KR20200100140A - Transformer protection relay device - Google Patents

Abstract

The transformer protection relay device of the embodiment has an acquisition unit and an operation unit. The calculation unit calculates a difference current between at least a phase current on the primary side of the transformer and a phase current on the secondary side of the transformer from the amount of electricity in accordance with the amount of power of the transformer acquired by the acquisition unit, to information on the predetermined winding configuration. It is calculated based on the operation status of the current differential relay of the transformer, and the operation status of the current differential relay is operated, and information on the operation status of the operated current differential relay, and the maximum difference current information on a phase in which the calculated difference current value exceeds a predetermined value. On the basis of, the operational phase in which the current differential relay reliably operates is extracted to calculate the operational quantity, and at least, the operational quantity and the phase in which the current value of each phase for each winding of the transformer exceeds a predetermined value. Based on the information on the maximum phase current related to the phase current and the information on the type of wiring of the winding, an accidental event of a system accident due to the transformer is determined.

Description

Transformer protection relay device

An embodiment of the present invention relates to a transformer protection relay device.

The transformer protection relay device detects an accident in the transformer by using a current differential relay for transformer protection. The current differential relay for transformer protection is, for example, according to the configuration of the windings on the primary and secondary sides of the transformer, for a set of the primary and secondary windings of the phase to be detected. The phase and magnitude of the phase current are matched, and the difference current Id of the phase is calculated. When an accident occurs on the object to be detected, the differential current Id is generated, and the transformer protection current differential relay detects the occurrence of the differential current Id and operates. There are cases in which sufficient information to determine an accident in which an accident occurred may not be obtained using only information on the phase (referred to as an operation phase) in which the current differential relay for protection of such a transformer was operated.

Japanese Unexamined Patent Publication No. 2002-186169

The problem to be solved by the present invention is to provide a transformer protection relay device capable of determining an accident in which an accident has occurred.

The transformer protection relay device of the embodiment has an acquisition unit and an operation unit. The acquisition unit acquires the amount of electricity according to the amount of electricity of the transformer having a winding configuration of a predetermined order. The calculation unit calculates a differential current between at least a phase current on the primary side of the transformer and a phase current on the secondary side of the transformer from the obtained amount of electricity, based on the information on the predetermined winding configuration, and the current differential relay of the transformer The current differential relay is reliably operated based on the operation status determination and operation information of the operated current differential relay and the difference current maximum phase information on the phase in which the calculated difference current value exceeds a predetermined value. The operational quantity is calculated by extracting the operational phase, and at least, the phase current maximum phase information about the phase in which the operational quantity and the current value of each phase for each winding of the transformer exceeds a predetermined value, and the wiring of the winding. ) Based on the information of the type, determine the accident of the system accident caused by the transformer.

1 is a diagram showing a configuration of a transformer protection relay device according to a first embodiment.
Fig. 2 is a diagram showing a configuration example of a transformer including a primary winding and a secondary winding of the embodiment.
Fig. 3 is a diagram showing a configuration example of a transformer including a primary winding and a secondary winding of the embodiment.
4 is a diagram showing an example of a configuration of an operation unit according to an embodiment.
Fig. 5 is a flow chart showing a procedure of determination processing according to the embodiment.
Fig. 6 is a diagram showing an example of a configuration of a determination unit on operation of a current differential relay according to an embodiment.
Fig. 7 is a flow chart showing a more specific procedure of a first step in the flow chart of Fig. 5;
Fig. 8 is a flow chart showing a more specific procedure of a second step S42 in the flow chart of Fig. 5;
9 is a diagram showing the configuration of a transformer protection relay system according to a second embodiment.
Fig. 10 is a diagram showing a configuration example of a transformer including a primary winding, a secondary winding, and a tertiary winding of the embodiment.
Fig. 11 is a flow chart showing a procedure of determination processing according to the embodiment.

Hereinafter, a transformer protection relay device according to an embodiment will be described with reference to the drawings. Further, in the following description, the same reference numerals are assigned to configurations having the same or similar functions. In addition, redundant explanations of their configurations may be omitted.

The transformer protection relay system according to the embodiment includes a transformer protection relay device. In addition, the "differential current" as used herein refers to an index showing the result of comparing the magnitude of the phase current of a specific phase on the primary side of the transformer with the magnitude of the phase current on the secondary side of the transformer corresponding to the phase. For example, the difference current is obtained by comparing the phase current based on the result of a predetermined matching operation based on the number of turns ratio and the phase difference from the phase current detected on the primary side and the secondary side of the transformer. In addition, "information on the operation of the current differential relay" refers to information indicating a phase (operational phase) in which the current-operated relay provided in the transformer responds due to an accident in the transformer or the like. In addition, "maximum difference current phase information" refers to information on a phase in which the value of the difference current takes a value equal to or greater than a predetermined value among the values of the difference currents of each phase of the transformer. The predetermined value may be determined based on the value of the phase difference current at which the difference current was the maximum. The calculation method will be described later.

(First embodiment)

1 is a diagram showing a configuration of a transformer protection relay system 1 according to an embodiment.

The transformer protection relay system 1 includes a transformer 2, a transformer protection relay device 3, current transformers 111 to 113, and current transformers 121 to 123.

