CN102866690A - Redundancy switching method among redundancy process control stations in distributed control system - Google Patents
Redundancy switching method among redundancy process control stations in distributed control system Download PDFInfo
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Abstract
The invention discloses a redundancy switching method among redundancy process control stations in a distributed control system, comprising the following steps of: implementing data synchronism among the redundancy process control stations via a redundancy network; respectively connecting each process control station and each engineer station to a switchboard via a network; sending heartbeat signals to the process control station in a standby state by the process control station in an activate state; setting up a system variable by the process control station; modifying the data of the system variable by the process control station in the activate state whenever executing a control logic; synchronizing the data of the system variable to the process control station in the standby state via a private network by the process control station in the activate state when synchronizing data to the process control station in the standby state; and judging whether the data of the variable in the synchronized data is the same with the last received one or not by the process control station in the standby state and judging whether the process control station in the standby state is activated. Through the method disclosed by the invention, the reliability of switching process control stations is improved.
Description
Technical field
The present invention relates to a kind of reliable implementation method that in scattered control system, between the redundancy process control station, redundancy is switched, specifically be applicable to switching realization between the redundancy process control station in all scattered control systems.
Background technology
Scattered control system (distribute control system, DCS) is a kind of new control system that integrates control technology, computer technology, the communication technology, network technology.It is characterized in that decentralised control and centralized management, the control task of complicated industrial process is distributed on several process control stations and completes, and realize concentrated supervision, operation and the management to whole production run by the communication between SCADA and each process control station.
Process control station is the CPU (central processing unit) of scattered control system (DCS), is the core component of DCS, is responsible for the computing of steering logic and the processing of input signal and output order, also needs the communication function between realization and SCADA simultaneously.
As process control station breaks down, will cause losing to the supervision of procedure parameter with to the control ability of technological process, the consequence that this may bringing on a disaster property, have therefore all carried out Redundancy Design to process control station.Only has a process control station during normal operation in " activation " state, the another one process control station is in " standby " state, when the process control station in " standby " state judges the process control station failure in " activation " state, it will be rapidly by self " activation ", thereby obtains the control to field apparatus.If the error in judgement situation occurs, can cause two process control stations all in " activation " state, will cause like this disturbance of field apparatus, bring uncertain consequence.On this basis, how to judge process control station in " activation " state whether true fault just become a gordian technique of native system, each DCS producer has all spent very large energy in this regard.At present main implementation method has several as follows:
1. hardware interlock technology, process control station in " activation " state sends a DO signal to the process control station in " standby " state, when the process control station in " activation " state breaks down, this DO Signal Fail, when the process control station in " standby " state monitors the DO Signal Fail, self is switched to " activation " state.Domestic DCS producer comes the redundancy switching between the implementation procedure control station more by the method, and shortcoming is to need hardware supported, has raised the hardware cost of process control station.
2. under the prerequisite that does not increase hardware cost, part DCS producer uses software instead and realizes interlock function, therefore for the redundancy process control station, data are synchronously necessary functions, all by a specialized network, carry out data between the redundancy process control station in substantially all DCS systems synchronous.Process control station in " activation " state in part DCS system transmits " heartbeat " signal to the process control station in " standby " state with this dedicated network, when this process control station monitors this " heartbeat " blackout, self is switched to " activation " state.The shortcoming of the method is when this dedicated network breaks down, and there will be two process control stations all in " activation " state.
3. for fear of the generation of above-mentioned situation, part DCS system has been made following modification, as shown in Figure 1, two process control stations and SCADA system all are connected on a public exchange by a network, in the case, if increasing a road " heartbeat " signal by this network, the process control station in " activation " state sends to the process control station in " standby " state, when so now the process control station in " standby " state must monitor two-way " heartbeat " blackout, self could be switched to " activation " state, the effective like this fault that can produce in the second method of having avoided.
But for the redundancy process control station, data are synchronously necessary functions, take turns before logic carries out in the process control station of " activation " state is every, all all whole variablees must be synchronized to the process control station in " standby " state by dedicated network, these variablees synchronously require a great deal of time, for common engineering, carry out the synchronous time that probably needs 80 milliseconds of costs of a secondary data, this will reduce the real-time of process control station.For process control station, real-time is that the execution cycle of process control station is also a very important index, the higher occasion at some requirement of real-time, more need to consider the performance of its real-time, on this basis, if transmit " heartbeat " signal with this dedicated network, the real-time of process control station will be reduced.
