JPH1189073A - Setting change method of digital relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To completely avoid the intervention by a third party in the setting change of a digital (protective) relay using a public line. SOLUTION: A setting change method of a digital relay is such that the digital relay and a remote maintenance computer are connected to each other with a public line, and setting information is transmitted from the computer to the digital relay for changing the set value, etc., of the digital relay. At that time, a call-back function (103-106) is provided on the digital relay side and, when the set information is supplied from the public line (101 and 102), the connection is opened temporarily (103) and the digital relay is connected to a preset specific remote maintenance computer for executing a communication process (107) for the setting change in accordance with the call-back. As the communication process of the setting change of the digital relay is executed in accordance with the call-back, even if a third party attempts to falsify the setting through the public line, the setting change cannot be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital protection relay device (digital relay) for protecting a power system, which is used to change setting value information and setting information for maintenance and operation using a general communication line. The present invention relates to a method for changing the set value of a digital relay that can be safely operated from the beginning.

[0002]

2. Description of the Related Art When a large amount of information held by a digital relay (digital protection relay) at a substation or the like is monitored, operated, and maintained at a remote control station or the like, an information line is used at high speed to reduce communication costs. Cheap public telephone lines, ISDN lines,
It is conceivable to use an information line generally used as a communication means, such as a private LAN line. (Less than,
In addition to these control operators and digital relays,
A communication line to which a third party can connect is called a general line, and a communication line to which a third party cannot connect is called a dedicated line. In this case, as shown in FIG. 1, information such as a state detected by the digital relay 1, an operation state, and an abnormal state is collected by a remote maintenance computer 2 provided in a control center or the like, and the general line 3 is collected. Will be used for maintenance.

[0003]

There are various methods for protecting information on the current communication line, such as password processing and information encryption. However, besides the maintenance operator of the control station and the digital relay, On a general line that is also connected to a third party, a digital relay may be accessed.

In this case, it is not preferable that information such as a state detected by the current digital relay, an operating state, and an abnormal state is leaked to a third party. Changing the information on the protection performance, for example, may significantly reduce the protection performance of the digital relay.

[0005] However, in a current general line in which there is a possibility of connection from a third party, connection of the line to the digital relay must be said to be easy as follows.

A public telephone line using a modem or the like, IS
In the case of a DN line, if a telephone number is known, a digital relay can be accessed via a modem. Campus LA
N and the like are protocols used, for example, TCP / I
In the case of P, if the IP address is known, it can be connected to the digital relay.

As a result, the communication between the control center and the digital relay is monitored, and if the information exchange procedure at the application level can be decoded, the information of the digital relay can be obtained, or as if a third party is accessing from the control center. It is possible to change the setting of the digital relay during the operation.

[0008] The present invention has been made in view of the above-mentioned problems when the general line is used, and an object of the present invention is to prevent a third party from performing falsification work such as setting change, etc. It is an object of the present invention to provide a digital relay settling value changing method which can easily detect if the data has been tampered with and can immediately correct it.

[0009]

According to the present invention, a digital relay and a remote maintenance computer are connected by a general line,
In the digital relay setting change method, in which the setting information is transmitted from the remote maintenance computer to the digital relay to change the setting value, setting value, etc. of the digital relay, a callback function is provided on the digital relay side, and the setting information is transmitted from the general line. If received, the connection is once cut off and communication connection processing is performed only from the digital relay to the preset specific remote maintenance computer so that the setting change cannot be performed by a third party.

[0010] Alternatively, a dedicated line is provided between the digital relay and the remote maintenance computer, and an operation start command is transmitted from the remote maintenance computer to the digital relay via the dedicated line, so that a third party can intervene in the setting change. I made it impossible.

A dedicated line is provided between the digital relay and the remote maintenance computer. When the digital relay receives setting information from a general line, the digital relay performs a setting change process, and connects the dedicated line to the remote maintenance computer. The fact that the remote operation access has been made is transmitted via a third party, and the falsification of the setting information by a third party can be detected.

When the remote maintenance computer is informed that the remote maintenance access has been made, the remote maintenance computer is connected to the digital relay via a general line, and the set value of the digital relay and the remote maintenance computer are connected. The setting information is compared with the setting information of the digital relay, and when they do not match, the setting change processing of the digital relay is performed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

First Embodiment (Method of Using Callback Function of Modem Using General Line) When a public telephone line of a general line or a modem or terminal adapter of an ISDN line is used, a callback function is added to these line terminal functions. Or, by providing the digital relay with a callback function, communication between the two parties can be ensured by communicating from the digital relay to the telephone number or IP address of the control station whose digital relay has been previously set to the digital relay. I do.

[0014] Incidentally, the callback is a method in which communication connection processing is performed only to a specific connection destination set in advance in the digital relay itself in response to a communication connection request from the outside without accepting a communication connection from an unspecified large number.

