A steam turbine safety monitoring system based on CANFD bus communication

Abstract

A steam turbine safety monitoring system based on CANFD bus communication belongs to the field of steam turbine TSI safety monitoring. To address the problems of low communication speed, supply chain risks due to reliance on imported core chips, poor channel reliability, and high development and maintenance costs caused by the large variety of functional cards in existing TSI systems, the system includes: a communication card acting as the master, communicating with multiple functional cards via the CANFD bus; functional cards acting as slaves, including data processing circuits and channel circuits; the data processing circuit using an MCU as the core processor and excluding a CPLD; channel circuits for acquiring or outputting analog signals, with chips in the channel circuits possessing both ADC and DAC functions; a standardized interface connecting the data processing circuit and the channel circuit; and communication between the communication card and functional cards using the CANFD protocol in a master-slave structure. This system is applicable to various steam turbine safety monitoring applications.

Description

Technical Field

[0001] This invention relates to a steam turbine safety monitoring system based on CANFD bus communication, belonging to the field of steam turbine TSI safety monitoring. Background Technology

[0002] Steam turbines are core power equipment in industrial sectors such as power plants, and their operating status directly affects the safety and stability of the entire system. Therefore, steam turbines are typically equipped with a TSI (Turbine Safety Monitoring) system. The Steam Turbine Safety Monitoring (TSI) system is a permanent monitoring system that integrates protection and detection functions, and is an indispensable protection system for large rotating machinery. TSI can reliably monitor and store some important parameters during the unit's start-up and operation. It not only indicates the unit's operating status, records output signals, triggers alarms for exceeding numerical limits, and automatically shuts down the unit when danger signals occur, but also provides data for fault diagnosis.

[0003] The number of items that need to be monitored and protected for steam turbines increases with the increase of steam parameters, and varies from unit to unit. Generally, these include the following parameters: axial displacement monitoring, differential expansion monitoring, cylinder expansion monitoring, zero speed monitoring, speed monitoring, vibration monitoring, eccentricity monitoring, phase monitoring, and valve position indication.

[0004] In existing TSI systems, communication between the main controller and various function cards primarily uses the HDLC protocol. While this protocol was widely used in early industrial control, its communication rate is relatively low (typically 750Kbps), making it difficult to meet the high data throughput and real-time requirements of modern large-scale units. Furthermore, the core processing units of traditional function cards often use imported chips, such as STMicroelectronics' STR715 MCU and Xilinx's XC9536 CPLD. These chips not only face the risk of production halts but also have long procurement cycles, high costs, and pose supply chain security risks.

[0005] In analog signal acquisition, traditional circuits often employ a single ADC channel switching structure. While this is cost-effective, a failure in the ADC chip will cause all channels to fail, resulting in poor system reliability. Furthermore, the wide variety of functional cards and the different chip models used further complicate material management and development.

[0006] In recent years, domestically produced chips have made significant progress in performance, stability, and production capacity, making them capable of replacing imported chips. However, existing TSI systems have not yet been fully integrated with domestically produced chips and next-generation communication technologies for systematic optimization design, and still suffer from problems such as low communication speed, complex structure, and low localization rate. Summary of the Invention

[0007] The purpose of this invention is to solve the problems of low communication speed, supply chain risks due to reliance on imported core chips, poor channel reliability, and high development and maintenance costs caused by the large variety of functional cards in the existing TSI system, and to provide a steam turbine safety monitoring system based on CANFD bus communication.

[0008] The present invention discloses a turbine safety monitoring system based on CANFD bus communication, which includes:

[0009] At least one communication card acts as the host, communicating with multiple function cards via the CANFD bus;

[0010] Multiple function cards, acting as slave devices, each function card includes data processing circuitry and channel circuitry;

[0011] The data processing circuit uses an MCU as the core processor and does not include a CPLD;

[0012] The channel circuit is used to acquire or output analog signals, and the chip used in the channel circuit has both ADC and DAC functions.

[0013] The data processing circuit and the channel circuit are connected via a standardized interface;

[0014] The communication between the communication card and the function card adopts the CANFD protocol and a master-slave structure.

