JP2010166782A - 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 fault or an inverse flow, and 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 an annular iron core of a three-phase through current transformer 10 installed on a power transmission line so as to be mutually inverse only one time, while the T-phase of the power transmission line is led through in the same direction as the R-phase two times. Upon detecting a short-circuit fault based on a short-circuit current I<SB>Ry</SB>inputted from the three-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. 17, 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. 18, 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 to the second and third phase relays 20 3. The S-phase and T-phase short-circuit currents are input from the current transformers 3 ₂ and 3 ₃ , respectively, 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. 19, 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 transmission lines 1L, 2L is inputted from the _fifth current transformers 3 ₂ , 3 ₅ and the S-phase phase voltage V _S is inputted 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. 20, _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 the broken arrows in FIG. )), Effective currents i _RP , i _SP and 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. 21, the _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.
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. 21), 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. 21), the _first to _third circuit breakers 2 ₁ to 2 ₃ are collectively cut off.

Note that, in the _first to _third power direction relays 40 ₁ to 40 ₃ shown in FIG. 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 a second core of the three-phase AC circuit is mounted on an annular core wound with a secondary coil. A three-phase through current transformer in which a phase is passed through the same or different number of times in the opposite direction to the first phase and a third phase of the three-phase AC circuit is passed through the same number of times in the same direction as the first phase. And detecting a short-circuit accident based on the short-circuit current input from the three-phase through current transformer and the voltage information of the three-phase AC circuit, the first to third phases of the three-phase AC circuit are respectively detected. It is characterized by comprising a direction protection relay that collectively shuts off the installed circuit breakers.
The direction protection relay further includes 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 three-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 circuit breakers installed in the first to third phases may be 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. 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 determining means is configured to _detect a voltage value and 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 three-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 determination transformer (110) for obtaining a composite voltage (V _RS-2T ) of the phase voltages of the three phases, wherein the accident mode determination means is input from the accident mode determination 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 three-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 combined voltage and the phase of the short-circuit current (I _Ry ) input from the three-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 composite voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the three-phase through current transformer. You may determine the accident aspect of the short circuit accident of the said three-phase alternating current circuit.
The three-phase through current transformer (10) is installed in a transmission / distribution line, and the second phase of the transmission / distribution line is the same as the first phase in the opposite direction to the annular core of the three-phase through current transformer. And the third phase of the transmission / distribution line is penetrated a different number of times in the same direction as the first phase, and the direction protection relay is input from the three-phase through current transformer When a short-circuit accident is detected based on the short-circuit current (I _Ry ) and the voltage information of the transmission / distribution line, the first to third interruptions respectively installed in the first to third phases of the transmission / distribution line The short circuit direction relay (4) which cuts off the devices (2 _{1 to} 2 ₃ ) collectively may be used.
The three-phase through current transformer (10) is installed in a transmission / distribution line, and the second phase of the transmission / distribution line is the same as the first phase in the opposite direction to the annular core of the three-phase through current transformer. And the third phase of the transmission / distribution line is penetrated a different number of times in the same direction as the first phase, and the direction protection relay is input from the three-phase through current transformer When a short-circuit accident is detected based on the short-circuit current (I _Ry ) and the voltage information of the transmission / distribution line, the first to third interruptions respectively installed in the first to third phases of the transmission / distribution line It may be a distance relay (20) that collectively shuts off the devices (2 _{1 to} 2 ₃ ).
The distance relay is a short circuit input from the correction voltage (V _Ry ) obtained from the composite voltage input from the fault condition determination transformer according to any one of claims 6 to 8 and the three-phase through current transformer. A short circuit accident of the three-phase AC circuit may be detected based on the current (I _Ry ).
The three-phase through current transformers are first and second three-phase through current transformers (10 ₁ , 10 ₂ ) installed in the first and second transmission and distribution lines (1L, 2L), respectively. The second phase of the first transmission / distribution line is passed through the annular core of the first three-phase through current transformer the same number of times in the opposite direction to the first phase, and the first transmission / distribution line The third phase of the second phase of the second power transmission and distribution line is inserted through the annular core of the second three-phase through current transformer in a different number of times in the same direction as the first phase. Is penetrated the same number of times in the opposite direction to the first phase and the third phase of the second transmission and distribution line is penetrated a different number of times in the same direction as the first phase, A short-circuit current input from the first three-phase through current transformer and a short-circuit current input from the second three-phase through current transformer in the direction protection relay When short circuit to the first transmission and distribution lines on the basis of the short-circuit current which is the difference current between (I _Ry) and voltage information of the transmission and distribution lines to detection of occurrence, the first of the first transmission and distribution lines The first to third circuit breakers (2 ₁ to 2 ₃ ) respectively installed in the first to third phases are collectively cut off, and the second circuit is based on the short circuit current and the voltage information of the transmission and distribution lines. When it is detected that a short-circuit accident has occurred in the transmission / distribution line, _fourth to _sixth circuit breakers (2 ₄ to 2 ₆ ) installed in the first to third phases of the second transmission / distribution line, respectively. It may be a line selection relay (30) that cuts off all of them.
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 a second core of the three-phase AC circuit is mounted on an annular core wound with a secondary coil. A three-phase through current transformer in which a phase is passed through the same or different number of times in the opposite direction to the first phase and a third phase of the three-phase AC circuit is passed through the same number of times in the same direction as the first phase. (10) and the reference voltage obtained from the current (i _Ry ) input from the three-phase through current transformer and the voltage information of the three-phase AC circuit input from the instrument transformer (6). When a reverse power flow is detected, a power direction relay (40) that collectively shuts off the _first to _third circuit breakers (2 ₁ to 2 ₃ ) installed in the first to third phases of the three-phase AC circuit, respectively. It is characterized by comprising.
Here, the power direction relay multiplies the current input from the three-phase through current transformer by a predetermined multiple to calculate a correction current (i _Ry '), and calculates the correction current and the reference voltage. If a reverse power flow is detected based on this, the first to third circuit breakers may be 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 three-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 three-phase through current transformers, the number of 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 three-phase feed-through current transformer varies 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 amplitude of the short-circuit current 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.

