JPH0819158A - Automatic sectional switch - Google Patents

Abstract

PURPOSE:To shorten the power failure section and time by setting the individual delay time of a high voltage switch, which is installed in each section point of a plurality of power distribution sections of the time limit forward transmission type power distribution line, shorter than the operating time of the ground-failure protection relay in the power substation and longer than the operating time of the short-circuit protection relay having the anti-limit time characteristic. CONSTITUTION:An automatic section switch provided at each section point of the power distribution line of the time-limit forward transmission system is composed of a high voltage switch S and a control box T. The switch S is provided with a zero-phase current transformer ZCT, a zero-phase transformer ZPD, a switch M and a delay circuit 3 consisting of a resistor R and 6 a diode D1. The control box T is provided with a ground-fault direction relay E operating with outputs of ZCT, ZPD, relay G and F sequentially interlocking with the relay E and an automatic sectional apparatus H. The delay time of relay circuit 3 is shorter than the operating time of the ground-fault protection relay in the substation and longer than the operating time of the short-circuit protection relay of the anti-limit time characteristic and is usually set to about 0.6 second. Thereby, the power failure section and time when a fault occurs can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic switchgear arranged and used in a power distribution section of a time-sequential distribution line, when a ground fault, a short circuit failure or the like occurs in the power distribution section. The failure can be automatically detected and detected, and based on the selection detection, the faulty distribution section can be automatically opened and cut off from the healthy section on the substation side.

[0002]

2. Description of the Related Art A time-sequential type distribution line is shown in FIG.
Automatic division switches B ₂ , B ₃ ... are arranged at the division points of a large number of distribution sections A ₁ , A ₂ ..., and when the circuit breaker CB of the substation is closed, automatic division switches B ₂ , B ₃ ..., but from automatic subdivision switch B ₁ on the substation side to automatic subdivision switch B on the load side
_2, B ₃ sequentially ..., are turned on with a turned time difference is predetermined, it is to be successively transmitted from the power distribution leg A ₁ substation side to the final distribution leg A _n.

In such a time-progressive type distribution line 1, a ground fault due to a poor insulation of a transformer, a ground fault due to a poor insulation of a pillar insulator supporting a high-voltage distribution line, a strong wind or a bird. Various ground faults such as a ground fault caused by contact with the above may occur. In addition, a short circuit failure may occur due to poor insulation of the cable itself. In recent years, of these failures, short-circuit failures have become extremely small with the improvement of cable quality, only 10 to 20%, and the remaining 8 failures.
0 to 90% is a ground fault.

[0004]

[Normal power transmission] In the time-progress type distribution line shown in Fig. 4, power is transmitted from the substation to the high-voltage distribution line as follows. (1) When the CB (circuit breaker) of the feeder F1 at the substation is closed, power is transmitted to the distribution section A ₁ and the automatic section switches B ₁ and B
Voltage is applied to ₅ . (2) The automatic sorting switch B ₁ is turned on after a predetermined closing time (eg, 7 seconds) and power is transmitted to the distribution section A ₂ . (3) below, the distribution leg A ₂ after the automatic section switch B _2,
B ₃ ... are sequentially put in with the above-mentioned time difference, 49
After a few seconds, power is transmitted to the final distribution section A ₈ .

In the time-progressive type distribution line 1 shown in FIG.
_{When a} short circuit or a ground fault occurs in any one of ₁ , ₁ , A _2, ..., It was processed as follows. (1) For example, when a short circuit or a ground fault occurs in the power distribution section A ₃ , the circuit breaker CB of the substation shuts off. Normally, the circuit breaker CB is set to be closed twice after the circuit breaker. In this case, the first closed path is called reclosed and the second closed path is called reclosed. (2) When the circuit breaker CB is reclosed after the circuit breaker CB is cut off and power is retransmitted to the distribution line, if the circuit breaker CB is cut off again and a power failure occurs again, the distribution section A ₃ is detected as a short circuit or a ground fault section. It At this time, the automatic classification switch B ₂ is locked in the cutoff state (it is kept in a state in which power is not transmitted to the load side even if the circuit is closed again after that), and the circuit breaker CB is closed again after that and the substation is closed. Even if power is transmitted to the distribution section A ₂ , the automatic section switch B ₂ is not turned on, and the accident section (distribution section A _{3 in} FIG. 4) is separated from the healthy section on the substation side. In this case, split off the distribution leg A ₃ and subsequent distribution leg is a power failure, but from healthy substations side power distribution segment A _1, A ₂ is not a power outage. (3) If the ground fault is not detected within the predetermined detection time during the reclosing, the automatic section switch B ₂
Returns to the normal state, the lock is released, and after the circuit is closed again, the power is sequentially turned on to the automatic section switches B ₃ , B _4, ...