For the reliability of taking into account redundancy switching and real-time two aspects that do not reduce process control station, the present invention proposes reliability that a kind of software realizes that both implementation methods of combining of " heartbeat "+" data are synchronous " guarantee that redundancy is switched and the real-time of maintenance process control station.
Summary of the invention
Technical matters to be solved by this invention is to provide in a kind of scattered control system a kind of implementation method of redundancy switching between the redundancy process control station, and the reliability that guarantees the redundancy switching is the real-time of keep-process control station also.
For solving the problems of the technologies described above, the invention provides in a kind of scattered control system redundancy switching method between the redundancy process control station, it is characterized in that, comprise the following steps:
1) realize that by a dedicated network data are synchronous between the redundancy process control station;
2) engineer station or SCADA system are connected to switch by a network (physical form can be two kinds of electricity, light), and each process control station is connected with switch simultaneously;
3) the logical described network of the process control station in " activation " state sends first via heartbeat signal (a frame traffic message) to the process control station in " standby " state, sends the fixed cycle that the first via heartbeat signal cycle is defaulted as setting;
4) set up a system variable in each process control station;
5) revise described system variable data in steering logic of the every execution of the process control station of " activation " state, every variable data of taking turns adds 1;
6) process control station in " activation " state while sending to the process control station in " standby " state, comprises the second road heartbeat signal by every synchrodata of taking turns by network, and the data that are about to described system variable are also synchronously pass by;
7) the process control station receiving isochronous data in " standby " state also compares data and last receive whether identical of system variable in synchrodata, if it is not identical, show in the process control station of " activation " state working properlyly, be left intact;
8), if twice numerical value is identical, check whether the process control station first via heartbeat signal in " activation " state exists
;
9), if first via heartbeat signal disappears, the process control station in " standby " state is self " activation ", thereby obtains the control to field apparatus
,if first via heartbeat signal does not disappear, two-way heartbeat signal Jin You mono-tunnel fault is described, the while also shows in the process control station of " activation " state working properly, is left intact
.
Redundancy switching method between the redundancy process control station in aforesaid scattered control system, it is characterized in that: in described step 2) in, described switch is one or more, and direct-connected between each switch while being a plurality of when switch, each switch is connected with a process control station.
Redundancy switching method between the redundancy process control station in aforesaid scattered control system is characterized in that: in described step 3), the fixed cycle is 200 milliseconds.
The beneficial effect that the present invention reaches: the invention discloses a kind of reliable implementation method that in scattered control system, between the redundancy process control station, redundancy is switched, only pass through the condition of whether normally switching as redundancy of a road " heartbeat " signal between the redundancy process control station, can cause to a certain extent the process control station of two " activation " states to exist, can bring unpredictable consequence to process control like this.If transmit respectively " heartbeat " signal by two networks respectively can reduce to a certain extent the real-time performance of process control station, adopt the method applied in the present invention, the reliability that both can guarantee redundancy switching also can the keep-process control station real-time, and on software is realized also very simple.
The accompanying drawing explanation
The overall network Organization Chart that Fig. 1 is redundancy process control station of the present invention;
Fig. 2 is the structural representation that redundancy process control station Main Assistant Controller of the present invention is connected to different switches.
Embodiment
As shown in Figure 1, method of the present invention comprises the following steps:
1) realize that by a dedicated network data are synchronous between the redundancy process control station;
2) engineer station or SCADA system are connected to switch by a network (physical form can be two kinds of electricity, light), and each process control station is connected with switch simultaneously;
3) the logical described network of the process control station in " activation " state sends first via heartbeat signal (a frame traffic message) to the process control station in " standby " state, sends the fixed cycle that the first via heartbeat signal cycle is defaulted as setting;
4) set up a system variable in each process control station;
5) revise described system variable data in steering logic of the every execution of the process control station of " activation " state, every variable data of taking turns adds 1;
6) process control station in " activation " state while sending to the process control station in " standby " state, comprises the second road heartbeat signal by every synchrodata of taking turns by network, and the data that are about to described system variable are also synchronously pass by;
7) the process control station receiving isochronous data in " standby " state also compares data and last receive whether identical of system variable in synchrodata, if it is not identical, show in the process control station of " activation " state working properlyly, be left intact;
8), if twice numerical value is identical, check whether the process control station first via heartbeat signal in " activation " state exists
;
9), if first via heartbeat signal disappears, the process control station in " standby " state is self " activation ", thereby obtains the control to field apparatus
,if first via heartbeat signal does not disappear, two-way heartbeat signal Jin You mono-tunnel fault is described, the while also shows in the process control station of " activation " state working properly, is left intact
.
