CN112260760B - Nuclear power plant distributed control system field bus system based on optical loop - Google Patents
Nuclear power plant distributed control system field bus system based on optical loop Download PDFInfo
- Publication number
- CN112260760B CN112260760B CN202011119654.8A CN202011119654A CN112260760B CN 112260760 B CN112260760 B CN 112260760B CN 202011119654 A CN202011119654 A CN 202011119654A CN 112260760 B CN112260760 B CN 112260760B
- Authority
- CN
- China
- Prior art keywords
- optical
- node
- ring network
- equipment
- bus
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/27—Arrangements for networking
- H04B10/275—Ring-type networks
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/03—Arrangements for fault recovery
- H04B10/038—Arrangements for fault recovery using bypasses
Abstract
The invention discloses a nuclear power plant distributed control system field bus system based on an optical loop, which comprises a plurality of node devices, a plurality of optical bypass modules and an optical fiber loop, wherein the node devices are all connected into the optical fiber loop through the optical bypass modules in an all-optical loop network connection mode; the optical bypass module ring network interface TX end corresponding to each node device is connected with the optical bypass module ring network interface RX end corresponding to the next node device through single mode optical fibers, bus link connection is sequentially achieved, the optical bypass module ring network interface TX end corresponding to the last node device is connected with the optical bypass module ring network interface RX end corresponding to the first node device, and therefore the optical ring network topological structure is formed. The invention utilizes node equipment to generate optical signals, and generates two paths of optical signals with the same data information through an optical bypass module, one path of optical signals is received and transmitted by a node, the other path of optical signals is transmitted in an optical ring, and a multi-node polling communication mode is combined to realize the method of the all-optical-path ring network topological structure with low power consumption and high reliability.
Description
Technical Field
The invention relates to the technical field of instrument control devices of distributed control systems of nuclear power plants, in particular to a field bus system of a distributed control system of a nuclear power plant based on an optical loop.
Background
In a digital instrument control system in the nuclear power field, the development and the progress of a network technology enable a digital communication technology to be well applied in the nuclear power field, wherein a field bus communication technology is used as a base layer network, and the field bus communication technology is an open type novel full-distributed control system. The method is widely applied to systems such as reactor core neutron flux measurement, rod control rod position, valve control, DCS network communication and the like. Fieldbus technology is commonly used as a communication platform with simple protocols, high fault tolerance, relatively high noise rejection, relatively high transmission rates, and wide common mode range. Meanwhile, the field bus control circuit has the advantages of convenience in control, low cost and the like. At present, more than 40 field buses exist internationally, the field buses are composed of 8 types, network topologies are bus type, tree type, star type and the like, and physical media are twisted-pair lines and optical fibers. However, in the past, a nuclear power instrument control field bus communication module utilizes low-voltage differential electric signals to transmit data streams, the influence of cable distribution parameters on the loss of the electric signals causes low remote communication speed, limited transmission bandwidth, poor anti-electromagnetic interference capability and incapability of expanding data throughput, so that the traditional field bus module can only transmit limited data volume in short distance, and meanwhile, the problem that a communication node bus line is paralyzed due to short circuit faults of a differential bus circuit is solved, and the traditional field bus can not well meet the high-reliability communication requirement of a nuclear power plant DCS platform. At present, a method for improving remote disturbance resistance is to convert a bus link electrical signal into an optical signal through a photoelectric conversion module and transmit the optical signal on an optical fiber cable, so that the expansion of a communication distance is realized, but a bus communication fault is caused by a node circuit short-circuit fault, and the communication of a bus link is interrupted; meanwhile, the conversion of the electro-optical signal under the long-distance communication realized by the optical signal can generate data transmission and forwarding delay, and the real-time performance of the field bus communication is influenced.
Disclosure of Invention
The technical problem to be solved by the invention is that the traditional field bus utilizes a photoelectric conversion module, only realizes the expansion of the transmission distance between nodes and improves the anti-interference performance, but still uses a differential cable to realize the bus connection of the nodes on a bus link in short-distance transmission. The node equipment is hung on a bus cable to realize access to a bus link, and the discontinuity of the impedance of the access point is an important reason for data signal reflection and is easily subjected to transient interference such as lightning surge of an external field; secondly, when the nodes are connected through the photoelectric conversion module in the long-distance transmission process, the forwarding delay of bus signals and the failure rate of a hardware circuit can be increased, and the real-time performance and the reliability of a bus link are influenced.
The invention aims to provide a nuclear power plant distributed control system field bus system based on an optical loop, and aims to overcome the defects of the existing field bus communication link.
