JP5717709B2 - Instrumentation system - Google Patents

Description

  The present invention relates to an instrumentation system, and more particularly to an instrumentation system to which a centralized control method using an FT (Fault Tolerance) server is applied.

  2. Description of the Related Art Conventionally, a distributed control system (DCS: Distributed Control System) that performs supervisory control by distributing a plurality of controllers in a plant is known as a supervisory control system in large-scale plants such as iron making, papermaking, essential oil, and shipping power. (For example, refer to Patent Document 1). The DCS includes individual devices in a plant, sensors installed in a machine, a plurality of controllers connected to actuators, and a console as a man-machine interface. The console and the plurality of controllers are connected via a dedicated network. The controller includes a communication interface (IF) with a dedicated network, input / output interfaces (I / O) with sensors and actuators, and a processing unit (CPU), and consoles sensor information from individual devices and machines. And control individual devices and machines based on commands from the console.

  A monitoring control system using a PLC (Programmable Logic Controller) as a controller has also been known (see, for example, Patent Document 2). PLC implement | achieves the sequence circuit comprised by the relay and the timer by running the special program based on ladder logic on a processor.

  In recent years, with the advancement of computer and communication network functions, server computers and client computers connected to dedicated networks have been used to analyze information collected from plants, and to enhance monitoring and control. Or monitoring control from a remote location (see, for example, Patent Document 3).

JP 2002-049405 A JP 2010-146256 A JP 2010-2111377 A

  FIG. 1 shows the configuration of a conventional distributed control system. In the distributed control system (DCS) 1, a plurality of computers (PC) 2 a and 2 b functioning as a console, a plurality of controllers 3 a, 3 b,... 3 n and a gateway (GW) 4 are connected via a controller network 5. Has been. The controller 3 is connected to individual devices in the plant, sensors 6 provided in the machine, servo motors 7, actuators 8 such as control valves, and the like. The controller 3 includes an input / output interface (I / O) 31 with a sensor 6, an actuator 8, and the like, and a processing device (CPU) 32. The GW 4 is an interface with an external network 9 such as a LAN or a WAN.

  The I / O 31 can be increased / decreased for each controller 3 depending on the device and machine to be monitored and controlled, and the controller 3 can also be increased / decreased on the controller network 5 according to the scale of the equipment. It has become. The I / O 31 performs signal format conversion (A / D conversion, D / A conversion) of the monitoring signal and the control signal between the sensor 6, the actuator 8, and the like and the CPU 32. The CPU 32 collects monitoring signals from the sensors 6 of the individual devices and machines and transfers them to the PC 2. Further, the CPU 32 executes a control program stored in advance based on a command from the PC 2 and a monitoring signal, generates a control signal for controlling individual devices and machines, and supplies the control signal to the actuator 8 or the like. Send.

  Since the controller 3 is an expensive computer system, it is arranged in a dedicated space such as an instrument room in the plant, and is arranged in an instrument room equipped with air conditioning equipment according to the environment in the plant. The controller 3 is duplicated together with the controller network 5 from the viewpoint of reliability. Thus, a large number of expensive controllers must be installed in the plant, and the installation of the DCS 1 has a problem of enormous costs.

  In addition, since a large number of controllers 3 are distributed in the plant, maintenance such as program updating is necessary for the large number of CPUs 32, and there is a cost in terms of maintenance operations. Every time the number of CPUs 32 increases. Reliability will be reduced. In addition, since a large number of controllers 3 are distributed, there is a problem that a large installation location is required.

  Since signal transmission for supervisory control with respect to the controller 3 requires immediacy, the PC 2 and the plurality of controllers 3 are connected by a dedicated network. On the other hand, signal transmission for a common operation between the PC 2 and another computer does not need immediacy, but does not match the dedicated network as described above because it transfers a large amount of information. In addition, connection with other computers and networks requires the use of a dedicated GW 4, which has a problem of lack of expandability.

  On the other hand, the PLC is a controller mainly specialized for an ON / OFF monitoring control system, and duplexing is delayed as compared with DCS, which is slightly inferior in terms of reliability. However, there is an advantage that the initial cost is less than the controller 3 of the DCS 1 described above. On the other hand, in the control by the PLC, there is a problem that programming specialized for the PLC is required and the versatility is lacking. Further, since the PLC processor generally has a small processing capacity, when a monitoring control system for a large-scale plant is constructed, more PLCs must be installed than the number of DCS controllers.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an instrumentation system having high expandability and versatility because both initial cost and maintenance operation cost are low. It is in.

