and the leakage current acquisition device MOA to enter standby mode via the wireless network respectively. After entering standby mode, the PT voltage acquisition device and the leakage current acquisition device MOA return their respective ACK commands to the data acquisition terminal. Step 1 includes the following steps: Step 1-1: The leakage current acquisition device MOA generates an acquisition request message REQ locally and sends it to the data acquisition terminal through the public channel in the wireless network; The acquisition request message (REQ) includes the request field and the request content (phase acquisition). In this embodiment, the request message REQ is ["request": "phase acquisition"]; where "request" indicates the message type and "phase acquisition" indicates a request to acquire phase information.

[0017] Step 1-2: After receiving the acquisition request message REQ, the data acquisition terminal parses the confirmation request message REQ and generates an confirmation response ACKreq; the confirmation response ACKreq includes the message field status and the confirmation success flag confirmed; ACKreq is ["status": "confirmed"]; where "status" indicates the confirmation status and "confirmed" indicates successful confirmation.

[0018] Steps 1-3: The data acquisition terminal simultaneously sends a standby command CMDstandby to the PT voltage acquisition device and the leakage current acquisition device MOA through the public channel, respectively. The standby command CMDstandby includes the command field cmd and the command parameter enter-standby. CMDstandby is defined as ["cmd": "enter-standby"], where "cmd" indicates the command type and "enter-standby" indicates entering standby mode.

[0019] Steps 1-4: After receiving the standby command CMDstandby, the PT voltage acquisition device or leakage current acquisition device MOA enters standby mode and returns an ACK message to the data acquisition terminal through the public channel. The ACK message includes the acknowledgment field ack and the acknowledgment success status ok.

[0020] An ACK message is ["ack": "ok"], where "ack" represents the acknowledgment field and "ok" indicates that the operation was successful.

[0021] Step 2: The data acquisition terminal maintains an independent channel stack. After receiving two ACK commands from the PT voltage acquisition device and the leakage current acquisition device MOA respectively, the data acquisition terminal sends trigger packets to the PT voltage acquisition device or the leakage current acquisition device MOA through the channels in the independent channel stack. The data acquisition terminal always uses the top channel in the independent channel stack as the pre-selected trigger channel. The stack rules in the independent channel stack for pre-selected trigger channels are as follows: if the top channel is occupied, channels are pushed down in sequence, and the bottom channel is rotated to the top channel position. After a successful trigger, the used channel is pushed to the bottom of the stack to prepare for rotation. At the same time, the channel is only occupied when the trigger packet is sent and is released immediately after the trigger packet is sent. When performing step 2, the data acquisition terminal generates an independent channel stack during startup initialization and pushes all available channels onto the stack in sequence; The independent channel stack is as follows: ChannelStack = [CH1, CH2, CH3, ..., CHn], where CH1 is the top of the stack, and CH1, CH2, CH3, ..., CHn are channels. The channels are preset according to the wireless communication channels of the local wireless communication module of the PT voltage acquisition device or the leakage current acquisition device MOA. ChannelStack is an independent channel stack.

[0022] After the data acquisition terminal receives two ACK commands simultaneously from the PT voltage acquisition device and the leakage current acquisition device MOA within a preset timeout threshold, it performs an idle check on the top channel of the independent channel stack. If the current top channel of the stack is detected as occupied, then the channel is pushed down and the next channel is detected. At this time, the bottom channel of the stack will be rotated to the position of the top channel of the stack. If the current top channel of the stack is idle, then select the current top channel of the stack as the pre-selected trigger channel; The independent channel stack is a circular channel stack. When CH1 is pushed down, CHn will replace CH1 to reach the top of the stack and become the new top channel, while other channels are pushed down in turn.

[0023] After selecting two pre-selected trigger channels at once, the data acquisition terminal simultaneously sends trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA through these two pre-selected trigger channels respectively. In this embodiment, the data acquisition terminal sequentially selects two channels as a pair to simultaneously send trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA, thereby minimizing the acquisition time difference between the two devices. When selecting, it is generally assumed that the pre-selected trigger channel of the leakage current acquisition device MOA is selected first, and then the pre-selected trigger channel of the PT voltage acquisition device is selected. For example, if the selected channels are [CH1, CH4], then CH1 is the pre-selected trigger channel of the leakage current acquisition device MOA, and CH4 is the pre-selected trigger channel of the PT voltage acquisition device.

