JPH11262165A - Protective relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save the spaces of a programmable logic controller and a protective relay, by inserting a device into a mother board having a channel which permits data transmission between devices inserted into respective slots. SOLUTION: The substrate of a protective relay 5 is mounted directly on a programmable logic controller(PLC) chassis slot, and the PLC4 and protective relay 5 share a mother board. The PLC4 and protective relay 5 are closely connected with each other by a channel 6 on the mother board, thus it is possible to save spacing and wiring when they are stored in a distribution panel or a control panel, thereby conducting efficient and high-speed communication between them. The PLC4 samples a current value from a current transformer CT through the protective relay 5 without through an analog input substrate. The protective relay 5 samples the current value at high frequency of a few millimeters from the current transformer CT, thus it is possible to obtain the current value at the same sampling frequency in PLC4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective relay device for protecting a system by interrupting an electric circuit with a circuit breaker in an accident.

[0002]

2. Description of the Related Art In the event of an accident or the like, a protective relay device for protecting a power system by interrupting the system with a circuit breaker is widely used. FIG. 6 is a diagram illustrating an example of a conventional protection relay device.

[0003] This protection relay device is configured such that a collective PLC chassis 54 of a programmable logic controller (hereinafter referred to as PLC) and a plurality of protection relays 52 are provided on a switchboard or control panel 51. Also, a hard wire (not shown) is provided between the collective PLC chassis 54 and the protection relay 52 to perform data transmission between them.

FIG. 7 is a diagram showing the relationship among a collective PLC chassis in which a PLC is provided, a relay, and a power system. The power system includes a current transformer CT that measures the current of the system,
A circuit breaker CB is provided. On the other hand, the collective PLC chassis 54 includes a PLC 53, a digital input board 55, a digital output board 56, and an analog input board 57. Note that a motherboard is provided in the collective PLC chassis 54. The PLC 53, the digital input board 55, the digital output board 56, and the analog input board 57
Is a card or board inserted into the motherboard, which is electrically connected directly with the data communication path of the motherboard.

[0005] The analog current value measured by the current transformer CT is input to an analog input board 57, where it is A / D converted and converted into a PLC 5 via a data communication path of a motherboard.
3 is transmitted. The PLC 53 that has received the current value executes a predetermined process such as notifying the above-mentioned computer. For example, when a command to shut off the circuit breaker CT comes from a host computer, the PLC 53 sends the command to the digital output board 6.
And the corresponding circuit breaker CT is cut off.

On the other hand, the protection relay 52 is intended to shut off the circuit breaker CB when an abnormality occurs in the electric power system. Although not shown in FIG. 7, the protection relay 52 constantly monitors the measured current value of the current transformer CT. doing. When an abnormality is detected from the current value, the circuit breaker CB is immediately shut off. In addition, a result of the interruption is reported to the PLC 53 via the digital input board 7.

[0007]

However, when the configuration shown in FIG. 6 is adopted, the collective PLC chassis 5
4 and the protection relay 52 separately from the switchboard or control panel 5.
In order to mount the device on a large space, a large space is required. In addition, since wiring is performed between the collective PLC chassis 54 and each protection relay 52 by hard wiring, the wiring becomes complicated and complicated. Further, if the number of input / output points increases, the number of input / output boards increases, and maintenance is not easy.

Further, in the conventional protective relay device, the measured current from the current transformer CT is sampled by the analog input board 7 at a cycle of about 200 milliseconds and input to the PLC 53. However, the operation of the protection relay 53 is performed based on current monitoring of about several milliseconds, and when the relay is cut off, the measured current may not be obtained at necessary intervals in the PLC 53 in some cases. Therefore, from the viewpoint of enhancing driving support by the PLC 53, the conventional protective relay device was insufficient.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and a first object of the present invention is to reduce the space required for mounting the PLC and the protective relay, and to reduce the space between the PLC, the protective relay and each of the external devices. It is an object of the present invention to provide a protective relay device that can reduce the number of wires. A second object is to provide a protection relay device that can easily add a driving operation support function to a PLC.

[0010]

According to a first aspect of the present invention, there is provided a communication path comprising a plurality of slots and realizing data transmission between devices inserted in each slot. This is realized by inserting a device into a motherboard having the device.