  To achieve the above object, the second phase of the three-phase AC circuit is passed through the annular core around which the secondary coil is wound in the same direction or different times in the opposite direction to the first phase, and the third phase of the three-phase AC circuit. Using a three-phase through current transformer that penetrates the same direction as the first phase a different number of times, the direction protection relay is connected between the short-circuit current input from the three-phase through current transformer and the line of the three-phase AC circuit. When a short-circuit accident is detected based on the voltage, the circuit breakers installed in the first to third phases of the three-phase AC circuit are collectively disconnected, and the power direction relay is input from the three-phase through current transformer When a reverse power flow is detected on the basis of the detected current and the reference voltage obtained from the voltage information of the three-phase AC circuit input from the instrument transformer, it is installed in each of the first to third phases of the three-phase AC circuit. This was realized by shutting off all the circuit breakers.

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 three-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 three-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 A short-circuit direction relay 4 that collectively shuts off the _first to _third circuit breakers 2 ₁ to 2 ₃ installed in the R phase, the S phase, and the T phase, respectively.

Here, the three-phase through current transformer 10 allows the S phase of the transmission / distribution line to pass through the annular core around which the secondary coil is wound, the same number of times in the opposite direction to the R phase, and the T phase of the transmission / distribution line to be the R phase. Is a through-type current transformer that is penetrated in the same direction by different numbers of times. That is, both the R phase and the T phase of the power transmission and distribution line are penetrated in the polarity direction of the three-phase through current transformer 10 (direction from the first opening surface of the annular core to the second opening surface of the annular core). However, the S phase of the power transmission / distribution line is penetrated in the antipolar direction of the three-phase through current transformer 10 (the direction from the second opening surface of the annular core to the first opening surface of the annular core).
Moreover, although the R phase and S phase of the transmission / distribution line are penetrated through the three-phase through current transformer 10 only once, the T phase of the transmission / distribution line is penetrated through the three-phase through current transformer 10 twice. Yes. As a result, the sum current of the current flowing through the R phase and the current flowing through the S phase of the transmission / distribution line and the current obtained by inverting the current flowing through the T phase is doubled from the three-phase through current transformer 10. Is output.

Therefore, when the load currents flowing in the R phase, S phase, and T phase of the transmission and distribution line when no short circuit accident has occurred are represented by I _R , I _S , and I _T , as shown in FIG. phase through the load current I from the current transformer 10 is input to the short-circuit direction relay 4 twice the load current I _T of the load current -I _S and T phases of the load R-phase current I _R and polarity negative S phase the current (= 2I _T) and becomes the vector sum of the phase of the load current I _T of the load current I _S and T phases of the load current I _R and S phases of the R phase is shifted by 120 ° intervals The amplitude of the load current I is 7 ^1/2 times the amplitude of the R-phase load current I _R (S-phase and T-phase load currents I _S and I _T ).
I = I _R −I _S + 2I _T
| I | = | I _R −I _S + 2I _T | = {(3 ^1/2 ) ² +2 ² } ^1/2 × | I _R |
= 7 ^1/2 × | I _R | (= 7 ^1/2 × | I _S | = 7 ^1/2 ×
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 1/7 ^1/2 .
I ′ = I × ^{1/7 1/2}
| I ′ | = | I | × 1/7 1/ ^2- = | I _R | (= | I _S | = | I _T |)

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 three-phase through current transformer 10 to the short-circuit direction relay 4 is a vector sum of the R-phase short-circuit current I _FR and the negative-polarity S-phase short-circuit current −I _FS. 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 R-phase short-circuit current I _FR as shown in FIG. It becomes twice the amplitude of (S phase short circuit current I _FS ).
I _Ry = I _FR −I _FS
| I _Ry | = | I _FR −I _FS | = 2 × | I _FR | (= 2 × | I _FS |)
In FIGS. 3 and 4, short-circuit currents I _FR , I _FS , I _FT flowing in the inner direction of the transmission / distribution line are solid arrows, and short-circuit currents I _FR , I _FS , I _FT is indicated by a dashed-dotted 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 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 _FR | (= | 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 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 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 .
(2) S-phase -T For short circuit between the phases when the short circuit of the S-phase -T phase occurs, as indicated by broken line arrow in FIG. 5, the short-circuit current of the S-phase to the S phase of the transmission and distribution lines I _FS There flow inside direction, but the short-circuit current I _FT T-phase to the T phase of the transmission and distribution lines to flow to the outside direction, the R-phase of the 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 three-phase through current transformer 10 to the short-circuit direction relay 4 is a current obtained by doubling the S-phase short-circuit current −I _FS and the T-phase short-circuit current I _FT having a negative polarity (= 2I _FT ), but since the phase difference between the S-phase short-circuit current I _FS and the T-phase short-circuit current I _FT is 180 °, the amplitude of the short-circuit current I _Ry is shown in FIG. As shown, it is three times the amplitude of the T-phase short-circuit current I _FT (S-phase short-circuit current I _FS ).
I _Ry = −I _FS + 2I _FT
| I _Ry | = | −I _FS + 2I _FT | = 3 × | I _FT | (= 3 × | 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 corrected short-circuit current I _Ry ′ is calculated by multiplying the short-circuit current I _Ry by 1/3.
I _Ry '= I _Ry × 1/3
| I _Ry '| = | I _Ry | × 1/3 = | I _FT | (= | 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), the calculated correction circuit current I _Ry 'and S phase -T phase of the line voltage V _ST ( 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 .
(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. 6, 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.
Therefore, the short-circuit current I _Ry output from the three-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 T-phase short-circuit current I _FT (= 2I _FT ). Although it is a vector sum, since the phase difference between the R-phase short-circuit current I _FR and the T-phase short-circuit current I _FT is 180 °, the amplitude of the short-circuit current I _Ry is T-phase as shown in FIG. The amplitude of the short-circuit current I _FT (R-phase short-circuit current I _FR ).
I _Ry = I _FR + 2I _FT
| I _Ry | = | I _FR + 2I _FT | = | I _FT | (= | 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 _FT | (= | 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 between the T phase and the R phase The magnitude and direction of the short-circuit current I _Ry is determined based on the above.
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 case of short-circuit accident between R-phase, S-phase, and T-phase When a short-circuit accident occurs between R-phase, S-phase, and T-phase, as indicated 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 three-phase through current transformer 10 to the short-circuit direction relay 4 is the R-phase short-circuit current I _FR , the negative polarity S-phase short-circuit current −I _FS, and the T-phase short-circuit current I _Although it is a vector sum with the current doubled by _FT (= 2I _FT ), 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 are out of phase by 120 °. Therefore, the amplitude of the short-circuit current I _Ry is 7 ^1/2 times the amplitude of the R-phase short-circuit current I _FR (S-phase and T-phase short-circuit currents I _FS and I _FT ) as shown in FIG. It becomes.
I _Ry = I _FR -I _FS + 2I _FT
| I _Ry | = | I _FR −I _FS + 2I _FT | = {(3 ^1/2 ) ² +2 ² } ^1/2 × | I _R |
= 7 ^1/2 × | I _FR | (= 7 ^1/2 × | I _FS | = 7 ^1/2 × | I _FT |)
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 1/7 ^1/2 .
I _Ry '= I _Ry × _1/7 ^1/2
_{| I Ry '| = | I} Ry | × 1/7 1/2 - = | I FR | (= | I FS | = | I FT |)
Further, since the short-circuit current I _Ry is input from the three-phase through current transformer 10 to the short-circuit direction relay 4 with a leading phase of 49.1 °, 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 / distribution line, as shown in FIG. 4B, the corrected short circuit current I _Ry 'corrected for the phase and the line between the R phase and the S phase The magnitude and direction of the short circuit current I _Ry is determined based on the voltage V _RS .
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 three-phase through current transformer 10 has the S phase of the transmission / distribution line penetrated the same number of times in the opposite direction to the R phase and the T phase of the transmission / distribution line has been penetrated a different number of times in the same direction as the R phase. The T phase of the transmission / distribution line may be penetrated the same number of times in the opposite direction to the S phase, and the R phase of the transmission / distribution line may be penetrated the same number of times in the same direction as the S phase. The S phase of the power transmission / distribution line may be penetrated the same number of times in the same direction as the T phase while being penetrated the same number of times in the opposite direction to the T phase.

