JP2008136263A - Distance relay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a distance relay which can sharply shorten an accident removal time at occurrence of a short circuit accident without including a transmission path for a transfer signal from a counter terminal. <P>SOLUTION: A trip signal generating circuit 20 includes an increment comparing circuit 25 which generates a high level of output signal when the increment ΔI<SB>1</SB>of a first line current I<SB>1</SB>is not less than a first threshold K<SB>1</SB>, a decrement comparing circuit 26 which generates a high level of output signal when the decrement ΔI<SB>2</SB>of a second line current I<SB>2</SB>is not less than a second threshold K<SB>2</SB>, a fourth logical product circuit 23<SB>4</SB>which takes the logical product of the output signal of the increment comparing circuit 25 and the output signal of the decrement comparing circuit 26, and a fifth logical product 23<SB>5</SB>which takes the logical product of the output signal of the fourth logical product circuit 23<SB>4</SB>and the contact signal S<SB>C2</SB>input from the second breaker 4<SB>2</SB>in another circuit 2L. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a distance relay device, and more particularly, to a distance relay device suitable for installation on a power source end side, an opposite end side, and a load end side of a balanced two-line power transmission line.

  A three-stage distance relay system is used to protect balanced two-line transmission lines. In the three-step distance relay system, the short-circuit distance relay device (DZ) is, for example, the first protection section (the first-stage operation area A1 of the short-circuit distance relay device) up to 80% of the own line that is the protection section transmission line. For the short-circuit accident of the second, the second protection section (2 of the short-circuit distance relay device) is set so that the circuit breaker is shut off instantaneously (first time coordination time ST1 = 0 s) and up to 150% of the own line. For short-circuit accidents in the stage operating range A2), the third protective section (short-circuit) is set up to shut off the circuit breaker after the second time-coordinated time ST2 (for example, 400 ms) has elapsed, up to 300% of the own line. For short-circuit accidents in the three-step operation range A3) of the distance relay device, the circuit breaker is set to shut off after the third time coordination time ST3 (for example, 1.5 s) has elapsed, so Set the distance to the short-circuit distance relay for protecting the wire. Thereby achieving the coordination of beauty time settling.

The operation of the short-circuit distance relay device used in such a three-step distance relay system will be described with reference to FIG.
A first power transmission line 1L (hereinafter referred to as “own line 1L”) and a second power transmission line 2L (hereinafter referred to as “other line 2L”) branched from a bus to which power is supplied from the power source 1. A short-circuit distance relay device (hereinafter referred to as “first and second power-source distance relay devices 110 ₁ , 110 ₂ ”) is installed on the power source end side (bus side). Also, the short-circuit distance relay device (hereinafter referred to as “first and second counter-end distance relay devices 120 ₁ , 120 ₂ ”) is also provided on the opposite end side (the opposite side of the bus) of the own line 1L and the other line 2L. Respectively).

First power supply terminal distance relay apparatus 110 ₁ includes a first current transformer provided on the power terminal side of the bus voltage Va and the own line 1L inputted from the first transformer 2 ₁ provided in bus A _first impedance Z ₁ (Z ₁ = Va / I ₁ ) is calculated based on the first line current I ₁ input from 3 ₁ . When the first power supply end distance relay device 110 ₁ detects the occurrence of a short-circuit accident in the own line 1L based on the calculated first impedance Z ₁ , the first interruption is provided on the power supply end side of the own line 1L. A first trip signal S ₁ for interrupting the device 4 ₁ is generated.
Relay device 110 ₂ and the second power supply terminal distance, power source terminal of the bus voltage Va and the other line 2L inputted from the first transformer 2 ₁ (second power supply terminal distance relay apparatus 110 ₂ of its own line) A second impedance Z ₂ (Z ₂ = Va / I ₂ ) is calculated based on the second line current I ₂ input from the _second current transformer 3 ₂ provided on the side. When detecting the occurrence of a short circuit in the other line 2L based on the calculated second impedance Z ₂ , the second power supply end distance relay device 110 ₂ detects the second interruption provided on the power supply end side of the other line 2L. A second trip signal S ₂ for interrupting the device 4 ₂ is generated.

The first opposing end distance relay device 120 ₁ includes an opposing end bus voltage Vb input from a _second transformer 22 provided on the opposing end bus (hereinafter referred to as “opposing end bus”). Based on the third line current I ₃ input from the third current transformer 3 ₃ provided on the opposite end side of the own line 1L, the third impedance Z ₃ (Z ₃ = Vb / I ₃ ) is obtained. calculate. When the first opposing end distance relay device 120 ₁ detects the occurrence of a short-circuit accident in the own line 1L based on the calculated third impedance Z ₃ , the third cutoff circuit provided on the opposing end side of the own line 1L A third trip signal S ₃ for interrupting the device 4 ₃ is generated.
Second opposing end distance relay apparatus 120 _2, the second transformer 2 ₂ opposing ends inputted from the bus voltage Vb and another line 2L (second opposing end distance relay apparatus 120 ₂ of its own line) A fourth impedance Z ₄ (Z ₄ = Vb / I ₄ ) is calculated based on the fourth line current I ₄ input from the _fourth current transformer 3 ₄ provided on the opposite end side. When the second opposing end distance relay device 120 ₂ detects the occurrence of a short circuit accident in the other line 2L based on the calculated fourth impedance Z ₄ , the fourth cutoff provided in the opposing end side of the other line 2L. generating a fourth trip signal S ₄ of for blocking vessels 4 _4.

Next, the first to fourth trip signals S ₁ in the first and second power supply end distance relay devices 110 ₁ , 110 ₂ and the first and second opposing end distance relay devices 120 ₁ , 120 _2. the method of generating to S _4, will be described with reference to FIGS. 15 to 17 the first generation method of the trip signals S ₁ at the first power supply terminal distance relay apparatus 110 ₁ as an example.
As shown in FIG. 15, the trip signal generation circuit 220 for generating the first trip signal S ₁ is based on the bus voltage Va and the first line current I _{1. The} operation region determination circuit 221 for determining the operation region of ₁ and the second and third determination result output signals VD ₂ and VD ₃ input from the operation region determination circuit 221 are used as the second and third time-coordinated times ST2, Logical product of first and second delay circuits (timers) 222 ₁ and 222 ₂ that are delayed by ST3, respectively, and first and third determination result output signals VD ₁ and VD ₃ that are input from the operation range determination circuit 221 A second logical product of the first logical product circuit 223 ₁ which takes the logical product of the second judgment result output signal VD ₂ delayed by the _first delay circuit 222 ₁ and the third judgment result output signal VD ₃ aND circuit 223 _2, A third determination result output signal VD ₃ and the first and second AND circuit 223 _1, 223 OR circuit 224 for taking a logical sum of the _second output signal delayed by the second delay circuit 222, _second And a third logical product circuit 223 ₃ that takes a logical product of the first FD relay output signal _SFD1 from one failsafe FD relay (not shown) and the output signal of the logical sum circuit 224.

The operating area determination circuit 221 calculates the first impedance Z ₁ (Z ₁ = Va / I ₁ ) by dividing the bus voltage Va by the first line current I ₁ . The operating area determination circuit 221 determines the operating area of the first power supply end distance relay device 110 ₁ based on the calculated first impedance Z _1, and _first to third determination result output signals indicating the determination results. VD _{1 to} VD ₃ are output.
That is, the operation area determination circuit 221, as shown in FIG. 16, when the reactance X ₁ of the first impedance Z ₁ is the first value B ₁ below, the "first power supply terminal distance relay device 110 operation area of ₁ is determined to be a "one-stage operation zone A1, and outputs the first determination result output signal VD ₁ of high level. In addition, when the reactance component X ₁ of the _first impedance Z ₁ is equal to or less than the second value B ₂ , the operating range determination circuit 221 indicates that “the operating range of the first power supply distance relay device 110 ₁ is two stages. it is determined that the operation zone A2 ", and outputs a second determination result of the high level output signal VD _2. Further, when the resistance R ₁ and reactance X _{1 of} the first impedance Z ₁ are within the circle in FIG. 16, the operating range determination circuit 221 determines that “the first power supply distance relay device 110 ₁ it is determined that the operation zone is a three-stage operation region A3 ", and outputs a third determination result output signal VD ₃ at a high level.

For example, Figure a first power supply terminal distance relay apparatus 110 ₁ of the first guard interval in its own line 1L (first-stage operation zone A1 of the power supply end distance relay apparatus 110 ₁₎ shown in FIG. 14 17 ( When a short circuit accident occurs at time t ₀ shown in a) and the first impedance Z ₁ becomes the value indicated by the point P ₁ in FIG. 16, the operating range determination circuit 221 determines the first impedance Z _1. Based on the above, it is determined that “the operating range of the first power supply end distance relay device 110 ₁ is the one-stage operating range A1”, and the high-level first determination result output signal VD ₁ is output. Further, since the first impedance Z ₁ is also included in the circle of FIG. 16, the operating range determination circuit 221 also outputs a high-level third determination result output signal VD ₃ .
When the high-level first and third output signals VD ₁ and VD ₃ are input, the output signal of the first AND circuit 223 ₁ changes from the low level to the high level, so that the output signal of the OR circuit 224 is low level. To high level. As a result, when the first FD relay output signal S _FD1 is at a high level, the output signal of the _third AND circuit 223 ₃ is changed from a low level to a high level, so that the first trip signal S ₁ is generated as a trip signal. output from the circuit 220 to the first breaker 4 _1. The first trip signal S ₁ is output from the trip signal generation circuit 220 at time t ₁ when the relay determination time T _RY (50 ms) in the first power supply end distance relay device 110 ₁ has elapsed.
Thus, for the first breaker 4 ₁ for blocking is complete after a circuit breaker interruption time T _CB (50 ms) from the input of the first trip signal S ₁ is the first breaker 4 _1, As shown in FIG. 17A, the relay is completely cut off at time t ₂ when the total time (= 50 ms + 50 ms = 100 ms) of the relay determination time T _RY and the breaker breaking time T _CB has elapsed.

