JP2013150435A - Protection relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protection relay capable of supporting various types of power stations by relieving a design change.SOLUTION: A basic unit 101 of the protection relay includes: a base section 110, and a first input conversion circuit section 111 and a second input conversion circuit section 112 each of which is installed on the base section to be detachable. In the first input conversion circuit section 111, a plurality of predetermined protection circuit functions are provided to previously meet connection terminals. In the second input conversion circuit section 112 as well, a plurality of predetermined protection circuit functions are provided to previously meet connection terminals.

Description

  The present invention relates to a protective relay device.

  Many protective relays are used to protect various circuits installed in an electric circuit to be protected, such as a power plant, connected to an electric power system. The main circuit as a protection target connected to the power system has a different configuration for each power plant.

  Therefore, a conventional protection relay device for protecting a power plant or a transformer is configured as a so-called device-type digital protection relay device so that it can be applied to the main circuit of all power plants (Patent Literature). 1).

  Conventional device-type digital protection relay device applies CPU (Central Processing Unit) board type and number, computer program, input and output points, VCT (Voltage and Current Transformer) input converter structure, etc. Each power plant has a design change every time.

  A protective relay device is also known in which hardware is divided into functions and can be detachably attached to a motherboard (Patent Document 2).

JP 2011-36059 A JP 2009-193105 A

  Since the configuration of the main circuit to be protected by the protective relay device is greatly different for each power plant, there are various types of protection circuits (protection elements). Therefore, in the device-type protective relay device in the prior art, the hardware configuration, the computer program, the sequencer program, and the like have to be greatly changed for each applied power plant.

  In the prior art of Patent Document 2, the hardware is divided for each function. However, since the combinations of types of input converters are enormous, it is difficult to limit the types of input converters. The conventional technology cannot deal with a wide range of electrical circuits to be protected with a small number of modules.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a protective relay device that can be applied to the protection of a wider range of electrical circuits and can reduce the effort of design changes.

  In order to solve the above problems, a protective relay device according to the present invention is a protective relay device for protecting a predetermined electric circuit connected to an electric power system, and has a plurality of protective circuit functions. The plurality of protection circuit functions are associated in advance with a plurality of connection terminals for connecting directly or indirectly to the power system.

  The predetermined electric circuit is an electric circuit to be protected by the protective relay device, and can include, for example, a main circuit of a power plant. The protection circuit function is a function of a protection circuit for protecting a predetermined electric circuit, and examples thereof include a differential current relay function and a field loss relay function. Directly or indirectly connected to the power system means not only when the current value or voltage value is measured by connecting directly to the power system, but also other circuits (protection circuit, other protective relay devices). This also includes the case where the current value or the voltage value is measured via.

  The protective relay device includes a base portion, a control portion that is detachably provided on the base portion, an input portion that is detachably provided on the base portion, and a digital input / output portion that is detachably provided on the base portion. You may comprise as a unit type protective relay apparatus. The plurality of protection circuit functions are associated in advance with the plurality of connection terminals of the input unit, and the protection circuit function corresponding to the connection terminal used among the plurality of connection terminals among the plurality of protection circuit functions. Operate.

  The input unit includes a first input unit and a second input unit, and a plurality of first protection circuit functions are associated with a plurality of first connection terminals of the first input unit in advance. A plurality of second protection circuit functions are associated with a plurality of second connection terminals of the second input unit in advance, and the plurality of first protection circuit functions are applicable to a predetermined electric circuit. Is selected from among a wide range of protection circuit functions, and a plurality of second protection circuit functions are selected from a plurality of protection circuit functions whose application range to a predetermined electrical circuit is narrower than the plurality of first protection circuit functions It may be configured to be.

  According to the present invention, a predetermined electric circuit can be protected with a relatively simple configuration.

1 is an overall schematic diagram of a protective relay device. The schematic block diagram of a basic unit. The schematic block diagram of an attached unit. The circuit diagram which shows the main circuit of a generator. Functional configuration diagram of a standard module. Functional configuration diagram of the semi-standard module. The functional block diagram of another semi-standard module. The functional block diagram of another semi-standard module. Functional configuration diagram of special module.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, as will be described in detail below, design changes for applying the protective relay device for each power plant can be suppressed to a small extent. The present embodiment can be applied to various thermal power generation main circuits such as so-called tandem, cross, and combined. The protective relay device of this embodiment can be applied to both a direct grounding generator and a resistance grounding generator. Furthermore, the protection relay device of the present embodiment can be applied to either a thyristor activation method or a half-speed two-axis synchronization method as a generator activation method.

