JP2010166778A - Directional protective relay device and directional power relay device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a directional protective relay device and a directional power relay device, capable of reducing the installation number of current transformers for protecting a three-phase AC circuit against a short-circuit faults or reverse flows, as well as, the numbers of directional protective relays and directional power relays. <P>SOLUTION: An R-phase and an S-phase of a power transmission line are led through in the same direction, in an annular iron core of a two-phase through current transformer 10 installed on the power transmission line, wherein the R-phase is led through only once and the S-phase is led through two times. Upon detecting a short-circuit fault based on a short-circuit current I<SB>Ry</SB>inputted from the two-phase through current transformer 10 and voltage information of the power transmission line, a short-circuit directional relay 4 collectively interrupts first-third breakers 2<SB>1</SB>-2<SB>3</SB>installed on the R-phase, S-phase and T-phase of the power transmission line respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a direction protection relay device and a power direction relay device, and in particular, a direction protection relay device for protecting a three-phase AC circuit from a short circuit accident and a power for protecting the three-phase AC circuit from reverse power flow. The present invention relates to a direction relay device.

  Conventionally, in a three-phase AC circuit, in order to protect the three-phase AC circuit from a short-circuit accident, a short-circuit direction relay (DS) is installed for each phase (see Patent Document 1 below).

For example, as shown in FIG. 16, the first short directional relay 4 _1, enter the short-circuit current of the R-phase from the power distribution wires of the first current transformer installed in the R-phase (CT) 3 ₁ enter the phase voltage V _S of the phase voltage V _R and S phases of the R-phase from potential transformer (PT) 6 installed on the bus together, also in the second short directional relay 4 _2, transmission and distribution lines The S-phase short-circuit current is input from the _second current transformer 32 installed in the S-phase, and the S-phase phase voltage V _S and the T-phase phase voltage V _T are input from the instrument transformer 6. in addition, the third short-circuit direction relay 4 _3, from the third current transformer 3 ₃ installed in the T-phase of the transmission and distribution lines from the potential transformer 6 inputs the short-circuit current of the T-phase of the R-phase enter the phase voltage V _T of the phase voltage V _R and T phases, when the short-circuit fault occurs in the transmission and distribution lines, as shown below, the accident appearance Depending on transmission and distribution lines of R-phase, bulk blocked in the first to third circuit breaker 2 ₁ to 2 ₃ of the first to third short directional relay 41 _{to 3} of which are respectively installed on the S-phase and T-phase is doing.
(1) In case of short circuit between R phase and S phase Short circuit current in the internal direction (direction toward the end of the transmission and distribution line) flows in the R phase of the transmission and distribution line, and short circuit in the external direction to the S phase of the transmission and distribution line Current flows. Therefore, the first short-circuit direction relay 4 ₁ operates based on the R-phase short-circuit current and the R-phase to S-phase line voltage V _RS , thereby connecting the _first to _third circuit breakers 2 ₁ to 2 ₃ . Shut off all at once.
(2) In the case of a short-circuit accident between the S phase and the T phase An internal short circuit current flows in the S phase of the transmission and distribution line, and an external short circuit current flows in the T phase of the transmission and distribution line. Accordingly, the second short-circuit direction relay 4 ₂ operates based on the S-phase short-circuit current and the S-phase to T-phase line voltage V _ST , and the _first to _third circuit breakers 2 ₁ to 2 ₃ are connected. Shut off all at once.
(3) In the case of a short circuit accident between the T phase and the R phase An internal short circuit current flows in the T phase of the transmission and distribution line, and an external short circuit current flows in the R phase of the transmission and distribution line. Therefore, the third short-circuit direction relay 4 ₃ operates based on the T-phase short-circuit current and the T-phase to R-phase line voltage V _TR , and the _first to _third circuit breakers 2 ₁ to 2 ₃ are connected. Shut off all at once.
(4) In the case of a short circuit accident between the R phase, the S phase, and the T phase Short circuit currents in the internal direction flow in the R phase, the S phase, and the T phase of the transmission and distribution lines. Accordingly, the first to third short-circuit direction relays 4 ₁ to 4 ₃ are connected to the R-phase, S-phase, and T-phase short-circuit currents, the R-phase to S-phase line voltage V _RS , and the S-phase to T-phase line spacing. The _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively cut off by operating on the basis of the voltage V _ST and the T-phase to R-phase line voltage V _TR .

As for the distance relay (DZ), as shown in FIG. 17, the first distance relay 20 _1, of the first current transformer 3 ₁ and the power distribution wires installed in the R-phase of the transmission and distribution lines the third current transformer 3 ₃ R phase and T-phase of the short circuit current from voltage transformer 6 installed to the bus together with the respectively input R phase and T-phase phase voltage V _R of the installed in the T phase, V _T is input, and the second distance relay 20 ₂ is supplied with the R phase and S from the _first current transformer 3 ₁ and the second current transformer 3 ₂ installed in the S phase of the transmission and distribution line. The short-circuit current of the phase is input and the phase voltages V _R and V _S of the R phase and the S phase are input from the instrument transformer 6, and the second and third phase relays 20 ₃ are connected The S-phase and T-phase short-circuit currents are input from the current transformers 3 ₂ and 3 _3, and the S-phase phase voltage V _S is input from the instrument transformer 6. And enter the phase voltage V _T of the T-phase, when the short-circuit fault occurs in the transmission and distribution lines, as shown below, R-phase of the transmission and distribution lines according to the accident aspect, each S-phase and T-phase The installed _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively disconnected by the _{first to third} distance relays 20 _{1 to} 20 ₃ .
(1) In the case of a short circuit accident between the R phase and the S phase A short circuit current in the internal direction flows in the R phase of the transmission and distribution line, and a short circuit current in the external direction flows in the S phase of the transmission and distribution line. Therefore, the second distance relay 20 _2, operates on the basis of the line voltage V _RS of the differential current and R-phase -S phase of the short circuit current of the short circuit current and the S-phase of the R-phase, the first to third All circuit breakers 2 _{1 to} 2 ₃ are collectively shut off.
(2) In the case of a short-circuit accident between the S phase and the T phase An internal short circuit current flows in the S phase of the transmission and distribution line, and an external short circuit current flows in the T phase of the transmission and distribution line. Accordingly, the third distance relay 20 ₃ operates based on the S-phase short-circuit current, the difference current between the T-phase short-circuit currents, and the S-phase to T-phase line voltage V _ST, and the first to third All circuit breakers 2 _{1 to} 2 ₃ are collectively shut off.
(3) In the case of a short circuit accident between the T phase and the R phase An internal short circuit current flows in the T phase of the transmission and distribution line, and an external short circuit current flows in the R phase of the transmission and distribution line. Therefore, first distance relay 20 ₁ operates on the basis of the line voltage V _TR of the differential current and the T phase -R phase of the short circuit current and short-circuit current of R-phase of T-phase, the first to third All circuit breakers 2 _{1 to} 2 ₃ are collectively shut off.
(4) In the case of a short circuit accident between the R phase, the S phase, and the T phase Short circuit currents in the internal direction flow in the R phase, the S phase, and the T phase of the transmission and distribution lines. Accordingly, the first to third distance relay 20 ₁ to 20 ₃ operate respectively, collectively blocking the first to third circuit breaker 2 ₁ to 2 _3.

For even line selection relay (SS), as shown in FIG. 18, in the first line selection relay 30 _1, the first and second transmission and distribution lines 1L, R-phase of 2L (equilibrium 2-line transmission and distribution lines) Is connected to the first and _fourth current transformers 3 ₁ and 3 ₄ respectively installed in the first and second current transmission and distribution lines 1L and 2L, and the R phase short-circuit current is input thereto, and the instrument transformer is installed on the bus. enter the phase voltage V _R of the R-phase from vessel 6, also in the second line selection relay 30 _2, second and disposed respectively first and second transmission and distribution lines 1L, the S phase of 2L The S-phase short-circuit current of the first and second power transmission lines 1L, 2L is input from the _fifth current transformers 3 ₂ , 3 ₅ and the S-phase phase voltage V _S is input from the instrument transformer 6. , further, the third line selection relay 30 _3, the first and second transmission and distribution lines 1L, respectively set to the T-phase of 2L Have been the third and sixth current transformer 3 _3, 3 to ₆ first and second transmission and distribution lines 1L, the phase voltage T-phase from the potential transformer 6 inputs the short-circuit current of the T-phase of 2L enter the V _T, the first or second transmission and distribution lines 1L, when the short-circuit failure occurs in 2L, as shown below, depending on the accident aspect, short-circuit fault in the first transmission and distribution lines 1L If the _first to _third circuit breakers 2 ₁ to 2 ₃ are determined to be collectively disconnected by the _first to _third line selection relays 30 ₁ to 30 ₃ , and short-circuited to the second transmission / distribution line 2L. If it is determined that an accident has occurred, the fourth to _sixth circuit breakers 2 ₁ to 2 ₆ are collectively disconnected by the _first to _third line selection relays 30 ₁ to 30 ₃ .
(1) In the case of a short circuit accident between the R phase and the S phase For example, when a short circuit accident occurs between the R phase and the S phase of the first transmission and distribution line 1L, the first and second transmission lines 1L and 2L While an internal short-circuit current flows in the R phase, an external short-circuit current flows in the S phase of the first and second transmission and distribution lines 1L and 2L. Thus, the first line selection relay 30 _1, first and second transmission line 1L, operates on the basis of the phase voltage V _R of the differential current and the R-phase of the short-circuit current of the R-phase of 2L, first To the third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.
(2) In the case of a short circuit accident between the S phase and the T phase For example, when a short circuit accident occurs between the S phase and the T phase of the first transmission and distribution line 1L, the first and second transmission lines 1L and 2L A short-circuit current in the internal direction flows in the S phase, and a short-circuit current in the external direction flows in the T phase of the first and second power distribution lines 1L and 2. Accordingly, the second line selection relay 30 ₂ operates based on the difference current between the S-phase short-circuit currents of the first and second transmission lines 1L and 2L and the S-phase phase voltage V _S, and the first To the third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.
(3) In the case of a short circuit accident between the T phase and the R phase For example, when a short circuit accident occurs between the T phase and the R phase of the first transmission and distribution line 1L, the first and second transmission lines 1L and 2 While a short-circuit current in the internal direction flows in the T phase, a short-circuit current in the external direction flows in the R phase of the first and second transmission and distribution lines 1L and 2. Thus, the third line selection relay 30 ₃ operates on the basis of the phase voltage V _R of the first and second transmission and distribution lines 1L, differential current 2 T-phase of the short-circuit current and T-phase, the 1 to the third circuit breakers 2 ₁ to 2 ₃ collectively blocking.
(4) In the case of a short circuit accident between the R phase, the S phase, and the T phase For example, when a short circuit accident occurs between the T phase and the R phase of the first transmission and distribution line 1L, the first and second transmission and distribution lines 1L , 2 short-circuit currents flow in the R phase, S phase, and T phase, respectively. Accordingly, the first to third line selection relays 30 ₁ to 30 ₃ operate to collectively shut off the _first to _third circuit breakers 2 ₁ to 2 ₃ .

Further, in the three-phase AC circuit, a power direction relay (DP) is used in order to protect the three-phase AC circuit from reverse power flow (see, for example, Patent Document 2 below).
For example, as shown in FIG. 19, _first to _third power direction relays 40 ₁ to 40 ₃ are used to protect the transmission and distribution lines from the reverse power flow from the power generation equipment G installed downstream of the bus. The first power direction relay 40 ₁ receives the R-phase current from the _first current transformer 3 ₁ installed in the R phase of the transmission and distribution line, and from the instrument transformer 6 installed in the bus. enter the phase voltage V _T of R-phase of the phase voltage V _R and T phases, also in the second power directional relay 40 _2, the second current transformer installed in the S phase of the transmission and distribution lines 3 ₂ The S-phase current is input, and the R-phase voltage V _R and the S-phase voltage V _S are input from the instrument transformer 6. Further, the third power direction relay 40 ₃ has a power transmission and distribution line. Oyo phase voltage V _S of the S-phase from the potential transformer 6 receives an input of the third current current transformer 3 ₃ T phase installed in T phase Enter the phase voltage V _T of the T-phase, R-phase of the transmission and distribution lines, when detected as follows backward flow generated in the S-phase and T-phase, the transmission and distribution lines R-phase, S-phase and T-phase The _first to _third circuit breakers 2 ₁ to 2 ₃ respectively installed in the first and third power direction relays 40 ₁ to 40 ₃ are collectively cut off.
When a reverse power flow occurs in the transmission / distribution line, as indicated by broken arrows in FIG. 19, the R-phase, S-phase, and T-phase of the transmission / distribution line are opposite to the bus (hereinafter, this direction is referred to as “+ direction”). )), Effective currents i _RP , i _SP , i _TP flow with a phase difference of 120 °.
Accordingly, the first power direction relay 40 ₁ has the R-phase to T-phase line voltage V _RT calculated from the R-phase phase voltage V _R and the T-phase phase voltage V _T inputted from the instrument transformer 6. Is used as a reference voltage and operates based on the R-phase effective current i _RP input from the _first current transformer 31 and the reference voltage (line voltage V _RT ), and the R-phase effective current i _{When the RP} enters the operating range shown in FIG. 20, the _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively disconnected.
Second power directional relay 40 _2, based on the line voltage V _SR of S phase -R phase calculated from the phase voltage V _S of the voltage transformer 6 a phase voltage of the R-phase input from V _R and S phases used as a voltage, and operates based on the active current i _SP and the reference voltage of S-phase inputted from the second current transformer 3 ₂ (line voltage V _SR), the effective current i _SP of S-phase When entering the operating range (see FIG. 20), the _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.
Third power directional relay 40 _3, based on the line voltage V _TS T-phase -S phase calculated from the phase voltage V _T of S-phase of the phase voltage V _S and T phases input from the potential transformer 6 used as a voltage, and operates based on the active current i _TP and the reference voltage of the T-phase input from the third current transformer 3 ₃ (line voltage V _TS), T-phase current i _TP operation When entering the range (see FIG. 20), the _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.

