JP2008263761A - Power line artificial ground fault testing system and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power line artificial ground fault testing system and a power line artificial ground fault testing method having no danger of electric shock of an operator and capable of remarkably reducing a working time. <P>SOLUTION: The power line artificial ground fault testing system 1 includes a surge absorber 10 equipped with first-third switches 11<SB>1</SB>-11<SB>3</SB>provided on a secondary side of a voltage transformer 105 and provided in series on a capacitor C of each phase; and a test device 120 for testing a plurality of ground fault direction relays 135<SB>1</SB>-135<SB>3</SB>provided on a plurality of power distribution lines 102<SB>1</SB>-102<SB>3</SB>on the basis of a zero-phase voltage V<SB>0</SB>from a voltage transformer 103 for a grounding type gauge, a ground current I<SB>g</SB>from the surge absorber 10 and zero-phase currents I<SB>01</SB>-I<SB>03</SB>from a plurality of zero-phase current transformers 134<SB>1</SB>-134<SB>3</SB>. The testing system executes a ground fault test on the plurality of ground fault direction relays 135<SB>1</SB>-135<SB>3</SB>by opening at least one of the first-third switches 11<SB>1</SB>-11<SB>3</SB>to break the balance of anti-ground electrostatic capacity of the plurality of power distribution lines 102<SB>1</SB>-102<SB>3</SB>. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a distribution line artificial ground fault test apparatus and a distribution line artificial ground fault test method, and in particular, performs a primary test of a plurality of ground fault direction relays using a surge absorber installed on a secondary side of a transformer. The present invention relates to a distribution line artificial ground fault test apparatus and a distribution line artificial ground fault test method suitable for performing.

  The settling value (operating point) of the ground fault relay (DG), which is a ground fault protective relay for operating the circuit breaker (CB) in the event of a ground fault in the distribution line, is determined based on the characteristics of the ground line However, since the length of the distribution line changes every year, it is necessary to adjust the set value of the ground fault direction relay. Therefore, the electric power company conducts a distribution line artificial ground fault test once a year to adjust the set value of the ground fault direction relay.

  Conventionally, such a distribution line artificial ground fault test has been performed using a ground fault generator 110, a tester 120, and a connection line 130 as shown in FIG.

  Ground fault generator 110 is for artificially generating a ground fault in one phase (here, red phase R) of bus 101 of three phases (red phase R, white phase W and blue phase B), Contact rod 111, switch 112 with an input terminal connected to contact rod 111, power fuse 113 with one terminal connected to the output terminal of switch 112, and one terminal connected to the other terminal of power fuse 113 The ground fault resistor 114 (ground fault resistance = 3,000Ω) and a ground circuit 115 including a current transformer are provided.

Tester 120 is provided to the bus 101 when inwardly Test (Test at own line accident) and outward testing of the first to third ground directional relay 135 _{1-135 3} (test during other line accident) was grounded potential transformer (GPT) 103 zero-phase voltage V ₀ which is input from the ground fault current I _g and the first to third zero-phase inputted from the ground circuit 115 of the earth絡発generating device 110 Based on the first to third zero-phase currents I _{01 to} I ₀₃ input from the flow devices (ZCT) 134 _{1 to} 134 ₃ , the first to third ground fault direction relays 135 _{1 to} 135 ₃ are tested. Is to do.

First, in order to perform the internal direction test of the first earth fault directional relay 135 _1, worker, toward the first end of the distribution line 102 ₁ ground fault current I _g is from bus 101 (i.e., rightward The connecting wire 130 is connected to the first test through wire 137 ₁ of the first zero-phase current transformer 134 _{1 so} as to flow. Here, the first zero-phase current transformer 134 ₁ is provided between the _two disconnectors (DS) 131 ₁ and 131 ₂ , and the first circuit breaker 133 ₁ is the disconnector on the bus bar 101 side. It is provided between 131 ₁ and the first zero-phase current transformer 134 ₁ .