The invention is realized by the following technical scheme:
a nuclear power plant distributed control system field bus system based on an optical loop comprises a plurality of node devices, optical bypass modules and an optical fiber loop, wherein each node device is correspondingly connected with one optical bypass module in an all-optical-path ring network connection mode, and the node devices are all connected into the optical fiber loop through the optical bypass modules; each node device TX end is connected with the TX end of the corresponding optical bypass module, and each node device RX receiving end is connected with the RX end of the corresponding optical bypass module; the optical bypass module ring network interface TX end corresponding to each node device is connected with the optical bypass module ring network interface RX end corresponding to the next node device through a single mode fiber, bus link connection is sequentially achieved, the optical bypass module ring network interface TX end corresponding to the last node device is connected with the optical bypass module ring network interface RX end corresponding to the first node device, the head node device and the tail node device are connected with the bus link through fiber jumpers, all-optical-path ring network bus link is achieved by the plurality of node devices, and therefore the optical ring network topological structure is formed;
each node device TX end serves as a sending end, and each node device RX end serves as a receiving end; the whole field bus link adopts an all-optical-path ring network topological structure;
the node equipment is used for completing a photoelectric conversion function and a protocol conversion function, converting information to be transmitted by the equipment into optical signals and converting the received optical signals into electric signals; meanwhile, the analysis function of the custom field bus protocol is realized and the custom field bus protocol is used as a bus controller;
the optical bypass module is used for completing the functions of accessing the node equipment into an optical fiber loop, forwarding optical ring network signals without delay, automatic link bypass of node equipment circuit failure and the like;
and generating optical signals by using the node equipment, generating two paths of optical signals with the same data information through the optical bypass module, wherein one path of optical signals is used for receiving and transmitting the nodes, and the other path of optical signals is transmitted in an optical loop, so that the all-optical-path ring network topological structure is realized.
The working principle is as follows:
the traditional field bus utilizes a photoelectric conversion module, only realizes the expansion of transmission distance between nodes and improves the anti-interference performance, but still uses a differential cable to realize the bus connection of the nodes on a bus link in short-distance transmission. The node equipment is hung on a bus cable to realize access to a bus link, and the discontinuity of the impedance of the access point is an important reason for data signal reflection and is easily subjected to transient interference such as lightning surge of an external field; secondly, when the nodes are connected through the photoelectric conversion module in the long-distance transmission process, the forwarding delay of bus signals and the failure rate of a hardware circuit can be increased, and the real-time performance and the reliability of a bus link are influenced.
The invention designs a nuclear power plant distributed control system field bus system based on an optical loop, which comprises a plurality of node devices, optical bypass modules and an optical fiber loop, wherein each node device is correspondingly connected with one optical bypass module in an all-optical-path ring network connection mode, and the node devices are all connected into the optical fiber loop through the optical bypass modules; optical cable transmission is adopted in design, and a single-mode optical fiber jumper and each node device are hung on a bus through an optical bypass module to form an all-optical-path ring network; the technical scheme of the invention has the advantages that the node hardware design is matched with a self-defined communication link protocol, meanwhile, bus link nodes form an access optical fiber ring network through a passive device and an optical cable, complete electrical isolation is realized with peripheral equipment, and transient interference such as lightning surge and the like does not have any interference on the all-optical path bus link, so that the bus topological structure has strong anti-interference capability, low power consumption, high communication speed and excellent confidentiality and safety performance.
Further, the optical bypass module comprises an optical fiber coupler and an optical switch, wherein the optical fiber coupler is correspondingly connected with the optical switch through an optical fiber jumper; in order to enable the node equipment to form an all-optical-path ring network structure through optical fibers, the optical bypass module integrates an optical fiber coupler, so that signal transmission between nodes directly sends optical signals to the ring network, or directly receives the optical signals from the ring network for response, signal conversion and distribution are not needed through the photoelectric conversion module, and the delay problem of optical path signals is solved.
The optical bypass module realizes the topological structure link of the all-optical-path ring network among the node devices, and each node device sends and receives the ring network access interface TX or RX of the access module respectively. The return loss of each interface of the optical fiber coupler reaches more than 50dB, and the transmission optical path is not influenced, so that the all-optical-path looped network link can be realized. Meanwhile, in order to prevent the optical path looped network occupation caused by the abnormal fault of the node equipment circuit, the optical switch switching function is used for realizing the optical transceiving signal bypass of the node equipment when the node equipment is abnormal, and the fault node is separated from the bus link.
The optical fiber coupler adopting the optical switch and the optical waveguide structure has the advantages of wide working temperature range, high ageing resistance, low insertion loss, no return loss caused by any reflecting end face, and switch switching service life of 107More than hours and the like.
Because the optical fiber coupler can generate-4 dB loss on the light splitting of optical signals, the number of ring network link nodes can be properly increased by reasonably setting the output power of an optical module accessed to the node equipment.
