JPH10336882A - Distance relaying apparatus and distance relaying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct discrimination of an internal or external accident completely by fitting a transmission line trouble detection means and a bus trouble detection means, generating sum current and difference current with current data, and comparing the magnitude of the sum current with that of the difference current. SOLUTION: An inptu converter 36 on transmission line 1L side is connected with a current transformer 33B1, and the current value of phase current of the transmission line 1L outputted from the current transformer 33B1 is converted into available data with a calculating part 38. An input converter 37 on transmission line 2L side conducts conversion with the calculating part 38 in the same way. The calculating part 38 converts a phase current value IY into a line current value IΔ for each wire and adds line current values IΔ1 L, IΔ2 L for two wire to generate a sum current value and detect a bus 31 trouble. The sum current value and the difference current value for two wires are derived with phase current values IY1 L, IY2 L of respective wires to discriminate an internal trouble or an external trouble.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a distance relay device and a distance relay method capable of accurately selecting and interrupting an accident by measuring an impedance from a relay device installation point to an accident point by using current data and determining an operation time limit. Things,
In particular, using current and voltage data of two circuits taken together, it is possible to determine whether the current transformer has an accident in the direction of the transmission line or in the direction of the bus, perform accurate accident detection, and identify the accident section. The present invention relates to a two-circuit collective distance relay device with a direction discriminating element to be minimized.

[0002]

2. Description of the Related Art A distance relay device determines the distance to an accident point by extracting current and voltage of a transmission line by using a current transformer and a transformer and measuring the impedance of the transmission line. In addition, the selectivity of the accident point is higher than other relay devices, and high-speed protection is also possible. Therefore, even in the case of a large power transmission system and a complicated transmission line system, it is possible to perform an accurate selective cutoff for a failure.

FIG. 6 is a schematic diagram showing an accident occurrence system.
In the figure, 1 is a transmission line, 2A and 2B are power supplies, and 3 is a load. The power supplies 2A and 2B correspond to generators of a power plant, and the load 3 corresponds to equipment using electricity.
A and 2B generate a load 3
Supplied to 4A to 4D are circuit breakers at each substation, 5A to
5C is a current transformer for transforming the value of the current flowing through the transmission line 1 into a current value proportional to the current value. 6 is a busbar protection function (blockwise direction) for interrupting the circuit breaker 4C according to the current value of the current transformer 5C. Distance relay device (function to protect against accidents) (Fig. 6
Middle, indicated by 44). The current transformers 5A and 5B other than the current transformer 5C are each provided with a distance relay device. Reference numeral 7 denotes an accident point such as a short circuit accident of the transmission line 1. In FIG. 6, a transformer for transforming the voltage value of the transmission line 1 to a voltage value proportional thereto is omitted.

FIG. 7 is a logic circuit diagram showing an algorithm of a conventional distance relay device. FIG. 7 shows an algorithm of the distance relay device 6 of FIG. In the figure, reference numeral 10 denotes a first detecting unit for detecting an accident in a section (a section from the circuit breaker 4C to a position immediately before the circuit breaker 4A) of 80 to 90% of the total impedance of the section (a section from the circuit breaker 4C to the circuit breaker 4A). The step protection element (indicated by 44SX1 in FIG. 7), 11 is a section up to about 150% of the total impedance of the section (the circuit breaker 4).
A second-stage protection element (indicated by 44SX2 in FIG. 7) for detecting an accident in a section from C to a point corresponding to 150% of the total impedance of the own section after passing through the circuit breaker 4A, 1
Reference numeral 2 denotes a third-stage protection for detecting an accident in a section of 300 to 400% of the total impedance of the own section (a section corresponding to 300 to 400% of the total impedance of the own section after passing through the circuit breaker 4C from the breaker 4C). Elements (44S in FIG. 7)
I).

[0005] As described above, the operation time limit proportional to the distance to the accident point is set in the distance relay device. First
The step protection element 10 is 100% of the total impedance of the section.
Instead of being set to 80-90%, if it is set to 100% of the total impedance of the own section, it will actually be due to errors in relay equipment, errors in current transformers and transformers, and errors in calculation of transmission line impedance. In this case, the operation range may enter the next section, and a malfunction may occur due to an accident in the next section. Therefore, as shown in FIG. 6, the first-stage protection element 10 actually has a total impedance of 10 to 2
It is settled 0% shorter.

Reference numeral 13 denotes a blinder element (indicated by 44SIR in FIG. 7) which derives the impedance in the direction of the transmission line 1 from its own end (the installation point of the current transformer 5C) and judges an accident. A reactance element (indicated by 44SOX in FIG. 7) for deriving the reactance of the three directions (indicated by 44SOX in FIG. 7); Reference numeral 16 denotes a blinder element (44SOR in FIG. 7) which derives the impedance in the bus direction from its own end and determines an accident.
). The derivation of the impedance and reactance of these elements is based on the current transformer 5C provided on the transmission line 1 and the transmission line 1 taken out from the transformer (not shown).
The current value and the voltage value are used.

[0007] Of the above elements, the first stage protection element 1
0, the second-stage protection element 11, the third-stage protection element 12, and the blinder element 13 are elements for detecting an accident in the direction of the transmission line 1 (inward), while the reactance element 14,
The mo element 15 and the blinder element 16 are elements that detect an accident in the bus direction (outside direction). That is, the distance relay device 6 operates by detecting not only an accident in the direction of the transmission line 1 but also an accident in the direction of the bus.

