A data acquisition system and method for aviation power distribution center based on CAN bus networking

Abstract

This invention discloses a data acquisition system and method for an aviation power distribution center based on a CAN bus network. The system's data acquisition unit is configured as the master node of the CAN bus network, and each device within the aviation power distribution center with data transmission needs is configured as a sub-node of the CAN bus network. All devices within the aviation power distribution center with data transmission needs are connected to a remote interface unit 2 via a bus. The data acquisition unit includes: a processor chip with at least two eCAN interfaces, a CAN transceiver connected to each eCAN interface, and a first and second communication transceiver. All devices within the aviation power distribution center with data transmission needs are connected to at least two CAN transceivers in the data acquisition unit via at least two CAN buses. In the data acquisition system, all devices within the aviation power distribution center with data transmission needs send operational data information to the remote interface unit 2 via the bus, and transmit all operational data information of all devices to the data acquisition unit via at least two CAN buses, so that the data acquisition unit can send it to the remote interface unit 1 via the first communication transceiver. Furthermore, during ground maintenance, the operational data information of each device within the power distribution center recorded by the data acquisition unit is downloaded to ground maintenance equipment.

Description

Technical Field

[0001] This invention relates to, but is not limited to, the field of aviation power distribution technology, and particularly to a data acquisition system and method for an aviation power distribution center based on CAN bus networking. Background Technology

[0002] The aviation power distribution center is a crucial component of the aircraft's power supply system. Its main functions include supplying, controlling, converting, and monitoring the 270V DC, 28V DC, and 115V AC power in the aircraft, and providing power to high-power electrical equipment, primary electrical equipment, and remote secondary power distribution devices. The aviation power distribution center ensures the power supply to critical aircraft equipment, guaranteeing the safety of aircraft operations; therefore, it holds a pivotal position.

[0003] Currently, conventional power distribution centers mainly consist of power control and protection devices such as contactors, circuit breakers, and diodes, as well as equipment such as contactor control units and power control units. Real-time operational status information within the power distribution center is collected, monitored, and stored by these devices, and the operational results are reported to the RIU (Remote Interface Unit) via the HB6096 bus. With the increasing types and numbers of aircraft electrical equipment, and the growing trend towards more-electric and all-electric aircraft, aircraft power supply systems are becoming increasingly complex. The number of devices within the power distribution center is also increasing. Limited by the number of communication interfaces between the HB6096 bus and the RIU, simply adding more RIU communication interfaces to ensure the transmission of operational data within the power distribution center would not only increase the weight and size of the aircraft power supply system but also complicate its control and communication networks. This would negatively impact overall flight safety, performance, manufacturing costs, and operating costs, ultimately reducing the reliability of aircraft operation. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned technical problems. This invention provides a data acquisition system and method for an aviation power distribution center based on a CAN bus network. This addresses the issue that existing methods of increasing the number of devices in an aviation power distribution center by adding RIU communication interfaces to ensure the transmission of operational data not only increase the weight and volume of the aircraft power supply system but also complicate its control and communication networks. This negatively impacts overall flight safety, performance, manufacturing costs, and operating costs, ultimately reducing the reliability of aircraft operations.

[0005] The technical solution of the present invention: In a first aspect, the embodiments of the present invention provide a data acquisition system for an aviation power distribution center based on CAN bus networking, including: all devices in the aviation power distribution center that have data transmission requirements, and a data acquisition unit;

[0006] The data acquisition unit is configured as the master node of the CAN bus network, and each device in the aviation power distribution center with data transmission requirements is configured as a sub-node of the CAN bus network. All devices in the aviation power distribution center with data transmission requirements are connected to the remote interface unit 2 via the bus.

[0007] The data acquisition unit includes: a processor chip with at least two eCAN interfaces, a CAN transceiver connected to each eCAN interface, and a first communication transceiver and a second communication transceiver; all equipment in the aviation power distribution center with data transmission requirements is connected to at least two CAN transceivers in the data acquisition unit through at least two CAN buses, the output interface of the processor chip is connected to the remote interface unit 1 through the first communication transceiver, and the other output interface of the processor chip is connected to the ground maintenance equipment through the second communication transceiver;

[0008] In the data acquisition system, all devices in the aviation power distribution center that have data transmission requirements send operating data information to the remote interface unit 2 via a bus, and transmit the operating data information of all devices to the data acquisition unit via at least two CAN buses, so that the data acquisition unit can send it to the remote interface unit 1 via the first communication transceiver; and during ground maintenance, the operating data information of each device in the power distribution center recorded by the data acquisition unit is downloaded to the ground maintenance equipment.

[0009] Optionally, in the data acquisition system of the aviation power distribution center based on CAN bus networking as described above, each device in the aviation power distribution center with data transmission requirements has one HB6096 bus, one RS422 bus interface, and one CAN bus interface. Each device is connected to the remote interface unit 2 through one HB6096 bus interface. Some devices are connected to the data acquisition unit as the communication master node through the first CAN bus as communication sub-nodes, and other devices are connected to the data acquisition unit as the communication master node through the second CAN bus sub-node.

[0010] Under normal operating conditions, each device periodically uploads its own operating data information to the remote interface unit 2 through its respective HB6096 bus interface;

[0011] After each device receives a command from the data acquisition unit via the CAN bus interface, it feeds back the relevant operating data information to the data acquisition unit via the corresponding CAN bus.

[0012] During ground maintenance, the ground maintenance equipment downloads the data stored in each device via the RS422 bus interface.

[0013] Optionally, in the data acquisition system of the aviation power distribution center based on CAN bus networking as described above, the data acquisition unit has 2 CAN communication interfaces, 1 RS422 communication interface and 1 HB6096 bus interface; the first CAN communication interface is connected to the CAN bus interface of the aforementioned equipment in a bus topology; the second CAN communication interface is connected to the CAN bus interface of the other equipment in a bus topology.

[0014] The data acquisition unit is used to acquire the operating data information of each device in the power distribution center from the first CAN communication interface and the second CAN communication interface under normal operating conditions. Then, its internal processor chip converts the data into the HB6096 communication data format and reports it to the remote interface unit 1 through the HB6096 bus interface. It is also used to download the operating data information of each device in the power distribution center recorded by the data acquisition unit through the RS422 bus interface when performing ground maintenance.

[0015] Secondly, embodiments of the present invention also provide a data acquisition method for an aviation power distribution center based on a CAN bus network. The method employs a data acquisition system for an aviation power distribution center based on a CAN bus network as described above to perform data acquisition on the aviation power distribution center. The power distribution center is configured to have 32 devices, and the processor chip of the data acquisition device is externally connected to NVSRAM and FLASH. The method includes:

[0016] Step 1: Set the CAN communication task completion flag to invalid, set the CAN communication task count range to 0-32, and the task count interval to 2ms; when the CAN communication task completion flag is invalid, the data acquisition unit acquires the operating data information of each device in the power distribution center through the first CAN bus and the second CAN bus at a period of 2ms.