Two in the redundancy process control station independently have a dedicated network to realize that data are synchronous between process control station.
Two process control stations, engineer station's (SCADA system; both can share a computer usually; also can be configured to respectively different computers) all there is a network to be connected on same switch; also can be connected respectively to different switches; if while being connected to different switch, these switches need cascade.
Process control station in " activation " state sends " heartbeat " signal to the process control station in " standby " state by the network through switch;
Process control in " activation " state stands in while by dedicated network, realizing that data are synchronized to the process control station in " standby " state, has comprised a simulation " heartbeat " variable in synchrodata;
Process control station in " standby " state must could be carried out " activation " self operation when both breaking down, thereby grabs control.
Advantage of the present invention is as follows:
1) do not need to increase any hardware cost;
2) effectively avoid two process control stations causing because of the redundant dedicated network failure all in " activation " state, grab the control to field apparatus, thus the unpredictable consequence that process control is caused.
3) effectively utilize the software function that must realize in process controller and it reasonably revised, the real-time that the reliability that both can guarantee redundancy switching also can the keep-process control station, and on software is realized also very simple.
technical term:
The engineer station: for industrial process control engineering teacher, can carry out the generation of database, the generation of production procedure picture, the workstation of the configuration in stepless control loop etc.
Process control station: refer to that top-grade computer is that form, Intelligent Information Processing unit built-in operating system for interior the having of a control system.Process control station is the CPU (central processing unit) of scattered control system (DCS), is the core component of DCS, is responsible for the computing of steering logic and the processing of input signal and output order, also needs the communication function between realization and SCADA simultaneously.
IO communication process module: refer to the intermediate information crosspoint that some controllers data acquisition fastener associated with it connects by network.
Below only with most preferred embodiment, the present invention is described further, and so it is not limitation of the invention, and protection scope of the present invention is as the criterion with the content that is illustrated in claim.
Claims (3)
1. redundancy switching method between the redundancy process control station in a scattered control system, is characterized in that, comprises the following steps:
1) realize that by a dedicated network data are synchronous between the redundancy process control station;
2) engineer station or SCADA system are connected to switch by a network, and each process control station is connected with switch simultaneously;
3) the logical described network of the process control station in " activation " state sends first via heartbeat signal to the process control station in " standby " state, sends the fixed cycle that the first via heartbeat signal cycle is defaulted as setting;
4) set up a system variable in each process control station;
5) revise described system variable data in steering logic of the every execution of the process control station of " activation " state, every variable data of taking turns adds 1;
6) process control station in " activation " state while sending to the process control station in " standby " state, comprises the second road heartbeat signal by every synchrodata of taking turns by network, and the data that are about to described system variable are also synchronously pass by;
7) the process control station receiving isochronous data in " standby " state also compares data and last receive whether identical of system variable in synchrodata, if it is not identical, show in the process control station of " activation " state working properlyly, be left intact;
8), if twice numerical value is identical, check whether the process control station first via heartbeat signal in " activation " state exists;
9), if first via heartbeat signal disappears, the process control station in " standby " state is self " activation ", thereby obtains the control to field apparatus
,if first via heartbeat signal does not disappear, two-way heartbeat signal Jin You mono-tunnel fault is described, the while also shows in the process control station of " activation " state working properly, is left intact.
2. redundancy switching method between the redundancy process control station in scattered control system according to claim 1, it is characterized in that: in described step 2) in, described switch is one or more, direct-connected between each switch while being a plurality of when switch, each switch is connected with a process control station.
3. redundancy switching method between the redundancy process control station in scattered control system according to claim 1, it is characterized in that: in described step 3), the fixed cycle is 200 milliseconds.