On the other hand, in the second protection section (the two-stage operation area A2 of the first power supply distance relay device 110 ₁ ) of the first power supply distance relay device 110 ₁ in the own line 1L shown in FIG. When a short circuit accident occurs at time t ₀ shown in b) and the first impedance Z ₁ becomes the value indicated by the point P2 in FIG. 16, the operating range determination circuit 221 determines the first impedance Z _1. Based on the above, it is determined that “the operating range of the first power supply end distance relay device 110 ₁ is the two-stage operating range A2”, and the high-level second output signal VD ₂ is output. In addition, since the first impedance Z ₁ is also included in the circle of FIG. 16, the operating range determination circuit 221 also outputs a high-level third output signal VD ₃ .
The second output signal VD ₂ is input by the _first delay circuit 222 ₁ to the second AND circuit 223 ₂ after being delayed by the second time cooperation time ST 2 (400 ms).
When the output signal of the first delay circuit 222 _{1 having} the high level and the third output signal VD ₃ having the high level are input, the output signal of the second AND circuit 223 ₂ changes from the low level to the high level. The output signal of the sum circuit 224 changes from low level to high level.
As a result, when the first FD relay output signal S _FD1 is at a high level, the output signal of the _third AND circuit 223 ₃ is changed from a low level to a high level, so that the first trip signal S ₁ is generated as a trip signal. output from the circuit 220 to the first breaker 4 _1. The first trip signal S ₁ is the time t when the total time (= 50 ms + 400 ms = 450 ms) of the relay determination time T _RY and the second time limit coordination time ST 2 in the first power supply end distance relay device 110 ₁ has elapsed. ₅ is output from the trip signal generation circuit 220.
Accordingly, the first breaker 4 _1, as shown in FIG. 17 (b), the relay determination time T _RY, the total time of the second timed coordination time ST2 and breaker interruption time _{T CB (= 450ms + 50ms =} 500ms ) is completely cut off to time t ₆ has elapsed.

Patent Document 1 listed below ensures accident interruption selectivity and enables high-speed interruption in a protective relay device having a back-end protection means that protects a three-terminal transmission line by a distance relay method with a stage limit. Therefore, the means for transmitting the operating condition of the second stage relay for detecting the accident in the opposite bus direction including the opposite bus, the means for receiving the transfer signal from the opposite end, and the operation of the protection relay at its own end are received. A protective relay device is disclosed that includes a means for outputting a break command to a self-breaker provided that the transfer signal continues for a predetermined time or longer.
JP-A-5-76134

However, in the first power supply terminal distance relay apparatus 110 ₁ as described above, the first power supply terminal distance relay apparatus 110 ₁ of the second guard interval in its own line 1L (first power supply terminal distance relay apparatus 110 ₁ If the short-circuit failure occurs in two stages operating region A2) is of the first breaker 4 ₁ accident occurrence time t ₀ from the relay determination time T _RY, second timed coordination time ST2 and breaker interruption time T _Since it is cut off at time t ₆ when the total time of _CB (= 500 ms) has elapsed (see FIG. 17B), it takes time to eliminate this short-circuit accident, and there is a problem of adversely affecting the equipment. .
The first opposing end distance relay apparatus 120 even _1, the first opposing end distance relay apparatus 120 ₁ of the second guard interval in its own line 1L (the first opposing end distance relay apparatus 120 ₁ 2 When a short-circuit accident occurs in the stage operation region A2), it takes time to remove the short-circuit accident in the same manner, and there is a problem that the equipment is adversely affected.

In the protection relay device described in Patent Document 1, a short circuit accident occurs in the second protection section of the first power supply end distance relay device 110 ₁ and the first opposite end distance relay device 120 ₁ in the own line 1L. Although the accident elimination time can be shortened sometimes, it is a system that shuts off the circuit breaker of its own terminal by continuously receiving the transfer signal from the opposite terminal (power supply end or opposite end). There is a problem that a transmission line is necessary.

  An object of the present invention is to provide a distance relay device for a power supply end, an opposite end, and a load end, which can greatly reduce the accident removal time when a short circuit accident occurs without providing a transmission path for a transfer signal from the opposite terminal. Is to provide.

The distance relay apparatus according to the present invention is a self-contained power transmission system for a balanced two-line power transmission line composed of a self-line (1L) and another line (2L) laid between a power-supply-side bus and a counter-end bus. The self-branching line of the balanced two-line power transmission line further including a self-branching line (3L) and another branching line (4L) branched from the own line and the other line at the power source side or the opposite end of the line A distance relay device (10 ₁ ; 30 ₁ ; 50 ₁ ) installed on the load end side, provided on the own line or the own branch line when an accident occurrence in the own line or the own branch line is detected. A trip signal generating circuit (20; 40; 60) for generating a trip signal (S ₁ ; S ₃ ; S ₅ ) for breaking the circuit breaker (4 ₁ ; 4 ₃ ; 4 ₅ ) A trip signal generation circuit flows through the own line or the own branch line. Own line current _{(I 1; I 3; I} 5) and the other lines or the other branch flow line other line current _{(I 2; I 4; I} 6) power supply terminal side of the self-line based on the amount of change Alternatively, it is characterized by comprising trip signal generating means for instantaneously generating the trip signal when the occurrence of an accident at the opposite end side is detected.
Here, the trip signal generating means is interrupted by an adjacent line breaker (4 ₂ ; 4 ₄ ; 4 ₆ ) installed on the power supply end side or the opposite end side of the other line or the load end side of the other branch line. If the occurrence of an accident on the power source end side or the opposite end side of the own line is detected based on the change amount of the own line current and the other line current on the condition that the trip signal is not generated, Good.
The trip signal generating means has an increase amount (ΔI ₁ ; ΔI ₃ ; ΔI ₅ ) of the own line current equal to or greater than a predetermined threshold (K ₁ ; K ₃ ; K ₅ ), and a decrease in the other line current. On the condition that the amount (ΔI ₂ ; ΔI ₄ ; ΔI ₆ ) is equal to or greater than a predetermined threshold value (K ₂ ; K ₄ ; K ₆ ), it is based on the change amount of the own line current and the other line current. The trip signal may be generated instantaneously upon detecting the occurrence of an accident on the power supply end side or the opposite end side of the own line.
The threshold value and the other threshold value may be a value that is three times or more the minimum detectable value of the own line current and the other line current.
Change amount (ΔVa) of bus voltage (Va) of the bus, change amount (ΔVb) of opposite end bus voltage (Vb) of the opposite end bus, or load end bus voltage (Vc) of the load end bus on the load end side The trip signal may be instantaneously generated on the condition that the amount of change (ΔVc) is equal to or greater than another predetermined threshold value (K ₇ ).
The trip signal generating means is configured such that when the increase amount of the own line current is equal to or greater than the threshold value and the decrease amount of the other line current is equal to or more than the other threshold value, The trip signal may be generated instantaneously by determining that another circuit breaker (4 ₁ ; 4 ₃ ) installed on the end side has been disconnected due to an accident in the own line.
The trip signal generation means obtains an increase amount of the own line current, and an increase amount comparison circuit (25; 45; 65) for generating an output signal when the obtained increase amount is equal to or greater than the threshold; and the other line A decrease amount comparison circuit (26; 46; 66) for obtaining a decrease amount of the current, and generating an output signal when the calculated decrease amount is equal to or greater than the other threshold, and an output signal of the increase amount comparison circuit and the decrease A logical product circuit (23 ₄ ; 43 ₄ ; 63 ₄ ) that takes a logical product with the output signal of the quantity comparison circuit may be provided.
The trip signal generating means is another logical product circuit (23 ₅ ) that takes the logical product of the output signal of the logical product circuit and the contact signal (S _C2 ; S _C4 ; S _C6 ) input from the adjacent circuit breaker. ; 43 ₅ ; 63 ₅ ).
Other distance relay devices (10 ₂ ; 30 ₂ ; 50 ₂ ) installed on the power supply terminal side or the opposite end side of the other line or the load end side of the other branch line have the same configuration as the distance relay apparatus. And may be configured integrally.

The distance relay device of the present invention has the following effects.
(1) Since the trip signal is generated based on the change amount of the own line current flowing in the own line or the own branch line and the other line current flowing in the other line or the other branch line, the signal from the opposite terminal (power supply end or opposite end) is generated. There is no need to provide a transmission path for the transfer signal.
(2) Since a trip signal can be generated without waiting for the second timed coordination time ST2, it is possible to greatly reduce the time for removing an accident that has occurred in the second protection section of the own line.
(3) Since the accident continuation time is also greatly shortened, the adverse effects on the facilities at the time of the accident can be reduced.
(4) Since it is possible to omit the main protection relay device, the investment cost to the facility can be reduced.

  If the occurrence of an accident on the opposite terminal side of the own line is detected based on the amount of change in the own line current flowing in the own line or the own branch line and the other line current flowing in the other line or the other branch line, the trip signal is instantaneously It was realized by occurring.

Hereinafter, embodiments of the distance relay device of the present invention will be described with reference to the drawings.
First power supply terminal distance relay apparatus 10 ₁ is a distance relay apparatus according to a first embodiment of the present invention, before and after the third shut-off of the circuit breaker 4 ₃ installed on the opposite end of its own line 1L A first trip for breaking the _first circuit breaker 4 ₁ when the occurrence of a short circuit accident on the opposite end side of the own line 1L is detected based on the amount of change in the first and second line currents I ₁ and I ₂ It differs from the conventional first power supply end distance relay device 110 ₁ shown in FIG. 14 in that it has a function of generating the signal S ₁ instantaneously.