Reference numerals 17 to 20 denote timed coordination timers (44ST1 to 44S in FIG. 7) for shifting (delaying) the operation time of each stage.
T4, hereinafter simply referred to as a timer).
The time to shift the operations of 7 to 20 is from the shorter timer 2
0, 17, 18, and 19 are set in this order. 21-2
5 is an AND gate and 26 is an OR gate.

Next, the operation will be described. When an accident of the transmission line 1 occurs at the accident point 7, a second-stage protection element (a second-stage protection element other than the distance relay device 6) that detects an accident in a section up to about 150% of the impedance of the own section operates. Before the operation, the elements 14 to 16 for detecting an accident in the direction of the bus operate to output a trip signal. This is because, since the time of the timer 20 is set to be the shortest, the elements 14 to 16 for detecting an accident in the bus direction operate quickly. The circuit breaker 4C is opened by this trip signal, and the power supply from the power sources 2A and 2B is stopped. Therefore, it is possible to separate the accident section at higher speed and to a minimum, thereby preventing the accident from spreading to a wide area.

Next, a case where the above distance relay device is applied to an accident occurrence system different from the system shown in FIG. 6 will be described. FIG. 8 is a schematic diagram showing an accident occurrence system different from that shown in FIG.
Is a load, 30 is a power supply, and 31 is a bus. The current of the power supply 30 is supplied to the load 3 via the transmission lines 1L and 2L and the bus 31. 32A1, 32A2, 32B1, and 32B2 are circuit breakers, and 33A1, 33A2, 33B1, and 33B2 are current transformers. Reference numeral 34 denotes a distance relay that operates according to the same algorithm as the distance relay 6 in FIG. The current transformer 33
Distance relays are also provided in the current transformers 33A1 and 33A2 other than B1 and 33B2. An accident point 35 is a point near the current transformer 33B1 of the transmission line 1L (closest point of the current transformer 33B1 in the direction of the transmission line (inward)). FIG. 6 omits a transformer for transforming the voltage value of the transmission line 1 to a voltage value proportional thereto.

Next, the operation will be described. When the load flow (current flowing in the direction of the load 3) of the system in FIG. 8 is equal to or greater than the minimum operating value (that is, when an excessive current flows through the transmission lines 1L and 2L and the possibility of an accident is high) )), When a short circuit accident occurs at the accident point 35, the current transformer 32B
The distance relay device 34 is determined by the current value (phase current value and line-to-line current value) and voltage value transformed by the 1, 32B2 (and the transformer).
Determines the accident. At this time, since the accident point 35 is an accident in the direction of the transmission line 1L, the first-stage protection element 10 for detecting the accident in the direction of the transmission line 1L should operate. However, in the case of an accident near the inside like the accident point 35, the reactance element 14 that detects an accident in the direction of the bus 31 operates due to an error between the two current transformers 33B1 and 33B2.
Since the time of the timer 20 is set to be the shortest, the reactance element 1 is activated before the first-stage protection element operates.
4 operates quickly and outputs a trip signal.

As a prior art related to the present invention, there is JP-A-59-149716.

[0013]

Since the conventional distance relay device is constructed as described above, it is provided with the elements 14 to 16 for detecting an accident in the direction of the bus 31. The accident in the direction of the bus 31 can be detected. In the case of an internal near-end accident at the three ends of the load, an error in the two current transformers 33B1 and 33B2 causes the bus 31
There is a problem that the elements 14 to 16 for detecting an accident in the direction are operated and erroneously determined to be an accident in the direction of the bus 31.

The present invention has been made in order to solve the above-mentioned problems. A sum current and a difference current are generated by using two-phase currents, and the magnitude of these sums is compared to determine whether an internal accident or an external accident has occurred. It is an object of the present invention to obtain a distance relay device and a distance relay method capable of reliably performing a determination.

[0015]

According to a first aspect of the present invention, there is provided a distance relay device, comprising: an arithmetic processing unit mounted in the distance relay device; In addition to the provision of the fault detection means, it is also configured to include the direction determination means for generating the sum current and the difference current using the current data, and comparing the sum current and the difference current to determine the direction of the fault point. Things.

According to a second aspect of the present invention, there is provided a distance relay device, wherein the arithmetic processing unit includes a transmission line direction accident detecting means, and further, a current conversion unit for converting current data of each line into line current data. A line sum current generation unit for adding line current data for each line from the current conversion unit to generate line sum current data; and adding and subtracting the current data for each line for phase summation. A phase current deriving unit that derives current data and phase difference current data, and a bus direction fault detection unit that detects a bus direction fault based on the line sum current data from the line sum current generation unit,
It is configured to include a direction discrimination processing unit that discriminates the direction of the fault point by comparing the sum of the phase sum current data and the phase difference current data from the phase current derivation unit.

According to a third aspect of the present invention, there is provided a distance relay device, wherein the arithmetic processing unit includes a transmission line direction accident detecting means, and further, a current conversion unit for converting current data of each line into line current data. And a line sum current generator for adding line current data for each line from the current converter to generate line sum current data; and a line current data for each line from the current converter. A line difference current generation unit that generates line difference current data by subtraction, a bus direction accident detection unit that detects a bus direction accident based on the line sum current data from the line sum current generation unit,
A direction discrimination processing unit for discriminating the direction of the fault point by comparing the magnitude of the line sum current data from the line sum current generator and the line difference current data from the line difference current generator; It was done.