Thereafter, the worker brings the contact bar 111 of the ground fault generating device 110 into contact with the red phase R of the bus 101 and then presses the switch 112 only for an instant. As a result, the red phase R of the bus 101 is artificially grounded, and the first to third primary currents I _{1 to} I ₃ are supplied to the first to _third distribution lines 102 _{1 to} 102 ₃ . The first to third distribution lines 102 _{1 to} 102 ₃ flow toward the bus 101 (ie, in the left direction in the figure), respectively.
Also, the ground fault current I _g (= I ₁ + I ₂ + I ₃ ), which is a combined current of the _{first to third} primary currents I _{1 to} I ₃ , is the bus 101 → contact bar 111 → switch 112 → power fuse 113. → Ground fault resistor 114 → connection line 130 → first test through wire 137 ₁ → connection line 130 → ground circuit 115.
At this time, since the first zero-phase current transformer 134 ₁ first primary current I ₁ flows in the direction opposite to the ground fault current I _g, the first primary current I from the ground fault current I _{g A first} zero-phase current I ₀₁ corresponding to the current I _g −I ₁ (= I ₂ + I ₃ ) minus ₁ is input to the _first ground fault direction relay 135 ₁ .

Tester 120 includes a ground fault current I _g is inputted from the ground circuit 115, the zero-phase voltage V ₀ which is input from the earth type potential transformer 103, first from the first zero-phase current transformer 134 ₁ The first zero-phase current I ₀₁ inputted through the ground fault direction relay 135 ₁ is measured.

When the internal direction test of the _first ground fault direction relay 1351 is completed in this way, the worker separates the contact bar 111 from the red phase R of the bus bar 101 and also connects the connection line 130 to the first test penetration line. remove from the 137 _1.

Subsequently, in order to perform the external direction test of the _first ground fault direction relay 1351, the worker connects both ends of the connection line 130 and directly connects the ground fault resistor 114 and the ground circuit 115.
Thereafter, the worker brings the contact bar 111 into contact with the red phase R of the bus bar 101 for a predetermined time, and then presses the switch 112 for an instant. As a result, the red phase R of the bus 101 is artificially grounded, and the first to third primary currents I _{1 to} I ₃ are supplied to the first to _third distribution lines 102 _{1 to} 102 ₃ . The first to third distribution lines 102 _{1 to} 102 ₃ flow from the ends toward the bus bar 101, respectively.
Also, the ground fault current I _g (= I ₁ + I ₂ + I ₃ ), which is a combined current of the _{first to third} primary currents I _{1 to} I ₃ , is the bus 101 → contact bar 111 → switch 112 → power fuse 113. → Ground fault resistor 114 → Connection line 130 → Ground current circuit 115.
At this time, since only the first primary current I ₁ flows through the first zero-phase current transformer 134 ₁ , the first zero-phase current I ₀₁ corresponding to the first primary current I ₁ is the first input of the earth fault direction relay 135 _1.

Tester 120 includes a ground fault current I _g is inputted from the ground circuit 115, the zero-phase voltage V ₀ which is input from the earth type potential transformer 103, first from the first zero-phase current transformer 134 ₁ The first zero-phase current I ₀₁ inputted through the ground fault direction relay 135 ₁ is measured.
Tester 120 is ground fault current I _g were measured in the inward direction test, the zero-phase voltage V ₀ and the first zero-phase current I _01, the ground fault current I _g as measured in an external direction test, the zero-phase voltage V ₀ Then, the set value of the _first ground fault direction relay 1351 is adjusted based on the first zero-phase current I ₀₁ . The tester 120 outputs the test zero-phase voltage V ₀ ′ and the first test zero-phase current I ₀₁ ′ corresponding to the adjusted set value to the first ground fault direction relay 135 ₁ , and to confirm the first earth fault directional relay 135 ₁ response operation based on the first relay contact operation signals S ₁ inputted from the ground directional relay 135 _1.

In this manner, when the first ground fault directional relay 135 ₁ test is completed, the worker, the second by performing in the same manner as the internal direction test and outward testing of the second earth fault directional relay 135 ₂ After tested for earth fault directional relay 135 _2, testing the third ground directional relay 135 ₃ by performing in the same manner as the internal direction test and outward testing of the third ground directional relay 135 ₃ .

In addition, in the following Patent Document 1, the artificial ground fault test is semi-automated, and the open / close control of the ground fault device that causes the distribution line to artificially ground is performed in order to reduce the amount of work, shorten the test time, and prevent danger. A ground fault device control unit, a measurement unit that performs high-speed sampling of zero phase voltage, ground fault current, etc., and generates a simulated zero phase voltage and simulated ground fault current as a ground fault protection relay test signal. The relay test circuit unit that measures the operating value of the circuit, and controls each of these units, performs predetermined calculations on the output data of the measurement unit, and determines the ground fault characteristics of the line that is the basic data for generating the test signal There is disclosed a distribution line artificial ground fault testing apparatus that includes a microcomputer section and instantaneously grounds a distribution line to measure ground line characteristics and perform an operation test of a ground fault protection relay.
Japanese Patent Laid-Open No. 2-105073

