JPS5841534B2 - central control unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a central control device that provides a control command signal to, for example, a remote monitoring and control device and controls a controlled device by the remote monitoring and control device.

In recent years, a system has been adopted that centrally monitors and controls each control device at a controlled facility (hereinafter referred to as a centralized control system) using a remote monitoring and control device (hereinafter referred to as TC) that monitors and controls equipment in a remote location via a transmission line. This greatly contributes to labor savings and safety improvements.

Recently, such systems have become increasingly large-scale, and there are many cases in which monitoring and control are performed by duplicate computers.

FIG. 1 shows a typical schematic configuration diagram of a centralized control system with dual command devices.

In FIG. 1, reference numerals 1 and 2 designate command devices having the same configuration for supplying control command signals to the TC, which are mainly computer-based devices.

3 is a mode control device that controls the operation mode of the command devices 1 and 2; 4 is a TC switching device that switches the control command signal from the command device 1.2 and supplies it to the TC; 5-1.・・・
・, 5-N is the TC control center side, 6-1. ..., 6-N
indicates the controlled station side of the TC.

From the command devices 1 and 2, TC (control center side) 5-1.・
..., 5-N, but when actually supplying control command signals to the TC, make sure that the control command signals of both command devices 1 and 2 do not overlap. A switching circuit is required to switch to

In FIG. 1, this is done by the TC switching device 4.

When the operation mode in which output to the TC is permitted is called an online mode, the TC switching device 4 must be switched so that the control command signal of the command device in the online mode is supplied to the TC.

In other words, if the hardware and software of both command devices 1 and 2 are normal, the command device designated for online mode will output a control command signal to the TC.
Switch the switching device 4.

If either command device stops or malfunctions,
If the other command device detects the failure and switches the TC switching device 4 so that it outputs a control command signal to the TC, the control command signal from the stopped or malfunctioning command device will be erroneously supplied to the TC. It never happens.

However, if one command device stops and the other command device in online mode fails and stops, the TC switching device 4 remains switched to the abnormal command device, and the TC switching device 4 remains switched to the abnormal command device. An abnormal command signal is supplied to the TC, and this abnormal signal may cause the TC to control each control device at the controlled station.

In other words, if the hardware and software of either command device are in a normal state, it can be put into online mode and output a normal control command signal, but if both command devices are abnormal, the command device will issue an incorrect control signal. There is a possibility that the command signal is supplied to the TC switching device 4.

Therefore, if such a case occurs (both command devices are stopped), the operator has no choice but to take emergency measures such as turning off the power to each TC, which places an extremely heavy burden on the operator, and also prevents the operator from making mistakes. There was a possibility that the control command would be supplied to the TC.

In addition, even if both command devices 1 and 2 are not stopped, the above-mentioned error can still occur in the transient state after the command device in online mode stops and until the other command device is switched to online mode. There was a possibility that the control command signal was sent to the TC.

This invention was made in consideration of these circumstances,
The purpose is to provide a highly reliable central control unit that can always switch to the online mode command unit among multiple command units without causing the control unit to malfunction. be.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a configuration diagram showing an embodiment of the present invention.

In FIG. 2, 10 and 20 are the command devices 1 and 2 in FIG.
It is a command device similar to

10-1, 10-2,..., 10-N, 10-R
is one of the control command signals that the command device 10 supplies to the TC.
This is a group of bits that make up a set.

The N bits of the above 10-1゜10-2,..., 10-N represent the contents of the control command signal, and 10-R is ``2'' N.
This is a ready signal bit that indicates whether the bit is valid.

The above control command signals 10-1, 10-2,..., 1
0-N is valid only when the ready signal 10-R is on.

Similarly 20-1.20-2. ..., 20-N. 20-
R is a bit group constituting one set of control command signals that the command device 20 supplies to the TC, and the meanings of each bit are as follows: 1O-LIO-2°..., 10-N, 10-R. It's the same.

Reference numeral 30 denotes a mode control device similar to the mode control device 3 in FIG. 1, and a keep relay X, which will be described later, is provided inside.

40 is a command switching device, and this command switching device 40 receives control command signals 50-1, 50-2, . . . supplied from the command devices 10 and 20 to the TC (control center side) 50.
, 50-N, and 50-R.

50-1 above. 50-2. ..., 50-N, 50-
R is one of the control command signals supplied to the TC (control center side) 50
A group of bits forming a set, and the meaning of each bit is as described above in 10-1.10-2,..., 10-N, 10-R.
is the same as

Xa (Xa,, Xa2.-, XaH, XaR) and x
bcxb,,xb2. ..., XbN, XbR) is one keep relay X provided in the mode control device 30.
Normally open contacts and normally closed contacts.

The keep relay When received, it is reset, that is, the normally open contact Xa is opened and the normally closed contact Xb is closed.

In addition, in reality, the normally open contact Xa and the normally closed contact xb are 1
Since there are too many contacts for each keep relay X, appropriate contact amplification is required, but to simplify the explanation, one keep relay X is used.

Ya is a state contact that is closed when the command device 10 is in the online mode, and naturally opens when the hardware or software of the command device 10 is abnormal.

Za is a state contact that is closed when the command device 20 is in the online mode, and naturally opens when the hardware or software of the command device 20 is abnormal.