Furthermore, the optical fiber coupler adopts a 2 x 2 type optical fiber coupler, the working wavelength of the optical fiber coupler is 1260 nm-1650 nm, the insertion loss is 3.9dB, and the return loss is 50 dB.
Further, the entrance and exit loss of the optical switch is 0.6dB, and the switching speed is 8 ms.
Further, the node device comprises a control circuit, a photoelectric conversion circuit, a low-speed optical module and a power management unit, wherein the control circuit is externally connected with a device interface, the control circuit is connected with the photoelectric conversion circuit, and the photoelectric conversion circuit is connected with the low-speed optical module;
the low-speed optical module has an optical signal output power adjusting function and is used for adjusting optical power according to the number of node equipment accessed to the optical path ring network; the optical fiber is not influenced by the distribution parameters of the cable on signals, has the characteristics of loss lower than 0.2dB/km, no electromagnetic pulse interference and high security and confidentiality, and is the best choice for transmitting data by field equipment of a nuclear instrument control platform.
The photoelectric conversion circuit is used for converting optical signals on an optical path bus (namely on the optical bypass module and the optical fiber loop) and the electric signals of the control circuit; meanwhile, a receiving port RX of the low-speed optical module is provided with an optical power detection output interface, and the interface transmits an optical channel intensity signal to a control circuit. When the optical path is occupied by other node equipment, the optical power detection interface outputs high level, and the control circuit enables the node equipment to enter a waiting mode; when the optical path bus is in an idle state, the optical power detection interface outputs a low level, and the control circuit enables the node equipment to enter a sending mode.
The control circuit is used for completing the conversion of the link serial-parallel bit stream data, the data sending and caching, and the receiving and filtering self-defined bus link communication protocol for analysis. In order to avoid the situation that a plurality of devices occupy an optical path simultaneously to cause optical path signal congestion and data confusion, the design adopts a single-master multi-slave mode to realize polling inquiry processing and carry out data communication between the master device and the plurality of slave devices.
And the power supply management unit is used for supplying power to each module in the node equipment.
Further, the self-defined bus link communication protocol processes bus communication, and data communication between the master node device and the plurality of slave node devices is performed by using mechanisms such as polling, collision detection and automatic arbitration;
the node equipment is matched with the custom bus link communication protocol to complete the designed field bus, and the node equipment adopts a broadcast or unicast mode to establish communication with other equipment; the all-optical-path field bus supports the function of multiple main node devices, wherein one node device is configured as a main device node, and the rest node devices are configured as slave device nodes; and finishing the communication of the bus link through the corresponding custom communication protocol of the master and slave equipment nodes.
The corresponding custom communication protocol flow of the master and slave equipment nodes is as follows:
(1) the master node can only send requests when in an "idle" state; after sending a request, the node leaves the idle state, waits for the end of the response processing, and cannot send a second request; when a unicast request is sent to a slave node, the master node enters a 'waiting for response' state, and a critical timeout is started, wherein the timeout is called 'response timeout'; when receiving a response, the main equipment node checks the response before processing the data, and completes the response processing after the correct check; the master device node enters an error processing state, and then the error processing is finished;
(2) when the slave equipment node is in an idle state, receiving a request sent from the master equipment node, checking the request, processing a request action after checking the request is correct, and sending response data; when a check error or a request error occurs, the slave node enters an error "processing state", and must send a response to the master node, after which the error processing is ended.
Furthermore, the speed of the low-speed optical module is DC-30 Mbps, and the speed requirement of a field bus is met.
Furthermore, the optical fiber loop adopts a single mode optical fiber, and the single mode optical fiber utilizes the characteristic that the single mode optical fiber propagates one mode under the appointed wavelength, so that the intermodal dispersion is very small, the long-distance transmission is realized, and the transmission distance can generally reach more than 15 Km.
The whole field bus link adopts an all-optical-path ring network topological structure, and the problems of cable signal reflection, namely impedance discontinuity and impedance mismatching of bus transmission and the like do not need to be considered; the problem of the installation configuration of the terminal resistor and the bias resistor is solved, so that the engineering construction is simplified, and the operation is convenient. Meanwhile, the problems of undisturbed bypass of node short circuit fault, photoelectric signal forwarding delay and the like are solved. The construction of a field device network of a distributed control system of a nuclear power plant is met.
Compared with the prior art, the invention has the following advantages and beneficial effects:
1. the invention designs a nuclear power plant distributed control system field bus system based on an optical loop, which comprises a plurality of node devices, optical bypass modules and an optical fiber loop, wherein each node device is correspondingly connected with one optical bypass module in an all-optical-path ring network connection mode, and the node devices are all connected into the optical fiber loop through the optical bypass modules; each node device consists of an optical bypass module, a low-speed optical module and a control circuit; the design adopts optical cable transmission, and the single mode fiber jumper and each node device are hung on the bus through the optical bypass module to form an all-optical-path ring network.
