JPS61204701A - Redundancy system - Google Patents

Abstract

PURPOSE:To eliminate an influence of drawing to a plant by providing an operating means which is operated prior to drawing from a system and sends out a prescribed signal to a backup device. CONSTITUTION:On a control arithmetic unit 1, a self-diagnosing part 11 is provided, whether a control function of itself is normal or not is always monitored, and when an abnormality has been detected, a contact 12 is opened. As a result, a relay 14 becomes non-exciting, its contact 15 becomes a state as shown in the figure, and an abnormality signal SFi is transferred to a backup device 2 through a line 7i. When an abnormality is detected from a state of the line 7i, the backup device 2 discriminates by which control arithmetic unit it has been caused, and outputs a signal SBi for showing a fact that the unit is in the course of backup, to the corresponding AND gate 4i. In this case, the AND gate 4i is opened, switches 5i, 6i become a state reverse to those which are shown in the figure, and the backup by the backup device 2 is executed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides n control calculation devices (n≧1) that can be individually inserted into and removed from a system and that perform predetermined control calculations. The present invention relates to a redundant system comprising: a bank-up control/arithmetic unit that replaces the function of one of the control/arithmetic units when an abnormality occurs or when one of the control/arithmetic units is removed from the system.

[Conventional technology]

When the individual control processing units constituting a redundant system are made of card-shaped printed circuit boards, for example, and are of plug-in type that can be attached to and detached from the system, they are often pulled out inadvertently. In such cases, conventional methods have been adopted in which the state change is notified to a backup control arithmetic unit (also simply referred to as a backup device) using a contact signal, and the backup device receives this and performs a predetermined backup operation. Common.

[Problem that the invention seeks to solve]

However, with this method, there is a time delay between when the control processing unit is pulled out and when it enters the backup mode, and during this time, no signal is given or the signal is in an undefined state. There is a problem in that it has a negative impact on

[Means for solving problems]

A signal sending operating means for sending a predetermined signal to the bank up device prior to pulling out the redundant system is provided in each control arithmetic device constituting the redundant system.

[Effect]

When removing one of the control computing units from the system,
Immediately before that, the operating means is operated to send a predetermined signal to the bank-up device, and the necessary operation for backup is performed, so that the output signal to the controlled object such as the plant is not lost; Avoid adverse effects on controlled objects.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 1A is a schematic diagram showing a specific example of the control calculation device in FIG. In FIG. 1, 1 (II to 1□) is a control calculation device, 2 is a backup control calculation device (backup device), 3 is a plant (control object), 4 (4+ to 4.,
) is an and gate, 5, ~5, 1, 6. ~67 is a switch, 7□ (i is any integer that satisfies 1≦i≦n; the same applies hereinafter) is a notification line that notifies the status of the control processing unit including the abnormal signal SF, and 85 is a backup in progress. 91 is an input signal line, 10□ is an output signal line, and L is a transmission line. In addition, in FIG. 1A, 1
1 is a self-diagnosis section, 12 and 13 are switches, 14 is a relay, and 15 is a contact point of the relay 14.

The operation will be explained below with reference to these figures.

The control calculation device 1i takes in the state of the plant 3 via the input signal line 9i, performs predetermined control calculations, and outputs the results on the output signal line 10. It is sent to plant 3 via. The backup device 2 monitors the operating state of the control processing device 1 via the transmission line L, collects data, and prepares to shift to a backup mode at any time. In addition, the control calculation device 1 is provided with a self-diagnosis section 11 as shown in FIG. Open as follows. As a result, the relay 14 becomes de-energized, and its contact 15 becomes the state shown in the figure, and an abnormality signal SF is generated.

is transmitted to the backup device 2 via line 7. On the other hand, when normal, contact 12 closes and relay 14
is excited, so a normal signal is transmitted through its contact 15. That is, since signals of 0'' and ''v2' volts appear on line 7° depending on normality and abnormality, respectively, the backup device 2 determines normality and abnormality by monitoring a predetermined point X on this line. When the bank up device 2 detects an abnormality from the state of the line 7i, it determines which control arithmetic device caused the abnormality, and sends a signal SB indicating that backup is in progress to the corresponding AND gate 41 in FIG. Output. At this time, an abnormality signal SF is sent from the corresponding control calculation device 1.

Since is being output, the AND gate 4□ opens, which causes the switches 54 and 6i to be in the opposite state to that shown in the figure.
Backup is performed by the backup device 2.

The above has mainly explained the case where the self-diagnosis results in an abnormality, that is, the case where the switch 12 is opened.
In addition, even if the power to the control calculation device 1 is lost for some reason, or if the control calculation device 1 is removed from the system, the operation is the same as described above.

In other words, in the former case, relay 14
is de-energized, and in the latter case switch 1
Since switch 13 is opened before switch 2 is opened, it can be seen that each operates in the same manner as described above. Particularly in the latter case, a new switch 13 is installed, and the switch 13 is
By operating the backup device 2 to start the backup operation in advance, the negative impact on the plant due to the removal of the control arithmetic device is eliminated.

〔Effect of the invention〕

According to this invention, by providing in each control arithmetic device constituting the redundant system an operating means that is operated and sends a predetermined signal to the backup device prior to pulling out the control arithmetic device from the system, the control arithmetic device It becomes possible to start the backup operation by the backup device before the device is actually pulled out, and this brings about the advantage that the influence of this withdrawal on the plant to be controlled can be eliminated.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 1A is a schematic diagram showing a specific example of the control calculation device shown in FIG. Description of symbols 1 (1, to 13)...Control calculation device, 2...Backup control calculation device, 3...Plant (control target), 4 (4, to 4.)...And gate, 5I~5
,. 61-6. ．． 12.13--Switch, 7. ~7n・
...Notification line, 81-8. l...backup signal line, 91~9ka...input signal line, 1o...
・Output signal line, 11... Self-diagnosis section, 14...
Relay, 15...Contact of relay 14, L...Transmission line. Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyoshi Matsuzaki 1111A

Claims (1)

[Claims] A plurality of control calculation devices that can be individually attached to and removed from the system and perform predetermined control calculations, and a backup system that can be used in the event that any one of these control calculation devices malfunctions or is removed from the system. In the redundant system, each of the control calculation devices is provided with operating means that is operated to send a predetermined signal to the backup device prior to extraction from the system, and the control calculation device is connected to the system. A redundancy system characterized in that the start point of the backup operation is accelerated by operating the operating means before pulling out the backup operation.