The transformer 2 includes a primary winding and a secondary winding insulated from each other, and the specifications of the primary winding and the secondary winding are all three-phase AC specifications. Current transformers 111 to 113 are provided on a line on the primary side of the transformer 2, and current transformers 121 to 123 are provided on a line on the secondary side, respectively. Each current transformer generates at least a phase current flowing in a primary side line of the transformer 2 and a phase current flowing in a secondary side line from an amount of electricity corresponding to the amount of electric power of the transformer 2. The position on the track where each of the above current transformers is installed may be appropriately determined. In addition, instead of the current transformer, it is possible to detect the amount of electricity according to the amount of electricity of the transformer 2, and generate a phase current flowing through the line on the primary side of the transformer 2 at least and the phase current flowing through the line on the secondary side from the electricity amount. do.

Further, in the transformer 2 shown in Fig. 1, the connection of the primary winding is a neutral point grounded Y connection (star connection), and the connection of the secondary winding is a non-grounded Δ connection (delta connection). Such a configuration of the transformer 2 is referred to as "Yd1 configuration" (Fig. 2). In addition, the wiring of this transformer 2 shows an example, and is not limited to this.

The currents of each winding of the primary side of the transformer 2 are I1a', I1b', and I1c'. If the current flowing through the line connected to the primary side is matched to the phases a to c to be I1a, I1b, and I1c, the current flowing through each line and the current of each winding coincide. The current transformers 111 to 113 output current information i1a, i1b, i1c corresponding to these currents I1a, I1b, and I1c, respectively.

The currents of each winding of the secondary side of the transformer 2 are I2a', I2b' and I2c'. If the current flowing through the line connected to the secondary side is matched to phases a to c and thus I2a, I2b, and I2c, the currents are (I2a'-I2c'), (I2b'-I2a'), (I2c'), respectively. -I2b'). The current transformers 121 to 123 output current information i2a, i2b, i2c corresponding to these currents I2a, I2b, and I2c, respectively.

The direction as the reference of each current is indicated by the direction of each arrow.

2 and 3 are diagrams showing a configuration example of a transformer including a primary winding and a secondary winding of the embodiment. The transformer having the configuration shown in Figs. 2 and 3 can be applied to this embodiment.

In the tables shown in Figs. 2 and 3, a list of the transformer winding configuration and the calculation formula for calculating the phase current is described.

In the transformer winding configuration in this table, information identifying the configuration of the transformer 2 is described, and the description is based on IEC (International Electrotechnical Commission) 60076-1. For example, in the case of the "Yy0 configuration" shown at the top of the table shown in Fig. 2, both the primary winding and the secondary winding are Y-connected. An arrow attached to the "Y"-type symbol indicates the direction of the phase angle as a reference. In this case, the phase angles of the primary side and the secondary side coincide.

In addition, as an equation for calculating the phase current in the case of "Yy0 configuration", i11, i12, i13, i21, i22, i23 representing the currents of each phase in the column corresponding to "Yy0 configuration" of FIG. Six formulas shown are described. In these equations, i1a, i1b, and i1c are current information (current values) of the windings related to each phase on the primary side. Note that i2a, i2b, and i2c are current information (current values) of the windings related to each phase on the secondary side.

2 to 3, hereinafter similarly, "Dd0 configuration", "Yd1 configuration", "Dy1 configuration", "Dd2 configuration", "Dd4 configuration", "Yd5 configuration", "Dy5 configuration", "Yy6 configuration" ", "Dd6 configuration", "Yd7 configuration", "Dy7 configuration", "Dd8 configuration", "Yd9 configuration", "Dd10 configuration", "Yd11 configuration", and "Dy11 configuration" are described in order. In addition, these configurations are defined in IEC60076-1 as having a primary winding and a secondary winding. In this way, the transformers 2 have different configurations, and are classified into a plurality of types. In any configuration, the wiring of the winding is either or both of a three-phase Y connection and a Δ connection. The phases of the primary side and the secondary side are different for each configuration.

In addition, as described above, "Yd1 configuration" is included in the third column from the top of the table in FIG. 2. Hereinafter, the case of "Yd1 configuration" will be described.

Returning to Fig. 1, the transformer protection relay device 3 will be described. The transformer protection relay device 3 includes an input unit 31, an operation unit 32, and a display information generation unit 33. The input unit 31 is an example of an acquisition unit.

The input unit 31 introduces current information (i1a, i1b, i1c) on the primary side a to c output from the current transformers 111 to 113, and furthermore, a secondary side a output from the current transformers 121 to 123 Current information (i2a, i2b, i2c) of phase -c is introduced. For example, the input unit 31 generates discrete data by performing sampling and data conversion at predetermined time intervals from each introduced current information. The input unit 31 supplies the discrete data to the calculation unit 32. In this way, the input unit 31 acquires the amount of electricity corresponding to the amount of power of the transformer 2 having a winding configuration of a predetermined order.

The calculation unit 32 acquires the discrete data and performs various calculation processes set in advance, including determination of internal and external accidents of the transformer 2. The calculation unit 32 supplies the calculation result to the display information generation unit 33 to generate display information for display to the outside. The display information generation unit 33 generates display information, and causes the input/output device 320E to display the display information, for example. In addition, the arithmetic processing of the arithmetic unit 32 includes an arithmetic calculation of the difference current value for detecting an internal accident in the transformer 2. The calculation formula of the difference current value will be described later.

4 is a diagram showing an example of a configuration of an operation unit 32 according to the embodiment.

The calculation unit 32 includes, for example, a CPU 320A, a RAM (Random Access Memory) 320B, a nonvolatile memory device 320C, a portable storage medium drive device 320D, and an input/output device 320E. ) And a communication IF device 320F. In place of the CPU 320A, the calculation unit 32 may be provided with an arbitrary type of processor, and some of the components shown in FIG. 4 may be omitted.