However, in the distribution line artificial ground fault test method as described above, the external direction test of one distribution line can be performed in combination with the internal direction test of distribution lines other than this distribution line. Because there is a need to artificially generate a ground fault as many times as there are, there has been a problem in that the voltage on the ground is repeatedly applied to the operating distribution line and there is a risk of electric shock of the worker.
In addition, when performing an internal direction test of a ground fault direction relay, it takes time to connect the connection line of the ground fault generator to the test through line of the zero-phase current transformer of each distribution line, which is not efficient. In addition, there was a problem of miswiring.

  An object of the present invention is to provide a distribution line artificial ground fault test apparatus and a distribution line artificial ground fault test method that can reduce the work time without risk of electric shock of workers.

The distribution line artificial ground fault test apparatus of the present invention is a first installed on the secondary side of the transformer (105) provided on the bus (101) and provided in series with each phase capacitor (C). Thru-phase voltage input from a surge absorber (10) having _third to _third switches (11 _{1 to} 11 ₃ , 51 _{1 to} 51 ₃ ) and a grounded instrument transformer (103) provided on the bus. (V ₀ ), a ground current (I _G ) input from the surge absorber, and a plurality of zero-phase current transformers (134 ₁ ) provided in a plurality of distribution lines (102 _{1 to} 102 ₃ ) of the bus system. ～134 ₃₎ based on the zero-phase current input (I ₀₁ ~I ₀₃₎ from, for testing a plurality of ground directional relay respectively provided to the plurality of distribution line (135 ₁ to 135 ₃₎ And the first tester (120). At least one of the third switch open and performs ground fault test of the plurality of earth fault directional relay by breaking the balance of the earth capacitance of the plurality of distribution lines.
Here, a serial through wire (20) may be further provided, both ends of which are respectively connected to the output terminal of the surge absorber and the tester and penetrate the plurality of zero-phase current transformers.
The series through-wires respectively penetrate the plurality of zero-phase current transformers so that the ground current flows through the plurality of zero-phase current transformers from the bus line toward the ends of the plurality of distribution lines. It may be.
The first to third switches (11 _{1 to} 11 ₃ ) may be two-terminal switches that are controlled to be opened and closed by the tester.
The first to third switches (11 _{1 to} 11 ₃ ) are three-terminal switches that are controlled to open and close by the tester, and the first output terminals (a) of the first to third switches are grounded. The second output terminals (b) of the first to third switches may be connected.
A test switch (13) having an input terminal connected to the surge absorber; and a ground circuit (12) connected to a second output terminal of the test switch; One end is connected to the first output terminal of the test switching switch, the other end of the series through wire is connected to the second output terminal of the test switching switch, and the ground current is supplied from the ground circuit to the second output terminal. It may be output to a tester.
A test changeover switch (33) whose input terminal is connected to the surge absorber, and a ground circuit (12) connected to the output terminal of the test changeover switch, wherein one end of the series through-wire is The test switching switch may be connected to the input terminal, the other end of the series through wire may be connected to the output terminal of the test switching switch, and the ground current may be output from the ground circuit to the tester. .
When there is a reactor grounding distribution line, reactance varying means capable of changing the reactance of the petenzel coil of the bus may be further provided.
The surge absorber may include one switch provided in series with a representative phase capacitor instead of the first to third switches.

The distribution line artificial ground fault test method of the present invention includes at least one of the capacitors (C) of each phase of the surge absorber (10) installed on the secondary side of the transformer (105) provided on the bus (101). One is opened to break the balance of the ground capacitance of the plurality of distribution lines (102 _{1 to} 102 ₃ ) of the system of the bus and is inputted from the grounded instrument transformer (103) provided on the bus Zero-phase voltage (V ₀ ), ground current (I _G ) input from the surge absorber, and a plurality of zero-phase current transformers (134 _{1 to} 134 ₃ ) respectively provided in the plurality of distribution lines. On the basis of the zero-phase currents (I _{01 to} I ₀₃ ), a ground fault test is performed on a plurality of ground fault direction relays (135 _{1 to} 135 ₃ ) respectively provided on the plurality of distribution lines.
Here, when performing an internal direction test of the plurality of ground fault direction relays, a series through wire (20) penetrating the ground current (I _G ) from the surge absorber through the plurality of zero-phase current transformers. When the ground current is caused to flow through the plurality of zero-phase current transformers from the bus to the ends of the plurality of distribution lines, and the external direction test of the plurality of ground fault direction relays is performed. May not output the ground current to the series through-line.