2. The technical scheme of the invention has the advantages that the node hardware design is matched with a self-defined communication link protocol, meanwhile, bus link nodes form an access optical fiber ring network through a passive device and an optical cable, complete electrical isolation is realized with peripheral equipment, and transient interference such as lightning surge and the like does not have any interference on the all-optical path bus link, so that the bus topological structure has strong anti-interference capability, low power consumption, high communication speed and excellent confidentiality and safety performance.
3. The invention relates to an architecture design based on a nuclear power station instrument control communication field bus, which utilizes node equipment to generate optical signals, generates two paths of optical signals with the same data information through an optical bypass module, receives and transmits one path of optical signals through a node, transmits the other path of optical signals in an optical loop, and combines a multi-node polling communication mode to realize a method of an all-optical-path ring network topological structure with low power consumption and high reliability. The method is simple, meets the requirement of system safety isolation, has few peripheral devices and is easy to realize.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:
fig. 1 is a schematic diagram of an all-optical-path ring network link architecture of a nuclear power plant distributed control system field bus system based on an optical ring.
Fig. 2 is a diagram of the optical bypass module architecture according to the present invention.
Fig. 3 is a hardware architecture diagram of the node device of the present invention.
FIG. 4 is a state diagram of a master node according to the present invention.
FIG. 5 is a slave node state diagram of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that: it is not necessary to employ these specific details to practice the present invention. In other instances, well-known structures, circuits, materials, or methods have not been described in detail so as not to obscure the present invention.
Throughout the specification, reference to "one embodiment," "an embodiment," "one example," or "an example" means: the particular features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment of the invention. Thus, the appearances of the phrases "one embodiment," "an embodiment," "one example" or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combination and/or sub-combination in one or more embodiments or examples. Further, those of ordinary skill in the art will appreciate that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
In the description of the present invention, it is to be understood that the terms "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "high", "low", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and therefore, are not to be construed as limiting the scope of the present invention.
Example 1
As shown in fig. 1 to 5, the invention relates to a nuclear power plant distributed control system field bus system based on an optical loop, which comprises a plurality of node devices, optical bypass modules and an optical fiber loop, wherein each node device is correspondingly connected with one optical bypass module, and adopts an all-optical-path ring network connection mode, and the node devices are all connected into the optical fiber loop through the optical bypass modules; each node device TX end is connected with the TX end of the corresponding optical bypass module, and each node device RX receiving end is connected with the RX end of the corresponding optical bypass module; the optical bypass module ring network interface TX end corresponding to each node device is connected with the optical bypass module ring network interface RX end corresponding to the next node device through single mode optical fibers, bus link connection is sequentially achieved, the optical bypass module ring network interface TX end corresponding to the last node device is connected with the optical bypass module ring network interface RX end corresponding to the first node device, and therefore an optical ring network topological structure is formed;
the node equipment is used for completing a photoelectric conversion function and a protocol conversion function, converting information to be transmitted by the equipment into optical signals and converting the received optical signals into electric signals; meanwhile, the analysis function of the custom field bus protocol is realized and the custom field bus protocol is used as a bus controller;
the optical bypass module is used for completing the functions of accessing the node equipment into an optical fiber loop, forwarding optical ring network signals without delay, automatic link bypass of node equipment circuit failure and the like;
and generating optical signals by using the node equipment, generating two paths of optical signals with the same data information through the optical bypass module, wherein one path of optical signals is used for receiving and transmitting the nodes, and the other path of optical signals is transmitted in an optical loop, so that the all-optical-path ring network topological structure is realized.
In this embodiment, the optical bypass module includes an optical fiber coupler and an optical switch, and the optical fiber coupler is correspondingly connected to the optical switch through an optical fiber jumper; in order to enable the node equipment to form an all-optical-path ring network structure through optical fibers, the optical bypass module integrates an optical fiber coupler, so that signal transmission between nodes directly sends optical signals to the ring network, or directly receives the optical signals from the ring network for response, signal conversion and distribution are not needed through the photoelectric conversion module, and the delay problem of optical path signals is solved. The block diagram of the optical bypass module architecture is shown in fig. 2.
The optical bypass module realizes the topological structure link of the all-optical-path ring network among the node devices, and each node device sends and receives the ring network access interface TX or RX of the access module respectively. The return loss of each interface of the optical fiber coupler reaches more than 50dB, and the transmission optical path is not influenced, so that the all-optical-path looped network link can be realized. Meanwhile, in order to prevent the optical path looped network occupation caused by the abnormal fault of the node equipment circuit, the optical switch switching function is used for realizing the optical transceiving signal bypass of the node equipment when the node equipment is abnormal, and the fault node is separated from the bus link.