In order to achieve such an object, according to one embodiment, in an instrumentation system that performs supervisory control of a plant, a computer that is connected to a communication network and executes the supervisory control program of the plant, and a device in the plant A translator connected to a monitoring element and a control element, transferring a monitoring signal from the monitoring element to a relay network, and transferring a control signal from the relay network to the control element; and from the translator via the relay network A third CPU that receives the monitoring signal; a second CPU that executes a monitoring program to generate monitoring information from the monitoring signal; and a first CPU that transmits the monitoring information to the computer via the communication network. The first CPU is configured to communicate with the communication network. Control information is received from the computer via a network, the second CPU executes a control program to generate the control signal from the control information, and the third CPU relays the control signal to the relay The third CPU operates in a predetermined monitoring control cycle, the second CPU operates in a control calculation cycle different from the monitoring control cycle, and transmits to the translator via the network . The CPU includes a server that operates asynchronously with the monitoring control cycle and the control calculation cycle .

Also, the server may be a duplicated FT (Fault Tolerance) server.

  Further, a PLC inserted between the server and the relay network, and further detects a PLC that shuts off communication between the server and the translator when a failure of the server or the equipment in the plant is detected. It can also be provided.

  As described above, according to the present invention, since the CPU mounted on the conventional controller is concentrated on the server, the initial cost for installing the instrumentation system can be greatly reduced. Since the translator is specialized in function only for signal relay, the cost of the apparatus can be greatly reduced. In addition to the relay network that is specialized for signal relay and ensures immediacy, a general-purpose communication network is used to connect the server and the computer. In addition, an instrument system with high expandability and versatility can be provided.

It is a figure which shows the structure of the conventional distributed control system. It is a figure which shows the instrumentation system concerning one Embodiment of this invention. It is a figure which shows the structure of the FT server concerning one Embodiment of this invention. It is a figure which shows the structure of the database of an FT server. It is a figure which shows the sequence of the process by FT server.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 2 shows an instrumentation system according to an embodiment of the present invention. In the instrumentation system 100, a plurality of computers (PCs) 102a and 102b functioning as consoles and an FT (Fault Tolerance) server 101 are connected via a redundant LAN 104. The LAN 104 is connected to an external network 109 such as a WAN. On the other hand, the FT server 101 and a plurality of translators 103a, 103b,... 103n are connected via a translator network 105 specialized for signal relay. An engineering workstation (WS) 110 is connected to the FT server 101 for maintenance work such as programming.

  The PC 102 is an HMI (Human Machine Interface) for monitoring and operating individual devices and machines in the plant, and is a computer that executes a plant monitoring operation program. In FIG. 2, although shown as one computer, it can be duplicated by a normal (N) system and a standby (E) system, or a redundant configuration with a plurality of computers can be adopted. In addition, a plurality of computers can be provided for each function such as monitoring operation, data analysis, and production management.

  The translator 103 is an input / output interface (I / O) connected to an individual device in the plant, a sensor 106 as a monitoring element provided in the machine, a servo motor 107 as a control element, an actuator 108 such as a control valve, and the like. O) A plurality of 131 are provided. In addition, a common control unit (COM) for connecting a plurality of I / O 131 and the translator network 105 is provided. The I / O 131 can be increased or decreased for each translator depending on the device or machine that is the object of the monitoring operation, and the translator 103 can also be increased or decreased on the translator network 105 according to the scale of the facility. ing.

  With such a configuration, the CPU mounted on the conventional controller is concentrated on the FT server, so that the instrumentation system 100 is configured with a centralized control system (C / C (registered trademark): Concentrated Control System (registered trademark). Trademark)). The FT server 101 is an expensive computer system and is arranged in a dedicated space such as an instrument room in the plant. However, since only one unit is required in the plant, the initial cost for installing the instrumentation system 100 is low. The installation space can be greatly reduced compared with DCS.