The CPU 320A expands and executes a program stored in the nonvolatile memory device 320C or a program stored in the portable storage medium mounted on the portable storage medium drive device 320D in the RAM 320B. Various processing described below is performed. The RAM 320B is used by the CPU 320A as a working area. The nonvolatile memory device 320C is, for example, an HDD, a flash memory, or a ROM (Read Only Memory). A portable storage medium such as a DVD (Digital Versatile Disc), a CD (Compact Disc), or an SD card is mounted on the portable storage medium drive device 320D. The input/output device 320E includes, for example, an operation detection unit and a display unit as a touch panel. The communication IF device 320F communicates with an external device via a communication network or the like about the detection result or the like.

The calculation unit 32 and the display information generation unit 33 (Fig. 1) are realized by, for example, the CPU 320A executing a program. Further, the calculation unit 32 and the display information generation unit 33 may be realized by hardware such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), and FPGA (Field-Programmable Gate Array), and It may be realized through cooperation of hardware.

Returning to Fig. 1, a functional configuration of the calculation unit 32 according to the embodiment will be described.

The calculation unit 32 includes a current ratio matching calculation unit 321, a phase matching calculation unit 322, a current differential relay operation determination unit 323, an accident determination calculation unit 324, and a storage unit 325. do.

In the storage unit 325, in addition to the program, information about the calculation formula according to the current transformer ratio matching calculation, the configuration information of the transformer 2, the information about the calculation formula of the current differential relay for detecting an internal accident of the transformer 2 , Accidental flags (F1, F2, F3) and other information are stored. In addition, the configuration information of the transformer 2 includes at least information on the wiring type of the windings on the primary side and the secondary side.

The current ratio matching calculation unit 321 performs a current ratio matching calculation based on the current information of each phase introduced by the input unit 31 and the configuration information of the transformer 2, thereby generating a difference in the current value due to the current ratio. Match so that it does not. The current transformer ratio matching calculation unit 321 calculates a difference current in accordance with the current transformer ratio matching calculation. The phase matching operation unit 322 performs a phase matching operation based on current information of each phase introduced by the input unit 31 and configuration information of the transformer 2.

Here, a method of calculating the difference current Id will be described. In the calculation of the current differential relay applied to the transformer 2, a case where the α system is employed is illustrated. In addition, the target transformer 2 illustrated here is of the Y-Δ connection shown in Fig. 1 and corresponds to the "Yd1 configuration" in Fig. 2. In that case, the calculation formula of the difference current Id is as follows.

[Equation 1]

[Equation 2]

[Equation 3]

In the above formulas (1) to (3), K1 is a matching coefficient on the primary side of the transformer 2, and K2 is a matching coefficient on the secondary side of the transformer 2. As described above, the difference currents Id1, Id2 and Id3, which are the determination amounts of the current differential relay, are calculated by combining the phase currents i1a, i1b, i1c and i2a, i2b, i2c of each phase.

Here, the operation of the current differential relay when an accident is detected will be described. The relationship between the fault in the transformer 2 of the Y-Δ connection shown in Fig. 1 and the operation of the current differential relay determined based on the differential current is patterned for each occurrence of the accident. As shown in each of the following patterns, the operation of the current differential relay differs depending on the location of the accident, and the like.

First, a case where an accident occurs on the primary side (Y connection) of the transformer 2 will be described.

If the primary side accident is a phase A accident, the current differential relay of each phase operates as follows.

Phase 1: It works reliably.

Second phase: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

Phase 3: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

If the accident on the primary side is a phase B accident, the current differential relay of each phase operates as follows.

Phase 1: Operates according to the magnitude or phase of the fault current or the sensitivity of system fault detection.

Phase 2: It works reliably.

Phase 3: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

If the primary side accident is a C-phase accident, the current differential relay of each phase operates as follows.

Phase 1: Operates according to the magnitude or phase of the fault current or the sensitivity of system fault detection.

Second phase: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

Phase 3: It works reliably.

If the primary side accident is an AB phase accident, the current differential relay of each phase operates as follows.

Phase 1: It works reliably.

Phase 2: It works reliably.

Phase 3: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

If the primary side accident is a BC phase accident, the current differential relay of each phase operates as follows.

Phase 1: Operates according to the magnitude or phase of the fault current or the sensitivity of system fault detection.

Phase 2: It works reliably.

Phase 3: It works reliably.

If the primary side accident is a CA phase accident, the current differential relay of each phase operates as follows.

Phase 1: It works reliably.

Second phase: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

Phase 3: It works reliably.

In addition, if the accident on the primary side is a three-phase accident, all current differential relays in each phase operate.

Next, a case where an accident occurs on the secondary side (Δ connection) of the transformer 2 will be described.

If the accident on the secondary side is a phase A accident, the current differential relay of each phase operates as follows.

Phase 1: It works reliably.

Phase 2: Does not work.

Phase 3: It works reliably.

If the accident on the secondary side is a phase B accident, the current differential relay of each phase operates as follows.

Phase 1: It works reliably.

Phase 2: It works reliably.

Phase 3: Doesn't work.

If the accident on the secondary side is a phase C accident, the current differential relay of each phase operates as follows.

Phase 1: Does not work.

Phase 2: It works reliably.

Phase 3: It works reliably.

If the secondary side accident is an AB phase accident, the current differential relay of each phase operates as follows.

Phase 1: It works reliably.

Second phase: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

Phase 3: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

If the secondary side accident is a BC phase accident, the current differential relay of each phase operates as follows.

