JP2581610B2 - Multiplexed controller control system - Google Patents

Description

The present invention relates to a multiplex controller control system,
For example, the present invention relates to a system suitable for a control system of a turbine plant such as a thermal power plant and a nuclear power plant.

[Conventional technology]

In conventional plant control, multiplexing of controllers is performed in order to increase reliability (Japanese Patent Application Laid-Open No.
JP-A-35202, JP-A-56-38601, JP-A-58-16
No. 301). For example, the controller of a gas turbine is tripled, the controllers are operated in parallel, and a control signal to be actually output is determined based on a majority decision logic or the like based on output signals of the controllers. I try to prevent control. In such a triple control system, it is most reliable to process all process signals related to control by the triple controller.

[Problems to be solved by the invention]

However, in order to input and output process signals to and from the controller, a process input / output device (hereinafter, referred to as PI / O) is required as an interface. When the number of process signals increases, the number of PI / Os increases, This will increase the mounting space and increase the cost.

In this regard, for example, an important process signal (hereinafter, referred to as an important signal) that may lead to a trip during the load operation of the gas turbine is input / output to / from the triple-system controller, and is necessary for continuing the load operation. For a process signal such as a sequence signal or a monitoring signal (hereinafter referred to as a common process signal or a common process input / output signal), a common process input / output processing controller separate from the above-mentioned triple system controller is provided. If input is made to the triple system controller via the input / output processing controller, the PI / O of the common process signal can be reduced to one third. In particular, since the common process signal generally has a larger number of signal points than the important process signal, it contributes to a reduction in the number of PI / Os.

However, when the common process input / output processing controller is made single as described above, if the common process input / output processing controller breaks down at the time of startup before starting the load operation,
Even if the triple controller is sound, the plant is stopped, and there is a problem in system reliability. Of course, it is not possible to monitor at the time of stoppage and start up.

An object of the present invention is to solve the above-mentioned conventional problems.In addition to reducing the number of PI / O points increased due to multiplexing of controllers, sufficient reliability can be obtained even before a load operation such as at startup. An object of the present invention is to provide a control system of a multiplexing controller that can be secured.

[Means for solving the problem]

To achieve the above object, the present invention comprises a multiplexed controller, a process input / output device connected to each of the controllers, and a self-diagnosis unit provided in each of the controllers. Each controller executes the same control operation based on a process input signal that is input from the control target via the process input / output device, and based on the result of the control operation, the control target executes the process input / output device. In a multiplexed controller system that outputs a process control signal via a multiplexed controller, the process input signal and the process control signal are directly connected to an important process signal that is indispensable for normal operation control of the controlled object and a normal operation control. Pre-divided into common process signals that do not affect The multiplexed controller inputs / outputs in parallel via the process input / output device, and the common process signal is transmitted to one of the multiplexed controllers via one common process input / output device and a switching circuit. Input / output is enabled, and the switching circuit selects one healthy controller based on a diagnosis result output from the self-diagnosis unit.

[Action]

With such a configuration, according to the present invention, the above object is achieved by the following operations.

Input / output processing of the common process signal is performed by one of the multiplexing controllers selected by the switching circuit. As a result, even if a failure occurs in any one of the controllers, the input / output processing can be performed by another healthy controller, so that the reliability of the control system other than the normal load operation such as the start control is improved. I do. Further, since one controller is selected by the switching circuit so as to input and output a common process signal, the number of process input / output devices used for the controller may be Torr or Zumel corresponding to one unit. Can be reduced.

〔Example〕

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

FIG. 1 shows a triple controller control system to which the present invention is applied. Controllers are A controller 1-1, B controller 1-2, C controller 1-3
Are operated in parallel, and each system performs the same control operation. Further, each system is independent, and as is well known, even if one system fails, the other two systems may fail.
The plant or the like as a control target operates normally by the process control output of the system controller. Further, each of the controllers 1-1 to 1-3 is provided with a failure diagnosis unit 2-1 and a failure diagnosis unit 2-1.
2-2, 2-3. This failure diagnosis means 2-1 and 2-2
For -3, a known method can be applied, for example, a method of self-diagnosis by a controller, a method of detecting a measurement deviation from a process, and the like can be applied. What is necessary is just to have.