[0024] After the data acquisition terminal completes transmission on a pre-selected trigger channel, it immediately releases the pre-selected trigger channel and pushes it to the bottom of the stack. In this embodiment, releasing the pre-selected trigger channel means marking the pre-selected trigger channel as idle.

[0025] Step 3: The data acquisition terminal selects two pre-selected trigger channels simultaneously according to the method in Step 2, and sends trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA simultaneously using these two pre-selected trigger channels; the trigger packet contains a preamble; after receiving the trigger packet, the PT voltage acquisition device or the leakage current acquisition device MOA generates a trigger command by verifying the preamble. Step 3 includes the following steps: Step 3-1: The data acquisition terminal sends trigger packets to both the PT voltage acquisition device and the leakage current acquisition device MOA simultaneously according to the method in Step 2. The trigger packet includes a preamble, a strong synchronization word SyncWord, a MAC checksum Nonce_MAC, and a frame end flag FrameEnd. In this embodiment, the format of the trigger packet is: TriggerPacket_n={ "Preamble": "0x55AA55AA", / / Preamble, to ensure frame synchronization "SyncWord": "0x55AA", / / Unique identifier for the trigger packet "Nonce_MAC": "0x1F3C", / / Anti-replay / spoofing check "FrameEnd": "0x0D0A" / / Frame end marker } Here, TriggerPacket_n represents the nth trigger packet.

[0026] Step 3-2: After receiving and buffering the trigger packet, the PT voltage acquisition device or leakage current acquisition device MOA first verifies only the preamble: if correct, a trigger command is generated; otherwise, an error command is generated.

[0027] Both the PT voltage acquisition device and the leakage current acquisition device MOA cache the trigger packet through their respective local wireless communication modules, verify the preamble, and generate trigger instructions or error instructions.

[0028] In this embodiment, before the MCU performs verification, the local wireless communication module performs a quick verification. The object of verification is the preamble. If the preamble is correct, it is considered that the conditions for triggering a data acquisition are met, and a trigger command is generated. If there is an error, an error command is generated.

[0029] Step 4: After generating the trigger command, the PT voltage acquisition device or leakage current acquisition device MOA first starts the ADC to perform a sampling through a hardware interrupt and stores the real-time data obtained from this sampling into the buffer; then, it performs packet verification on the trigger packet: if the verification is correct, the real-time data of this sampling is retained; if it is incorrect, the real-time data of this sampling is discarded and an error message is generated; based on the packet verification result, the acquisition result is generated, and the timestamp of the received trigger packet is used as the timestamp of the acquisition result and appended to the acquisition result. In this embodiment, the PT voltage acquisition device or the leakage current acquisition device MOA includes two units: a local ADC conversion unit and a local wireless communication module. The local ADC conversion unit includes a local MCU and a local ADC. The local MCU and the local ADC are connected through an I / O port. The local wireless communication module includes a local wireless communication chip and a local FPGA chip. The local wireless communication chip is connected to the local FPGA chip. The local FPGA chip is connected to and communicates with the local MCU. The FPGA chip generates an interrupt signal IRQ through an I / O port. The interrupt signal IRQ is connected to an interrupt of the local MCU. After the local MCU detects the interrupt signal IRQ, it enters the interrupt service routine (ISR) and performs a data acquisition task.

[0030] like Figure 7 The figure shows a minimized application scenario of the present invention, wherein the PT voltage acquisition device includes at least MCU1, ADC1, wireless communication chip IC1 and FPGA1, both of which are connected to MCU1, and wireless communication chip IC1 is connected to FPGA1. The leakage current acquisition device MOA includes at least MCU2, ADC2, wireless communication chip IC2 and FPGA2. Both ADC2 and FPGA2 are connected to MCU2, and wireless communication chip IC2 is connected to FPGA2.