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”) penetrating the three-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 a phase that penetrates in the polarity direction of the three-phase through current transformer, and “−” in the CT connection indicates the opposite polarity direction in the three-phase through current transformer. The phase penetrated by is shown.

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 three-phase through current transformer 10, but the load current the amplitude of I is 7 ^1/2, twice the amplitude of the short-circuit current I _Ry amplitude of the short-circuit current I _Ry in short circuit of the R-phase -S phase is in a short circuit accident T phase -R phase, The amplitude of the short-circuit current I _Ry in the short-circuit accident between the S phase and the T phase is three times the amplitude of the short-circuit current I _Ry in the short-circuit accident between the T phase and the R phase, and the short circuit accident between the R phase, the S phase, and the T phase. short-circuit current the amplitude of the I _Ry is ^71/2 times the amplitude of the short-circuit current I _Ry in short circuit of the T-phase -R phases in the detection sensitivity and operating time of the short-circuit direction relay for all accidents aspects in order to be the same, the response of the short-circuit current I _Ry to the accident aspects It is necessary to correct Te.

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 three-phase through current transformer 10. The short-circuit current I _Ry is corrected by multiplying by 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. 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 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. 8C).
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 ° (ie, 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 the phase is not larger (that is, larger than −6.76 ° and smaller than 6.76 °) (FIG. 8D). 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 three-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 respect to the phase = 210 ° as a reference, it is determined that there is a short circuit accident between the R phase and the S phase (FIG. 9 ( 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 a short circuit accident between the S phase and the T phase occurs (FIG. 9). (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 (30 ° ≦ γ ≦ 90 °, γ is an impedance angle θ = 75 °). ), It is determined that there is a short circuit accident between the T phase and the R phase (see FIG. 9C).
(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 ° (ie, greater than −5.95 ° and 5 Less than .95 °) and the phase of the short-circuit current I _Ry is within a predetermined second angle range δ (100.9 ° ≦ δ ≦ 169.1 °, where δ is an impedance angle θ = 75 °, arc resistance, etc. 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. 9D).

(Fourth accident mode determination method)
The accident aspect determination transformer 110 (according to the first embodiment of the present invention) shown in FIG. 10 is installed on the bus, and the composite voltage V _RS− output from the accident aspect determination transformer 110 is installed. _{Based on} the voltage value and phase of _2T and the phase of the short-circuit current I _Ry , the accident aspect is determined 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)). Further, the phase of the composite voltage V _RS-2T at the time of the short circuit accident is determined to be a predetermined first composite voltage angle range ε ₁ (7 based on the phase of the composite voltage V _RS-2T at the normal time being 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 within a predetermined first short-circuit current angle range λ ₁ (−19.1 ° ≦ λ ₁ ≦ 40.9 °), it is determined that a short-circuit accident between the R phase and the S phase occurs.
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 / 110.05)
= 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 advanced only within a predetermined second short-circuit current angle range λ ₂ (19.1 ° ≦ λ ₂ ≦ 79.1 °) (−λ ₂ ), between the S phase and the 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 advances only within a predetermined third short-circuit current angle range λ ₃ (79.1 ° ≦ λ ₃ ≦ 139.1 °) (−λ ₃ ), 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. When it is advanced (−λ ₄ ) only within the fourth short-circuit current angle range λ ₄ (8.2 ° ≦ λ ₄ ≦ 68.2 °), it is determined as a short-circuit accident between the R phase, the S phase, and the T phase. .

(Fifth accident mode determination method)
Accident aspects determination transformer 120 shown in FIG. 11 (accident appearance determination transformer according to a second embodiment of the present invention) is placed to the bus, composite voltage output from the accident aspect determination transformer 120 V _{R- Based on} the voltage value and phase of _{S + 2T} and the phase of the short-circuit current I _Ry , 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 delayed (+ λ ₅ ) by a predetermined fifth short-circuit current angle range λ ₅ (79.1 ° ≦ λ ₅ ≦ 139.1 °) It is determined as 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 delayed by (+ λ ₆ ) within the predetermined sixth short-circuit current angle range λ ₆ (19.1 ° ≦ λ ₆ ≦ 79.1 °) It is determined as a short-circuit accident between phase T and phase T.
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 when the phase of the short-circuit current I _Ry is within a predetermined seventh short-circuit current angle range λ ₇ (−40.9 ° ≦ λ ₇ ≦ 19.1 °) Judged as a short circuit accident.
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 is delayed (+ λ ₈ ) by a predetermined eighth short-circuit current angle range λ ₈ (30 ° ≦ λ ₈ ≦ 90 °), it is determined as a short-circuit accident between the R phase, the S phase, and the T phase. To do.