[0017] Step 2: When the CAN communication task completion flag is valid, set the HB6096 communication task count range to 0-5 and the task count interval to 14ms. When the HB6096 communication task completion flag is invalid, the data acquisition unit will convert the operating data of each device in the power distribution center collected through CAN communication into HB6096 communication format. Every 14ms, the data will be reported to the remote interface unit 1 through the HB6096 communication interface and stored in the NVSRAM connected to the processor chip through the data bus. When the HB6096 communication task count reaches 5, the HB6096 communication completion flag will be set to valid.

[0018] Step 3: When the HB6096 communication completion flag is valid and the 350ms task cycle flag is valid, set the FLASH storage flag to valid, and read out the data stored in the NVSRAM within the last two HB6096 communication cycles and transfer it sequentially to the FLASH external to the processor chip. After storage is completed, set the FLASH storage flag to invalid and clear the 350ms task cycle flag to invalid.

[0019] Step 4: If the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid, determine whether FLASH erasure is required based on the current tail pointer of FLASH storage. If erasure is required, then FLASH erasure is performed.

[0020] Optionally, in the data acquisition method of the aviation power distribution center based on CAN bus networking as described above, the data acquisition device uses NVSRAM to record data when the system malfunctions, and uses FLASH to periodically record system monitoring data, and both use a cyclic overwrite storage method.

[0021] The NVSRAM is divided into three areas: Area 1 is used to store the NVSRAM fault record tail pointer, FLASH record tail pointer, monitoring backup data head pointer, and tail pointer; Area 2 is used to cyclically store system fault data; Area 3 is used to store monitoring backup data; and Area 3 is used to store the monitoring backup data within the 400ms period.

[0022] Optionally, in the data acquisition method for an aviation power distribution center based on CAN bus networking as described above, the method further includes:

[0023] Every 2ms, check if the data acquisition system has failed. If a failure occurs, store the fault data in bytes in area 2 of NVSRAM.

[0024] Optionally, in the data acquisition method for an aviation power distribution center based on CAN bus networking as described above,

[0025] In step 2, during the execution of the HB6096 communication task, after each 32×32-bit communication data packet is sent to the HB6096 communication interface, the data packet is stored in area 3 of the NVSRAM. The specific storage method includes:

[0026] Step 21: Update the 32nd bit of the 32-bit data in the HB6096 communication format. The update method is as follows: sum the data bits of the HB6096 communication, i.e., bits 11 to 29. If the sum is even, set bit 32 to 1; if the sum is odd, clear bit 32 to 0.

[0027] Step 22: After the data content is updated, the 32×32-bit communication data of the packet is transferred to the cache array;

[0028] Step 23: If the task cycle flag for the previous 200ms is valid, perform the following operations:

[0029] S23a, Read the tail pointer of the monitoring backup data from area 1 of NVSRAM and perform segment swapping on the tail pointer of the monitoring backup data;

[0030] S23b, store the updated monitoring backup data tail pointer as the monitoring backup data head pointer in NVSRAM area 1;

[0031] S23c, stores the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address, and after storage is completed, stores the updated monitoring backup data tail pointer into NVSRAM area 1;

[0032] Step 24: If the task cycle flag for the previous 200ms is invalid, perform the following operations:

[0033] S24a, Read the tail pointer of the monitoring backup data from NVSRAM area 1 and perform segment swapping on the tail pointer of the monitoring backup data;

[0034] S24b: Store the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address. After storage, store the updated monitoring backup data tail pointer into NVSRAM area 1.

[0035] Optionally, in the data acquisition method for an aviation power distribution center based on CAN bus networking as described above, the method for performing segment switching on the tail pointer is as follows:

[0036] The maximum address in NVSRAM region 3 is compared with the monitoring backup data tail pointer. If the difference is less than 32×32 bits, the monitoring backup data tail pointer is set to the initial address value of the monitoring backup data tail pointer, and the updated monitoring backup data tail pointer is stored in NVSRAM region 1.

[0037] Optionally, in the data acquisition method for an aviation power distribution center based on CAN bus networking as described above, in step 3, when the data acquisition unit performs a 350ms cycle task, if the FLASH storage flag is valid, it transfers one page of data from NVSRAM to FLASH every 2ms, repeating this process 6 times consecutively; the storage method includes:

[0038] Step 31: Read the FLASH record tail pointer and monitoring backup data head pointer in NVSRAM area 1;

[0039] Step 32, perform segment switching based on the FLASH record tail pointer: compare the maximum address of FLASH storage with the FLASH record tail pointer. If the difference is less than or equal to Δ1, set the FLASH record tail pointer to the initial address value of the FLASH record tail pointer and store the updated FLASH record tail pointer in NVSRAM area 1. Otherwise, no processing is performed. Here, Δ1 is 256 bytes.

[0040] Step 33: Read 256 bytes of data sequentially from NVSRAM area 3, starting from the monitoring backup data header pointer, and then store them sequentially into the FLASH memory starting from the FLASH record tail pointer; after storage, store the updated FLASH record tail pointer into NVSRAM area 1.

[0041] Step 34: Increment the FLASH task count by 1; if the FLASH task count is greater than or equal to 6, clear the FLASH task count to 0 and set the FLASH storage flag to invalid and the 350ms task cycle flag to invalid; otherwise, do not process.

[0042] Optionally, in the data acquisition method for an aviation power distribution center based on CAN bus networking as described above, the erasure time of the FLASH used in step 4 is 300ms. When the data acquisition device determines that the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid, it executes the FLASH erasure task. Specific implementation methods include:

[0043] Step 41: Read the FLASH record tail pointer from NVSRAM area 1;

[0044] Step 42: Calculate the sector where the current FLASH record tail pointer is located based on the FLASH record tail pointer;

[0045] Step 43: Compare the maximum address of the current sector with the FLASH record tail pointer. If the difference is less than or equal to Δ2, then set the erase flag to valid; otherwise, set the erase flag to invalid. Here, Δ2 is 1536 bytes.

[0046] Step 44: If the erase flag is valid, and the sector where the current FLASH record tail pointer is located is the sector with the maximum number of times FLASH can be used, then set the FLASH erase address to the initial address value of the FLASH record tail pointer; if the sector where the current FLASH record tail pointer is located is smaller than the sector with the maximum number of times FLASH can be used, then set the FLASH erase address to the starting address of the next sector; otherwise, do not process it.

[0047] Step 45: FLASH performs sector erasure according to the FLASH erase address.