  However, the description of the embodiment shows the configuration of the present invention within the scope necessary for understanding and implementation of the present invention, and the scope of the present invention is not limited to the configuration of the embodiment.

  FIG. 1 shows a schematic configuration of a control panel 100 that houses a protection circuit of a generator. The control panel 100 can accommodate a plurality of protective relay devices 101 (1), 101 (2), and 102 and can be electrically connected to the power system.

  The protective relay devices 101 (1) and 101 (2) are basic unit protective relay devices. Hereinafter, it is abbreviated as the basic unit 101. The basic unit 101 is configured based on knowledge obtained by analyzing circuit diagrams of a plurality of (many) main circuits. The basic unit 101 incorporates a frequently used protection circuit function so that it can be used to protect as many main circuits as possible. The basic unit 101 includes, for example, a base unit 110, a first input conversion circuit unit 111, a second input conversion circuit unit 112, an output circuit unit 113, and a control unit 114.

  The protective relay device 102 of the attached unit is used when the basic unit 101 alone cannot cope. Hereinafter, it is abbreviated as the accessory unit 102. As with the basic unit 101, the attached unit 102 includes a base unit 110, a first input conversion circuit 111, and an output circuit 113, but does not include the second input conversion circuit unit 112.

  The base part 110 is for detachably attaching the circuit parts 111, 112, 113, and 114, and has a connector and a bus (not shown) for electrically connecting the circuit parts 111 to 114. I have.

  Input signals (current signal, voltage signal, frequency signal) detected by the power system are input to the input conversion circuit units 111 and 112. A configuration example of each of the input conversion circuit units 111 and 112 will be described later.

  The digital input / output unit 113 outputs a signal to a circuit breaker or other protective relay device, for example. The control unit 114 performs arithmetic processing based on various signals input to the input conversion circuit units 111 and 112, and outputs a calculation result from the digital input / output unit 113.

  A configuration example of the basic unit 101 will be described with reference to FIG. As described above, the basic unit 101 includes the plurality of input conversion circuit units 111 and 112. One standard module M1 prepared in advance is attached to the first input conversion circuit unit 111. The standard module M1 includes a plurality of basic protection circuit functions (also called essential protection circuit functions) used in almost all power plants. The protection circuit function of the standard module M1 will be described later with reference to FIG.

  One of the plurality of semi-standard modules M2, M3, and M4 prepared in advance is selected and attached to the second input conversion circuit unit 112. The semi-standard modules M2 to M4 each include a plurality of other protection circuit functions in accordance with the basic protection circuit function included in the standard module M1.

  In order to distinguish the protection circuit function built in the semi-standard modules M2 to M4 from the basic protection circuit function, they are referred to herein as auxiliary protection circuit functions. Each of the semi-standard modules M2 to M4 has a plurality of different auxiliary protection circuit functions.

  Therefore, the combination of the basic unit 101 includes a total of three types including the standard module M1 and the first semi-standard module M2, the standard module M1 and the second semi-standard module M3, and the standard module M1 and the third semi-standard module M4. Become. By adding one attachment unit 102 to the three types of combinations of the basic unit 101, four types of patterns can be obtained as a whole.

  As described above, the basic unit 101 of this embodiment includes one standard module M1 and any one semi-standard module selected from the semi-standard modules M2 to M4 according to the configuration of the main circuit and the like. .

  In the present embodiment, three semi-standard modules M2 to M4 are illustrated, but a configuration in which two or more semi-standard modules are selected from two or four or more semi-standard modules may be used. A plurality of digital input / output units 113 may be provided, or a circuit unit other than the illustrated circuit units 111 to 114 may be attached to the base unit 110.