In the first embodiment, the digital relay shown in FIG.
In the information communication system of the digital relay connected to the general line 3 via the communication line 5, the digital relay is safely settled only by the processing of the digital relay.

The processing contents of the digital relay 1 in this case will be described with reference to the flow chart of FIG. After the digital relay receives the incoming call from the general line 3 (101), it is determined whether or not the communication access is normal (102). If the access is normal, the line is temporarily disconnected (103) and set again in advance. Call processing is performed to the remote maintenance computer 2 of the designated control center (104).

Then, the connection with the computer 2 is confirmed (106). If the line connection cannot be established under the conditions such as BUSY while talking, a call is retried after waiting for a predetermined time (1).
06,104). When connected as described above, information exchange, setting change, etc. are performed between the computer 2 and the digital relay 1 according to the normal communication processing (107).

According to the first embodiment, when an incoming call is received, normal access is confirmed and the digital relay 1 calls the computer 2 to perform communication processing.
Is not falsified by a third party.

Embodiment 2 (Method Using General Line and Dedicated Line) In Embodiment 2, as shown in FIG. 1, a digital relay 1 provided in a substation and the like and a remote maintenance computer 2 of a control station are used. In a system in which information communication is performed via a general line 3 between a general line and a dedicated line such as a telecon line where no third party can enter, the “operation start” indicating the completion of the setting change operation is performed. This is a method for issuing a final command.

FIG. 3 shows the configuration of a digital relay maintenance and operation system according to the second embodiment. 1, reference numerals 1 to 5 denote an information communication system of a digital relay using a general line configured in the same manner as in FIG.
Is a teleconverter connected to the digital relay 1 side of the dedicated line 6, 8 is a teleconverter connected between the computer 2 and the dedicated line, 9 is a contact circuit from the teleconverter 7 to the digital relay 1, Only the "operation start command" for instructing the completion of the setting change process communicated via the dedicated line 6 and the tele-con 7 is transmitted as a one-position control signal, and the "operation start" command via the tele-con is input via the DI of the digital relay 1. The operation start process is performed by the above. Reference numeral 10 denotes a switch on the front side of the "operation start" device of the digital relay 1. Digital relay 1
Operate according to the flow of FIG.

The processing of the digital relay 1 will be described with reference to FIG. When the digital relay 1 receives a setting change command from the general line 3 (201Y) and enters the setting change processing (202), it monitors the timeout of the timer (203), and within a certain period of time until the timeout, the computer 2 sends the telecon (6 to 6). 8) When there is an operation start command via the terminal or a DI input of the operation start switch 10 on the front of the apparatus (20)
4Y), the operation start processing (205) is performed.

According to the second embodiment, even if there is a setting change command or the like from a general line, if the operation start command cannot be input to DI within a certain time, the setting change process is canceled. Is not done. Therefore, no alteration such as setting change is performed by a third party.

Embodiment 3 (Constant Monitoring System for Remote Operation Access Right)
A system that constantly monitors via a teleconverter, etc., a remote control station that should have remote operation access.Digital relay communication uses only general lines, communication connection processing,
The monitoring of important information is updated without taking any special measures.

FIG. 5 shows the configuration of a digital relay maintenance and operation system according to the third embodiment. In the drawing, reference numerals 1 to 5 denote an information communication system of a digital relay using a general line configured in the same manner as in FIG.
7 and 8 are teleconverters; 11 is a contact circuit for outputting a contact signal 11-1 from the digital relay 1 indicating that there is a "setting change from remote" to the telecon; 12 is a "setting change from remote" signal from the teleconverter 8; Reference numeral 13 denotes a contact circuit for inputting the signal 12 from the teleconverter 8 to the computer 2.

The processing contents of the digital relay 1 will be described with reference to the flow of FIG. The digital relay 1 performs various kinds of communication processing in response to the incoming call (301) of the general line 3, and determines whether or not the setting is changed (302). If the setting is changed, the setting is changed (303) and the operation is started. It is determined whether there is a command (304).

If there is an operation start command, the operation start processing (30
Under the condition 5), the alarm process (306) is performed, and the digital relay 1 performs the setting change process on the operation method of the computer 2 of the control center via the contact circuit 11 through the dedicated line 6 for the tele-con. Notify. At this time, the digital relay 1 outputs an alarm from the contact circuit 11 to the computer 2 via the dedicated line 6 on condition that the setting change is completed by the general line 3 from the incoming call.

It should be noted that the contact circuit 11 can use the alarm contact circuit that the digital relay 1 has conventionally.

According to the third embodiment, tampering of important information can be detected by monitoring the access status of a third party from a general line.

Embodiment 4 (Method of Comparing and Monitoring Update of Important Information (Set Value, Set Value)) Embodiment 4 is a computer for remote maintenance such as a control center or the like for important information such as set values, When setting values and the like are managed and remote operation access is detected as in the third embodiment, the remote maintenance computer sends a digital protection relay device to the digital protection relay device.
A communication connection is made again for confirmation, the set value and setting value managed by the remote maintenance computer are compared and checked by monitoring, and if there is a mismatch, it is corrected. .