The distribution line artificial ground fault test apparatus and the distribution line artificial ground fault test method of the present invention have the following effects.
(1) Since the hot wire work can be eliminated, the danger of an electric shock to the worker can be eliminated.
(2) It is not necessary to connect or disconnect the connection line 130 shown in FIG. 5 to the first to third test through-lines 137 _{1 to} 1373, and the _{first to third} provided in the surge absorber Since the internal direction test and the external direction test of a plurality of ground fault direction relays can be performed only by operating the switch, the working time can be greatly shortened. Further, the working time can be further shortened by controlling the first to third switches by the tester.
(3) Since existing facilities can be used, capital investment can be reduced.
(4) Since the DC component is not included in the zero-phase voltage at the start of the test, the test can be performed without waiting for the attenuation of the DC component.

  A plurality of ground fault direction relays by opening at least one of the capacitors of each phase of the surge absorber installed on the secondary side of the transformer to break the balance of the ground capacitance of the plurality of distribution lines. It was realized by conducting a ground fault test.

Hereinafter, embodiments of the distribution line artificial ground fault test apparatus and the distribution line artificial ground fault test method of the present invention will be described with reference to the drawings. In addition, three ground fault direction relays (first to third ground fault direction relays 135 ₁ ) respectively provided on the three distribution lines (first to third distribution lines 102 _{1 to} 102 ₃ ) of the system of the bus bar 101. ˜135 ₃ ) will be described as an example.

As shown in FIG. 1, a distribution line artificial ground fault testing apparatus 1 according to an embodiment of the present invention is installed on the secondary side of a transformer 105 provided on a bus 101 and is connected in series with a capacitor C of each phase. A surge absorber (SA) 10 including _first to _third switches 11 _{1 to} 11 ₃ provided, a tester 120, a series through wire 20, a ground circuit 12, and a test switching switch 13, respectively. It has.
Here, the surge absorber 10 is obtained by providing _first to _third switches 11 _{1 to} 11 ₃ to a conventional surge absorber for preventing zero-phase voltage transition for removing a lightning surge voltage. The capacitance value of the capacitor C of the surge absorber 10 is, for example, 0.3 μF for the 6.6 kV system and 0.15 μF for the 22 kV system.
The first to third switches 11 _{1 to} 11 ₃ are two-terminal switches that are controlled to be opened and closed by _{first to third} switch control signals SW _{1 to} SW 3 input from the tester 120, respectively. The output terminal of the surge absorber 10 is connected to the input terminal of the test switching switch 13.

The tester 120 includes a zero-phase voltage V ₀ input from a grounded instrument transformer 103 provided on the bus 101 and a ground current I input from the surge absorber 10 via the series through wire 20 and the ground circuit 12. _G and first to third zero-phase currents input from _{first to third} zero-phase current transformers 134 _{1 to} 134 3 provided in the first to _third distribution lines 102 _{1 to} 102 ₃ , respectively. This is for testing the _{first to third} ground fault direction relays 135 _{1 to} 1353 based on I _{01 to} I ₀₃ .

One end of the serial through wire 20 is connected to the first output terminal of the test switching switch 13, and the other end of the serial through wire 20 is connected to the second output terminal of the test switching switch 13. Thus, by controlling the test switching switch 13 by the fourth switch control signal SW ₄ from the tester 120, or may not flow or flow of ground current I _G output from a surge absorber 10 in series through line 20 can do.
Series through line 20, the first ground current I _G output from the output terminal is the first to the bus 101 first to third zero-phase current transformer 134 _{1-134 3} test changeover switch 13 3 towards the end of the distribution line 102 _{1-102 3} to flow (i.e., rightward direction), respectively, extend through the first to third zero-phase current transformer 134 _{1-134 3.}

Next, using the distribution line artificial ground fault test apparatus 1 according to the present embodiment, the first to third ground fault direction relays 135 ₁ to 135 ₁ provided in the first to _third distribution lines 102 _{1 to} 102 ₃ , respectively. It describes a method of performing 135 ₃ tests.