That is, in the first power supply end distance relay device 10 ₁ shown in FIG. 1, the increase amount ΔI _{1 of the first} line current I ₁ input from the _first current transformer 3 ₁ is a predetermined first threshold value. K ₁ (for example, 120 mA when the minimum detectable value of the first line current I ₁ is 40 mA) or more, and the second line current I input from the _second current transformer 3 _{2. 2} of decrease [Delta] I ₂ second threshold is predetermined K ₂ (for example, if the minimum detectable value of the second line current I ₂ of 40mA is 120 mA) or more, and, next to its own line 1L The second contact signal S _C2 inputted from the second circuit breaker 4 ₂ installed on the power supply end side of the other line 2L that is a line is at a high level (the second circuit breaker 4 ₂ is not cut off). The first trip signal S ₁ is instantaneously generated on the condition that
To achieve this, the first power supply terminal distance relay apparatus 10 _1, instead of the trip signal generating circuit 220 shown in FIG. 15 comprises a trip signal generating circuit 20 shown in FIG.

As shown in FIG. 2, the trip signal generation circuit 20 includes an operating range determination circuit 21, first and second delay circuits (timers) 22 ₁ and 22 _2, and first to sixth AND circuits 23 _1. ˜ 23 ₆ , an OR circuit 24, an increase amount comparison circuit 25, and a decrease amount comparison circuit 26.

Operation area determination circuit 21, similarly to the operation region determination circuit 221 shown in FIG. 15, a first impedance Z ₁ on the basis of the bus voltage Va and the first line current I ₁ (Z ₁ = Va / I ₁ ) Is calculated, and the operating range of the first power supply distance relay device 10 ₁ is determined based on the calculated first impedance Z ₁ .
That is, the operating range determination circuit 21 indicates that the reactance component X ₁ of the first impedance Z ₁ is equal to or less than the first value B ₁ as indicated by a point P1 in FIG. It is determined that the operating range of the electric device 10 ₁ is the one-stage operating range A1, and the first determination result output signal VD ₁ having a high level is output. Further, as shown by the point P2 in FIG. 16, the operating range determination circuit 21 determines that the reactance component X ₁ of the _first impedance Z ₁ is equal to or less than the second value B _2. It is determined that the operating range of the electric device 10 ₁ is the two-stage operating range A2, and the high-level second determination result output signal VD ₂ is output. Further, when the resistance R ₁ and reactance X _{1 of} the first impedance Z ₁ are within the circle of FIG. 16, the operating range determination circuit 21 determines that “the first power supply distance relay device 10 ₁ it is determined that the operation zone is a three-stage operation region A3 ", and outputs a third determination result output signal VD ₃ at a high level.

The first and second delay circuits 22 ₁ and 22 ₂ are the same as the first and second delay circuits 222 ₁ and 222 ₂ shown in FIG. 3 determination result output signals VD ₂ and VD ₃ are delayed by the second and third time cooperation times ST2 and ST3, respectively.

The first AND circuit 23 ₁ is similar to the _first AND circuit 223 ₁ shown in FIG. 15, and the first and third determination result output signals VD ₁ and VD input from the operation area determination circuit 21. Logical AND of ₃ .
Similarly to the _second logical product circuit 223 ₂ shown in FIG. 15, the second logical product circuit 23 ₂ receives the second determination result output signal VD ₂ delayed by the _first delay circuit 22 ₁ and the third logical product circuit 223 ₂ . ANDing the determination result output signal VD ₃ of.
The third logical product circuit 23 ₃ takes the logical product of the second and third determination result output signals VD ₂ and VD ₃ input from the operation region determination circuit 21.
The increase amount comparison circuit 25 obtains an increase amount ΔI ₁ of the first line current I ₁ , and generates a high-level output signal when the obtained increase amount ΔI ₁ is equal to or greater than the first threshold value K ₁ .
The reduction amount comparison circuit 26 obtains a reduction amount ΔI ₂ of the second line current I ₂ , and generates a high level output signal when the obtained reduction amount ΔI ₂ is equal to or greater than the second threshold value K ₂ .
The fourth logical product circuit 23 ₄ takes a logical product of the output signal of the increase amount comparison circuit 25 and the output signal of the decrease amount comparison circuit 26.
The fifth AND circuit 23 ₅ calculates the logical product of the output signal of the _third AND circuit 23 ₃ , the output signal of the fourth AND circuit 23 ₄ , and the second contact signal S _C2 .
The logical sum circuit 24 outputs the output signal of the _first logical product circuit 23 ₁ , the output signal of the second logical product circuit 23 ₂ , the output signal of the second delay circuit 22 ₂ , and the fifth logical product circuit 23 ₅ . Logical OR with the output signal.
The sixth logical product circuit 23 ₆ takes a logical product of the first FD relay output signal _SFD1 from the first failsafe FD relay and the output signal of the logical sum circuit 24.

Next, short circuit at the first power supply terminal distance relay apparatus 10 ₁ in the second guard interval in its own line 1L (first two-stage operation region A2 of the power supply end distance relay apparatus 10 ₁₎ shown in FIG. 1 The operation of the trip signal generation circuit 20 when this occurs will be described with reference to FIG.

When a short circuit accident occurs at time t ₀ shown in FIG. 3 in the second protection section, the trip signal generating circuit provided in the first opposite end distance relay device 120 ₁ installed on the opposite end side of the own line 1L. Calculates a _third impedance Z ₃ (Z ₃ = Vb / I ₃ ) based on the opposite-end bus voltage Vb and the third line current I ₃ , and calculates the first impedance based on the calculated third impedance Z ₃ . When the occurrence of a short circuit accident in the one-stage operation area A1 of the opposite end distance relay device 120 ₁ is detected, a third trip signal S ₃ for breaking the third breaker 4 ₃ is sent to the first opposite end distance relay. It occurs at time t ₁ after elapse of the relay determination time T _RY (50 ms) in the electric device 120 ₁ . As a result, the third circuit breakers 4 _3, as shown in FIG. 3, a relay determination time in the first opposing end distance relay apparatus 120 ₁ T _RY and breaker interruption time T _CB (50 ms) total time ( = 50 ms + 50 ms = 100 ms), and completely cut off at time t ₂ after elapse.

On the other hand, in the first power supply terminal distance relay apparatus 10 ₁ installed on the power terminal side of the own line 1L, the accident occurrence time t ₀ to time t ₂ the third breaker 4 ₃ is completely cut off the Since the impedance Z _{1 of 1} becomes the value indicated by the point P2 in FIG. 16, the operating range determination circuit 21 of the trip signal generation circuit 20 calculates the _first value calculated based on the bus voltage Va and the first line current I ₁ . since reactance X ₁ of the first impedance Z ₁ is the first value B ₁ large and the second value B ₁ or less than, the operation range of the "first power supply terminal distance relay apparatus 10 ₁ bunk it is determined that the operation zone A2 ", and outputs a second determination result of the high level output signal VD _2. Further, since the first impedance Z ₁ is also included in the circle of FIG. 16, the operation region determination circuit 21 also outputs a high-level third determination result output signal VD ₃ . As a result, the output signal of the _third AND circuit 23 ₃ becomes high level.
However, if the second and fourth circuit breakers 4 ₂ and 4 ₄ installed on the power supply terminal and the opposite terminal side of the other line 2L are not interrupted, the third circuit breaker 4 from the accident occurrence time t ₀ . Until time t ₂ when ₃ is completely cut off, the fault current flows in the local line 1L and the other line 2L toward the fault point. Therefore, the first and second line currents I ₁ and I ₂ are shown in FIG. , (B), it remains increased. As a result, even if the first line current I ₁ increases by an increase amount ΔI ₁ (ΔI ₁ ≧ K ₁ ) equal to or greater than the _first threshold value K _{1, a} high level output signal is output from the increase amount comparison circuit 25. The second line current I ₂ does not decrease by a decrease amount ΔI ₂ (ΔI ₂ ≧ K ₂ ) greater than or equal to the second threshold value K _2, so that the low level output signal is still output from the decrease amount comparison circuit 26. Therefore, since the output signal of the _fourth AND circuit 234 remains at a low level, the first trip signal S ₁ is not generated.

When the third circuit breaker 4 ₃ is cut off at time t ₂ , the fault current flowing through the own line 1L increases, but the fault current flowing through the other line 2L decreases, so the first line current I ₁ increases. The second line current I ₂ decreases. Therefore, increment [Delta] I ₁ of the first line current I ₁ is the first threshold value K ₁ or more ([Delta] I ₁ ≧ K ₁₎ becomes and, decrease [Delta] I ₂ of the second line current I ₂ second threshold When K ₂ or more (ΔI ₂ ≧ K ₂ ), the high level output signal is output from the increase amount comparison circuit 25 and the decrease amount comparison circuit 26. Therefore, the output signal of the _fourth AND circuit 23 ₄ is low level. Become high level. At this time, if the high-level second contact signal S _C2 is input from the second circuit breaker 4 ₂ , the output signals of the third and fourth AND circuits 23 ₃ and 23 ₄ are both set to the high level. Therefore, the output signal of the _fifth AND circuit 235 changes from the low level to the high level.

As a result, since the output signal of the OR circuit 24 becomes high level, when the first FD relay output signal _SFD1 is high level, the output signal of the _sixth AND circuit 236 changes from low level to high level. The first trip signal S ₁ is output from the trip signal generation circuit 20 to the first circuit breaker 4 ₁ . The first trip signal S ₁ is output at time t ₃ when the relay determination time T _RY (50 ms) has elapsed from the time t ₂ in the first power supply terminal distance relay apparatus 10 ₁ from the trip signal generating circuit 20 The
As a result, the first circuit breaker 4 ₁ has a total time (100 ms) of the relay determination time T _RY and the circuit breaker breaking time T _CB (50 ms) in the first power supply end distance relay device 10 ₁ from time t ₂ . It is completely cut off at time t ₄ when it has passed. As a result, the first circuit breaker 4 ₁ is t ₆ compared to the case of the conventional first power supply end distance relay device 110 ₁ shown by the broken line in FIG. 3A (see FIG. 17B). -T ₄ = ST2- (T _RY + T _CB ) (= 400 ms−100 ms = 300 ms).