According to a fourth aspect of the present invention, there is provided a distance relay device including a difference circuit for generating difference data by subtracting current data from a current transformer, and further comprising an arithmetic processing unit for detecting a transmission line direction accident detection. Means for converting line-by-line current data into line-to-line current data; and adding line-to-line current data from each of the lines from the current conversion unit to generate line-to-line sum current data. Current generator that performs line-to-line summation, a difference current converter that converts the difference data from the difference circuit into line-to-line difference data, and detects an accident in the bus direction based on the line-to-line sum current data from the line-to-line sum current generator A bus direction fault detection unit, and a direction discrimination processing unit that discriminates the direction of the fault point by comparing the size of the line sum current data from the line sum current generation unit and the line difference data from the difference current conversion unit. Is provided.

According to a fifth aspect of the present invention, there is provided a distance relay device, comprising: a difference circuit for generating difference data by subtracting current data from a current transformer; and adding data by adding current data from the current transformer. A current conversion unit for converting current data of each line into line-to-line current data; and a current conversion unit for converting current data of each line into line-to-line current data. Line current generator for generating line-to-line current data by adding line-to-line current data for each line from the line, and a bus direction accident based on the line-to-line current data from the line-to-line current generator. It is configured to include a bus direction accident detection unit to be detected, and a direction discrimination processing unit for discriminating the direction of the accident point by comparing the difference data from the difference circuit and the addition data from the addition circuit.

In the distance relay method according to the present invention, a sum current and a difference current are generated using current data, and the direction of the fault point is determined by comparing the sum current and the difference current. Things.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a configuration diagram showing a distance relay device according to Embodiment 1 of the present invention.
L is a transmission line, 31 is a bus, 32B1 and 32B2 are circuit breakers, and 33B1 and 33B2 are current transformers. An accident point 35 occurs at a point near the current transformer 33B1 of the transmission line 1L (closest to the current transformer 33B1 in the direction of the transmission line or inward). These configurations are the same as or correspond to the configurations in FIG. 8 described above. The load 3 and the power supply 3 in FIG.
0, circuit breakers 32A1, 32A2, current transformers 33A1, 33
A2 is omitted in FIG. 1, but is also connected in FIG. 1 in the same manner as in FIG. Further, in FIG. 1, a transformer for transforming the voltage values of the transmission lines 1L and 2L into voltage values proportional thereto is omitted.

Reference numeral 36 denotes a current transformer connected to the current transformer 33B1,
Transmission line 1L that converts the current value of the phase current of transmission line 1L output from 3B1 into data that can be input to arithmetic processing unit 38
The input converter 37 is connected to the current transformer 33B2, and converts the current value of the phase current of the transmission line 2L output from the current transformer 33B2 into data that can be input by the arithmetic processing unit 38. Is an input converter. 38 is an arithmetic processing unit,
The arithmetic processing unit 38 converts the phase current value IY into a line current value I △ for each line (each transmission line 1L, 2L) based on the data from the input converters 36 and 37, and By adding the line current values I 線_1L and I こ_{と 2L} , the sum current value (I △ _1L
+ I △ _2L ) to detect an accident in the direction of the bus 31, detect the sum current value (IY _1L + IY _2L ) and difference current value (IY _1L −) of the two lines using the phase current values IY _1L and IY _2L of each line. IY
_2L ) is derived to determine the direction of an accident in the inside or outside. The input converters 36 and 37 and the arithmetic processing unit 38 are mounted in the distance relay device. still,
The current relays other than the current transformers 33B1 and 33B2 are also provided with the distance relay device.

In the arithmetic processing unit 38, a reference numeral 50 designates a phase current value (current data) IY _1L of the transmission line 1L based on data from the input converter 36, based on a line current (line current data 0I).
A current conversion unit 51 for converting to ₁ L is a phase current value (current data) I of the transmission line 2 L based on data from the input converter 37.
A current conversion unit for converting Y _2L into a line current value (line current data) I △ _2L , 52 is a line current value I △ for two lines (transmission lines 1L and 2L) from the current conversion units 50 and 51. _1L and I △ _2L are added and the sum current value (line sum current data) (I △ _1L + I △
_2L ), the line-to-line sum current generator 53 is an input converter 3
The sum current value (phase sum current data) (IY _1L + IY _2L ) and the difference current value (phase difference current data) (IY _1L −IY _2L ) by adding and subtracting the phase current values IY _1L and IY _2L from 6, 37. Is a phase current deriving unit that derives a bus direction fault based on the sum current value (I △ _1L + I △ _2L ) from the line sum current generation unit 52. ),
55 is the sum current (IY _1L + IY) from the sum difference current deriving unit 53
_2L ) and a difference current (IY _1L −IY _2L ).

The above-described phase current IY and line current I △
Means, for example, that the currents Ia, Ib,
Ic is called a phase current, and a current Iab (= Ia) between transmission lines.
-Ib), Ibc (= Ib-Ic), Ica (= Ic-
Ia) is called line current.

FIG. 2 is a logic circuit diagram showing an algorithm of the distance relay device according to Embodiment 1 of the present invention. In FIG.
%, A first-stage protection element for detecting an accident in a section (transmission line-oriented accident detecting means, indicated by 44SX1 in FIG. 7), 11 is a first-stage protection element for detecting an accident in a section up to about 150% of the total impedance of the own section. A two-stage protection element (transmission line direction fault detection means, indicated by 44SX2 in FIG. 7), 12 is a third-stage protection element (transmission line direction detection) for detecting a fault in a section of 300 to 400% of the total impedance of the own section. Accident detection means, FIG.
And 44SI).

