A FOUNDATION fieldbus redundancy method and device

Abstract

The invention discloses a Foundation Fieldbus redundancy method and device, comprising a plurality of FF interface modules for generating and performing primary modulation messages; a FF redundant bus connected to the FF interface modules for message transmission; a Y-type FF network segment protector connected to the FF redundant bus for secondary message modulation; and a downstream instrument for receiving messages and performing signal feedback; each FF interface module generates and initially modulates a message and sends it to the FF redundant bus; the Y-type FF network segment protector receives all messages and selects one of the messages for decoding and secondary modulation according to a negotiation mechanism, and sends the secondary modulated message to the downstream instrument; the invention provides a plurality of FF interface modules and a plurality of FF redundant buses, each of which operates independently and is wired separately, thereby improving the reliability of FF communication; when one FF bus has a plurality of fault points, the other bus is completely unaffected, and the overall FF communication can be guaranteed to be normal.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a Foundation Fieldbus redundancy method and device. Background Art

[0002] FF (Foundation Fieldbus) uses the IEC61158-2 physical layer standard. FF is widely used abroad, and its application cases in process industries in China have also increased in recent years. However, it basically adopts a single bus topology.

[0003] Conventional FF applications have the following components:

[0004] 1) FF interface module: the interface module for FF to access the DCS system, realizing the conversion between FF protocol and DCS internal protocol;

[0005] 2) FF power regulator: To supply power to multiple FF instruments on the network segment, a dedicated FF distributor is required. Each bus needs to be equipped with an FF power regulator (redundant configuration is possible);

[0006] 3) FF junction box: All FF bus branches are connected to the main line in the junction box. The junction box is equipped with a built-in branch protector (also called a wiring module or a segment protector) or an FF bus safety barrier. The main line is connected to the FF power regulator on the system cabinet side, and the instrument is connected to the bus branch (one instrument is connected to one branch).

[0007] 4) FF bus cable: Generally, Class A cable is used, and the trunk cable and branch cable use the same type.

[0008] The single bus mode may cause partial or even the entire FF network to be paralyzed when the FF interface module or FF network components are damaged (FF power regulator, FF segment protector / FF bus safety barrier), the bus is interfered, or the FF cable is damaged / poorly wired, which greatly limits the promotion and application of FF fieldbus.

[0009] The existing bus redundancy topology is as follows: Figure 2 As shown, the bus topology is a ring network topology, and AFD is a bus junction box. The AFD of this solution is required to be an intelligent device that can detect the fault conditions of the two ring network ports: 1. When a ring network port fails, its internal terminal resistor is enabled to ensure that the ring network becomes a physically independent bus and can be used normally; 2. When both ring network ports are fault-free, the internal terminal resistor is not enabled to ensure that only the two terminal resistors on the PA link are enabled in the entire ring network.

[0010] The Siemens solution is a typical ring network structure. The disadvantage of this structure is that it can only allow one fault point. If two fault points appear in the ring network, some instruments or even the entire bus instrument will be lost. Summary of the invention

[0011] The invention mainly solves the problem of lack of FF bus redundancy topology in the prior art and provides a Foundation Fieldbus redundancy method and device.

[0012] The above technical problems of the present invention are mainly solved by the following technical solutions: A Foundation Fieldbus redundancy method, comprising the following steps: each FF interface module generates and initially modulates a message and sends it to the FF redundant bus; the Y-type FF segment protector receives all the messages and selects one of the messages for decoding according to the negotiation mechanism, and then performs secondary modulation, and sends the secondary modulated message to the downstream instrument. Multiple FF interface modules and multiple FF redundant buses are set, each FF redundant bus operates independently and is wired separately, so as to improve the reliability of FF communication. When one FF bus has multiple fault points, the other bus is completely unaffected, and the overall FF communication can be guaranteed to be normal.

[0013] Preferably, the downstream instrument provides signal feedback after receiving the message; the Y-type FF segment protector is provided with the same number of CPUs as the FF interface modules, and each CPU receives the signal fed back by the downstream instrument; after the CPU parses the feedback signal, it sends the parsed signal to the FF redundant bus; the FF interface module receives the parsed signal transmitted by the FF redundant bus.