[0006]

SUMMARY OF THE INVENTION The above-mentioned accident processing method has the following problems. ． If a short circuit or a ground fault occurs in any of the distribution sections A ₁ , A _2, ..., The circuit breaker CB of the substation will shut off.
All the power distribution sections after the circuit breaker CB will be out of power, and the healthy sections where no ground fault has occurred will also be out of power. Moreover,
Since a power failure occurs even when the ground fault section is separated from a sound section, if a ground fault occurs, a power failure occurs at least twice before power can be transmitted to the sound section. ． If the number of distribution sections is large, it takes time to detect a failure section, and the power failure time from the power failure to the restoration becomes long.

[0007]. In order to prevent a power failure in a sound section, the automatic section switch after the faulty distribution section should be cut off before the breaker CB of the substation is cut off. At the time of a short circuit failure of 1, the automatic dividing switch may explode if a large current exceeding the breaking capacity of the automatic dividing switch is cut off. For this reason, conventionally, it was not possible to interrupt the automatic switchgear arranged on the distribution line prior to the circuit breaker CB of the substation at the time of both a short circuit failure and a ground fault.

The object of the present invention is to cut off the circuit breaker of the substation as before when a short-circuit fault occurs in the distribution section.
In the case of a ground fault, the automatic classification switch of the distribution section detects the ground fault by itself and shuts off before the circuit breaker of the substation, and the substation is uninterrupted, and after the distribution section of the ground fault. There is a power outage only, and there is no power outage in the healthy section on the substation side from the distribution section with a ground fault, which is to reduce the outage section and shorten the outage time.

[0009]

The automatic section switch according to claim 1 of the present invention is arranged at the section points of the distribution sections A ₁ , A ₂ ... Of the time-progressive type distribution line 1 as shown in FIG. The automatic distribution switch is installed and has a high-voltage switch S that can open and close the distribution line 1 for each of the distribution sections A ₁ , A _2, ..., By changing the opening delay time peculiar to this high-voltage switch M. It is set to be shorter than the operating time of the ground fault protection relay at the substation and longer than the operating time of the short-circuit protection relay of the sub-time limit characteristic of the substation.

According to a second aspect of the present invention, the automatic switchgear according to claim 2 is a zero-phase current transformer ZCT for selectively detecting a ground fault / short-circuit fault occurring in distribution sections A ₁ , A _2, ... Zero-phase transformer ZPD, ground-phase relay E that operates by receiving zero-phase current and zero-phase voltage from them, first relay G and second relay F that sequentially operate by the operation of ground-fault direction relay E. , A high-voltage switch M for opening and closing the substation side and the load side of the distribution line 1, a timer for setting the closing time specific to the automatic division switch and the detection time after the closing, and a power source for the load side during re-transmission. An automatic section switch H having a lock mechanism for locking so as not to be sent, and an opening delay circuit 3 for setting an opening delay time unique to the high voltage switch S, and the unique opening delay set by the opening delay circuit 3 Time to move substation ground fault protection relay It is obtained by setting longer than the operation time of the short-circuit protection relay of inverse time characteristics of time shorter than the substation.

In the automatic section switch according to claim 3 of the present invention, as shown in FIG. 1, the open delay circuit 3 includes a diode D ₁ and a resistor R, which are connected in parallel to the operating electromagnet m of the high voltage switch S. It consists of a series circuit.

In the automatic section switch of claim 4 of the present invention, as shown in FIG. 2, the distribution section A ₁ of the time-progressive type distribution line ₁ ,
Is installed to the section point of the A ₂ · · ·, Te, an automatic sectionalizing switch having an openable pressure switch S of the distribution line 1 for each distribution leg A _1, A ₂ · · ·, this The opening delay time peculiar to the high-voltage switch S is made longer than the operation time of the short-circuit protection relay of the sub-time delay characteristic of the substation during normal operation, and automatically shorter than the operation time of the ground fault protection relay of the substation at the time of a ground fault. It was made to become.