Reference numeral 13 denotes a blinder element for deriving the impedance in the direction of the transmission lines 1L and 2L from its own end (the installation point of the current transformers 33B1 and 33B2) and judging an accident (transmission line direction accident detecting means, indicated by 44SIR in FIG. 7) ), 14 are reactance elements which derive reactance in the direction of the bus 31 from their own ends and determine an accident (generating means for detecting bus direction, 44 in FIG. 7).
SOX), 15 is a Maw element for deriving an impedance in the direction of the bus 31 from its own end and judging an accident (a bus direction accident detecting means, indicated by 44SO in FIG. 7), and 16 is an impedance in the direction of the bus 31 from its own end. Blinder element derived and determined for an accident (bus direction accident detecting means, 44 in FIG. 7)
SOR). The derivation of the impedance and reactance of these elements is performed based on the current values and voltage values of the current transformers 33B1 and 33B2 provided on the transmission lines 1L and 2L and the transmission lines 1L and 2L extracted from the transformers. .

The above elements are the same as or correspond to those of the conventional distance relay device shown in FIG. Therefore,
Similar to the algorithm of the conventional distance relay device shown in FIG. 7, among the above elements, the first-stage protection element 10, the second-stage protection element 11, the third-stage protection element 12, and the blinder element 1
Reference numeral 3 denotes an element for detecting an accident in the direction of the transmission line 1 (inward), and the reactance element 14, the moh element 15 and the blinder element 16 are elements for detecting an accident in the direction of the bus 31 (external direction). The reactance element 14 and the moh element 15 are elements for detecting an accident in the direction of the bus 31.
The blinder element 16 operates according to the detection result of the bus direction accident detection unit 54 of the arithmetic processing unit 38.

Reference numeral 27 denotes a direction discriminating unit 5 of the arithmetic processing unit 38.
A direction discriminating element (direction discriminating means) that operates according to the direction discrimination of No. 5. Reference numerals 17 to 20 denote timed cooperative timers for shifting (delaying) the operation time of each stage (44ST1 to 44ST4 in FIG. 7).
The time for shifting the operation of the timers 17 to 20 is set in the order of the timers 20, 17, 18, and 19 from the shorter one. 21-
25 is an AND gate and 26 is an OR gate.

Next, the operation will be described. First, a case where a short-circuit accident or the like occurs at an accident point 35 near the inside of the transmission line 1L will be described. When an accident occurs at the accident point 35, an accident current flowing from the power supply 30 through the transmission line 1L side and an accident current flowing around through the transmission line 2L side flow through the accident point 35. Therefore, the current transformer 33 at the load 3 end
A current whose polarity is inverted flows into B1 and 33B2. At this time, since the fault point 35 is a fault that occurred at the nearest end in the direction of the transmission line 1L (inward), the current transformers 33B1, 33B
2 and a first-stage protection element 10 for detecting an accident in the direction of the transmission line 1L, 2L in the distance relay device from the impedance measured from the current value and the voltage value of the transformer (not shown).
Operates upon detecting an accident.

The phase current values of the transmission lines 1L and 2L from the current transformers 33B1 and 33B2 are converted into predetermined data by the input converters 36 and 37, and are converted into predetermined data.
0, 51 and the phase current deriving unit 53. The phase current values IY _1L and IY _2L output to the current converters 50 and 51 are
The current converters 50 and 51 convert the currents into line-to-line current values I ， _1L and I 出力_2L and output them to a line-to-line sum current generator 52. The line-to-line sum current generator 52 converts the lines of the transmission lines 1L and 2L. A sum current value of the inter-current values (I △ _1L + I △ _2L ) is generated. Then, based on the sum current value (I △ _1L + I △ _2L ), the bus direction accident detection unit 54 determines that the accident is in the bus 31 direction, and operates the elements 14 to 16 that detect the accident in the bus 31 direction. At this time, the error of the phase currents of the two current transformers 33B1 and 33B2 enters the operation range, so that the reactance element 14, which is an element for detecting an accident in the direction of the bus 31, operates. That is, due to an error between the two current transformers 33B1 and 33B2, it is erroneously determined to be an external accident even though the accident was originally an internal accident.

However, based on the sum current value (IY _1L + IY _2L ) and the difference current value (IY _1L −IY _2L ) from the phase current deriving unit 53, the direction discrimination processing unit 55 determines (1L phase current + 2L
Based on (phase current) <(1L phase current−2L phase current), it is determined that an accident has occurred in the direction of the transmission line, and the direction determination element 27 is not operated. Therefore, the lock is applied by the AND gate 23 provided in front of the timer 20, the final operation output is not reached, the accident is judged to be in the direction of the transmission line 1L, and only the circuit breaker 32B1 on the side of the transmission line 1L is opened to shut off the accident. I do.

Next, a case where an accident occurs in the direction of the bus 31 will be described. When an accident in the direction of the bus 31 occurs, the first-stage protection element at the own end (own section) does not operate, the second-stage protection element at the other end (other section) operates, and the timer 18
Is waiting for output for the time limit of. Before the final output of the other end, the external accident determination element of the own end is operated, and by the calculation of the direction determination element, (1 L phase current value + 2 L phase current value)> (1 L phase current value−2 L phase current value) And it is determined that the accident is in the direction of the bus 31. For this reason, the final operation signal of the own end is output, and the circuit breaker 32 of the own transmission lines 1L and 2L is output.
B1 and 32B2 are simultaneously opened to shut off the accident.