[0048] The beneficial effects of this invention are as follows: Addressing the issue of communication or data storage anomalies in aviation power distribution centers caused by the complex electromagnetic and natural environment on board during aircraft flight, this invention provides a data acquisition system and method for aviation power distribution centers based on a CAN bus network to meet the redundancy design requirements for onboard communication and storage. Specifically, it proposes using a CAN bus-based data acquisition system for aviation power distribution centers as a data redundancy design, fully utilizing the high reliability and security, simple topology, and good transmission distance and speed advantages of the CAN bus's cyclic redundancy check (CRC) function. The aviation power distribution center provides operational data information to remote interface unit 1 and remote interface unit 2. On one hand, each device in the power distribution center uploads communication data to remote interface unit 2 and receives instructions from remote interface unit 2 via the HB6096 bus interface; on the other hand, the data acquisition system based on the CAN bus network acquires operational data from multiple devices in the power distribution center with data transmission needs, and then transmits this data to remote interface unit 1 via the HB6096 bus interface.

[0049] Furthermore, to fully consider the weight and size of the designed data acquisition system, the system leverages the advantages of NVSRAM (small capacity but fast byte-by-byte access) and FLASH (large capacity but requires erasure before access). Both NVSRAM and FLASH are used. Fault data is stored in NVSRAM to ensure speed and timeliness; backup monitoring data is stored in NVSRAM and periodically transferred to FLASH, avoiding reliability issues during FLASH erasure. This provides strong assurance for the reliability of communication and data storage in aircraft flight, and is of great significance in the aviation and aerospace fields. Attached Figure Description

[0050] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0051] Figure 1A schematic diagram of the structure of a data acquisition system for an aviation power distribution center based on CAN bus networking, provided for an embodiment of the present invention;

[0052] Figure 2 A flowchart illustrating a data acquisition method for an aviation power distribution center based on CAN bus networking, provided in an embodiment of the present invention. Detailed Implementation

[0053] To make the purpose, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other in any manner.

[0054] As explained in the background section, the power distribution center plays a crucial role in the aircraft power supply system. With the increasing types and quantities of aircraft electrical equipment, the number of communication interfaces via the HB6096 bus and the RIU (Integrated Equipment Unit) remains a constraint. Simply increasing the number of RIU communication interfaces to ensure the transmission of operational data in the power distribution center would not only increase the weight and size of the aircraft power supply system but also complicate its control and communication networks. This would negatively impact overall flight safety, performance, manufacturing costs, and operating costs, ultimately reducing the reliability of aircraft operations.

[0055] To address the aforementioned issues, this embodiment of the invention considers using a communication network to collect data information within the power distribution center via a high-speed bus, convert it into HB6096 communication format, and report it to the RIU.

[0056] Generally, high-speed buses used for aviation communication networking include RS485 bus, CAN bus, and 1553B bus. Among them, RS485 bus is a half-duplex asynchronous serial communication, which generally supports a maximum of 32 nodes on the same bus, with a maximum distance of 1200 meters and a maximum transmission rate of 10Mb / s. However, the maximum transmission rate of a 100-meter twisted pair cable is 1Mb / s. It is a single-master network with no fault tolerance mechanism, and a single node error can easily affect the entire communication network. Therefore, it is not suitable for complex communication networks with multiple child nodes. 1553B bus is also a half-duplex asynchronous serial communication, which generally supports a maximum of 31 nodes on the same bus. It has a fault tolerance mechanism, but the maximum distance is only 6.1m. The distance between child nodes in the communication network is a significant challenge, and its cost and maintenance costs are relatively high. CAN communication, on the other hand, has the flexibility of multi-master-multi-slave or one-master-multi-slave, a maximum transmission rate of 1Mb / s on a 40-meter twisted pair cable, and supports a maximum of 110 nodes on the same bus. It has higher fault tolerance and reliability, and its cost, development difficulty, and maintenance difficulty are all advantages. Therefore, it is more suitable for aviation power distribution centers with multiple communication nodes.

[0057] The patent "A Vehicle Data Acquisition and Analysis System Based on CAN Bus" (patent number CN202311414500.5) proposes a vehicle data acquisition and analysis system based on CAN bus. This system acquires vehicle status monitoring data from buses via CAN bus and evaluates the recorded vehicle operating status data through modules such as status fluctuation analysis, baseline determination, and condition judgment, providing early warnings for abnormal parameters. This patent is primarily used for monitoring and evaluating status data in the field of vehicle control and can achieve safety analysis. However, it does not specify the detailed implementation method of the CAN bus system during the acquisition process, making it impossible to guarantee whether this method can be applied to complex aviation power distribution centers with multiple sub-nodes.

[0058] The patent "CAN Data Acquisition and Transmission Method, Device and Vehicle Terminal" (patent number CN113872840A) proposes a CAN data acquisition and transmission method, device and vehicle terminal suitable for automobiles, detailing the steps of the CAN data acquisition and transmission method. However, it only has 3 nodes on its bus. Since the CAN bus is a half-duplex communication mode, it cannot guarantee whether this method can be applied to complex aviation power distribution centers with multiple sub-nodes.

[0059] The patent "A Distributed Multi-Channel Data Acquisition System Based on CAN Bus Technology" (patent number CN205263583U) proposes a distributed data acquisition system. It implements data transfer via a CAN-to-RS422 interface, and the transfer unit is connected to an external FLASH memory to cyclically store and back up the acquired data, facilitating later fault tracing. However, since this patent mainly describes the bus architecture, it does not provide detailed implementation methods for communication between the various sub-nodes.

[0060] The patent "An ECU Data Acquisition Device Based on CAN Bus" (patent number CN210835674U) proposes to read the device operation data on the CAN bus network, convert it into an RS232 interface, and transfer it to an SD card through the control unit. This method is simple and effective for large-capacity data acquisition, but it does not provide detailed implementation methods for communication between sub-nodes.

[0061] The patent "A Data Acquisition System Based on CAN Bus" (patent number CN214474538U) proposes a data acquisition system for vehicle power distribution technology. This patent mainly describes the main hardware design of the system, but does not provide detailed implementation methods for communication between each sub-node.

[0062] Since the data acquisition system of the aviation power distribution center mainly acquires and stores the operating status information and data of each device in the power distribution center and reports them to the RIU via the HB6096 bus, the patent information retrieved above cannot meet the design requirements of the aviation power distribution center.

[0063] To address the problems in the prior art, embodiments of the present invention provide a data acquisition system and method for an aviation power distribution center based on CAN bus networking.

[0064] The present invention provides the following specific embodiments, which can be combined with each other. For the same or similar concepts or processes, they may not be described again in some embodiments.

[0065] Figure 1 This is a schematic diagram of a data acquisition system for an aviation power distribution center based on a CAN bus network, provided as an embodiment of the present invention. Figure 1 As shown in the figure, the data acquisition system for an aviation power distribution center based on CAN bus networking provided in this embodiment of the invention includes: all devices in the aviation power distribution center that have data transmission requirements, and a data acquisition unit.