Next, a directional protection relay device according to a second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 12, the direction protection relay device according to the present embodiment includes a three-phase through current transformer 10 installed in a transmission / distribution line, an instrument transformer 6 installed in a bus, and a three-phase through transformer. R-phase-S-phase line obtained from short-circuit current I _Ry input from current collector 10 and R-phase, S-phase, and T-phase phase voltages V _R , V _S , V _T 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 three-phase through current transformer 10 allows the S phase of the transmission / distribution line to pass through the annular core around which the secondary coil is wound, the same number of times in the opposite direction to the R phase, and the T phase of the transmission / distribution line to be the R phase. Is a through-type current transformer that is penetrated in the same direction by different numbers of times. That is, the R phase and the T phase of the transmission / distribution line are both penetrated in the polarity direction of the three-phase through current transformer 10, but the S phase of the transmission / distribution line is directed in the opposite polarity direction of the three-phase through current transformer 10. Is penetrated.
Moreover, although the R phase and S phase of the transmission / distribution line are penetrated through the three-phase through current transformer 10 only once, the T phase of the transmission / distribution line is penetrated through the three-phase through current transformer 10 twice. Yes. As a result, the sum current of the current flowing through the R phase and the current flowing through the S phase of the transmission / distribution line and the current obtained by inverting the current flowing through the T phase is doubled from the three-phase through current transformer 10. Is output.

Therefore, when the load currents flowing in the R-phase, S-phase, and T-phase of the transmission and distribution line when no short-circuit accident has occurred are represented by I _R , I _S , and I _T , the distance relay from the three-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 20 is the R-phase load current I _R and the negative-polarity S-phase load current −I _S It becomes a vector sum with a current (= 2I _T ) that is twice the T-phase load current I _T , and the amplitude of the load current I is R-phase load current I _R (S-phase and T-phase load currents I _S , I _T ) Is 7 ^1/2 times the amplitude of.
I = I _R −I _S + 2I _T
| I | = | I _R −I _S + 2I _T | = {(3 ^1/2 ) ² +2 ² } ^1/2 × | I _R |
= 7 ^1/2 × | I _R | (= 7 ^1/2 × | I _S | = 7 ^1/2 × | I _T |)
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. 18, the load current as shown by the following formula The corrected load current I ′ is calculated by multiplying I by 3 ^1/2 / 7 ^1/2 .
I ′ = I × 3 ^1/2 / 7 ^1/2
| I ′ | = | I | × 3 ^1/2 / 7 ^1/2 − = 3 ^1/2 × | I _R | (= 3 ^1/2 × | I _S | = 3 ^1/2 × | I _T | )

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. 12, the short-circuit current of the R-phase to R-phase of transmission and distribution lines I _FR 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.
Therefore, the short-circuit current I _Ry input from the three-phase through current transformer 10 to the distance relay 20 is the same as the short-circuit current relay 4 in the first embodiment described above and the R-phase short-circuit current I _FR . The vector sum of the negative polarity S-phase short-circuit current −I _FS and the amplitude of the short-circuit current I _Ry is twice the amplitude of the R-phase short-circuit current I _FR (S-phase short-circuit current I _FS ). 3 (a)).
I _Ry = I _FR −I _FS
| I _Ry | = | I _FR −I _FS | = 2 × | I _FR | (= 2 × | I _FS |)
Therefore, distance relay 20, to the same as the amplitude of the short circuit current inputted to the first to third distance relay 20 ₁ to 20 ₃ of the prior art shown in Figure 18, 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 _FR | (= 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 R phase and the S 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 _RS between the R phase and the S phase. The direction of I _Ry is determined (see FIG. 3A).
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.
(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 While the short-circuit current I _FT T-phase to phase flows to the outside direction, the R-phase of the transmission and distribution lines does not flow a short-circuit current I _FR of R-phase (see FIG. 5).
Accordingly, the short-circuit current I _Ry input from the three-phase through current transformer 10 to the distance relay 20 is short-circuited in the S phase having a negative polarity in the same manner as the short-circuit direction relay 4 in the first embodiment described above. The vector sum of the current −I _FS and the current (= 2I _FT ) twice the T-phase short-circuit current I _FT , and the amplitude of the short-circuit current I _Ry is the T-phase short-circuit current I _FT (S-phase short-circuit current I _FS ) Is three times the amplitude (see FIG. 3B).
I _Ry = −I _FS + 2I _FT
| I _Ry | = | −I _FS + 2I _FT | = 3 × | I _FT | (= 3 × | 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. 18, the short-circuit current as shown by the following formula The corrected short circuit current I _Ry ′ is calculated by multiplying I _Ry by 2/3.
I _Ry '= I _Ry × 2/3
| I _Ry '| = | I _Ry | × 2/3 = 2 × | I _FT | (= 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 / distribution line, the accident point is based on the calculated corrected short circuit current I _Ry ′ and the line voltage V _ST (negative polarity) between the S phase and the T phase. And the direction of the short-circuit current I _Ry are determined (see FIG. 3B).
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.
(3) When T phase -R phase short fault when T-phase -R phase short-circuit accident occurs, the short-circuit current I _FT T-phase to the T phase of the transmission and distribution lines to flow inside direction, the transmission and distribution lines R 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. 6).
Therefore, short-circuit current I _Ry inputted from the three-phase through current transformer 10 to the distance relay 20, as in the case of the short-circuit direction relay 4 in the first embodiment described above, the short-circuit current I _FR of R-phase It becomes a vector sum with a current (= 2I _FT ) that is twice the T-phase short-circuit current I _FT, and the amplitude of the short-circuit current I _Ry becomes the amplitude of the T-phase short-circuit current I _FT (R-phase short-circuit current I _FR ). (See FIG. 4 (a)).
I _Ry = I _FR + 2I _FT
| I _Ry | = | I _FR + 2I _FT | = | I _FT | (= | 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. 18, 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 _FT | (= 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 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 _TR between the T phase and the R phase. The direction of I _Ry is determined (see FIG. 4A).
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.
(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. 7).
Therefore, the short-circuit current I _Ry input from the three-phase through current transformer 10 to the distance relay 20 is the same as the short-circuit current relay 4 in the first embodiment described above and the R-phase short-circuit current I _FR . The negative polarity S-phase short-circuit current -I _FS and the T-phase short-circuit current I _FT are multiplied by the vector (= 2I _FT ), and the amplitude of the short-circuit current I _Ry is the R-phase short-circuit current I _FR (S phase and T phase short circuit currents I _FS , I _FT ) is 7 ^1/2 times the amplitude (see FIG. 4B).
I _Ry = I _FR -I _FS + 2I _FT
| I _Ry | = | I _FR −I _FS + 2I _FT | = {(3 ^1/2 ) ² +2 ² } ^1/2 × | I _FR |
= 7 ^1/2 × | I _FR | (= 7 ^1/2 × | I _FS | = 7 ^1/2 × | I _FT |)
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. 18, the short-circuit current as shown by the following formula I _Ry is multiplied by 3 ^1/2 / 7 ^1/2 to calculate a corrected short-circuit current I _Ry '.
I _Ry '= I _Ry × 3 ^1/2 / 7 ^1/2
_{| I Ry '| = | I} Ry | × 3 1/2 / 7 1/2 - = 3 1/2 × | I FR | (= 3 1/2 × | I FS | = 3 1/2 × | I _FT |)
Further, since the short circuit current I _Ry is input from the three-phase through current transformer 10 to the distance relay 20 with a leading phase of 49.1 °, 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 / distribution line, the fault point is determined based on the corrected short circuit current I _Ry ′ corrected for the phase and the line voltage V _RS between the R phase and the S phase. The distance and the direction of the short-circuit current I _Ry are determined (see FIG. 4B).
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 the case of a short circuit accident between R phase, S phase and T phase R-phase and S-phase line voltage obtained from R-phase and S-phase phase voltages V _R and V _S input from instrument transformer 6 Let V _RS be the correction voltage V _Ry .
V _Ry = V _RS