As described above, according to the first embodiment, based on the phase currents of the transmission lines 1L and 2L, the fault point is determined to be in the direction of the transmission lines 1L and 2L (inward) or in the direction of the bus 31 (outward). ) Accurately determines whether an accident is caused by an external accident, and does not activate the external accident discriminating element in the case of an inward accident. Therefore, an effect that optimal accident blocking can be performed can be obtained.

Embodiment 2 In the first embodiment, the direction discrimination processing of the direction discrimination element 27 is performed using the phase current value of each line, but in the second embodiment, the calculation is performed using the line current value of each line. is there. FIG. 3 is a configuration diagram showing such a distance relay device according to the second embodiment of the present invention. In the drawing, reference numeral 38A denotes an arithmetic processing unit, which corresponds to the arithmetic processing unit 38 of the first embodiment.

In the arithmetic processing section 38A,
50A is a transmission line 1L based on data from the input converter 36.
Current conversion unit that converts the phase current values IY _1L of the line between the current I △ _1L, 51A is the phase current values IY _2L of the transmission line 2L based on data from the input transducer 37 to the line current I △ _2L The current conversion unit for conversion, 52A is a current conversion unit from the current conversion units 50A, 51A.
Line-to-line current values I △ _1L , I の for the lines (transmission lines 1L, 2L)
Add _2L and add the sum current value (sum current data between lines) (I △ _1L +
A line-to-line sum current generating unit 53A for generating I △ _2L ) subtracts the line-to-line current values I △ _1L and I △ _2L from the current conversion units 50A and 51A to obtain a difference current value (line difference current data) ( I △ _1L -I △
_2L ), a bus-difference current detection unit (54A) detects a bus-direction fault based on the sum current value (I △ _1L + I △ _2L ) from the line sum current generation unit 52A. Direction accident detecting means), 55A are the sum current value (I △ _1L + I △ _2L ) from the line sum current generation unit 52A and the line difference current generation unit 5
A direction discriminating processing unit (direction discriminating means) for discriminating the direction of an accident in the inside direction or an accident in the outside direction based on the difference current value (I △ _1L− I △ _2L ) from 3A. Note that the other configuration is the same as the configuration shown in FIG. 1 described above, and a description thereof will be omitted.

Next, the operation will be described. When an accident occurs at an accident point 35 at the innermost end on the side of the transmission line 1L, as in the first embodiment, the first-stage protection element 1 of the distance relay device
0 detects an accident and operates. The processing for detecting an accident in the bus direction is performed in the same manner as in the first embodiment. Therefore, in the case of an internal near-end accident, the two current transformers 33B1,
Due to the error of 33B2, it is erroneously determined that the accident is an external accident although the accident is an internal accident.

However, in the second embodiment, the direction discrimination processing unit 55A determines the sum current value (I △ _1L + I △ _2L ) from the line sum current generation unit 52A and the difference from the line difference current generation unit 53A. Calculate based on the current value (I △ _1L- I △ _2L ), determine that the accident is in the direction of the transmission line by (1L line current + 2L line current) <(1L line current−2L line current), and Discriminant element 2
7 is not operated, the accident is determined to be an accident in the direction of the transmission line, and the accident is interrupted by opening only the circuit breaker 32B1 on the side of the transmission line 1L. Further, when the accident interruption in the bus direction occurs, it is determined that the accident is in the bus 31 direction as in the first embodiment, and the final operation signal of the own end is output, and the transmission lines 1L and 2L of the own end are output. The circuit breakers 32B1 and 32B2 are simultaneously opened to shut off the accident.

As described above, according to the second embodiment, based on the line currents of the transmission lines 1L and 2L, the fault point is determined to be an accident in the direction of the transmission lines 1L and 2L (inward) or the direction of the bus 31 (external direction). Direction), the external accident discriminating element is not operated in the case of an accident in the inner direction, so that even in the case of an internal near-end accident, the external An erroneous operation in which the accident discriminating element operates can be prevented, and an effect that an optimum accident cutoff can be performed can be obtained.

Embodiment 3 In the first and second embodiments, the data used for the direction discrimination processing is generated and calculated by software processing to operate the direction discrimination element. However, in the third embodiment, the line current The sum current uses data for detecting an accident in the bus direction, and the difference current between line currents performs direction discrimination processing using an output from a difference circuit configured by hardware. FIG. 4 is a configuration diagram showing such a distance relay device according to Embodiment 3 of the present invention. In FIG.
Reference numeral 9 denotes a difference circuit for differentiating the phase current values IY _1L and IY _2L taken from the current transformers 33B1 and 33B2.
9 is an input converter that converts the difference data from No. 9 into difference data that can be input to the arithmetic processing unit 38B.

In the arithmetic processing section 38B, 50B
Is a current converter for converting the phase current value IY _1L of the transmission line _1L into the line current I △ _1L based on the data from the input converter 36.
1B is a current converter for converting the phase current value IY _2L of the transmission line 2L into a line current value I △ _2L based on the data from the input converter 37, and 56B is a phase converter based on the data from the input converter 40. Current conversion unit for converting the differential data (IY _1L -IY _2L ) into differential data (line differential data) (I △ _1L + I △ _2L ) of the line current, and 52B is a differential current converter from the current converters 50B and 51B. The line-to-line current value I △ _1L of the line (transmission lines 1L and 2L),
Sum current value by adding the _{I △ 2L (I △ 1L +} I △ 2L) the line sum current generator for generating, 54B is the line between the sum current generator 52B
A bus direction fault detection unit (bus direction fault detection means) for detecting a bus direction fault on the basis of the sum current value ( _IL1L + I △ _2L ) from the controller, 55B is a sum current value from the line sum current generation unit 52B (55B) A direction discrimination processing unit (direction) that discriminates a direction of an accident in an internal direction or an accident in an external direction based on I △ _1L + I △ _2L ) and difference data (I △ _1L− I △ _2L ) from the difference current conversion unit 56B. Determination means). The other configuration is the same as the configuration shown in FIG. 1 or FIG. 3, and the description thereof will be omitted.