Plant 3 such as gas turbine power plant to be controlled
Important process signals from the transmission lines 4-1 to 4-3,
The signals are input to the respective controllers 1-1 to 1-3 via a plurality of PI / Os 5-1 to 5-3. Here, the important process signal refers to a process signal that is indispensable for normal operation control of the plant 3. For example, a process signal that leads to a plant shutdown.In the case of a gas turbine plant, in addition to a signal that causes a trip or damage to the main engine, a master signal, a lubricating oil pressure signal, a speed signal, an exhaust temperature signal, a fuel control signal And so on. The process control output from each of the controllers 1-1 to 1-3 is output to the control target device of the plant 3 by a reverse route.

On the other hand, a process signal (common process signal) that does not directly affect the normal operation control of the plant is transmitted from the plant 3 to the switching circuit 23 via the transmission line 21 and the plurality of common PI / Os 22.
To the PI / Os 5-1 to 5-3 of the triple controllers 1-1 to 1-3 via the switching circuit 23. The switching circuit 23 includes an output controller changeover switch 24 and each PI / O5−
It is formed to include open / close switches 26-1 to 26-3 inserted into transmission paths 25-1 to 25-3 extending to 1 to 5-3.
The output controller changeover switch 24 is used for failure diagnosis means 2-1.
One healthy controller is selected based on signals 2-3. Each open / close switch 26-1 to 26
-3 correspond to the controllers 1-1 to 1-3, respectively, and when the controllers 1-1 to 1-3 fail, based on a command from the failure diagnosis means 2-1 to 2-3, It is open to the public. Note that, for example, in the case of a gas turbine plant, the common process input / output signal is a process signal related to sequence control, a process signal for monitoring control, and the like.

The common PI / O 22 processes the input common process input signal into a signal suitable for use in the control operation of each of the controllers 1-1 to 1-3, and conversely, the common process control signal is suitable for a device to be controlled. It has a common process signal input / output processing function for processing the processed signals. In the embodiment of FIG. 1, it is the selected one of the controllers 1-1, 1-2 or 1-3 that performs this function. When one of the controllers fails, the other sound controller performs the common process signal input / output processing instead. The processed common process input signal is input to another controller via the system bus 31. On the other hand, the common process control output is output to the plant 3 via the switching circuit 23.

As described above, according to the present embodiment, the input / output processing of the common process input / output signal is performed by one of the selected triple controllers 1-1 to 1-3, and the switching circuit 23 is provided so that the common process input / output signal is switched to any one of the selected triple controllers 1-1 to 1-3 for input / output.
Even if a failure occurs in any one of 1-3, processing can be performed by another sound controller. Therefore, the common process input / output processing devices are substantially multiplexed, and the reliability of the control other than the normal load operation such as the start control is improved. Further, since the input and output are switched by the switching circuit 23, the common PI / O 22 does not have to correspond to each of the controllers 1-1 to 1-3, and the number of points for one controller is sufficient. Smaller,
Cost can be reduced.

Note that the present invention is not limited to the above-described triple controller control system, and the same effects can be obtained even when applied to a dual or n-layer controller control system shown in FIG.

FIG. 3 shows a configuration diagram of a triple controller system to which a more specific embodiment of the switching circuit 23 is applied.
As shown, the switching circuit 23 includes an input / output switch 27 for switching between input and output of a common process input / output signal, a serial / parallel signal (S / P) converter 28, and a parallel / serial signal (P / S ) Converters 29-1 to 29-3 are added.