  The translator 103 has only a function as a relay for transferring a monitoring signal from the sensor 106 or the like to the FT server 101 or transferring a control signal from the FT server 101 to the actuator 107. Since the function is specialized only for signal relay, it is relatively easy to configure the translator 103 that can operate even in an environment without air conditioning equipment. Therefore, even if a large number of translators 103 are installed in the plant and are duplicated from the viewpoint of reliability, not only the device cost but also the installation space and the constraints for installation are greatly reduced as compared with the conventional controller. be able to.

  In addition, since the CPUs distributed in the conventional DCS are consolidated and the air conditioner for installing the conventional controller becomes unnecessary, each maintenance work is reduced. On the other hand, since many translators installed in the plant have specialized functions, maintenance work can be greatly reduced.

  Further, the LAN 104 is a communication network composed of Ethernet (registered trademark) (1 GBPS) and TCP / IP protocol stacks, and is duplicated. Since the LAN 104 is a general-purpose communication network, the PC 2 and the FT server 101 can be easily connected to other computers and the external network 109, and monitoring control from other remote control systems becomes possible. High scalability.

  FIG. 3 shows a configuration of an FT server according to an embodiment of the present invention. The FT server 101 includes a normal (N) system and a standby (E) system in a hot standby state, and is a fully duplexed server (hereinafter, reference numerals N and E are omitted). The processing devices (CPU) 201-203 are configured in three layers according to the function to be processed. The databases (DB1-DB3) 211-213 are also configured in three layers corresponding to the CPUs in each layer and are duplicated. The CPU 201-203 and the database 211-213 are connected by a duplex bus 204 of 100 Gb / s by optical fiber transmission. Further, the power source (POW) 205 is also duplicated, and a plurality of batteries (BATT) 206 are also provided.

  The CPU 201 is connected to the LAN 104 and performs communication processing such as exchange of monitoring information and operation information with the PC 102. The CPU 202 executes a monitoring program for generating monitoring information by performing alarm processing of the monitoring signal from the translator 103 and a control program for generating a control signal based on operation information from the PC 102. The CPU 203 is connected to the translator network 105 and performs communication processing with the translator 103. The contents of each process in the CPU 201-203 will be described later.

  In the conventional DCS, since controllers are arranged corresponding to individual devices and machines in the plant, the CPU of the controller executes a monitoring control program corresponding to each device and machine. In other words, monitoring signals are collected, signal format conversion, alarm processing, etc. are performed, and upload processing is transferred to a PC, and a control program stored in advance is executed based on commands from the PC and monitoring signals. The download processing for transmitting a control signal for controlling the individual devices and machines is executed for each individual device and machine.

  On the other hand, the FT server 101 of the present embodiment is connected to all devices and machines in the plant, and is connected to 1) an interface with a PC, 2) supervisory control, and 3) I / O by a three-level CPU. Functions are distributed to the interface.

  In the present embodiment, the CPU 203 and the translator network 105 are connected via the controller (PLC) 207. The PLC 207 detects failures in individual devices, machines, translators 103, and FT servers 101 in the plant, and detects abnormalities in the operation of the devices and machines in the plant. When the PLC 207 detects a failure of the FT server 101 or a device or machine in the plant, the PLC 207 autonomously shuts down the connection between the CPU 203 and the translator network 105, and an abnormal monitoring signal is transferred from the translator 103 to the CPU 203. Is preventing. In addition, when an abnormality in the operation of an apparatus or a machine in the plant is detected, transmission of a control signal to the apparatus or machine in which the abnormality is detected is interrupted. In this way, unnecessary control signals are prevented from being transferred from the CPU 203 to the translator 103.

  This function is based on the concept of a safety instrumented (SIS) system, so that a failure that occurs in one element of the system does not spread to other elements. According to the control of the PLC 207, the time from the detection of the failure to the shutdown is overwhelmingly faster than the control of the CPU 202, and the on-site actuator 108 and the like can be shut off more reliably according to each alarm condition.

  FIG. 4 shows the structure of the database of the FT server. DB1 (211) is: 1) CONFIG 311 which is program information for performing monitoring control of the CPU 202 and PARAM 312 which is parameter information; 2) SYS 313 which is information related to abnormality and system abnormality associated with execution of the monitoring control program; ) Stores STORE 314, which is all the history information for three days, such as CONFIG, PARAM, and SYS, which is used when the PC 102 is activated.

  DB2 (212) is a register for the control calculation of the CPU 202, and is an I / O that stores CONFIG 321 as monitoring control program information and PARAM 322 as parameter information, a monitoring signal from the translator 103, and a control signal to the translator 103. O register 323 is stored.