Phase 1: Operates according to the magnitude or phase of the fault current or the sensitivity of system fault detection.

Phase 2: It works reliably.

Phase 3: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

If the accident on the secondary side is a CA phase accident, the current differential relay of each phase operates as follows.

Phase 1: Operates according to the magnitude or phase of the fault current or the sensitivity of system fault detection.

Second phase: It operates depending on the magnitude or phase of the fault current or the sensitivity of the system fault detection.

Phase 3: It works reliably.

In addition, if the accident on the secondary side is a three-phase accident, all of the current differential relays of each phase operate depending on the magnitude of the fault current, the phase, or the sensitivity of detecting a system fault.

As described above, the accident in the transformer 2 and the operation of the current differential relay do not necessarily coincide. The current differential relay applied to the transformer protection relay device 3 matches current information in accordance with the winding configuration of the transformer and performs calculation. In order to determine an accident, only information on specific operation by calculation of the current differential relay is insufficient. Therefore, it is difficult to determine the accidental image only with information on the operation of the current differential relay.

Therefore, the current differential relay operation phase determination unit 323 and the accidental event determination operation unit 324 identify an accidental image of an internal accident in the transformer 2 by combining the phase in which the current differential relay has operated and other information. . For example, the accident determination operation unit 324 determines the maximum phase information of the current value of each phase output by the current transformer in addition to the phase on which the current differential relay has been operated determined by the current differential relay operation determination unit 323 The calculation processing used for is performed. This arithmetic processing compensates for the point in which the accidental image could not be determined by the determination processing based on the phase in which the current differential relay operated.

Specifically, a transformer protection relay device 3 according to an embodiment will be described with reference to FIGS. 1 and 5 to 8. 5 is a flow chart showing a procedure of determination processing according to the embodiment.

The current differential relay applied to the transformer protection relay device 3 of the present embodiment performs a matching calculation of current information according to the winding configuration of the transformer 2 according to either the α method or the β method of the Clark coordinate method. do. The following examples illustrate the case of the α system.

First, in step S10, the accidental judgment operation unit 324 initializes the accidental flags F1, F2, and F3. For example, the accidental flags F1, F2, F3 are provided in correspondence with each of the phases A, B, and C of the transformer 2. Each accident flag holds a logical value indicating the health of each phase. For example, each accidental flag indicates that it is an accidental event when it is set to "1". Prior to the following processing, for example, the accidental judgment operation unit 324 initializes each accidental flag to "0" indicating non-detection.

Next, in step S20, the current differential relay operation phase determination unit 323 determines the operation phase, and further calculates the amount of the operation phase. For example, the number of operating current differential relays is summarized for each wiring/accident pattern as follows.

≪Case 1: In case of a 1-phase accident in the winding of the Y connection≫

One phase of the current differential relay works reliably. The remaining two phases operate depending on the magnitude or phase of the fault current or the condition of the fault detection sensitivity.

≪Case 2: In case of a two-phase accident in the winding of the Y connection≫

The two phases of the current differential relay work reliably. The other phase operates depending on the magnitude or phase of the fault current or the condition of the fault detection sensitivity.

≪Case 3: In case of a 1-phase accident in the Δ wiring winding≫

The two phases of the current differential relay work reliably. The remaining one phase does not work.

≪Case 4: In case of a two-phase accident in the winding of the Δ connection≫

One phase of the current differential relay works reliably. The remaining two phases operate depending on the magnitude or phase of the fault current or the condition of the fault detection sensitivity.

In the event of an accident as described above, each of the current differential relays related to the accident operates. However, the operating phase of the current differential relay is divided into a phase that operates reliably according to the relationship between the winding configuration of the transformer 2 and the accident, and a phase that operates according to the magnitude or phase of the fault current or the conditions of the system accident detection sensitivity. do. Therefore, only the phase information on which the current differential relay has operated is insufficient as a condition for determining the number of phases in the operation of the current differential relay. So, in the embodiment, for example, the current differential relay operation phase determination unit 323 combines information on the phase in which the current differential relay operates and the phase at which the value of the difference current to be generated is maximum, and the current differential relay is Determine the phase that works reliably.

Referring to Fig. 6, a process of determining a phase in which the current differential relay of the embodiment reliably operates will be described. This processing is performed by the determination unit 323 on the operation of the current differential relay. 6 is a diagram showing a configuration example of a current differential relay operation phase determination unit 323 according to the embodiment. For example, the current differential relay operation phase determination unit 323 includes a current differential relay operation determination unit 3231, a maximum phase determination unit 3232, a logic calculation unit 3233, and a quantity calculation unit 3234. Equipped. The operation determination unit 3231 includes phase operation determination units 3231a, 3231b, and 3231c. The maximum image determination unit 3232 includes each of the maximum image determination units 3232a, 3232b, and 3232c. The logic operation unit 3233 includes parts 3233a, 3233b, and 3233c. 3233a, 3233b, and 3233c are end circuits. The said AND circuit is an example of a logic operation circuit. In addition, the AND circuit described above is an example and is not limited thereto, and can also be implemented using an OR circuit (logical calculation circuit) that outputs an OR by inverting the logic of each signal instead of this. .

Each of the phase operation determination units 3231a, 3231b, and 3231c indicates the operation determination result (operation phase information) of the current differential relay in the phase, and outputs "1" when the operation of the current differential relay is detected. Each of the maximum phase determination units 3232a, 3232b, 3232c indicates the determination result of the maximum phase of the value of the difference current generated by the accident, and outputs "1" when it is detected that the phase is the maximum phase from the value of the difference current. do.