First, in order to perform an internal direction test of the _{first to} third ground fault direction relays 135 _{1 to} 135 ₃ , the tester 120 controls the connection between the input terminal and the first output terminal. After outputting the switch control signal SW ₄ to the test switching switch 13, the first switch control signal SW ₁ for opening the first switch 11 ₁ of the surge absorber 10 is output to the first switch 11 ₁ .
Thus, first to third and the balance of the earth capacitance of the red phase R of the distribution line 102 _{1-102 3} is collapsed, the first to third distribution line 102 _{1-102 3,} first The third primary currents I _{1 to} I ₃ flow from the ends of the _{first to third} distribution lines 102 _{1 to} 102 ₃ toward the bus bar 101 (that is, in the left direction in the drawing).
Further, the ground current I _G (= I ₁ + I ₂ + I ₃ ) corresponding to the combined current of the _{first to third} primary currents I _{1 to} I ₃ is the surge absorber 10 → the input terminal of the test switching switch 13 → The first output terminal of the test switching switch 13 → the series through line 20 → the first zero-phase current transformer 134 ₁ → the series through line 20 → the second zero-phase current transformer 134 ₂ → the series through line 20 → the first 3 zero-phase current transformer 134 ₃ → the series through-line 20 → the second output terminal of the test switching switch 13 → the ground circuit 12.

At this time, since the first zero-phase current transformer 134 ₁ first primary current I ₁ flows in a direction opposite to the ground current I _G, the first primary current I ₁ from the ground current I _G A first zero-phase current I ₀₁ corresponding to the drawn current I _G −I ₁ (= I ₂ + I ₃ ) is input to the _first ground fault direction relay 135 ₁ .
Further, since the second primary current I ₂ flows in the opposite direction to the ground current I _G, minus the second primary current I ₂ from the ground current I _G in _Paragraph 2 of ZCT 134 The second zero-phase current I ₀₂ corresponding to the current I _G −I ₂ (= I ₃ + I ₁ ) is input to the _second ground fault direction relay 1352.
Further, the third zero-phase current transformer 134 ₃ to flow the third primary current I ₃ in a direction opposite to the ground current I _G, minus the third primary current I ₃ from the ground current I _G The third zero-phase current I ₀₃ corresponding to the current I _G −I ₃ (= I ₁ + I ₂ ) is input to the _third ground fault direction relay 1353.

Tester 120 includes a ground current I _G to be inputted from the ground circuit 12, the zero-phase voltage V ₀ which is input from the earth type potential transformer 103, first to third zero-phase current transformer 134 ₁ from 134 ₃ via the first to third ground directional relay 135 _{1-135 3} measures and first to third zero-phase current I ₀₁ ~I ₀₃ is input.

Subsequently, in order to perform an external direction test of the _{first to} third ground fault direction relays 135 _{1 to} 135 ₃ , the tester 120 performs control to connect the input terminal and the second output terminal. After the switch control signal SW ₄ is output to the test switching switch 13, the first switch control signal SW ₁ for opening the first switch 11 ₁ of the surge absorber 10 is output to the first switch 11 ₁ .
Thus, first to third and the balance of the earth capacitance of the red phase R of the distribution line 102 _{1-102 3} is collapsed, the first to third distribution line 102 _{1-102 3,} first The third primary currents I _{1 to} I ₃ flow from the ends of the _{first to third} distribution lines 102 _{1 to} 102 ₃ toward the bus bar 101 (that is, in the left direction in the drawing).
The ground current I _G (= I ₁ + I ₂ + I ₃ ), which is a combined current of the _{first to third} primary currents I _{1 to} I ₃ , is the surge absorber 10 → the input terminal of the test switching switch 13 → the test. The current flows from the second output terminal of the switching switch 13 to the ground circuit 12.

At this time, the ground current I _G, since not output in series through line 20, does not flow through the first to third zero-phase current transformer 134 _{1-134 3.}
Accordingly, since only the first primary current I ₁ flows through the first zero-phase current transformer 134 ₁ , the first zero-phase current I ₀₁ corresponding to the first primary current I ₁ is is input to the ground directional relay 135 _1.
Since only the _second primary current I ₂ flows through the second zero-phase current transformer 134 ₂ , the second zero-phase current I ₀₂ corresponding to the second primary current I ₂ is is input to the ground directional relay 135 _2.
Furthermore, since only the _third primary current I ₃ flows through the third zero-phase current transformer 134 ₃ , the third zero-phase current I ₀₃ corresponding to the third primary current I ₃ becomes the third is input to the ground directional relay 135 _3.

