JP5377448B2 - Control device programming tool and control device program creation support method - Google Patents

Description

  The present invention relates to a programming tool for a control device and a method for supporting creation of a program for a control device, and more particularly, to a network that conforms to a functional safety standard (IEC 61508) established by the IEC (International Electrotechnical Commission). The present invention relates to a programming tool for a control device that supports creation of a program for a process control device that controls a plant system by communicating between a plurality of controllers using a connected transfer memory, and a creation support method for a control device program.

  In general, process control in various plant systems is performed by connecting a plurality of controllers via a network and sharing the data among the controllers. As described above, for example, a technique described in Patent Document 1 is known as a conventional technique that enables data to be shared among a plurality of controllers.

  This prior art relates to a cyclic transfer communication technique using a transfer memory, in which a transfer memory and a local processor are provided in each of a plurality of controllers, and communication between the controllers is controlled by the local processor. Each local processor periodically broadcasts data assigned to its own controller on the transfer memory to other computers, thereby matching the data in the transfer memory in each controller.

  On the other hand, functional safety is required for communication between controllers in order to reduce the risk of plant systems. Functional safety is the idea that functions are implemented so that the safety of systems and equipment can be ensured even if a failure occurs. Functional safety communication is performed between one-to-one equipment. It is common to use packet communication called request-response.

  And the technology of handshake communication that performs communication while confirming data transmission / reception as communication between multiple controllers using transfer memory, which makes the concept of functional safety and control of the plant system as described above compatible. It is also possible to use.

Japanese Patent Laid-Open No. 7-219902

  In the execution of application programs in process control in various plant systems, if the data transfer processing of variables to be put on the communication between controllers is asynchronous with the communication processing, the variable data may not be transmitted accurately to the receiving side as expected. .

  A programming tool for a control device that supports the creation of a program for a process control device according to the prior art must find data variables that become asynchronous by an application program execution test, which increases test costs and increases test efficiency. It has the problem of inviting a decline.

  In addition, communication can be performed so that all data to be put on communication can be synchronized, but in order to synchronize, communication is performed while confirming transmission / reception of all transmission data between a plurality of controllers. A communication protocol (transmission request / reception response) to be performed is required, which causes a problem of increasing the communication load of the controller that performs process control of the plant system.

  In addition, some of the transmission data communicated between controllers cannot be used for continuous plant operation unless synchronization is established. Although it is possible to extract and program automatically synchronously, it is unrealistic as an implementation method.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the above-described conventional programming tool for a control device, and to control the process by transmitting and receiving data between a plurality of controllers and sharing the data. Control device programming tool and control device program creation support method capable of finding a transmission data variable in which transmission / reception of data between a plurality of controllers is asynchronous in a programming stage Is to provide.

  According to the present invention, the object is to provide a programming tool for a control device that supports creation of a program for a process control device that performs data control among a plurality of controllers and shares the data to control the process. The process control device for which the creation support is received receives a transfer memory that holds data to be transmitted / received to / from another controller via the network and data periodically transmitted from the other controller. A communication processor that sequentially updates data on the reception area of the transfer memory, periodically transmits transmission data on the transmission area of the transfer memory to other controllers, and transmission data to be transmitted to other controllers. A controller having a CPU for writing to the transmission area of the transfer memory via a network A plurality of controllers connected to each other to perform process control, the control device programming tool comprising: an editor for editing a program for each of the plurality of controllers to control a process; When the controller downloads and executes the execution module, the compiler that converts the program into an execution module that can be executed by each controller, and when the controller downloads and executes the data, a process of transmitting and receiving data between the controllers occurs. Means to detect that data is not being transmitted correctly due to the asynchronousness caused by the difference between the data write cycle and the data read cycle from the transfer memory on the receiving side, and when data is not transmitted correctly Achieved by providing means for warning

  According to the present invention, it is possible to extract transmission data (variables) to be synchronized in a programming stage and to issue an alarm when expected data (variables) are not transmitted accurately.

It is a block diagram which shows the structure of the programming tool for control apparatuses by one Embodiment of this invention, and a simulation process control apparatus. It is a figure which shows the process of data transfer between controllers, and a data flow. It is a figure explaining the structure of CPU which processes the application program for performing communication between controllers, and the fundamental operation | movement of communication. It is a time chart when the transmission side and the reception side are correctly synchronized. FIG. 10 is a time chart when the transmission side and the reception side are not correctly synchronized and the reception data read cycle is longer than the transmission data write cycle. FIG. It is a time chart when the transmission side and the reception side are not correctly synchronized and the transmission data write cycle is longer than the reception data read cycle. It is a figure which shows the structural example of the screen which alerts an operator with a programming tool.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a control device programming tool and a control device program creation support method according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a block diagram showing the configuration of a controller programming tool and a simulated process controller according to an embodiment of the present invention.