Next, the operation will be described. As in the first and second embodiments, when an accident occurs at the accident point 35 near the innermost end of the transmission line 1L, the distance connection is performed in the same manner as described in the first embodiment. The first-stage protection element 10 of the electric device detects an accident and operates. The processing for detecting an accident in the bus direction is also performed as described in the first embodiment. Therefore, in the case of an internal near-end accident, due to an error between the two current transformers 33B1 and 33B2, it is erroneously determined to be an external accident despite an internal accident.

However, in the third embodiment, the current value on the primary side of the input converters 36 and 37 (that is, the input converter 3
Current transformers 33B1, which have not been converted in
The current value from 33B2) is input to the difference circuit 39, and the difference circuit 39 generates difference data of the phase current value in hardware. Then, the difference data from the difference circuit 39 is converted by the input converter 40 into difference data (IY _1L −IY _2L ) that can be input to the arithmetic processing unit 38B, and the difference current conversion unit 56B converts the difference data of the phase current value. (IY _1L −IY _2L ) is converted into difference data (I △ _1L− I △ _2L ) of the line current value and output to the direction determination processing unit 55B. Direction determination processing unit 55
B is the sum current value (I △ _1L) from the line sum current generation unit 52B.
+ I △ _2L ) and the difference data (I △ _1L− I △ _2L ) from the difference current converter 56B, and (1L line current + 2
It is determined that the fault is in the direction of the transmission line based on (L line current) <(1L line current−2L line current). And the direction discriminating element 2
7 is not operated, an accident in the direction of the transmission line is determined, and only the circuit breaker 32B1 on the side of the transmission line 1L is opened to interrupt the accident. Further, when the accident interruption in the bus direction occurs, as described in the first embodiment, it is determined that the accident is in the bus 31 direction, the final operation signal of the own terminal is output, and the own transmission line 1L, The two-liter circuit breakers 32B1 and 32B2 are simultaneously opened to shut off the accident.

As described above, according to the third embodiment, as in the first and second embodiments, an accident in the direction of the transmission lines 1L and 2L (inward) or the direction of the bus 31 (outward) ) Can be accurately determined, and even in the case of an internal near-end accident, an effect of preventing a malfunction in which an external accident discriminating element operates and performing an optimal accident shutdown can be obtained.

Embodiment 4 FIG. In the first and second embodiments, data used for the direction discrimination processing is generated and operated by software processing to operate the direction discrimination element. In the fourth embodiment, the line current The sum current uses data for detecting an accident in the bus direction, and the difference current between line currents performs direction discrimination processing using an output from a difference circuit configured by hardware. In the fourth embodiment, data used for the direction determination processing is generated by a dedicated hardware configuration. FIG. 5 is a configuration diagram showing such a distance relay device according to Embodiment 4 of the present invention, in which 43B1 and 43B2 are current transformers, and 41 is a phase current value taken from current transformers 43B1 and 43B2. Is an input converter that converts the addition data from the addition circuit 41 into addition data (IY _1L + IY _2L ) that can be input to the arithmetic processing unit 38C.
The addition circuit 41 takes in the phase current values from the current transformers 43B1 and 43B2, but the current transformers 33B1 and 33B2
Alternatively, the phase current value may be taken in from.

In the arithmetic processing unit 38C, 50C
Is a current converter for converting the phase current value IY _1L of the transmission line _1L into the line current I △ _1L based on the data from the input converter 36.
1C is a current converter for converting the phase current value IY _2L of the transmission line 2L into a line current value I △ _2L based on the data from the input converter 37, and 52C is for two lines from the current converters 50C and 51C ( A line sum current generation unit that adds the line current values I △ _1L and I △ _2L of the transmission lines 1L and 2L) to generate a sum current value (I △ _1L + I △ _2L ), and 54C generates a line sum current A bus direction detecting unit (bus direction detecting means) for detecting a bus direction fault based on the sum current value (I （ _1L + I _2L ) from the unit 52C, 55C
Is the difference data (IY _1L -IY _2L ) from the input converter 40
And the addition data (IY _1L + I) from the input converter 43.
Y _2L ) is a direction discriminating processing unit (direction discriminating means) for discriminating the direction of an accident in the inside direction or an accident in the outside direction based on Y _2L .
The other configuration is the same as the configuration shown in FIG. 1, FIG. 3, or FIG. 4, and the description thereof will be omitted.

Next, the operation will be described. As in the case of the first, second and third embodiments,
When an accident occurs at the accident point 35 at the innermost end on the side of the transmission line 1L, the first-stage protection element 10 of the distance relay detects the accident and operates, as described in the first embodiment. I do. The processing for detecting an accident in the bus direction is also performed as described in the first embodiment. Therefore, in the case of an internal near-end accident, due to an error between the two current transformers 33B1 and 33B2, it is erroneously determined to be an external accident despite an internal accident.