The configuration of the digital relay maintenance operation system shown in FIG. 5 is used, and is realized by processing of a remote maintenance computer at the control center.

The processing of the remote maintenance computer will be described with reference to the operation flow of FIG. When the setting change alarm according to the third embodiment enters the remote maintenance computer 4 (40).
1) It is determined whether or not it is based on the setting change process performed by the computer 4 (402). If the determination result is N, the alarm output is released (403). If the determination result is Y, the digital relay 1 is reset. Make a call using a general line (40
4) Connect and perform set value read processing (40)
5) The readout result is set information stored in the remote maintenance computer 1, and it is determined whether or not there is a discrepancy in the settling value or not (406). If not, the setting change process is immediately performed. (407) Then, a means for returning to the original set value is prepared. Finally, the operation is started again with the original set value, and the general line is disconnected (408).

According to the fourth embodiment, tampering can be detected and corrected.

[0033]

【The invention's effect】

(1) According to the first aspect of the present invention, since the system has a callback function, it can be connected only to a remote maintenance computer such as a control station set in advance in a digital relay. With the use of a digital relay, it is possible to change the setting of the digital relay with high reliability without the intervention of a third party.

(2) According to the first aspect, in addition to performing a large amount of information communication of the digital relay through the general circuit, a final instruction of operation start indicating the completion of the setting change operation is exclusively used by a third party. Since the data is transmitted from the remote maintenance computer to the digital relay using the line, no third party can intervene, and the reliability is improved.

(3) According to the third aspect, it is possible to detect tampering of important information by monitoring the access state of a third party from a general line.

(4) According to the fourth aspect of the invention, the falsification is detected, and then the remote maintenance computer makes a communication connection to the digital relay again for confirmation and performs a comparison check, and corrects any inconsistency. Corrections can be made easily.

[Brief description of the drawings]

FIG. 1 is an information communication system configuration diagram of a digital relay according to a first embodiment.

FIG. 2 is a flowchart of a callback communication connection process of a digital relay.

FIG. 3 is a configuration diagram of a digital relay maintenance and operation system according to a second embodiment;

FIG. 4 is a processing flowchart when the digital relay is settled.

FIG. 5 is a configuration diagram of a digital relay maintenance and operation system according to a third embodiment;

FIG. 6 is a processing flow chart when setting change of a digital relay is performed.

FIG. 7 is a processing flow chart when the remote maintenance computer according to the fourth embodiment receives an alarm.

[Explanation of symbols]

1. Digital relay (digital protection relay) 2. Remote maintenance computer 3. General line (public telephone line, ISDN line, campus LA)
N, WAN, etc. 4, 5 Modem (or terminal adapter, LAN adapter, etc.) 6 Telephone dedicated line 7, 8 Telecom (distant vision control device) 9 Contact circuit 9-1 "Operation start" teleconverter Via contact signal 10 ... "Operation start" switch on the front of the device 11 ... Contact circuit 11-1 ... Contact signal with "setting change from remote" contact signal 12 ... Signal with "setting change from remote" via teleconverter 13 ... Contact circuit.

Claims (4)

[Claims] A digital relay and a remote maintenance computer are connected by a general line, and setting information of the digital relay is changed by transmitting setting information from the remote maintenance computer to the digital relay to change the digital relay setting value, setting value, and the like. In the system, the callback function is provided on the digital relay side, and when the setting information is received from the general line, the connection is temporarily disconnected, the communication connection processing is performed only from the digital relay to the specified remote maintenance computer, and the setting is changed. A setting change method of a digital relay, wherein a third party's intervention is not possible. 2. A digital relay setting change, wherein a digital relay and a remote maintenance computer are connected via a general line, and setting information is transmitted from the remote maintenance computer to the digital relay to change the digital relay setting value, setting value, and the like. In the system, a dedicated line is provided between the digital relay and the remote maintenance computer, an operation start command is transmitted from the remote maintenance computer to the digital relay via the dedicated line, and a setting change may be possible by a third party. A digital relay setting change method characterized in that it is not used. 3. A digital relay and a remote maintenance computer are connected by a general line, and setting information of the digital relay is changed by transmitting setting information from the remote maintenance computer to the digital relay to change the digital relay's set value, set value, and the like. In the system, between the digital relay and the remote maintenance computer,
When a dedicated line is provided and the digital relay receives the setting information from the general line, the digital relay performs a setting change process and informs the remote maintenance computer that the remote operation access has been made via the dedicated line. A setting change method for a digital relay, characterized in that tampering of setting information by the user can be detected. 4. The remote maintenance computer according to claim 3, wherein when the remote maintenance computer is notified that the remote maintenance access has been made, the remote maintenance computer is connected to the digital relay via a general line, and the digital relay setting value is set. And setting information of a remote maintenance computer is compared, and if they do not match, a digital relay setting change process is performed.