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 the case of a short-circuit accident between the R phase and the S phase V _Ry = 110 × (V _RS-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 _RS-2T −103.94) /6.06
(3) In the case of a short circuit accident between the T phase and the R phase V _Ry = 110 × (V _RS-2T -20.79) /89.21
(4) In case of short circuit between R phase, S phase and T phase V _Ry = V _RS-2T

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 three-phase through current transformer 10 has the S phase of the transmission / distribution line penetrated the same number of times in the opposite direction to the R phase and the T phase of the transmission / distribution line has been penetrated a different number of times in the same direction as the R phase. The T phase of the transmission / distribution line may be penetrated the same number of times in the opposite direction to the S phase, and the R phase of the transmission / distribution line may be penetrated the same number of times in the same direction as the S phase. The S phase of the power transmission / distribution line may be penetrated the same number of times in the same direction as the T phase while being penetrated the same number of times in the opposite direction to the T phase.

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. 13, the first three-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 three-phase through current transformers 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 three-phase through current transformer vessel 10 ₁ short-circuit current is input and from the second three-phase through the difference in short-circuit current input from the current transformer 10 ₂ current (hereinafter, "short-circuit current I _Ry" as referred.) and a potential 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 three-phase through current transformer 10 _1, the annular core formed by winding a secondary coil of S-phase of the first transmission and distribution lines 1L with pass through the same number of times in the R-phase and opposite second This is a through-type current transformer in which the T phase of one transmission / distribution line 1L is penetrated a different number of times in the same direction as the R phase. Ie, R-phase and T-phase of the first transmission and distribution lines 1L are both through the first three-phase through current transformer 10 _first polarity direction but, S-phase of the first transmission and distribution lines 1L Part It extends through one of the three-phase through opposite polarity direction of the current transformer 10 _1.
In addition, R-phase and S-phase of the first transmission and distribution lines 1L is through only the first three-phase through current transformer 10 ₁ once but, T-phase of the first transmission and distribution lines 1L twice as it has been through the first three-phase through current transformer 10 _1. Thus, from the first three-phase through current transformer 10 _1, the current flowing through inverted ones and T phases of the polarity of the current flowing through the current and the S phase through the R-phase of the first transmission and distribution lines 1L 2 A sum current with the multiplied current is output.
Similarly, the second three-phase through current transformers 10 _2, the annular core formed by winding a secondary coil of S-phase of the second transmission and distribution lines 2L with pass through the same number of times in the R-phase and opposite second This is a through-type current transformer in which the T phase of the second power transmission / distribution line 2L is passed through the same direction as the R phase a different number of times. Ie, R-phase and T-phase of the second transmission and distribution lines 2L are both through the second three-phase through current transformer 10 _second polarity direction but, S-phase of the second transmission and distribution lines 2L Part The two three-phase through current transformers 10 ₂ are penetrated in the opposite polarity direction.
In addition, R-phase and S-phase of the second transmission and distribution lines 2L is through only the second three-phase through current transformers 10 ₂ once, but, T-phase of the second transmission and distribution lines 2L twice as it has been through the second three-phase through current transformer 10 _2. As a result, the second three-phase through current transformer 10 ₂ has a current flowing through the R phase and a current flowing through the S phase of the second transmission / distribution line 2L, and a current flowing through the T phase as 2 A sum current with the multiplied current is output.
The second three-phase through current transformer 10 ₂ has a short-circuit current polarity input to the line selection relay 30 from the second three-phase through current transformer 10 _{2 in} the first three-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.

