JP6837413B2 - Monitoring and control equipment for plant equipment - Google Patents

Description

The present invention relates to a monitoring control device for plant equipment in a nuclear power plant or the like, and more particularly to a duplex control system for mutual backup of the monitoring control device.

Conventionally, as a switching method of a redundant control system in which the control unit used for plant monitoring control is duplicated and system switching is performed, one control device is operated and the other control device is operated as standby, and the operating system control device is operated. When switching from to the standby system control device, the input / output device receives a hold command, and during this switching period, the I / O (Import / Output) unit output of the input / output device is put into the hold state, and after the switching is completed, the operation is switched to operation. A technique for releasing an output hold of a plurality of I / O units by receiving a hold release command from a control device is disclosed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 7-56763

However, the technique shown in Patent Document 1 has a problem that when the system is switched from the active system control device to the standby system control device, both systems are in the standby state, temporarily in the non-output state, and no signal is output. is there.

The present invention has been made to solve the above problems, and provides a monitoring and control device for plant equipment that outputs a stable signal without an output state even when the system is switched. With the goal.

The plant equipment monitoring and control device of the first invention is the above-mentioned first system monitoring and control device of a duplex control plant equipment in which a connection plant equipment is provided in common to the first system control device and the second system control device. When the system control device detects an abnormal state and the determination unit determines that it is abnormal, the system control device outputs a control switching switching signal from the first system control device to the second system control device, and at the same time, outputs a control switching signal of the first system control device. The output OFF signal is output to the delay circuit unit, the delay circuit unit delays the output timing within a preset period, and the second system control device determines that the input switching signal is correct. After the determination, the switching from the first system control device to the second system control device is performed within the preset period.

Since the monitoring control device for the plant equipment according to the present invention adopts the above configuration, it is stable without falling into a no-output state even when switching from the first system control device to the second system control device. It has the effect of outputting the signal to the plant equipment.

It is a block diagram which shows the monitoring control apparatus of the plant equipment of Embodiment 1. FIG. It is a figure which shows the operation timing of Embodiment 1. FIG.

Embodiment 1.
Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings. In FIG. 1, the monitoring control device 100 of the plant equipment includes a first system control device 50 (hereinafter abbreviated as the first system 50) and a second system control device 50A (hereinafter abbreviated as the second system 50A). Has been done. In the first embodiment, the first system 50 is used as a control system and the second system 50A is used as a standby system to form a redundant control system that backs up each other. As shown in FIG. 1, the plant equipment 40 receives an output signal from the output unit 3 of the first system 50 and an output signal from the output unit 3A of the second system 50A. A central control unit 60 is provided above the first system 50 and the second system 50A, and the entire plant facility is monitored and controlled by the central control unit 60.

The first system 50 generates a signal in the output signal generation unit 1, and the output connected to the output signal generation unit 1 and the all-point open switching unit 2 (ON / OFF switching unit 2) output in the output mode. A signal is transmitted from the unit 3 to the plant equipment 40. When an abnormal state occurs in the first system 50 for some reason, the abnormality detection unit 6 detects this state, and the determination unit 7 determines whether or not it is caused by noise or the like, and after determining that it is abnormal, the signal switches the system. It is transmitted to the control unit 4. The system switching control unit 4 of the first system 50 outputs a system switching signal 10 to the system switching control unit 4A of the second system 50A, and starts an operation of switching from the first system 50 to the second system 50A as described later. To do. Here, the output of the first system 50 and the mode switching (ON / OFF switching) of the all-point open switching unit 2 are performed by the signal of the system switching control unit 4, and this signal is input to the delay circuit unit 5. This adjusts the mode switching timing. The delay circuit unit 5 operates the delay circuit only when the output and the all-point open switching unit 2 switches from the output to the all-point open (ON → OFF). Further, when the second system 50A described later functions as a control system, the delay circuit unit 5A operates in the same manner.

The output signal generation unit 1A, output and all-point open switching unit 2A, output unit 3A, system switching control unit 4A, delay circuit unit 5A, abnormality detection unit 6A, and determination unit 7A of the second system 50A are the first system 50, respectively. Since the configuration is provided in the same manner as in the above, and the details thereof are the same as those in the first system 50, the description thereof will be omitted.