First, at least one insertable slot
Two protective relays are provided. In addition, a programmable logic controller (PL
C) is provided, and this PLC communicates with the protection relay via a communication path. Since this communication is direct communication via a communication channel, it can be performed at high speed.

As described above, the protection relay and the PLC are inserted into one motherboard so that they can communicate with each other.
The space for mounting the PLC and the protection relay can be saved, and the wiring between the PLC and the protection relay and each of the outside can be reduced.

[0013] Also, by using the communication function for both,
A driving operation support function can be easily added to the PLC. Next, according to a second aspect of the present invention, one or more of the following functions are added to a programmable logic controller to perform driving operation support and the like. These functions utilize direct high-speed communication between the PLC and the protective relay.

First, a high-speed data sampling function for sampling at least data from the current transformer via the protection relay, and a protection for collectively loading the set values of the protection relay to all the protection relays via the communication path. Failure factor analysis function that outputs behavior information of each data to analyze failure factors at the time of failure based on data obtained by relay settling value batch loading function and high-speed data sampling function, and circuit breaker switching This is a circuit breaker switching / trip history function for acquiring and recording the number of times, time, and / or history at the time of a failure trip from the protection relay. As described above, in the present invention, the driving operation support function can be easily added to the PLC.

[0015]

Embodiments of the present invention will be described below. (First Embodiment of the Invention) FIG. 1 is a configuration diagram showing an example of a protective relay device according to a first embodiment of the present invention.

This protection relay device is constructed by mounting a collective PLC chassis 2 which is a frame of a protection relay device main body on a switchboard or control panel 1. FIG. 2 is a diagram showing a main configuration in a collective PLC chassis in the protection relay device of the present embodiment.

As shown in FIG. 1, the collective chassis 2 includes a motherboard 3 and a PL inserted into the motherboard 3.
Each board such as C4 and protection relay 5 (shown in FIG. 1) is inserted, and a protection cover (not shown) is further provided.

A digital data communication path 6 is provided on the motherboard 3 and forms a data bus between the boards. The motherboard 3 has a plurality of slots 7, into which the boards such as the PLC 4 and the protective relay 5 can be inserted. Figure 2 shows PLC4
Only the state where only the motherboard 3 is inserted is shown. Note that an analog input board, a digital input board, or a digital output board can be inserted into the motherboard 3 as in the related art.

On the other hand, substrates such as the PLC 4 and the protective relay 5 are configured to be insertable into the respective slots 7 of the motherboard 3 as shown in FIG. An insertion connector 8 as an electrical connection is provided.

FIG. 3 is a diagram showing an electrical connection relationship in the protection relay device of the present embodiment. In the protection relay device of the present embodiment, a plurality of protection relays 5 share a motherboard 3 and are connected to a PLC 4 via a data communication path 6.

The PLC 4 has a CPU and a communication function, executes various device operations and sequence control, and communicates tightly with the protection relay 5 via the communication path 6 of the motherboard 3. In addition, high-speed data exchange with the protection relay 5 is thereby performed. Further, PL
C4 is connected to a host computer (not shown) and exchanges information.

The protection relay 5 is a digital protection relay for performing digital processing, and is directly housed and mounted on the motherboard 3 of the collective PLC chassis 2 as described above. Also, contact signals and analog signals from the circuit breaker CB and the current transformer CT (instrument transformer) are input and output by hard wiring. That is, it has an original circuit breaker function of taking in the current value of the current transformer CT and tripping the circuit breaker CB according to the current value and the like. It also has a communication function,
The shutoff result of the breaker CB and the measured value of the current transformer can be delivered to the LC 4 via the data communication path 6 at a high speed, and has a function of shutting off the breaker CB in response to a shutoff command from the PLC 4.

Next, the operation of the protection relay device according to the embodiment of the present invention configured as described above will be described.
Since the board of the protection relay 5 of the present embodiment is directly mounted on the PLC chassis slot 7, the PLC 4 and the protection relay 5 share the motherboard 3. As a result, the PLC 4 and the protective relay 5 are tightly coupled in the communication path 6 on the motherboard, so that space and wiring can be reduced when the power supply is stored in the switchboard or the control panel 1, and efficient and high-speed communication between the two. Communication becomes possible. This is because there is no need to use a digital input board for signal transmission.