The optical fiber coupler adopting the optical switch and the optical waveguide structure has the advantages of wide working temperature range, high ageing resistance, low insertion loss, no return loss caused by any reflecting end face, and switch switching service life of 107More than hours and the like.
Because the optical fiber coupler can generate-4 dB loss on the light splitting of optical signals, the number of ring network link nodes can be properly increased by reasonably setting the output power of an optical module accessed to the node equipment.
In this embodiment, the optical fiber coupler is a 2 × 2 type optical fiber coupler, and has a working wavelength of 1260nm to 1650nm, an insertion loss of 3.9dB, and a return loss of 50 dB. The optical switch has an access loss of 0.6dB and a switching speed of 8 ms.
In this embodiment, the optical fiber loop employs a single mode optical fiber, and the single mode optical fiber utilizes the characteristic that the single mode optical fiber propagates one mode at a specified wavelength, so that the intermodal dispersion is small, and long-distance transmission is realized, and the transmission distance can generally reach more than 15 Km.
When in implementation: the specific all-optical-path ring network topology structure is shown in fig. 1, the data transmission and reception of each node device is realized through a low-speed optical module of the node device, the minimum receiving optical power reaches-28 dBm, and the maximum transmitting optical power can be-8 dBm. The low-speed optical module adopts single-mode optical fiber for transmission, and the maximum speed effective transmission distance reaches more than 15 Km. The optical bypass module realizes that the node equipment is accessed into a topological structure of a full optical path ring network, a 2 multiplied by 2 type optical coupler built in the optical bypass module has the working wavelength of 1260 nm-1650 nm, the insertion loss of 3.9dB and the return loss of 50 dB; the optical switch has an access loss of 0.6dB and a switching speed of 8 ms.
The full optical path ring network connection mode is that a node equipment TX sending end is connected with a TX end of an optical bypass module, and a node equipment RX receiving end is connected with an RX end of the optical bypass module; the optical bypass module ring network interface TX end of each node device is connected with the next node optical bypass module ring network interface RX end through a single mode fiber to sequentially realize bus link connection, and the last node optical bypass module ring network interface TX end is connected with the first node optical bypass module ring network interface RX end to finally form an optical ring network topological structure. As shown in fig. 1 and 2.
The full optical path ring network topological structure refers to a daisy chain topological structure, and the head and tail nodes are connected into the bus link through the optical fiber jumper, so that the plurality of node devices form full optical path ring network bus link. The access optical bypass module of the whole optical fiber ring network link node completely uses optical devices and optical cables, and has strong anti-interference capability, low power consumption and excellent data safety performance.
The working principle is as follows: the invention designs a nuclear power plant distributed control system field bus system based on an optical loop, which comprises a plurality of node devices, optical bypass modules and an optical fiber loop, wherein each node device is correspondingly connected with one optical bypass module in an all-optical-path ring network connection mode, and the node devices are all connected into the optical fiber loop through the optical bypass modules; optical cable transmission is adopted in design, and a single-mode optical fiber jumper and each node device are hung on a bus through an optical bypass module to form an all-optical-path ring network; the technical scheme of the invention has the advantages that the node hardware design is matched with a self-defined communication link protocol, meanwhile, bus link nodes form an access optical fiber ring network through a passive device and an optical cable, complete electrical isolation is realized with peripheral equipment, and transient interference such as lightning surge and the like does not have any interference on the all-optical path bus link, so that the bus topological structure has strong anti-interference capability, low power consumption, high communication speed and excellent confidentiality and safety performance.
The invention relates to an architecture design based on a nuclear power station instrument control communication field bus, which is characterized in that node equipment is utilized to generate optical signals, two paths of optical signals with the same data information are generated through an optical bypass module, one path of optical signal is used for receiving and transmitting the node, the other path of optical signal is transmitted in an optical loop, and a method for realizing an all-optical-path ring network topological structure with low power consumption and high reliability can be realized by combining a multi-node polling communication mode. The method is simple, meets the requirement of system safety isolation, has few peripheral devices and is easy to realize.