  FIG. 3 shows a configuration example of the attached unit 102. The attachment unit 102 has the same mechanical and electrical structure as the basic unit 101. However, in the attached unit 102, one of the special modules M10 and M11 prepared in advance is selected and attached to the first input conversion circuit unit 111. For example, a dust prevention cover or the like can be attached to the second input conversion circuit unit 112 of the attached unit 102, but no circuit unit module is mounted. The accessory unit 102 is exceptionally partially used when the basic unit 101 alone cannot cope.

  FIG. 4 shows a main circuit for protecting the generator. FIG. 4 is a diagram in which necessary elements are extracted from a single-line diagram of a plurality of main circuits and summarized on one single-line diagram. In FIG. 4, protection elements that can be widely applied are extracted from various protection elements (protection circuit functions) and displayed.

  A three-phase AC power source (generator) 1 installed in a power plant such as a thermal power plant or a hydro power plant is connected to a bus 40 via a transformer step-up transformer 4 and a circuit breaker 30. A plurality of CTs (instrument current transformers) and VTs (instrument transformers) are installed in the middle of the line connecting the three-phase AC power supply 1 and the bus 40. Each CT is connected to a digital protection relay device (also called a protection relay).

  In FIG. 4, reference numeral 3 is an exciter transformer, reference numeral 5 is a ratio differential relay (87G), reference numeral 6 is a reverse phase overcurrent relay (46G), reference numeral 7 is a field ground fault relay (40G), and reference numeral 8 is a distance. Relay (44G), reference numeral 9 is a reverse power relay (67G), reference numeral 10 is an overvoltage relay (51G), reference numeral 11 is a voltage balancing relay (60G), reference numeral 12 is an overexcitation protection relay (59V /), and reference numeral 13 is a frequency. Relay (95GH), reference numeral 14 is a frequency relay (95GL), reference numeral 15 is an overvoltage relay (59G), and reference numeral 16 is an overcurrent protection relay (50P) at start-up.

  Further, reference numeral 21 is a ground fault ratio differential relay (87GG), reference numeral 22 is a ground fault overvoltage relay (64PG), reference numeral 23 is a ground fault overvoltage relay (64G), and reference numeral 24 is an overcurrent protection relay at start-up. (50P), 25 is a ground fault protection relay (51NG), 26 and 27 are ground fault overcurrent protection relays (51GNG), and 28 is an overcurrent protection relay (50P) at startup. Reference numeral 50 denotes a ground resistance.

  Since the various protection elements 6 to 16 and 21 to 28 shown in FIG. 4 are provided, it can be applied to all so-called tandem, cross and combined thermal power generation main circuits. In particular, for example, since each of the elements 64G, 64PG, 87GG, 51NG, and 51GNG is included, the generator can cope with either a direct grounding system or a resistance grounding system. Further, by including the element 50P, it is possible to cope with any of the thyristor starting method and the half speed two-axis synchronous method as the generator starting method.

  FIG. 5 shows a functional configuration example of the standard module M1 attached to the first input conversion circuit unit 111 of the basic unit 101. The standard module M1 includes, for example, nine input terminals (connection terminals). In this embodiment, each module can input 9 points of signals.

  A rated current or a rated voltage is set for each terminal. Among the various protection circuit functions such as 87G described above, a predetermined protection circuit function is associated with each terminal of each module in advance. For example, in the case of the standard module M1 shown in FIG. 5, the six terminals of terminal numbers 1 to 6 are connected to the input of the ground fault ratio differential relay 87G (three points (# 1 to # 3) on the main transformer side). And 3 points (# 4 to # 6) on the neutral point side.

  The other three terminals (# 7 to # 9) are assigned to the elements 46G, 40G, 44G, 67G, 51G, 57G, 56, and 67 described above. By connecting signal lines to the terminals # 7 to # 9, among the standard module M1, the circuits corresponding to the terminals # 7 to # 9 are elements 46G, 40G, 44G, 67G, 51G, 57G, 56, 67. Act as one of them.

  The standard module M1 attached to the first input conversion circuit unit 111 of the basic unit 101 has only a basic protection circuit function (essential protection circuit function) that is always used in the protection circuits of all generators. . In addition, as shown as the standard module M1A on the lower side of FIG. 5, the association between the terminal number and the basic protection circuit function can be changed.