As described above, the trip signal generation circuit 20 of the first power supply end distance relay device 10 ₁ has the increase amount ΔI ₁ of the first line current I ₁ equal to or greater than the first threshold value K ₁ , and When the decrease ΔI ₂ of the second line current I ₂ is equal to or greater than the second threshold K ₂ and the second contact signal S _C2 is at the high level, the second line current I ₂ is installed on the opposite end side of the own line 1L. Since the third circuit breaker 4 ₃ is determined to have been interrupted due to a short circuit accident in its own line 1L and generates the _first trip signal S ₁ , the “third relay” as in the protective relay device described in Patent Document 1 above. breaker 4 ₃ is cut off, "no need to transfer the transfer signal from the first opposing end distance relay apparatus 120 ₁ to the first power supply terminal distance relay apparatus 10 ₁ shown the effect.

The second power supply end distance relay device 10 ₂ is configured in the same manner as the first power supply end distance relay device 10 ₁ , so that the second power supply end distance relay device 10 ₂ in the other line 2L When a short circuit accident occurs in two protection sections (two-stage operating range A2 of the second power supply end distance relay device 10 ₂ ), the second power supply end distance relay device 110 ₂ is compared with the second power supply end distance relay device 110 2. The circuit breaker 4 ₂ can be quickly disconnected by ST2- (T _RY + T _CB ).

In the above description, the third AND circuit 23 ₃ calculates the logical product of the second and third determination result output signals VD ₂ and VD ₃ output from the operation region determination circuit 21 and the fifth logical product. While taking a logical product of the third aND circuit 23 ₃ and the output signal from the output signal of the fourth aND circuit 23 ₄ of the circuit 23 _5, the operation region determination circuit 21 in the aND circuit 23 ₅ of the fifth third determination result output signal VD ₃ and may be taken only logical product of the fourth aND circuit 23 ₄ of the output signal of the output from.
In addition, the first and second power supply end distance relay devices 10 ₁ and 10 ₂ are individually configured, but may be configured integrally.

Next, a distance relay device according to a second embodiment of the present invention will be described with reference to FIGS.
The first opposing end distance relay apparatus 30 ₁ is a distance relay apparatus according to this embodiment, the third and fourth before and after interruption of the first circuit breaker 4 ₁ installed on the power supply end of the self-line 1L the line current I _3, upon detecting a short circuit occurs in the power supply end of the self-line 1L based on the amount of change I _4, a third trip signal S ₃ for blocking the third breaker 4 ₃ instantaneous 14 is different from the conventional first opposed end distance relay device 120 _{1 shown} in FIG.

That is, the first opposing end distance relay apparatus 30 ₁ shown in FIG. 4, the third third line current I ₃ of the increment [Delta] I ₃ a predetermined third threshold value input from the current transformer 3 ₃ K ₃ (for example, 120 mA when the minimum detectable value of the third line current I ₃ is 40 mA) and the fourth line current I input from the _fourth current transformer 3 _{4 4} of decrease [Delta] I ₄ is the fourth threshold value K ₄ of a predetermined (e.g., if the minimum detectable value of the fourth line current I ₄ is 40mA is 120 mA) or more, and, next to its own line 1L The fourth contact signal S _C4 input from the fourth circuit breaker 4 ₄ installed on the opposite end side of the other line 2L that is a line is at a high level (the fourth circuit breaker 4 ₄ is not cut off). it shows a.) the on condition to generate a third trip signal S ₃ instantaneously.

To achieve this, trip trip signal generating circuit 40 in which the first opposing end distance relay apparatus 30 ₁ is provided, as shown in FIG. 5, except for the following, as shown in FIG. 2 The configuration is the same as that of the signal generation circuit 20.

(1) The operation range determination circuit 41 calculates the third impedance Z ₃ (Z ₃ = Vb / I ₃ ) based on the opposite end bus voltage Vb and the third line current I _3, and then calculates the calculated first impedance Z ₃ (Z ₃ = Vb / I ₃ ). based on the third impedance Z ₃ determines a first operation region of the opposite end distance relay apparatus 30 _1.
(2) The increase amount comparison circuit 45 obtains an increase amount ΔI ₃ of the third line current I ₃ , and generates a high-level output signal when the obtained increase amount ΔI ₃ is equal to or greater than the third threshold value K _3. .
(3) The reduction amount comparison circuit 46 obtains a reduction amount ΔI ₄ of the fourth line current I ₄ , and generates a high-level output signal when the obtained reduction amount ΔI ₄ is equal to or greater than the fourth threshold value K _4. .
(4) fifth AND circuit 43 _5, a logical product of the third AND circuit 43 ₃ and the output signal from the fourth AND circuit 43 _fourth output signal and the fourth contact signal S _C4 .

Next, short circuit at the first opposing end distance relay apparatus 30 ₁ in the second guard interval in its own line 1L (first two-stage operation region A2 opposing end distance relay apparatus 30 ₁₎ shown in FIG. 4 The operation of the trip signal generation circuit 40 when this occurs will be described with reference to FIG.

When a short circuit accident occurs at time t ₀ shown in FIG. 6 in the second protection section, the trip signal generating circuit provided in the first power supply end distance relay device 110 ₁ installed on the power supply end side of the own line 1L. 220 (see FIG. 15) calculates a _first impedance Z ₁ (Z ₁ = Va / I ₁ ) based on the bus voltage Va and the first line current I ₁ , and sets the calculated first impedance Z ₁ to When the occurrence of a short circuit accident in the first stage operating area A1 of the first power supply end distance relay device 110 ₁ is detected based on the first trip signal S ₁ for breaking the _first circuit breaker 41, It occurs at time t ₁ after the relay determination time T _RY (50 ms) has elapsed in the power supply end distance relay device 110 ₁ . As a result, the first breaker 4 _1, as shown in FIG. 6, the relay determination time of the first power supply terminal distance relay apparatus 110 ₁ T _RY and breaker interruption time T _CB (50 ms) total time ( = 50 ms + 50 ms = 100 ms), and completely cut off at time t ₂ after elapse.

On the other hand, in the first opposite end distance relay device 30 ₁ installed on the opposite end side of the own line 1L, the trip occurs from the accident occurrence time t ₀ to the time t ₂ when the first circuit breaker 4 ₁ is completely cut off. operation region determination circuit 41 of the signal generating circuit 40, reactance X ₃ of the third impedance Z ₃ calculated on the basis of the opposite ends bus voltage Vb and the third line current I ₃ is higher than the first value B ₁ also becomes larger and the second value B ₁ below, a determination of "first operation region of the opposite end distance relay apparatus 30 ₁ is a two-stage operation region A2" (see FIG. 16), a high level The second determination result output signal VD ₂ is output. Further, since the third impedance Z ₃ is also included in the circle of FIG. 16, the operation region determination circuit 41 also outputs a high-level third determination result output signal VD ₃ . As a result, the output signal of the _third AND circuit 433 becomes high level.
However, if the second and fourth circuit breakers 4 ₂ and 4 ₄ installed on the power supply terminal and the opposite terminal side of the other line 2L are not interrupted, the first circuit breaker 4 is started from the accident occurrence time t ₀ . Until time t ₂ when ₁ is completely cut off, as shown in FIGS. 6A and 6B, the increase amount ΔI ₃ of the third line current I ₃ is smaller than the third threshold K ₃ ( ΔI ₃ <K ₃ ) and the decrease amount ΔI ₄ of the fourth line current I ₄ is smaller than the fourth threshold value K ₄ (ΔI ₄ <K ₄ ). Therefore, the increase amount comparison circuit 45 and the decrease amount comparison circuit. A low level output signal is output from 46. Therefore, since the output signal of the _fourth AND circuit 434 remains at a low level, the third trip signal S ₃ is not generated.
The absolute value of the fourth line current I ₄ is large, but it is large in the negative direction when positive in the case of flowing in the internal direction (direction from the opposite end bus to the bus). Therefore, suppose that it is decreasing.

When the first breaker 4 ₁ at time t ₂ is cut off, FIG. 6 (a), the (b), the increment [Delta] I ₃ of the third line current I ₃ is the third threshold value K ₃ The above is (ΔI ₃ ≧ K ₃ ), and the decrease amount ΔI ₄ of the fourth line current I ₄ is equal to or greater than the fourth threshold K ₄ (ΔI ₄ ≧ K ₄ ). As a result, high level output signals are output from the increase amount comparison circuit 45 and the decrease amount comparison circuit 46, so that the output signal of the _fourth AND circuit 434 changes from low level to high level. At this time, when the fourth contact signal S _C4 to the high level is input from the fourth breaker 4 _4, third and fourth AND circuit 43 _3, 43 ₄ of the output signal and both high-level Therefore, the output signal of the _fifth AND circuit 435 changes from the low level to the high level.

As a result, the output signal of the OR circuit 44 is at a high level. Therefore, if the second FD relay output signal _SFD2 input from the second failsafe FD relay (not shown) is at a high level, The output signal of the AND circuit 43 ₆ changes from low level to high level, and the third trip signal S ₃ is output from the trip signal generation circuit 40 to the third circuit breaker 4 ₃ . The third trip signal S ₃ of is output at time t ₃ when the relay determination time T _RY (50 ms) has elapsed from the time t ₂ in the first opposing end distance relay device 30 ₁ from the trip signal generating circuit 40 The
As a result, the third circuit breaker 4 ₃ has the total time (= 50 ms + 50 ms = the relay determination time T _RY and the circuit breaker breaking time T _CB (50 ms) in the first opposing end distance relay device 30 ₁ from time t ₂ . 100 ms) is completely blocked at a time t ₄ when has elapsed. As a result, the third circuit breaker 4 ₃ is t ₆ −t ₄ = ST 2 − (T) as compared with the case of the conventional first opposing end distance relay device 120 ₁ shown by a broken line in FIG. _RY + T _CB ) (= 400 ms−100 ms = 300 ms) can be shut off quickly.