However, in the fourth embodiment, the phase current value on the primary side of the input converters 36 and 37 (that is, the input converter 3
Current transformers 33B1, which have not been converted in
33B2) is input to the difference circuit 39,
Difference data of the phase current value is generated in hardware by the difference circuit 39, and the difference data from the difference circuit 39 is input to the input converter 40 and can be input to the arithmetic processing unit 38 </ b> C (IY _1L −IY _2L ). And outputs it to the direction determination processing unit 55C. Also, the phase current values from the current transformers 43B1 and 43B2 are input to the addition circuit 41, and the addition circuit 41 generates the addition data of the phase current values in hardware, and inputs the addition data from the addition circuit 41. Addition data (IY _1L + I) that can be input to the arithmetic processing unit 38C in the converter 42
Y _2L ) and outputs the result to the direction determination processing unit 55C. Then, the direction determination processing unit 55C performs an operation based on the difference data (IY _1L −IY _2L ) from the input converter 40 and the addition data (IY _1L + IY _2L ) from the input converter 42, and calculates (1L
It is determined that an accident in the direction of the transmission line has occurred based on (line current + 2L line current) <(1L line current−2L line current). Then, the direction discriminating element 27 is not operated, the accident is determined to be in the direction of the transmission line, and only the circuit breaker 32B1 on the side of the transmission line 1L is opened to shut off the accident. Further, when the accident interruption in the bus direction occurs, as described in the first embodiment, it is determined that the accident is in the bus 31 direction, the final operation signal of the own terminal is output, and the own transmission line 1L, 2L breaker 32B
1, 32B2 are simultaneously opened to shut off the accident.

As described above, according to the fourth embodiment, the first, second, and third embodiments are used.
Similarly to the above, it is possible to accurately determine whether the accident is in the direction of the transmission lines 1L and 2L (inward direction) or in the direction of the bus 31 (external direction). The effect of preventing an erroneous operation and performing optimal accident shutdown can be obtained.

[0049]

As described above, according to the first aspect of the present invention, the arithmetic processing unit mounted in the distance relay device includes:
Equipped with a transmission line direction fault detection means, and further with a bus direction fault detection means, generates a sum current and a difference current using current data, and compares the sum current and the difference current to determine the direction of the fault point. It is possible to detect not only an accident in the direction of the transmission line but also an accident in the direction of the bus. There is an effect that the direction of the accident can be determined.

According to the second aspect of the present invention, the arithmetic processing unit includes a transmission line direction fault detecting means, and further includes a current conversion unit for converting current data of each line into line-to-line current data; A line sum current generator for adding line current data for each line from the converter to generate line sum current data, and a sum current data and a phase difference by adding and subtracting current data for each line. A phase current deriving unit for deriving current data,
The fault is detected by comparing the bus direction fault detection unit that detects a bus direction fault based on the line sum current data from the line sum current generation unit with the phase sum current data and the phase difference current data from the phase current derivation unit. Since it is configured to have a direction discrimination processing unit that discriminates the direction of a point, it is possible to prevent a malfunction in which the discrimination element of an external accident operates even in the case of an internal near-end accident, and to perform an optimal accident shutdown. There is an effect that can be.

According to the third aspect of the present invention, the arithmetic processing section includes a transmission line direction fault detecting means, further includes a current conversion section for converting current data for each line into line current data, A line sum current generator for adding line current data for each line from the converter to generate line sum current data, and a line for subtracting line current data for each line from the current converter. A line-difference current generation unit that generates the difference current data;
A bus direction fault detection unit that detects a bus direction fault based on the line sum current data from the line sum current generation unit, and a line sum current data and a line difference current generation unit from the line sum current generation unit And a direction discrimination processing unit for discriminating the direction of the fault point by comparing the difference current data between the lines. It is possible to prevent an erroneous operation in which the accident discriminating element operates, and it is possible to perform an optimum accident cutoff.

According to the fourth aspect of the present invention, there is provided a differential circuit for generating difference data by subtracting current data from the current transformer, and the arithmetic processing unit includes a transmission line direction fault detecting means, Further, a current converter for converting current data for each line into line current data, and a line sum for generating line sum current data by adding line current data for each line from the current converter. A current generation unit, a difference current conversion unit for converting difference data from the difference circuit into line difference data, and a bus direction accident for detecting a bus direction accident based on the line sum current data from the line sum current generation unit A detection unit, and a direction discrimination processing unit that discriminates the direction of the accident point by comparing the magnitude of the line sum current data from the line sum current generation unit and the line difference data from the difference current conversion unit. Used for direction determination processing Data can be generated by hardware, and at the same time as in the case of the above-described second aspect, even in the case of an internal near-end accident, a malfunction in which an external accident discriminating element operates can be prevented. There is an effect that the accident can be cut off.

According to the fifth aspect of the present invention, a difference circuit for generating difference data by subtracting current data from a current transformer, and an addition circuit for adding current data from a current transformer to generate addition data. A current conversion unit for converting current data for each line into line-to-line current data; and a circuit for converting each line from the current conversion unit. A line-to-line sum current generator that adds line-to-line current data to generate line-to-line sum current data, and a bus line direction that detects a bus direction accident based on the line-to-line current data from the line-to-line sum current generator An accident detection unit and a direction discrimination processing unit for discriminating the direction of an accident point by comparing the difference data from the difference circuit and the addition data from the addition circuit with each other are used for the direction discrimination processing. Data in hardware At the same time, in the same manner as in the second aspect of the invention, it is possible to prevent a malfunction in which an external accident discriminating element operates even in the case of an internal near-end accident, and to perform an optimal accident shutdown. The effect that can be obtained is obtained.