  6 to 8 show functional configuration examples of the semi-standard modules M2 to M4 attached to the second input conversion circuit unit 112 of the basic unit 101. FIG. The semi-standard modules M2 to M4 have built-in auxiliary protection circuit functions that are used differently for each power plant. The semi-standard modules M2 to M4 also have nine terminals, and each terminal is associated with an auxiliary protection circuit function in advance.

  Examples of the auxiliary protection circuit function include 60G, 59V / F, 95GH, 95GL, 59G, 40G, 44G, 60G, 87GG, 87GG, 51NG, 51GNG, and 64PG.

  Most main circuits can be handled only by the basic unit 101, which is a combination of the standard module M1 and any one of the semi-standard modules M2 to M4, but there is also a special main circuit that cannot be adapted only by the basic unit 106. obtain. Therefore, in this embodiment, such a special main circuit is handled by a specially prepared accessory unit 102.

  FIG. 9 is an example of the special module M10 attached to the attached unit 102. A special protection circuit function is associated with the terminal of the special module M10. As a special protection circuit function, for example, element 50P (rated 1A, corresponding to low frequency input of 10 to 50 Hz), element 50P (corresponding to rated 5A, low frequency input of 10 to 50 Hz), element 51GNG (rated 5A, Used outside of CT).

  In the present embodiment, as described above, the basic unit 101 is configured by analyzing a single-line diagram of a plurality of main circuits and extracting a predetermined protection circuit function that can be widely applied from various protection circuit functions. did. Therefore, the configuration pattern of the basic unit 101 can be limited to four patterns, and the design cost of the protective relay device can be reduced.

  In this embodiment, only one of the standard module M1 and the semi-standard modules M2 to M4 is mounted on the basic unit 101, and only a desired protection circuit function is obtained by connecting a signal line to a predetermined terminal. You can select and use. Therefore, it is possible to cope with various power plants with few design changes.

  In this embodiment, only the interlock logic circuit and the trip output circuit (OR or NAND), which require a design change for each power plant adaptation, can be configured to be customized.

  Furthermore, in this embodiment, since a plurality of types of protection circuit functions are built in each of the modules M1, M2 to M4, M10, a smaller number of protection relay devices 101 and 102 can be used for various power plants. Can do.

  In addition, this invention is not limited to the Example mentioned above. A person skilled in the art can make various additions and changes within the scope of the present invention.

  101: basic unit, 102: accessory unit, 111: first input conversion circuit unit, 112: second input conversion circuit unit, M1: standard module, M2, M3, M4: semi-standard module, M10, M11: special module

Claims (6)

A protective relay device for protecting a predetermined electric circuit connected to an electric power system,
Built-in multiple protection circuit functions
The plurality of protection circuit functions are associated in advance with a plurality of connection terminals for connecting directly or indirectly to the power system.
Protective relay device. A base part;
A control unit detachably provided on the base unit;
An input part detachably provided on the base part;
A digital input / output unit detachably provided on the base unit;
With
The plurality of protection circuit functions are associated in advance with a plurality of connection terminals of the input unit,
Among the plurality of protection circuit functions, a protection circuit function corresponding to a connection terminal used among the plurality of connection terminals is activated.
The protective relay device according to claim 1. The input unit includes a first input unit and a second input unit,
A plurality of first protection circuit functions are associated with a plurality of first connection terminals of the first input unit in advance,
A plurality of second protection circuit functions are associated with a plurality of second connection terminals of the second input unit in advance,
The plurality of first protection circuit functions are selected from protection circuit functions having a wide range of application to the predetermined electrical circuit,
The plurality of second protection circuit functions are selected from protection circuit functions whose application range to the predetermined electric circuit is narrower than the plurality of first protection circuit functions.
The protective relay device according to claim 2. From among a plurality of types of second input units prepared in advance, any one of the second input units to be attached to the base unit is selected.
The protective relay device according to claim 3. At least one of the correspondence relationship between the plurality of first connection terminals and the plurality of first protection circuit functions, or the correspondence relationship between the plurality of second connection terminals and the plurality of second protection circuit functions. The correspondence of can be changed,
The protective relay device according to claim 4. The plurality of first protection circuit functions include at least a differential current relay function and a field loss relay function.
The protective relay device according to claim 5.

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