As described above, the trip signal generation circuit 40 of the first opposing end distance relay device 30 ₁ has the increase amount ΔI ₃ of the third line current I ₃ equal to or greater than the third threshold value K ₃ , and When the reduction amount ΔI ₄ of the fourth line current I ₄ is equal to or greater than the fourth threshold K ₄ and the fourth contact signal S _C4 is at the high level, it is installed on the power supply end side of the own line 1L. In order to generate the _third trip signal S ₃ by determining that the first circuit breaker 4 ₁ is interrupted due to a short circuit accident in the own line 1L, the “first relay” described in the above-mentioned Patent Document 1 is “1st. It is not necessary to transfer a transfer signal indicating that the circuit breaker 4 ₁ has been cut off from the first power supply end distance relay device 110 ₁ to the first counter end distance relay device 30 ₁ .

The second opposing end distance relay device 30 ₂ is configured in the same manner as the first opposing end distance relay device 30 ₁ , so that the second opposing end distance relay device 30 ₂ in the other line 2L When a short circuit accident occurs in the two protection sections (two-stage operation area A2 of the second opposing end distance relay device 30 ₂ ), the fourth is compared with the conventional second opposing end distance relay device 120 ₂ . it can be blocked in the breaker 4 ₄ ST2- (T _RY + T _CB) as soon.

In the above description, the third AND circuit 43 ₃ calculates the logical product of the second and third determination result output signals VD ₂ and VD ₃ output from the operation range determination circuit 41 and the fifth logical product. While taking a logical product of the third aND circuit 43 ₃ and the output signal from the output signal of the fourth aND circuit 43 ₄ of the circuit 43 _5, the operation region determination circuit 41 in the aND circuit 43 ₅ of the fifth third determination result output signal VD ₃ and may be taken only logical product of the fourth aND circuit 43 ₄ of the output signal of the output from.
The first and second opposing end distance relay apparatus 30 _1, 30 ₂ have been individually configured, may be integrated.
Further, the first and second power supply end distance relay devices 10 ₁ and 10 ₂ shown in FIG. 1 and the first and second opposing end distance relay devices 30 ₁ and 30 ₂ shown in FIG. May be used.

Next, a distance relay device according to a third embodiment of the present invention will be described with reference to FIGS.
The first load end distance relay device 50 ₁ , which is a distance relay device according to the present embodiment, is a balanced three-terminal system having its own branch line 3L and other branch line 4L branched from its own line 1L and other line 2L. In a two-line power transmission line, it is installed on the load end side of its own branch line 3L.
The first load end distance relay device 50 ₁ includes a third breaker installed before or after the _first circuit breaker 41 installed on the power supply end side of the own line 1L or on the opposite end side of the own line 1L. Upon detection of the short circuit occurs in the power supply terminal side or the opposite end of its own line 1L based on the fifth and the variation of the line current I _5, I ₆ of the sixth before and after blocking of vessels 4 _3, of its own branch line 3L The conventional first power source shown in FIG. 14 is provided with a function of instantaneously generating a _fifth trip signal S ₅ for breaking the _fifth circuit breaker 45 installed on the load end side. It differs from the end distance relay apparatus 110 _1.

That is, the first load end distance relay device 50 ₁ shown in FIG. 7 has the fifth line current I ₅ input from the _fifth current transformer 3 ₅ installed on the load end side of the own branch line 3L. fifth threshold value K ₅ increment [Delta] I ₅ of the predetermined (e.g., if the minimum detectable value of the fifth line current I ₅ is 40mA is 120 mA) or more, and is branched from the other line 2L and other branch lines sixth sixth threshold K of decrease [Delta] I ₆ of the sixth line current I ₆ to be inputted from the current transformer 3 ₆ is in a predetermined installed at the load end side of the 4L ₆ (e.g., the 6 is 120 mA when the minimum detectable value of the line current I ₆ is 40 mA) and is installed on the load end side of the other branch line 4L which is the adjacent line of the own branch line 3L. contact signal S _C6 of the sixth is a high level is input from the breaker 4 ₆ (breaker 4 ₆ sixth is blocked Indicating no.) That the conditions, to generate a fifth trip signal S ₅ for blocking the circuit breaker 4 ₅ fifth instantly.

In order to realize this, the trip signal generating circuit 60 included in the first load end distance relay device 50 ₁ is configured as shown in FIG. 2 except for the following points as shown in FIG. The configuration is the same as that of the signal generation circuit 20.

(1) Operation area determination circuit 61, the load end of the bus (hereinafter referred to as "load end bus".) The fifth impedance Z ₅ on the basis of the line current I ₅ across the load bus voltage Vc and the fifth After calculating (Z ₅ = Vc / I ₅ ), the operating range of the first load end distance relay device 50 ₁ is determined based on the calculated fifth impedance Z ₅ .
(2) The increase amount comparison circuit 65 calculates the increase amount ΔI ₅ of the fifth line current I ₅ , and generates a high-level output signal when the calculated increase amount ΔI ₅ is equal to or greater than the fifth threshold value K _5. .
(3) The reduction amount comparison circuit 66 obtains a reduction amount ΔI ₆ of the sixth line current I ₆ , and generates a high level output signal when the obtained reduction amount ΔI ₆ is equal to or greater than the sixth threshold value K _6. .
(4) fifth AND circuit 63 _5, a logical product of the contact signal S _C6 of the output signal of the third AND circuit 63 ₃ and the output signal from the fourth AND circuit 63 ₄ and the sixth .

Next, short circuit at the first power supply terminal distance relay apparatus 110 ₁ of the second protection section (the first second-stage operation region A2 of the power supply end distance relay apparatus 110 ₁₎ in its own line 1L shown in FIG. 7 The operation of the trip signal generation circuit 60 in the case of occurrence of this will be described with reference to FIG.

When a short circuit accident occurs at time t ₀ shown in FIG. 9 in the second protection section, the trip signal generating circuit provided in the first opposite end distance relay device 120 ₁ installed on the opposite end side of the own line 1L. the third impedance Z ₃ based on the opposite end bus voltage Vb and the third line current _{I 3 (Z 3 = Vb /} I 3) is calculated, and third, based on the third impedance Z ₃ calculated When the occurrence of a short circuit accident in the one-stage operation area A1 of the opposite end distance relay device 120 ₁ is detected, a third trip signal S ₃ for breaking the third breaker 4 ₃ is sent to the first opposite end distance relay. It occurs at time t ₁ after elapse of the relay determination time T _RY (50 ms) in the electric device 120 ₁ . As a result, the third circuit breakers 4 ₃ of the relay determination time in the first opposing end distance relay apparatus 120 ₁ T _RY and breaker interruption time T _CB (50 ms) total time (= 50ms + 50ms = 100ms) after It is completely blocked in the time t _2.

On the other hand, in the first load end distance relay device 50 ₁ installed on the load end side of the own branch line 3L, from the accident occurrence time t ₀ to the time t ₂ when the third circuit breaker 4 ₃ is completely cut off. The operating range determination circuit 61 of the trip signal generation circuit 60 uses the reactance component X ₅ of the _fifth impedance Z ₅ calculated based on the load end bus voltage Vc and the fifth line current I ₅ as the first value B _1. Greater than the second value B _{1 and} below, it is determined that “the operating range of the first load end distance relay device 50 ₁ is the two-stage operating range A2” (see FIG. 16). The level second determination result output signal VD ₂ is output. In addition, since the fifth impedance Z ₅ is also included in the circle of FIG. 16, the operating range determination circuit 61 also outputs a high-level third determination result output signal VD ₃ . As a result, the output signal of the _third AND circuit 633 becomes high level.
However, when an accident occurs, the accident current does not bypass the own branch line 3L and the other branch line 4L. Therefore, the fifth and sixth line currents I ₅ and I ₆ flowing through the own branch line 3L and the other branch line 4L are shown in FIG. As shown in a) and (b), neither increases nor decreases. Accordingly, a low level output signal remains output from the increase amount comparison circuit 65 and the decrease amount comparison circuit 66. Therefore, since the output signal of the _fourth AND circuit 634 remains at the low level, the fifth trip signal S ₅ is not generated.

When the third circuit breaker 4 ₃ is completely cut off at the time t ₂ , the fault current flowing in the other line 2L flows around the other branch line 4L and the own branch line 3L. As shown in b), the fifth line current I ₅ increases and the sixth line current I ₆ decreases. Therefore, the increase amount ΔI ₅ of the fifth line current I ₅ is greater than or equal to the _fifth threshold value K ₅ (ΔI ₅ ≧ K ₅ ), and the decrease amount ΔI ₄ of the sixth line current I ₆ is the sixth value. If the threshold value is K ₆ or more (ΔI ₆ ≧ K ₆ ), the output signals of the increase amount comparison circuit 65 and the decrease amount comparison circuit 66 change from the low level to the high level, so that the output signal of the _fourth AND circuit 634 is From low level to high level. At this time, the sixth contact signal S _C6 of the high level is inputted from the circuit breaker 4 ₆ sixth, third and fourth AND circuit 63 _3, 63 ₄ of the output signal of the both at a high level Therefore, the output signal of the _fifth AND circuit 635 changes from the low level to the high level.
Although the absolute value of the sixth line current I ₆ is large, if the case of flowing in the internal direction (direction from the load end bus toward the own line 1L) is positive, the sixth line current I ₆ increases in the negative direction. Suppose that it is decreasing.

As a result, the output signal of the OR circuit 64 is at a high level. Therefore, if the third FD relay output signal S _FD3 input from the third fail-safe FD relay (not shown) is at a high level, since the logic output signal of the aND circuit 63 ₆ 6 becomes a high level from a low level, a trip signal S ₅ of the fifth is output from the trip signal generating circuit 60 to the breaker 4 ₅ fifth. Incidentally, the fifth trip signal S ₅ of is output at time t ₃ when the relay determination time T _RY (50 ms) has elapsed from the time t ₂ in the first load end distance relay device 50 ₁ from the trip signal generating circuit 60 The
Thus, the fifth circuit breaker 4 _5, completely blocked from time t ₂ to total time time t ₄ when (= 50ms + 50ms = 100ms) has elapsed the relay determination time T _RY and breaker interruption time T _CB (50 ms) Is done. As a result, as compared with the first load end distance relay apparatus prior art shown by dashed lines in FIG. 9 (a), the breaker 4 ₅ of the _{5 t 6 -t 4 = ST2- (} T RY + T _CB )) (eg, 400 ms-100 ms = 300 ms) can be interrupted earlier.