In the _first to _third power direction relays 40 ₁ to 40 ₃ shown in FIG. 19, the line voltage is used as a reference voltage for detecting reverse power flow generated in the R phase, S phase, and T phase of the transmission and distribution lines. Although the voltages V _RT , V _SR , and V _TS are used, there is a power direction relay that uses a single-phase voltage.
The maximum sensitivity angle when the line voltages V _RT , V _SR , and V _TS are used as the reference voltage is 30 °, and the maximum sensitivity angle when the single-phase voltage is used as the reference voltage is 0 °.
Furthermore, instead of using three power direction relays, only one power direction relay is used to detect reverse power flow for only one of the R phase, S phase, and T phase of the transmission and distribution line. Yes.
JP 2001-16767 A JP 54-67658 A

  However, because there are three sets of current transformers and direction protection relays (short-circuit direction relays, distance relays and line selection relays) and power direction relays for transmission and distribution lines, current transformers, direction protection relays and power direction relays There is a demand to reduce the equipment cost by reducing the number of installations.

  An object of the present invention is to provide a direction protection relay device and a power direction relay that can reduce the number of current transformers, direction protection relays, and power direction relays for protecting a three-phase AC circuit from a short circuit accident or reverse power flow. It is to provide an electric device.

The direction protection relay device of the present invention is a direction protection relay device for protecting a three-phase AC circuit from a short-circuit accident, and an arbitrary two of the three-phase AC circuit is mounted on an annular core wound with a secondary coil. When detecting a short-circuit accident based on a two-phase through current transformer having a different number of passes through the phase in the same direction, a short-circuit current input from the two-phase through current transformer, and voltage information of the three-phase AC circuit And a direction protection relay that collectively shuts off circuit breakers installed in each phase of the three-phase AC circuit.
Here, the direction protection relay further includes an accident mode determination means for determining an accident mode of the short-circuit fault of the three-phase AC circuit, and the fault mode is added to the short-circuit current input from the two-phase through current transformer. A corrected short-circuit current is calculated by multiplying a predetermined multiple according to the determination result of the accident aspect in the determination means, and when a short-circuit accident is detected based on the calculated corrected short-circuit current and the voltage information of the three-phase AC circuit, the three Circuit breakers installed in each phase of the phase AC circuit may be collectively shut off.
The accident mode determination means determines whether the three-phase AC circuit has three line voltages (V _RS , V _ST , V _TR ), three phase voltages (V _R , V _S , V _T ) or a phase / line voltage. Based on this, the accident aspect of the short circuit accident of the three-phase AC circuit may be determined.
The accident mode determination means is based on the voltage value and phase of one line voltage (V _RS , V _ST , V _TR ) and one phase voltage (V _R , V _S , V _T ) of the three-phase AC circuit. Thus, the accident aspect of the short circuit accident of the three-phase AC circuit may be determined.
The accident mode judging means is configured to _detect a voltage value and a phase of one line voltage (V _RS , V _ST , V _TR ) of the three-phase AC circuit and a short-circuit current (I _Ry) input from the two-phase through current transformer. ) Phase of the three-phase AC circuit may be determined on the basis of the phase).
The first phase voltage (V _R ) of the three-phase AC circuit is in the polarity direction, and the second phase voltage (V _S ) of the three-phase AC circuit is in the opposite polarity direction. The first to second phases are used for determining the accident aspect of the short-circuit fault of the three-phase AC circuit, where the secondary side is connected so as to synthesize the phase voltage (V _T ) by doubling in the opposite polarity direction. An accident mode judging transformer (110) for obtaining a composite voltage (V _RS-2T ) of the phase voltages of the three phases, wherein the accident mode judging means is inputted from the accident mode judging transformer. The accident aspect of the short-circuit accident of the three-phase AC circuit may be determined based on the voltage value and phase of the combined voltage and the phase of the short-circuit current (I _Ry ) input from the two-phase through current transformer. .
The first phase voltage (V _R ) of the three-phase AC circuit is in the polarity direction, and the second phase voltage (V _S ) of the three-phase AC circuit is in the opposite polarity direction. The first to third are used to determine the accident aspect of the short-circuit accident of the three-phase AC circuit in which the secondary side is connected so that the phase voltage (V _T ) is doubled and synthesized in the polarity direction. And an accident mode determination transformer (120) for obtaining a composite voltage (V _{R-S + 2T} ) of the phases of the phases, and the accident mode determination means is input from the accident mode determination transformer Even if the accident aspect of the short circuit accident of the three-phase AC circuit is determined based on the voltage value and phase of the synthesized voltage and the phase of the short circuit current (I _Ry ) input from the two-phase through current transformer Good.
The first phase voltage (V _R ) of the three-phase AC circuit is multiplied by a in the polarity direction or the antipolar direction, and the second phase voltage (V _S ) of the three-phase AC circuit is changed in the polarity direction or antipolar direction. And the secondary side is connected so that the third phase voltage (V _T ) of the three-phase AC circuit is multiplied by c in the polarity direction or the opposite polarity direction to be combined, and the three-phase AC A _fault condition judging transformer for obtaining a composite voltage (V _{aR + bS + cT} ) of the phase voltages of the first to third phases used for judging the accident situation of the short circuit accident of the circuit; The accident aspect determination means is based on the voltage value and phase of the combined voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the two-phase through current transformer. You may determine the accident aspect of the short circuit accident of the said three-phase alternating current circuit.
The two-phase through current transformer (10) is installed in a transmission / distribution line, and the first phase and the second phase of the transmission / distribution line are different in the same direction on the annular core of the two-phase through current transformer. If the directional protection relay detects a short-circuit fault based on the short-circuit current (I _Ry ) input from the two-phase through current transformer and the voltage information of the transmission / distribution line, The short circuit direction relay (4) which interrupts | blocks the _1st thru | or 3rd circuit breaker (2 1-2 ₃ ) installed in each phase of a distribution line collectively may be sufficient.
The two-phase through current transformer (10) is installed in a transmission / distribution line, and the first phase and the second phase of the transmission / distribution line are different in the same direction on the annular core of the two-phase through current transformer. If the directional protection relay detects a short-circuit fault based on the short-circuit current (I _Ry ) input from the two-phase through current transformer and the voltage information of the transmission / distribution line, The distance relay (20) which interrupts | blocks the _1st thru | or 3rd circuit breaker (2 1-2 ₃ ) installed in each phase of a distribution line collectively may be sufficient.
The distance relay is based on a correction voltage (V _Ry ) obtained from the combined voltage input from the above-described fault condition determination transformer and a short-circuit current (I _Ry ) input from the two-phase through current transformer. Thus, a short circuit accident in the three-phase AC circuit may be detected.
The two-phase through current transformers are first and second two-phase through current transformers (10 ₁ , 10 ₂ ) installed in the first and second transmission and distribution lines (1L, 2L), respectively. A first phase and a second phase of the first transmission / distribution line are passed through the annular core of the first two-phase through current transformer a different number of times in the same direction, and the second two-phase penetration The first phase and the second phase of the second transmission / distribution line are passed through the annular iron core of the current transformer a different number of times in the same direction, and the direction protection relay is connected to the first two-phase Based on the short-circuit current (I _Ry ), which is the difference between the short-circuit current input from the feed-through current transformer and the short-circuit current input from the second two-phase feed-through current transformer, and the voltage information of the transmission and distribution lines When it is detected that a short circuit accident has occurred in the first transmission / distribution line, the first to the first installed in each phase of the first transmission / distribution line When the third circuit breaker (2 ₁ to 2 ₃ ) is cut off at once and it is detected that a short circuit accident has occurred in the second transmission / distribution line based on the short circuit current and the voltage information of the transmission / distribution line, It may be a line selection relay (30) that collectively shuts off the _fourth to _sixth circuit breakers (2 ₄ to 2 ₆ ) installed in each phase of the second power transmission and distribution line.
The power direction relay device of the present invention is a power direction relay device for protecting a three-phase AC circuit from reverse power flow, and an arbitrary 2 of the three-phase AC circuit is mounted on an annular core wound with a secondary coil. A two-phase through current transformer (10) having a phase penetrated in the same direction by different times, a current (i _Ry ) inputted from the two-phase through current transformer, and an instrument transformer (6) When a reverse power flow is detected based on the reference voltage obtained from the voltage information of the three-phase AC circuit, _first to _third circuit breakers (2 ₁ to 2 ₃ ) installed in the respective phases of the three-phase AC circuit And a power direction relay (40) that collectively cuts off the power.
The power direction relay calculates a correction current (i _Ry ') by multiplying the current input from the two-phase through current transformer by a predetermined multiple, and reverses based on the calculated correction current and the reference voltage. When the power flow is detected, the first to third circuit breakers may be collectively disconnected.
The power direction relay uses a voltage obtained by advancing the phase of the reference voltage by 90 ° as another reference voltage, or a current input from the two-phase through current transformer or a correction current calculated by multiplying the current by a predetermined multiple And the other reference voltage may be detected to function as a reactive power direction relay.

The direction protection relay device and the power direction relay device of the present invention have the following effects.
(1) By using a two-phase through current transformer, the number of installed current transformers, direction protection relays and power direction relays to protect the three-phase AC circuit from short-circuit accidents and reverse power flow can be reduced. Cost can be reduced.
(2) Although the amplitude of the short-circuit current output from the two-phase through current transformer differs depending on the accident aspect of the short-circuit accident, the detection sensitivity and operating time of the direction protection relay are corrected by correcting the short-circuit current amplitude according to the accident aspect. Can be the same.
(3) The first phase voltage is multiplied by a in the polar or antipolar direction, the second phase voltage is multiplied by b in the polar or antipolar direction, and the third phase voltage is polar or antipolar. By using an accident mode determination transformer whose secondary side is connected so as to be multiplied by c in the direction, the voltage value and phase of the composite voltage output from the accident mode determination transformer and the phase of the short circuit current The accident aspect of the short-circuit accident can be determined based on the above.
(4) By using another reference voltage obtained by advancing the phase of the reference voltage by 90 °, the power direction relay can function as a reactive power direction relay.

  The above-mentioned purpose is achieved by using a two-phase through current transformer in which any two phases of a three-phase AC circuit are penetrated in the same direction by different numbers of times through an annular core wound with a secondary coil. When a short-circuit fault is detected based on the short-circuit current input from the phase-through current transformer and the line voltage of the three-phase AC circuit, the circuit breakers installed in each phase of the three-phase AC circuit are collectively shut off. When the power direction relay detects the reverse power flow based on the current input from the two-phase through current transformer and the reference voltage obtained from the voltage information of the three-phase AC circuit input from the instrument transformer, the three-phase AC This was realized by shutting off the circuit breakers installed in each phase of the circuit.

Hereinafter, embodiments of the direction protection relay device and the power direction relay device of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the direction protection relay device according to the first embodiment of the present invention includes a two-phase through current transformer 10 installed on a transmission / distribution line, and an instrument transformer 6 installed on a bus. The R phase obtained from the short-circuit current I _Ry input from the two-phase through current transformer 10 and the R, S and T phase voltages V _R , V _S and V _T input from the instrument transformer 6. -When a short circuit accident is detected on the transmission / distribution line based on the S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST and the T-phase / R-phase line voltage V _TR R phase, and a short-circuit direction relay 4 for collectively blocking the first to third circuit breaker 2 ₁ to 2 ₃ of which are respectively installed on the S-phase and T-phase.

Here, the two-phase through current transformer 10 is a through-type current transformer in which the R phase and the S phase of the power transmission and distribution line are penetrated in the same direction through an annular core around which a secondary coil is wound. That is, both the R phase and the S phase of the power transmission and distribution line are penetrated in the polarity direction of the two-phase through current transformer 10 (direction from the first opening surface of the annular core to the second opening surface of the annular core). .
In addition, the R phase of the transmission / distribution line passes through the two-phase through current transformer 10 only once, but the S phase of the transmission / distribution line passes through the two-phase through current transformer 10 twice. As a result, the two-phase through current transformer 10 outputs a sum current of a current flowing through the R phase of the power transmission and distribution line and a current obtained by doubling the current flowing through the S phase.