Example 2
As shown in fig. 1 to 5, the present embodiment is different from embodiment 1 in that, as shown in fig. 3, fig. 3 is a hardware architecture diagram of a node device according to the present invention; the node equipment comprises a control circuit, a photoelectric conversion circuit, a low-speed optical module and a power management unit, wherein the control circuit is externally connected with an equipment interface, the control circuit is connected with the photoelectric conversion circuit, and the photoelectric conversion circuit is connected with the low-speed optical module;
the low-speed optical module has an optical signal output power adjusting function and is used for adjusting optical power according to the number of node equipment accessed to the optical path ring network; the optical fiber is not influenced by the distribution parameters of the cable on signals, has the characteristics of loss lower than 0.2dB/km, no electromagnetic pulse interference and high security and confidentiality, and is the best choice for transmitting data by field equipment of a nuclear instrument control platform.
The photoelectric conversion circuit is used for converting optical signals on an optical path bus (namely on the optical bypass module and the optical fiber loop) and the electric signals of the control circuit; meanwhile, a receiving port RX of the low-speed optical module is provided with an optical power detection output interface, and the interface transmits an optical channel intensity signal to a control circuit. When the optical path is occupied by other node equipment, the optical power detection interface outputs high level, and the control circuit enables the node equipment to enter a waiting mode; when the optical path bus is in an idle state, the optical power detection interface outputs a low level, and the control circuit enables the node equipment to enter a sending mode.
The control circuit is used for completing the conversion of the link serial-parallel bit stream data, the data sending and caching, and the receiving and filtering self-defined bus link communication protocol for analysis. In order to avoid the situation that a plurality of devices occupy an optical path simultaneously to cause optical path signal congestion and data confusion, the design adopts a single-master multi-slave mode to realize polling inquiry processing and carry out data communication between the master device and the plurality of slave devices.
And the power supply management unit is used for supplying power to each module in the node equipment.
Example 3
As shown in fig. 1 to fig. 5, the difference between this embodiment and embodiment 1 is that, in the process of receiving and transmitting data in a multi-node communication link, a low-speed optical module receiving port detects an output interface according to optical path power, an optical module of each node device detects an optical path signal, when an optical path is occupied by other node devices, an optical power detection interface of the node device outputs a high level, and the device enters a waiting mode; when the optical path is in an idle state, the optical power detection interface of the node device outputs a low level, and the device enters a sending mode. In order to avoid light path signal congestion and data confusion caused by the fact that a plurality of devices occupy light paths at the same time, a user-defined bus link protocol is adopted for processing bus communication, and mechanisms such as polling, conflict detection and automatic arbitration are utilized for data communication between a plurality of master device nodes and a plurality of slave device nodes. The custom protocol is shown in fig. 4 and fig. 5, fig. 4 is a state diagram of a master device node of the present invention, and fig. 5 is a state diagram of a slave device node of the present invention.
The self-defined bus link communication protocol processes bus communication, and data communication between the master node equipment and the plurality of slave node equipment is carried out by utilizing mechanisms such as polling, conflict detection, automatic arbitration and the like;
the node equipment is matched with the custom bus link communication protocol to complete the designed field bus, and the node equipment adopts a broadcast or unicast mode to establish communication with other equipment; the all-optical-path field bus supports the function of multiple main node devices, wherein one node device is configured as a main device node, and the rest node devices are configured as slave device nodes; and finishing the communication of the bus link through the corresponding custom communication protocol of the master and slave equipment nodes.
The corresponding custom communication protocol flow of the master and slave equipment nodes is as follows:
(1) the master node can only send requests when in an "idle" state; after sending a request, the node leaves the idle state, waits for the end of the response processing, and cannot send a second request; when a unicast request is sent to a slave node, the master node enters a 'waiting for response' state, and a critical timeout is started, wherein the timeout is called 'response timeout'; when receiving a response, the main equipment node checks the response before processing the data, and completes the response processing after the correct check; the master device node enters an error processing state, and then the error processing is finished;
(2) when the slave equipment node is in an idle state, receiving a request sent from the master equipment node, checking the request, processing a request action after checking the request is correct, and sending response data; when a check error or a request error occurs, the slave node enters an error "processing state", and must send a response to the master node, after which the error processing is ended.
In this embodiment, the speed of the low-speed optical module is DC-30 Mbps, and the field bus speed requirement is met.
The whole field bus link adopts an all-optical-path ring network topological structure, and the problems of cable signal reflection, namely impedance discontinuity and impedance mismatching of bus transmission and the like do not need to be considered; the problem of the installation configuration of the terminal resistor and the bias resistor is solved, so that the engineering construction is simplified, and the operation is convenient. Meanwhile, the problems of undisturbed bypass of node short circuit fault, photoelectric signal forwarding delay and the like are solved. The construction of a field device network of a distributed control system of a nuclear power plant is met.