[0066] like Figure 1 In the data acquisition system of the aviation power distribution center based on CAN bus networking shown, the data acquisition unit is configured as the master node of the CAN bus network, and each device in the aviation power distribution center with data transmission requirements is configured as a sub-node of the CAN bus network. All devices in the aviation power distribution center with data transmission requirements are connected to the remote interface unit 2 through the bus.

[0067] The data acquisition device in this embodiment of the invention includes: a processor chip with at least two eCAN interfaces, a CAN transceiver connected to each eCAN interface, and a first communication transceiver and a second communication transceiver; all equipment in the aviation power distribution center with data transmission requirements are connected to at least two CAN transceivers in the data acquisition device through at least two CAN buses; the output interface of the processor chip is connected to the remote interface unit 1 through the first communication transceiver, and the other output interface of the processor chip is connected to the ground maintenance equipment through the second communication transceiver, for downloading the operating data information of each equipment in the power distribution center recorded by the data acquisition device to the ground maintenance equipment.

[0068] In addition, in the data acquisition system, all devices in the aviation power distribution center that have data transmission requirements send operating data information to the remote interface unit 2 via the bus, and transmit the operating data information of all devices to the data acquisition unit via at least two CAN buses, so that the data acquisition unit can send it to the remote interface unit 1 via the first communication transceiver; and during ground maintenance, the operating data information of each device in the power distribution center recorded by the data acquisition unit is downloaded to the ground maintenance equipment.

[0069] like Figure 1As shown, in a specific implementation, the SPI serial bus interface inside the processor chip is connected to the remote interface unit 1 through the first communication transceiver; the SCI / UART communication interface inside the processor chip is connected to the ground maintenance equipment through the second communication transceiver, which is used to download the operating data information of each device in the power distribution center recorded by the data acquisition device to the ground maintenance equipment.

[0070] Since the RIU provides power distribution center data to the electromechanical integrated management computer, and the higher-level system makes important decisions about flight missions based on the power distribution center's operational status, the real-time reporting of operational data from various devices within the power distribution center to the RIU via the HB6096 bus significantly impacts the reliability and safety of aircraft flight missions and the operation of the aircraft's power distribution center. Therefore, redundancy in data acquisition, communication, and storage is essential. Thus, this invention, with a limited number of HB6096 bus interfaces, employs a CAN bus network. In addition to storing critical data from devices within the power distribution center and reporting it to one RIU via the HB6096 bus, another RIU utilizes a CAN bus network to acquire real-time operational data from various devices within the power distribution center. This CAN communication data is then converted to the HB6096 communication format and reported to the other RIU, forming a redundant communication channel for the data acquisition system. Furthermore, this data acquisition system can store and back up data in real-time for future fault tracing. Therefore, in cases where communication or data storage anomalies occur due to the complex electromagnetic and natural environment on board a device in the power distribution center during flight, the technical solution provided by the embodiments of this invention effectively ensures the effective storage of critical aircraft operation data, providing strong protection for the reliability and safety of aircraft flight missions.

[0071] The following is a detailed description of the data acquisition system and method for an aviation power distribution center based on CAN bus networking provided by the embodiments of the present invention.

[0072] like Figure 1 As shown in the embodiment of the present invention, in the data acquisition system of an aviation power distribution center based on CAN bus networking, the system is configured with a data acquisition unit as the master node of the CAN bus network, and the 32 devices within the power distribution center as child nodes, based on the design requirements of 32 devices, a data capacity of no less than 12 bytes per device, and a communication cycle of 200ms for the HB6096 bus. The data acquisition unit includes a processor chip with at least two built-in eCAN interfaces, such as an ARM (STM32F407) chip or a DSP (TMS320F28335) chip, employing a two-way bus communication network topology, and a CAN communication baud rate configured at 1 Mbit / s.

[0073] To meet the redundancy design requirements for onboard communication and storage, the data acquisition system of the aviation power distribution center is required to provide operational data information to remote interface unit 1 and remote interface unit 2 respectively. Limited by the number of HB6096 bus interfaces, on the one hand, the 32 devices within the power distribution center upload operational data information to remote interface unit 2 via the HB6096 bus interface and receive instructions from remote interface unit 2; on the other hand, a data acquisition unit based on a CAN bus network acquires the operational data information of each device within the power distribution center, and then reports the operational data information to remote interface unit 1 via the HB6096 bus interface of the data acquisition unit. In specific implementation, the HB6096 bus baud rate is configured to be 100 Kbit / s.

[0074] The data acquisition system of the aviation power distribution center based on CAN bus networking mainly consists of data acquisition units and all equipment in the aviation power distribution center with data transmission requirements (i.e., the above 32 devices). Its main functions are described in detail below:

[0075] (1) The aviation power distribution center has all the equipment required for data transmission:

[0076] Figure 1 The 32 devices mentioned can include: contactor control and protection units, power monitoring and control protection units, and other 32 devices within the power distribution center (i.e., 32 devices in total). Figure 1 The system, consisting of devices 1 through 32, primarily enables real-time monitoring and protection of power supply and conversion control within the power distribution center, as well as contactors, circuit breakers, diodes, and other equipment. It also facilitates real-time status communication reporting and storage of key operating parameters. Each of the 32 devices has one CAN bus interface, one HB6096 bus interface, and one RS422 bus interface. Devices 1 through 16 act as communication sub-nodes, connected to the data acquisition unit (the communication master node) via the first CAN bus. Devices 17 through 32 act as communication sub-nodes, connected to the data acquisition unit (the communication master node) via the second CAN bus sub-node. Under normal operating conditions, each device periodically uploads its own operating data to the remote interface unit 2 via its respective HB6096 bus interface. Furthermore, upon receiving instructions from the data acquisition unit via the CAN bus interface, each device immediately feeds back the relevant operating data to the data acquisition unit via the corresponding CAN bus. During ground maintenance, the ground maintenance equipment downloads the data stored by each device via the RS422 bus interface.

[0077] (2) Data Acquisition Device:

[0078] The main function is to collect and store operating data from 32 devices within the power distribution center via CAN bus, and to report this data to remote interface unit 1 via HB6096 bus, enabling scheduling and processing of multi-channel communication networks. Specifically, the data acquisition unit has two CAN communication interfaces, one RS422 communication interface, and one HB6096 bus interface. The first CAN communication interface is connected to the CAN bus interfaces of devices 1 to 16 in a bus topology; the second CAN communication interface is connected to the CAN bus interfaces of devices 17 to 32 in a bus topology. Under normal operating conditions, after acquiring the operating data from the 32 devices via the first and second CAN communication interfaces, the data acquisition unit converts the data into HB6096 communication data format using its internal processor chip and reports it to remote interface unit 1 via the HB6096 bus interface. During ground maintenance, the ground maintenance equipment downloads the operating data from each device within the power distribution center recorded by the data acquisition unit via the RS422 bus interface.