Incidentally, the short circuit at the first opposing end distance relay apparatus 120 ₁ of the second protection section (the first second-stage operation region A2 opposing end distance relay apparatus 120 ₁₎ in its own line 1L shown in FIG. 7 in the event of even, in the same manner, a fifth circuit breaker 4 ₅ as compared with the conventional first load end distance relay device _{t 6 -t 4 = ST2- (T} RY + T CB) as soon Can be blocked.
Further, the second load end distance relay device 50 ₂ is also configured in the same manner as the first load end distance relay device 50 ₁ , so that the second power end distance relay device 110 ₂ in the other line 2L 2 of the guard interval (second power supply terminal distance relay apparatus 110 ₂ for two-stage operation region A2) in short-circuit accident the case and the second in the other line 2L facing end distance relay apparatus 120 ₂ of the second generation If the short-circuit failure occurs in the protection zone (second opposing end distance relay apparatus 120 ₂ for two-stage operation region A2), the sixth circuit breaker 4 as compared with the conventional second load end distance relay device ₆ can be cut off as early as ST2- (T _RY + T _CB ).

In the above description, the third AND circuit 63 ₃ calculates the logical product of the second and third determination result output signals VD ₂ and VD ₃ output from the operation region determination circuit 61 and the fifth logical product. While taking a logical product of the third aND circuit 63 ₃ and the output signal from the output signal of the fourth aND circuit 63 ₄ of the circuit 63 _5, the operation region determination circuit 61 in the aND circuit 63 ₅ of the fifth third determination result output signal VD ₃ and may be taken only logical product of the fourth aND circuit 63 ₄ of the output signal of the output from.
Further, ₁ the first and second load end distance relay device 50, 50 ₂ have been individually configured, may be integrated.

Next, the first and second power supply end distance relay devices 10 ₁ and 10 ₂ shown in FIG. 1 and the first and second opposing end distance relay devices 30 ₁ and 30 ₂ shown in FIG. Referring to FIGS. 10 to 13, the operation of trip signal generating circuits 20, 40, 60 when the first and second load end distance relay devices 50 ₁ , 50 ₂ shown in FIG. explain.

First, when the short-circuit fault in the first power supply terminal distance relay apparatus 10 ₁ in the second guard interval in its own line 1L (first two-stage operation region A2 of the power supply end distance relay apparatus 10 ₁₎ has occurred The operation of trip signal generating circuits 20, 40, 60 will be described with reference to FIG.
When a short circuit accident occurs at time t ₀ shown in FIG. 10 in the second protection section, the trip signal generation circuit 40 (see FIG. 5) included in the first opposing end distance relay device 30 ₁ Based on the third impedance Z ₃ calculated based on the voltage Vb and the third line current I ₃ , the occurrence of a short-circuit accident in the first stage operating range A1 of the first opposing end distance relay device 30 ₁ is detected. A third trip signal S ₃ for breaking the third circuit breaker 4 ₃ is generated at time t ₁ after elapse of the relay determination time T _RY (50 ms) in the first counter end distance relay device 30 ₁ . As a result, the third circuit breakers 4 ₃ of the relay determination time in the first opposing end distance relay apparatus 30 ₁ T _RY and breaker interruption time T _CB (50 ms) total time (= 50ms + 50ms = 100ms) after It is completely blocked in the time t _2.

When the third circuit breaker 4 ₃ is completely cut off, as shown in FIGS. 10A and 10B, the first line current I ₁ increases and the second line current I ₂ decreases. Therefore, increment [Delta] I ₁ of the first line current I ₁ is a first threshold value K ₁ or more ([Delta] I ₁ ≧ K _1), and, decrease [Delta] I ₂ of the second line current I ₂ of the second If it is the threshold value K ₂ or more ([Delta] I ₂ ≧ K _2), trip signal generating circuit 20 (see FIG. 2) increase the comparator circuit 25 and a decrease amount comparison circuit of the first power supply terminal distance relay apparatus 10 ₁ is provided since the high-level output signal from 26 is output, the output signal of the fourth aND circuit 23 ₄ becomes high level from a low level. At this time, if the high-level second contact signal S _C2 is input from the second circuit breaker 4 ₂ , the output signals of the third and fourth AND circuits 23 ₃ and 23 ₄ are both set to the high level. Therefore, the output signal of the _fifth AND circuit 235 changes from the low level to the high level.

As a result, since the output signal of the logical sum circuit 24 becomes high level, when the first FD relay output signal _SFD1 is high level, the output signal of the _sixth logical product circuit 236 changes from low level to high level. since, first trip signal S ₁ is output from the trip signal generating circuit 20 to the first breaker 4 _1. The first trip signals S _1, the relay determination time T _RY from the time t ₂ in the first power supply terminal distance relay apparatus 10 ₁ (= 50 ms) output from the trip signal generating circuit 20 at time t ₃ when has elapsed Is done.
Thus, the first breaker 4 _1, from time t ₂ relay determination time T _RY and breaker interruption time T _CB (= 50ms) total time (= 100 ms) completely blocked the time t ₄ when the elapsed The As a result, the first circuit breaker 4 ₁ is t ₆ compared to the case of the conventional first power supply end distance relay device 110 ₁ shown by the broken line in FIG. 10A (see FIG. 17B). -T ₄ = ST2- (T _RY + T _CB ) (= 400 ms−100 ms = 300 ms).

When the third circuit breaker 4 ₃ is completely cut off, as shown in FIGS. 10E and 10F, the fifth line current I ₅ increases and the sixth line current I ₆ decreases. To do. Therefore, increase [Delta] I ₅ of the fifth line current I ₅ is a fifth threshold value K ₅ or more ([Delta] I ₅ ≧ K _5), and decreases the amount [Delta] I ₆ of the line current I ₆ of the sixth of the sixth When the threshold value is K ₆ or more (ΔI ₆ ≧ K ₆ ), the increase amount comparison circuit 65 and the decrease amount comparison circuit of the trip signal generation circuit 60 (see FIG. 8) included in the first load end distance relay device 50 ₁ are provided. since the high-level output signal from 66 is output, the output signal of the fourth aND circuit 63 ₄ becomes high level from a low level. At this time, the sixth contact signal S _C6 of the high level is inputted from the circuit breaker 4 ₆ sixth, third and fourth AND circuit 63 _3, 63 ₄ of the output signal of the both at a high level Therefore, the output signal of the _fifth AND circuit 635 changes from the low level to the high level.

As a result, since the output signal of the logical sum circuit 64 becomes high level, if the third FD relay output signal _SFD3 is high level, the output signal of the _sixth logical product circuit 636 changes from low level to high level. since, trip signal S ₅ of the fifth is outputted from the trip signal generating circuit 60 to the breaker 4 ₅ fifth. Incidentally, the fifth trip signal S ₅ of the relay determination time T _RY from the time t ₂ in the first load end distance relay apparatus 50 ₁ (= 50 ms) output from the trip signal generating circuit 60 at time t ₃ when has elapsed Is done.
Thus, the fifth circuit breaker 4 _5, from time t ₂ relay determination time T _RY and breaker interruption time T _CB (= 50ms) total time (= 100 ms) completely blocked the time t ₄ when the elapsed The As a result, as compared with the first load end distance relay apparatus prior art shown by the broken line in FIG. 10 (e), the breaker 4 ₅ of the _{5 t 6 -t 4 = ST2- (} T RY + T _CB )) (= 400 ms-100 ms = 300 ms) can be interrupted as soon as possible.

It should be noted that the increase amount ΔI ₁ of the first line current I ₁ is smaller than the first threshold value K ₁ (ΔI ₁ <K ₁ ) when the third circuit breaker 4 ₃ is cut off due to the power system configuration condition, and the second When the decrease amount ΔI ₂ of the line current I ₂ is smaller than the second threshold K ₂ (ΔI ₂ <K ₂ ), the first circuit breaker 4 ₁ is not cut off as shown in FIGS. but FIG. 11 (e), the the order breaker 4 ₅ 5 as shown in (f) is completely shut off at time t _4, the first time t ₄ by a power supply terminal distance relay apparatus 10 ₁ The first circuit breaker 4 ₁ is completely cut off at time t _4b when the relay determination time T _RY and the circuit breaker cut-off time T _CB total time (= 100 ms) of the first power supply distance relay device 10 ₁ have elapsed. . As a result, even in such a case, the first circuit breaker 4 ₁ is t ₆ −t _4b = ST 2-2 (T _RY + T _CB ) as compared with the case of the conventional first power supply end distance relay device 110 _1. (= 400 ms−2 × 100 ms = 200 ms) can be shut off quickly.

Next, when the short circuit in the first opposing end distance relay apparatus 30 ₁ in the second guard interval in its own line 1L (first two-stage operation region A2 opposing end distance relay apparatus 30 ₁₎ has occurred The operation of the trip signal generating circuits 20, 40, 60 will be described with reference to FIG.
When a short circuit accident occurs at time t ₀ shown in FIG. 12 in the second protection section, the trip signal generation circuit 20 (see FIG. 2) provided in the first power supply end distance relay device 10 ₁ is connected to the bus voltage Va. and detecting a short circuit generated in the first line current I first-stage operation zone A1 of the power supply end distance relay apparatus 10 ₁ based on the first impedance Z ₁ calculated based on the _1, the first The first trip signal S ₁ for breaking the circuit breaker 4 ₁ is generated at time t ₁ after the relay determination time T _RY (50 ms) in the first power supply end distance relay device 10 ₁ has elapsed. As a result, the first breaker 4 _1, first relay determination time in the power supply terminal distance relay apparatus 10 ₁ T _RY and breaker interruption time T _CB (50 ms) total time (= 50ms + 50ms = 100ms) after It is completely blocked in the time t _2.