The invention relates to an architecture design based on a nuclear power station instrument control communication field bus, which is characterized in that node equipment is utilized to generate optical signals, an optical bypass module is utilized to generate two paths of optical signals with the same data information, one path of optical signal is used for receiving and transmitting nodes, the other path of optical signal is transmitted in an optical loop, and a multi-node polling communication mode is combined to realize a method for realizing an all-optical-path ring network topological structure with low power consumption and high reliability. The method is simple, meets the requirement of system safety isolation, has few peripheral devices and is easy to realize.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. A nuclear power plant distributed control system field bus system based on an optical loop is characterized by comprising a plurality of node devices, optical bypass modules and an optical fiber loop, wherein each node device is correspondingly connected with one optical bypass module in an all-optical-path ring network connection mode, and the node devices are all connected into the optical fiber loop through the optical bypass modules; each node device TX end is connected with the TX end of the corresponding optical bypass module, and each node device RX receiving end is connected with the RX end of the corresponding optical bypass module; the optical bypass module ring network interface TX end corresponding to each node device is connected with the optical bypass module ring network interface RX end corresponding to the next node device through single mode optical fibers, bus link connection is sequentially achieved, the optical bypass module ring network interface TX end corresponding to the last node device is connected with the optical bypass module ring network interface RX end corresponding to the first node device, and therefore an optical ring network topological structure is formed;
the node equipment is used for completing a photoelectric conversion function and a protocol conversion function, converting information to be transmitted by the equipment into optical signals and converting the received optical signals into electric signals; meanwhile, the analysis function of the custom field bus protocol is realized and the custom field bus protocol is used as a bus controller;
the optical bypass module is used for completing the functions of accessing the node equipment into an optical fiber loop, forwarding optical ring network signals without delay and automatically bypassing a link when the node equipment fails;
the node equipment is utilized to generate optical signals, the optical bypass module is utilized to generate two paths of optical signals with the same data information, one path of optical signal is used for receiving and transmitting nodes, and the other path of optical signal is transmitted in an optical loop, so that an all-optical-path ring network topological structure is realized;
the optical bypass module comprises an optical fiber coupler and an optical switch, and the optical fiber coupler is correspondingly connected with the optical switch through an optical fiber jumper; when the node equipment is abnormal, the optical switch switching function is used for realizing the bypass of the optical transmitting and receiving signals of the node equipment and stripping a fault node from a bus link;
the self-defined bus link communication protocol processes bus communication, and data communication between the master node equipment and the plurality of slave node equipment is carried out by utilizing polling, conflict detection and automatic arbitration mechanisms; the node equipment is matched with the self-defined bus link communication protocol to complete a field bus, and the node equipment adopts a broadcast or unicast mode to establish communication with other equipment; the all-optical-path field bus supports the function of multiple main node devices, wherein one node device is configured as a main device node, and the rest node devices are configured as slave device nodes; the communication of the bus link is completed through the corresponding self-defined communication protocol of the master device node and the slave device node;
the corresponding custom communication protocol flow of the master and slave equipment nodes is as follows:
the master node can only send requests when in an "idle" state; after sending a request, the node leaves the idle state, waits for the end of the response processing, and cannot send a second request; when a unicast request is sent to a slave node, the master node enters a 'waiting for response' state, and a critical timeout is started, wherein the timeout is called 'response timeout'; when receiving a response, the main equipment node checks the response before processing the data, and completes the response processing after the correct check; the master device node enters an error processing state, and then the error processing is finished;
when the slave equipment node is in an idle state, receiving a request sent from the master equipment node, checking the request, processing a request action after checking the request is correct, and sending response data; when a check error or a request error occurs, the slave node enters an error "processing state", and must send a response to the master node, after which the error processing is ended.
2. The optical ring loop-based nuclear power plant distributed control system fieldbus system of claim 1, wherein the fiber coupler is of an optical waveguide type structure.
3. The optical ring loop-based field bus system of the distributed control system of the nuclear power plant is characterized in that a 2 x 2 type optical fiber coupler is adopted as the optical fiber coupler, the working wavelength is 1260 nm-1650 nm, the insertion loss is 3.9dB, and the return loss is 50 dB.
4. An optical ring based optical power plant distributed control system fieldbus system as claimed in claim 1, in which the optical switch has an access loss of 0.6dB and a switching speed of 8 ms.
5. An optical ring loop-based nuclear power plant distributed control system field bus system as claimed in claim 1, wherein said node device comprises a control circuit, a photoelectric conversion circuit, a low speed optical module and a power management unit, said control circuit is externally connected with a device interface, said control circuit is connected with said photoelectric conversion circuit, said photoelectric conversion circuit is connected with the low speed optical module;
the low-speed optical module has an optical signal output power adjusting function and is used for adjusting optical power according to the number of node equipment accessed to the optical path ring network; the receiving port RX of the low-speed optical module is provided with an optical power detection output interface which transmits an optical channel intensity signal to a control circuit;
the photoelectric conversion circuit is used for converting optical signals on the optical path bus into electric signals of the control circuit;
the control circuit is used for completing the conversion of the serial-parallel bit stream data of the link, the sending and caching of the data, and the receiving and filtering of the custom bus link communication protocol for analysis;
and the power supply management unit is used for supplying power to each module in the node equipment.