[0079] In practical implementation, the data acquisition unit uses an ARM (STM32F407) chip or a DSP (TMS320F28335) chip as the processor chip. It has at least two built-in eCAN communication interfaces, each connected to at least two corresponding CAN transceivers. It also has one built-in SCI / UART communication interface connected to an RS422 transceiver for signal amplification and isolation. The ARM / DSP chip's built-in SPI serial bus interface connects to the "ARINC429 communication chip and transceiver" (i.e., the first communication transceiver) to control and transmit / receive HB6096 communication. The ARINC429 communication chip has a FIFO depth of 32×32 bits. The ARM / DSP chip also connects to external memory NVSRAM, FLASH1, and FLASH2 via a data bus to store data within the power distribution center.

[0080] In one implementation of this invention, the method of sending data to the remote interface unit 1 is as follows: based on the requirements of the HB6096 communication task cycle (200ms), the maximum baud rate of the HB6096 bus is 100Kbit / s, the sum of the data capacity of all devices is not less than 3072 bits, and the FIFO depth of the ARINC429 communication chip is 32×32 bits, the operating data information of each device collected in the data acquisition unit is sent to the remote interface unit 1 via the HB6096 bus communication in a 32×32-bit communication data packet manner. The method of sending the communication data packet is: with a sending interval of 14ms, all communication data packets are sent in 6 times.

[0081] based on Figure 1The data acquisition system for an aviation power distribution center, shown, is based on a CAN bus network. The data acquisition unit primarily handles the scheduling and data storage of tasks across multiple communication networks. Specifically, it uses timers to set task cycle flags for 2ms, 14ms, 350ms, 400ms, and the first 200ms (relative to the 400ms task cycle). Upon reaching the set timer, the corresponding task is executed. Figure 2 The diagram shows a flowchart of a data acquisition method for an aviation power distribution center based on a CAN bus network, as provided in an embodiment of the present invention. Figure 2 As shown, the specific implementation method of this data acquisition method is as follows:

[0082] Step 1: Set the CAN communication task completion flag to invalid, set the CAN communication task count range to 0-32, and the task counting interval to 2ms. When the CAN communication task completion flag is invalid, the data acquisition unit acquires the operating data information of each device in the power distribution center through the first CAN bus and the second CAN bus every 2ms. Figure 2 As shown, the specific task for CAN communication task counting is as follows:

[0083] 0 — The data collector sends data request instruction 1 to devices 1 and 17 respectively, using the ID numbers as the sending email addresses for devices 1 and 17.

[0084] 1~31——The data acquisition unit receives the Kth packet of CAN communication data from device X and device (X+16) with ID numbers respectively, and sends data request command L to device Y and device (Y+16);

[0085] The count range of X is 1 to 16, and it increments by 1 each time it reaches an even number of task counts. The values ​​of K and L depend on the CAN communication task count. If the CAN communication task count is odd, then K is 1 and L is 2; if the CAN communication task count is even, then K is 2 and L is 1.

[0086] 32—The data acquisition unit receives the second packet of CAN communication data from devices 16 and 32 with ID numbers respectively. It sets the CAN communication task completion flag to valid and the HB6096 communication completion flag to invalid. At this point, the reception of data from all devices is complete.

[0087] Step 2: When the CAN communication task completion flag is valid, set the HB6096 communication task count range to 0-5, with a task count interval of 14ms. When the HB6096 communication task completion flag is invalid, the data acquisition unit converts the operating data of each device in the power distribution center acquired via CAN communication into HB6096 communication format. This data is then reported to remote interface unit 1 via the HB6096 communication interface every 14ms and stored in the processor chip's external NVSRAM via the data bus. When the HB6096 communication task count reaches 5 (i.e., 6 transmissions), the HB6096 communication completion flag is set to valid.

[0088] Step 3: When the HB6096 communication completion flag is valid and the 350ms task cycle flag is valid, set the FLASH storage flag to valid, and read the data stored in the NVSRAM within the last two HB6096 communication cycles and transfer them sequentially to the external FLASH of the processor chip. After storage is completed, set the FLASH storage flag to invalid and clear the 350ms task cycle flag to invalid.

[0089] Step 4: If the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid, determine whether FLASH erasure is required based on the current tail pointer stored in FLASH. If so, perform FLASH erasure.

[0090] It should be noted that the data storage function implemented by the data acquisition device mainly includes fault data storage and monitoring data storage, such as... Figure 1 As shown, in order to strictly control the overall weight and volume of the equipment on the machine, the data acquisition device in this embodiment of the invention uses one NVSRAM storage chip to realize fault data storage with a small data volume, and uses two large-capacity FLASH storage chips to realize monitoring data storage with a large data volume.

[0091] Since both NVSRAM and FLASH memory chips are non-volatile memories, they can retain stored data even after power failure. NVSRAM offers fast byte-by-byte access, while FLASH has a maximum programming (writing) unit of 256 bytes and a minimum programming (writing) unit of 1 byte. Furthermore, data must be erased before writing, with the minimum erase unit being a sector. Therefore, considering the timeliness of data recording, NVSRAM is used to record data during system malfunctions, while FLASH periodically records system monitoring data, both using a cyclic overwrite storage method. To prevent data loss during FLASH erasure, the NVSRAM is divided into three areas: Area 1 stores information such as the NVSRAM fault record tail pointer, FLASH record tail pointer, monitoring backup data head pointer, and tail pointer; Area 2 cyclically stores system fault data; and Area 3 stores monitoring backup data. Area 3 stores the monitoring backup data within the 400ms period.

[0092] In one implementation of this invention, during step two above, when the data acquisition device performs the HB6096 communication task, after each 32×32-bit communication data packet is sent to the HB6096 communication interface, the data packet is stored in region 3 of the NVSRAM. The specific storage method is as follows:

[0093] Step 21: Update the 32nd bit of the 32-bit data in the HB6096 communication format. The update method is as follows: sum the data bits of the HB6096 communication, i.e., bits 11 to 29. If the sum is even, set bit 32 to 1; if the sum is odd, clear bit 32 to 0.

[0094] Step 22: After the data content is updated, the 32×32-bit communication data of the packet is transferred to the cache array;

[0095] Step 23: If the task cycle flag for the previous 200ms is valid, perform the following operations:

[0096] S23a, Read the tail pointer of the monitoring backup data from area 1 of NVSRAM and perform segment swapping on the tail pointer of the monitoring backup data;

[0097] S23b, store the updated monitoring backup data tail pointer as the monitoring backup data head pointer in NVSRAM area 1;

[0098] S23c stores the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address. After storage is completed, the updated monitoring backup data tail pointer is stored in NVSRAM area 1.

[0099] Step 24: If the task cycle flag for the previous 200ms is invalid, perform the following operations:

[0100] S24a: Read the tail pointer of the monitoring backup data from NVSRAM area 1, and perform segment swapping on the tail pointer of the monitoring backup data;

[0101] S24b: Store the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address. After storage, store the updated monitoring backup data tail pointer into NVSRAM area 1.