With this configuration, the input of the common process input / output signal is such that the input / output switch 27 of the switching circuit 23 is set to the input side. As a result, the common process input signal from the common PI / O 22 is once converted into a parallel signal by the serial / parallel converter 28. Then, the signals are distributed to three corresponding to the A, B, and C-system controllers 1-1 to 1-3, and converted into serial signals again by the parallel / serial converters 29-1 to 29-3. Controllers 1-1 to 1-
3 is input. The output is the process control output of each of the controllers 1-1 to 1-3, with the input / output switch 27 of the switching circuit 23 as the output side, and the output controller switch 24 for the A, B, and C controllers 1-1 to 1-1. 1-
Select one of the three. At this time, the selection of the output controller changeover switch 24 depends on the failure diagnosis means 2-1 to 2--2 of the A-system, B-system, and C-system controllers 1-1 to 1-3 as described above.
3, the output from the healthy controller is always selected. For example, if all the controllers 1-1 to 1-3 of the A system, the B system, and the C system are healthy, an arbitrary healthy controller of the A system, the B system, and the C system is selected. If the A system is abnormal and the B system and the C system are sound, the output controller changeover switch 24 selects one of the sound B system and the C system. In this way, by operating normally as a whole system, it becomes possible to continue normal operation without causing disturbance in the plant.

〔The invention's effect〕

As described above, according to the present invention, input / output processing of a common process signal is performed by one of the selected multiplexing controllers, and a switching circuit is provided to input / output the common process signal. Since the input and output are switched to any one of the selected multiplexing controllers, even if a failure occurs in the controller, processing can be performed by another healthy controller. Therefore, the common process input / output processing devices are substantially multiplexed, and the reliability of the control other than the normal load operation such as the start control is improved.

In addition, since switching is performed by the switching circuit for input / output, the common PI / O does not have to correspond to each controller, and the number of points for one controller is sufficient, so that mounting space is reduced and cost is reduced. be able to.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a triple controller controller system according to one embodiment of the present invention, FIG. 2 is a configuration diagram of an n-layer controller control system of another embodiment of the present invention, and FIG. FIG. 9 is a configuration diagram of another embodiment related to the switching circuit of the embodiment. 1-1 to 1-n Controller 2-1 to 2-n Failure diagnosis means 3 Plant 5-1 to 5-n Process input / output device (PI / O) 22 ... Common PI / O, 23 ... Switching circuit, 24 ... Output controller switch, 27 ... Input / output switch.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sadao Yanagita 5-2-1 Omikacho, Hitachi City, Ibaraki Prefecture Inside the Omika Plant, Hitachi, Ltd. (72) Inventor Tadahiko Iijima 5-2-2 Omikacho, Hitachi City, Ibaraki Prefecture No. 1 Hitachi, Ltd. Omika Plant (72) Inventor Shigeki Adachi 5-2-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi, Ltd. Omika Plant (56) References JP-A-58-75201 (JP, A) JP-A-58-75202 (JP, A) JP-A-59-2102 (JP, A) JP-A-56-35202 (JP, A) JP-A-59-62903 (JP, A)

Claims (2)

(57) [Claims] 1. A multiplexed controller, a process input / output device connected to each controller,
Self-diagnosis means provided in each of the controllers, wherein each of the controllers executes the same control operation on the basis of a process input signal input from the control target via the process input / output device. A multiplexing controller system for outputting a process control signal to the control target via the process input / output device based on a result of the control operation, wherein the process input signal and the process control signal An important process signal that is indispensable for operation control and a common process signal that does not directly affect normal operation control are previously divided, and the important process signal is input and output to the multiplexed controller. Input / output in parallel via the device, and one common processor for the common process signal. Access to each of the multiplexed controllers via a processor input / output device and a switching circuit, wherein the switching circuit selects the one healthy controller based on a diagnosis result output from the self-diagnosis unit. A multiplexed controller control system characterized in that: 2. The multiplexing apparatus according to claim 1, wherein, among the controllers, a controller which performs input / output processing of a common process signal outputs the processed common process input signal to another controller through a system bus. Controller control system.