Tester 120 includes a ground current I _G to be inputted from the ground circuit 12, the zero-phase voltage V ₀ which is input from the earth type potential transformer 103, first to third zero-phase current transformer 134 ₁ from 134 ₃ via the first to third ground directional relay 135 _{1-135 3} measures and first to third zero-phase current I ₀₁ ~I ₀₃ is input.
The tester 120 includes a ground current I _G , zero phase voltage V ₀ and first to third zero phase currents I _{01 to} I ₀₃ measured in the internal direction test, and a ground current I _G measured in the external direction test, zero. to phase voltages V ₀ and the 1 on the basis of the third zero-phase current I ₀₁ ~I _03, to adjust the first to third setting value of earth fault directional relay 135 _{1-135 3.} The tester 120 outputs the test zero-phase voltage V ₀ ′ and the first to third test zero-phase currents I ₀₁ ′ to I ₀₃ ′ corresponding to the adjusted set value to the first to third ground fault direction relays. First to third relay contact operation signals S _{1 to} S ₃ output to 135 _{1 to} 135 ₃ and input from the first to third ground fault direction relays 135 _{1 to} 135 ₃ , respectively. To the third ground fault direction relays 135 _{1 to} 135 ₃ are confirmed. This makes it possible to collectively test of the first to third ground directional relay 135 _{1-135 3.}

In the above description, the first switch 11 ₁ of the surge absorber 10 is opened, and the first to third ground fault direction relays 135 ₁ to 135 ₁ for the red phase R of the first to _third distribution lines 102 _{1 to} 102 _3. 135 were subjected to ₃ tests, for the first through third white phase W and Aosho B distribution lines 102 ₁ to 102 _3, the test of the first to third ground directional relay 135 _{1-135 3} Each can be performed similarly.
In addition, the tester 120 does not balance the ground capacitance of the red phase R, the white phase W, and the blue phase B of the _{first to third} distribution lines 102 _{1 to} 102 3 only by opening the _first switch 11 _1. If the first to third ground fault direction relays 135 _{1 to} 135 ₃ do not operate, the second switch control signal SW ₂ for opening the second switch 11 ₂ of the surge absorber 10 is used as the second switch. outputs 11 _2, still in the case where the first to third ground directional relay 135 _{1-135 3} does not work, the third switch control signal SW ₃ to open the third switch 11 ₃ of the surge absorber 10 the third switch 11 by disconnecting the surge absorber 10 from the bus 101 by opening all of the first through third switches 11 ₁ to 11 ₃ and outputs _three, first to third ground directional relay 135 ₁ ~ 13 5 ₃ of the study can be performed, respectively.

As described above, according to the distribution line artificial ground fault test apparatus 1 according to the present embodiment, the first to third ground faults can be obtained simply by opening the _first to _third switches 11 _{1 to} 11 ₃ of the surge absorber 10. Since the direction relays 135 _{1 to} 135 ₃ can be tested, the working time can be greatly reduced. In addition, since it is not necessary to generate a ground fault in the red phase R of the bus bar 101 using the contact rod, it is possible to eliminate the risk of an operator being electrocuted.

Further, as shown in FIG. 1, the first to fourth switch control signals SW _{1 to} SW ₄ are output from the tester 120 to the _first to _third switches 11 _{1 to} 11 ₃ and the test switching switch 13, respectively. Then, by controlling the _first to _third switches 11 _{1 to} 11 ₃ and the test switching switch 13 by the tester 120, the working time can be further shortened. At this time, first to third switches 11 ₁ to 11 ₃ and the first to fourth switch state signal indicative of the state of the test switching switch 13 first to third switches 11 ₁ to 11 ₃ and the test switch By outputting to the tester 120 from the switch 13 for testing, the tester 120 can monitor the states of the _first to _third switches 11 _{1 to} 11 ₃ and the test switching switch 13 and can display them externally. May be.

Further, as shown in FIG. 2 (a) and FIG. 2 (b), as an example of simulation results, the zero phase when the two-phase capacitor of the surge absorber 10 is opened and when one phase is grounded with a ground fault resistance of 3000Ω. When comparing the time variation of the voltage V _0, but does not include a DC component to zero-phase voltage V ₀ in the former, the latter contains a DC component in the zero-phase voltage V ₀ at the start of the study. Therefore, when a test is performed with one phase grounded with a ground resistance of 3000Ω, it is necessary to wait for the DC component of the zero-phase voltage V ₀ to decay, but the capacitor of the surge absorber 10 is opened. When performing the test, it is not necessary to wait for the DC component of the zero-phase voltage V ₀ to be attenuated, so that the working time can be shortened.