Therefore, when the load currents flowing in the R phase, S phase, and T phase of the transmission / distribution line when no short circuit accident has occurred are represented by I _R , I _S , I _T , as shown in FIG. Since the phase load current I _R and the S phase load current I _S flow through the annular core of the two-phase through current transformer 10 in the polarity direction with a phase difference of 120 °, the two-phase through current transformer 10 The load current I input to the short-circuit direction relay 4 is a vector sum of the R-phase load current I _R and the current obtained by doubling the S-phase load current I _S (= 2I _S ), and the amplitude of the load current I is R It becomes 3 ^1/2 times the amplitude of the phase load current I _R (the S phase load current I _S ).
I = I _R + 2I _S
| I | = | I _R + 2I _S | = 3 ^1/2 × | I _R | (= 3 ^1/2 × | I _S |)
Therefore, in order to make the short-circuit direction relay 4 the same as the amplitude of the load current input to the conventional _first to _third short-circuit direction relays 4 ₁ to 4 ₃ shown in FIG. The corrected load current I ′ is calculated by multiplying the load current I by 1/3 ^1/2 .
I ′ = I × 1/3 ^1/2
| I ′ | = | I | × 1/3 1/ ^2- = | I _R | (= | I _S |)

In addition, when a short circuit accident occurs in the transmission / distribution line, the short-circuit currents flowing in the R phase, S phase, and T phase of the transmission / distribution line are represented by I _FR , I _FS , I _FT (impedance angle is θ). The short-circuit direction relay 4 operates as follows according to the accident aspect.
(1) In the case of a short circuit accident between the R phase and the S phase When a short circuit accident between the R phase and the S phase occurs, the short circuit current I _FR of the R phase is generated in the R phase of the power transmission and distribution line as shown by the broken arrow in FIG. The S-phase short-circuit current I _FS flows in the S-phase of the transmission / distribution line, and the S-phase short-circuit current I _FS flows in the external direction. However, the T-phase short-circuit current I _FT does not flow in the T-phase of the transmission / distribution line.
Therefore, the short-circuit current I _Ry output from the two-phase through current transformer 10 to the short-circuit direction relay 4 is obtained by doubling the R-phase short-circuit current I _FR and the S-phase short-circuit current I _FS (= 2I _FS ). Although it is a vector sum, since the phase difference between the R-phase short-circuit current I _FR and the S-phase short-circuit current I _FS is 180 °, the amplitude of the short-circuit current I _Ry is S-phase as shown in FIG. _Is the amplitude of the short-circuit current I _FS (R-phase short-circuit current I _FR ).
I _Ry = I _FR + 2I _FS
| I _Ry | = | I _FR + 2I _FS | = | I _FS | (= | I _FR |)
In FIG. 3, the short-circuit currents I _FR , I _FS , I _FT flowing in the internal direction of the transmission / distribution line are solid arrows, and the short-circuit currents I _FR , I _FS , I _FT flowing in the external direction of the transmission / distribution line are This is indicated by a dashed line arrow.
Therefore, in order to make the short-circuit direction relay 4 the same as the amplitude of the short-circuit current input to the conventional _first to _third short-circuit direction relays 4 ₁ to 4 ₃ shown in FIG. The corrected short-circuit current I _Ry 'is calculated by multiplying the short-circuit current I _Ry by 1.
I _Ry '= I _Ry × 1
| I _Ry '| = | I _Ry | × 1 = | I _FS | (= | I _FR |)
The short-circuit direction relay 4 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR. Based on the above, the magnitude and direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the R phase and the S phase of the transmission and distribution line, as shown in FIG. 3A, the calculated corrected short circuit current I _Ry ′ and the line voltage V _RS between the R phase and the S phase ( The magnitude and direction of the short-circuit current I _Ry is determined based on the negative polarity.
When it is determined that a short-circuit accident has occurred in the transmission / distribution line, the short-circuit direction relay 4 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ .
(2) In the case of a short-circuit accident between the S phase and the T phase When a short circuit accident occurs between the S phase and the T phase, as shown by the dashed arrows in FIG. 4, the S phase short circuit current I _FS There flow inside direction, but the short-circuit current I _FT T-phase to the T phase of the power distribution wires flows outward, the R-phase transmission and distribution lines does not flow a short-circuit current I _FR of R-phase.
Therefore, the short-circuit current I _Ry output from the two-phase through current transformer 10 to the short-circuit direction relay 4 is a current (= 2I _FS ) that is twice the S-phase short-circuit current I _FS, and the amplitude of the short-circuit current I _Ry is As shown in FIG. _3B , the amplitude of the S-phase short-circuit current I _FS is twice.
I _Ry = 2I _FS
| I _Ry | = 2 × | I _FS |
Therefore, in order to make the short-circuit direction relay 4 the same as the amplitude of the short-circuit current input to the conventional _first to _third short-circuit direction relays 4 ₁ to 4 ₃ shown in FIG. The short-circuit current I _Ry is halved to calculate a corrected short-circuit current I _Ry '.
I _Ry '= I _Ry × 1/2
| I _Ry '| = | I _Ry | × 1/2 = | I _FS |
The short-circuit direction relay 4 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR. Based on the above, the magnitude and direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident S phase -T phase of transmission and distribution lines, as shown in FIG. 3 (b), calculated as the correction circuit current I _Ry 'and the line voltage V _ST of S phase -T phase Is used to determine the magnitude and direction of the short-circuit current I _Ry .
When it is determined that a short-circuit accident has occurred in the transmission / distribution line, the short-circuit direction relay 4 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ .
(3) When T phase -R phase short fault when T-phase -R phase short-circuit accident occurs, as indicated by broken line arrow in FIG. 5, the short-circuit current of the T-phase to the T phase of the transmission and distribution lines I _FT There flow inside direction, but the short-circuit current I _FR of R-phase to R-phase of transmission and distribution lines to flow to the outside direction, the S-phase of the transmission and distribution lines does not flow a short-circuit current I _FS of S phase.
Thus, two-phase through current transformer short-circuit current I _Ry from 10 is output to the short directional relay 4 short-circuit current I _FR next to R-phase, the amplitude of the short-circuit current I _Ry is R-phase as shown in FIG. 3 (c) The amplitude of the short-circuit current _{IFR is} as follows.
I _Ry = I _FR
| I _Ry | = | I _FR |
Therefore, in order to make the short-circuit direction relay 4 the same as the amplitude of the short-circuit current input to the conventional _first to _third short-circuit direction relays 4 ₁ to 4 ₃ shown in FIG. The corrected short-circuit current I _Ry 'is calculated by multiplying the short-circuit current I _Ry by 1.
I _Ry '= I _Ry × 1
| I _Ry '| = | I _Ry | × 1 = | I _FR |
The short-circuit direction relay 4 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR. Based on the above, the magnitude and direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the T phase and the R phase of the transmission and distribution line, as shown in FIG. 4A, the calculated corrected short circuit current I _Ry ′ and the line voltage V _TR (T phase to R phase) The magnitude and direction of the short-circuit current I _Ry is determined based on the negative polarity.
When it is determined that a short-circuit accident has occurred in the transmission / distribution line, the short-circuit direction relay 4 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ .
(4) In the case of a short-circuit accident between R phase, S phase, and T phase When a short circuit accident between R phase, S phase, and T phase occurs, as shown by the dashed arrows in FIG. The R-phase short-circuit current I _FR , the S-phase short-circuit current I _FS, and the T-phase short-circuit current I _FT flow in the internal direction with a phase difference of 120 degrees.
Therefore, the short-circuit current I _Ry output from the two-phase through current transformer 10 to the short-circuit direction relay 4 is obtained by doubling the R-phase short-circuit current I _FR and the S-phase short-circuit current I _FS (= 2I _FS ). Although it is a vector sum, since the phase difference between the R-phase short-circuit current I _FR and the S-phase short-circuit current I _FS is 120 °, the amplitude of the short-circuit current I _F1 is R-phase as shown in FIG. This is 3 ^1/2 times the amplitude of the short-circuit current I _FR (S-phase short-circuit current I _FS ).
I _Ry = I _FR + 2I _FS
| I _Ry | = | I _FR + 2I _FS | = 3 ^1/2 × | I _FR | (= 3 ^1/2 × | I _FS |)
Therefore, in order to make the short-circuit direction relay 4 the same as the amplitude of the short-circuit current input to the conventional _first to _third short-circuit direction relays 4 ₁ to 4 ₃ shown in FIG. The short-circuit current I _Ry is multiplied by 1/3 ^1/2 to calculate a corrected short-circuit current I _Ry '.
I _Ry '= I _Ry × 1/3 ^1/2
_{| I Ry '| = | I} Ry | × 1/3 1/2 - = | I FR | (= | I FS |)
Further, since the short circuit current I _Ry is input from the two-phase through current transformer 10 to the short circuit direction relay 4 with a delayed phase of 30 °, the short circuit direction relay 4 also performs phase correction of the corrected short circuit current I _Ry '.
The short-circuit direction relay 4 includes a phase-corrected corrected short-circuit current I _Ry ′, an R-phase / S-phase line voltage V _RS , an S-phase / T-phase line voltage V _ST, and a T-phase / R-phase line voltage V Based on _TR , the magnitude and direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the R phase, the S phase, and the T phase of the transmission and distribution line, as shown in FIG. 4B, the corrected short circuit current I _Ry 'corrected for the phase and the line between the T phase and the R phase line. The magnitude and direction of the short-circuit current I _Ry is determined based on the voltage V _TR .
When it is determined that a short-circuit accident has occurred in the transmission / distribution line, the short-circuit direction relay 4 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ .

  The two-phase through-current transformer 10 penetrates the R phase of the transmission / distribution line once and the S phase twice, but penetrates the S phase of the transmission / distribution line once and the T phase twice. It may be penetrated, or the T phase of the transmission / distribution line may be penetrated once and the R phase may be penetrated twice.

However, depending on the accident aspect, the short-circuit direction relay 4 has the magnification shown in Table 1 depending on the combination of the phases of the transmission and distribution lines (hereinafter referred to as “CT connection”) that penetrate the two-phase through current transformer 10. The corrected short-circuit current I _Ry ′ is calculated, and it is determined whether or not a short-circuit accident has occurred in the transmission and distribution line based on the calculated corrected short-circuit current I _Ry ′ and the line voltage shown in Table 2.
In Tables 1 and 2, “+” in the CT connection indicates that the corresponding phase is penetrated in the polarity direction of the two-phase through current transformer.

As described above, in the direction protection relay device according to the present embodiment, the number of installed current transformers and short-circuit direction relays can be further reduced by using the two-phase through current transformer 10, but the load current As the amplitude of I becomes 3 ^1/2 times, the amplitude of the short-circuit current I _Ry in the short-circuit accident between the S phase and the T phase becomes short-circuit current I in the short-circuit accident between the R phase and the S phase and the short circuit accident between the T phase and the R phase. The amplitude of _Ry is twice the amplitude of _{Ry, and} the amplitude of short-circuit current _IRy in a short-circuit accident between R-phase, S-phase and T-phase is short-circuit current in short-circuit accident between R-phase and S-phase and short-circuit accident between T-phase and R-phase. Since it becomes 3 ^1/2 times the amplitude of I _Ry , the short-circuit current I _Ry is corrected according to the accident aspect in order to make the detection sensitivity and operation time of the short-circuit direction relay the same for all accident aspects. There is a need.

Therefore, the short-circuit direction relay 4 determines the accident aspect using any one of the following first to fifth accident aspect determination methods, and determines the accident aspect to the short-circuit current I _Ry from the two-phase through current transformer 10. The short-circuit current I _Ry is corrected by multiplying a predetermined multiple (see Table 1) according to the result.

(First accident mode judgment method)
The accident aspect is determined based on the three line voltages, the three phase voltages, or the phase / line voltage (combination of the phase voltage and the line voltage).

Table 3 shows the accident condition determination conditions based on the three line voltages. In addition, ○ mark indicates the line voltage in which the voltage drop is detected based on the voltage information from the undervoltage relay installed on the bus, and the X mark is based on the voltage information from this undervoltage relay. Indicates a line voltage in which no voltage drop was detected (voltage drop detection sensitivity is about 75 to 80% of the rated voltage).

Table 4 shows the accident condition determination conditions based on the three phase voltages. In addition, a circle indicates a phase voltage in which a voltage drop is detected based on voltage information from an undervoltage relay installed on the bus, and a cross indicates a voltage based on voltage information from the undervoltage relay. The phase voltage in which no decrease was detected is indicated (the voltage drop detection sensitivity is about 75 to 80% of the rated voltage).

Table 5 shows the accident condition determination conditions based on the phase / line voltage. The circles indicate the phase voltage and the line voltage at which a voltage drop is detected based on the voltage information from the undervoltage relay installed on the bus, and the x indicates the voltage information from this undervoltage relay. The phase voltage and the line voltage in which no voltage drop was detected based on the above are shown (the voltage drop detection sensitivity is about 75 to 80% of the rated voltage).

(Second accident mode judgment method)
The accident aspect is determined based on the voltage value and phase of one line voltage and one phase voltage.