Accordingly, 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 input from the first three-phase through current transformer 10 ₁ to the line selection relay 30 In the same manner as in the case of the short-circuit direction relay 4 in the first embodiment, the R-phase load current I _R1 , the negative polarity S-phase load current −I _S1 and the T-phase load current I _T1 are obtained. It becomes a vector sum with the doubled current (= 2I _T1 ), and the amplitude of the load current I is 7 ^1/2 of the amplitude of the R-phase load current I _R1 (S-phase and T-phase load currents I _S1 , I _T1 ). Doubled.
i ₁ = I _R1 −I _S1 + 2I _T1
| I ₁ | = | I _R1 −I _S1 + 2I _T1 | = 7 ^1/2 × | I _R1 | (= 7 ^1/2 × | I _S1 | = 7 ^1/2 × | I _T1 |)
Similarly, the load current i ₂ input from the second three-phase through current transformer 10 ₂ to the line selection relay 30 is the R-phase load current I _R2 and the negative-polarity S-phase load current −I _S2 and T It becomes a vector sum with a current (= 2I _T2 ) that is twice the phase load current I _T2, and the amplitude of the load current i ₂ is the R-phase load current I _R2 (S-phase and T-phase load currents I _S2 , I _T2 ) Is 7 ^1/2 times the amplitude.
i ₂ = − (I _R2 −I _S2 + 2I _T2 )
| I ₂ | = | I _R2 −I _S2 + 2I _T2 | = 7 ^1/2 × | I _R2 | (= 7 ^1/2 × | I _S2 | = 7 ^1/2 × | I _T2 |)
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 1/7 ^1/2 .
I ′ = I × ^{1/7 1/2}
| I '| = | I | × 1/7 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 indicated 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.
Accordingly, 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 and the short-circuit current flowing in the R-phase of the second transmission and distribution line 2L) and the negative S-phase short-circuit current -I _FS (S of the first transmission and distribution line 1L) Of the difference between the short-circuit current flowing in the phase and the short-circuit current flowing in the S-phase of the second transmission and distribution line 2L), and the amplitude of the short-circuit current I _Ry is the short-circuit current I in the R-phase It becomes twice the amplitude of _FR (S-phase short-circuit current I _FS ) (see FIG. 3A).
I _Ry = I _FR −I _FS
| I _Ry | = | I _FR −I _FS | = 2 × | I _FR | (= 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 _FR | (= | 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 R-phase and S-phase of the first or second transmission and distribution lines 1L, 2L, the calculated corrected short-circuit current I _Ry ′ and the R-phase to S-phase line voltage V _RS Based on this, an 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. 5).
Accordingly, the short-circuit current I _Ry input to the line selection relay 30 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 (first The polarity of the difference current between the short-circuit current flowing in the S phase of the first transmission and distribution line 1L and the short-circuit current flowing in the S phase of the second transmission and distribution line 2L) and the T-phase short-circuit current I _FT (first becomes the vector sum of the transmission and distribution lines 1L of T phase short-circuit current flowing through the differential current) to twice the current of the short-circuit current flowing through the T-phase of the second transmission and distribution lines 2L (= 2I _FT), short-circuit current I _Ry Is three times the amplitude of the T-phase short-circuit current I _FT (S-phase short-circuit current I _FS ) (see FIG. 3B).
I _Ry = −I _FS + 2I _FT
| I _Ry | = | −I _FS + 2I _FT | = 3 × | I _FT | (= 3 × | 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 corrected short-circuit current I _Ry ′ is calculated by multiplying the short-circuit current I _Ry by 1/3.
I _Ry '= I _Ry × 1/3
| I _Ry '| = | I _Ry | × 1/3 = | I _FT | (= | 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 line voltage V _ST (polarity between the S phase and the T phase) Is negative), 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 _IF flows (see FIG. 6).
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). Difference current between the short-circuit current flowing in the R-phase and the short-circuit current flowing in the R-phase of the second transmission and distribution line 2L) and the T-phase short-circuit current I _FT (short-circuit current flowing in the T-phase of the first transmission and distribution line 1L) And the current (= 2I _FT ) that is twice the difference between the short-circuit current flowing in the T-phase of the second transmission / distribution line 2L and the amplitude of the short-circuit current I _Ry is the T-phase short-circuit current I _FT (R phase short-circuit current I _FR ) (see FIG. 4A).
I _Ry = I _FR + 2I _FT
| I _Ry | = | I _FR + 2I _FT | = | I _FT | (= | 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 _FT | (= | 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 the R phase of the first or second transmission and distribution lines 1L and 2L, the calculated corrected short circuit current I _Ry ′ and the line voltage V _TR between the T phase and the R phase are used. Based on this, the accident line is determined (see FIG. 4A).
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. 7).
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 and the short-circuit current flowing in the R-phase of the second transmission and distribution line 2L) and the negative S-phase short-circuit current -I _FS (S of the first transmission and distribution line 1L) The polarity of the difference current between the short-circuit current flowing in the phase and the short-circuit current flowing in the S-phase of the second transmission and distribution line 2L) and the T-phase short-circuit current I _FT (the T-phase of the first transmission and distribution line 1L) the flow circuit current and the differential current) to twice the current of the short-circuit current flowing through the T-phase of the second transmission and distribution lines 2L (= become vector sum of 2I _FT), the amplitude of the short-circuit current I _Ry is the R-phase short-circuit current I _FR (S-phase and T-phase of the short-circuit current I _FS, I _FT) becomes ^71/2 times the amplitude (see FIG. 4 (b) .
I _Ry = I _FR -I _FS + 2I _FT
| I _Ry | = | I _FR −I _FS + 2I _FT | = 7 ^1/2 × | I _FR | (= 7 ^1/2 × | I _FS | = 7 ^1/2 × | I _FT |)
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 1/7 ^1/2 .
I _Ry '= I _Ry × _1/7 ^1/2
_{| I Ry '| = | I} Ry | × 1/7 1/2 - = | I FR | (= | I FS | = | I FT |)
Further, since the short-circuit current I _Ry is input from the three-phase through current transformer 10 to the line selection relay 30 with a leading phase of 49.1 °, 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, S-phase, and T-phase of the first or second transmission / distribution lines 1L, 2L, the phase-corrected short-circuit current I _Ry 'and the R-phase-S-phase line voltage V _RS Based on the above, the accident line is determined (see FIG. 4B).
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 three-phase through current transformer 10 ₁ T-phase of the first transmission and distribution lines 1L with pass through the same number of times the S-phase of the first transmission and distribution lines 1L to R-phase and reverse R The T phase of the first transmission / distribution line 1L is penetrated the same number of times in the opposite direction to the S phase and the R phase of the first transmission / distribution line 1L is defined as the S phase. The same direction may be penetrated a different number of times, or the R phase of the first transmission and distribution line 1L may be penetrated the same number of times in the opposite direction to the T phase and the S phase of the first transmission and distribution line 1L may be defined as the T phase. You may penetrate through the same direction different times.
The same applies to the second three-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. 14, the power direction relay device according to the present embodiment includes a three-phase through current transformer 10 installed in a transmission / distribution line, an instrument transformer 6 installed in a bus, and a three-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 three-phase through current transformer 10 allows the S phase of the transmission / distribution line to pass through the annular core around which the secondary coil is wound, the same number of times in the opposite direction to the R phase, and the T phase of the transmission / distribution line to be the R phase. Is a through-type current transformer that is penetrated in the same direction by different numbers of times. That is, the R phase and the T phase of the transmission and distribution line are both penetrated in the polarity direction of the three-phase through current transformer 10, while the S phase of the transmission and distribution line is penetrated in the opposite polarity direction of the three-phase through current transformer 10. Has been.
Moreover, although the R phase and S phase of the transmission / distribution line are penetrated through the three-phase through current transformer 10 only once, the T phase of the transmission / distribution line is penetrated through the three-phase through current transformer 10 twice. Yes. As a result, the sum current of the current flowing through the R phase and the current flowing through the S phase of the transmission / distribution line and the current obtained by inverting the current flowing through the T phase is doubled from the three-phase through current transformer 10. Is output.