In addition, the maximum phase of the value of the difference current is determined as follows. For example, an image that satisfies the following determination formula is the maximum image.

1st phase: Id1≥Max(Id1, Id2, Id3) x Kd ... (4)

2nd phase: Id2≥Max(Id1, Id2, Id3) x Kd ... (5)

3rd phase: Id3≥Max(Id1, Id2, Id3) x Kd ... (6)

According to the above equation (4), it is determined whether the difference current Id1 of the first phase is equal to or greater than the value obtained by multiplying the maximum current value among the difference currents Id1, Id2, and Id3 of each phase by an integer Kd. . As shown in equations (5) and (6), the same applies to the second and third phases.

It cannot be said that the phase to be determined as the phase in which the value of the difference current is the maximum (maximum phase) is necessarily narrowed down to any one of the first, second, and third phases. Therefore, in the present embodiment, the narrowing is not limited to only one phase, and a phase having a relatively large difference current value is set as the maximum phase.

For example, in the case of a three-phase accident, considering that Id1, Id2, and Id3 become almost equal values, an integer Kd (0<Kd≤1) determined as a predetermined real value is prepared, and the value of the difference current is The phase in which the difference current that is more than Kd times the difference current of the largest phase is generated is also established as the maximum phase.

For example, the phase operation determination unit 3231a outputs a logic "1" when the "first phase" is operated according to the operation determination of the current differential relay. For example, the logic "1" may be the H (high) level of the electric signal. Further, the maximum phase determination unit 3232a outputs a logic "1" when the determination result of the maximum phase based on the difference current is the maximum phase in the first phase. In the AND circuit 3233a, a first input terminal is connected to an output terminal of the phase operation determination unit 3231a, and a second input terminal is connected to an output terminal of the maximum phase determination unit 3232a. When the AND circuit 3233a receives the logic "1" from both the phase operation determination unit 3231a and the maximum phase determination unit 3232a, it outputs the logic "1".

Similarly to other phases, the AND circuit 3233b outputs a logic "1" when it receives a logic "1" from both of the phase operation determination unit 3231b and the maximum image determination unit 3232b. When the AND circuit 3233c receives the logic "1" from both the phase operation determination unit 3231c and the maximum phase determination unit 3232c, it outputs a logic "1".

Each input terminal of the quantity calculating part 3234 is connected to each output terminal of the above-described end circuits 3233a, 3233b, and 3233c. The quantity calculation unit 3234 receives the respective outputs from the AND circuits 3233a, 3233b, and 3233c, and calculates the quantity of the AND circuits outputting the logic &quot;1&quot;.

Through the above logic operation processing, the current differential relay operation phase determination unit 323 determines a phase in which the current differential relay reliably operates, and obtains information on the number of phases that have been operated.

Returning to Fig. 5, the description of the process continues. Based on the information on the operation of the current differential relay calculated in step S20, the accident determination operation unit 324 next determines the number of operating current differential relays that operate when a transformer accident occurs (step S30). ). Accordingly, it is possible to determine the number of operational phases of the current differential relay in which only phases that operate reliably are counted.

From the determination result of the operational quantity of the current differential relay in step S30, when there is only one operational quantity, the accidental judgment calculation unit 324 returns “1 phase accident in the winding of the Y connection” or “Δ The accident pattern is classified by "two-phase accident in the winding of the wiring", and the process advances to step S41. In addition, when the number of operational quantities is two, the accidental judgment calculation unit 324 divides the accident pattern into ``a two-phase accident in the winding of the Y connection'' or ``a single-phase accident in the winding of the Δ connection'', The process advances to step S42. The processing of step S41 and step S42 includes, for example, a determination processing of the type of connection of the primary winding by the accident determination operation unit 324 (step S40). Details of the processing of step S41 and step S42 will be described later.

After completing the processing of step S40, the accidental determination operation unit 324 switches the determination object to the secondary winding and performs the processing of step S50. Step S50 includes the processing of step S51 and step S52. The processing of step S51 and step S52 is the same as the processing of the above-described step S41 and step S42 in which the primary winding is the determination object. When the accidental judgment operation unit 324 finishes the processing of step S50, the processing advances to step S80.

In addition, when the number of operational quantities is three, the accidental determination operation unit 324 determines that it is a three-phase accident that has occurred in each phase ABC, and sets the accidental flags F1, F2, and F3 (step S70).

When the number of motions is 0, the accidental judgment operation unit 324 determines that no accident has occurred, and does not set the accidental flags F1, F2, and F3.

When the operation of the current differential relay is not detected in step S30, or after completing the processing of step S50 or step S70, the accidental accident determination operation unit 324 is based on the state of the accidental flags (F1, F2, F3). Then, the result of the determination that an accident has occurred is output on the accidental flag in which "1" is set (step S80), and a series of processing shown in the same drawing is completed. For example, the transformer protection relay device 3 provides information capable of identifying an accident of a system accident occurring in the system of the transformer 2 as a result of the above determination by a display unit such as the input/output device 320E. Can be displayed outside. From this display, it is possible to obtain information specifying an accident, and it becomes possible to quickly advance the analysis of the accident state.

Next, an example of a more specific process of step S41 (S51) described above is illustrated. 7 is a flow chart showing a more specific procedure of processing in step S41 in FIG. 5. The processing shown here is carried out in a mode in which the number of the current differential relays in operation is one (step S30).