In response, the PLC 4 samples the current value from the current transformer CT via the protection relay 5 without passing through the analog input board. Since the protection relay 5 performs sampling at a high frequency of about several milliseconds from the current transformer CT, the PLC 4 can also obtain a current value at this sampling frequency. For this reason, a current transformer current value corresponding to the operation of the protection relay 5 is obtained.

FIG. 4 is a diagram showing a change in current value when the system is cut off by the protection relay. As shown in the figure, when an abnormality occurs in the system and the current value increases, a trip signal is output by the protection relay 5 and the circuit breaker CB operates. As a result, the current value decreases, and the power system is protected. Although not particularly shown, at this time, since the protection relay 5 samples the current value at a high frequency of about several milliseconds from the current transformer CT, a sufficiently appropriate cutoff operation is performed in response to a sudden current change. Will be.

On the other hand, when the current transformer current is measured via, for example, an analog input board, the sampling cycle is about 200 milliseconds, so that the sampling is not sufficiently performed in response to the breaking operation of the circuit breaker CT. . For this reason,
As shown in FIG. 4, the host computer receiving the measurement result may not be able to confirm how the current abnormality has been detected in the protection relay 5. However, in the present embodiment, since the current transformer current is delivered between the PLC 4 and the protection relay 5 that are tightly coupled via the communication path 3 on the motherboard, the PLC 4
The host computer that receives the measurement result from the above can obtain sufficient information for analysis and the like.

In the above case, the current transformer current has been described. However, between the PLC 4 and the protection relay 5 which are tightly coupled via the communication path 3 on the motherboard, in addition to the switching contact information of the circuit breaker, analog Information, failure information, parameter information inside the protection relay, set value information, and the like are also exchanged at high speed.

As described above, the protection relay device according to the embodiment of the present invention is configured such that the protection relay 5 can be inserted into the slot 7 on the motherboard 3 to share the motherboard, and that the protection relay 5 is more densely connected to the motherboard communication path 6. Combined P
Since various types of data transmission are performed between the LC 4 and the protection relay 5, the mounting space between the PLC and the protection relay is reduced, the wiring between the PLC, the protection relay, and each of the external devices is reduced. As a result of the coupling, data such as switching contact information of a circuit breaker, analog information, failure information, and parameter information and set value information inside a protection relay can be easily and quickly exchanged.

That is, in the present embodiment, data can be taken in without going through an interface or A / D conversion means on an analog input board or the like, so that high-speed and high-precision data sampling can be performed in the PLC. (Second Embodiment of the Invention) The protection relay device of the present embodiment is similar to the protection relay device of the first embodiment except that
PLC using high-speed data transfer function between protection relays
Various additional functions are added to.

FIG. 5 is a diagram showing functions added to the PLC of the protection relay device according to the second embodiment of the present invention.
1 to 3 are denoted by the same reference numerals and description thereof will be omitted, and only different portions will be described here.

This protection relay device has the same configuration as that of the first embodiment except that various functions are added to the PLC 4 '. The PLC 4 'has the following functional means in addition to the configuration similar to that of the first embodiment. These functions are PLC4 '
Function realizing means realized by combining hardware means such as a CPU and a memory with a program (software means) for controlling the hardware.

That is, the function of the PLC 4 'is to provide a high-speed data sampling function (1) for high-speed data sampling of contact signals and analog signals from each circuit breaker and current transformer (instrument transformer), and a communication path on the motherboard. Protection relay parameter batch management function (2) for collectively managing various set value parameters (set values, etc.) of the protection relay obtained through the relay, and setting values of each protection relay to the protection relay via a communication path on the motherboard. Protection relay set value batch loading function for batch loading (3), failure factors for analyzing failure factors from contact information and analog signal behavior information at the time of failure based on data obtained from the high-speed data sampling function Analysis function (4), automatic protection coordination to automatically generate overcurrent protection coordination and ground fault protection coordination for each protection relay No. (5), a circuit breaker switching / trip history function (6) that records the number of times and time of circuit breaker switching and time, and a history of a fault trip, and an operation sequence function (7) that has a circuit breaker control and sequence function is there.

Each function of the PLC 4 'is provided by a man-machine
To interface, a personal computer 9 (hereinafter, a personal computer 9) is used as a host computer by the PLC 4 '.
It is connected to the.

In the protection relay device of the present embodiment configured as described above, in addition to the PLC inherent sequence control, high-speed data sampling, protection relay parameter batch management,
Batch loading of protection relay set values, failure factor analysis, automatic protection coordination, circuit breaker switching / trip history, etc. can be easily performed.