  DB 3 (213) is an I / O register 331 that stores a monitoring signal from the translator 103 and a control signal to the translator 103, a SYS register 332 that stores information on the system abnormality register from the PLC 207, and an interface that outputs to the PLC 207. It has an INT register 333 for storing information related to the lock function.

  In the conventional DCS, since the controller is composed of a CPU and a memory, the storage area that can be secured as a register is limited, and the number of input / output interfaces (I / O) that can be accommodated is also limited. On the other hand, since the FT server 101 of this embodiment can include a large-capacity database, the number of translators that can be connected is not limited depending on the storage capacity.

  FIG. 5 shows a processing sequence by the FT server. Details of processing by the FT server will be described with reference to FIGS. 4 and 5. The translator 103 receives monitoring signals asynchronously (approximately at intervals of 50 to 100 ms) from individual devices and machines in the plant and stores them in a register.

  The CPU 203 operates in a cycle of 200 ms (monitoring control cycle), and performs four processes of monitoring signal input (IN), system abnormality monitoring (SYS), and interlock (INT) control signal output (OUT) every cycle. Is going. Therefore, monitoring signal input (IN), control signal output (OUT), system abnormality monitoring (SYS), and interlock (INT) are each executed five times during 1 s.

  In the system abnormality monitoring (SYS) process, the CPU 203 reads the information of the system abnormality register of the PLC 207 and stores it in the SYS register 332 of DB3 (213).

  In the supervisory signal input (IN) process, supervisory signal information stored in the register of the translator 103 is collectively received via the PLC 207 and stored in the I / O register 331 of DB3 (213). In the I / O register 331, the contents of the word (W) register of the PLC 207 are separately stored as an analog monitoring signal (AI), and the contents of the bit (B) register of the PLC 207 are stored as a digital monitoring signal (DI). .

  In the control signal output (OUT) process, the control signal information stored in the I / O register 331 of the DB 3 (213) is collectively transmitted via the PLC 207 and stored in the register of the translator 103. That is, the content of the analog control signal (AO) is stored in the W register of the PLC 207, and the content of the digital control signal (DO) is stored in the B register of the PLC 207.

  In the interlock (INT) process, in the input phase, the interlock information stored in the I / O 131 of the translator 103 is stored in the INT register 333 of the DB3 (213). Functions of safety instrumentation by executing the interlock function from the alarm signal (stored in the SYS 313) generated by the interlock function at the control computation level of the FT server 101 and the alarm signal from the I / O 131 level Strengthen.

  The CPU 202 operates in a 1 s cycle (control computation cycle), and for each cycle, the upper data input phase (Down-DIN), the lower data input phase (Up-DIN), the control phase (CONT), The data output phase (Up-DOUT) and the lower data output phase (Down-DOUT) are operated repeatedly.

  In the upper data input phase (Down-DIN), CONFIG 311 which is monitoring control program information stored in DB1 (211) and PARAM 312 which is parameter information are read into DB2 (212). The supervisory control program information is an operation program and calculation conditions necessary for control computation in the control phase, and is written in CONFIG 311 and CONFIG 321. The parameter information is an instruction input value processed by the control calculation and an operation setting value from the PC 102, and is read and written between the PARAM 312 and the PARAM 322.

  The lower data input phase (Up-DIN) is information on the monitoring signal and control signal stored in the DB3 (213) I / O register 331 (analog monitoring signal (AI) and digital monitoring signal (DI) from the PLC 207). Is read into the DB2 (212) I / O register 323. At this time, the monitoring signal is the latest monitoring signal (measured value) collected one cycle before in the control calculation cycle, and the control signal is the previous control signal (previous time) output one cycle before in the control calculation cycle. Output value).

  In the control phase (CONT), from the latest monitoring signal (measured value) in the DB2 (212) I / O register 323, parameter information (instruction input value) in the PARAM 322, and the previous control signal (previous output value). The current output value (latest control signal) is calculated. The latest control signal is overwritten in the DB2 (212) I / O register 323.

  In the upper data output phase (Up-DOUT), information after the control calculation stored in DB2 (212) is stored as history information in STORE 314 of DB1 (211). The DB2 (212) CONFIG 321 is written in the WS 110, and the DB1 (211) PARAM 312 is updated by the DB2 (212) PARAM 322.