[0031] In this embodiment, the MCU is an STM32H743ZIT6, the ADC is an ADS1278IPAPT, the wireless communication chip is an SX1280IMLTRT, and the FPGA is a Xilinx Artix-7 XC7A35T. The leakage current acquisition device (MOA) and the PT voltage acquisition device are existing products and will not be described in detail.

[0032] When performing step 4, the PT voltage acquisition device or leakage current acquisition device MOA performs the following steps through their respective local wireless communication modules and local MCUs: Step 4-1: After generating a trigger command or an error command, the local wireless communication module determines: if it is a trigger command, proceed to step 4-2; if it is an error command, directly generate a type of error message and proceed to step 5. Step 4-2: The local wireless communication module generates an interrupt signal IRQ at the hardware layer, and this interrupt signal IRQ is input to the local MCU; Step 4-3: After the local MCU detects the interrupt signal IRQ, it enters the interrupt service routine (ISR), and drives the ADC module to start a data acquisition task in the ISR. Step 4-4: After completing a data acquisition task, the local MCU stores the acquired real-time data into the cache; Steps 4-5: The local MCU retrieves the trigger packet from the local wireless communication module and performs a full packet verification on the trigger packet, including verifying the preamble, SyncWord, Nonce_MAC checksum, and FrameEnd flag separately. When the full packet verification is correct, the real-time data is marked as true and prepared to be uploaded to the data acquisition terminal; otherwise, the real-time data is marked as false and two types of error information are generated.

[0033] Step 5: After completing Step 4, the PT voltage acquisition device or the leakage current acquisition device MOA respectively reports their acquisition results to the data acquisition terminal through the public channel. The data acquisition terminal determines whether to initiate re-acquisition based on the acquisition results: if yes, re-acquisition is initiated using the method from Step 1 to Step 4; if no, the consistency of the acquisition results is verified and the acquisition results are saved to the database.

[0034] When performing step 5, the PT voltage acquisition device or the leakage current acquisition device MOA respectively executes the following steps through their local wireless communication module and local MCU: Step 5-1: If there is a type of error message, the local wireless communication module sends that type of error message to the MCU; Step 5-2: The local MCU encapsulates the first type of error information, the second type of error information, or real-time data, generates the acquisition results, and sends them to the local wireless communication module. The local wireless communication module then uploads the acquisition results to the data acquisition terminal through a public channel. In this embodiment, the acquisition results are encapsulated as follows: ResultPacket = { "timestamp": "20XX-XX-XXTXX:XX:XXZ", "DataValid": True, "Data": [data...], / / ADC acquisition data "ErrorType": null } In this context, ResultPacket represents the collected results, timestamp represents the timestamp, DataValid represents the data validity, Data represents the specific data collected, ErrorType represents the error type, null indicates no error, and Error_0x0020 represents a Type II error.

[0035] Step 5-3: The data acquisition terminal parses the two acquisition results uploaded by the PT voltage acquisition device or the leakage current acquisition device MOA respectively: If both are real-time data, then save both sets of real-time data. If one of them is a Type I or Type II error, return to step 3 and resend the trigger command. If after three resends the two collected results are still not both real-time data, generate an alarm message. Step 5-4: Verify the consistency of the two collection results in time by using the timestamp in the collection results. If the timestamp is less than the preset threshold, store the two collection results in the database; otherwise, mark the collection as a failure, discard the two collection results, and return to step 3 to resend the trigger command.

[0036] This invention discloses an online monitoring method for surge arresters based on wireless synchronous triggering acquisition. It solves the technical problem of achieving high-precision wireless synchronous acquisition of multiple surge arresters in online monitoring while ensuring trigger reliability and data consistency. This invention achieves synchronous acquisition of the surge arrester leakage current and PT-side bus voltage signals through wireless triggering of the data acquisition terminal, thereby accurately obtaining the leakage current phase and bus voltage phase. This method leverages the low latency of wireless signals and the small data interruption consistency error of RF chips. It utilizes the low latency of wireless signals and the data processing consistency of RF modules to achieve synchronous acquisition with low time error. Triggering ADC sampling via a trigger packet ensures that multiple acquisition points begin sampling at the same time, greatly reducing acquisition phase error. It does not rely on remote time synchronization between wireless modules or local crystal oscillator accuracy, eliminating the need for time calibration for each wireless module. Synchronous triggering through the same trigger signal source fundamentally eliminates time discrepancies and random errors between modules. An independent channel stacking rotation strategy dynamically distributes trigger channels, reducing the impact of external interference on triggering. Trigger packet verification and hardware interrupt sampling mechanisms ensure the real-time performance and accuracy of the trigger response. The system automatically generates error messages and alarm mechanisms, improving operational safety.