[0015] Preferably, the communication rate between the communication card and the function card is set to 500 Kbit / s for the arbitration segment and 2 Mbit / s for the data segment, with a maximum data field length of 64 bytes. The communication protocol specifies that the slave device should respond within 0.5 ms after receiving the instruction, release the bus within 100 μs after communication is completed, and the single communication time should not exceed 2 ms.

[0016] Preferably, the functional card adopts a modular structure, with the data processing circuit and the channel circuit designed as independent circuit boards. The data processing circuit, as a general core module, can be combined with channel circuits of different functions to form corresponding types of functional cards.

[0017] Preferably, the channel circuit consists of four channel boards, and the data processing circuit consists of two MCU core boards; the function card is assembled from two MCU core boards and four channel boards.

[0018] Preferably, the standardized interface between the data processing circuit and the channel circuit includes 73 I / O interfaces and 6 serial communication interfaces.

[0019] Preferably, the format of the extended frame ID in the CANFD protocol is: 4 bits priority, 2 bits transmitting role, 2 bits reserved, 8 bits function card address, and 8 bits control data.

[0020] Preferably, the priority is divided according to the communication direction and operation type as follows:

[0021] The priority of host write commands is 0x1h;

[0022] The priority of the host read command is 0x2h;

[0023] The priority of SOE-related operations is 0x3h;

[0024] The priority of the slave write response is 0x8h;

[0025] The priority of the slave device's read return is 0x9h;

[0026] The priority of slave SOE-related operations is 0xAh.

[0027] Preferably, the MCU is GigaDevice GD32C103VBT6.

[0028] Preferably, the chip that simultaneously has ADC and DAC functions is the Nanochip NSA2860.

[0029] Advantages of this invention: This invention proposes a turbine safety monitoring system based on CANFD bus communication. It uses domestically produced MCU and ADC / DAC chips as core components, eliminating reliance on imported chips, resolving supply chain security risks, shortening the procurement cycle, reducing costs, and achieving domestic substitution for TSI systems. Employing CANFD bus communication technology, the communication rate can reach up to 5Mbps, and the data field supports a maximum of 64 bytes. Compared to the traditional HDLC protocol's 750Kbps communication rate, this meets the high data throughput and real-time requirements of large-scale units. The channel circuit uses chips with both ADC and DAC functions, eliminating the need for channel switching and avoiding the problem of all channels failing due to ADC chip failure in traditional single-ADC switching structures, thus improving system reliability.

[0030] The functional cards adopt a modular design that separates the data processing circuitry from the channel circuitry. The data processing circuitry, as a general-purpose core module, can be combined with channel circuitry of different functions, reducing the types of cards and facilitating debugging, testing, and maintenance. The main components are exposed, resulting in good heat dissipation and convenient maintenance. The data processing circuitry uses a single MCU design, eliminating the CPLD, simplifying the hardware structure, and reducing the workload and difficulty of software development. Attached Figure Description

[0031] Fig. 1 This is a schematic diagram of the turbine safety monitoring system based on CANFD bus communication as described in this invention;

[0032] Fig. 2 This is a hardware circuit block diagram of the functional card described in this invention. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0035] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0036] Example 1:

[0037] The following is combined Figs. 1-2 This embodiment describes a turbine safety monitoring system based on CANFD bus communication, which includes:

[0038] At least one communication card acts as the host, communicating with multiple function cards via the CANFD bus;

[0039] Multiple function cards, acting as slave devices, each function card includes data processing circuitry and channel circuitry;

[0040] The data processing circuit uses an MCU as the core processor and does not include a CPLD;

[0041] The channel circuit is used to acquire or output analog signals, and the chip used in the channel circuit has both ADC and DAC functions.

[0042] The data processing circuit and the channel circuit are connected via a standardized interface;

[0043] The communication between the communication card and the function card adopts the CANFD protocol and a master-slave structure.

[0044] Furthermore, the communication rate between the communication card and the function card is set to 500 Kbit / s for the arbitration segment and 2 Mbit / s for the data segment, with a maximum data field length of 64 bytes. The communication protocol stipulates that the slave device must respond within 0.5 ms after receiving the instruction, release the bus within 100 μs after communication is completed, and the single communication time must not exceed 2 ms.

[0045] Furthermore, the functional card adopts a modular structure, with the data processing circuit and the channel circuit designed as independent circuit boards. The data processing circuit, as a general core module, can be combined with channel circuits of different functions to form corresponding types of functional cards.