[0014] Preferably, the FF redundant bus is provided with buses having the same number as the FF interface modules.

[0015] Preferably, the FF interface module selects a parsing signal transmitted by one of the buses according to a decision mechanism.

[0016] Preferably, the negotiation mechanism is: setting a priority stack and a secondary stack, the selection right of the priority stack is higher than the selection right of the secondary stack, and within the same stack, message selection is performed according to the first-in-first-out principle.

[0017] Preferably, the decision-making mechanism is: selecting the analysis signal according to a first-come, first-served rule.

[0018] The present invention also provides a Foundation fieldbus redundancy device, comprising: a plurality of FF interface modules for generating and performing primary modulation messages; an FF redundant bus connected to the FF interface modules and performing message transmission; a Y-type FF segment protector connected to the FF redundant bus and performing secondary message modulation; and a downstream instrument for receiving messages and performing signal feedback.

[0019] Preferably, the Y-type FF segment protector is provided with CPUs having the same number as the FF interface modules.

[0020] Preferably, the FF redundant bus is provided with buses having the same number as the FF interface modules.

[0021] The beneficial effects of the present invention are: by setting up multiple FF interface modules and multiple FF redundant buses, each FF redundant bus operates independently and has separate wiring, thereby improving the reliability of FF communication. When one FF bus has multiple fault points, the other bus is completely unaffected, and the overall FF communication can be guaranteed to be normal. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of bus redundancy of the present invention.

[0023] Figure 2 It is a schematic diagram of Siemens PA bus ring network redundancy in the prior art.

[0024] In the figure, 1, the first FF interface module, 2, the second FF interface module, 3, the processing chip, 4, the MAC chip, 5, the first receiving module, 6, the first sending module, 7, the second sending module, 8, the power distribution module, 9, the power distribution modulation module, 10, the terminal, 11, the bus B, 12, the bus A, 13, the second receiving module, 14, the third sending module, 15, the first CPU, 16, the second CPU, 17, the third receiving module, 18, the fourth sending module, 19, the downstream instrument, and 20, the base. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0026] It should be noted that in the following description, reference is made to the accompanying drawings, which describe several embodiments of the present invention. It should be understood that other embodiments may also be used, and that mechanical composition, structure, electrical and operational changes may be made without departing from the spirit and scope of the present invention. The following detailed description should not be considered restrictive, and the scope of the embodiments of the present invention is limited only by the claims of the published patents. The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. Spatially related terms, such as "upper", "lower", "left", "right", "below", "below", "lower", "above", "upper", etc., may be used in the text to facilitate the description of the relationship between an element or feature shown in the figure and another element or feature.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix", "hold" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] Furthermore, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "comprises" and "includes" indicate the presence of the described features, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence or addition of one or more other features, operations, elements, components, items, kinds, and / or groups. It should be further understood that the terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Therefore, "A, B or C" or "A, B and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B and C". Exceptions to this definition occur only when a combination of elements, functions, or operations are inherently mutually exclusive in some manner.

[0029] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the technical solution in the embodiments of the present invention is further described in detail through the following embodiments and in combination with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the invention.

[0030] Embodiment: A Foundation fieldbus redundancy device comprises a plurality of FF interface modules for generating and performing primary modulation messages; an FF redundant bus connected to the FF interface modules and performing message transmission; a Y-type FF segment protector connected to the FF redundant bus and performing secondary message modulation, and a downstream instrument for receiving messages and performing signal feedback, wherein the Y-type FF segment protector is provided with the same number of CPUs as the FF interface modules, and the FF redundant bus is provided with the same number of buses as the FF interface modules; the FF interface modules of the present invention can be configured redundantly or as a single module; the present invention takes two redundantly configured FF interface modules as an example to illustrate an embodiment, such as Figure 1 As shown, it includes a first FF interface module 1, a second FF interface module 2, a bus A12, a bus B11, a power regulator, a base 20, a Y-type FF segment protector and a downstream instrument 19. The first FF interface module, the second FF interface module and the Y-type FF segment protector are respectively connected to the bus A and the bus B. The power regulator is installed in the base, the first FF interface module and the second FF interface module are installed on the base, and the power regulator supplies power to the devices connected to the bus A and the bus B.