  The simulated process control apparatus shown in FIG. 1 simulates a process that is a target when the programming tool for the control apparatus according to the embodiment of the present invention supports the creation of a program. It may be formed by software. The pseudo process control apparatus includes a plurality of controllers 101 and 201 that perform calculation / control on the control target, sensors 107 and 207 that detect the operation state of the control target, and detection signals from the sensors 107 and 207. The signal input devices 106 and 206 that receive and transfer to the controllers 101 and 201, and the signal output devices 108 and 208 that transfer control signals from the controllers 101 and 201 to the actuators 109 and 209, respectively. A control device programming tool 301 according to an embodiment of the present invention is constructed in a personal computer or the like, and includes an editor 303 and a compiler 304.

  In the above description, the controllers 101 and 201 are connected by a network 901 that connects a plurality of controllers, and transfer data is exchanged between the controllers 101 and 201. The transmission / reception of the transmission data is performed under the control of the execution module received from the controller execution tool 301 connected from the control device programming tool 301 connected via the network 901.

The controllers 101 and 201 that control the control target perform communication processing between the central processing units (CPUs) 102 and 202 that perform information processing of the controller including application program execution processing, and the CPUs 102 and 202. Communication processors (NCP) 103 and 203 having transfer memories 104 and 204 that are directly read / written from
The system buses 105 and 205 connect the CPUs 102 and 202 and the NCPs 103 and 203 to each other. Since the transfer memories 104 and 204 are used for transmitting and receiving data between the controllers 101 and 102, the transfer memories 104 and 204 include a transmission area for storing transmission data and a reception area for storing reception data. ing. In the following description, the transmission area and the reception area are simply referred to as a transfer memory without being distinguished from each other.

  As described above, since the process control apparatus configured to include the controllers 101 and 201 is controlled, the control apparatus programming tool according to the embodiment of the present invention supports the creation of a program for the process control apparatus. This is a pseudo-product used in the process, and does not actually control the process.

  An editor 303 provided in the programming tool 301 edits the controller 101 program 302A and the controller 102 program 302B, which are programs to be executed by the controllers 101 and 201.

  The above-mentioned programs 302A and 302B are programmed using a PLC (Programmable Logic Controller) programming language of IEC61131-3 standard, which is a so-called international standard, but since this programming language is generally known, The description here is omitted.

  A compiler 304 provided in the programming tool 301 compiles the programs 302A and 302B, and is an execution module that has a format in which the programs 302A and 302B edited by the editor 303 can be executed on the controllers 101 and 201. The execution module 305A for the controller 101 and the execution module 305B for the controller 102 are converted. Execution modules 305A and 305B converted into an executable format are downloaded to the respective controllers 101 and 201 constituting the process control apparatus via the network 901 and execute process control processing.

  In the above description, an example in which two controllers 101 and 201 are connected to the network 901 has been described. However, the number of controllers connected to the network 901 is not limited to this, and a larger number of controllers are connected. A controller may be connected to the network 901.

  For example, a general power plant is provided with a plurality of controllers, a plurality of valves, valves, etc. corresponding to a certain load side device for the purpose of improving the operating rate and reliability of the whole plant. In many cases, multiple control is used in which multiplexed process data signals are shared among a plurality of controllers and collation / selection processing or the like is performed in each controller. In order to perform such multiple control, data exchange between controllers is indispensable.

  FIG. 2 is a diagram showing a data transfer process and data flow between controllers. In the example shown in FIG. 2, a detection signal from a sensor on the controller 101 side is received by the CPU 102 in the controller 101 and processed, and the processed data is output to the transfer memory 104, and the network 901 is transferred from the transfer memory 104. The data is transferred to the transfer memory 204 in the controller 201 via the CPU 201, and the CPU 202 of the controller 201 receives the data in the transfer memory 204 for processing, and outputs the processed data to the valve to control the valve. It is.

  In the example shown in FIG. 2, when data is transmitted from the transfer memory 104 that holds transmission data, the cycle and phase for sampling the data, and the transfer memory 204 that receives the received data and holds the received data. If the period and phase at which data is read out for processing are not correctly synchronized, there will be an asynchronous problem that the data may not be transmitted accurately as expected.

  FIG. 3 is a diagram illustrating the configuration of the CPUs 102 and 202 that process an application program for performing communication between controllers and the basic operation of communication. The communication described here has the same contents as described with reference to FIG.

  As shown in FIG. 3, the CPU 102 in the controller 101 takes in the counter program 401 and the collation program 404 as application programs and processes these programs. Similarly, the CPU 202 in the controller 201 The counter program 501 and the collation program 504 are taken in and these programs are processed.