[0102] Furthermore, in this implementation, the method for processing the tail pointer is as follows: the maximum address in region 3 of NVSRAM is compared with the tail pointer of the monitoring backup data. If the difference is less than 32×32 bits, the tail pointer of the monitoring backup data is set to the initial address value of the tail pointer of the monitoring backup data, and the updated tail pointer of the monitoring backup data is stored in region 1 of NVSRAM.

[0103] In one implementation of this invention, based on the amount of monitoring data stored in a 400ms cycle and the FLASH single-page data length of 256 bytes, the data within the last two HB6096 communication cycles requires 6 pages of FLASH storage space. Therefore, in step three above, when the data acquisition unit executes the 350ms cycle task, if the FLASH storage flag is valid, it transfers one page of data from NVSRAM to FLASH every 2ms, repeating this process 6 times. The specific storage method is as follows:

[0104] Step 31: Read the FLASH record tail pointer and monitoring backup data head pointer in NVSRAM area 1;

[0105] Step 32, perform segment switching based on the FLASH record tail pointer: compare the maximum address of FLASH storage with the FLASH record tail pointer. If the difference is less than or equal to Δ1, set the FLASH record tail pointer to the initial address value of the FLASH record tail pointer and store the updated FLASH record tail pointer in NVSRAM area 1. Otherwise, no processing is performed. Here, Δ1 is 256 bytes.

[0106] Step 33: Read 256 bytes of data sequentially from NVSRAM area 3, starting from the monitoring backup data header pointer, and then store them sequentially into the FLASH memory starting from the FLASH record tail pointer; after storage, store the updated FLASH record tail pointer into NVSRAM area 1.

[0107] Step 34: Increment the FLASH task count by 1. If the FLASH task count is greater than or equal to 6, clear the FLASH task count to 0 and set the FLASH storage flag to invalid and the 350ms task cycle flag to invalid; otherwise, do nothing.

[0108] In one implementation of this invention, in step four above, based on the FLASH erasure time of the used 300ms, the data collector executes the FLASH erasure task when it determines that the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid. Specific implementation methods include:

[0109] Step 41: Read the FLASH record tail pointer from NVSRAM area 1;

[0110] Step 42: Calculate the sector where the current FLASH record tail pointer is located based on the FLASH record tail pointer;

[0111] Step 43: Compare the maximum address of the current sector with the FLASH record tail pointer. If the difference is less than or equal to Δ2, then set the erase flag to valid; otherwise, set the erase flag to invalid. Here, Δ2 is 1536 bytes.

[0112] Step 44: If the erase flag is valid, and the sector where the current FLASH record tail pointer is located is the sector with the maximum number of times FLASH can be used, then set the FLASH erase address to the initial address value of the FLASH record tail pointer; if the sector where the current FLASH record tail pointer is located is smaller than the sector with the maximum number of times FLASH can be used, then set the FLASH erase address to the starting address of the next sector; otherwise, do not process it.

[0113] Step 45: FLASH performs sector erasure according to the FLASH erase address.

[0114] To address the issue of communication or data storage anomalies in aviation power distribution centers caused by the complex electromagnetic and natural environments on board during aircraft flight, this invention provides a data acquisition system and method for aviation power distribution centers based on a CAN bus network to meet the redundancy design requirements for onboard communication and storage. Specifically, it proposes using a CAN bus-based data acquisition system for aviation power distribution centers as a data redundancy design, fully utilizing the high reliability and security, simple topology, and good transmission distance and speed advantages of the CAN bus's cyclic redundancy check (CRC) function. The aviation power distribution center provides operational data information to remote interface unit 1 and remote interface unit 2. On one hand, each device in the power distribution center uploads communication data to remote interface unit 2 and receives instructions from remote interface unit 2 via the HB6096 bus interface. On the other hand, the data acquisition system based on the CAN bus network acquires operational data from multiple devices in the power distribution center with data transmission needs, and then transmits this data to remote interface unit 1 via the HB6096 bus interface.

[0115] Furthermore, to fully consider the weight and size of the designed data acquisition system, the system leverages the advantages of NVSRAM (small capacity but fast byte-by-byte access) and FLASH (large capacity but requires erasure before access). Both NVSRAM and FLASH are used. Fault data is stored in NVSRAM to ensure speed and timeliness; backup monitoring data is stored in NVSRAM and periodically transferred to FLASH, avoiding reliability issues during FLASH erasure. This provides strong assurance for the reliability of communication and data storage in aircraft flight, and is of great significance in the aviation and aerospace fields.

[0116] The following implementation example illustrates the method for implementing the data acquisition system and method for an aviation power distribution center based on CAN bus networking provided in this invention.

[0117] Implementation Example

[0118] like Figure 1 As shown, the data acquisition system for the aviation power distribution center provided in this implementation example mainly consists of one data acquisition unit and 32 devices within the power distribution center. On one hand, the 32 devices in the power distribution center upload communication data to the remote interface unit 2 and receive instructions from the remote interface unit 2 via the HB6096 bus interface. On the other hand, the system acquires the operating data of each device within the power distribution center through a CAN bus-based network data acquisition system, and then reports it to the remote interface unit 1 via the HB6096 bus interface. Furthermore, the data acquisition unit is the master node of the CAN bus network, and the 32 devices in the power distribution center are the sub-nodes of the CAN bus network. The specific implementation method for data acquisition by the data acquisition system is as follows:

[0119] S1. After the system is powered on, the data acquisition unit and 32 devices in the power distribution center will perform the power-on initialization function respectively. The variables such as the CAN communication task completion flag, HB6096 communication completion flag, and FLASH storage flag will be invalid.

[0120] S2. First, when the data acquisition unit determines that the CAN communication task completion flag is invalid, it sends data request commands to the CAN communication sub-nodes sequentially at 2ms intervals according to the CAN communication task count, and then responds with data reception from the sub-nodes in the next 2ms task completion period. The CAN communication sub-nodes perform reception queries at 200us intervals and complete the CAN communication response within 200us.

[0121] S3. After the CAN communication task count of the data acquisition unit reaches 32, set the CAN communication task completion flag to valid and the HB6096 communication completion flag to invalid.

[0122] S4. Next, when the data acquisition unit determines that the CAN communication task completion flag is valid and the HB6096 communication completion flag is invalid, it converts the received 32 CAN communication sub-node information into HB6096 communication data format at 14ms intervals, and sends 32×32bit data packets sequentially to remote interface unit 1 according to the HB6096 communication task count. The communication data packets are then transferred to area 3 of NVSRAM. The specific storage method is as follows:

[0123] S41. Update the 32nd bit of the 32-bit data in the HB6096 communication format. The update method is as follows: sum the bits of the HB6096 communication data bits, i.e., bits 11 to 29. If the sum is even, set bit 32 to 1; if the sum is odd, clear bit 32 to 0.