When the first circuit breaker 4 ₁ is completely cut off, as shown in FIGS. 12C and 12D, the third line current I ₃ increases and the fourth line current I ₄ decreases. Therefore, increase [Delta] I ₃ of the third line current I ₃ is the third threshold value K ₃ or more ([Delta] I ₃ ≧ K _3), and decreases the amount [Delta] I ₄ of the fourth line current I ₄ is the fourth If it is the threshold value K ₄ above (ΔI ₄ ≧ K _4), the first increment comparator circuit 45 and a decrease amount comparison circuit of the trip signal generating circuit 40 to the opposite end distance relay device 30 ₁ comprises (see Figure 5) since the high-level output signal from 46 is output, the output signal of the fourth aND circuit 43 ₄ becomes high level from a low level. At this time, when the fourth contact signal S _C4 to the high level is input from the fourth breaker 4 _4, third and fourth AND circuit 43 _3, 43 ₄ of the output signal and both high-level Therefore, the output signal of the _fifth AND circuit 435 changes from the low level to the high level.

As a result, since the output signal of the logical sum circuit 44 becomes high level, if the second FD relay output signal _SFD2 is high level, the output signal of the _sixth logical product circuit 436 changes from low level to high level. Therefore, the third trip signal S ₃ is output from the trip signal generation circuit 40 to the third circuit breaker 4 ₃ . The third trip signal S ₃ of the relay determination time T _RY from the time t ₂ in the first opposing end distance relay apparatus 30 ₁ (= 50 ms) output from the trip signal generating circuit 40 at time t ₃ when has elapsed Is done.
Thus, the third circuit breakers 4 ₃ from time t ₂ relay determination time T _RY and breaker interruption time T _CB (= 50ms) total time (= 100 ms) completely blocked the time t ₄ when the elapsed The As a result, the third circuit breaker 4 ₃ is t ₆ −t ₄ = ST 2 − (T) as compared with the case of the conventional first opposing end distance relay device 120 ₁ shown by a broken line in FIG. _RY + T _CB ) (= 400 ms−100 ms = 300 ms) can be shut off quickly.

Further, when the first breaker 4 ₁ is completely cut off, as shown in FIG. 12 (e), (f) , the line current I ₆ of the sixth line current I ₅ of the fifth increase decrease To do. Therefore, increase [Delta] I ₅ of the fifth line current I ₅ is a fifth threshold value K ₅ or more ([Delta] I ₅ ≧ K _5), and decreases the amount [Delta] I ₆ of the line current I ₆ of the sixth of the sixth When the threshold value is K ₆ or more (ΔI ₆ ≧ K ₆ ), the increase amount comparison circuit 65 and the decrease amount comparison circuit of the trip signal generation circuit 60 (see FIG. 8) included in the first load end distance relay device 50 ₁ are provided. since the high-level output signal from 66 is output, the output signal of the fourth aND circuit 63 ₄ becomes high level from a low level. At this time, the sixth contact signal S _C6 of the high level is inputted from the circuit breaker 4 ₆ sixth, third and fourth AND circuit 63 _3, 63 ₄ of the output signal of the both at a high level Therefore, the output signal of the _fifth AND circuit 635 changes from the low level to the high level.

As a result, since the output signal of the logical sum circuit 64 becomes high level, if the third FD relay output signal _SFD3 is high level, the output signal of the _sixth logical product circuit 636 changes from low level to high level. since, trip signal S ₅ of the fifth is output from the trip signal generating circuit 60 to the breaker 4 ₅ fifth. Incidentally, the fifth trip signal S ₅ of the relay determination time T _RY from the time t ₂ in the first load end distance relay apparatus 50 ₁ (= 50 ms) output from the trip signal generating circuit 60 at time t ₃ when has elapsed Is done.
Thus, the fifth circuit breaker 4 _5, from time t ₂ relay determination time T _RY and breaker interruption time T _CB (= 50ms) total time (= 100 ms) completely blocked the time t ₄ when the elapsed The As a result, 12 than that of the first load end distance relay apparatus prior art shown by the broken line in (e), the breaker 4 ₅ of the _{5 t 6 -t 4 = ST2- (} T RY + T _CB )) (= 400 ms-100 ms = 300 ms) can be interrupted as soon as possible.

Note that the increase amount ΔI ₃ of the third line current I ₃ is smaller than the third threshold K ₃ (ΔI ₃ <K ₁ ) when the _first circuit breaker 41 is cut off due to the power system configuration condition, and the fourth When the decrease amount ΔI ₄ of the line current I ₄ is smaller than the fourth threshold K ₄ (ΔI ₄ <K ₄ ), the third circuit breaker 4 ₃ is not cut off as shown in FIGS. but FIG. 13 (e), from the time t ₄ by for breaker 4 ₅ 5 is completely shut off at time t ₄ (f), the first opposing end distance relay apparatus 30 ₁ third circuit breakers 4 ₃ is completely blocked in the first opposing end distance relay apparatus 30 ₁ in the relay determination time T _RY and breaker interruption time T _CB total time (= 100 ms) time t _4b has passed . As a result, even in such a case, the third circuit breaker 4 ₃ is t ₆ −t _4b = ST2-2 (T _RY + T _CB ) as compared with the case of the conventional first opposing end distance relay device 120 _1. (= 400 ms−2 × 100 ms = 200 ms) can be shut off quickly.

The it has been described when there is no load current, first the power supply terminal distance relay apparatus 10 ₁ shown in FIG. 1, depending on the conditions such as system configuration and load currents, first power in its own line 1L or than the time t ₄ when the short circuit at the end distance relay apparatus 10 ₁ of the second protection section (the first second-stage operation region A2 of the power supply end distance relay apparatus 10 ₁₎ shown in FIG. 3 in the event of can block the first breaker 4 ₁ earlier.
For example, as shown in FIG. 18, when the load current flows from the bus to the opposite end bus on the own line 1L and the other line 2L before the occurrence of the short circuit accident, the first power supply end distance relay device on the own line 1L 10 increment [Delta] I ₁ of the first of a short-circuit accident in _one of the second guard interval occurs in the line current I ₁ is the reduction amount [Delta] I ₂ of the first threshold value K ₁ or more and becomes and second line current I ₂ When the second threshold value K ₂ or more is reached, the first trip signal S ₁ from the trip signal generation circuit 20 shown in FIG. 2 is determined as the relay determination of the first power supply distance relay device 10 ₁ from the accident occurrence time t ₀ . It is output at time t ₁ when time T _RY (50 ms) has elapsed. Thereby, the first circuit breaker 4 ₁ is completely cut off at time t ₂ when the circuit breaker breaking time T _{CB has} elapsed from time t ₁ . As a result, it is possible to cut off the _{t 4 -t 2 = T RY +} T CB (= 50ms + 50ms = 100ms) as soon the first breaker 4 ₁ than when there is no load current shown in FIG.

Moreover, in the 1st opposing end distance relay apparatus 30 ₁ shown in FIG. 4, if load current is small, the 2nd protection area (1st 1st opposing end distance relay apparatus 30 ₁ in the own line 1L will be demonstrated. it can be opposed end distance relay apparatus 30 ₁ of the short-circuit accident in two stages operating region A2) of shutting off the third breaker 4 ₃ earlier than the time t ₄ when shown in FIG. 6 in the event of.
For example, as shown in FIG. 19, when a small load current is flowing from the bus to the opposite end bus in the own line 1L and the other line 2L before the occurrence of the short circuit accident, the first opposite end distance relay in the own line 1L is performed. a short circuit accident occurs in the second guard interval of the device 30 ₁ third line current I ₃ of the increment [Delta] I ₃ is the third threshold value K ₃ or more and becomes and decrease [Delta] I ₄ of the fourth line current I ₄ When There will fourth threshold value K ₄ or more, the trip signal generating circuit 40 from the third trip signal S ₃ shown in FIG. 5, the accident occurrence time t ₀ a first opposing end distance relay apparatus 30 ₁ of the relay It is output at time t ₁ when the determination time T _RY (50 ms) has elapsed. As a result, the third circuit breaker 4 ₃ is completely disconnected at time t ₂ when the circuit breaker interruption time T _{CB has} elapsed from time t ₁ . As a result, it is possible to cut off the _{t 4 -t 2 = T RY +} T CB (= 50ms + 50ms = 100ms) as soon third breaker 4 ₃ than when there is no load current shown in FIG.

The first and second power supply end distance relay devices 10 ₁ , 10 ₂ and the first and second opposing end distance relay devices 30 ₁ , 20 ₂ and the first and second load end distance relays described above. In the devices 50 ₁ and 50 ₂ , the change amount ΔVb of the bus voltage Va, the change amount ΔVb of the opposite-end bus voltage Vb, or the load end, when applicable depending on conditions such as the rear power supply capacity, the configuration and impedance of the transmission line It may be added as a condition that the change amount ΔVc of the bus voltage Vc is equal to or greater than a predetermined seventh threshold value K ₇ . Here, the seventh threshold value K ₇ may be set in consideration of a change in arc resistance when the accident continues, a voltage variation due to a change in accident phenomenon, and is set to 5 V, for example.
In this case, for example, the trip signal generation circuit 20 shown in FIG. 2 includes a change amount comparison circuit that generates a high-level output signal when the change amount ΔVa of the bus voltage Va is equal to or greater than the seventh threshold K _7. In addition, in the fifth AND circuit 23 ₅ , the output signal of the change amount comparison circuit, the output signal of the third AND circuit 23 ₃ , the output signal of the fourth AND circuit 23 ₄ , and the second contact point A logical product with the signal S _C2 may be taken.

The first to sixth threshold values K _{1 to} K ₆ are 120 mA (three times) when the minimum detectable value of the _{first to fourth} line currents I _{1 to} I ₄ is 40 mA. The value may be three times or more the minimum detectable value of the _{first to fourth} line currents I _{1 to} I ₄ according to the power source capacity, the configuration / impedance of the transmission line, and the current transformation ratio (CT ratio).
Further, the delay circuits such as the first and second delay circuits 22 ₁ and 22 ₂ shown in FIG. 2 may be configured by a circuit that delays the input signal by a predetermined time, or the input signal is inputted. And a timer that outputs an output signal after counting a predetermined number of times.