For example, based on the fact that the phase of the line voltage V _TR between the T phase and the R phase is 210 ° and the phase of the phase voltage V _R of the _R phase is 0 ° (see FIG. 2B), the transmission and distribution lines The R-phase-S phase line voltage V _RS at the time of the short-circuit accident between the R-phase and S-phase and the S-phase-T-phase line voltage V _ST at the time of the short-circuit accident between the S-phase and the T-phase When 85 V, as well as determined that the short-circuit failure on a condition that the line voltage V _TR of the T-phase -R phase is equal to or less than a predetermined first voltage value k1 = 85 V is generated, a line of T-phase -R phase The voltage V _TR is equal to or lower than a predetermined second voltage value k2 = 104.3 V, and the phase of the line voltage V _TR between the T phase and the R phase before the short circuit accident is 210 ° as a reference. the T-phase -R phase of the phase of the line voltage V _TR is advanced or delayed by a predetermined angular range α (5.95 ° ≦ α ≦ 30 ° or -30 ° α ≦ -5.95 °) determining a short-circuit failure condition has occurred (the following (1-1) and (1-2) refer to formula).
V _TR ≦ [{(110/3 ^1/2 ) × 1.5} ² + (85/2) ² ] ^1/2
≦ (95.26 ² +42.5 ² ) ^1/2
≦ 104.3 (V) (1-1)
α ≧ 30 ° -tan ⁻¹ (42.5 / 95.26)
≧ 5.95 (°) (1-2)

Moreover, the accident aspect is determined as follows.
(1) In the case of a short-circuit accident between the R phase and the S phase The line voltage V _TR between the T phase and the R phase is 104.3 V or less, and the line voltage V _TR between the T phase and the R phase before the short circuit accident is When the phase of the line voltage V _TR between the T phase and the R phase is delayed by the angle range α (+ α) with reference to the phase = 210 °, it is determined that the short-circuit accident occurs between the R phase and the S phase (FIG. 7 ( a)).
(2) In the case of a short circuit accident between the S phase and the T phase The line voltage V _TR between the T phase and the R phase is 104.3 V or less, and the line voltage V _TR between the T phase and the R phase before the short circuit accident is When the phase of the line voltage V _TR between the T phase and the R phase is advanced only within the angle range α (−α) with reference to the phase = 210 °, it is determined that there is a short circuit accident between the S phase and the T phase (FIG. 7). (See (b)).
(3) In the case of a short circuit accident between the T phase and the R phase The line voltage V _TR between the T phase and the R phase is 85 V or less, and the phase of the line voltage V _TR between the T phase and the R phase before the short circuit accident = the line phase of the voltage V _TR of the T-phase -R phase 210 ° as a reference is not or is progressing or has been delayed only within an angular range alpha (i.e., 5.95 ° greater than -5.95 ° And the phase of the R-phase phase voltage V _R before the short circuit accident is 0 ° as a reference, and the phase of the R-phase phase voltage V _R has a predetermined other angle range β (6.76 ° ≦ β ≦ 60 °, see (Equation 1-3)) (−β), it is determined that there is a short circuit accident between the T phase and the R phase (see FIG. 7C).
β ≧ 60 ° -tan ⁻¹ [42.5 / {110 / (2 × 3 ^1/2 )}]
≧ 6.76 (°) (1-3)
(4) In the case of a short circuit accident between R phase, S phase and T phase The line voltage V _TR between T phase and R phase is 85V or less, and the line voltage V _TR between T phase and R phase before the short circuit accident. The phase of the line voltage V _TR between the T-phase and the R-phase is not delayed or advanced by the angle range α with respect to the phase of 210 = 210 ° (that is, greater than −5.95 ° and 5 .. is smaller than .95 °), and the phase of the R phase voltage V _R before the short-circuit accident is 0 ° or the phase of the R phase voltage V _R is delayed or advanced by another angle range β. It is determined that a short-circuit accident between the R-phase, the S-phase, and the T-phase is performed on the condition that it is not (ie, larger than −6.76 ° and smaller than 6.76 °) (FIG. 7D). reference).

Although the T-phase-R-phase line voltage V _TR and the R-phase phase voltage V _R are used, any one of the voltage combinations indicated by circles in Table 6 may be used. However, the short-circuit accident occurrence determination condition and the accident aspect determination condition described above need to be changed according to the combination of voltages.

(Third accident mode determination method)
The accident aspect is determined based on the voltage value and phase of one line voltage and the phase of the short-circuit current _IRy input from the two-phase through current transformer.

For example, based on that phase of the line voltage V _TR of the T-phase -R phase is 210 °, R phase -S phase of the line voltage V _RS during short-circuit accident R phase -S phase of transmission and distribution lines and S phase -T When the line voltage V _ST between phases S phase -T phase when a short circuit accident and 85V of short-circuit failure detection sensitivity, a first voltage line voltage V _TR of the T-phase -R phase is given It is determined that a short-circuit accident has occurred on condition that the value k1 = 85 V or less, and the T-phase to R-phase line voltage V _TR is a predetermined second voltage value k2 = 104.3 V or less, and The phase of the line voltage V _TR between the T phase and the R phase before the short circuit accident = 210 ° as a reference, the phase of the line voltage V _TR between the T phase and the R phase at the time of the short circuit accident is delayed by a predetermined angle range α. A short-circuit accident occurs on the condition that it is moving or advanced (5.95 ° ≦ α ≦ 30 ° or −30 ° ≦ α ≦ −5.95 °) A constant ((1-1) see formula and (1-2) below).

Moreover, the accident aspect is determined as follows.
(1) In the case of a short-circuit accident between the R phase and the S phase The line voltage V _TR between the T phase and the R phase is 104.3 V or less, and the line voltage V _TR between the T phase and the R phase before the short circuit accident is When the phase of the line voltage V _TR between the T phase and the R phase is delayed by the angle range α (+ α) with reference to the phase = 210 °, it is determined that the short-circuit accident occurs between the R phase and the S phase (FIG. 8 ( a)).
(2) In the case of a short circuit accident between the S phase and the T phase The line voltage V _TR between the T phase and the R phase is 104.3 V or less, and the line voltage V _TR between the T phase and the R phase before the short circuit accident is When the phase of the line voltage V _TR between the T phase and the R phase is advanced only within the angle range α (−α) with respect to the phase = 210 ° as a reference, it is determined that there is a short circuit accident between the S phase and the T phase (FIG. 8). (See (b)).
(3) In the case of a short circuit accident between the T phase and the R phase The line voltage V _TR between the T phase and the R phase is 85 V or less, and the phase of the line voltage V _TR between the T phase and the R phase before the short circuit accident = The phase of the line voltage V _TR between the T phase and the R phase is not delayed or advanced by an angle range α with respect to 210 ° (that is, greater than −5.95 ° and 5.95 °). And the phase of the short-circuit current I _Ry is determined in consideration of arc resistance and the like with a predetermined first angle range γ (−150 ° ≦ γ ≦ −90 °, γ is an impedance angle θ = 75 °) If it is within the range, it is determined that there is a short circuit accident between the T phase and the R phase (see FIG. 8C).
(4) In the case of a short circuit accident between R phase, S phase and T phase The line voltage V _TR between T phase and R phase is 85V or less, and the line voltage V _TR between T phase and R phase before the short circuit accident. The phase of the line voltage V _TR between the T-phase and the R-phase is not delayed or advanced by the angle range α with respect to the phase of 210 = 210 ° (that is, greater than −5.95 ° and 5 Smaller than .95 °) and the phase of the short-circuit current I _Ry is within a predetermined second angle range δ (−90 ° ≦ δ ≦ −30 °, where δ is an impedance angle θ = 75 ° and arc resistance is taken into consideration. If it is within the range, it is determined that there is a short circuit accident between the R phase, the S phase, and the T phase (see FIG. 8D).

(Fourth accident mode determination method)
An accident mode determination transformer 110 shown in FIG. 9 is installed on the bus, and based on the voltage value and phase of the composite voltage V _RS-2T output from the accident mode determination transformer 110 and the phase of the short-circuit current I _Ry. The accident aspect is judged as follows.
Here, the secondary side of the accident phase determination transformer 110 reverses the phase voltage V _R of the R phase in the polarity direction, the phase voltage V _S of the S phase in the antipolar direction, and the phase voltage V _T of the T phase. They are wired so that they are doubled in the polarity direction for synthesis. As a result, the composite voltage V _RS-2T output from the accident aspect determination transformer 110 is expressed by the following equation.
V _RS-2T = V _R -V _S -2V _T
Further, although the impedance angle θ is usually 75 °, the phase angle of the short-circuit current I _Ry is 90 ° (+ 15 °) which is the maximum angle at the time of a short-circuit accident from 30 ° (−45 °) in consideration of arc resistance. ).

(1) In the case of a short-circuit accident between the R phase and the S phase The voltage value of the composite voltage V _RS-2T is a predetermined first composite voltage value K ₁ = 100.1 V or less (see equation (2-1)). In addition, the phase of the composite voltage V _RS-2T at the time of the short-circuit accident is set to a predetermined first composite voltage angle range ε ₁ (7 based on the fact that the phase of the composite voltage V _RS-2T at the normal time is 19.1 °. .10 ° (= X ₁ ) ≦ ε ₁ ≦ 40.9 ° (= X ₂ ) (Refer to equations (2-2) and (2-3)) (+ ε ₁ ) and short circuit When the phase of the current I _Ry is delayed (+ λ ₁ ) by a predetermined first short-circuit current angle range λ ₁ (160.9 ° ≦ λ ₁ ≦ 220.9 °) (+ λ ₁ ), a short circuit between the R phase and the S phase Judge as an accident.
K ₁ = [(83.15) ² + (72.01 × 85/110) ² ] ^1/2
= 100.1 (V) (2-1)
^{_{X 1 = cos -1 (83.15 /}} 110.0) -cos -1 (83.15 / 100.05)
= 7.10 (°) (2-2)
X ₂ = 60-19.1
= 40.9 (°) (2-3)
(2) In the case of a short circuit accident between the S phase and the T phase The voltage value of the composite voltage V _RS-2T is a predetermined second composite voltage value K ₂ = 107.6 V or less (see the formula (2-4)), In addition, the phase of the composite voltage V _RS-2T at the time of the short-circuit accident is determined to be a predetermined second composite voltage angle range ε ₂ (4 based on the phase of the composite voltage V _RS-2T at the normal time being 19.1 °. .12 ° (= X ₃ ) ≦ ε ₂ ≦ 19.1 ° (= X ₄ ) (see formulas (2-5) and (2-6)) (−ε ₂ ) When the phase of the short-circuit current I _Ry is delayed (+ λ ₂ ) by a predetermined second short-circuit current angle range λ ₂ (100.9 ° ≦ λ ₂ ≦ 160.9 °) (between S phase and T phase) Judged as a short circuit accident.
K ₂ = [(103.94) ² + (36.01 × 85/110) ² ] ^1/2
= 107.6 (V) (2-4)
X ₃ = cos ⁻¹ (103.94 / 110) −cos ⁻¹ (103.94 / 107.60)
= 4.12 (°) (2-5)
X ₄ = 19.1-0
= 19.1 (°) (2-6)
(3) In the case of a short-circuit accident between the T phase and the R phase The voltage value of the composite voltage V _RS-2T is equal to or less than a predetermined third composite voltage value K ₃ = 86.0 V (see formula (2-7)) Further, the phase of the composite voltage V _RS-2T at the time of a short-circuit accident is determined to be a predetermined third composite voltage angle range ε ₃ (3 based on the phase of the composite voltage V _RS-2T at the normal time being 19.1 °. .09 ° (= X ₅ ) ≦ ε ₃ ≦ 79.1 ° (= X ₆ ) (see formulas (2-8) and (2-9)) (−ε ₃ ) When the phase of the short-circuit current I _Ry is delayed by (+ λ ₃ ) within a predetermined third short-circuit current angle range λ ₃ (40.9 ° ≦ λ ₃ ≦ 100.9 °), the phase between the T phase and the R phase Judged as a short circuit accident.
K ₃ = [(20.79) ² + (108.02 × 85/110) ² ] ^1/2
= 86.0 (V) (2-7)
^{_{X 5 = cos -1 (20.79 /}} 110) -cos -1 (20.79 / 86.02)
= 3.09 (°) (2-8)
X ₆ = 60 + 19.1
= 79.1 (°) (2-9)
(4) In the case of a short-circuit accident between the R phase, the S phase, and the T phase The voltage value of the composite voltage V _RS-2T is equal to or less than a predetermined fourth composite voltage value K ₄ = 85 V (75 to 80% of the rated voltage). The phase of the composite voltage V _RS-2T at the time of the short-circuit accident is a predetermined fourth composite voltage angle range ε ₄ (wherein the phase of the composite voltage V _RS-2T at the normal time is 19.1 °. −3.09 ° (= −X ₅ ) ≦ ε ₄ ≦ 7.10 ° (= X ₁ )) (that is, the same phase), and the phase of the short-circuit current I _Ry is predetermined. If it is delayed (+ λ ₄ ) within the fourth short-circuit current angle range λ ₄ (100.9 ° ≦ λ ₄ ≦ 160.9 °), it is determined as a short-circuit accident between the R phase, the S phase, and the T phase.

(Fifth accident mode determination method)
10 is installed on the bus, and the voltage value and phase of the composite voltage V _{R-S + 2T} output from the accident mode determination transformer 120 and the phase of the short-circuit current I _Ry are set. Based on this, the accident aspect is determined as follows.
Here, the secondary side of the accident phase determination transformer 120 has the R phase voltage V _R in the polarity direction, the S phase voltage V _S in the opposite direction, and the T phase voltage V _T in the polarity direction. They are wired so as to be doubled in the direction of synthesis. As a result, the composite voltage V _{R-S + 2T} output from the accident aspect determination transformer 120 is expressed by the following equation.
V _{R−S + 2T} = V _R −V _S + 2V _T
Further, although the impedance angle θ is usually 75 °, the phase angle of the short-circuit current I _Ry is 90 ° (+ 15 °) which is the maximum angle at the time of a short-circuit accident from 30 ° (−45 °) in consideration of arc resistance. ).