  Here, the communication operation will be described as an example in which data is transmitted from the CPU 102 of the controller 101 to the CPU 202 of the controller 201. However, even when data is transmitted from the CPU 202 of the controller 201 to the CPU 102 of the controller 101, data transmission is performed. The basic operation content is the same as the example in which data is transmitted from the CPU 102, and therefore the description thereof is omitted.

  The transmission program is generated by the CPU 102 by the counter program 401 in the controller 101. Then, the generated transmission program writes transmission data 402 that is periodically updated in the transfer memory 104. The transmission data 402 is written into the transfer memory 104 by sampling the transmission data 402 at a constant cycle by the transmission program.

  Transmission data in the transfer memory 104 is periodically transmitted to the controller 201 side via the network 901 at a period different from the period at which the transmission program samples the transmission data 402. At that time, a transmission source and a reception source are set in the transmission data.

  The transfer memory 204 of the controller 201 on the reception side receives the data transmitted from the transfer memory 104 of the transmission side controller 101 and stores it in the self-transfer memory 204. A reception program (not shown) generated by the CPU 202 by the counter program 504 in the controller 201 periodically reads the reception data 502 from the transfer memory 204 at a period different from the period in which the data is transmitted, and reads it into the verification program 501. Pass data.

  The collation program 501 collates the current value, which is the value of the data received this time, with the previous value, which is the value of the data received last time, and whether or not the data to be transmitted is reliably received based on the result of the collation. Judging. This determination is performed by determining that the data to be transmitted is not correctly received when the collation program 501 performs the collation over a plurality of times and continues to be consistent for a certain number of times. . In other words, the collation program 501 determines that the data to be transmitted is correctly received when the collation results are repeatedly mismatched every certain number of times as a result of collation over a plurality of times.

  As described above, the transmission program generated by the CPU 102 samples the transmission data 402 and writes it in the transfer memory 104, and the reception program generated by the CPU 202 reads the reception data 502 from the transfer memory 204 and passes it to the verification program 501. If the period is synchronized, the transmitted data is surely passed to the receiving side.

  However, if the synchronization as described above is not achieved, the transmitted data may not pass to the receiving side. In order to find such asynchronous transmission data, the programming tool needs to test many times by adjusting the timing.

  Hereinafter, the synchronization between the transmission side and the reception side will be described with reference to time charts showing synchronous and asynchronous situations.

  FIG. 4 is a time chart when the transmitting side and the receiving side are correctly synchronized, and FIG. 5 is a case where the transmitting side and the receiving side are not correctly synchronized, and the read data read cycle is greater than the transmit data write cycle. FIG. 6 is a time chart when the transmission side and the reception side are not correctly synchronized, and when the transmission data write cycle is longer than the reception data read cycle.

  Whether the sending side and the receiving side are correctly synchronized depends on whether the timing (cycle) at which data is written to the transfer memory on the sending side matches the timing (cycle) at which the received data is read from the transfer memory on the receiving side. It depends on whether or not.

  In the example shown in FIG. 4, the cycle for writing the transmission data to the transfer memory on the transmission side coincides with the cycle for reading the reception data from the transfer memory on the reception side. Therefore, in the example shown in FIG. 4, data transmitted from the transmission side is correctly received at the reception side.

  In the example shown in FIG. 5, the period at which reception data is read from the reception-side transfer memory on the reception side is longer than the period at which transmission data is written to the transmission-side transfer memory, and the 1-bit period of the read data (data change As a result, the data to be read is always a specific value, “1” in the illustrated example, which is meaningless. In the example shown in FIG. 6, the cycle for writing the transmission data to the transfer memory on the transmission side is longer than the cycle for reading the reception data from the transfer memory on the reception side, and the 1-bit cycle of the transmission data (data change) As a result, the transmission data stored in the transmission memory on the transmission side is always a specific value, “1” in the illustrated example, which is meaningless.

  In order to check the synchronization state as described above, it is necessary to extract the program that writes data to the transfer memory on the transmission side and the program that reads data from the transfer memory on the reception side, and whether or not there is a difference in operation timing. It is effective to judge.

  In the embodiment of the present invention, when the programming tool 301 compiles the program, the compiler 304 extracts the transmission data 402 of the counter program 401 and the reception data 502 of the collation program 501 and collates them, so that there is a difference in timing. If there is a difference in timing, the fact is displayed on the display screen of the programming tool 301 to warn the operator.

  In addition, the programming tool 301 according to the embodiment of the present invention tests the transmission side and the reception side by testing whether or not the behavior of the reception data 502 of the collation program 501 matches the transmission data 402 of the counter program 401. The synchronization state can be confirmed.