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Cited By (10)
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| CN104320311A (en) * | 2014-11-20 | 2015-01-28 | 国电南京自动化股份有限公司 | Heartbeat detection method of SCADA distribution type platform |
| CN104571040A (en) * | 2014-12-31 | 2015-04-29 | 重庆川仪自动化股份有限公司 | Construction method of control system redundancy framework |
| CN105404287A (en) * | 2015-12-27 | 2016-03-16 | 彭晔 | Heartbeat protocol-based control switching method of supervisory control and data acquisition system |
| CN107992027A (en) * | 2017-12-13 | 2018-05-04 | 中核控制系统工程有限公司 | A kind of DCS redundant communication modules switching method |
| CN109274553A (en) * | 2018-09-26 | 2019-01-25 | 北京广利核系统工程有限公司 | The self-diagnosing method and device of nuclear safe level DCS system communication |
| CN109491238A (en) * | 2018-12-12 | 2019-03-19 | 南京工程学院 | Subway platform accelerator control system controller redundancy approach |
| CN109739202A (en) * | 2019-02-19 | 2019-05-10 | 西门子工厂自动化工程有限公司 | Production management system |
| CN109981353A (en) * | 2019-03-06 | 2019-07-05 | 北京全路通信信号研究设计院集团有限公司 | Neighboring station redundancy protected method and system in a kind of machine frame formula network communication equipment |
| CN113660150A (en) * | 2021-06-25 | 2021-11-16 | 南京国电南自维美德自动化有限公司 | Process control station access system and access method |
| CN113985823A (en) * | 2021-09-16 | 2022-01-28 | 南京国电南自维美德自动化有限公司 | Online monitoring method and system for network communication between process control stations of distributed control system |
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| CN104320311A (en) * | 2014-11-20 | 2015-01-28 | 国电南京自动化股份有限公司 | Heartbeat detection method of SCADA distribution type platform |
| CN104571040A (en) * | 2014-12-31 | 2015-04-29 | 重庆川仪自动化股份有限公司 | Construction method of control system redundancy framework |
| CN105404287A (en) * | 2015-12-27 | 2016-03-16 | 彭晔 | Heartbeat protocol-based control switching method of supervisory control and data acquisition system |
| CN105404287B (en) * | 2015-12-27 | 2018-02-06 | 彭晔 | The control switching method of data acquisition analysis system based on heart-beat protocol |
| CN107992027A (en) * | 2017-12-13 | 2018-05-04 | 中核控制系统工程有限公司 | A kind of DCS redundant communication modules switching method |
| CN107992027B (en) * | 2017-12-13 | 2020-05-22 | 中核控制系统工程有限公司 | DCS redundant communication module switching method |
| CN109274553A (en) * | 2018-09-26 | 2019-01-25 | 北京广利核系统工程有限公司 | The self-diagnosing method and device of nuclear safe level DCS system communication |
| CN109491238A (en) * | 2018-12-12 | 2019-03-19 | 南京工程学院 | Subway platform accelerator control system controller redundancy approach |
| CN109739202B (en) * | 2019-02-19 | 2020-10-16 | 西门子工厂自动化工程有限公司 | Production management system |
| CN109739202A (en) * | 2019-02-19 | 2019-05-10 | 西门子工厂自动化工程有限公司 | Production management system |
| CN109981353A (en) * | 2019-03-06 | 2019-07-05 | 北京全路通信信号研究设计院集团有限公司 | Neighboring station redundancy protected method and system in a kind of machine frame formula network communication equipment |
| CN109981353B (en) * | 2019-03-06 | 2022-05-24 | 北京全路通信信号研究设计院集团有限公司 | Method and system for protecting adjacent station redundancy in frame type network communication equipment |
| CN113660150A (en) * | 2021-06-25 | 2021-11-16 | 南京国电南自维美德自动化有限公司 | Process control station access system and access method |
| CN113660150B (en) * | 2021-06-25 | 2023-01-03 | 南京国电南自维美德自动化有限公司 | Process control station access system and access method |
| CN113985823A (en) * | 2021-09-16 | 2022-01-28 | 南京国电南自维美德自动化有限公司 | Online monitoring method and system for network communication between process control stations of distributed control system |
| CN113985823B (en) * | 2021-09-16 | 2023-12-26 | 南京国电南自维美德自动化有限公司 | Online monitoring method and system for network communication between process control stations of distributed control system |
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Address after: 210032 Jiangsu province Nanjing city Pukou high tech Zone Huidalu No. 9 Patentee after: Nanjing Guodian Nanzi 710086 Automation Co. Ltd. Address before: Nanjing City, Jiangsu province 210032 Spark Road, Pukou hi tech Development Zone No. 8 Patentee before: Nanjing Guodian Nanzi Meizhuo Control System Co.,Ltd. |