(1) In the case of a short-circuit accident between the R phase and the S phase The voltage value of the composite voltage V _{R-S + 2T} is equal to or less than a predetermined fifth composite voltage value K ₅ = 100.1 V (see equation (3-1)) ), And the phase of the composite voltage V _{R-S + 2T} at the normal time is 280.9 °, and the phase of the composite voltage V _{R-S + 2T} at the time of the short-circuit accident is a predetermined fifth composite voltage The angle range ε ₅ (7.10 ° (= X ₇ ) ≦ ε ₅ ≦ 40.9 ° (= X ₈ ), see (3-2) and (3-3))) (− ε ₅ ), and the phase of the short-circuit current I _Ry is advanced only within a predetermined fifth short-circuit current angle range λ ₅ (40.9 ° ≦ λ ₅ ≦ 100.9 °) (−λ ₅ ). It is determined that there is a short circuit accident between the R phase and the S phase.
K ₅ = [(83.15) ² + (72.01 × 85/110) ² ] ^1/2
= 100.1 (V) (3-1)
^{_{X 7 = cos -1 (83.15 /}} 110.0) -cos -1 (83.15 / 110.05)
= 7.10 (°) (3-2)
X ₈ = 280.9-240
= 40.9 (°) (3-3)
(2) In the case of a short circuit accident between the S phase and the T phase The voltage value of the composite voltage V _{R-S + 2T} is equal to or less than a predetermined sixth composite voltage value K ₆ = 86.0 V (see formula (3-4)) ), And the phase of the composite voltage V _{R-S + 2T} at the normal time is 280.9 ° as a reference, the phase of the composite voltage V _{R-S + 2T} at the time of the short-circuit accident is a predetermined sixth composite voltage Angular range ε ₆ (3.09 ° (= X ₉ ) ≦ ε ₆ ≦ 79.1 ° (= X ₁₀ ) (see equations (3-5) and (3-6))) (+ ε ₆ ) and the phase of the short-circuit current I _Ry is advanced only within a predetermined sixth short-circuit current angle range λ ₆ (100.9 ° ≦ λ ₆ ≦ 160.9 °) (−λ ₆ ), It is determined that there is a short circuit accident between the S phase and the T phase.
K ₆ = [(20.79) ² + (108.02 × 85/110) ² ] ^1/2
= 86.0 (V) (3-4)
^{_{X 9 = cos -1 (20.79 /}} 110) -cos -1 (20.79 / 86.02)
= 3.09 (°) (3-5)
X ₁₀ = 360-280.9
= 79.1 (°) (3-6)
(3) In the case of a short-circuit accident between the T phase and the R phase The voltage value of the composite voltage V _{R-S + 2T} is a predetermined seventh composite voltage value K ₇ = 107.6 V or less (see equation (3-7)) ), And the phase of the composite voltage V _{R-S + 2T} at the normal time is 280.9 ° as a reference, the phase of the composite voltage V _{R-S + 2T} at the time of the short-circuit accident is a predetermined seventh composite voltage Angular range ε ₇ (4.12 ° (= X ₁₁ ) ≦ ε ₇ ≦ 19.1 ° (= X ₁₂ ) (see equations (3-8) and (3-9)) (+ ε ₇ ) and the phase of the short-circuit current I _Ry is advanced only within a predetermined seventh short-circuit current angle range λ ₇ (160.9 ° ≦ λ ₇ ≦ 220.9 °) (−λ ₇ ), Judged as a short circuit accident between T phase and R phase.
K ₇ = [103.94 ² + (36.01 × 85/110) ² ] ^1/2
= 107.6 (V) (3-7)
^{_{X 11 = cos -1 (103.94 /}} 110) -cos -1 (103.94 / 107.60)
= 4.12 (°) (3-8)
X ₁₂ = 300-280.9
= 19.1 (°) (3-9)
(4) In the case of a short-circuit accident between the R phase, the S phase, and the T phase, the voltage value of the composite voltage V _{R-S + 2T} is equal to or less than a predetermined eighth composite voltage value K ₈ = 85 V (75 to 80% of the rated voltage) And the phase of the composite voltage V _{R-S + 2T} at the time of a short-circuit accident is a predetermined eighth composite on the basis that the phase of the composite voltage V _{R-S + 2T} at a normal time is 280.9 ° It is within the voltage angle range ε ₈ (−7.10 ° (= −X ₇ ) ≦ ε ₈ ≦ 3.09 ° (= X ₉ )) (that is, in phase), and the short circuit current I _When the phase of _Ry advances only within the predetermined eighth short-circuit current angle range λ ₈ (100.9 ° ≦ λ ₈ ≦ 160.9 °) (−λ ₈ ), between R phase, S phase, and T phase Judged as a short circuit accident.

Next, a direction protection relay device according to a second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 11, the direction protection relay device according to the present embodiment includes a two-phase through current transformer 10 installed in a transmission / distribution line, an instrument transformer 6 installed in a bus, and a two-phase through transformer. R-phase-S-phase line obtained from short-circuit current I _Ry input from flow device 10 and phase voltages V _R , V _S , V _{T of} R-phase, S-phase, and T-phase input from instrument transformer 6 When a short circuit fault is detected on the transmission / distribution line based on the line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR , And a distance relay 20 that collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ installed in the phase and the T phase, respectively.

Here, the two-phase through current transformer 10 is a through-type current transformer in which the R phase and the S phase of the power transmission and distribution line are penetrated in the same direction through an annular core around which a secondary coil is wound. That is, both the R phase and the S phase of the power transmission and distribution line are penetrated in the polarity direction of the two-phase through current transformer 10.
In addition, the R phase of the transmission / distribution line passes through the two-phase through current transformer 10 only once, but the S phase of the transmission / distribution line passes through the two-phase through current transformer 10 twice. As a result, the two-phase through current transformer 10 outputs a sum current of a current flowing through the R phase of the power transmission and distribution line and a current obtained by doubling the current flowing through the S phase.

Therefore, when the load currents flowing in the R-phase, S-phase, and T-phase of the transmission / distribution line are expressed as I _R , I _S , and I _T when no short-circuit accident has occurred, the distance relay from the two-phase through current transformer 10 As in the case of the short-circuit direction relay 4 in the first embodiment described above, the load current I input to the current 20 is a current obtained by doubling the R-phase load current I _R and the S-phase load current I _S ( = 2I _S ), and the amplitude of the load current I is 3 ^1/2 times the amplitude of the R-phase load current I _R (S-phase load current I _S ).
I = I _R + 2I _S
| I | = | I _R + 2I _S | = 3 ^1/2 × | I _R | (= 3 ^1/2 × | I _S |)
Therefore, distance relay 20, to the same as the amplitude of the load current inputted to the first to third distance relay 20 ₁ to 20 ₃ of the prior art shown in FIG. 17, the load current as shown by the following formula The corrected load current I ′ is calculated by multiplying I by 1.
I ′ = I × 1
| I ′ | = | I | × 1− = 3 ^1/2 × | I _R | (= 3 ^1/2 × | I _S |)

In addition, when a short circuit accident occurs in the transmission / distribution line, the short-circuit currents flowing in the R phase, S phase, and T phase of the transmission / distribution line are represented by I _FR , I _FS , I _FT (impedance angle is θ). The distance relay 20 operates as follows according to the accident aspect.
(1) When the short circuit in the case of a short-circuit accident R phase -S phase R phase -S phase occurs, as indicated by broken line arrow in FIG. 11, the short-circuit current I _FR of R-phase to R-phase of transmission and distribution lines There flow inside direction, but the short-circuit current I _FS of S phase to the S phase of the transmission and distribution lines to flow to the outside direction, the T-phase of the transmission and distribution lines does not flow a short-circuit current I _FT T-phase.
Accordingly, the short-circuit current I _Ry input from the two-phase through current transformer 10 to the distance relay 20 is the same as the short-circuit direction relay 4 in the first embodiment described above and the R-phase short-circuit current I _FR . It becomes a vector sum with a current (= 2I _FS ) that is twice the S phase short circuit current I _FS, and the amplitude of the short circuit current I _{Ry is} the amplitude of the S phase short circuit current I _FS (R phase short circuit current I _FR ). (See FIG. 3 (a)).
I _Ry = I _FR + 2I _FS
| I _Ry | = | I _FR + 2I _FS | = | I _FS | (= | I _FR |)
Therefore, distance relay 20, to the same as the amplitude of the short-circuit current which is input to the first to third distance relay 20 ₁ to 20 ₃ of the prior art shown in FIG. 17, the short-circuit current as shown by the following formula by doubling the I _Ry to calculate a correction circuit current I _Ry '.
I _Ry '= I _Ry × 2
| I _Ry '| = | I _Ry | × 2− = 2 × | I _FS | (= 2 × | I _FR |)
The distance relay 20 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR Based on the above, the distance of the accident point and the direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the R phase and S phase of the transmission and distribution line, the accident point is based on the calculated corrected short circuit current I _Ry ′ and the line voltage V _RS between the R phase and S phase (negative polarity). And the direction of the short-circuit current I _Ry are determined (see FIG. 3A).
The distance relay 20 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ when it is determined that a short circuit accident has occurred in the transmission and distribution line.
(2) In the case of a short-circuit accident between the S phase and the T phase When a short circuit accident between the S phase and the T phase occurs, the S phase short circuit current I _FS flows in the S phase of the transmission and distribution line in the internal direction, and the T of the transmission and distribution line Although the T-phase short-circuit current I _FT flows outward in the phase, the R-phase short-circuit current I _FR does not flow in the R-phase of the transmission and distribution line (see FIG. 4).
Therefore, the short-circuit current I _Ry input from the two-phase through current transformer 10 to the distance relay 20 is the same as the short-circuit direction relay 4 in the first embodiment described above, and the S-phase short-circuit current I _FS is The current is doubled (= 2I _FS ), and the amplitude of the short-circuit current I _Ry is twice the amplitude of the S-phase short-circuit current I _FS (see FIG. 3B).
I _Ry = 2I _FS
| I _Ry | = 2 × | I _FS |
Therefore, distance relay 20, to the same as the amplitude of the short-circuit current which is input to the first to third distance relay 20 ₁ to 20 ₃ of the prior art shown in FIG. 17, the short-circuit current as shown by the following formula The corrected short-circuit current I _Ry ′ is calculated by multiplying I _Ry by 1.
I _Ry '= I _Ry × 1
_{| I Ry '| = | I} Ry | × 1 = 2 × | I FS |
The distance relay 20 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR Based on the above, the distance of the accident point and the direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the S phase and the T phase of the transmission and distribution line, the distance of the fault point and the short circuit current based on the calculated corrected short circuit current I _Ry ′ and the line voltage V _ST between the S phase and the T phase. The direction of I _Ry is determined (see FIG. 3B).
The distance relay 20 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ when it is determined that a short circuit accident has occurred in the transmission and distribution line.
(3) In the case of a short circuit accident between the T phase and the R phase When a short circuit accident occurs between the T phase and the R phase, a T phase short circuit current I _FT flows in the T phase of the transmission and distribution line, and the R of the transmission and distribution line. While the short-circuit current I _FR of R-phase to phase flows to the outside direction, the S-phase of the transmission and distribution lines does not flow a short-circuit current I _FS of S phase (see FIG. 5).
Accordingly, the short-circuit current I _Ry input from the two-phase through current transformer 10 to the distance relay 20 becomes the R-phase short-circuit current I _{FR in the same} manner as in the case of the short-circuit direction relay 4 in the first embodiment described above. The amplitude of the short-circuit current I _{Ry is} the amplitude of the R-phase short-circuit current I _FR (see FIG. 3C).
I _Ry = I _FR
| I _Ry | = | I _FR |
Therefore, distance relay 20, to the same as the amplitude of the short-circuit current which is input to the first to third distance relay 20 ₁ to 20 ₃ of the prior art shown in FIG. 17, the short-circuit current as shown by the following formula by doubling the I _Ry to calculate a correction circuit current I _Ry '.
I _Ry '= I _Ry × 2
| I _Ry '| = | I _Ry | × 2 = 2 × | I _FR |
The distance relay 20 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR Based on the above, the distance of the accident point and the direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the T phase and the R phase of the transmission and distribution line, the accident point is based on the calculated corrected short circuit current I _Ry ′ and the line voltage V _TR (negative polarity) between the T phase and the R phase. And the direction of the short-circuit current I _Ry are determined (see FIG. 3C).
The distance relay 20 collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ when it is determined that a short circuit accident has occurred in the transmission and distribution line.
(4) In the case of a short circuit accident between R phase, S phase, and T phase When a short circuit accident between R phase, S phase, and T phase occurs, short circuit current I of R phase to R phase, S phase, and T phase of the transmission and distribution line _FR , S-phase short-circuit current I _FS and T-phase short-circuit current I _FT flow in the internal direction with a phase difference of 120 degrees (see FIG. 6).
Accordingly, the short-circuit current I _Ry input from the two-phase through current transformer 10 to the distance relay 20 is the same as the short-circuit direction relay 4 in the first embodiment described above and the R-phase short-circuit current I _FR . It becomes a vector sum with a current (= 2I _FS ) twice the S phase short circuit current I _FS, and the amplitude of the short circuit current I _Ry is 3 of the amplitude of the R phase short circuit current I _FR (S phase short circuit current I _FS ). the ^1/2 (see FIG. 3 (d)).
I _Ry = I _FR + 2I _FS
| I _Ry | = | I _FR + 2I _FS | = 3 ^1/2 × | I _FR | (= 3 ^1/2 × | I _FS |)
Therefore, distance relay 20, to the same as the amplitude of the short-circuit current which is input to the first to third distance relay 20 ₁ to 20 ₃ of the prior art shown in FIG. 17, the short-circuit current as shown by the following formula The corrected short-circuit current I _Ry ′ is calculated by multiplying I _Ry by 1.
I _Ry '= I _Ry × 1
| I _Ry '| = | I _Ry | × 1− = 3 ^1/2 × | I _FR | (= 3 ^1/2 × | I _FS |)
Further, since the short circuit current I _Ry is input from the two-phase through current transformer 10 to the distance relay 20 with a delay phase of 30, the distance relay 20 also performs phase correction of the corrected short circuit current I _Ry '.
The distance relay 20 includes a phase-corrected short-circuit current I _Ry ′, an R-phase / S-phase line voltage V _RS , an S-phase / T-phase line voltage V _ST, and a T-phase / R-phase line voltage V _TR. Based on the above, the distance of the accident point and the direction of the short-circuit current I _Ry are determined. In the case of a short circuit accident between the R phase, the S phase, and the T phase of the transmission and distribution line, the fault point is determined based on the corrected short circuit current I _Ry ′ corrected in phase and the line voltage V _TR between the T phase and the R phase. The distance and the direction of the short-circuit current I _Ry are determined (see FIG. _3D ).
Distance relay 20 is collectively cut off when it is determined that the short-circuit accident occurs the first to third circuit breaker 2 ₁ to 2 ₃ of the transmission and distribution lines.