  In the lower data output phase (Down-DOUT), the latest control signal information stored in the I / O register 323 of DB2 (212) is written to the I / O register 331 of DB3 (213). In this control signal, an analog control signal (AO) and a digital control signal (DO) output from the CPU 203 are recorded at the timing of the monitoring control cycle after one cycle of the control cycle.

  The CPU 201 operates asynchronously with the monitoring control cycle (100 ms cycle) and the control calculation cycle (1 s cycle). The CPU 201 includes an output phase (Dup) for transferring data from the lower CPUs 202 and 203 to the PC 102 via the LAN 104, an input phase (Ddown) for inputting data to the lower CPUs 202 and 203 from the PC 102, and a system. Abnormal processing (ALM) is executed in response to a request from the PC 102. In this embodiment, the operation is repeated approximately every 1 s, and separate requests are received from a plurality of PCs 102.

  In the PC 102 functioning as a console, control for individual devices and machines in the plant is transmitted to the FT server 101 as facility information and parameter information (Proc A). On the other hand, monitoring of devices and machines is received as history information from the FT server 101 (Proc B). In addition, the PC 102 is connected to the LAN 104, which is a general-purpose communication network, separately from the translator network 105 specialized for signal relaying. Monitoring control from the system is also possible (Proc C).

1 Distributed control system (DCS)
2,102 Computer (PC)
3 Controller 4 Gateway (GW)
5 Controller network 6, 106 Sensor 7, 107 Actuator 8, 108 External terminal 9, 109 External network 31, 131 Input / output interface (I / O)
32, 201-203 Processing unit (CPU)
100 Instrumentation System 101 FT (Fault Tolerance) Server 103 Translator 104 LAN
105 Translator network 110 Engineering workstation (WS)
130 Common Control Unit (COM)
204 Bus 205 Power supply (POW)
206 Battery (BATT)
211-213 database

Claims (5)

In an instrumentation system for monitoring and controlling a plant,
A computer connected to a communication network and executing a monitoring control program of the plant;
A translator connected to a monitoring element and a control element of equipment in the plant, transferring a monitoring signal from the monitoring element to a relay network, and transferring a control signal from the relay network to the control element;
A third CPU that receives the monitoring signal from the translator via the relay network, a second CPU that executes a monitoring program to generate monitoring information from the monitoring signal, and transmits the monitoring information to the communication network. A first CPU that transmits to the computer via the communication network, the first CPU receives control information from the computer via the communication network, and the second CPU receives a control program To generate the control signal from the control information, the third CPU transmits the control signal to the translator via the relay network, and the third CPU transmits a predetermined monitoring control cycle. The second CPU operates at a control calculation cycle different from the monitoring control cycle, and the first CPU operates at the monitoring control cycle. Instrumentation system, characterized in that the control cycle and the control operation cycle and a server running asynchronously. The instrumentation system according to claim 1, wherein the server is a dual FT (Fault Tolerance) server. A PLC inserted between the server and the relay network, and further detects a PLC that shuts off communication between the server and the translator when a failure or abnormality of the server or the equipment in the plant is detected. instrumentation system according to claim 1 or 2, characterized in that it comprises. In an instrumentation system for monitoring and controlling a plant, it is connected to a computer that executes the monitoring and control program for the plant, and monitoring elements and control elements of equipment in the plant, and transfers monitoring signals from the monitoring elements to a relay network And a server connected to a translator for transferring a control signal from the relay network to the control element,
A first CPU connected to a communication network to which the computer is connected, transmitting monitoring information to the computer, and receiving control information from the computer;
A monitoring program that generates the monitoring information from the monitoring signal from the translator; a second CPU that executes a control program that generates the control signal from the control information from the computer;
A third CPU connected to the relay network, receiving the monitoring signal from the translator, and transmitting the control signal to the translator ;
The third CPU operates at a predetermined monitoring control cycle, the second CPU operates at a control calculation cycle different from the monitoring control cycle, and the first CPU includes the monitoring control cycle and the monitoring control cycle. A server characterized by operating asynchronously with a control calculation cycle . Each of the first, second, and third CPUs has a duplicate database, and the first, second, and third CPUs and the database are connected by a duplex high-speed bus. The server according to claim 4 .

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