First, the accident determination operation unit 324 determines the type of wiring of the transformer winding. For example, the accident determination operation unit 324 determines whether or not the wiring type of the primary winding is a Y connection (step S411). In the transformer protection relay device 3, information on the type of connection used for this determination is Y connection or Δ connection information as configuration information of the transformer 2 in order to determine the configuration of the transformer 2 to be protected. . Alternatively, the operator may set the connection information as a correction item, and the accidental judgment calculation unit 324 may use these information to determine whether it is a Y connection or a Δ connection.

When the wiring type of the primary winding is Y wiring, the accidental judgment calculating unit 324 determines whether the number of the maximum phase of the current value is one in the primary side of the transformer winding (step S412).

In the above case, the accident determination operation unit 324 determines that the detected phase 1 is an accident, and among the accident flags (F1, F2, F3), the phase related to the "transformer primary current maximum phase" "1" is set to the flag (step S413). For example, the accident determination operation unit 324 uses, for example, the maximum phase information of the current value of each phase for each winding to determine whether it is a 1-phase accident or a 2-phase accident, and the following equations (7) to The image that Equation (9) holds is defined as the thought image.

≪Equation for determining the maximum phase of the current value of each phase of the transformer primary winding≫

Phase A: i1a≥Max(i1a, i1b, i1c)×Kc… (7)

Phase B: i1b≥Max(i1a, i1b, i1c)×Kc… (8)

Phase C: i1c≥Max(i1a, i1b, i1c)×Kc… (9)

According to the above equation (7), it is determined whether the current i1a of the A phase is equal to or greater than a value obtained by multiplying the maximum current value of the currents i1a, i1b and i1c of each phase by an integer Kc. As shown in formulas (8) and (9), the B phase and C phase are the same.

Also, for the determination of the current value of each phase, as in the case of the determination of the maximum phase of the value of the difference current described above, determination processing in consideration of a multi-phase accident is performed. Here, the constant Kc (0<Kc≦1) is provided, and the phase in which the current value in which the value of the phase current is Kc times or more of the largest phase current value is established is also established as the maximum current phase.

When the wiring type of the primary winding is Δ wiring, the accidental determination calculating unit 324 determines whether the number of the maximum phases of the current value is two on the primary side of the transformer winding (step S414).

In the above case, the accident determination operation unit 324 determines that the detected two phases are accidental, and among the accidental flags (F1, F2, F3), the phase related to the ``transformer primary current maximum phase'' "1" is set to the flag (step S415).

Incidentally, the accident determination operation unit 324 determines that the number of the maximum phase of the current value is not one from the determination result of step S412, when the processing of step S413 is finished, the maximum value of the current value from the determination result of step S414 In the case where it is determined that the quantity is not two or when the processing of step S415 is completed, a series of processing shown in the same drawing is finished.

Also, when the above-described processing is used for determination of the secondary winding, the same determination as that of the primary winding is performed to determine the accident. The maximum phase information of the current value of each phase on the secondary side of the transformer 2 is calculated using the following equations (10) to (12) similarly to the determination on the primary side.

≪Equation for determining the maximum phase of the current value of each phase of the transformer secondary winding≫

Phase A: i2a≥Max(i2a, i2b, i2c)×Kc… (10)

B phase: i2b≥Max(i2a, i2b, i2c)×Kc… (11)

Phase C: i2c≥Max(i2a, i2b, i2c)×Kc… (12)

In addition, when a tertiary-side winding is present in the transformer 2, a judgment method similar to that of the secondary-side winding can be applied.

The accident determination operation unit 324 performs accident determination processing when the number of operating current differential relays is one by the above processing. This processing is performed on the primary side and the secondary side, respectively, and in each processing, an image in which an accidental event flag is set can be specified as an accidental event.

Next, an example of a more specific process of step S42 (S52) described above is illustrated. 8 is a flow chart showing a more specific procedure of processing in step S42 in FIG. 5. The processing shown here is performed in the case of a mode in which the operational quantity of the current differential relay is two.

First, the accident determination operation unit 324 determines the type of wiring of the transformer winding. For example, the accident determination operation unit 324 determines whether or not the wiring type of the primary winding is a Y connection (step S421).

When the wiring type of the primary winding is Y wiring, the accidental judgment calculating unit 324 determines whether the number of the maximum phases of the current value is two on the primary side of the transformer winding (step S422).

In the above case, the accident determination operation unit 324 determines that the detected two phases are accidental, and among the accidental flags (F1, F2, F3), the phase related to the ``transformer primary current maximum phase'' A flag is set (step S423).

When the wiring type of the primary winding is Δ wiring, the accidental judgment calculating unit 324 determines whether the number of the maximum phase of the current value is one on the primary side of the transformer winding (step S424).

In the above case, the accident determination operation unit 324 determines that the detected phase 1 is an accident, and among the accident flags (F1, F2, F3), the phase related to the "transformer primary current maximum phase" A flag is set (step S425).

Incidentally, the accident determination operation unit 324 determines that the number of the maximum phases of the current value is not two from the determination result of step S422, when the processing of step S423 is finished, the maximum value of the current value from the determination result of step S424 In the case where it is determined that the quantity is not one or the case where the processing in step S425 is completed, a series of processing shown in the same drawing is completed.

The accident determination operation unit 324 performs the accident determination processing in the case of two operational phases by the above processing. The accidental-cause determination operation unit 324 performs this processing on the primary side and the secondary side, respectively, and specifies, in each of the processes, an image in which an accidental-cause flag is set as an accidental image.

According to the first embodiment described above, the transformer protection relay device 3 is at least between the phase current on the primary side of the transformer 2 and the phase current on the secondary side from the amount of electricity according to the amount of power of the transformer having a winding configuration of a predetermined order. The difference current is calculated based on information on a predetermined winding configuration, and the operation of the current differential relay of the transformer 2 is determined, and the information on the operation of the operated current differential relay and the calculated difference current value Based on the maximum differential current phase information on the phase exceeding the predetermined value, the operational quantity for which the current differential relay reliably operates is calculated, and at least the operational quantity based on the operational information and the winding of the transformer 2 The transformer in which the accident occurred by determining the accident of the system accident caused by the transformer 2 based on the information of the phase current maximum phase information and the information of the wiring type of each phase in which the current value of each phase exceeded a predetermined value. The accident in (2) can be judged. For example, when the number of phases detected by the current differential relay is three, the transformer protection relay device 3 adds three phases as an accident. In addition, when the number of phases detected by the current differential relay is 2, the number of phases according to the phase current maximum phase information in the Y-connection winding and the phase current maximum phase information in the Δ connection winding are two phases. One individual award is added as an accidental award. In addition, the transformer protection relay device 3 is similarly detected by the phase current maximum phase information in the winding of the Y connection, and the phase current maximum phase information in the winding of the Δ connection. An award with two awards is added as an accident. By performing the above-described processing, the transformer protection relay device 3 enables identification of an accident in the transformer 2 in which an accident has occurred, thereby improving convenience in maintenance and operation.

In addition, in order to apply the transformer protection relay device 3 to a plurality of types of transformers, the conditions for determining the accident of a system accident occurring in the system of the transformer 2, the winding configuration of the transformer 2 Just use the information. Accordingly, regardless of the type of the transformer 2, the transformer protection relay device 3 can be common.

(Second embodiment)

A transformer protection relay device according to an embodiment will be described with reference to FIGS. 9 to 11.

9 is a diagram showing a configuration of a transformer protection relay system 1A according to an embodiment. The transformer protection relay system 1A includes a transformer 2A, a transformer protection relay device 3A, current transformers 111 to 113, current transformers 121 to 123, and current transformers 131 to 133.

The transformer 2A includes a primary winding, a secondary winding and a tertiary winding insulated from each other, and the specifications of the primary winding, the secondary winding and the tertiary winding are all three-phase AC specifications. Current transformers 111 to 113 are provided on the primary side of the transformer 2A, current transformers 121 to 123 are provided on the secondary side, and current transformers 131 to 133 are provided on the third line.

In addition, in the transformer 2A shown in Fig. 9, the connection of the primary winding is a neutral grounded Y connection, whereas the connection of the secondary winding and the connection of the tertiary winding are non-grounded Δ connection. The configuration of the transformer 2A is called "Yd1d1 configuration" (Fig. 10). The wiring of this transformer 2A shows an example, and is not limited to this.

10 is a diagram showing a configuration example of a transformer 2A including a primary winding, a secondary winding, and a tertiary winding of the embodiment. The transformer having the configuration shown in Fig. 10 can be applied to the present embodiment. In the table shown in Fig. 10, a list of the transformer winding configuration and the calculation formula for calculating the phase current is described.

In the transformer winding configuration, information identifying the configuration of the transformer 2A is described, and the description is in accordance with IEC60076-1. For example, in the case of the "Yd1d1 configuration" shown in the third stage from the top, the primary winding is a Y connection, and the secondary winding and the tertiary winding are both Δ connections. The arrows attached to the symbols of the "Y" shape and the "Δ" shape indicate the direction of the phase angle as a reference. In this case, the phase angles of the secondary side and the tertiary side coincide. When the phase angle of the primary side is taken as a reference, the phase angles of the secondary side and the tertiary side are delayed by 30 degrees.

In addition, as an equation for calculating the phase current in the case of the "Yd1d1 configuration", i11, i12, i13, i21, i22, i23, i31, which indicate the currents of each phase in the column corresponding to the "Yd1d1 configuration" in FIG. Nine equations representing each of i32 and i33 are described. In these equations, i1a, i1b, and i1c are current values of the windings related to each phase on the primary side. In addition, i2a, i2b, and i2c are current values of the windings related to each phase on the secondary side. Note that i3a, i3b, and i3c are current values of the windings related to each phase on the tertiary side.

In the same drawing, in addition to the above "Yd1d1 configuration", in order from above, "Yy0d1 configuration", "Yy0d11 configuration", "Yd11d11 configuration", "Dy11d0 configuration", "Dy1d0 configuration", "Dd0d0 configuration", and "Yy0y0 configuration". Configuration” is described. In addition, these configurations are defined in IEC60076-1 as having a primary winding, a secondary winding, and a tertiary winding. These transformers are classified into a plurality of types with different configurations. In the transformers of each configuration, the wiring of the winding is either or both of the Y connection and the Δ connection, and the phases of the primary side, the secondary side, and the tertiary side are different depending on the configuration.

The transformer protection relay device 3A includes an input unit 31A, an operation unit 32A, and a display information generation unit 33. For example, the calculation unit 32A is configured similarly to the calculation unit 32 (Fig. 4).

The input unit 31A introduces the current information i1a, i1b, i1c on the primary side a to c output from the current transformers 111 to 113, and furthermore, a secondary side a output from the current transformers 121 to 123 Current information (i2a, i2b, i2c) of phase -c and current information (i3a, i3b, i3c) of phases a to c output from the current transformers 131 to 133 are introduced.

The calculation unit 32A includes a current ratio matching calculation unit 321A, a phase matching calculation unit 322A, a current differential relay operation determination unit 323A, an accident determination calculation unit 324A, and a storage unit 325A. do. The current transformer ratio matching calculation unit 321A, the phase matching calculation unit 322A, the current differential relay operation determination unit 323A, the accident determination calculation unit 324A, and the storage unit 325A are the current transformer ratio shown in FIG. They correspond to a matching operation unit 321, a phase matching operation unit 322, a current differential relay operation condition decision unit 323, an accident condition decision operation unit 324, and a storage unit 325, respectively. The calculation unit 32A makes a determination about the transformer 2A having a primary winding, a secondary winding, and a tertiary winding insulated from each other. That is, the calculation unit 32A acquires the discrete data of the primary side, the secondary side, and the tertiary side from the input unit 31A, and performs various arithmetic processes set in advance, including internal and external accident determination of the transformer 2A. The calculation unit 32A supplies the result of the calculation result to the display information generation unit 33 to generate display information for display to the outside. The display information generation unit 33 generates display information, and causes the input/output device 320E to display the display information, for example. In addition, the processing according to the accidental judgment on the third side of the calculation unit 32A is the same as the processing according to the accidental judgment on the secondary side described above.

Next, a transformer protection relay device 3A according to an embodiment will be described with reference to FIG. 11. 11 is a flow chart showing a procedure of determination processing according to the embodiment.

The transformer protection relay device 3A performs the processing of step S50 after performing the processing from step S10 to step S40. Step S50 includes the processing of step S51 and step S52. The processing of Step S51 and Step S52 is the same as the processing of Step S41 and Step S42 described above.

The transformer protection relay device 3A performs the process of step S60 after performing the process of step S50. Step S60 includes the processing of step S61 and step S62. The processing of step S61 and step S62 is the same as the processing of step S41 and step S42 described above. When the accidental judgment calculation unit 324 finishes the process of step S60, the process advances to step S80.

The transformer protection relay device 3A is determined based on the state of the accidental flag when the operation of the current differential relay in step S30 is not detected, or after the processing in step S60 or step S70 is completed. Is outputted (step S80), and a series of processing shown in the same drawing is completed. In addition, for explanation of the processing of each step other than the above, refer to the description of the flowchart shown in FIG. 5.

According to the second embodiment described above, in addition to exhibiting the same effects as in the first embodiment, the transformer protection relay device 3A can make the transformer 2A having a tertiary winding as an object of protection.

Although several embodiments of the present invention have been described, these embodiments have been presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. If these embodiments and their modifications are included in the scope and summary of the invention, similarly, they are included in the invention described in the claims and their equivalent ranges.

For example, terminal devices other than the transformer protection relay device 3 may receive the display information generated by the display information generation unit 33 from the transformer protection relay device 3 and display the display information.

1, 1A: transformer protection relay system
2, 2A: transformer
3, 3A: transformer protection relay device
31, 31A: input section (acquisition section)
32, 32A: operation unit
33: display information generation unit
111 to 113, 121 to 123, 131 to 133: current transformer
321: current transformer ratio matching operation unit
322: phase matching operation unit
323: Current differential relay operation phase determination unit
324: accident judgment calculation unit
325: memory

Claims (5)

An acquisition unit for acquiring an amount of electricity according to the amount of electricity of a transformer having a winding configuration of a predetermined order;
A differential current between at least a phase current on a primary side of the transformer and a phase current on a secondary side of the transformer is calculated from the obtained amount of electricity based on the information on the predetermined winding configuration, and an operation state of the current differential relay of the transformer is calculated. It has an operation unit for determining,
The calculation unit,
An operation in which the current differential relay reliably operates based on information on the operation phase of the operated current differential relay and information on the maximum differential current phase for a phase in which the calculated differential current value exceeds a predetermined value. Calculate the number of phases,
At least, based on the number of operational phases, phase current maximum phase information about a phase in which the current value of each phase for each winding of the transformer exceeds a predetermined value, and information on the type of wiring of the winding, the transformer is A transformer protection relay device that determines the accident of a system accident. The method of claim 1,
The calculation unit,
A transformer protection relay device configured to determine an accidental event of a system accident due to the transformer based on the number of operating phases, information on the winding configuration of the transformer, and the phase current maximum phase information. The method of claim 1,
Transformer protection relay device further comprising a display information generating unit for generating information indicating the accident of the system accident due to the transformer. The method of claim 1,
The calculation unit,
A transformer protection relay device that calculates the differential current by using the α method or β method of the Clark coordinate method in the matching operation method of the current differential relay. The method of claim 4,
The transformer has a plurality of order windings, each of the order windings is formed in three phases, and the wiring of the windings is either or both of a Y connection and a Δ connection,
The calculation unit,
A matching operation using the α method of Clark's coordinate method is performed in the matching operation method,
A logical operation based on the operation information and the difference current maximum phase information is performed for each of the phases using the result of the matching operation,
If the number of phases detected as satisfying a predetermined condition from the result of the logical operation is 3, it is determined that all phases of the transformer are the accidental phases,
When the number of detected phases is two, a phase in which the number of phases according to the phase current maximum phase information is two in the winding of the Y connection and a phase in which the number of phases by the phase current maximum phase information is one in the winding of the Δ connection. , It is determined that it is the above accident,
When the number of detected phases is 1, a phase in which the number of phases by the phase current maximum phase information is 1 in the winding of the Y connection and a phase in which the number of phases by the phase current maximum phase information is 2 in the winding of the Δ connection. And a transformer protection relay device that determines that the accident is the above.

Images