JP3298239B2 - Equalization method for redundant control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided with a dual operation system for a working controller and a standby controller. The present invention relates to an equalization method for keeping all data including a program held by an active control device and a standby control device equal in a redundant control system having a control device such as that described above.

[0002]

2. Description of the Related Art FIG. 1 is a block diagram showing a system according to an embodiment of the present invention. The means 2A in the figure does not exist conventionally. In FIG. 1, 1 is an active PC (active PC), 2 is a standby PC (standby PC), 8 is a control target, and 7 is an input / output interface of the redundant PC 1 and 2 for the control target 8 as a common input / output interface. An output device 4 is a management personal computer of the system shown in FIG.
And a common transmission path for connecting the management personal computer 4 and the like. Reference numeral 6 denotes an equalizing transmission line (also referred to as a synchronous bus) as a data transfer path for keeping the data held by the two always equal (that is, equalizing), provided between the active PC 1 and the standby PC 2. This is a loader for storing programs and the like in the PCs 1 and 2.

In FIG. 1, a duplicated PC is shown.
Conventional equalization of 1 and 2 is realized by the following procedure. Before the operation, the same program and definition data are transferred from the management personal computer 4 via the transmission line 3 or directly using the loader 5 to the active PC 1 and the standby PC 2.

When the operation starts, the operating PC 1 exchanges data with the input / output device 7 and executes control on the control target 8. Immediately after the standby operation of the standby PC 2 is started, fixed data is transferred from the active PC 1 to the standby PC 2 using the transmission path 6 for equalization. After the completion of the above, dynamically changing variable data is transferred from the active PC 1 to the standby PC 2 at regular intervals using the equalization transmission line 6.

[0005] The active PC 1 and the standby PC 2 mutually monitor using the transmission line 3. If the active PC 1 becomes abnormal, abandon the operating right, and if the standby PC 2 is normal, the standby PC 2 is newly switched to the active side to execute control.

[0006]

However, the above-described dual control system has the following disadvantages. When changing the program or the definition data, the changed program or the definition data must be transferred from the management personal computer 4 or the loader 5 to the two PCs 1 and 2 in the same manner as the above-described program loading before the operation. No.

[0007] After switching due to an abnormal condition and replacing the PC on the standby side, it is necessary to transfer programs and definition data from the management personal computer or loader to the standby PC again. Therefore, the present invention solves the above problem,
It is an object of the present invention to provide a method of equalizing a redundant control system in which a program or definition data can be easily changed or an abnormal PC can be exchanged in the same manner as a single PC control system without being aware of redundancy in the redundant control system. Make it an issue.

[0008]

In order to solve the above-mentioned problems, according to the equalization method of the present invention, a standby-side control device (stand-by PC 2 or the like) and an operating-side control device in which a program and fixed data are stored in advance. Device (such as the operating PC 1), the operating control device always controls the control target (8, etc.), and the standby control device monitors at regular intervals for any abnormalities in the operating control device. Redundant control in which the variable data is transferred from the active control device to itself via the value transmission line 6 and the like, and when the active control device is abnormal, the standby control device controls the control target in place of the active control device. In the system, the standby-side control device causes the active-side control device to transfer all data including the program to itself when the power is turned on and reset (via the active-side all data copying unit 2A and the like). In both cases, during the above-mentioned monitoring of the operation-side control device, it is also checked whether or not the program or the fixed data of the operation-side control device has been changed (via the operation-side all data copying means 2A or the like). All data including the program is transferred from the active control device to itself.

Further, according to the equalizing method of the second aspect, the first aspect
In the equalization method described in 1 above, the standby-side control device checks whether the program or fixed data of the active-side control device has been changed (via the active-side all data copying means 2A or the like) during the monitoring of the active-side control device. Is checked, and when this change is made, all data including the program is transferred to itself from the operating control device.

[0010]

When the power of the standby PC is turned on and reset, and when the program and definition data of the active PC are changed, the standby PC transfers all data including the program of the active PC to itself, so that the standby PC can operate before the system operation or When the program is changed, it is only necessary to load the program and the definition data into the operating PC.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the present invention, in FIG.
2, an operation-side all data copying means 2A is provided. The copy unit 2A is a partial function unit when it is considered that the function unit related to the present invention among the functions of the standby PC 2 is shared and executed.

FIG. 2 is a flowchart showing the operation of the standby PC 2 when the power is turned on or reset, according to the present invention.
1 to 110 indicate the steps. FIG. 3A shows a protocol (communication procedure) for mutual monitoring between the PCs 1 and 2, and FIG. 3B is a flowchart of an operation in which the standby PC 2 confirms whether or not the operating right has been moved based on the mutual monitoring. , 3
01 to 305 indicate the steps.