The distance relay 20 calculates the accident point distance by obtaining the correction voltage V _Ry as described below when determining the accident aspect using the first accident aspect determination method described above.
(1) In case of short-circuit accident between R phase and S phase R-phase and S-phase line voltage V _RS obtained from R-phase and S-phase voltage V _R , V _S input from instrument transformer 6 The correction voltage is V _Ry .
V _Ry = V _RS
(2) In the case of a short-circuit accident between the S phase and the T phase The S-phase and T-phase line voltage V _ST obtained from the S-phase and T-phase phase voltages V _S and V _T input from the instrument transformer 6 The correction voltage is V _Ry .
V _Ry = V _ST
(3) In the case of a short-circuit accident between the T phase and the R phase The line voltage V _TR between the T phase and the R phase obtained from the phase voltages V _T and V _{R of the} T phase and the R phase input from the instrument transformer 6 The correction voltage is V _Ry .
V _Ry = V _TR
(4) In case of short-circuit accident between R phase, S phase and T phase Line voltage between T phase and R phase obtained from phase voltages V _T and V _{R of} T phase and R phase input from instrument transformer 6 Let V _TR be the correction voltage V _Ry .
V _Ry = V _TR

Further, when determining the accident aspect using the above-described second or third accident aspect determination method, the distance relay 20 receives the phase voltage V _T of the T phase and the R phase input from the instrument transformer 6. , V _R , using the T-phase to R-phase line voltage V _TR (see FIG. 2B), the correction voltage V _Ry is calculated as follows to calculate the distance of the accident point. . Note that V = V _TR ∠ (210 ° + α).
(1) In case of short circuit accident between R phase and S phase V _Ry = 2 × V × cos (60 ° + α)
(2) In case of short-circuit accident between S phase and T phase V _Ry = 2 × V × cos (60 ° + α)
(3) In case of short-circuit accident between T phase and R phase V _Ry = V
(4) In case of short circuit between R phase, S phase and T phase V _Ry = V

The distance relay 20 uses the composite voltage V _RS-2T input from the accident aspect determination transformer 110 to determine the accident aspect using the above-described fourth accident aspect determination method. The distance of the accident point is calculated by _obtaining the correction voltage V _Ry as shown in FIG. Thereby, the instrument transformer 6 can be made unnecessary.
(1) In case of short-circuit accident between R phase and S phase V _Ry = V _RS-2T × (168/110)
(2) In case of short circuit between S phase and T phase V _Ry = V _RS-2T × 2 × (168/110)
(3) In case of short-circuit accident between T phase and R phase V _Ry = V _RS-2T × (2/3) × (168/110)
(4) In the case of a short circuit accident between R phase, S phase and T phase V _Ry = V _RS-2T × (3 ^1/2 / 7 ^1/2 ) × (68/110)

The distance relay 20 uses the composite voltage V _{R-S + 2T} input from the accident aspect determination transformer 120 when determining the accident aspect using the fifth accident aspect determination method described above. Then, the distance of the accident point is calculated by _obtaining the correction voltage V _Ry as shown below. Thereby, the instrument transformer 6 can be made unnecessary.
(1) In the case of a short-circuit accident between the R phase and the S phase V _Ry = 110 × (V _{R−S + 2T} −83.15) /26.85
(2) In the case of a short circuit accident between the S phase and the T phase V _Ry = 110 × (V _{R−S + 2T} −20.79) /89.21
(3) In the case of a short-circuit accident between the T phase and the R phase V _Ry = 110 × (V _{R−S + 2T} −103.94) /6.06
(4) In case of short circuit between R phase, S phase and T phase V _Ry = V _{R-S + 2T}

  The two-phase through-current transformer 10 penetrates the R phase of the transmission / distribution line once and the S phase twice, but penetrates the S phase of the transmission / distribution line once and the T phase twice. It may be penetrated, or the T phase of the transmission / distribution line may be penetrated once and the R phase may be penetrated twice.

However, according to the CT connection, the distance relay 20 calculates the corrected short-circuit current I _Ry ′ at the magnification shown in Table 7 according to the accident situation, and between the calculated corrected short-circuit current I _Ry ′ and the line shown in Table 2 Based on the voltage, the distance of the fault point and the direction of the short-circuit current I _Ry are discriminated to determine whether or not a short-circuit fault has occurred in the transmission and distribution line.

Next, a directional protection relay device according to a third embodiment of the present invention will be described with reference to FIG.
Direction protective relay apparatus according to this embodiment, as shown in FIG. 12, a first two-phase through current transformer 10 ₁ installed in the first transmission and distribution lines 1L equilibrium two-line transmission and distribution lines, the equilibrium the second two-phase through current transformer 10 ₂ installed in the second transmission and distribution lines 2L two-line transmission and distribution lines, and instrument transformer 6 installed to the bus, the first two-phase through current transformer From the difference between the short-circuit current input from the instrument 10 ₁ and the short-circuit current input from the second two-phase through current transformer 10 ₂ (hereinafter referred to as “short-circuit current I _Ry ”) and the instrument transformer 6 R-phase to S-phase line voltage V _RS obtained from input R-phase, S-phase and T-phase phase voltages V _R , V _S and V _T , S-phase to T-phase line voltages V _ST and T the first or second transmission and distribution lines 1L based on the line voltage V _TR phase -R phase, upon detecting a short circuit of 2L, the first and second transmission and distribution lines 1L, among 2L Circuit breakers (R phase, S phase, and T phase of the first transmission / distribution line 1L) installed in the R phase, S phase, and T phase of the person who has the fault (hereinafter referred to as "accident line") _1st to _3rd circuit breakers 2 ₁ to 2 ₃ respectively installed in the 4th to 6th circuit breakers 2 respectively installed in the R phase, S phase and T phase of the second transmission and distribution line 2L _{4 to} 2 ₆ ) and a line selection relay 30 that collectively cuts off.

Here, the first two-phase through current transformer 10 _1, the first transmission and distribution lines 1L of R-phase and feedthrough current transformer which is passed through the S-phase in the same direction in an annular core formed by winding a secondary coil It is a vessel. Ie, R-phase and S-phase of the first transmission and distribution lines 1L are both through the first two-phase through polarity direction of the current transformer 10 _1.
In addition, R-phase of the first transmission and distribution lines 1L is through only the first two-phase through current transformer 10 ₁ once but, S-phase of the first transmission and distribution lines 1L is about twice the first It extends through the two-phase through current transformer 10 _1. Thus, from the first two-phase through current transformer 10 _1, the sum current of the first current obtained by doubling the current flowing through the current and the S phase through the R-phase of the transmission and distribution lines 1L is outputted.
Similarly, the second two-phase through current transformer 10 _2, the annular core formed by winding a secondary coil second transmission and distribution lines 2L of R-phase and feedthrough current transformer which is passed through the S-phase in the same direction It is a vessel. Ie, R-phase and S-phase of the second transmission and distribution lines 2L are both through the second two-phase through current transformer 10 _second polarity direction.
In addition, R-phase of the second transmission and distribution lines 2L is through only the second two-phase through current transformer 10 ₂ once, but, S-phase of the second transmission and distribution lines 2L is about twice the second It extends through the two-phase through current transformer 10 _2. Thus, from the second two-phase through current transformer _102, the sum current of the second current obtained by doubling the current flowing through the current and the S phase through the R-phase of the transmission and distribution lines 2L is outputted.
In addition, the second two-phase through current transformer 10 ₂ has a polarity of the short-circuit current input from the second two-phase through current transformer 10 ₂ to the line selection relay 30 in the first two-phase through current transformer 10. _The line selection relay 30 is connected so that the polarity of the short circuit current input from ₁ to the line selection relay 30 is reversed.

Therefore, the load current flowing in the R phase, S phase, and T phase of the first transmission / distribution line 1L when no short circuit accident has occurred is represented by I _R1 , I _S1 , I _T1 and the second transmission / distribution line 2L. When the load currents flowing in the R phase, S phase, and T phase are represented by I _R2 , I _S2 , and I _T2 , the load current i ₁ that is input from the first two-phase through current transformer 10 ₁ to the line selection relay 30. Is the vector sum of the R-phase load current I _R1 and the current obtained by doubling the S-phase load current I _S1 (= 2I _S1 ), as in the case of the short-circuit direction relay 4 in the first embodiment described above. Thus, the amplitude of the load current i ₁ is 3 ^1/2 times the amplitude of the R-phase load current I _R1 (S-phase load current I _S1 ).
i ₁ = I _R1 + 2I _S1
| I ₁ | = | I _R1 + 2I _S1 | = 3 ^1/2 × | I _R1 | (= 3 ^1/2 × | I _S1 |)
Similarly, the load current i ₂ input from the second two-phase through current transformer 10 ₂ to the line selection relay 30 is a current obtained by doubling the R-phase load current I _R2 and the S-phase load current I _S2 (= The polarity of the vector sum with 2I _S2 ) is inverted, and the amplitude of the load current i ₂ is 3 ^1/2 times the amplitude of the R-phase load current I _R2 (S-phase load current I _S2 ).
i ₂ = − (I _R2 + 2I _S2 )
| I ₂ | = | I _R2 + 2I _S2 | = 3 ^1/2 × | I _R2 | (= 3 ^1/2 × | I _S2 |)
As a result, the load current I input to the line selection relay 30 is a vector sum of the load current i ₁ and the load current i _2, and the amplitude of the load current I is “0” (I = i ₁ + i ₂ = 0). ).
In order to make the line selection relay 30 the same as the amplitude of the load current input to the conventional _first to _third line selection relays 30 ₁ to 30 ₃ shown in FIG. The corrected load current I ′ is calculated by multiplying the load current I by 1/3 ^1/2 .
I ′ = I × 1/3 ^1/2
| I '| = | I | × 1/3 1/ ^2-