According to the sixth aspect of the present invention, a sum current and a difference current are generated using current data, and the direction of the fault point is determined by comparing the sum current and the difference current. Similar to the invention described in 1 above, it is possible to detect not only an accident in the direction of the transmission line but also an accident in the direction of the bus, and even in the case of an internal near-end accident, the direction of the accident can be reliably determined without erroneous determination as an external accident. There is an effect that determination can be made.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a distance relay device according to Embodiment 1 of the present invention.

FIG. 2 is a logic circuit diagram showing an algorithm of the distance relay device according to the first embodiment of the present invention.

FIG. 3 is a configuration diagram showing a distance relay device according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram showing a distance relay device according to Embodiment 3 of the present invention.

FIG. 5 is a configuration diagram showing a distance relay device according to Embodiment 4 of the present invention.

FIG. 6 is a schematic diagram showing an accident occurrence system.

FIG. 7 is a logic circuit diagram showing an algorithm of a conventional distance relay device.

FIG. 8 is a schematic diagram showing an accident occurrence system different from that shown in FIG.

[Explanation of symbols]

1L, 2L transmission line, 10 first stage protection element (transmission line direction accident detection means), 11 second stage protection element (transmission line direction detection unit), 12 third stage protection element (transmission line direction detection unit) , 13 Blinder element (transmission line direction detecting means), 14 Reactance element (bus direction detecting means), 15 Mo element (bus direction detecting means), 16 Blinder element (bus direction detecting means), 27 direction discriminating element (Direction determining means), 31 busbars, 32B1, 32B2 circuit breakers, 33B1, 33B
2,43B1,43B2 Current transformer, 38,38A, 38
B, 38C arithmetic processing unit, 39 difference circuit, 41 addition circuit, 50, 51, 50A, 51A, 50B, 51B, 5
0C, 51C Current converter, 52, 52A, 52B, 5
2C Line-to-line sum current generation unit, 53-phase current derivation unit, 53A
Line difference current generator, 54, 54A, 54B, 54C
Bus direction accident detection unit (bus direction accident detection means), 55,
55A, 55B, 55C Direction discrimination processing section (direction discrimination means), 56B difference current conversion section.

Claims (6)

[Claims] 1. A current transformer and a transformer collectively take in current data and voltage data for two lines of a transmission line, measure a distance from an installation point to an accident point based on these data, and determine an operation time limit. In the distance relay device that determines and selectively interrupts the circuit breaker, the arithmetic processing unit mounted in the distance relay device includes a transmission line direction accident detection unit, and further includes a bus line direction accident detection unit. A distance relay device comprising a direction discriminating means for generating a sum current and a difference current using current data, and comparing the sum current and the difference current to determine the direction of an accident point. 2. An arithmetic processing unit comprising a transmission line direction fault detecting means, further comprising: a current conversion unit for converting current data of each line into line-to-line current data; A line sum current generator for adding line current data to generate line sum current data, and a phase current deriving unit for adding and subtracting current data for each line to derive phase sum current data and phase difference current data And a bus direction fault detector that detects a bus direction fault based on the line sum current data from the line sum current generator, and a phase sum current data and a phase difference current data from the phase current derivation unit. The distance relay device according to claim 1, further comprising: a direction determination processing unit that determines a direction of the accident point by performing the determination. 3. An arithmetic processing unit comprising a transmission line direction fault detecting means, further comprising: a current conversion unit for converting current data of each line into line-to-line current data; A line-to-line sum current generator that adds line-to-line current data to generate line-to-line sum current data, and subtracts line-to-line current data for each line from the current converter to generate line-to-line difference current data. A line difference current generator, a bus direction fault detector for detecting a bus direction fault based on the line sum current data from the line sum current generator, and a line sum from the line sum current generator. 2. The distance joint according to claim 1, further comprising a direction discriminating processing unit that discriminates the direction of the fault point by comparing the magnitude of the current data and the line difference current data from the line difference current generating unit. Electrical equipment. 4. A differential circuit for generating differential data by subtracting current data from a current transformer, an arithmetic processing unit including a transmission line direction fault detecting means, and further comprising: To a line current data, a line sum current generator for adding line current data for each line from the current converter to generate line sum current data, and the difference circuit A difference current conversion unit for converting the difference data from the line-to-line difference data, a bus-line fault detection unit for detecting a bus-direction fault based on the line-to-line sum current data from the line-to-line sum current generation unit, A direction discriminating unit for discriminating the direction of the fault point by comparing the line sum current data from the line sum current generating unit with the line difference data from the difference current converting unit; The distance relay device according to claim 1. 5. A differential circuit for generating difference data by subtracting current data from a current transformer, and an adding circuit for adding current data from the current transformer to generate addition data. The arithmetic processing unit includes a transmission line direction accident detection unit, and further converts a current data for each line into line current data, and a line current data for each line from the current conversion unit. A line sum current generating unit that adds and generates line sum current data, a bus direction fault detection unit that detects a bus direction fault based on the line sum current data from the line sum current generating unit, The distance relay device according to claim 1, further comprising: a direction discrimination processing unit that discriminates the direction of the accident point by comparing the difference data from the difference circuit and the addition data from the addition circuit with each other. 6. A current transformer and a transformer collectively take in current data and voltage data of two lines of a transmission line, and measure a distance from an installation point to an accident point based on impedance obtained from these data. In a distance relaying method of determining an operation time limit and detecting a transmission line direction fault or a bus direction fault and selectively cutting off a circuit breaker, a sum current and a difference current are generated using the current data, and the sum current and the difference current are generated. A distance relay method characterized by determining the direction of an accident point by comparing the difference currents.