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 flow through the annular core of the three-phase through current transformer 10 in the opposite direction (that is, the R-phase effective current). i _RP flows through the three-phase through current transformer 10 in the polarity direction, and the S-phase effective current i _SP flows through the three-phase through current transformer 10 in the opposite polarity direction), and the R-phase effective current. The i _RP and the T-phase effective current i _TP flow through the annular core of the three-phase through current transformer 10 in the same direction (that is, the R-phase effective current i _RP and the T-phase effective current i _TP are And flows through the three-phase through current transformer 10 in the polar direction).
Therefore, the effective current i _RyP included in the current i _Ry input from the three-phase through current transformer 10 to the power direction relay 40 is _equal to the R-phase effective current i _{RP as} shown by a solid line thick arrow in FIG. The S-phase effective current -i _SP and the T-phase effective current i _TP are multiplied by the vector sum (2i _TP ), but the R-phase effective current i _RP and the S-phase effective current are negative. Since the i _SP and the T-phase effective current i _TP flow through the three-phase through current transformer 10 with a phase difference of 120 ° as shown in FIG. _15A , the amplitude of the effective current i _RyP is R-phase. The effective current i _RP (S phase and T phase effective currents i _SP and i _TP ) is 7 ^1/2 times the amplitude (see FIG. 15A).
i _RyP = i _RP -i _SP +2 i _{TP
| I RyP | = | i RP} -i SP + 2i TP | = 7 1/2 × | i RP | (= 7 1/2 × | i SP | = 7 1/2 × | i TP |)
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 1/7 ^1/2 .
i _Ry '= i _Ry × _1/7 ^1/2
| I _Ry '| = | i _Ry | × _1/7 ^1/2
(| I _RyP '| = | i _RP | (= | i _SP | = | i _TP |))
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 ). Based on (maximum sensitivity angle = 79.1 °), the correction effective current i _RyP ′ included in the correction current i _Ry ′ enters the operation range as indicated by the dashed arrow in FIG. 1 to the third circuit breakers 2 ₁ to 2 ₃ collectively blocking.

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 three-phase through current transformer 10 has the S phase of the transmission / distribution line penetrated the same number of times in the opposite direction to the R phase and the T phase of the transmission / distribution line has been penetrated in the same direction as the R phase by a different number of times. The T phase of the transmission / distribution line may be penetrated the same number of times in the opposite direction to the S phase, and the R phase of the transmission / distribution line may be penetrated the same number of times in the same direction as the S phase. The S phase of the transmission / distribution line may be penetrated the same number of times in the same direction as the T phase while being penetrated the same number of times in the opposite direction to the T phase.
However, the CT connection, power directional relay 40, the reference voltage of the current i _Ry inputted from the three-phase through current transformer 10 1/7 ^1/2 corrected current i _Ry obtained by correcting 'shown in Table 8 And work on the basis of. In Table 8, “+” and “−” of the CT connection indicate the polarity of the current output from the three-phase through current transformer 10 when the direction of the current flowing through each phase of the transmission and distribution line is the + direction. Indicates “+” and “−”.

  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 flow through the annular core of the three-phase through current transformer 10 in the opposite direction (that is, the R-phase reactive current i _SQ i _RQ flows through the three-phase through current transformer 10 in the polarity direction, and the S-phase reactive current i _SQ flows through the three-phase through current transformer 10 in the opposite polarity direction), and the R-phase reactive current. The i _RQ and the T-phase reactive current i _TQ flow through the annular core of the three-phase through current transformer 10 in the same direction (that is, the R-phase reactive current i _RQ and the T-phase reactive current i _TQ are And flows through the three-phase through current transformer 10 in the polar direction).
Therefore, the reactive current i _RyQ included in the current i _Ry input from the three-phase through current transformer 10 to the power direction relay 40 is an R-phase reactive current i _RQ and an S-phase reactive current −i _SQ having a negative polarity. This is the vector sum of the current (2i _TQ ) that is twice the T-phase reactive current i _TQ , but the R-phase reactive current i _RQ , the S-phase reactive current i _SQ, and the T-phase reactive current i _TQ are Since the current flows through the three-phase through current transformer 10 with a phase difference of 120 ° as shown in FIG. 16 (a), the reactive current i _{RyQ has} an amplitude of the reactive current i _RQ of the R phase (effective of the S phase and the T phase). It becomes ^71/2 times the amplitude of the current i _SQ , i _TQ ) (see FIG. 16A).
i _RyQ = i _RQ -i _SQ + 2i _TQ
| I _RyQ | = | i _RQ −i _SQ + 2i _TQ | = 7 ^1/2 × | i _RQ | (= 7 ^1/2 × | i _SQ | = 7 ^1/2 × | i _TQ |)
Therefore, the power direction relay 40 calculates the corrected current i _Ry ′ by multiplying the current i _Ry by 1/7 ^{1/2 as} shown in the following equation.
i _Ry '= i _Ry × _1/7 ^1/2
_{| I Ry '| = | i} Ry | × 1/7 1/2 -
(| I _RyQ '| = | i _RQ | (= | i _SQ | = | i _TQ |))
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 (the negative-polarity S-phase to T-phase line voltage −V _ST ) using the inverted version (−V _ST ) as the reference voltage. (Maximum sensitivity angle = 79.1 °), when the corrected reactive current i _RyQ ′ included in the corrected current i _Ry ′ enters the operating range as indicated by the dashed arrow in FIG. All circuit breakers 2 _{1 to} 2 ₃ are collectively shut off.