Next, FIG. 2 will be described first. When the power supply of the standby PC 2 is turned on during the normal operation of the operating PC 1, the standby PC 2
Determines in step 101-103 that it is the standby controller of the duplex system. That is, the standby PC 2 first performs initialization (101), checks whether or not the equalization transmission line 6 as a synchronous bus exists (102). It operates (109). However, if the equalization transmission line 6 exists at step 102 (branch Y), it is checked whether or not the operating PC 1 exists (103). If the active PC 1 does not exist (branch N), it operates as the active control device (108). If the active PC 1 exists (103, branch Y), it operates as the standby control device. Confirm that there is. Then, using the message communication function of the equalization transmission line 6, the active PC 1 is requested to transfer data (10
4) Receive all data including program and definition data (105, 106). Then, when the reception of all data is completed (106, branch Y), the operation state as the standby-side control device of the duplex system is entered (107).

As shown in FIG. 3A, the mutual monitoring between the active PC 1 and the standby PC 2 is performed by the active PC 1 via the transmission path 3 to transmit the operation right confirmation 9, and the standby PC 2 is similarly transmitted to the transmission path 3. This is realized by transmitting the operation right confirmation response transmission 10 via the. Thus, the active PC 1 and the standby PC 2 can know each other's presence and state.

A change in the program or definition data on the operating PC 1 can also be added to this transmission to make the standby PC
2 can know. That is, as shown in FIG. 3B, the standby PC 2 analyzes the transmission data of the operation right confirmation 9 from the operation PC 1 at this time. When it is determined by this analysis that the operating PC 1 has abandoned the operating right (301, branch Y), a response to the effect of obtaining the operating right is activated for the confirmation response 10 of FIG. 3A (302). Then, the operation is started as the active control device in place of the active PC 1 (304).

On the other hand, when it is determined in step 301 that there is no relinquishing of the operating right (branch N), a response indicating that there is no relinquishing of the operating right is started for the confirmation response 10 (303).
Further, it is checked whether or not the program or the definition data has been changed (that is, a change in the state of the working PC 1) on the side of the working PC 1 (305). Operating PC after moving to 104
1 requests the transfer of all data. As a result, the program / definition data becomes the same as that of the active PC 1.

It is to be noted that the active side all data copying means 2A shown in FIG.
Function corresponds to steps 104 to 106 in FIG. 2 and step 305 in FIG.

[0018]

According to the present invention, at power-on or reset, if the control unit (PC) determines that it is the standby-side control unit of the duplex system, all data including the program is copied from the operation side. When the dual system is started up, the program and definition data are stored only on the active side, and then all the stored data on the active side is copied to the standby side just by turning on the power on the standby side. There is no need to separately store the same program and definition data as those on the operating side by hand, and this has the effect of simplifying the startup of duplication and replacement of the PC.

In the operation of mutual monitoring of a duplex system,
The active side notifies the standby side of the change of the program or definition data, and if there is a change, the standby side copies the entire data area of the active side from itself, so the work of changing the program or definition data can be done. When performing this, it is only necessary to perform this change work on the operating side, and the change work can be performed without being aware of the duplication.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram as an embodiment of the present invention.

FIG. 2 is a flowchart showing a main part of a process at the time of turning on or resetting the control device.

FIG. 3 is a flowchart showing a transmission procedure of mutual monitoring between redundant controllers and a procedure of an operation right transfer confirmation operation of a standby controller;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Working-side program controller (working PC) 2 Standby-side program controller (standby PC) 2A Working-side all data copying means 3 Transmission path 4 Management personal computer 5 Loader 6 Equalization transmission path 7 I / O device 8 Control target

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 11/16-11/20 G06F 15/16-15/177

Claims (1)

(57) [Claims] 1. A control device comprising: a standby control device; and an active control device in which a program and fixed data are stored in advance. The active control device always controls a control target, and the standby control device operates at a predetermined cycle. In addition to monitoring the presence or absence of an abnormality in the control unit, the variable data is transferred from the control unit to itself, and in the event of a failure in the control unit, the standby control unit controls the control target in place of the control unit. The standby-side control device transfers the entire data including the program from the active-side control device to itself when the power is turned on and resets, and performs the monitoring of the active-side control device. Also, it checks whether there is any change in the program or fixed data of the operating control device, and when this change occurs, the operating control device sends all data including the program to itself. Equalization method of duplicated control system being characterized in that so as to transfer.