[0031] The power supply regulator includes a power distribution modulation module 9 and a terminal 10. The terminal is used to adjust and display the power supply status. The power distribution modulation module is connected to the terminal and bus A or bus B respectively.

[0032] The first FF interface module and the second FF interface module both include a processing chip 3, a MAC chip 4, a first receiving module 5, a first sending module 6, a second sending module 7 and a power distribution module 8. The power distribution module is used to provide a power supply voltage. The processing chip is used to generate messages. The MAC chip is connected to the processing chip and is used to modulate the messages. The modulated messages are transmitted to bus B through the first sending module. The modulated messages are transmitted to bus A through the second sending module. The feedback signals on bus A and bus B are transmitted to the MAC chip through the first receiving module and are transmitted to the processing chip after being modulated by the MAC chip.

[0033] The Y-type FF network segment protector is installed in the junction box, powered by bus A and bus B, and can be expanded and cascaded. The Y-type FF network segment protector includes a first CPU 15, a second CPU 16, and a second receiving module 13, a third receiving module 17, a third sending module 14 and a fourth sending module 18 respectively connected to the first CPU and the second CPU. The first CPU and the second CPU receive the message of bus A or bus B through the second receiving module, and the first CPU and the second CPU send a feedback signal to bus A or bus B through the third sending module. The first CPU and the second CPU receive the feedback signal of the downstream instrument through the third receiving module, and the first CPU and the second CPU send the message to the downstream instrument through the fourth sending module.

[0034] The present invention also provides a Foundation Fieldbus redundancy method, comprising the following steps:

[0035] Each FF interface module generates and modulates the message for the first time and sends it to the FF redundant bus;

[0036] The Y-type FF segment protector receives all messages and selects one of the messages for decoding according to the negotiation mechanism, performs secondary modulation, and sends the secondary modulated message to the downstream instrument;

[0037] The downstream instrument will provide signal feedback after receiving the message;

[0038] The Y-type FF segment protector is equipped with the same number of CPUs as the FF interface modules, and each CPU receives the signal fed back by the downstream instrument;

[0039] After the CPU analyzes the feedback signal, it sends the analysis signal to the FF redundant bus;

[0040] The FF interface module receives the analysis signal transmitted by the FF redundant bus;

[0041] The FF interface module selects the parsing signal transmitted by one of the buses according to the decision mechanism;

[0042] The negotiation mechanism is: set the priority stack and the secondary stack. The priority stack has a higher selection right than the secondary stack. Within the same stack, messages are selected based on the first-in, first-out principle.

[0043] The decision-making mechanism is: the analysis signal is selected according to the first-come-first-served rule.

[0044] The bus redundancy method of the present invention is described in detail below with reference to two FF interface modules:

[0045] When the FF interface module sends message data, the processing chip generates a message to be sent to the MAC chip, and the MAC chip modulates two packets of the same message data and sends them to bus A and bus B at the same time.

[0046] Both CPUs of the Y-type FF segment protector receive the message data packets sent by the FF interface module, and the two CPUs negotiate to decide which CPU will re-modulate the message data packets and send them to the downstream instrument.

[0047] The negotiation mechanism is: put the first CPU and the second CPU into the priority stack, with the first CPU on top and the second CPU on the bottom. The message data packet is decoded and modulated by the first CPU and sent to the downstream instrument. When a decoding error occurs in the first CPU, the first CPU is put into the secondary stack. When the second message data packet arrives, since the second CPU is still in the priority stack, it is decoded and modulated by the second CPU and sent to the downstream instrument. When a decoding error also occurs in the second CPU, the second CPU is put into the secondary stack. Since the first CPU enters first, the first CPU will have priority in decoding and modulation next time. At this time, there is no CPU in the priority stack, so the priority stack will be placed at a lower level and its priority will be lowered to the back of the secondary stack, and this cycle will repeat.