6. An optical ring based nuclear power plant distributed control system fieldbus system as claimed in claim 5, in which the rate of the low-speed optical module is DC-30 Mbps.
7. An optical loop-based nuclear power plant distributed control system fieldbus system as claimed in claim 1, in which the optical loop employs a single-mode fiber, and the transmission distance of the single-mode fiber is 15Km or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011119654.8A CN112260760B (en) | 2020-10-19 | 2020-10-19 | Nuclear power plant distributed control system field bus system based on optical loop |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011119654.8A CN112260760B (en) | 2020-10-19 | 2020-10-19 | Nuclear power plant distributed control system field bus system based on optical loop |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112260760A CN112260760A (en) | 2021-01-22 |
| CN112260760B true CN112260760B (en) | 2022-01-11 |
Family
ID=74244944
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011119654.8A Active CN112260760B (en) | 2020-10-19 | 2020-10-19 | Nuclear power plant distributed control system field bus system based on optical loop |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112260760B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113452444A (en) * | 2021-06-28 | 2021-09-28 | 中国电信股份有限公司 | Optical module, communication device, and failure monitoring method |
| CN115603802B (en) * | 2022-11-30 | 2023-03-10 | 中国船舶集团有限公司第七〇七研究所 | Time-frequency reference equipment, fault positioning method thereof and optical fiber ring network recovery method |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6094600A (en) * | 1996-02-06 | 2000-07-25 | Fisher-Rosemount Systems, Inc. | System and method for managing a transaction database of records of changes to field device configurations |
| CN101677280B (en) * | 2008-09-17 | 2011-10-05 | 中国科学院自动化研究所 | Optical fiber field bus communication system |
| CN105162514B (en) * | 2015-09-24 | 2018-07-03 | 中国民用航空总局第二研究所 | Optical fiber ring network communication system and method |
| CN105240051B (en) * | 2015-10-10 | 2018-03-23 | 成都金自天正智能控制有限公司 | A kind of fieldbus mine TT＆C system |
| CN110955626A (en) * | 2019-11-26 | 2020-04-03 | 山东有人信息技术有限公司 | Method and system for realizing Modbus communication on serial link |
-
2020
- 2020-10-19 CN CN202011119654.8A patent/CN112260760B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112260760A (en) | 2021-01-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0224132B1 (en) | Optical composite transceiver | |
| CN112260760B (en) | Nuclear power plant distributed control system field bus system based on optical loop | |
| CN111654359B (en) | Hot standby redundant communication system and method | |
| CN104753597B (en) | A kind of passive fiber buss cut-in methods of light splitting RS 485 and system | |
| US8412041B2 (en) | Subscriber premises side optical network unit and optical transmission system | |
| CN112865880B (en) | System and method for one-way data transmission through optical port | |
| CN101582723A (en) | CAN bus physical layer structure based on 1XN passive optical splitter (POS) | |
| CN108063736A (en) | A kind of industrial ethernet switch that long-distance cable is supported to communicate and control method | |
| WO2019153333A1 (en) | Pon-can bus architecture and robot system | |
| CN203119899U (en) | RTU communication device and electric power transmission system | |
| CN104618020B (en) | A kind of passive fiber buss single port terminals of light splitting RS 485 | |
| CN207995092U (en) | Realize the optical communication equipment of optical port redundant link defencive function | |
| CN104753598B (en) | A kind of passive fiber buss communication means of light splitting RS 485 | |
| CN104753596B (en) | A kind of passive many mouthfuls of terminals of the fiber buss of light splitting RS 485 | |
| CN104579474A (en) | Passive optical splitter RS-485 optical fiber bus embedded terminal | |
| Cisco | Installation Preparation | |
| CN114039809A (en) | CAN remote communication system based on optical transceiver | |
| CN108833243B (en) | High-speed optical data bus based on passive optical bus technology | |
| CN113162683A (en) | Airborne FC communication link fault detection method | |
| CN208209956U (en) | Passive automatic light shunting device and its optical fiber telecommunications system | |
| CN219124214U (en) | CAN communication architecture based on time division multiplexing | |
| Lewis | Fiber optic data busses for aircraft | |
| CN207835474U (en) | A kind of quick half-duplex communication circuit | |
| Minowa et al. | Development of fiber-optic local area networks in Japan | |
| CN113840189A (en) | Vehicle CAN network fiber system based on passive optical network |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |