JP2010166770A - Overcurrent relay device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overcurrent relay device, capable of shortening an operation time limit and preventing the time for removing a short-circuit fault from changing, depending on the situation of the accident, when a short-circuit fault occurs within the range of a time limit element. <P>SOLUTION: The overcurrent relay device used for protecting a power transmission line in a power system from a short-circuit fault includes: operation time limit deciding means 12<SB>1</SB>-12<SB>3</SB>, 13<SB>1</SB>-13<SB>3</SB>, 14<SB>1</SB>-14<SB>3</SB>for obtaining the operation time limit of the overcurrent relay device, in accordance with the range designated time limit characteristic curve (a), based on the amplitude value of a fault current in three-phase short-circuit fault; and a fault situation determining means 15 for determining the fault is a three-phase short-circuit fault or a two-phase short-circuit failure based on the amplitude value of the fault current in a short-circuit failure. If the result of determination of the fault situation determining means 15 shows that this is a two-phase short-circuit fault, the operation time limit deciding means 12<SB>1</SB>-12<SB>3</SB>, 13<SB>1</SB>-13<SB>3</SB>, 14<SB>1</SB>-14<SB>3</SB>obtain the operation time limit of the overcurrent relay device, in accordance with the range designated time limit characteristic curve (a), based on a value obtained by dividing the amplitude value of the fault current in the short circuit fault by 3<SP>1/2</SP>/2. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an overcurrent relay device, and more particularly, to an overcurrent relay device suitable for use in protection in the event of a short circuit accident of a transmission line in an electric power system.

  In general, an overcurrent relay (OC) used for protection in the case of a power line short circuit accident in an electric power system is based on the amplitude value of the accident current at the time of a three-phase short circuit accident. The operation is performed in accordance with the operation time characteristic determined according to the operation time characteristic. For this reason, in consideration of cooperation with the overcurrent relay device in the next section, there are cases where the protection range becomes narrow or the operation time period becomes long.

For example, the first overcurrent relay device (OC) 110 ₁ installed on the power source 1 side as shown in FIG. 8A and the rear side of the first overcurrent relay device 110 ₁ (opposite of the power source 1) In the electric power system in which the second overcurrent relay device (OC) 110 ₂ installed on the side) is time-coordinated to protect the transmission line, the maximum fault current (3 In order to achieve timed coordination in the case of a phase short circuit accident), the operating time limits of the first and second overcurrent relay devices 110 ₁ and 110 ₂ are in accordance with the operating time characteristic curves A and B shown in the graph of FIG. It is determined.
Here, the operating time characteristic curves A and B indicate that the first and second circuit breakers 4 ₁ and 2 when the short circuit accident occurs in the vicinity of the first and second overcurrent relay devices 110 ₁ and 110 ₂ , respectively. In order to instantaneously cut off 4 ₂ and to secure the necessary protection range in the time limit element operation range of the first and second overcurrent relay devices 110 ₁ and 110 ₂ , the fixed time characteristic and time limit in the instantaneous element operation range It is defined by the combination with the normal anti-time characteristic in the element operation range (in the strong anti-time characteristic, the protection range in the time element operation range is narrowed).
The horizontal axis of this graph is the total impedance (synthetic impedance)% Z corresponding to the distance from the power source 1.

Therefore, if a three-phase short circuit accident occurs behind the second overcurrent relay device 110 ₂ and a 30 A fault current I flows in each phase of the transmission line, a white circle is shown in FIG. 8B. In addition, the second overcurrent relay device 110 ₂ close to the fault point instantaneously follows the operating time characteristic curve B based on the fault current I input from the _second current transformer 3 _{2. When the second} overcurrent relay device 110 ₂ is not operated, the first overcurrent relay device 110 ₁ is input from the _first current transformer 3 _1. by blocking the first breaker 4 ₁ after operation timed (approximately 0.6 s) has elapsed in accordance with the operating time characteristics curve a on the basis of the fault current I, has secured protection performance and protection reliability of the transmission line.

However, since the first overcurrent relay device 110 ₁ operates according to the normal inverse time characteristic, the operation time becomes longer, and it takes time to break the _first circuit breaker 4 ₁ .

If a two-phase short-circuit accident occurs at the same accident point, the accident current I is 3 ^1/2 / 2 times the accident current (30 A) at the time of the three-phase short-circuit accident = about 0.866 times (about 26 A) (That is, the total impedance% Z on the horizontal axis in FIG. 8C apparently increases), the first and second overcurrent relay devices 110 ₁ and 110 ₂ are in a three-phase short circuit accident. The operation time characteristic curves A and B set for time cooperation are operated at the operation time points indicated by the black circles instead of the white circles in FIG. As a result, the second overcurrent relay device 110 _{2 that} is close to the accident point shuts off the second circuit breaker 4 ₂ after an operating time period of about 0.35 s, and the second overcurrent relay device 110 ₂ if not work, the first overcurrent relay device 110 ₁ initially prevents the first breaker 4 ₁ after operation timed about 1.1 seconds, compared to when the three-phase short-circuit fault first And the timing which interrupts | blocks the 2nd circuit breakers 4 ₁ and 4 ₂ is delayed, and it becomes impossible to secure the protection performance and the protection reliability.
In other words, at the time of a two-phase short-circuit accident, the first and second overcurrent relay devices 110 ₁ and 110 ₂ are not the operation time characteristic curves A and B, but the operation time characteristic curve shown by a one-dot chain line in FIG. Since the operation is based on A ′ and B ′, the instantaneous element operation range of the first and second overcurrent relay devices 110 ₁ and 110 ₂ is shortened and the time limit element operation time period is extended.

9A, the short-circuit distance relay device (DZ) 210 installed on the power source 1 side and the overcurrent relay device (OC) 220 installed behind the short-circuit distance relay device 210. In a power system that protects the transmission line with time cooperation, if the time cooperation is taken with the maximum fault current (at the time of a three-phase short-circuit fault) where the operation time of the time limit element is the shortest, the short-circuit distance relay device 210 and The operation time limit of the overcurrent relay device 220 is set so as to be the operation time characteristic curves C and D shown in the graph of FIG.
Therefore, at the time of a two-phase short-circuit accident, the overcurrent relay device 220 operates according to the operation time characteristic curve D ′ indicated by the one-dot chain line in FIG. In this case, it becomes impossible to achieve timed coordination between the short-circuit distance relay device (DZ) 210 and the overcurrent relay device (OC) 220.

  Therefore, the short-circuit distance relay device 210 is operated in accordance with the operation time characteristic curve C ′ indicated by a one-dot chain line in FIG. The two-stage operation region of the short-circuit distance relay device 210 (in this example, the range of operation time is about 0.3 s) is narrowed, and the short-circuit distance relay device 210 is not in operation of the overcurrent relay device 220. Since the far-end protection is performed in a three-stage operation region (in this example, the operation time limit is in a range of about 0.8 s), the protection reliability is lowered.

In addition, in Patent Document 1 below, in order to easily and quickly set an operation characteristic that enables protection coordination, a circuit voltage of a load that is protected by a higher-order overcurrent relay, a time limit is set. Enter the element type, set current tap value, operating time-dial value, instantaneous element operating current value and CT ratio, and load the circuit voltage, load type, load capacity, and load that the overcurrent relay protects. The short circuit capacity and CT ratio are input, and based on these input information, the logic operation circuit enables operation coordination with the host overcurrent relay (the type of time limit element, the set current tap) An overcurrent relay and an overcurrent protection system that obtain a value, an operating time dial value, and an instantaneous element operating current value) and display them on a display unit are disclosed.
In Patent Document 2 below, in order to eliminate the complexity of the review and review work including the operation management associated with the change in the operation mode of the distribution system, each customer uses a branch distribution line branched from the distribution line bus. When a short circuit occurs in a power distribution system that can be selected between a dendritic operation that distributes power to the loop and a loop operation that combines dendritic distribution lines, an overcurrent detection element disconnects the shorted distribution line from the distribution system based on the distribution line current In the distribution line short circuit protection relay device that outputs (FCB trip signal) to each distribution line outlet circuit breaker, the short circuit protection relay includes an overcurrent detection element having an inverse time limit characteristic during distribution line dendron operation, and a distribution line loop Short distribution line with overcurrent detection element with stronger inverse time characteristic during operation and loop operation information capture means to selectively switch the output of overcurrent detection element according to loop operation status Protective relay device is disclosed.
In Patent Document 3 below, the instantaneous element determination unit and the time limit element determination unit operate with respect to the current value of the current input unit in order to easily realize protection coordination in the short-circuit region in multi-stage time difference settling. An overcurrent relay is disclosed in which the operation time characteristic is controlled by the operation determination unit in combination with the state of the operation characteristic switching means based on the signal from the determination unit.
In Patent Document 4 below, there is an optimum protection environment corresponding to a power supply state that makes it easy to change a set value in an overcurrent protection relay provided in a power receiving / transforming facility provided with an emergency generator that is arranged in parallel with a commercial power supply. The overcurrent protection relay has a built-in settling pattern used when supplying commercial power that can be set and changed by an external electrical signal and a settling pattern used when feeding an emergency generator. A power supply state determination circuit that determines whether the power supply state of the facility is a commercial power supply or an emergency generator, and the settling pattern is switched to an appropriate settling pattern according to the power supply determined by the power supply state determination circuit. An overcurrent protection relay with a setting pattern automatic switching function provided with a changeover switch is disclosed.
JP-A-7-322475 JP 2004-254369 A JP-A-8-205382 JP-A-9-135527

  As described above, in the overcurrent relay device, the overcurrent relay device is set to operate in accordance with the operation time characteristic curve defined by the combination of the fixed time characteristic in the instantaneous element operation range and the normal inverse time characteristic in the time element operation range. Therefore, when a short circuit accident occurs in the time limit element operation range, there is a problem that the operation time period becomes exponentially longer, and the operation time period set based on the magnitude of the accident current at the time of the three-phase short circuit accident Therefore, there is a problem of adversely affecting the equipment because the operation time period is delayed in the case of a two-phase short circuit accident and it takes time to remove the accident.

  It is an object of the present invention to shorten the operation time when a short circuit accident occurs in the time limit element operation range and to prevent the accident removal time from being changed depending on the accident mode (three-phase short circuit accident and two-phase short circuit accident). An object of the present invention is to provide an overcurrent relay device capable of performing the above.

The overcurrent relay device of the present invention is an overcurrent relay device used for protection in the event of a short circuit accident of a transmission line in an electric power system, and is based on the amplitude value of the accident current at the time of a short circuit accident. Comprising an operation time period determining means for determining an operation time period of the overcurrent relay device according to an operation time characteristic that determines an operation time period of the device, wherein the operation time characteristic is a range-designated operation time-characteristic, and the range-designated operation time-characteristic The operation time characteristic in the instantaneous element operation range is defined by the fixed time characteristic, and the operation time characteristic in the time element operation range of the range designation operation time characteristic is constant due to the total impedance from the power source (1). The fixed time characteristic, the proportional time characteristic in which the operation time period increases in proportion to the total impedance, and the operation time period is constant due to the total impedance. Characterized in that it is defined by a combination of Teikiri state characteristic of.
The overcurrent relay device of the present invention is an overcurrent relay device used for protection in the event of a short circuit accident of a transmission line in an electric power system, and is based on the amplitude value of the accident current at the time of a short circuit accident. An operation time period determining means for determining an operation time period of the overcurrent relay device according to an operation time characteristic that determines an operation time period of the device, wherein the operation time characteristic is a proportional operation time characteristic; The operation time characteristic in the element operation range is defined by the fixed time characteristic, and the operation time characteristic in the element operation range increases in proportion to the total impedance from the power source (1). It is defined by characteristics.
The overcurrent relay device of the present invention is an overcurrent relay device used for protection in the event of a short circuit accident of a transmission line in an electric power system, and is based on the amplitude value of the accident current at the time of a short circuit accident. Comprising an operation time period determining means for determining an operation time period of the overcurrent relay device according to an operation time characteristic that determines an operation time period of the device, wherein the operation time characteristic is a multistage operation time characteristic, The operation time characteristic in the element operation range is defined by a fixed time characteristic, and the operation time characteristic in the time element operation range of the multistage operation time characteristic is defined by a combination of a plurality of operation time characteristics.
The overcurrent relay device of the present invention is an overcurrent relay device (50 ₁ , 50 ₂ ) used for protection in the event of a short circuit accident of a transmission line in an electric power system, and the amplitude of the accident current at the time of a three-phase short circuit accident. Of the overcurrent relay according to a range-designated operation time characteristic, proportional operation time characteristic or multistage operation time characteristic that determines the operation time limit of the overcurrent relay device based on the value or the amplitude value of the fault current at the time of a two-phase short-circuit fault An operation time period determining means (12 _{1 to} 12 ₃ , 13 _{1 to} 13 ₃ , 14 _{1 to} 14 ₃ ) for determining an operation time period, an accident mode determining means (15) for determining whether a three-phase short-circuit accident or a two-phase short-circuit accident; And the operation time determination means converts the amplitude value of the accident current at the time of the two-phase short-circuit accident into the amplitude value of the accident current at the time of the three-phase short-circuit accident according to the determination result in the accident aspect determination means, or Amplitude value of accident current at the time of three-phase short circuit accident Converted into the amplitude value of the accident current at the time of the two-phase short circuit accident, and based on the converted amplitude value of the accident current, the overcurrent relay is performed according to the range designation operation time characteristic, the proportional operation time characteristic, or the multistage operation time characteristic. The operation time limit of the electric device is obtained.
Here, the operation time characteristic in the instantaneous element operation range of the range designation operation time characteristic is defined by the fixed time characteristic, and the operation time characteristic in the time element operation range of the range designation operation time characteristic is obtained from the power source (1). The first fixed time characteristic in which the operation time is constant according to the total impedance, the proportional time characteristic in which the operation time increases in proportion to the total impedance, and the second fixed time characteristic in which the operation time is constant according to the total impedance. The operation time characteristic in the instantaneous element operation range of the proportional operation time characteristic is defined by the fixed time characteristic, and the operation time characteristic in the time element operation range of the proportional operation time characteristic is proportional to the total impedance. Stipulated by the proportional time characteristic in which the operation time increases, Together with the operation time characteristics are defined by Teikiri time characteristics in the elements operating range when operating time characteristics of the time limit elements operating range of the multi-stage operating time characteristics may be defined by a combination of a plurality of operation limit time characteristics.
The operation time determining means divides the amplitude value of the accident current at the time of the two-phase short-circuit accident by 3 ^1/2 / 2, and thereby the amplitude value of the accident current at the time of the two-phase short-circuit accident is calculated as the accident current at the time of the three-phase short-circuit accident. You may convert into the amplitude value of.
The operation time determining means multiplies the amplitude value of the accident current at the time of the three-phase short-circuit accident by 3 ^1/2 / 2, thereby obtaining the accident current value at the time of the two-phase short-circuit accident. You may convert into the amplitude value of.
The operation time determination means includes time limit element operation determination means (12 _{1 to} 12 ₃ ) for determining whether or not the amplitude value of the accident current at the time of the short circuit accident is equal to or greater than a settling time limit tap value; Time processing means (13 _{1 to} 13 ₃ ) for obtaining an operation time limit of the overcurrent relay device in accordance with a characteristic, the proportional operation time characteristic or the multi-stage operation time characteristic, and the determination result in the accident mode determination means is three-phase In the case of a short-circuit accident, the time-limit element operation determination means determines whether or not the amplitude value of the accident current at the time of the short-circuit accident is equal to or greater than a settling time limit tap value, and the time-limit processing means The operation of the overcurrent relay device according to the range-designated operation time characteristic, the proportional operation time characteristic or the multistage operation time characteristic based on the amplitude value of the fault current input from the time element operation determination means If the determination result in the accident mode determination means is a two-phase short-circuit accident, the time-limit element operation determination means determines that the fault current amplitude value in the short-circuit accident is equal to or greater than the settling time limit tap value. And the time processing means is based on the fault current amplitude value input from the time element operation determination means, the range-designated operation time characteristic, the proportional operation time characteristic, or the multistage operation time period. The operation time limit of the overcurrent relay device is obtained according to the characteristics, and the accident current amplitude converted value, which is a value obtained by dividing the amplitude value of the accident current at the time of the short circuit accident by 3 ^1/2 / 2, is calculated. It is determined whether or not an accident current amplitude conversion value is equal to or greater than the settling time limit tap value, and the range-designated operation time characteristic based on the accident current amplitude conversion value input from the time element operation determination means The above The operation time limit of the overcurrent relay device may be obtained according to the proportional operation time characteristic or the multistage operation time characteristic.
The operation time limit determining means includes instantaneous element operation determining means (14 _{1 to} 14 ₃ ), and when the determination result in the accident aspect determining means is a three-phase short circuit accident, It is determined whether or not the amplitude value of the accident current at the time of the short-circuit accident is greater than or equal to the settling instantaneous tap value, and when the instantaneous element operation determination unit determines that the determination result in the accident mode determination unit is a two-phase short-circuit accident Accident current amplitude conversion value that is a value obtained by dividing the accident current amplitude value at the time of the short circuit accident by 3 ^1/2 / 2 is calculated, and the calculated accident current amplitude conversion value is equal to or greater than the settling instantaneous tap value. It may be determined whether or not.
The accident mode determination means determines that a three-phase short-circuit accident occurs when all of the amplitude values of the accident currents flowing through the phases of the transmission line are greater than a predetermined threshold at the time of the short-circuit accident, and a two-phase short-circuit accident otherwise. May be determined.
The overcurrent relay device of the present invention is an overcurrent relay device (50 ₁ , 50 ₂ ) used for protection in the event of a short circuit accident of a transmission line in an electric power system, and includes a circuit breaker installed on the transmission line. A trip signal generation circuit (10) for generating a trip signal for interrupting is provided, and the trip signal generation circuit converts fault current data (I _R , I _W , Based on the amplitude value of the fault current data inputted from the amplitude value calculation unit (11 _{1 to} 11 ₃ ) for obtaining the amplitude value of I _B ) and the amplitude value calculation unit, the accident mode is a three-phase short circuit accident If the accident mode determination unit (15) determines whether the short circuit accident is a three-phase short circuit accident, the amplitude value of the accident current data is settled. Determine if it is greater than or equal to the timed tap value, Write, wherein an accident appearance determining unit determines that "short-circuit failure is a two-phase short-circuit fault", the amplitude conversion value of the fault current data is a value obtained by dividing the amplitude value of the fault current data at 3 ^1/2 / 2 And a time limit element operation determination unit (12 _{1 to} 12 ₃ ) for determining whether or not the calculated converted amplitude of the fault current is equal to or greater than the settling time limit tap value, and an output of the time limit element operation determination unit In accordance with a signal, a range-designated operation time limit characteristic that determines the operation time limit of the overcurrent relay device from the amplitude value of the fault current data input from the time limit element operation determination unit or the amplitude converted value of the fault current, proportional A time processing unit for obtaining an operation time according to the operation time characteristic or the multistage operation time characteristic and outputting a time element trip signal (T1 _R , T1 _W , T1 _B ) for breaking the breaker after the determined operation time elapses (13 _{1 to} 13 ₃ ).
Here, the trip signal generation circuit outputs an instantaneous element operation determination unit (14 _{1 to} 14 ₃ ) for outputting an instantaneous element trip signal (T2 _R , T2 _W , T2 _B ) for instantaneously breaking the circuit breaker. Further, if the instantaneous element operation determination unit determines that the accident aspect determination unit determines that “the short circuit accident is a three-phase short circuit accident”, whether or not the amplitude value of the accident current data is equal to or greater than a settling instantaneous tap value. And when it is determined that “the amplitude value of the accident current data is equal to or larger than the settling instantaneous tap value”, the instantaneous element trip signal is output. If it is determined that “there is”, an amplitude conversion value of the accident current data, which is a value obtained by dividing the amplitude value of the accident current data by 3 ^1/2 / 2, is calculated, and the calculated amplitude conversion value of the accident current is the settling instantaneous Whether it is greater than or equal to the tap value The determination may output the instantaneous element trip signal and determines that "the amplitude equivalent value of the fault current data is settling instantaneous tap value or more".
Based on the tap magnification at the time of a three-phase short-circuit accident or the tap magnification at the time of a two-phase short-circuit accident instead of the operation time-limit characteristic that determines the operation time limit of the overcurrent relay device based on the amplitude value of the accident current at the time of the short-circuit accident The operation time limit characteristic that determines the operation time limit of the overcurrent relay device is used, and the operation time determination means determines the two-phase settling tap value at the time of a three-phase short-circuit accident according to the determination result in the accident aspect determination means. Convert to the setting tap value at the time of short circuit accident or convert the setting tap value at the time of two phase short circuit accident to the setting tap value at the time of three phase short circuit accident and set the converted amplitude value of the accident current at the time of the short circuit accident The tap magnification may be calculated by dividing by the tap value, and the operation time limit of the overcurrent relay device may be obtained according to the operation time characteristic based on the calculated tap magnification.
The operating time determining means multiplies the setting tap value at the time of the three-phase short circuit accident by 3 ^1/2 / 2 to convert the setting tap value at the time of the three-phase short circuit accident into the setting tap value at the time of the two-phase short circuit accident. May be.
The operation time determining means divides the setting tap value at the time of the two-phase short-circuit accident by 3 ^1/2 / 2 to convert the setting tap value at the time of the two-phase short-circuit accident into the setting tap value at the time of the three-phase short-circuit accident. May be.

The overcurrent relay device of the present invention has the following effects.
(1) By setting the operation time characteristics to range-specified operation time characteristics, proportional operation time characteristics, or multistage operation time characteristics, the operation time limit of the time limit element operation range can be shortened compared to the normal anti-time characteristics. Therefore, the operation time limit when a short circuit accident occurs in the time element operating range can be shortened.
(2) By providing the accident aspect determination means, the overcurrent relay device can be operated with an operation time period corresponding to the accident aspect, so that the accident removal time does not change depending on the accident aspect.
(3) The overcurrent relay device can be used as a short-circuit distance relay device by combining the range specifying operation time characteristic and the accident mode determination means.
(4) Since the delay of the operation time limit at the time of a two-phase short circuit accident can be suppressed, the protection performance can be improved.
(5) Since relay coordination can be facilitated, the relay operation time of the entire protection system can be shortened.
(5) Timed coordination with other overcurrent relay devices is facilitated, and timed coordination with short-circuit distance relay devices is facilitated.

For the above purpose, by setting the operation time characteristics to the range specified operation time characteristics, proportional operation time characteristics or multi-stage operation time characteristics, and overcurrent based on the amplitude value or tap magnification of the accident current at the time of three-phase short circuit accident Use range-designated operation time characteristics, proportional operation time characteristics, or multi-stage operation time characteristics to determine the operation time of the relay device. If the result of the accident mode determination means is a two-phase short-circuit accident, an accident at the time of a short-circuit accident Overcurrent according to the range specified operation time characteristic, proportional operation time characteristic or multistage operation time characteristic based on the value obtained by dividing the current amplitude value by 3 ^1/2 / 2 or the value obtained by multiplying the tap magnification by 3 ^1/2 / 2. This was achieved by determining the operating time limit of the relay device.

Embodiments of the overcurrent relay device of the present invention will be described below with reference to the drawings.
An overcurrent relay device (not shown) according to an embodiment of the present invention generates a trip signal for interrupting each phase breaker (not shown) installed in the red phase, white phase and blue phase of a transmission line. A trip signal generating circuit 10 shown in FIG. 1 is provided as a trip signal generating circuit for achieving the above.

The trip signal generation circuit 10 includes _first to _third amplitude value calculation units 11 _{1 to} 11 ₃ , _first to _third time limit element operation determination units 12 _{1 to} 12 _3, and _first to _third time limit processes. Units 13 _{1 to} 13 ₃ , first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ , an accident aspect determination unit 15, and first and second OR circuits 16 ₁ and 16 _2. .

The first to third amplitude value calculators 11 _{1 to} 11 ₃ perform analog processing after extracting only frequency components in a necessary band by an input filter (not shown) included in the overcurrent relay device according to this embodiment. / Amplitude values of red phase fault current data I _R , white phase fault current data I _W and blue phase fault current data I _B converted from analog current to digital current by a digital conversion unit (not shown) are obtained.

When the first to third time-limit element operation determination units 12 _{1 to} 12 ₃ receive a high-level accident mode determination result signal (indicating that a three-phase short-circuit accident has occurred) from the accident mode determination unit 15, the red phase Then, it is determined whether the amplitude values of the white phase and blue phase fault current data I _R , I _W , I _B are equal to or greater than the settling time tap value. As a result, if it is determined that “the amplitude values of the red phase, white phase, and blue phase fault current data I _R , I _W , and I _B are greater than or equal to the settling time limit tap value”, the first to third time element operation determining units 12 _{1 to} 12 ₃ send the high level output signal and the amplitude values of the red, white and blue phase fault current data I _R , I _W and I _B to the first to third time processing units 13 _{1 to} 13 ₃ , respectively. Output each.
On the other hand, when the first to third time-limit element operation determination units 12 _{1 to} 12 ₃ receive a low-level accident mode determination result signal (indicating the occurrence of a two-phase short-circuit fault) from the accident mode determination unit 15, A value obtained by dividing the amplitude value of the phase, white phase, and blue phase accident current data I _R , I _W , I _B by about 0.866 (hereinafter referred to as “amplitude conversion value”) and calculating the calculated red phase Then, it is determined whether or not the amplitude converted values of the white phase and blue phase fault current data I _R , I _W , and I _B are equal to or larger than the settling time tap value. As a result, if it is determined that “the amplitude converted values of the red, white, and blue phase fault current data I _R , I _W , and I _B are equal to or larger than the settling time limit tap value”, the first to third time element operation determining units Reference numerals 12 _{1 to} 12 ₃ denote high-level output signals and amplitude-converted values of red phase, white phase, and blue phase fault current data I _R , I _W , and I _B as first to third time processing units 13 _{1 to} 13, respectively. Output to ₃ respectively.

The first to third time limit processing units 13 _{1 to} 13 ₃ receive the high-level output signals from the _first to _third time limit element operation determination units 12 _{1 to} 12 ₃ and receive the _first to _third time processing units. According to the range-designated operation time characteristic curve a using the amplitude value or the amplitude converted value of the red, white and blue phase fault current data I _R , I _W , I _B input from the time element operation determination units 12 _{1 to} 12 _3. An operation time period is obtained, and first to third time element trip signals T1 _R , T1 _W , T1 _B for breaking each phase breaker after the elapse of the obtained operation time period are output.

Here, the range specifying operation time characteristic curve a is different from the operation time characteristic curve A shown in FIG. 8B in the following points.
(1) As shown in FIG. 2, the operation time characteristic in the time element operation range of the range designation operation time characteristic curve a is the first time limit characteristic whose operation time is constant according to the total impedance% Z, and the total impedance%. It is defined by a combination of a proportional time characteristic in which the operation time period increases in proportion to Z and a second fixed time characteristic in which the operation time period is constant by the total impedance% Z.
(2) The operation time limit in the first fixed time characteristic is set to be smaller than the operation time limit in the operation time characteristic curve A.
(3) The proportional coefficient of the proportional time characteristic is a value obtained by dividing the difference between the time limit of the coordination point and the time limit of the IT limit point by the difference between the magnification of the cooperation point and the magnification of the IT limit point, or the time limit of the cooperation point The difference between the time limit at the IT limit point and the amplitude value of the accident current at the coordination point and the amplitude value of the accident current at the IT limit point is divided by the difference.
(4) The operation time limit in the second fixed time characteristic is made smaller than the operation time limit in the operation time characteristic curve A.
By using such a range specification operation time characteristic curve a, it is possible to shorten the operation time period of the overcurrent relay device as a whole, except for the coordination point, as compared to the case of using the operation time characteristic curve A. it can.
In addition, by using the range designation operation time characteristic curve b shown in FIG. 2 instead of the operation time characteristic curve B shown in FIG. Even when the relay device (for example, the second overcurrent relay device 110 ₂ shown in FIG. 8A) does not operate as shown by the black cross in FIG. 2, the overcurrent relay device ( For example, the first overcurrent relay device 110 ₁ ) shown in FIG. 8A operates in a short operation time period (about 0.7 s) as shown by a black circle in FIG. Can be improved.

The first to third instantaneous element motion determination units 14 _{1 to} 14 ₃ receive the high-level accident mode determination result signal (indicating the occurrence of a three-phase short-circuit accident) from the accident mode determination unit 15 and receive the first. to third amplitude value calculating unit 11 ₁ to 11 ₃ red phase inputted from the white phase and Aosho fault current data I _R, I _W, whether the amplitude value of I _B is settling instantaneous tap values higher Judge each one. As a result, if it is determined that “the amplitude values of the red, white, and blue phase fault current data I _R , I _W , and I _B are equal to or greater than the settling instantaneous tap value”, the first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ respectively output first to third instantaneous element trip signals T2 _R , T2 _W , and T2 _B for instantaneously interrupting each phase circuit breaker.
On the other hand, when the first to third instantaneous element motion determination units 14 _{1 to} 14 receive a low-level accident mode determination result signal (indicating the occurrence of a two-phase short circuit accident) from the accident mode determination unit 15, the red phase , White phase and blue phase accident current data I _R , I _W , I _B Amplitude conversion value (Amplitude value divided by about 0.866), and calculated red phase, white phase and blue phase accident current data It is determined whether or not the amplitude converted values of I _R , I _W , and I _B are greater than or equal to the settling instantaneous tap value. As a result, if it is determined that “the amplitude converted values of the red, white, and blue phase fault current data I _R , I _W , and I _B are greater than or equal to the settling instantaneous tap value”, the first to third instantaneous element operation determination units Reference numerals 14 _{1 to} 14 ₃ respectively output first to third instantaneous element trip signals T2 _R , T2 _W , and T2 _B for instantaneously interrupting each phase breaker.

Accident aspects determination unit 15, first to third amplitude value calculating unit 11 ₁ to 11 ₃ red phase inputted from the white phase and Aosho fault current data I _R, I _W, based on the amplitude value of I _B Then, it is determined whether the accident aspect is a three-phase short-circuit accident or a two-phase short-circuit accident. As a result, when it is determined that “the accident aspect is a three-phase short-circuit accident”, the accident aspect determination unit 15 outputs a high-level accident aspect determination result signal. On the other hand, if it is determined that “the accident aspect is a two-phase short-circuit accident”, the accident aspect determination unit 15 outputs a low-level accident aspect determination result signal.
At this time, the accident aspect determination unit 15 determines that the amplitude values of the red-phase, white-phase, and blue-phase accident current data I _R , I _W , and I _B are all greater than a predetermined threshold value (may be a settling time limit tap value). It is determined that “the accident aspect is a three-phase short-circuit accident”, and otherwise, it is determined that “the accident aspect is a two-phase short-circuit accident”.

The first logical sum circuit 16 ₁ calculates the logical sum of the first to third time-limit element trip signals T1 _R , T1 _W , T1 _B input from the first to _third time-limit processing units 13 _{1 to} 133. As a result, a first trip signal T1 is generated for shutting off the phase breakers at once after the operation time limit elapses.
The second OR circuit 16 _2, first to third instantaneous element trip signal T2 _R input from the first through third instantaneous element operation judging unit 14 ₁ to 14 _3, T2 _W, T2 logic _B By taking the sum, a second trip signal T2 for instantaneously shutting off the phase breakers at once is generated.

Next, the operation of the first and second overcurrent relay devices 50 ₁ and 50 ₂ that are the overcurrent relay devices according to the present embodiment when a short circuit accident occurs in the power system shown in FIG. Will be described with reference to FIGS.

First, the operation of the first and second overcurrent relay devices 50 ₁ and 50 ₂ when the short-circuit accident that has occurred is a three-phase short-circuit accident will be described with reference to the flowchart shown in FIG.
As shown in FIG. 3A, when a three-phase short circuit accident occurs behind the second overcurrent relay device 50 _{2, the} fault current I having an amplitude value larger than a predetermined threshold is a red phase of the transmission line, It flows into the white phase and the blue phase, respectively. This fault current I is supplied to the first and second overcurrent relay devices 50 ₁ , 50 ₁ through the first and second current transformers 3 ₁ , 3 ₂ (installed for each phase of the transmission line). 50 ₂ , only the frequency component of the necessary band is extracted by the input filter, and further converted from the analog current to the digital current by the analog / digital conversion unit, whereby red phase, white phase and blue phase accident current data I Conversion into _R , I _W , and I _B is performed (step S11).

In the first and second overcurrent relay devices 50 ₁ and 50 ₂ , the _first to _third amplitude value calculators 11 _{1 to} 11 _{3 of} the trip signal generation circuit 10 are connected to the red phase, white phase, and blue phase accident currents. The amplitude values of the data I _R , I _W , and I _B are obtained (step S12).

Moreover, the accident element determination unit 15, first to third amplitude value calculating unit 11 ₁ to 11 ₃ red phase inputted from the white phase and Aosho fault current data I _R, I _W, the amplitude value of I _B is Since all are larger than the predetermined threshold, it is determined that “the accident aspect is a three-phase short-circuit accident” and a high-level accident aspect determination result signal is output (step S13).

In the second overcurrent relay device 50 ₂ , the first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ receive a high-level accident mode determination result signal from the accident mode determination unit 15 (a three-phase short-circuit accident occurs). are shown.) is input, first to third amplitude value calculating unit 11 ₁ to 11 ₃ red phase inputted from the white phase and Aosho fault current data I _R, I _W, the amplitude value of I _B Is determined to be greater than or equal to the settling instantaneous tap value. As a result, for example, red phase, white phase and Aosho fault current data I _R, I _W, the amplitude value of I _B is a 30A, red phase, white phase and Aosho fault current data I _R, I _W, the I _B Since the amplitude value is equal to or larger than the settling instantaneous tap value (see the white circle in FIG. 3B), the first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ receive the first to third instantaneous element trip signals. T2 _R , T2 _W , and T2 _B are output (step S14).
As a result, the high-level second trip signal T2 is output from the second OR circuit 16 ₂ to the second circuit breaker 4 ₂ (installed for each phase of the transmission line), and the second trip signal T2 is output. Circuit breaker 4 ₂ is shut off instantaneously.

In the first overcurrent relay device 50 ₁ , the first to third time-limit element operation determination units 12 _{1 to} 12 ₃ receive a high-level accident mode determination result signal (three-phase short circuit) from the accident mode determination unit 15. Is input), the red, white and blue phase accident current data I _R , I _W , I _B input from the _first to _third amplitude value calculators 11 _{1 to} 11 ₃ are input. It is determined whether the amplitude value is equal to or greater than the settling time tap value. As a result, the first to third time element operation determination units 12 _{1 to} 12 ₃ indicate that “the amplitude values of the red phase, white phase, and blue phase fault current data I _R , I _W , I _B are equal to or greater than the settling time limit tap value. The first to third time processing units 13 _{1 to} 13 ₃ determine the high-level output signal and the red, white and blue phase fault current data I _R , I _W and I _B as amplitude values. (Step S15).

The first to third time limit processing units 13 _{1 to} 13 ₃ receive the high-level output signals from the _first to _third time limit element operation determination units 12 _{1 to} 12 ₃ and receive the _first to _third time processing units. red phase input from time limit element operation judging unit 12 ₁ to 12 _3, the white phase and Aosho fault current data I _R, I _W, I range designation operation time characteristics shown in FIG. 3 (b) based on the amplitude value of _B After the operation time period determined according to the curve a has elapsed, the first to third time element trip signals T1 _R , T1 _W , T1 _B are output (step S16).
Thus, a first trip signal T1 of a high level (which is installed on each phase of the transmission line.) The first OR circuit 16 ₁ first breaker 4 ₁ to be outputted, the first breaker 4 ₁ is interrupted after the operation timed lapse.

Next, the flowchart shown in FIG. 5 shows the operation of the first and second overcurrent relay devices 50 ₁ and 50 ₂ when the short-circuit accident that has occurred is a two-phase short-circuit accident between the red phase and the white phase. Will be described with reference to FIG.
When a two-phase short-circuit accident between the red phase and the white phase occurs behind the second overcurrent relay device 50 ₂ , the fault current I having an amplitude value larger than a predetermined threshold value is applied to the red phase and the white phase of the transmission line, respectively. Flowing. The fault currents I flowing in the red phase, white phase and blue phase of the transmission line are respectively supplied to the first and second overcurrent relay devices 50 ₁ and 50 via the first and _second current transformers 3 ₁ and 3 _{2. 2} and only the frequency component of the required band is extracted by the input filter, and further converted from the analog current value to the digital current value by the analog / digital conversion unit, so that the red, white and blue phase accident current data Converted to I _R , I _W , I _B (step S21).

In the first and second overcurrent relay devices 50 ₁ and 50 ₂ , the _first to _third amplitude value calculators 11 _{1 to} 11 _{3 of} the trip signal generation circuit 10 are connected to the red phase, white phase, and blue phase accident currents. The amplitude values of the data I _R , I _W , and I _B are obtained (step S22).

Moreover, the accident element determination unit 15, first to third amplitude value calculating unit 11 ₁ to 11 ₃ red phase inputted from the white phase and Aosho fault current data I _R, I _W, the amplitude value of I _B Since only the amplitude values of the red and white phase accident current data I _R and I _W are larger than the predetermined threshold, it is determined that “the accident mode is a two-phase short-circuit fault” and the low-level accident mode determination result signal is Output (step S23).

In the second overcurrent relay device 50 ₂ , the first and second instantaneous element operation determination units 14 ₁ , 14 ₂ receive a low-level accident mode determination result signal (a two-phase short-circuit accident occurrence) from the accident mode determination unit 15. Is input), the amplitude values of the red and white phase fault current data I _R and I _W input from the first and second amplitude value calculation units 11 ₁ and 11 ₂ are divided by about 0.866. red phase and Te Shirosho fault current data I _R, calculates the amplitude corresponding value of I _W, calculated red phase and Shirosho fault current data I _R, whether amplitude corresponding value of I _W is settling instantaneous tap values higher Determine. As a result, for example, as shown in FIG. 3B, even if the amplitude values of the red-phase and white-phase accident current data I _R , I _W are 26 A, the first and second instantaneous element operation determination units 14 ₁ , 14 ₂ is calculated by dividing 26A indicated by a white arrow in FIG. 2B by about 0.866 to calculate the amplitude conversion value = 30A of the red and white phase accident current data I _R and I _W , It is determined that the amplitude converted values of the current data I _R and I _W are equal to or larger than the settling instantaneous tap value, and the first and second instantaneous element trip signals T2 _R and T2 _W are output (step S24).
Thus, the second trip signal T2 of high level is output from the second OR circuit 16 ₂ in the second circuit breaker 4 _2, the second circuit breaker 4 ₂ is cut off instantly.

Further, in the first overcurrent relay device 50 ₁ , the first and second time-limit element operation determination units 12 ₁ and 12 ₂ receive a low-level accident mode determination result signal (two-phase short circuit fault) from the accident mode determination unit 15. Is input), the amplitude values of the red and white phase fault current data I _R and I _W input from the first and second amplitude value calculation units 11 ₁ and 11 ₂ are set to about 0.866. divided by calculated amplitude converted value of the red phase and Shirosho fault current data I _R, I _W, calculated red phase and Shirosho fault current data I _R, or amplitude corresponding value of I _W is not less than the tap value when SeiJogen Determine whether or not. As a result, for example, as shown in FIG. 3B, even if the amplitude values of the red-phase and white-phase fault current data I _R , I _W are 26 A, the first and second time limit element operation determination units 12 ₁ , 12 ₂ is calculated by dividing 26A indicated by a white arrow in FIG. 2B by about 0.866 to calculate the amplitude conversion value = 30A of the red and white phase accident current data I _R and I _W , It is determined that the amplitude converted values of the current data I _R and I _W are equal to or larger than the settling time limit tap value, and a high level output signal is output to the first and second time processing units 13 ₁ and 13 ₂ , respectively ( Step S25).

When the first and second time limit processing units 13 ₁ and 13 ₂ receive high level output signals from the first and second time limit element operation determination units 12 ₁ and 12 ₂ , the first and _second time limit processing units 13 ₁ and 13 ₂ Based on the amplitude-converted values of the red-phase and white-phase fault current data I _R , I _W input from the time-limit element operation determination units 12 ₁ , 12 ₂ , it was obtained according to the range-designated operation time-limit characteristic curve a shown in FIG. After the elapse of the operation time period, the first and second time element trip signals T1 _R and T1 _W are output (step S26).
Thus, a first trip signal T1 of the high level is output from the first OR circuit 16 ₁ to the first breaker 4 _1, the first breaker 4 ₁ is interrupted after the operation timed lapse.

  Note that the use of the overcurrent relay device according to the present embodiment instead of the overcurrent relay device 220 shown in FIG. 9A prevents the two-stage operation region of the short-circuit distance relay device from being narrowed. In addition, it is possible to prevent the short-circuit distance relay device from performing far-end protection when the overcurrent relay device is not operating in the three-stage operation region.

In the above description, the first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ and the first to third time limit element operation determination units 12 _{1 to} 12 ₃ use the amplitude of the accident current at the time of the two-phase short circuit accident. By dividing the value by 3 ^1/2 / 2, the amplitude value of the accident current at the time of the two-phase short circuit accident was converted into the amplitude value of the accident current at the time of the three-phase short circuit accident. By multiplying the value by 3 ^1/2 / 2, the amplitude value of the accident current at the time of the three-phase short circuit accident may be converted into the amplitude value of the accident current at the time of the two-phase short circuit accident. In this case, instead of the range-specified operation time characteristic curve that determines the operation time limit of the overcurrent relay device based on the amplitude value of the accident current at the time of the three-phase short circuit accident, A range-designated operation time characteristic curve that determines the operation time limit of the overcurrent relay device based on the amplitude value is used.

In the first to third time processing units 13 _{1 to} 13 ₃ , the operation time limit is obtained by using the range designation operation time characteristic curve a. However, the proportional operation time characteristic curve m shown in FIG. 6 or FIG. The operation time limit may be obtained using the multistage operation time characteristic curve p.

Here, the proportional operation time characteristic curve m is different from the operation time characteristic curve A shown in FIG. 8B in the following points.
(1) The operation time characteristic in the time element operating range of the proportional operation time characteristic curve m is defined by a proportional time characteristic in which the operation time increases in proportion to the total impedance% Z, as shown in FIG.
(2) The operation time period in the proportional time characteristic is set to be smaller than the operation time period in the operation time characteristic curve A except for the coordination point.
(3) The proportionality coefficient is a value obtained by dividing the difference between the time limit of the coordination point and the time limit of the IT limit point by the difference between the magnification of the coordination point and the magnification of the IT limit point, or the time limit of the coordination point and the IT limit point The difference from the time is divided by the difference between the fault current amplitude value at the coordination point and the fault current amplitude value at the IT limit point.
By using such a proportional operation time characteristic curve m, the operation time period of the overcurrent relay device can be shortened as a whole, except for the coordination point, as compared with the case where the operation time characteristic curve A is used. .
Further, by using the proportional operation time characteristic curve n shown in FIG. 6 in place of the operation time characteristic curve B shown in FIG. Even when the electric device (for example, the second overcurrent relay device 110 ₂ shown in FIG. 8A) does not operate as indicated by the black cross in FIG. 6, the overcurrent relay device on the power source side (for example, Since the first overcurrent relay device 110 ₁ ) shown in FIG. 8A operates in a short operation time (about 1.5 s) as shown by a black circle in FIG. 6, the protection reliability of the transmission line is improved. Can be made.

The multistage operation time characteristic curve p is different from the operation time characteristic curve A shown in FIG.
(1) The operation time characteristic in the time element operation range of the multistage operation time characteristic curve p is defined by a combination of a plurality of operation time characteristics, such as the combination of the strong anti-time characteristic and the normal anti-time characteristic shown in FIG. The
(2) In the back-up protective relay device instantaneous elements operating range (FIG. 8 (b) second overcurrent relay device 110 ₂ etc.), the operation time characteristics of the time limit elements operating range of the multi-stage operation time characteristics curve p In the example shown in FIG. 7, the strong time limit characteristic is such that the operation time period is smaller than the operation time characteristic curve A (the normal time limit characteristic in the example shown in FIG. 7).
In addition, when the multistage operation time characteristic curve q shown in FIG. 7 is used instead of the operation time characteristic curve B shown in FIG. 8B, the operation time characteristic curve in which the time limit element operation range is all defined as, for example, a strong reaction time characteristic. The necessary protection range in the time limit element operation range can be ensured as compared with the case of using.

  Furthermore, although the operation time characteristic curve that determines the operation time limit of the overcurrent relay device based on the amplitude value of the accident current at the time of the three-phase short circuit accident is used, the operation time limit of the overcurrent relay device is determined based on the tap magnification. When using the operating time characteristic curve, the settling tap value at the time of the three-phase short-circuit accident is converted into the settling tap value at the time of the two-phase short-circuit accident or the two-phase short-circuit according to the determination result in the accident mode determination unit 15 The settling tap value at the time of the accident is converted into the settling tap value at the time of the three-phase short-circuit accident, and the tap current is calculated by dividing the amplitude value of the accident current at the time of the short-circuit accident by the converted settling tap value. The operation time limit of the overcurrent relay device may be obtained according to the operation time characteristic curve based on the magnification.

That is, when using the operation time characteristic that determines the operation time limit of the overcurrent relay device based on the tap magnification at the time of the three-phase short-circuit accident, the first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ When a low-level accident mode determination result signal (indicating the occurrence of a two-phase short-circuit fault) is input from the accident mode determination unit 15, instead of calculating the amplitude-converted values of the red-phase and white-phase fault current data I _R and I _W Using the settling instantaneous tap converted value obtained by multiplying the settling instantaneous tap value by 3 ^1/2 / 2, the amplitude value of the red and white phase accident current data I _R and I _W is divided by the settling instantaneous tap converted value to obtain the tap magnification. And the first and second instantaneous element trip signals T2 _R and T2 _W are output according to the calculated time-dependent characteristic curve based on the tap magnification.
Similarly, the first to third time-limit element operation determination units 12 _{1 to} 12 ₃ receive a low-level accident mode determination result signal (indicating the occurrence of a two-phase short circuit accident) from the accident mode determination unit 15. Instead of calculating the red-phase and white-phase accident current data I _R and I _W , the red-phase and white-phase accident currents are calculated using the settling time-tap converted value obtained by multiplying the settling time-tap value by 3 ^1/2 / 2. When it is determined whether the amplitude values of the data I _R and I _W are equal to or greater than the settling time tap conversion value, and the red and white phase fault current data I _R and I _W are greater than the settling time tap conversion value A high level output signal is output to the first and second time processing units 13 ₁ and 13 ₂ . At this time, the first and second time limit processing units 13 ₁ and 13 ₂ receive the red and white phase fault current data I _R and I input from the first and second time limit element operation determination units 12 ₁ and 12 _{2. The} tap magnification is calculated by dividing the amplitude value of _W by the settled time limit tap conversion value input from the first and second time limit element motion determination units 12 ₁ and 12 ₂ , and the operation time characteristic curve is calculated based on the calculated tap magnification. After the elapse of the operation time period obtained from the above, the first and second time element trip signals T1 _R and T1 _W are output, respectively.

In addition, when using the operation time characteristic that determines the operation time period of the overcurrent relay device based on the tap magnification at the time of the two-phase short circuit accident, the first to third instantaneous element operation determination units 14 _{1 to} 14 ₃ are When a high-level accident mode determination result signal (indicating the occurrence of a three-phase short-circuit accident) is input from the accident mode determination unit 15, the red, white and blue phase accident current data I _R , I _W , I _B using settling instantaneous tap converted value obtained by dividing the settling instantaneous tap values at 3 ^1/2 / 2 instead of calculating the amplitude conversion value, the red phase, the white phase and Aosho fault current data I _R, I _W, the I _B The tap magnification is calculated by dividing the amplitude value by the settling instantaneous tap conversion value, and the first to third instantaneous element trip signals T2 _R , T2 _W , T2 _B are output according to the operation time characteristic curve based on the calculated tap magnification. To do.
Similarly, when the first to third time-limit element operation determination units 12 _{1 to} 12 ₃ receive a high-level accident mode determination result signal (indicating that a three-phase short circuit accident has occurred) from the accident mode determination unit 15. Instead of calculating the amplitude converted values of red phase, white phase and blue accident current data I _R , I _W , I _B , use the settling time tap converted value obtained by dividing the settling time tap value by 3 ^1/2 / 2, It is determined whether the red, white, and blue phase fault current data I _R , I _W , and I _B are greater than the settling time tap converted value, and the red, white, and blue phase fault current data I _R , When the amplitude values of I _W and I _B are equal to or greater than the settling time tap conversion value, a high level output signal is output to the first to third time processing units 13 _{1 to} 13 ₃ . At this time, the first to third time limit processing units 13 _{1 to} 13 ₃ receive the red phase, white phase, and blue phase accident current data I input from the _first to _third time limit element operation determination units 12 _{1 to} 12 _{3. R,} I _W, divided by SeiJogen tap converted value of the amplitude value is input from the first through third time limit element operation judging unit 12 ₁ to 12 ₃ I _B calculates the tap factor, the calculated tap factor Based on the operation time characteristic curve obtained based on the operation time characteristic curve, the first to third time element trip signals T1 _R , T1 _W and T1 _B are output.

Furthermore, the trip signal generation circuit 10 includes the first to third time limit element operation determination units 12 _{1 to} 12 ₃ instead of the accident aspect determination unit 15, and the _first to _third time limit element operation determination units 12. _When all the output signals _{1 to} 12 ₃ are at a high level, the above-described processing is performed as “the accident aspect is a three-phase short-circuit accident”, while the first to third time-limit element operation determination units 12 are performed. _When any one of the output signals _{1 to} 12 ₃ is at a low level, the above-described processing may be performed assuming that the accident aspect is a two-phase short-circuit accident. The same applies to the _{first to} third instantaneous element motion determination units 14 _{1 to} 14 ₃ .

Furthermore, although the trip signal generation circuit 10 includes the accident aspect determination unit 15, the accident aspect determination unit 15 may be omitted. Even in this case, the first to third time processing units 13 _{1 to} 13 ₃ perform the range designation operation time characteristic a based on the amplitude values of the red phase, white phase, and blue phase fault current data I _R , I _W , I _B. , B, proportional operation time characteristics m, n or multistage operation time characteristics p, q, by determining the operation time of the overcurrent relay devices 50 ₁ , 50 ₂ , when using the conventional operation time characteristics A, B In comparison, the operation time limit of the overcurrent relay devices 50 ₁ and 50 ₂ can be shortened.

1 is a block diagram illustrating a configuration of a trip signal generation circuit 10 included in an overcurrent relay device according to an embodiment of the present invention. It is a diagram for explaining range designation operation time characteristics curve a used in the first to third timed processor _{131-134 3} shown in FIG. It is a diagram for explaining the first and second overcurrent relay device 50 _1, 50 ₂ of the operation when the short circuit in the transmission line occurs in the power system. 4 is a flowchart for explaining the operation of first and second overcurrent relay devices 50 ₁ and 50 ₂ when a three-phase short-circuit accident occurs in the power system shown in FIG. 4 is a flowchart for explaining the operation of the first and second overcurrent relay devices 50 ₁ and 50 ₂ when a two-phase short circuit accident occurs in the power system shown in FIG. It is a figure for demonstrating the proportional operation time characteristic curve m which can be used instead of the range designation | designated operation time characteristic curve a shown in FIG. It is a figure for demonstrating the multistage operation | movement time characteristic curve p which can be used instead of the range designation | designated operation | movement time characteristic curve a shown in FIG. It is a figure for demonstrating that an operation time limit becomes late at the time of a two-phase short circuit accident in the conventional overcurrent relay apparatus. It is a figure for demonstrating that an operation time limit becomes late at the time of a two-phase short circuit accident in the conventional overcurrent relay apparatus.

DESCRIPTION OF SYMBOLS 1 Power supply 3 ₁ , 3 ₂ 1st and 2nd current transformer 4 ₁ , 4 ₂ 1st and 2nd circuit breaker 10 Trip signal generation circuit 11 1-11 _{3 1st} thru | or 3rd amplitude value calculating part 12 ₁ to _{3 1st} to _3rd time-limit element operation determination unit 13 _{1 to 1 3} 1st to 3rd time processing unit 14 _{1 to} 14 ₃ 1st to 3rd instantaneous element operation determination unit 15 Accident aspect determination unit 16 ₁ , 16 ₂ First and second OR circuits 110 ₁ , 110 ₂ First and second overcurrent relay devices 210 Short-circuit distance relay device 220 Overcurrent relay devices A, B, A ′, B ', C, D, C', D 'Operation time characteristic curve a, b Range specification operation time characteristic curve m, n Proportional operation time characteristic curve p, q Multi-stage operation time characteristic curve I Fault current I _R , I _W , I _B red phase, white phase and Aosho fault current data T1 _R, T1 _W, T1 _B first through third time limiting element trip signal T2 _R T2 _W, T2 _B first to third instantaneous element trip signals T1, T2 the first and second trip signal S11 to S16, S21 to S26 step

Claims (15)