  Further, the programming tool 301 according to the embodiment of the present invention can load and execute the counter program 401 on the CPU 202 in order to check the expected data behavior in the program execution stage in the actual process control apparatus. Thereby, the behavior of the expected data and the received data 502 can be compared, and if the behavior is different, a warning can be issued to the operator.

  In addition, since the transfer cycle of data to the transfer memory is slower than the transmission data change interval, the transmission data cannot be transmitted correctly. This is because the cycle of writing data to the transfer memory is long, or the data is read from the transfer memory. By thinking in the same way as the asynchronous problem due to the long period, it can be solved as described above.

  FIG. 7 is a diagram showing a configuration example of a screen for warning a worker with a programming tool.

  The screen on which the programming tool 301 gives a warning to the operator is a program selection screen area 603 that shows the program configuration of the controller 101 and the controller 201 and allows selection of those programs, and a program that displays the program selected in the program selection screen area 603. A display editing screen area 601 and a warning message screen area 602 for displaying a warning message for processing in the program displayed in the program display editing screen area 601 are configured.

  FIG. 7 shows an example in which a collation program is selected as a program in the controller 201 and displayed in the program display edit screen area 601. In the program display edit screen area 601, the current value of the received data is input to the FB1 for collation processing as the input X, and the previous value in its own controller is input to the FB1 for collation processing as the input Y. As a result of the collation, the output Z is displayed. In the warning message screen area 602, “X input is not synchronized” is displayed as an example of the warning message.

101, 201 Controller 102, 202 Central processing unit (CPU)
103, 203 Communication processor (NCP)
104, 204 Transfer memory 105, 205 System bus 106, 206 Signal input device 107, 207 Sensor 108, 208 Signal output device 109, 209 Actuator 301 Programming tool 302A 102 program 302B 202 program 303 Editor 304 Compiler 305A 102 execution module 305B 202 execution module 401, 504 Counter program 404, 501 Verification program 901 Network

Claims (5)

In a programming tool for a control device that supports creation of a program for a process control device that performs process control by transmitting and receiving data between a plurality of controllers and sharing data,
The process control device that supports program creation receives a transfer memory that holds data to be transmitted to and received from other controllers via the network, and data that is periodically transmitted from other controllers. A communication processor that sequentially updates the data on the receiving area of the transfer memory and periodically transmits the transmission data on the transmission area of the transfer memory to the other controllers, and the transmission data to be transmitted to the other controllers. A process control device configured to connect a plurality of controllers including a CPU for writing to the transmission area of the transfer memory via a network to perform process control,
The controller programming tool includes: an editor that edits a program for each of the plurality of controllers to control a process; a compiler that converts the edited program into an execution module executable by each controller; and the controller When the execution module is downloaded and executed, a process of transmitting / receiving data between controllers occurs, and the difference between the cycle of writing data to the transfer memory on the transmission side and the cycle of reading data from the transfer memory on the reception side A control device programming tool, comprising: means for detecting that data is not correctly transmitted due to asynchrony caused by the above; and means for warning that data has not been transmitted correctly.   The means for detecting that the data is not correctly transmitted due to the asynchronization caused by the difference between the cycle of writing data in the transfer memory on the transmission side and the cycle of reading data from the transfer memory on the reception side is the transmission data is transmitted at a constant cycle. It is sampled and written in the transmission area of the transfer memory on the transmission side, transmitted at a cycle different from the sampling cycle, received and stored in the reception area of the transfer memory on the reception side, and the received data is transmitted. 2. The control device programming tool according to claim 1, further comprising collating means for periodically reading out a period different from the period and collating the current received data with the previous received data.   2. The control device programming tool according to claim 1, wherein the process control device to which the program creation support is performed is formed in software in the control device programming tool.   The process control device for which the program creation support is performed is an actual process control device, and the programming tool for the control device checks the expected data behavior in the program execution stage in the actual process control device. The controller programming tool according to claim 1, further comprising means. In a method for supporting creation of a program for a control device in a programming tool for a control device that supports creation of a program for a process control device that performs process control by transmitting and receiving data between a plurality of controllers and sharing data,
The process control device that supports program creation receives a transfer memory that holds data to be transmitted to and received from other controllers via the network, and data that is periodically transmitted from other controllers. A communication processor that sequentially updates the data on the receiving area of the transfer memory and periodically transmits the transmission data on the transmission area of the transfer memory to the other controllers, and the transmission data to be transmitted to the other controllers. A process control device configured to connect a plurality of controllers including a CPU for writing to the transmission area of the transfer memory via a network to perform process control,
The control device programming tool edits a program for each of the plurality of controllers to control a process, converts the edited program into an execution module executable by each controller, and the controller executes the execution module. When data is downloaded and executed, processing to send and receive data between controllers occurs. A method for supporting the creation of a program for a control device, characterized by detecting that data is not correctly transmitted and warning that the data is not correctly transmitted.

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