[0046] Furthermore, the channel circuit consists of four channel boards, the data processing circuit consists of two MCU core boards, and the function card is assembled from two MCU core boards and four channel boards.

[0047] Furthermore, the standardized interface between the data processing circuit and the channel circuit includes 73 I / O interfaces and 6 serial communication interfaces.

[0048] Furthermore, the format of the extended frame ID in the CANFD protocol is: 4 bits priority, 2 bits transmitting role, 2 bits reserved, 8 bits function card address, and 8 bits control data.

[0049] Furthermore, the priority is divided according to the communication direction and operation type as follows:

[0050] The priority of host write commands is 0x1h;

[0051] The priority of the host read command is 0x2h;

[0052] The priority of SOE-related operations is 0x3h;

[0053] The priority of the slave write response is 0x8h;

[0054] The priority of the slave device's read return is 0x9h;

[0055] The priority of slave SOE-related operations is 0xAh.

[0056] Furthermore, the MCU model is GigaDevice GD32C103VBT6.

[0057] Furthermore, the chip that simultaneously has ADC and DAC functions is the Nanochip NSA2860.

[0058] like Fig. 1As shown, the communication card acts as the master unit, and multiple function cards act as slave units. The communication card and function cards communicate with each other via a CANFD bus. The communication card is responsible for exchanging data with the host computer or distributed processing unit (DPU) and for the unified scheduling and management of the function cards. The function cards are responsible for collecting various operating parameters of the turbine, such as axial displacement, differential expansion, cylinder expansion, speed, vibration, eccentricity, etc., or for executing corresponding control outputs.

[0059] like Fig. 2 As shown, the functional card adopts a modular design, with the hardware circuit divided into two parts according to function: a data processing circuit and a channel circuit. The data processing circuit uses a two-MCU core board design, with the core processor being the domestic GigaDevice GD32C103VBT6 MCU. This MCU is based on the ARM Cortex-M3 core, has rich peripheral interfaces and strong data processing capabilities, and supports the CANFD communication protocol. The data processing circuit does not include a CPLD, simplifying the hardware structure and reducing costs.

[0060] The channel circuit employs a four-channel board design, with each board responsible for the acquisition or output of analog signals from several channels. The chips used in the channel boards are the NSA2860 from Navitas Microelectronics, which combines ADC and DAC functions, enabling direct analog input acquisition and output control without the need for channel switching circuits. This design avoids the problem of all channels failing due to ADC chip failure, as seen in traditional single-ADC switching structures, thus improving system reliability.

[0061] The data processing circuit and the channel circuit are connected via a standardized interface, which includes 73 I / O interfaces and 6 serial communication interfaces, improving the board's versatility. Two MCU core boards and four channel boards are combined to form a complete functional card, with the main components exposed for easy debugging, testing, and maintenance.

[0062] Communication protocol design:

[0063] Communication between the communication card and the function card uses the CANFD protocol, and the specific specifications are as follows:

[0064] Communication rate: Arbitration segment is set to 500 Kbit / s, data segment is set to 2 Mbit / s, and the maximum length of the data field is 64 bytes.

[0065] Master-slave architecture: The communication card is the master, and the function cards are the slaves. Data cables must not be occupied when not in use for communication.

[0066] Response mechanism: The slave function card must respond within 0.5ms after receiving the master command; otherwise, the communication card will consider the communication timeout error to be true.

[0067] Bus release: The slave function card must release the data bus within 100μs after the data transmission is completed.

[0068] Communication duration: The communication time for a slave function card (from the time the master occupies the data bus to the time the slave finishes sending data) shall not exceed 2ms.

[0069] ID format: The extended frame ID consists of 29 bits, and the format is as follows:

[0070]

[0071] The extended frame ID consists of 29 bits. To retain the original module address and board type system and reduce the workload of code development, the first 4 bits of the ID are used as an independent priority area, and 2 bits are reserved and set to 0. When the sending role is a function card, the ID is set to 1, and when it is a communication card, the ID is set to 0.

[0072] Priority rules:

[0073]

[0074] The new TSI system uses the CANFD bus for data communication and transmission. Since CANFD is an upgraded version of CAN, it has a variable rate, with a maximum rate of 5Mbps and a maximum data length of 64 bytes. Compared with the communication rate of 750Kbps of HDLC, it achieves a significant improvement in communication speed.