[0124] S42. After the data content is updated, the 32×32-bit communication data of the packet is transferred to the cache array;

[0125] S43. If the task cycle flag for the previous 200ms is valid, perform the following operations:

[0126] a) Read the monitoring backup data tail pointer from NVSRAM area 1 and perform segment switching on the monitoring backup data tail pointer: compare the maximum address of NVSRAM area 3 with the monitoring backup data tail pointer. If the difference is less than 32×32 bits, set the monitoring backup data tail pointer to the initial address value of the monitoring backup data tail pointer and store the updated monitoring backup data tail pointer into NVSRAM area 1.

[0127] b) Store the updated monitoring backup data tail pointer as the monitoring backup data head pointer in NVSRAM area 1;

[0128] c) Store the contents of the cache array sequentially starting from the tail pointer of the monitoring backup data. After storage, store the updated tail pointer of the monitoring backup data into NVSRAM area 1.

[0129] S44. If the task cycle flag for the first 200ms is deemed invalid, perform the following operations:

[0130] a) Read the tail pointer of the monitoring backup data from NVSRAM area 1 and perform segment swapping on the tail pointer of the monitoring backup data;

[0131] b) Store the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address. After storage, store the updated monitoring backup data tail pointer into NVSRAM area 1.

[0132] S5. When the communication task count of the data acquisition unit HB6096 reaches 5, the communication completion flag of HB6096 is set to valid.

[0133] S6. When the data acquisition unit determines that the 350ms task cycle flag is valid, it also determines that the FLASH storage flag is valid. At 2ms intervals, it reads 256 bytes of monitoring data from NVSRAM area 3 and transfers it to FLASH once. The specific storage method is as follows:

[0134] S61. Read the FLASH record tail pointer and monitoring backup data head pointer in NVSRAM area 1;

[0135] S62. Perform segment switching based on the FLASH record tail pointer: Compare the maximum address of FLASH storage with the FLASH record tail pointer. If the difference is less than or equal to Δ1, set the FLASH record tail pointer to the initial address value of the FLASH record tail pointer and store the updated FLASH record tail pointer in NVSRAM area 1. Otherwise, do not perform any processing. Here, Δ1 is 256 bytes.

[0136] S63. Read 256 bytes of data sequentially from NVSRAM region 3, starting at the monitoring backup data header pointer, and then store them sequentially into the FLASH memory starting at the FLASH record tail pointer. After storage, store the updated FLASH record tail pointer into NVSRAM region 1.

[0137] S64. Increment the FLASH task count by 1. If the detected FLASH task count is greater than or equal to 6, clear the FLASH task count to 0 and set the FLASH storage flag to invalid and the 350ms task cycle flag to invalid; otherwise, do nothing.

[0138] S7. When the data collector determines that the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid, it executes the FLASH erase task. The specific method is as follows:

[0139] S71. Read the FLASH record tail pointer from NVSRAM area 1;

[0140] S72. Calculate the sector where the current FLASH record tail pointer is located based on the FLASH record tail pointer;

[0141] S73. Compare the maximum address of the current sector with the FLASH record tail pointer. If the difference is less than or equal to Δ2, set the erase flag to valid; otherwise, set the erase flag to invalid. Here, Δ2 is 1536 bytes.

[0142] S74. When the erase flag is valid, if the sector where the current FLASH record tail pointer is located is the sector with the maximum number of times FLASH can be used, then the FLASH erase address is set to the initial address value of the FLASH record tail pointer; if the sector where the current FLASH record tail pointer is located is smaller than the sector with the maximum number of times FLASH can be used, then the FLASH erase address is set to the starting address of the next sector; otherwise, no action is taken.

[0143] S75, FLASH performs sector erasure according to the FLASH erase address.

[0144] While the embodiments disclosed in this invention are as described above, they are merely illustrative of the embodiments to facilitate understanding of the invention and are not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in the form and details of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A data acquisition system for an aviation power distribution center based on CAN bus networking, characterized in that, include: The aviation power distribution center contains all equipment requiring data transmission, including data acquisition devices. The data acquisition unit is configured as the master node of the CAN bus network, and each device in the aviation power distribution center with data transmission requirements is configured as a sub-node of the CAN bus network. All devices in the aviation power distribution center with data transmission requirements are connected to the remote interface unit 2 via the bus. The data acquisition unit includes: a processor chip with at least two eCAN interfaces, a CAN transceiver connected to each eCAN interface, and a first communication transceiver and a second communication transceiver; all equipment in the aviation power distribution center with data transmission requirements is connected to at least two CAN transceivers in the data acquisition unit through at least two CAN buses, the output interface of the processor chip is connected to the remote interface unit 1 through the first communication transceiver, and the other output interface of the processor chip is connected to the ground maintenance equipment through the second communication transceiver; In the data acquisition system, all devices in the aviation power distribution center that have data transmission requirements send operating data information to the remote interface unit 2 via the HB6096 bus, and transmit the operating data information of all devices to the data acquisition unit via at least two CAN buses, so that the data acquisition unit can send it to the remote interface unit 1 via the first communication transceiver; and during ground maintenance, the operating data information of each device in the power distribution center recorded by the data acquisition unit is downloaded to the ground maintenance equipment.

2. The data acquisition system for an aviation power distribution center based on CAN bus networking according to claim 1, characterized in that, Each device in the aviation power distribution center that has data transmission requirements has one HB6096 bus, one RS422 bus interface, and one CAN bus interface. Each device is connected to the remote interface unit 2 through one HB6096 bus interface. Some devices are connected to the data acquisition unit, which is the communication master node, through the first CAN bus as communication sub-nodes. Other devices are connected to the data acquisition unit, which is the communication master node, through the second CAN bus sub-node. Under normal operating conditions, each device periodically uploads its own operating data information to the remote interface unit 2 through its respective HB6096 bus interface; After each device receives a command from the data acquisition unit via the CAN bus interface, it feeds back the relevant operating data information to the data acquisition unit via the corresponding CAN bus. During ground maintenance, the ground maintenance equipment downloads the data stored in each device via the RS422 bus interface.

3. The data acquisition system for an aviation power distribution center based on CAN bus networking according to claim 2, characterized in that, The data acquisition unit has two CAN communication interfaces, one RS422 communication interface, and one HB6096 bus interface; the first CAN communication interface is connected to the CAN bus interface of some of the devices in a bus topology; the second CAN communication interface is connected to the CAN bus interface of the other devices in a bus topology. The data acquisition unit is used to acquire the operating data information of each device in the power distribution center from the first CAN communication interface and the second CAN communication interface under normal operating conditions. Then, its internal processor chip converts the data into the HB6096 communication data format and reports it to the remote interface unit 1 through the HB6096 bus interface. It is also used to download the operating data information of each device in the power distribution center recorded by the data acquisition unit through the RS422 bus interface when performing ground maintenance.