Each of these functions is performed by the motherboard communication path 6.
This is realized by various data transmissions between the PLC 4 and the protection relay 5 which are more tightly coupled. For example, the failure factor analysis function (4) facilitates analysis at the time of occurrence of an accident because data sampling can be performed at a high cycle.
In addition, the protection relay parameter batch management function (2) and the protection relay set value batch loading function (3) are provided by the PLC.
This is a function that can be realized because the 4 'and the protection relay 5 are tightly coupled by the data communication path 6. The automatic protection coordination creation function (5) is a function for adjusting the coordination operation between the plurality of protection relays 5, and also in a case where all the protection relays 5 are connected to the PLC 4 'by one communication path 6. It is realized from.

As described above, the protection relay device according to the embodiment of the present invention has various functions mounted on the PLC 4 ′, and the PLC 4 ′ is tightly coupled with the motherboard communication path 6.
Since these functions are realized by using high-speed data transmission between C4 and the protection relay 5, it is possible to add high functions for the purpose of driving operation support to the PLC 4 'by PLC programming. Therefore, the protection relay side can concentrate on the protection function only, while the PLC
By increasing the measurement function on the side, a high-performance system as a whole can be achieved.

That is, in addition to the sequence operation conventionally performed in the PLC, high-speed data sampling, batch control of protection relay parameters, batch loading of protection relay set values, failure factor analysis, automatic protection coordination creation, circuit breaker switching / tripping History and the like can be easily performed. Thus, it is possible to contribute to the driving operation support of the operator.

The present invention is not limited to the above embodiments, but can be variously modified without departing from the scope of the invention. The method described in the embodiment may be a program (software means) that can be executed by a computer (computer), for example, a magnetic disk (floppy disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), semiconductor It can also be stored in a storage medium such as a memory or transmitted and distributed via a communication medium. The program stored on the medium side includes a setting program for causing the computer to execute software means (including not only an execution program but also a table and a data structure) to be executed in the computer. A computer that realizes the present apparatus reads a program recorded in a storage medium, and in some cases, constructs software means by using a setting program, and executes the above-described processing by controlling the operation of the software means.

[0039]

As described above in detail, according to the present invention, P
It is possible to provide a protection relay device capable of saving the space for mounting the LC and the protection relay and reducing the wiring between the PLC, the protection relay, and each of the outside. Further, according to the present invention, it is possible to provide a protective relay device that can easily add a driving operation support function to a PLC.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of a protection relay device according to a first embodiment of the present invention.

FIG. 2 is a collective PLC in the protection relay device of the embodiment.
The figure which shows the main components in a chassis.

FIG. 3 is an exemplary view showing an electrical connection relationship in the protection relay device of the embodiment.

FIG. 4 is a diagram showing a change in a current value when a system interruption is performed by a protection relay.

FIG. 5 is a diagram showing functions added to a PLC of a protection relay device according to a second embodiment of the present invention.

FIG. 6 is a diagram showing an example of a conventional protection relay device.

FIG. 7 is a diagram showing a relationship among a collective PLC chassis provided with a PLC, a relay, and a power system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Distribution board or control panel 2 ... Collective PLC chassis 3 ... Motherboard 4, 4 '... PLC 5 ... Protection relay 6 ... Data communication path 7 ... Slot 8 ... Connector 9 ... Personal computer CB ... Circuit breaker CT ... Current transformer

Claims (2)

[Claims] 1. A motherboard comprising a plurality of slots and having a communication path for realizing data transmission between devices inserted into each slot, at least one protective relay insertable into the slot, and inserted into the slot A protection relay device, comprising: a programmable logic controller capable of communicating with the protection relay via the communication path. 2. The programmable logic controller has a high-speed data sampling function of sampling at least data from a current transformer via the protection relay, and a set value of the protection relay to all protection relays via the communication path. Protection relay setting value batch loading function for batch loading, failure factor analysis function for outputting behavior information of each data to analyze failure factors at the time of failure based on data obtained by the high-speed data sampling function, circuit breaker 2. The circuit breaker according to claim 1, wherein at least one of the functions of a circuit breaker opening / closing / trip history function of acquiring and recording the history of the number of times of opening / closing, time, and / or failure trip from the protection relay is provided. Protection relay device.