[0075] Furthermore, the domestically produced MCU GD32C103VBT6 and the domestically produced ADC / DAC chip NSA2860 used in this embodiment achieve domestic substitution of the core chips of the TSI system. Compared with traditional imported chip solutions, this approach has advantages such as shorter procurement cycles, lower costs, and less susceptibility to international situations.

[0076] Furthermore, the modular design of the functional cards in this embodiment allows the data processing circuit to serve as a general core module, which can be combined with channel circuits of different functions to form corresponding types of functional cards, such as vibration monitoring cards, displacement monitoring cards, and speed monitoring cards, thereby reducing the types of cards and lowering development and maintenance costs.

[0077] In this invention, the communication rate is significantly improved by adopting CANFD bus communication technology; the system is made independent and controllable by using domestically produced core chips; and the maintainability and reliability of the system are improved by adopting modular design.

[0078] This invention possesses the advantages of domestic production and independent control, realizing TSI system functional cards with domestically produced chips as the core. The product is not affected by international circumstances, achieving independent control, and has ample supply, short procurement cycles, and reduced costs.

[0079] Modular design reduces PCB size, with key components exposed for easy debugging, testing, and repair.

[0080] The maximum data communication transmission rate can reach 5Mbps, and the maximum data length is 64 bytes, which is a significant improvement over the traditional HDLC communication rate of 750Kbps.

[0081] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A steam turbine safety monitoring system based on CANFD bus communication, characterized in that, It includes: At least one communication card acts as the host, communicating with multiple function cards via the CANFD bus; Multiple function cards, acting as slave devices, each function card includes data processing circuitry and channel circuitry; The data processing circuit uses an MCU as the core processor and does not include a CPLD; The channel circuit is used to acquire or output analog signals, and the chip used in the channel circuit has both ADC and DAC functions. The data processing circuit and the channel circuit are connected via a standardized interface; The communication between the communication card and the function card adopts the CANFD protocol and a master-slave structure.

2. The turbine safety monitoring system based on CANFD bus communication according to claim 1, characterized in that, The communication rate between the communication card and the function card is set to 500 Kbit / s for the arbitration segment and 2 Mbit / s for the data segment. The maximum length of the data field is 64 bytes. The communication protocol stipulates that the slave device should respond within 0.5 ms after receiving the instruction, release the bus within 100 μs after the communication is completed, and the single communication time should not exceed 2 ms.

3. The turbine safety monitoring system based on CANFD bus communication according to claim 1, characterized in that, The functional card adopts a modular structure, with the data processing circuit and the channel circuit designed as independent circuit boards. The data processing circuit, as a general core module, can be combined with channel circuits of different functions to form corresponding types of functional cards.

4. A turbine safety monitoring system based on CANFD bus communication according to claim 3, characterized in that, The channel circuit consists of four channel boards, and the data processing circuit consists of two MCU core boards; the function card is assembled from two MCU core boards and four channel boards.

5. A turbine safety monitoring system based on CANFD bus communication according to claim 1, characterized in that, The standardized interface between the data processing circuit and the channel circuit includes 73 I / O interfaces and 6 serial communication interfaces.

6. A turbine safety monitoring system based on CANFD bus communication according to claim 1, characterized in that, The format of the extended frame ID in the CANFD protocol is: 4 bits priority, 2 bits transmitting role, 2 bits reserved, 8 bits function card address, and 8 bits control data.

7. A turbine safety monitoring system based on CANFD bus communication according to claim 6, characterized in that, The priorities are divided according to the communication direction and operation type as follows: The priority of host write commands is 0x1h; The priority of the host read command is 0x2h; The priority of SOE-related operations is 0x3h; The priority of the slave write response is 0x8h; The priority of the data returned by the slave device is 0x9h; The priority of slave SOE-related operations is 0xAh.

8. A turbine safety monitoring system based on CANFD bus communication according to any one of claims 1-7, characterized in that, The MCU model is GigaDevice GD32C103VBT6.

9. A turbine safety monitoring system based on CANFD bus communication according to any one of claims 1-7, characterized in that, The chip that has both ADC and DAC functions is the Nanochip NSA2860.

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