60 is the controlled center side of the TC controlled by the TC (control center side) 50.

Next, the operation of this device in the above configuration will be explained.

For example, when the command device 10 is in the online mode, the command device 10 supplies a pulse-like signal to the keep relay X as soon as it is ready to set the keep relay X, which has been in the reset state until then.

That is, the normally open contact Xa is closed, and the normally closed contact xb is opened.

Therefore, the control command signals 10-1, 10-2,...
, 10-N are supplied to the command switching device 40.

Then, when the status contact Ya is closed, the ready signal 10-R
is supplied to the command switching device 40.

As a result, the control command signals 10-1, 10-2,...
・, 10-N becomes valid, and the TC is transmitted from the command switching device 40.
(Control center side) Control command signal 50-1.50-2 to 50
,...,50-N.

50-R is supplied.

As a result, TC (control center side) 50 becomes TC (controlled center side)
60 control is started.

However, when the hardware or software of the command device 10 is abnormal, the status contact Ya remains open.
Control command signals 10-1, 10-2.

. . , 10-N becomes invalid as an abnormal command signal.

In this case, the mode control device 30 switches the online mode from the command device 10 to the command device 20.

As a result, the normally open contact Xa becomes open and the normally closed contact xb becomes closed.

Therefore, control command signals 20-1, 20-2°, . . . , 20-N are supplied from the command device 20 to the command switching device 40.

Then, when the status contact Za is closed, the ready signal 10-R
is supplied to the command switching device 40, and the control command signal 10-1
゜10-2,...,10-N become effective, and TC(
The control center side) 50 starts controlling the TC (controlled center side) 60.

However, if there is an abnormality in the hardware or software of the command device 20, the status contact Za remains open, so the control command signal of the command device 20 is transferred to the command switching device 40.
is not supplied.

Therefore, if an abnormality occurs in both command devices 10 and 20, control commands from both command devices 10 and 20 will no longer be supplied to the TC (one control side) 50.

Thus, when a pulse signal is supplied from the command device 10 to the keep relay X, the normally open contact Xa is closed and the normally closed contact When supplied, the normally open contact Xa is opened and the normally closed contact T from the device
Commands can be reliably given to C (control center side) 50.

In addition, the status contact that responds to the presence or absence of an abnormality in the hardware or software of the command device turns off the ready signal, and the N bit signal supplied from the command device in online mode to the TC (control center side) 50 is turned off. Since the control command signal is determined to be valid or invalid, the configuration is simple and no abnormal signal is supplied to the TC (control center side) 50, thereby preventing malfunction of the TC (control center side) 50. It can be prevented.

Therefore, even if both command devices fail, an erroneous signal will not be supplied to the TC (control center side) 50 from the abnormal command device.

Also, no erroneous signal is supplied to the TC (control center side) 50 even in a transient state after the command device in online mode stops and until another command device is switched to online mode.

Therefore, not only can it be manufactured at a low cost with a simple configuration, but
The reliability of the device can be improved.

In addition, as a device for preventing an abnormal signal from being supplied to the TC, for example, the normally open contact Xa and the normally closed contact It is also possible to use a device that operates only in online mode.

In this case, the number of relays is twice as large as that of the embodiment described above, and the structure is complicated.

Further, in the above embodiment, a computer-based device is shown as the command device 10.20, but other command devices such as an arithmetic device may be used.

Furthermore, although a TC is shown as a control device, other devices may be used as long as they can be commanded and operated by a command device.

Further, in the embodiment described above, the command switching device is composed of relay contacts, but it may also be composed of semiconductors or the like.

Further, although there was one TC in the above embodiment, the present invention is also effective in a system having a plurality of TCs as shown in FIG.

Further, in the above embodiment, for one bit of the ready signal, Ya
, Za is provided, but signal 1 has the same meaning as the ready signal.
It is of course possible to set conditions such as Ya and Za for bits to several bits.

Further, although the above embodiment has been described using two command devices, the present invention can be easily applied even if there are three or more command devices.

Specifically, after switching the control command signals from the plurality of command devices, a condition such as Y at Z a may be set for the ready signal.

As detailed above, according to the present invention, the mode control device performs switching so that a control command signal can be supplied from the command device to the control device only when the command device in the operation mode is normal. , it is possible to provide a highly reliable central control device that can give control command signals without causing the control device to malfunction.

[Brief explanation of the drawing]

FIG. 1 is a typical schematic configuration diagram of a centralized control system with dual command devices, and FIG. 2 is a configuration diagram showing an embodiment of the present invention. 10.20... Command device, 30... Mode control device, 40... Command switching device, 50...
...TC (control center side), 60...TC (controlled center side), X...Keep relay YayZa...Status contact.

Claims (1)

[Claims] 1 Specify a control device that controls a controlled object, multiple command devices that give control command signals indicating control contents to this control device, and a command device that controls the operation mode of these command devices and can be placed in online mode. a mode control device that switches a command device specified by the mode control device to an online mode so that the control command signal can be transmitted to the control device side, and the command device that is in the online mode is in a normal state. and a device for detecting whether the control device is in an abnormal state and blocking a control command signal from the command device transmitted to the control device through the switching device when the abnormal state is detected. central control unit.