In addition, when a short circuit accident occurs in the first or second transmission / distribution lines 1L, 2L, the short-circuit current flowing in the R phase, S phase, and T phase of the first and second transmission / distribution lines 1L, 2L is expressed as I _FR , I _FS , I _FT (impedance angle is θ), the line selection relay 30 operates as follows according to the aspect of the accident.
(1) In the case of a short circuit accident between the R phase and the S phase When a short circuit accident between the R phase and the S phase occurs, the R of the first and second transmission / distribution lines 1L and 2L, as shown by the dashed arrows in FIG. An R-phase short-circuit current _IFR flows in the internal direction, and an S-phase short-circuit current _IFS flows in the S-phase of the first and second transmission and distribution lines 1L and 2L. The T-phase short circuit current I _FT does not flow in the T-phase of the transmission and distribution lines 1L and 2L.
Therefore, the short-circuit current I _Ry input to the line selection relay 30 is the same as that of the short-circuit direction relay 4 in the first embodiment described above, and the R-phase short-circuit current I _FR (the first transmission / distribution line 1L). The short-circuit current flowing in the R phase of the second and the short-circuit current flowing in the R-phase of the second transmission and distribution line 2L) and the S-phase short-circuit current I _FS (the short-circuit current flowing in the S-phase of the first transmission and distribution line 1L) And the current sum (= 2I _FS ) that is twice the difference between the short circuit current flowing in the S phase of the second transmission / distribution line 2L and the amplitude of the short circuit current I _Ry is the S phase short circuit current I _FS (R phase short-circuit current I _FR ) amplitude (see FIG. 3A).
I _Ry = I _FR + 2I _FS
| I _Ry | = | I _FR + 2I _FS | = | I _FS | (= | I _FR |)
Therefore, in order to make the line selection relay 30 the same as the amplitude of the short-circuit current input to the conventional _first to _third line selection relays 30 ₁ to 30 ₃ shown in FIG. The corrected short-circuit current I _Ry 'is calculated by multiplying the short-circuit current I _Ry by 1.
I _Ry '= I _Ry × 1
| I _Ry '| = | I _Ry | × 1− = | I _FS | (= | I _FR |)
The line selection relay 30 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR. Based on the above, the accident line is determined. In the case of a short-circuit accident between the R-phase and S-phase of the first or second transmission / distribution lines 1L, 2L, the calculated corrected short-circuit current I _Ry 'and the R-S-phase line voltage V _RS (polarity Is negative), the accident line is determined (see FIG. 3A).
When the line selection relay 30 determines that a short-circuit accident has occurred in the first transmission / distribution line 1L, the line selection relay 30 disconnects the _first to _third circuit breakers 2 ₁ to 2 _{3 all} together, and the second transmission / distribution line 2L If it is determined that a short circuit accident has occurred, the _fourth to _sixth circuit breakers 2 ₄ to 2 ₆ are collectively disconnected.
(2) In the case of a short circuit accident between the S phase and the T phase When a short circuit accident between the S phase and the T phase occurs, the S phase short circuit current I _FS is internally contained in the S phase of the first and second power transmission lines 1L and 2L. The T-phase short circuit current I _FT flows outward in the T phase of the first and second transmission / distribution lines 1L, 2L, but the R phase of the first and second transmission / distribution lines 1L, 2L. No R-phase short-circuit current I _FR flows (see FIG. 4).
Therefore, short-circuit current I _Ry input to the line selection relay 30, as in the case of the short-circuit direction relay 4 in the first embodiment described above, the short-circuit current of the S-phase I _FS (first transmission and distribution lines 1L The difference between the short-circuit current flowing in the S-phase and the short-circuit current flowing in the S-phase of the second transmission / distribution line 2L is doubled (= 2I _FS ), and the amplitude of the short-circuit current I _Ry is the short-circuit of the S-phase This is twice the amplitude of the current I _FS (see FIG. 3B).
I _Ry = 2I _FS
| I _Ry | = 2 × | I _FS |
Therefore, in order to make the line selection relay 30 the same as the amplitude of the short-circuit current input to the conventional _first to _third line selection relays 30 ₁ to 30 ₃ shown in FIG. The short-circuit current I _Ry is halved to calculate a corrected short-circuit current I _Ry '.
I _Ry '= I _Ry × 1/2
| I _Ry '| = | I _Ry | × 1/2 = | I _FS |
The line selection relay 30 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR. Based on the above, the accident line is determined. In the case of a short circuit accident between the S-phase and the T-phase of the first or second transmission / distribution lines 1L, 2L, the calculated corrected short-circuit current I _Ry ′ and the S-line-T line voltage V _ST Based on this, the accident line is determined (see FIG. 3B).
When the line selection relay 30 determines that a short-circuit accident has occurred in the first transmission / distribution line 1L, the line selection relay 30 disconnects the _first to _third circuit breakers 2 ₁ to 2 _{3 all} together, and the second transmission / distribution line 2L If it is determined that a short circuit accident has occurred, the _fourth to _sixth circuit breakers 2 ₄ to 2 ₆ are collectively disconnected.
(3) In the case of a short circuit accident between the T phase and the R phase When a short circuit accident occurs between the T phase and the R phase, the T phase short circuit current I _FT is internally generated in the T phase of the first and second power transmission lines 1L and 2L. The R-phase short-circuit current _IFR flows to the R phase of the first and second transmission and distribution lines 1L and 2L, but flows to the S phase of the first and second transmission and distribution lines 1L and 2L. No S-phase short-circuit current I _FS flows (see FIG. 5).
Therefore, the short-circuit current I _Ry input to the line selection relay 30 is the same as that of the short-circuit direction relay 4 in the first embodiment described above, and the R-phase short-circuit current I _FR (the first transmission / distribution line 1L). 3) and the amplitude of the short-circuit current I _{Ry is} the amplitude of the R-phase short-circuit current I _FR (FIG. 3). (See (c)).
I _Ry = I _FR
| I _Ry | = | I _FR |
Therefore, in order to make the line selection relay 30 the same as the amplitude of the short-circuit current input to the conventional _first to _third line selection relays 30 ₁ to 30 ₃ shown in FIG. The corrected short-circuit current I _Ry 'is calculated by multiplying the short-circuit current I _Ry by 1.
I _Ry '= I _Ry × 1
| I _Ry '| = | I _Ry | × 1 = | I _FR |
The line selection relay 30 includes the calculated corrected short-circuit current I _Ry ′, the R-phase / S-phase line voltage V _RS , the S-phase / T-phase line voltage V _ST, and the T-phase / R-phase line voltage V _TR. Based on the above, the accident line is determined. In the case of a short-circuit accident between the T-phase and R-phase of the first or second transmission / distribution lines 1L, 2L, the calculated corrected short-circuit current I _Ry ′ and the T-phase-R phase line voltage V _TR (polarity Is negative), the accident line is determined (see FIG. 3C).
When the line selection relay 30 determines that a short-circuit accident has occurred in the first transmission / distribution line 1L, the line selection relay 30 disconnects the _first to _third circuit breakers 2 ₁ to 2 _{3 all} together, and the second transmission / distribution line 2L If it is determined that a short circuit accident has occurred, the _fourth to _sixth circuit breakers 2 ₄ to 2 ₆ are collectively disconnected.
(4) In the case of a short circuit accident between the R phase, the S phase, and the T phase When a short circuit accident between the R phase, the S phase, and the T phase occurs, the R phase, the S phase, and the first and second power transmission lines 1L and 2L An R-phase short-circuit current I _FR , an S-phase short-circuit current I _FS and a T-phase short-circuit current I _FT flow in the T phase in the internal direction with a phase difference of 120 ° (see FIG. 6).
Therefore, short-circuit current I _Ry input to the line selection relay 30, as in the case of the short-circuit direction relay 4 in the first embodiment described above, a short circuit of the R-phase current I _FR (first transmission and distribution lines 1L The short-circuit current flowing in the R phase of the second and the short-circuit current flowing in the R-phase of the second transmission and distribution line 2L) and the S-phase short-circuit current I _FS (the short-circuit current flowing in the S-phase of the first transmission and distribution line 1L) And the current sum (= 2I _FS ) that is twice the difference between the short-circuit current flowing in the S-phase of the second transmission / distribution line 2L, and the amplitude of the short-circuit current I _Ry is the R-phase short-circuit current I _FR 3 ^1/2 times the amplitude of the S-phase short-circuit current I _FS (see FIG. 3D).
I _Ry = I _FR + 2I _FS
| I _Ry | = | I _FR + 2I _FS | = 3 ^1/2 × | I _FR | (= 3 ^1/2 × | I _FS |)
Therefore, in order to make the line selection relay 30 the same as the amplitude of the short-circuit current input to the conventional _first to _third line selection relays 30 ₁ to 30 ₃ shown in FIG. The short-circuit current I _Ry is multiplied by 1/3 ^1/2 to calculate a corrected short-circuit current I _Ry '.
I _Ry '= I _Ry × 1/3 ^1/2
_{| I Ry '| = | I} Ry | × 1/3 1/2 - = | I FR | (= | I FS |)
Further, since the short circuit current I _Ry is input from the two-phase through current transformer 10 to the line selection relay 30 with a delayed phase of 30 °, the line selection relay 30 also performs phase correction of the corrected short circuit current I _Ry ′.
The line selection relay 30 includes a phase-corrected short circuit current I _Ry ′, an R-phase / S-phase line voltage V _RS , an S-phase / T-phase line voltage V _ST, and a T-phase / R-phase line voltage V Determine the accident line based on _TR . In the case of a short-circuit accident between the R phase, the S phase, and the T phase of the first or second transmission and distribution lines 1L, 2L, the phase correction short circuit current I _Ry ′ and the line voltage V _TR between the T phase and the R phase. Based on the above, the accident line is determined (see FIG. 3D).
When the line selection relay 30 determines that a short-circuit accident has occurred in the first transmission / distribution line 1L, the line selection relay 30 disconnects the _first to _third circuit breakers 2 ₁ to 2 _{3 all} together, and the second transmission / distribution line 2L If it is determined that a short circuit accident has occurred, the _fourth to _sixth circuit breakers 2 ₄ to 2 ₆ are collectively disconnected.

Note that the first two-phase through current transformer 10 ₁ was passed through the S-phase 2 times with pass through once R-phase of the first transmission and distribution lines 1L, S of the first transmission and distribution lines 1L The phase may be penetrated once and the T phase may be penetrated twice, or the T phase of the first power distribution line 1L may be penetrated once and the R phase may be penetrated twice.
The same applies to the second two-phase through current transformer 10 ₂ .

However, according to the CT connection, the line selection relay 30 causes the correction short-circuit current I _Ry at the magnification shown in Table 1 according to the accident aspect determined using any of the first to fifth accident aspect determination methods described above. ' _Is calculated, and the _fault line is determined based on the calculated corrected short-circuit current I _Ry ' and the line voltage shown in Table 2, and a short-circuit _fault occurs in the first or second power distribution line 1L, 2L. It is determined whether or not it has occurred.

Next, a power direction relay device according to an embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 13, the power direction relay device according to the present embodiment includes a two-phase through current transformer 10 installed in a transmission and distribution line, an instrument transformer 6 installed in a bus, and a two-phase through transformer. The current i _Ry input from the flow device 10 and the reference voltage obtained from the voltage information (R-phase, S-phase, and T-phase phase voltages V _R , V _S , V _T ) input from the instrument transformer 6. When a reverse power flow is detected based on this, a power direction relay 40 that collectively cuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ installed in the R phase, S phase, and T phase of the transmission and distribution lines is provided. .

Here, the two-phase through current transformer 10 is a through-type current transformer in which the R phase and the S phase of the power transmission and distribution line are penetrated in the same direction through an annular core around which a secondary coil is wound. That is, both the R phase and the S phase of the power transmission and distribution line are penetrated in the polarity direction of the two-phase through current transformer 10.
In addition, the R phase of the transmission / distribution line passes through the two-phase through current transformer 10 only once, but the S phase of the transmission / distribution line passes through the two-phase through current transformer 10 twice. As a result, the two-phase through current transformer 10 outputs a sum current of a current flowing through the R phase of the power transmission and distribution line and a current obtained by doubling the current flowing through the S phase.

When reverse power flow occurs in the transmission / distribution line, effective currents i _RP , i _SP , i _TP flow in the + direction in the R-phase, S-phase, and T-phase of the transmission / distribution line, as indicated by the dashed arrows in FIG.
At this time, the R-phase effective current i _RP and the S-phase effective current i _{SP of the} power transmission / distribution line are obtained by changing the annular core of the two-phase through current transformer 10 with a phase difference of 120 ° as shown in FIG. Since the current flows through the polarity direction, the effective current i _RyP included in the current i _Ry input from the two-phase through current transformer 10 to the power direction relay 40 is represented by a solid thick arrow R in FIG. The vector sum of the effective current i _RP of the phase and the current (2i _SP ) that is twice the effective current i _SP of the S phase, and the amplitude of the effective current i _RyP is the effective current i _RP of the R phase (the effective current i of the S phase _SP ) is 3 ^1/2 times the amplitude (see FIG. 14A).
i _RyP = i _RP + 2i _SP
| I _RyP | = | i _RP + 2i _SP | = 3 ^1/2 × | i _RP | (= 3 ^1/2 × | i _SP |)
Therefore, in order to make the power direction relay 40 have the same amplitude as the effective current input to the conventional _first to _third power direction relays 40 ₁ to 40 ₃ shown in FIG. The correction current i _Ry 'is calculated by multiplying the current i _Ry by 1/3 ^1/2 .
i _Ry '= i _Ry × 1/3 ^1/2
| I _Ry '| = | i _Ry | × 1/3 ^1/2
(| I _RyP '| = | i _RP | (= | i _SP |))
The power direction relay 40 uses the R-phase phase voltage V _R input from the instrument transformer 6 as a reference voltage, and calculates the corrected current i _Ry ′ and the reference voltage (R-phase phase voltage V _R ). When the correction effective current i _RyP ′ included in the correction current i _Ry ′ enters the operation range as shown by the dashed arrow in FIG. The third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.

Although the phase voltage V _R of the R phase is used as the reference voltage, the phase voltage V _ST of the S phase / T phase advanced by 90 ° may be used.

The two-phase through current transformer 10 penetrates the R phase of the transmission / distribution line once and the S phase twice, but penetrates the S phase of the transmission / distribution line once and the T phase twice. It may be allowed to penetrate, or the T phase of the transmission / distribution line may be penetrated once and the R phase may be penetrated twice.
However, the CT connection, power directional relay 40, the reference voltage of the current i _Ry inputted from the two-phase through current transformer 10 1/3 ^1/2 times a correction current i _Ry 'obtained by correcting shown in Table 8 And work on the basis of. In Table 8, “+” in the CT connection indicates that the polarity of the current output from the two-phase through current transformer 10 is “+” when the direction of the current flowing through each phase of the transmission / distribution line is the + direction. Indicates that

  Further, by operating the power direction relay 40 as follows, the power direction relay 40 can function as a reactive power direction relay (DQ).

When a reverse power flow occurs in the transmission / distribution line, reactive currents i _RQ , i _SQ , i _TQ flow in the + direction in the R phase, S phase, and T phase of the transmission / distribution line, respectively.
At this time, the R-phase reactive current i _RQ and the S-phase reactive current i _{SQ of} the transmission / distribution line are formed by the annular core of the two-phase through current transformer 10 with a phase difference of 120 ° as shown in FIG. Since it flows through in the polar direction, the reactive current i _RyQ included in the current i _Ry input from the two-phase through current transformer 10 to the power direction relay 40 is the R-phase reactive current i _RQ and the S-phase reactive current i. It becomes a vector sum with the current (2i _SQ ) that is twice the _SQ, and the amplitude of the reactive current i _RyQ is 3 ^1/2 times the amplitude of the R-phase reactive current i _RQ (S-phase reactive current i _SQ ) ( (See FIG. 15 (a)).
i _RyQ = i _RQ + 2i _SQ
| I _RyQ | = | i _RQ + 2i _SQ | = 3 ^1/2 × | i _RQ | (= 3 ^1/2 × | i _SQ |)
Therefore, the power direction relay 40 calculates the correction current i _Ry ′ by multiplying the current i _Ry by 1/3 ^{1/2 as} shown in the following equation.
i _Ry '= i _Ry × 1/3 ^1/2
_{| I Ry '| = | i} Ry | × 1/3 1/2 -
(| I _RyQ '| = | i _RQ | (= | i _SQ |))
The electric power direction relay 40 is the polarity of the line voltage V _ST of the S phase-T phase obtained from the phase voltages V _R , V _S , V _{T of the} R phase, S phase and T phase input from the instrument transformer 6. Is operated based on the calculated correction current i _Ry ′ and the reference voltage (S-phase to T-phase line voltage V _ST having a negative polarity) using the inverted version (−V _ST ) as a reference voltage. (Maximum sensitivity angle = 90 °) When the correction reactive current i _RyQ ′ included in the correction current i _Ry ′ enters the operating range as shown by the dashed arrow in FIG. Blocks 2 _{1 to} 2 ₃ at _once .