Claims

1. A method for online monitoring of surge arresters based on wireless synchronous triggering acquisition, characterized in that: Includes the following steps: Step 1: The leakage current acquisition device MOA sends an acquisition request to the data acquisition terminal via a wireless network; after the data acquisition terminal confirms the acquisition request, it notifies the PT voltage acquisition device and the leakage current acquisition device MOA to enter standby mode via the wireless network respectively. After entering standby mode, the PT voltage acquisition device and the leakage current acquisition device MOA return their respective ACK commands to the data acquisition terminal. Step 2: The data acquisition terminal maintains an independent channel stack. After receiving two ACK commands from the PT voltage acquisition device and the leakage current acquisition device MOA respectively, the data acquisition terminal sends trigger packets to the PT voltage acquisition device or the leakage current acquisition device MOA through the channels in the independent channel stack. The data acquisition terminal always uses the top channel in the independent channel stack as the pre-selected trigger channel. The stack rules in the independent channel stack for pre-selected trigger channels are as follows: if the top channel is occupied, channels are pushed down in sequence, and the bottom channel is rotated to the top channel position. After a successful trigger, the used channel is pushed to the bottom of the stack to prepare for rotation. At the same time, the channel is only occupied when the trigger packet is sent and is released immediately after the trigger packet is sent. When performing step 2, the data acquisition terminal generates an independent channel stack during startup initialization and pushes all available channels onto the stack in sequence; After the data acquisition terminal receives two ACK commands simultaneously from the PT voltage acquisition device and the leakage current acquisition device MOA within a preset timeout threshold, it performs an idle check on the top channel of the independent channel stack. If the current top channel of the stack is detected as occupied, then the channel is pushed down and the next channel is detected. At this time, the bottom channel of the stack will be rotated to the position of the top channel of the stack. If the current top channel of the stack is idle, then the current top channel of the stack is selected as the pre-selected trigger channel; after the data acquisition terminal selects two pre-selected trigger channels at a time, it simultaneously sends trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA through these two pre-selected trigger channels respectively; After the data acquisition terminal completes transmission on a pre-selected trigger channel, it immediately releases the pre-selected trigger channel and pushes it to the bottom of the stack. Step 3: The data acquisition terminal selects two pre-selected trigger channels simultaneously according to the method in Step 2, and sends trigger packets to the PT voltage acquisition device and the leakage current acquisition device MOA simultaneously using these two pre-selected trigger channels; the trigger packet contains a preamble; after receiving the trigger packet, the PT voltage acquisition device or the leakage current acquisition device MOA generates a trigger command by verifying the preamble. Step 4: After generating the trigger command, the PT voltage acquisition device or leakage current acquisition device MOA first starts the ADC to perform a sampling through hardware interrupt and stores the real-time data obtained from this sampling into the buffer; then it performs packet verification on the trigger packet: if the verification is correct, the real-time data of this sampling is retained. If incorrect, discard the real-time data from this sampling and generate an error message; Based on the packet verification result, generate the collection result and append the timestamp of the received trigger packet as the timestamp of the collection result to the collection result; When performing step 4, the PT voltage acquisition device or leakage current acquisition device MOA performs the following steps through their respective local wireless communication modules and local MCUs: Step 4-1: After generating a trigger command or an error command, the local wireless communication module determines: if it is a trigger command, proceed to step 4-2; if it is an error command, directly generate a type of error message and proceed to step 5. Step 4-2: The local wireless communication module generates an interrupt signal IRQ at the hardware layer, and this interrupt signal IRQ is input to the local MCU; Step 4-3: After the local MCU detects the interrupt signal IRQ, it enters the interrupt service routine (ISR), and drives the ADC module to start a data acquisition task in the ISR. Step 4-4: After completing a data acquisition task, the local MCU stores the acquired real-time data into the cache; Steps 4-5: The local MCU retrieves the trigger packet from the local wireless communication module and performs a full packet verification on the trigger packet, including verifying the preamble, SyncWord, Nonce_MAC checksum, and FrameEnd flag separately. When the full packet verification is correct, the real-time data is marked as true and prepared to be uploaded to the data acquisition terminal; otherwise, the real-time data is marked as false and two types of error messages are generated. Step 5: After completing Step 4, the PT voltage acquisition device or the leakage current acquisition device MOA respectively reports their acquisition results to the data acquisition terminal through the public channel. The data acquisition terminal determines whether to initiate re-acquisition based on the acquisition results: if yes, re-acquisition is initiated using the methods in Steps 1 to 4; if no, the consistency of the acquisition results is verified and the acquisition results are saved to the database.