It is a diagram for explaining a first power supply terminal distance relay apparatus 10 ₁ is a distance relay apparatus according to a first embodiment of the present invention. Figure 1 a first power supply terminal distance relay apparatus 10 ₁ shown in FIG. 5 is a diagram showing a configuration of a trip signal generation circuit 20 that comprises. FIG. 3 is a diagram for explaining an operation of a trip signal generation circuit 20 shown in FIG. 2. It is a diagram for explaining a first opposing end distance relay apparatus 30 ₁ is a distance relay apparatus according to a second embodiment of the present invention. Figure 4 first opposing end distance relay apparatus 30 ₁ shown in FIG. 5 is a diagram showing a configuration of a trip signal generation circuit 40 that comprises. It is a figure for demonstrating operation | movement of the trip signal generation circuit 40 shown in FIG. It is a diagram for explaining a third first load end distance relay apparatus 50 ₁ is a distance relay apparatus according to an embodiment of the present invention. It is a figure which shows the structure of the trip signal generation circuit 60 with which the 1st load end distance relay apparatus 50 ₁ shown in FIG. 7 is provided. FIG. 9 is a diagram for explaining an operation of a trip signal generation circuit 60 shown in FIG. 8. The first and second power supply end distance relay devices 10 ₁ and 10 ₂ shown in FIG. 1 and the first and second opposed end distance relay devices 30 ₁ and 30 ₂ shown in FIG. 4 and shown in FIG. It is a figure for demonstrating operation | movement of the trip signal generation circuits 20, 40, 60 when the 1st and 2nd load end distance relay devices 50 ₁ and 50 ₂ are used simultaneously. The first and second power supply end distance relay devices 10 ₁ and 10 ₂ shown in FIG. 1 and the first and second opposed end distance relay devices 30 ₁ and 30 ₂ shown in FIG. 4 and shown in FIG. It is a figure for demonstrating operation | movement of the trip signal generation circuits 20, 40, 60 when the 1st and 2nd load end distance relay devices 50 ₁ and 50 ₂ are used simultaneously. The first and second power supply end distance relay devices 10 ₁ and 10 ₂ shown in FIG. 1 and the first and second opposed end distance relay devices 30 ₁ and 30 ₂ shown in FIG. 4 and shown in FIG. It is a figure for demonstrating operation | movement of the trip signal generation circuits 20, 40, 60 when the 1st and 2nd load end distance relay devices 50 ₁ and 50 ₂ are used simultaneously. The first and second power supply end distance relay devices 10 ₁ and 10 ₂ shown in FIG. 1 and the first and second opposed end distance relay devices 30 ₁ and 30 ₂ shown in FIG. 4 and shown in FIG. It is a figure for demonstrating operation | movement of the trip signal generation circuits 20, 40, 60 when the 1st and 2nd load end distance relay devices 50 ₁ and 50 ₂ are used simultaneously. It is a figure for demonstrating operation | movement of the distance relay apparatus used in a 3 step | paragraph distance relay system. The first opposing end distance relay apparatus 120 ₁ shown in FIG. 14 illustrates a configuration of trip signal generating circuit 220 that comprises. FIG. 16 is a diagram for explaining an operation of a trip signal generation circuit 220 shown in FIG. 15. FIG. 16 is a diagram for explaining an operation of a trip signal generation circuit 220 shown in FIG. 15. Is a first diagram for explaining the operation of the power supply end distance relay apparatus 10 ₁ shown in FIG. 1 when there is a load current. It is a diagram for explaining the first opposing end distance relay apparatus 30 ₁ of operation shown in FIG. 4 when a small load current.

Explanation of symbols

1 power 2 ₁ to 2 ₃ breaker 10 ₁ of the first to third transformer 3 ₁ to 3 ₆ current transformer of the first to sixth 41 _{to 6} first to sixth, 10 _2, 110 ₁ , 110 ₂ First and second power supply end distance relay devices 20, 40, 60, 220 Trip signal generation circuits 21, 41, 61, 221 Operating area determination circuits 22 ₁ , 22 ₂ , 42 ₁ , 42 ₂ , 62 _1, 62 _2, 222 _1, 222 ₂ first and second delay circuits 23 ₁ to 23 _6, 43 ₁ to 43 _6, 63 ₁ to 63 ₆ first to sixth aND circuit 24,44,64 for, 224 OR circuit 25, 45, 65 Increase amount comparison circuit 26, 46, 66 Decrease amount comparison circuit 30 ₁ , 30 ₂ , 120 ₁ , 120 ₂ First and second opposing end distance relay devices 50 ₁ , 50 ₂ First and second load end distance relay devices 223 _{1 to} 223 ₃ First to third AND circuits 1L Line 2L Other line 3L Self-divided line 4L Other branch lines A1 to A3 1st stage to 3rd stage operation area Va Bus voltage Vb Opposite end bus voltage Vc Load end bus voltage ΔVa, ΔVb, ΔVc Changes I _{1 to} I ₆ Sixth line currents ΔI ₁ , ΔI ₃ , ΔI ₅ increase amounts ΔI ₂ , ΔI ₄ , ΔI ₆ decrease amounts Z _{1 to} Z ₆ first to sixth impedances R _{1 to} R ₆ resistances X _{1 to} X ₆ reactances Minutes B ₁ and B ₂ First and second values K _{1 to} K ₇ First to seventh threshold values ST 1 to ST 3 First to third timed cooperative times VD _{1 to} VD ₄ First to fourth determination results Output signals S _{1 to} S ₆ First to sixth trip signals S _{FD1 to} S _FD3 First to third FD relay output signals S _{C1 to} S _C6 First to sixth contact signals t _{0 to} t ₆ , t _4a , t _4b Time _RY relay judgment time T _CB breaker break time P1, P2 points

Claims (9)

At the power supply end side or opposite end of the own line of the balanced two-line power transmission line composed of the own line (1L) and the other line (2L) laid between the power supply end side bus line and the opposite end side opposite end bus line Or a distance relay installed on the load end side of the self-branch line of a balanced two-line power transmission line further including the self-branch line (3L) and the other branch line (4L) branched from the own line and the other line An electrical device (10 ₁ ; 30 ₁ ; 50 ₁ ),
When the occurrence of an accident in the own line or the own branch line is detected, a trip signal (S ₁ ; S ₁ ; for breaking the circuit breaker (4 ₁ ; 4 ₃ ; 4 ₅ ) provided in the own line or the own branch line is detected. A trip signal generating circuit (20; 40; 60) for generating S ₃ ; S ₅ ),
The trip signal generation circuit has its own line current (I ₁ ; I ₃ ; I ₅ ) flowing through the own line or the own branch line and other line current (I ₂ ; I ₄ ) flowing through the other line or the other branch line. A trip signal generating means for instantaneously generating the trip signal when the occurrence of an accident on the power source end side or the opposite end side of the own line is detected based on a change amount of I ₆ );
A distance relay device characterized by that. In the trip signal generating means, the adjacent line circuit breakers (4 ₂ ; 4 ₄ ; 4 ₆ ) installed on the power supply end side or the opposite end side of the other line or the load end side of the other branch line are not interrupted. If the occurrence of an accident on the power source end side or the opposite end side of the own line is detected based on the change amount of the own line current and the other line current, the trip signal is generated instantaneously. The distance relay device according to claim 1. The trip signal generating means has an increase amount (ΔI ₁ ; ΔI ₃ ; ΔI ₅ ) of the own line current equal to or greater than a predetermined threshold (K ₁ ; K ₃ ; K ₅ ), and a decrease in the other line current. On the condition that the amount (ΔI ₂ ; ΔI ₄ ; ΔI ₆ ) is equal to or greater than a predetermined threshold value (K ₂ ; K ₄ ; K ₆ ), it is based on the change amount of the own line current and the other line current. The distance relay device according to claim 1 or 2, wherein the trip signal is instantaneously generated when an accident occurrence on the power supply end side or the opposite end side of the own line is detected.   The distance relay device according to claim 3, wherein the threshold value and the other threshold value are set to a value that is at least three times the minimum detectable value of the own line current and the other line current. Change amount (ΔVa) of bus voltage (Va) of the bus, change amount (ΔVb) of opposite end bus voltage (Vb) of the opposite end bus, or load end bus voltage (Vc) of the load end bus on the load end side 5. The distance relay device according to claim 3, wherein the trip signal is instantaneously generated on the condition that a change amount (ΔVc) of A is greater than or equal to another predetermined threshold value (K ₇ ). The trip signal generating means is configured such that when the increase amount of the own line current is equal to or greater than the threshold value and the decrease amount of the other line current is equal to or more than the other threshold value, 6. The trip signal is generated instantaneously by judging that another circuit breaker (4 ₁ ; 4 ₃ ) installed on the end side is interrupted by an accident in the own line. The distance relay device according to the above. The trip signal generating means is
An increase amount comparison circuit (25; 45; 65) for obtaining an increase amount of the own line current and generating an output signal when the obtained increase amount is equal to or greater than the threshold;
A reduction amount comparison circuit (26; 46; 66) for obtaining a reduction amount of the other line current and generating an output signal when the obtained reduction amount is equal to or greater than the other threshold;
A logical product circuit (23 ₄ ; 43 ₄ ; 63 ₄ ) that takes the logical product of the output signal of the increase amount comparison circuit and the output signal of the decrease amount comparison circuit;
The distance relay device according to claim 3, comprising: The trip signal generating means is another logical product circuit (23 ₅ ) that takes the logical product of the output signal of the logical product circuit and the contact signal (S _C2 ; S _C4 ; S _C6 ) input from the adjacent circuit breaker. The distance relay device according to claim 7, further comprising: 43 ₅ ; 63 ₅ ). Other distance relay devices (10 ₂ ; 30 ₂ ; 50 ₂ ) installed on the power supply terminal side or the opposite end side of the other line or the load end side of the other branch line have the same configuration as the distance relay apparatus. The distance relay device according to claim 1, wherein the distance relay device is integrally formed.

Images