Next, in the monitoring control device 100, the operation of switching from the first system 50 of the control system to the second system 50A of the standby system will be described. In the period RA of FIG. 2, which will be described later, in which the first system 50 is operating normally, the signal generated by the output signal generation unit 1 is transmitted from the output set to the output mode and the all-point open switching unit 2 to the output unit 3. A device having a large inertia, such as a cooling water flow rate adjusting valve, a flow path switching valve, a pump electric motor, a blower electric motor, etc., which is a plant device 40 and does not operate quickly within the following delay time (predetermined time). It is output to. When the abnormality detection unit 6 detects the failure of the first system 50 and the determination unit 7 determines whether the abnormality is correct or not and then determines that the abnormality is abnormal, the system switching control unit 4 determines from the first system 50 to the second with respect to the second system 50A. The switching signal 10 for control switching is output to the system 50A. At this time, in order to stop the output from the output unit 3 of the first system 50, the system switching control unit 4 sends a signal for setting the output and the all-point open switching unit 2 to the all-point open mode (output OFF) to the delay circuit unit 5. Output. As an operating characteristic, the delay circuit unit 5 performs a delay operation only when switching from the output mode to the all-point open mode. Therefore, the delay circuit unit 5 delays the timing at which the output of the output unit 3 is turned off. In the first embodiment, a delay is performed between 10 msec and 20 msec.

In the second system 50A, the determination unit 7A determines whether the switching signal 10 input from the first system 50 is correct, for example, not noise, and after determining that the switching signal 10 is correct, the system switching control unit 4A outputs the signal. The signal set to the mode is output to the delay circuit unit 5A. The delay circuit unit 5A of the second system 50A is a switch from the all-point open mode to the output mode, and since delay is not performed as its operation characteristic, the output of the first system 50 is maintained from 10 msec. Within a period of 20 msec, the second system 50A switches from the standby system to the control system, and a signal is output from the output unit 3A to the plant equipment 40.

The main part of the above operation will be described with reference to the timing chart of FIG. ST is an abbreviation for step.
ST1. The first system 50 operates normally in the period RA, but when the abnormality detection unit 6 detects an abnormality, the determination unit 7 determines the abnormality, and then the system switching control unit 4 sends a switching signal 10 to the second system 50A. At the same time as outputting, a signal for setting the output and the all-point open switching unit 2 to the all-point open mode is output. The delay circuit unit 5 delays the output from the output unit 3 for a period of 10 msec to 20 msec shown in RC.
ST2. The output of the output unit 3 is turned off after the delay time of 10 msec to 20 msec elapses, but as shown in ST6, the output of the output unit 3 is continued until the end of the period RC.
ST3. The system switching control unit 4A of the second system 50A is turned on, and the determination unit 7A determines that the switching signal 10 from the first system 50 is not an erroneous signal, and the output and all-point open switching unit 2A are all points. Outputs a signal from open mode to output mode.
ST4. The delay circuit unit 5A operates without delaying the transmitted signal.
ST5. The second system 50A operates from the standby system to the control system, and outputs a signal from the output unit 3A to the plant equipment 40 as shown in the period RB.
ST6. As shown in period RA + period RC + period RB, the output signal to the plant equipment 40 is continuously output.

As described above, the monitoring control device 100 according to the first embodiment adopts a configuration in which the output signal of the control system is delayed by the delay circuit unit 5 for a predetermined time of 10 msec to 20 msec when switching from the control system to the standby system. Therefore, there is an effect that the output signal from the duplicated monitoring control device 100 to the plant equipment 40 does not fall into a no-output state even when the system is switched, and a stable signal is output. It also has the effect of preventing erroneous switching due to erroneous signals such as noise.

In the present invention, the embodiments can be appropriately modified or omitted within the scope of the invention.

1,1A output signal generation unit, 2,2A output and all-point open switching unit, 3,3A output unit, 4,4A system switching control unit, 5,5A delay circuit unit, 6,6A abnormality detection unit,
7,7A Judgment unit, 50 1st system control device, 50A 2nd system control device,
100 Monitoring and control device.

Claims (3)

In the monitoring control device of the dual control plant equipment provided with the plant equipment connected in common to the first system control device and the second system control device, the first system control device detects an abnormal state and causes a determination unit. When it is determined to be abnormal, a control switching switching signal is output from the first system control device to the second system control device, and a signal for turning off the output of the first system control device is output to the delay circuit unit. The delay circuit unit delays the output timing within a preset period, and the second system control device determines that the input switching signal is correct, and then within the preset period. A monitoring control device for plant equipment in which a switch from the first system control device to the second system control device is performed. Claim 1 in which the first system control device and the second system control device have the same components, the first system control device is a control system, and the second system control device is a standby system. The monitoring and control device for the plant equipment described in. The monitoring and control device for plant equipment according to claim 1 or 2 , wherein the predetermined period is 10 msec to 20 msec.

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