2. The online monitoring method for surge arresters based on wireless synchronous triggering acquisition as described in claim 1, characterized in that: Step 1 includes the following steps: Step 1-1: The leakage current acquisition device MOA generates an acquisition request message REQ locally and sends it to the data acquisition terminal through the public channel in the wireless network; The acquisition request message (REQ) includes the request field and the request content (phase acquisition). Step 1-2: After receiving the acquisition request message REQ, the data acquisition terminal parses the confirmation request message REQ and generates an confirmation response ACKreq; the confirmation response ACKreq includes the message field status and the confirmation success flag confirmed; Steps 1-3: The data acquisition terminal simultaneously sends a standby command CMDstandby to the PT voltage acquisition device and the leakage current acquisition device MOA through the public channel, respectively. The standby command CMDstandby includes the command field cmd and the command parameter enter-standby. Steps 1-4: After receiving the standby command CMDstandby, the PT voltage acquisition device or leakage current acquisition device MOA enters standby mode and returns an ACK message to the data acquisition terminal through the public channel. The ACK message includes the acknowledgment field ack and the acknowledgment success status ok.

3. The online monitoring method for surge arresters based on wireless synchronous triggering acquisition as described in claim 1, characterized in that: Step 3 includes the following steps: Step 3-1: The data acquisition terminal sends trigger packets to both the PT voltage acquisition device and the leakage current acquisition device MOA simultaneously according to the method in Step 2. The trigger packet includes a preamble, a strong synchronization word SyncWord, a MAC checksum Nonce_MAC, and a frame end flag FrameEnd. Step 3-2: After receiving and buffering the trigger packet, the PT voltage acquisition device or leakage current acquisition device MOA first verifies only the preamble: if correct, a trigger command is generated; otherwise, an error command is generated.

4. The online monitoring method for surge arresters based on wireless synchronous triggering acquisition as described in claim 3, characterized in that: Both the PT voltage acquisition device and the leakage current acquisition device MOA cache the trigger packet through their respective local wireless communication modules, verify the preamble, and generate trigger instructions or error instructions.

5. The online monitoring method for surge arresters based on wireless synchronous triggering acquisition as described in claim 4, characterized in that: When performing step 5, the PT voltage acquisition device or the leakage current acquisition device MOA respectively executes the following steps through their local wireless communication module and local MCU: Step 5-1: If there is a type of error message, the local wireless communication module sends that type of error message to the MCU; Step 5-2: The local MCU encapsulates the first type of error information, the second type of error information, or real-time data, generates the acquisition results, and sends them to the local wireless communication module. The local wireless communication module then uploads the acquisition results to the data acquisition terminal through a public channel. Step 5-3: The data acquisition terminal parses the two acquisition results uploaded by the PT voltage acquisition device or the leakage current acquisition device MOA respectively: If both are real-time data, then save both sets of real-time data. If one of them is a Type I or Type II error, return to step 3 and resend the trigger command. If after three resends the two collected results are still not both real-time data, generate an alarm message. Step 5-4: Verify the consistency of the two collection results in time by using the timestamps in the collection results. If the timestamps are less than the preset threshold, store the two collection results in the database. Conversely, if the data collection fails, the data collection is marked as a failure, both data collection results are discarded, and the process returns to step 3 to resend the trigger command.

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