[0048] After receiving the message data packet, the downstream instrument feeds back the corresponding message B according to the protocol. The two CPUs of the Y-type FF segment protector parse message B at the same time and send it to bus A and bus B at the same time.

[0049] After the first FF interface module and the second FF interface module receive messages from bus A and bus B, the processing chip decides to use message B from bus A or bus B through a decision-making mechanism. The decision-making mechanism is: when message B from bus A arrives first and is normal, message B transmitted by bus A is used; if message B transmitted by bus B arrives first and is normal, message B transmitted by bus B is used; if message B from bus A that arrives first is abnormal, message B from bus B is used.

[0050] Based on the setting of the bus redundancy device of the present invention, the faults on the redundant bus are divided into: 1) single FF interface module level fault; 2) single sending / receiving circuit fault of the FF interface module; 2) single FF bus fault; 3) single FF power regulator fault; 4) Y-type FF segment protector trunk fault; 2 or more fault points appear on the above single-side FF bus without affecting the normal operation of the bus; the Y-type FF segment protector can correct the FF signal and control the signal flow through the MCU, which can filter the interference of the trunk, ensure the integrity of the branch signal, and greatly improve the anti-interference performance of the bus.

[0051] The FF redundant bus provided by the present invention operates independently, and the two buses are wired separately, thereby improving the reliability of FF communication; when one FF bus has multiple fault points, the other bus is completely unaffected, thereby ensuring the normal communication of the entire FF; the FF interface module can transform the existing 2-segment module into a single-segment redundant module, and only requires upgrading the embedded firmware program, thereby reducing the development cost.

[0052] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A Foundation Fieldbus redundancy method, characterized in that: The following steps are involved: Each FF interface module generates and modulates the message for the first time and sends it to the FF redundant bus; The Y-type FF segment protector receives all messages and selects one of the messages for decoding according to the negotiation mechanism, performs secondary modulation, and sends the secondary modulated message to the downstream instrument; The Y-type FF network segment protector is provided with the same number of CPUs as the FF interface modules, and each CPU receives the signal fed back by the downstream instrument; each FF interface module includes the same number of sending modules as the FF interface modules; each CPU corresponds to an FF redundant bus, and each FF redundant bus corresponds to a sending module in the FF interface module; The negotiation mechanism is: setting a priority stack and a secondary stack, the selection right of the priority stack is higher than the selection right of the secondary stack, and within the same stack, message selection is performed according to the first-in-first-out principle.

2. A Foundation Fieldbus redundancy method according to claim 1, characterized in that: The downstream instrument will provide signal feedback after receiving the message; After the CPU analyzes the feedback signal, it sends the analysis signal to the FF redundant bus; The FF interface module receives the analysis signal transmitted by the FF redundant bus.

3. A Foundation Fieldbus redundancy method according to claim 2, characterized in that: The FF redundant bus is provided with buses having the same number as the FF interface modules.

4. A Foundation Fieldbus redundancy method according to claim 3, characterized in that: The FF interface module selects a parsing signal transmitted by one of the buses according to a decision mechanism.

5. A Foundation Fieldbus redundancy method according to claim 4, characterized in that: The decision-making mechanism is: selecting the analysis signal according to the first-come-first-served rule.

6. A Foundation Fieldbus redundancy device, characterized in that: include: Multiple FF interface modules for generating and performing primary modulation messages; FF redundant bus connected to the FF interface module and performing message transmission; Y-type FF segment protector connected to the FF redundant bus and performing secondary message modulation; The Y-type FF network segment protector is provided with the same number of CPUs as the FF interface modules, and each CPU receives the signal fed back by the downstream instrument; each FF interface module includes the same number of sending modules as the FF interface modules; each CPU corresponds to an FF redundant bus, and each FF redundant bus corresponds to a sending module in the FF interface module; And downstream instruments for receiving messages and providing signal feedback.

7. The FOUNDATION Fieldbus redundancy device according to claim 6, characterized in that: The Y-type FF network segment protector is provided with CPUs having the same number as the FF interface modules.

8. The FOUNDATION Fieldbus redundancy device according to claim 6, characterized in that: The FF redundant bus is provided with buses having the same number as the FF interface modules.

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