In the above description, the surge absorber 10 having three switches ( _first to _third switches 11 _{1 to} 11 ₃ ) is used, but instead of the _first to _third switches 11 _{1 to} 11 ₃ . By using a surge absorber provided with one switch provided in series with the capacitor C of the representative phase, the test equipment may be made slim.
Further, although the surge absorber 10 including the _first to _third switches 11 _{1 to} 11 ₃ which are two-terminal switches is used, the first to third switches 51 ₁ which are three-terminal switches as shown in FIG. to 51 ₃ may be used a surge absorber 50 provided with. In this case, the first output terminal a of the first to _third switches 51 _{1 to} 51 ₃ is grounded, and one end of the series through wire 20 is connected to the first of the first to third switches 51 _{1 to} 51 ₃ . By connecting to the two output terminals b, the test switching switch 13 can be dispensed with. In addition, as shown by a one-dot chain line in FIG. 3, the surge absorber 50 can be opened if all the _{first to third} switches 51 _{1 to} 51 ₃ can be controlled to the neutral positions.

Although a three-terminal switch is used as the test switching switch 13, one end of the series through wire 20 is used as an input terminal of the test switching switch 33 by using the test switching switch 33 that is a two-terminal switch as shown in FIG. The other end of the series through wire 20 may be connected to the output terminal of the test switching switch 33. In this case, opening the first to third ground directional relay 135 _{1-135 3} test changeover switch 33 when making an internal direction test, the first to third ground directional relay 135 _{1-135 3} When the external direction test is performed, the test switching switch 33 is closed. The test switching switch 33 may be opened and closed by an operator, or may be performed by the tester 120 using a _fourth switch control signal SW _{4 as} shown in FIG.

Although the serial through wire 20 is used, the connecting wire 130 shown in FIG. 5 may be used instead of the serial through wire 20.
The distribution line artificial ground fault test apparatus 1 may further include a reactance variable device that can change the reactance of the petenzel coil of the bus bar using the reactance control signal when there is a reactor ground distribution line. .

  As described above, the distribution line artificial ground fault test apparatus and the distribution line artificial ground fault test method of the present invention are, for example, a plurality of ground fault direction relays using a surge absorber installed on the secondary side of the transformer. Can be used to perform the primary test.

It is a figure which shows the structure of the distribution line artificial ground fault test apparatus 1 by one Example of this invention. Is a diagram illustrating an example of a simulation result, (a) is a diagram showing an example of a simulation result of the time variation of the zero-phase voltage V ₀ in the case of capacitors opened two-phase surge absorber 10, (b) is a diagram showing an example of a simulation result of the time variation of the zero-phase voltage V ₀ in the case where is ground one phase ground fault resistance 3000 ohms. First, a three-terminal switch is a diagram showing a configuration of a surge absorber 50 provided with a third switch 51 ₁ to 51 _3. It is a figure which shows the structure of the distribution line artificial ground fault test apparatus 1 'at the time of using the test switch 33 which is a 2 terminal switch. It is a figure which shows the structure of the conventional distribution line artificial ground fault test apparatus.

Explanation of symbols

1,1 'distribution line artificial ground fault testing apparatus 10, 50 surge absorber 11 _1, 51 ₁ the first switch 11 _2, 51 ₂ second switch 11 _3, 51 ₃ third switch 12 ground circuit 13 and 33 tests Switching switch 20 Series through-wire 101 Buses 102 _{1 to} 102 ₃ First to third distribution lines 103 Grounded instrument transformer 105 Transformer 120 Tester 131 _{1 to} 131 ₃ , 132 _{1 to} 132 ₃ Disconnector 133 ₁ ˜133 ₃ First to third circuit breakers 134 ₁ ˜134 ₃ First to third zero phase current transformers 135 ₁ ˜135 ₃ First to third ground fault direction relay 136 Ground fault overvoltage relay R Red phase W White phase B Blue phase C Capacitor V ₀ Zero phase voltage V ₀ ′ Test zero phase voltage I _{01 to} I ₀₃ First to third zero phase current I ₀₁ ′ to I ₀₃ ′ First to third test zero phase current I _g grounding current I _G ground current SW ₁ to SW ₄ first through Switch control signal T ₁ through T ₃ first through third trip signal

Claims (11)