An overcurrent relay device used for protection in the event of a short circuit accident of a transmission line in an electric power system,
Comprising an operation time period determining means for determining an operation time period of the overcurrent relay device according to an operation time period characteristic that determines an operation time period of the overcurrent relay device based on an amplitude value of an accident current at the time of a short circuit accident;
The operation time characteristic is a range specification operation time characteristic,
The operation time characteristic in the instantaneous element operation range of the range specification operation time characteristic is defined by the fixed time characteristic,
The time limit element of the range specified operation time characteristic is the first time limit characteristic in which the operation time period is constant by the total impedance from the power source (1), and the operation time period increases in proportion to the total impedance. Defined by a combination of a proportional time-delay characteristic and a second time-delay characteristic whose operating time is constant by the total impedance,
An overcurrent relay device. An overcurrent relay device used for protection in the event of a short circuit accident of a transmission line in an electric power system,
Comprising an operation time period determining means for determining an operation time period of the overcurrent relay device according to an operation time period characteristic that determines an operation time period of the overcurrent relay device based on an amplitude value of an accident current at the time of a short circuit accident;
The operation time characteristic is a proportional operation time characteristic,
The operation time characteristic in the instantaneous element operation range of the proportional operation time characteristic is defined by the fixed time characteristic,
The operation time characteristic in the time element operation range of the proportional operation time characteristic is defined by a proportional time characteristic in which the operation time period increases in proportion to the total impedance from the power source (1).
An overcurrent relay device. An overcurrent relay device used for protection in the event of a short circuit accident of a transmission line in an electric power system,
Comprising an operation time period determining means for determining an operation time period of the overcurrent relay device according to an operation time period characteristic that determines an operation time period of the overcurrent relay device based on an amplitude value of an accident current at the time of a short circuit accident;
The operation time characteristic is a multi-stage operation time characteristic,
The operation time characteristic in the instantaneous element operation range of the multi-stage operation time characteristic is defined by the fixed time characteristic,
The operation time characteristic in the time limit element operation range of the multistage operation time characteristic is defined by a combination of a plurality of operation time characteristics.
An overcurrent relay device. An overcurrent relay device (50 ₁ , 50 ₂ ) used for protection in the event of a short circuit accident of a transmission line in an electric power system,
Range-specified operation time-limit characteristics, proportional operation time-limit characteristics, or multistage operation that determines the operation time limit of the overcurrent relay device based on the amplitude value of the accident current at the time of a three-phase short circuit accident or the amplitude value of the accident current at the time of a two-phase short circuit An operation time period determining means (12 _{1 to} 12 ₃ , 13 _{1 to} 13 ₃ , 14 _{1 to} 14 ₃ ) for determining the operation time period of the overcurrent relay device according to the time characteristic;
An accident mode judging means (15) for judging whether a three-phase short-circuit accident or a two-phase short-circuit accident,
The operation time determining means converts the amplitude value of the accident current at the time of the two-phase short-circuit accident into the amplitude value of the accident current at the time of the three-phase short-circuit accident or the three-phase short-circuit accident according to the determination result in the accident aspect determination means The amplitude value of the accident current at the time is converted into the amplitude value of the accident current at the time of the two-phase short circuit accident, and the range-designated operation time characteristic, the proportional operation time characteristic, or the multi-stage based on the converted amplitude value of the accident current Obtain the operating time limit of the overcurrent relay device according to the operating time characteristics.
An overcurrent relay device. The operation time characteristic in the instantaneous element operation range of the range specification operation time characteristic is defined by the fixed time characteristic, and the operation time characteristic in the time element operation range of the range specification operation time characteristic is the total impedance from the power source (1). Stipulated by a combination of a first fixed time characteristic in which the operation time is constant, a proportional time characteristic in which the operation time increases in proportion to the total impedance, and a second fixed time characteristic in which the operation time is constant by the total impedance And
The operation time characteristic in the instantaneous element operation range of the proportional operation time characteristic is defined by the fixed time characteristic, and the operation time characteristic in the time element operation range of the proportional operation time characteristic is proportional to the total impedance. Defined by an increasing proportional time-delay characteristic,
The operation time characteristic in the instantaneous element operation range of the multi-stage operation time characteristic is defined by a fixed time characteristic, and the operation time characteristic in the time element operation range of the multi-stage operation time characteristic is defined by a combination of a plurality of operation time characteristics. The
The overcurrent relay device according to claim 4, wherein: The operation time determining means divides the amplitude value of the accident current at the time of the two-phase short-circuit accident by 3 ^1/2 / 2, and thereby the amplitude value of the accident current at the time of the two-phase short-circuit accident is calculated as the accident current at the time of the three-phase short-circuit accident. The overcurrent relay device according to claim 4, wherein the overcurrent relay device is converted into an amplitude value. The operation time determining means multiplies the amplitude value of the accident current at the time of the three-phase short-circuit accident by 3 ^1/2 / 2, thereby obtaining the accident current value at the time of the two-phase short-circuit accident. The overcurrent relay device according to claim 4, wherein the overcurrent relay device is converted into an amplitude value. The operation time determination means is
An amplitude value is determined Delayed element operation judging unit to or greater than the tap value when SeiJogen (12 ₁ to 12 ₃₎ of the accident current when the short circuit,
A time processing means (13 _{1 to} 13 ₃ ) for obtaining an operation time limit of the overcurrent relay device in accordance with the range specifying operation time characteristic, the proportional operation time characteristic or the multistage operation time characteristic;
When the determination result in the accident aspect determination means is a three-phase short-circuit accident, the time-limit element operation determination means determines whether or not the amplitude value of the accident current at the time of the short-circuit accident is greater than or equal to the settling time limit tap value. In addition, the time limit processing means may perform the overload according to the range-designated operation time characteristic, the proportional operation time characteristic, or the multistage operation time characteristic based on the amplitude value of the fault current input from the time element operation determination means. Find the operating time limit of the current relay,
When the determination result in the accident aspect determination means is a two-phase short-circuit accident, the time-limit element operation determination means determines whether or not the amplitude value of the accident current at the time of the short-circuit accident is greater than or equal to the settling time limit tap value. In addition, the time limit processing means may perform the overload according to the range-designated operation time characteristic, the proportional operation time characteristic, or the multistage operation time characteristic based on the amplitude value of the fault current input from the time element operation determination means. Obtain the operating time limit of the current relay device, calculate the converted value of the accident current, which is the value obtained by dividing the amplitude of the accident current at the time of the short-circuit accident by 3 ^1/2 / 2, and calculate the amplitude of the calculated accident current It is determined whether or not a converted value is greater than or equal to the settling time limit tap value, and the range designated operation time limit characteristic and the proportional operation based on the amplitude converted value of the fault current input from the time element operation determining means Time Request operation timed the overcurrent relay device in accordance with the characteristics or the multi-stage operation time characteristics,
The overcurrent relay device according to claim 5 or 6, characterized by the above. The operation timed determining means comprises a momentary element operation judging means (14 ₁ to 14 _3),
The instantaneous element operation determining means determines whether the amplitude value of the accident current at the time of the short-circuit accident is equal to or larger than the settling instantaneous tap value when the determination result in the accident aspect determining means is a three-phase short-circuit accident. And
When the determination result in the accident aspect determination unit is a two-phase short circuit accident, the instantaneous element operation determination unit is a value obtained by dividing the amplitude value of the accident current at the time of the short circuit accident by 3 ^1/2 / 2. Amplitude conversion value of the accident current is calculated, and it is determined whether the calculated amplitude conversion value of the accident current is equal to or greater than the settling instantaneous tap value.
The overcurrent relay device according to claim 8, wherein:   The accident mode determination means determines that a three-phase short-circuit accident occurs when all of the amplitude values of the accident currents flowing through the phases of the transmission line are greater than a predetermined threshold at the time of the short-circuit accident, and a two-phase short-circuit accident otherwise. The overcurrent relay device according to claim 4, wherein the overcurrent relay device is determined. An overcurrent relay device (50 ₁ , 50 ₂ ) used for protection in the event of a short circuit accident of a transmission line in an electric power system,
A trip signal generating circuit (10) for generating a trip signal for interrupting a circuit breaker installed in the power transmission line;
The trip signal generation circuit
An amplitude value calculation unit (11 _{1 to} 11 ₃ ) for obtaining an amplitude value of the fault current data (I _R , I _W , I _B ) converted from the fault current at the time of the short-circuit fault;
An accident aspect determination unit (15) for determining whether the accident aspect is a three-phase short-circuit accident or a two-phase short-circuit accident based on the amplitude value of the accident current data input from the amplitude value calculation unit;
When the accident aspect determination unit determines that “the short circuit accident is a three-phase short circuit accident”, it determines whether or not the amplitude value of the accident current data is equal to or greater than the settling time tap value, while the accident aspect determination unit Determines that “the short-circuit accident is a two-phase short-circuit accident”, the amplitude conversion value of the accident current data, which is a value obtained by dividing the amplitude value of the accident current data by 3 ^1/2 / 2, is calculated. A time limit element operation determination unit (12 _{1 to} 12 ₃ ) for determining whether or not an amplitude converted value of an accident current is equal to or greater than the settling time limit tap value;
In accordance with the output signal of the time element operation determination unit, the operation time limit of the overcurrent relay device is determined from the amplitude value of the fault current data input from the time element operation determination unit or the amplitude conversion value of the fault current. Time limit element trip signals (T1 _R , T1 _W , T1) for determining an operation time according to a specified range-specified operation time characteristic, proportional operation time characteristic or multistage operation time characteristic and breaking the breaker after the determined operation time elapses. _B ) and a time processing unit (13 _{1 to} 13 ₃ ) for outputting,
An overcurrent relay device. It said trip signal generating circuit further comprises a momentary element operation judging unit that outputs the instantaneous element trip signal for cutting off the circuit breaker instantaneously _{(T2 R, T2 W, T2} B) (14 1 ~14 3),
The instantaneous element operation determination unit determines whether or not the amplitude value of the accident current data is equal to or greater than a settling instantaneous tap value when the accident aspect determination unit determines that “the short circuit accident is a three-phase short circuit accident”. , When it is determined that “the amplitude value of the fault current data is equal to or greater than the settling instantaneous tap value”, the instantaneous element trip signal is output, while the accident mode determination unit indicates that “the short circuit accident is a two-phase short circuit accident”. When the determination is made, an amplitude conversion value of the accident current data, which is a value obtained by dividing the amplitude value of the accident current data by 3 ^1/2 / 2, is calculated, and the calculated amplitude conversion value of the accident current is not less than the settling instantaneous tap value. Whether or not, and when it is determined that "the converted amplitude value of the accident current data is equal to or greater than a settling instantaneous tap value", the instantaneous element trip signal is output.
The overcurrent relay device according to claim 11, wherein Based on the tap magnification at the time of a three-phase short-circuit accident or the tap magnification at the time of a two-phase short-circuit accident instead of the operation time-limit characteristic that determines the operation time limit of the overcurrent relay device based on the amplitude value of the accident current at the time of the short-circuit accident Using the operation time characteristic that determines the operation time of the overcurrent relay device,
The operation time determination means converts the settling tap value at the time of the three-phase short-circuit accident into the set-up tap value at the time of the two-phase short-circuit accident or the settling at the time of the two-phase short-circuit accident according to the determination result in the accident aspect determination means. The tap value is converted into a setting tap value at the time of a three-phase short circuit accident, and the tap magnification is calculated by dividing the amplitude value of the accident current at the time of the short circuit accident by the converted setting tap value. Based on the calculated tap magnification Obtaining an operation time limit of the overcurrent relay device according to the operation time characteristic;
The overcurrent relay device according to any one of claims 1 to 12, wherein the overcurrent relay device is characterized. The operation time determining means multiplies the setting tap value at the time of the three-phase short circuit accident by 3 ^1/2 / 2, thereby converting the setting tap value at the time of the three-phase short circuit accident into the setting tap value at the time of the two-phase short circuit accident. The overcurrent relay device according to claim 13, wherein The operation time determining means divides the setting tap value at the time of the two-phase short-circuit accident by 3 ^1/2 / 2 to convert the setting tap value at the time of the two-phase short-circuit accident into the setting tap value at the time of the three-phase short-circuit accident The overcurrent relay device according to claim 13, wherein