4. A data acquisition method for an aviation power distribution center based on CAN bus networking, characterized in that, The data acquisition system for the aviation power distribution center based on CAN bus networking, as described in any one of claims 1 to 3, is used to perform a data acquisition method on the aviation power distribution center. The power distribution center is configured to have 32 devices, and the processor chip of the data acquisition unit is externally connected to NVSRAM and FLASH. The method includes: Step 1: Set the CAN communication task completion flag to invalid, set the CAN communication task count range to 0-32, and the task count interval to 2ms; when the CAN communication task completion flag is invalid, the data acquisition unit acquires the operating data information of each device in the power distribution center through the first CAN bus and the second CAN bus at a period of 2ms. Step 2: When the CAN communication task completion flag is valid, set the HB6096 communication task count range to 0-5 and the task count interval to 14ms. When the HB6096 communication task completion flag is invalid, the data acquisition unit will convert the operating data of each device in the power distribution center collected through CAN communication into HB6096 communication format. Every 14ms, the data will be reported to the remote interface unit 1 through the HB6096 communication interface and stored in the NVSRAM connected to the processor chip through the data bus. When the HB6096 communication task count reaches 5, the HB6096 communication completion flag will be set to valid. Step 3: When the HB6096 communication completion flag is valid and the 350ms task cycle flag is valid, set the FLASH storage flag to valid, and read the data stored in the NVSRAM within the last two HB6096 communication cycles and transfer them sequentially to the FLASH external to the processor chip. After storage is completed, set the FLASH storage flag to invalid and clear the 350ms task cycle flag to invalid. Step 4: If the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid, determine whether FLASH erasure is required based on the current tail pointer of FLASH storage. If erasure is required, then FLASH erasure is performed.

5. The data acquisition method for an aviation power distribution center based on CAN bus networking according to claim 4, characterized in that, The data acquisition device uses NVSRAM to record data when the system malfunctions, and uses FLASH to periodically record system monitoring data, both using a cyclic overwrite storage method. The NVSRAM is divided into three areas: Area 1 is used to store the NVSRAM fault record tail pointer, FLASH record tail pointer, monitoring backup data head pointer, and tail pointer; Area 2 is used to cyclically store system fault data; Area 3 is used to store monitoring backup data; and Area 3 is used to store the monitoring backup data within the 400ms period.

6. The data acquisition method for an aviation power distribution center based on CAN bus networking according to claim 5, characterized in that, The method further includes: Every 2ms, check if the data acquisition system has failed. If a failure occurs, store the fault data in bytes in area 2 of NVSRAM.

7. The data acquisition method for an aviation power distribution center based on CAN bus networking according to claim 5, characterized in that, In step 2, during the execution of the HB6096 communication task, after each 32×32-bit communication data packet is sent to the HB6096 communication interface, the data packet is stored in area 3 of the NVSRAM. The specific storage method includes: Step 21: Update the 32nd bit of the 32-bit data in the HB6096 communication format. The update method is as follows: sum the data bits of the HB6096 communication, i.e., bits 11 to 29. If the sum is even, set bit 32 to 1; if the sum is odd, clear bit 32 to 0. Step 22: After the data content is updated, transfer the 32×32-bit communication data of the data packet to the buffer array; Step 23: If the task cycle flag of the previous 200ms is valid, perform the following operations: S23a, Read the tail pointer of the monitoring backup data from area 1 of NVSRAM and perform segment swapping on the tail pointer of the monitoring backup data; S23b, store the updated monitoring backup data tail pointer as the monitoring backup data head pointer in NVSRAM area 1; S23c, stores the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address, and after storage is completed, stores the updated monitoring backup data tail pointer into NVSRAM area 1; Step 24: If the task cycle flag for the previous 200ms is invalid, perform the following operations: S24a, Read the tail pointer of the monitoring backup data from NVSRAM area 1 and perform segment swapping on the tail pointer of the monitoring backup data; S24b: Store the contents of the cache array sequentially with the monitoring backup data tail pointer as the starting address. After storage, store the updated monitoring backup data tail pointer into NVSRAM area 1.

8. The data acquisition method for an aviation power distribution center based on CAN bus networking according to claim 7, characterized in that, The method for performing segment swapping on the tail pointer is as follows: The maximum address in NVSRAM region 3 is compared with the monitoring backup data tail pointer. If the difference is less than 32×32 bits, the monitoring backup data tail pointer is set to the initial address value of the monitoring backup data tail pointer, and the updated monitoring backup data tail pointer is stored in NVSRAM region 1.

9. The data acquisition method for an aviation power distribution center based on CAN bus networking according to claim 8, characterized in that, In step 3, when the data acquisition unit executes a 350ms cycle task, if the FLASH storage flag is valid, it transfers one page of data from NVSRAM to FLASH every 2ms, repeating this process six times. The storage method includes: Step 31: Read the FLASH record tail pointer and monitoring backup data head pointer in NVSRAM area 1; Step 32, perform segment switching based on the FLASH record tail pointer: compare the maximum address of FLASH storage with the FLASH record tail pointer. If the difference is less than or equal to Δ1, set the FLASH record tail pointer to the initial address value of the FLASH record tail pointer and store the updated FLASH record tail pointer in NVSRAM area 1. Otherwise, no processing is performed. Here, Δ1 is 256 bytes. Step 33: Read 256 bytes of data sequentially from NVSRAM area 3, starting from the monitoring backup data header pointer, and then store them sequentially into the FLASH memory starting from the FLASH record tail pointer; after storage, store the updated FLASH record tail pointer into NVSRAM area 1. Step 34: Increment the FLASH task count by 1; if the FLASH task count is greater than or equal to 6, clear the FLASH task count to 0 and set the FLASH storage flag to invalid and the 350ms task cycle flag to invalid; otherwise, do not process.

10. The data acquisition method for an aviation power distribution center based on CAN bus networking according to claim 9, characterized in that, In step 4 above, based on the FLASH erase time of 300ms, the data collector executes the FLASH erase task when it determines that the 350ms task cycle flag is invalid and the 400ms task cycle flag is valid. Specific implementation methods include: Step 41: Read the FLASH record tail pointer from NVSRAM area 1; Step 42: Calculate the sector where the current FLASH record tail pointer is located based on the FLASH record tail pointer; Step 43: Compare the maximum address of the current sector with the FLASH record tail pointer. If the difference is less than or equal to Δ2, then set the erase flag to valid; otherwise, set the erase flag to invalid. Here, Δ2 is 1536 bytes. Step 44: If the erase flag is valid, and the sector where the current FLASH record tail pointer is located is the sector with the maximum number of times FLASH can be used, then set the FLASH erase address to the initial address value of the FLASH record tail pointer; if the sector where the current FLASH record tail pointer is located is smaller than the sector with the maximum number of times FLASH can be used, then set the FLASH erase address to the starting address of the next sector; otherwise, do not process it. Step 45: FLASH performs sector erasure according to the FLASH erase address.

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