First to third switches (11 _{1 to} 11) provided on the secondary side of the transformer (105) provided on the bus (101) and provided in series with the capacitors (C) of the respective phases. ₃ , 51 _{1 to} 51 ₃ ), and a surge absorber (10),
A zero-phase voltage (V ₀ ) input from a grounded-type instrument transformer (103) provided on the bus, a ground current (I _G ) input from the surge absorber, and a plurality of systems of the bus based on the zero-phase current inputted from the distribution line (102 ₁ to 102 ₃₎ a plurality of zero-phase current transformer provided respectively to _{(134 1 ~134 3) (I} 01 ~I 03), distribution of the plurality of A tester (120) for testing a plurality of ground fault direction relays (135 _{1 to} 135 ₃ ) respectively provided on the electric wires;
Comprising
Performing a ground fault test of the plurality of ground fault direction relays by opening at least one of the first to third switches to break the balance of the ground capacitance of the plurality of distribution lines;
A distribution line artificial ground fault testing device.   2. A series through wire (20) having both ends connected to the output terminal of the surge absorber and the tester respectively and penetrating the plurality of zero-phase current transformers, further comprising: The distribution line artificial ground fault test equipment described.   The series through-wires respectively penetrate the plurality of zero-phase current transformers so that the ground current flows through the plurality of zero-phase current transformers from the bus line toward the ends of the plurality of distribution lines. The distribution line artificial ground fault testing apparatus according to claim 2, wherein The distribution line artificial ground according to any one of claims ₁ to ₃ , wherein the _first to _third switches (11 _{1 to} 11 ₃ ) are two-terminal switches controlled to be opened and closed by the tester. Tangle test equipment. The first to third switches (11 _{1 to} 11 ₃ ) are three-terminal switches that are controlled to open and close by the tester,
The first output terminals (a) of the first to third switches are grounded;
A second output terminal (b) of the first to third switches is connected;
The distribution line artificial ground fault testing apparatus according to any one of claims 1 to 3, wherein A test changeover switch (13) whose input terminal is connected to the surge absorber;
A ground circuit (12) connected to the second output terminal of the test switching switch;
Further comprising
One end of the series through wire is connected to the first output terminal of the test switching switch, and the other end of the series through wire is connected to the second output terminal of the test switching switch,
The ground current is output from the ground circuit to the tester;
The distribution line artificial ground fault testing apparatus according to any one of claims 2 to 5, wherein A test changeover switch (33) having an input terminal connected to the surge absorber;
A ground circuit (12) connected to the output terminal of the test switching switch;
Further comprising
One end of the series through wire is connected to the input terminal of the test switching switch, and the other end of the series through wire is connected to the output terminal of the test switching switch,
The ground current is output from the ground circuit to the tester;
The distribution line artificial ground fault testing apparatus according to any one of claims 2 to 5, wherein   The distribution line according to any one of claims 1 to 7, further comprising reactance varying means capable of changing a reactance of a petenzel coil of the busbar when there is a reactor grounding distribution line. Artificial ground fault test equipment.   9. The distribution according to claim 1, wherein the surge absorber includes one switch provided in series with a representative phase capacitor instead of the first to third switches. 10. Electric wire artificial ground fault test equipment. At least one of the capacitors (C) of each phase of the surge absorber (10) installed on the secondary side of the transformer (105) provided on the bus (101) is opened, and a plurality of bus systems are provided. The balance of the electrostatic capacity of the distribution lines (102 _{1 to} 102 ₃ )
A zero-phase voltage (V ₀ ) input from a grounded instrument transformer (103) provided on the busbar, a ground current (I _G ) input from the surge absorber, and the plurality of distribution lines, respectively A plurality of ground fault directions respectively provided in the plurality of distribution lines based on zero phase currents (I _{01 to} I ₀₃ ) input from the plurality of zero phase current transformers (134 _{1 to} 134 ₃ ) provided. Conduct a ground fault test for relays (135 _{1 to} 135 ₃ ),
A distribution line artificial ground fault test method characterized by the above. When performing an internal direction test of the plurality of ground fault direction relays, the ground current (I _G ) from the surge absorber is output to a series through-line (20) that penetrates the plurality of zero-phase current transformers. And flowing the ground current through the plurality of zero-phase current transformers from the bus to the ends of the plurality of distribution lines,
When performing an external direction test of the plurality of ground fault direction relays, do not output the ground current to the series through wire,
The distribution line artificial ground fault test method according to claim 10, wherein:

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