Note that the S-phase to T-phase line voltage V _ST having a negative polarity is used as the reference voltage, but a phase phase of the R-phase phase voltage −V _R advanced by 90 ° may be used.

  In the above description, the two-phase through current transformer is made to penetrate the R phase once and the S phase twice, but the number of times the R phase and the S phase are made to penetrate the two-phase through current transformer is m. Times and n times (m ≠ n).

Further, in the fourth accident mode determination method described above, the R-phase phase voltage V _R is 2 in the polarity direction, the S-phase phase voltage V _S is in the opposite polarity direction, and the T-phase phase voltage V _T is 2 in the opposite polarity direction. The secondary side of the accident aspect determination transformer 110 is connected so as to be combined, and in the fifth accident aspect determination method described above, the phase voltage V _R of the R phase is in the polarity direction and the phase voltage V of the S phase. _The secondary side of the accident mode determination transformer 120 is connected so that _S is antipolar and the T phase voltage V _T is doubled in the polarity direction to synthesize, but the R phase voltage V _R is Multiply a in the polar or antipolar direction by a, multiply the S phase voltage V _S in the polar or antipolar direction by b, and multiply the T phase voltage V _T in the polar or antipolar direction by c The secondary side of the accident mode determination transformer may be connected so as to be combined. The composite voltage V _{aR + bS + cT} output from this accident aspect determination transformer is expressed by the following equation.
V _{aR + bS + cT} = ± aV _R ± bV _S ± cV _T

Further, in the short-circuit direction relay 4, the distance relay 20, and the line selection relay 30, the phase of the short-circuit current I _Ry is corrected in the short-circuit accident between the R phase, the S phase, and the T phase. This is to approximate the conventional directional characteristics. Therefore, the direction characteristics may be changed instead of phase correction.

  In addition, the two-phase through current transformer has been described in combination with the direction protection relay and power direction relay used in the transmission and distribution lines, but the two-phase through current transformer is used in three-phase AC circuits other than the transmission and distribution lines. The same effect can be obtained by combining with a directional protection device or a power direction relay.

It is a figure for demonstrating the direction protection relay apparatus by 1st Example of this invention. It is a diagram for explaining the load current I and the T-phase -R phase phase voltage V _R of the line voltage V _TR and R-phase when a short circuit does not occur. It is a figure for demonstrating short circuit current _IRy input into the short circuit direction relay 4 from the two-phase through current transformer 10 shown in FIG. 1 when a short circuit accident generate | occur | produces. It is a figure for demonstrating the short circuit current _IRy input into the short circuit direction relay 4 from the two-phase through current transformer 10 when the short circuit accident generate | occur | produces between the S phase-T phases of the power transmission and distribution line shown in FIG. . It is a figure for demonstrating the short circuit current _IRy input into the short circuit direction relay 4 from the two-phase through current transformer 10 when the short circuit accident generate | occur | produces between T phase-R phases of the power transmission and distribution line shown in FIG. . The short circuit current I _Ry input from the two-phase through current transformer 10 to the short circuit direction relay 4 when a short circuit accident occurs between the R phase, the S phase, and the T phase of the transmission and distribution line shown in FIG. FIG. It is a figure for demonstrating the 2nd accident aspect determination method. It is a figure for demonstrating the 3rd accident aspect determination method. It is a figure which shows the structure of the transformer 110 for an accident aspect determination used in the 4th accident aspect determination method. It is a figure which shows the structure of the transformer 120 for accident aspect determination used in the 5th accident aspect determination method. It is a figure for demonstrating the direction protection relay apparatus by 2nd Example of this invention. It is a figure for demonstrating the direction protection relay apparatus by the 3rd Example of this invention. It is a figure for demonstrating the electric power direction relay apparatus by one Example of this invention. It is a figure for demonstrating operation | movement of the electric power direction relay 40 shown in FIG. It is a figure for demonstrating operation | movement of the electric power direction relay 40 shown in FIG. 13 when making it function as a reactive power relay. It is a figure for demonstrating the conventional short circuit direction relay. It is a figure for demonstrating the conventional distance relay. It is a figure for demonstrating the conventional line selection relay. It is a figure for demonstrating the conventional electric power direction relay. It is a diagram for explaining a first operation of the power directional relay 40 ₁ of prior art shown in FIG. 19.

1 Power supply 2 _{1 to} 2 _{6 1st} to _6th circuit breakers 3 _{1 to} 3 _{6 1st} to _6th current transformer 4 Short circuit direction relays 4 ₁ to 4 _{3 1st} to _3rd short circuit direction relays 6 Transformer 10 Two-phase through current transformers 10 ₁ and 10 ₂ First and second two-phase through current transformers 20 Distance relays 20 _{1 to} 20 ₃ First to third distance relays 30 Line selection relays 30 ₁ to 30 ₃ First to third line selection relays 40 Power direction relays 40 ₁ to 40 ₃ First to _third power direction relays 1L, 2L First and second transmission and distribution lines I, I _R , I _S , I _T I _R1 , I _S1 , I _T1 , I _R2 , I _S2 , I _T2 , i ₁ , i ₂ Load current I ′ corrected load current I _Ry , I _FR , I _FS , I _FT short circuit current I _Ry ′ corrected short circuit current V _R , V _S , V _T phase voltage V _RS , V _ST , V _TR line voltage V _Ry correction voltage θ impedance angle i _RP , i _SP , i _TP , i _RyP effective current i _RQ , i _{S Q} , i _TQ , i _RyQ reactive current i _Ry current i _Ry 'corrected current i _RyP ' corrected effective current i _RyQ 'corrected reactive current G power generation equipment L load

Claims (15)

A directional protection relay device for protecting a three-phase AC circuit from a short circuit accident,
A two-phase through current transformer in which an arbitrary two phases of the three-phase AC circuit are penetrated in the same direction by a different number of times through an annular core wound with a secondary coil;
When a short-circuit fault is detected based on the short-circuit current input from the two-phase through current transformer and the voltage information of the three-phase AC circuit, the circuit breakers installed in each phase of the three-phase AC circuit are collectively shut off. A directional protection relay,
A directional protection relay device comprising:   The direction protection relay further comprises an accident mode determination unit that determines an accident mode of a short circuit accident of the three-phase AC circuit, and the short circuit current input from the two-phase through current transformer includes the fault mode determination unit. When a corrected short circuit current is calculated by multiplying a predetermined multiple according to the determination result of the accident aspect, and a short circuit accident is detected based on the calculated corrected short circuit current and voltage information of the three phase AC circuit, the three phase AC circuit The directional protection relay device according to claim 1, wherein the circuit breakers installed in each phase are collectively cut off. The accident mode determination means determines whether the three-phase AC circuit has three line voltages (V _RS , V _ST , V _TR ), three phase voltages (V _R , V _S , V _T ), or a phase / line voltage. The direction protection relay device according to claim 2, wherein an accident aspect of a short circuit accident of the three-phase AC circuit is determined based on the basis. The accident mode determination means is based on the voltage value and phase of one line voltage (V _RS , V _ST , V _TR ) and one phase voltage (V _R , V _S , V _T ) of the three-phase AC circuit. The directional protection relay device according to claim 2, wherein an accident aspect of a short circuit accident of the three-phase AC circuit is determined. The accident mode judging means is configured to _detect a voltage value and a phase of one line voltage (V _RS , V _ST , V _TR ) of the three-phase AC circuit and a short-circuit current (I _Ry) input from the two-phase through current transformer. The direction protection relay device according to claim 2, wherein an accident aspect of a short-circuit accident of the three-phase AC circuit is determined based on the phase of the three-phase AC circuit. The first phase voltage (V _R ) of the three-phase AC circuit is in the polarity direction, and the second phase voltage (V _S ) of the three-phase AC circuit is in the opposite polarity direction. The first to second circuits are used for determining the accident aspect of the short-circuit accident of the three-phase AC circuit in which the secondary side is connected so as to synthesize the phase voltage (V _T ) by doubling in the opposite polarity direction. An accident mode judging transformer (110) for obtaining a composite voltage (V _RS-2T ) of the phase voltages of the three phases;
The accident aspect determination means is based on the voltage value and phase of the combined voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the two-phase through current transformer. Determine the accident aspect of the short circuit accident of the three-phase AC circuit,
The direction protection relay device according to claim 2, wherein The first phase voltage (V _R ) of the three-phase AC circuit is in the polarity direction, and the second phase voltage (V _S ) of the three-phase AC circuit is in the opposite polarity direction. The first to third are used for determining the accident aspect of the short-circuit accident of the three-phase AC circuit in which the secondary side is connected so that the phase voltage (V _T ) is doubled and synthesized in the polarity direction. A fault condition judging transformer (120) for obtaining a composite voltage (V _{R-S + 2T} ) of the phase voltages of the phases;
The accident aspect determination means is based on the voltage value and phase of the combined voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the two-phase through current transformer. Determine the accident aspect of the short circuit accident of the three-phase AC circuit,
The direction protection relay device according to claim 2, wherein The first phase voltage (V _R ) of the three-phase AC circuit is multiplied by a in the polarity direction or the antipolar direction, and the second phase voltage (V _S ) of the three-phase AC circuit is changed in the polarity direction or antipolar direction. And the secondary side is connected so that the third phase voltage (V _T ) of the three-phase AC circuit is multiplied by c in the polarity direction or the opposite polarity direction to be combined, and the three-phase AC A _fault condition judging transformer for obtaining a composite voltage (V _{aR + bS + cT} ) of the phase voltages of the first to third phases used for judging the accident situation of the short circuit accident of the circuit;
The accident aspect determination means is based on the voltage value and phase of the combined voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the two-phase through current transformer. Determine the accident aspect of the short circuit accident of the three-phase AC circuit,
The direction protection relay device according to claim 2, wherein The two-phase through current transformer (10) is installed in a transmission and distribution line;
The first and second phases of the transmission and distribution lines are penetrated through the annular core of the two-phase through-current transformer different times in the same direction,
When the direction protection relay detects a short-circuit fault based on the short-circuit current (I _Ry ) input from the two-phase through current transformer and the voltage information of the transmission / distribution line, it is installed in each phase of the transmission / distribution line A short-circuit direction relay (4) that collectively shuts off the _first to _third circuit breakers (2 ₁ to 2 ₃ ).
The direction protection relay device according to any one of claims 1 to 8, characterized in that. The two-phase through current transformer (10) is installed in a transmission and distribution line;
The first and second phases of the transmission and distribution lines are penetrated through the annular core of the two-phase through-current transformer different times in the same direction,
When the direction protection relay detects a short-circuit fault based on the short-circuit current (I _Ry ) input from the two-phase through current transformer and the voltage information of the transmission / distribution line, it is installed in each phase of the transmission / distribution line A distance relay (20) that collectively cuts off the _first to _third circuit breakers (2 ₁ to 2 ₃ ),
The direction protection relay device according to any one of claims 1 to 8, characterized in that. The distance relay is a short circuit input from the correction voltage (V _Ry ) obtained from the combined voltage input from the fault condition determination transformer according to claim 6 and the two-phase through current transformer. 11. The directional protection relay device according to claim 10, wherein a short-circuit accident of the three-phase AC circuit is detected based on a current (I _Ry ). The two-phase through current transformers are first and second two-phase through current transformers (10 ₁ , 10 ₂ ) installed in the first and second transmission and distribution lines (1L, 2L), respectively.
The first phase and the second phase of the first transmission / distribution line are passed through the annular core of the first two-phase through-current transformer different times in the same direction;
The first phase and the second phase of the second power transmission and distribution line are penetrated through the annular iron core of the second two-phase through-current transformer differently in the same direction,
The directional protection relay is a short-circuit current (I _Ry ) that is a difference between a short-circuit current input from the first two-phase through current transformer and a short-circuit current input from the second two-phase through current transformer. And a voltage information of the transmission / distribution line, the first to third lines installed in the respective phases of the first transmission / distribution line are detected. When the circuit breakers (2 _{1 to} 2 ₃ ) are collectively cut off and it is detected that a short-circuit accident has occurred in the second transmission / distribution line based on the short-circuit current and the voltage information of the transmission / distribution line, the second A line selection relay (30) that collectively shuts off the _fourth to _sixth circuit breakers (2 ₄ to 2 ₆ ) installed in each phase of the transmission and distribution line of
The direction protection relay device according to any one of claims 1 to 8, characterized in that. A power direction relay device for protecting a three-phase AC circuit from reverse power flow,
A two-phase through current transformer (10) in which an arbitrary two phases of the three-phase AC circuit are penetrated in the same direction by a different number of times through an annular iron core wound with a secondary coil;
When a reverse power flow is detected based on the current (i _Ry ) input from the two-phase through current transformer and the reference voltage obtained from the voltage information of the three-phase AC circuit input from the instrument transformer (6) A power direction relay (40) that collectively cuts off the _first to _third circuit breakers (2 ₁ to 2 ₃ ) installed in each phase of the three-phase AC circuit;
A power direction relay device comprising: The power direction relay multiplies the current input from the two-phase through current transformer by a predetermined multiple to calculate a correction current (i _Ry '), and reverses based on the calculated correction current and the reference voltage. 14. The power direction relay device according to claim 13, wherein when the power flow is detected, the first to third circuit breakers are collectively cut off.   The power direction relay uses a voltage obtained by advancing the phase of the reference voltage by 90 ° as another reference voltage, or a current input from the two-phase through current transformer or a correction current calculated by multiplying the current by a predetermined multiple The power direction relay device according to claim 13 or 14, wherein the power direction relay device functions as a reactive power direction relay by detecting a reverse power flow based on the reference voltage and the other reference voltage.