The negative polarity S-phase to T-phase line voltage -V _ST was used as the reference voltage, but the polarity of the negative polarity R-phase voltage -V _R may be 90 ° advanced. Good.

  In the above description, the R-phase and S-phases are passed through the three-phase through current transformer once in the opposite direction and the T-phase is passed twice in the same direction. , Let the R phase pass through the three-phase through current transformer l (l ≧ 1) times, let the S phase pass m (m ≧ 1) times in the opposite direction (reverse direction) to the R phase, and make the T phase R phase May be penetrated n (n ≧ 2) times in the same direction (same direction).

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 three-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 three-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 three-phase through current transformer 10 shown in FIG. 1 when a short circuit accident generate | occur | produces. It is a figure for demonstrating short circuit current _IRy input into the short circuit direction relay 4 from the three-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 three-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 three-phase penetration 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. . For explaining the short-circuit current I _Ry input from the three-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. 14 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. 20.

1 Power supply 2 _{1 to} 2 _{6 1st} to _6th circuit breakers 3 _{1 to} 3 _{6 1st} to _6th current transformers 4 Short circuit direction relays 4 ₁ to 4 _{3 1st} to _3rd short circuit direction relays 6 transformer 10 three phase through current transformer 10 _1, 10 ₂ first and second three-phase through current transformer 20 distance relay 20 ₁ to 20 ₃ first to third distance relay 30 lines selected relay 30 ₁ - 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 second phase of the three-phase AC circuit is passed through the annular core around which the secondary coil is wound in the same or different number of times in the opposite direction to the first phase, and the third phase of the three-phase AC circuit is passed through the first phase. A three-phase through current transformer that is penetrated differently in the same direction as one phase;
When a short-circuit fault is detected based on the short-circuit current input from the three-phase through current transformer and the voltage information of the three-phase AC circuit, it is installed in each of the first to third phases of the three-phase AC circuit. A directional protective relay that collectively shuts off
A directional protection relay device comprising:   The direction protection relay further includes 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 three-phase through current transformer includes the fault mode determination unit. When the corrected short circuit current is calculated by multiplying a predetermined multiple according to the determination result of the accident aspect, and the 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 phase AC circuit The directional protection relay device according to claim 1, wherein the circuit breakers respectively installed in the first to third phases 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 determination means is configured to _detect a voltage value and 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 three-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 composite voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the three-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 composite voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the three-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 composite voltage input from the accident aspect determination transformer and the phase of the short-circuit current (I _Ry ) input from the three-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 three-phase through current transformer (10) is installed in the transmission and distribution line;
The second phase of the transmission / distribution line is penetrated through the annular core of the three-phase through current transformer by the same number of times in the opposite direction to the first phase, and the third phase of the transmission / distribution line is the first phase. Has been penetrated a different number of times in the same direction as
When the direction protection relay detects a short-circuit fault based on a short-circuit current (I _Ry ) input from the three-phase through current transformer and voltage information of the transmission / distribution line, the first to the first of the transmission / distribution line It is a short-circuit direction relay (4) that collectively shuts off the _first to _third circuit breakers (2 ₁ to 2 ₃ ) respectively installed in the third phase.
The direction protection relay device according to any one of claims 1 to 8, characterized in that. The three-phase through current transformer (10) is installed in the transmission and distribution line;
The second phase of the transmission / distribution line is penetrated through the annular core of the three-phase through current transformer by the same number of times in the opposite direction to the first phase, and the third phase of the transmission / distribution line is the first phase. Has been penetrated a different number of times in the same direction as
When the direction protection relay detects a short-circuit accident based on the short-circuit current (I _Ry ) input from the three-phase through current transformer and the voltage information of the transmission / distribution line, the first to the first of the transmission / distribution line A distance relay (20) that collectively shuts off _first to _third circuit breakers (2 ₁ to 2 ₃ ) respectively installed in the third phase;
The direction protection relay device according to any one of claims 1 to 8, characterized in that. Shorting the distance relay is input from the claims 6 to 8 or accident aspects the composite voltage than obtained correction voltage inputted from the determining transformer (V _Ry) and the three-phase through current transformer according to 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 three-phase through current transformers are first and second three-phase through current transformers (10 ₁ , 10 ₂ ) installed in the first and second transmission and distribution lines (1L, 2L), respectively.
The second phase of the first transmission / distribution line is passed through the annular core of the first three-phase through current transformer the same number of times in the opposite direction to the first phase, and the first transmission / distribution line The third phase is penetrated a different number of times in the same direction as the first phase,
The second phase of the second transmission / distribution line is passed through the annular core of the second three-phase through current transformer the same number of times in the opposite direction to the first phase, and the second transmission line The third phase of the distribution line is penetrated a different number of times in the same direction as the first phase;
The directional protection relay is a short-circuit current (I _Ry ) that is a difference between a short-circuit current input from the first three-phase through current transformer and a short-circuit current input from the second three-phase through current transformer. And the voltage information of the transmission / distribution line are detected in the first to third phases of the first transmission / distribution line when it is detected that a short circuit accident has occurred in the first transmission / distribution line. The first to third circuit breakers (2 ₁ to 2 ₃ ) were collectively cut off, and a short circuit accident occurred in the second transmission and distribution line based on the short circuit current and the voltage information of the transmission and distribution line. Is detected, the line selection relay (30) that collectively shuts off the _fourth to _sixth circuit breakers (2 ₄ to 2 ₆ ) installed in the first to third phases of the second transmission and distribution line, respectively. Is,
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 second phase of the three-phase AC circuit is passed through the annular core around which the secondary coil is wound in the same or different number of times in the opposite direction to the first phase, and the third phase of the three-phase AC circuit is passed through the first phase. A three-phase through current transformer (10) that is penetrated a different number of times in the same direction as one phase;
When a reverse power flow is detected based on the current (i _Ry ) input from the three-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 ) respectively installed in the first to third phases of the three-phase AC circuit;
A power direction relay device comprising: The power direction relay multiplies the current input from the three-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 three-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.