According to a fifth aspect of the present invention, the automatic section switch has a distribution section A ₁ of the time-sequential distribution line 1 as shown in FIG.
A ₂ zero-phase selecting detects ground-short-circuit fault occurring ... current transformer ZCT, the zero-phase transformer ZPD, zero-phase current from them, ground fault direction relay E which operates by receiving a zero-phase voltage, A first relay G, a second relay F, which sequentially operate by the operation of the ground fault direction relay E, a high-voltage switch S that opens and closes the substation side and the load side of the distribution line 1, and a unique automatic segment switch. An automatic delay switch H having a timer for setting a closing time and a detection time after the closing, a lock mechanism for locking the power supply to the load side during re-power transmission, and an opening delay time unique to the high voltage switch S are provided. A variable open delay circuit 4 for setting is provided, and the open delay time set by the variable open delay circuit 4 is set to be longer than the operation time of the short-circuit protection relay of the sub-interval characteristic of the substation of the substation during normal operation. In case of a ground fault, the substation ground Is obtained by shortening allows a to automatically shorter than the operating time of the protection relay.

According to a sixth aspect of the present invention, in the automatic section switch according to the fifth aspect of the present invention, the variable opening delay circuit 4 of the automatic section switch according to the fifth aspect has a diode in the operating electromagnet m of the high voltage switch S. D ₁ and the resistor R _1, a series circuit of R ₂ connected in parallel, the resistance R ₂ in the open contact g ₂ of the first relay G, g ₄ and connected in parallel during normal is the resistor R ₂ Is short-circuited, and the same resistance R ₂ causes the diode D
₁ and the resistor R ₁ so as to be inserted in series.

[0015]

According to the first aspect of the present invention, the automatic division switch has the opening delay time set shorter than the operation time of the ground fault protection relay of the substation. Make sure to break the circuit breaker in the substation before breaking it in case of failure. Therefore, there is no power outage in the substation, and only the power distribution section after the ground fault has a power failure, and no power failure occurs in the healthy section on the substation side from the power distribution section with the ground fault. Also, since the opening delay time is set longer than the operating time of the short-circuit protection relay of the sub-time characteristics of the substation, in the event of a short-circuit fault in the distribution section, the short-circuit protection relay of the substation is shut off and the automatic classification switch explodes. There is nothing to do.

[0016]

According to the second aspect of the invention, since the zero-phase current transformer ZCT and the zero-phase transformer ZPD are provided in the automatic section switch of the second aspect,
When a ground fault occurs in the distribution section, the fault causes the zero-phase current transformer Z.
Selected by CT and zero-phase transformer ZPD. That is,
The automatic division switch itself detects a ground fault in the distribution section. Further, the zero-phase current transformer ZCT, the zero-phase current from the zero-phase transformer ZPD, and the zero-phase voltage actuate the ground fault direction relay E, the first relay G, and the second relay F to operate the automatic section switch. Open and shut off. At this time, the open delay time by the open delay circuit 3 is the operating time of the ground fault protection relay of the substation (eg, 0.8
Since it is set to be shorter than (seconds) (eg, 0.6 seconds), the automatic section switch is always opened and closed before the breaker CB of the substation is closed. Therefore, there is no power outage in the substation, and only the power distribution section after the ground fault has a power failure, and no power failure occurs in the healthy section on the substation side from the power distribution section with the ground fault. Also, because the open delay time is set longer than the operating time of the short-circuit protection relay of the sub-time characteristics of the substation, in the event of a short-circuit fault in the distribution section, the short-circuit protection relay of the substation is shut off and the automatic classification switch explodes. There is nothing to do.

[0017]

According to the third aspect of the invention, in the automatic switchgear according to the third aspect of the invention, since the open delay circuit 3 is constituted by the series circuit of the diode D ₁ and the resistor R, the diode D ₁
By arbitrarily selecting the time constant of the resistance R and the resistance R, the open delay time can be set to an arbitrary time shorter than the operation time of the ground fault protection relay of the substation.

[0018]

According to a fourth aspect of the present invention, in the automatic switchgear according to the fourth aspect, the opening delay time is longer than the operation time of the short-circuit protection relay having the anti-time delay characteristic of the substation at normal times, and the ground fault of the substation at the time of ground fault. Since it is shortened to be shorter than the operating time of the protection relay, in the event of a short circuit failure, the automatic switchgear will always open after the circuit breaker of the substation is shut off, and a large short-circuit current will flow to the automatic switchgear. The division switch does not explode.
In addition, in the event of a ground fault, the circuit breaker of the substation always shuts off before it shuts down, the substation is uninterrupted, and only the distribution section after the ground fault has a power failure. There is no power outage in healthy sections.

[0019]

According to the fifth aspect of the invention, since the zero-phase current transformer ZCT and the zero-phase transformer ZPD are provided in the automatic division switch according to the fifth aspect,
When a ground fault occurs in the distribution section, it causes a zero-phase current transformer ZC.
It is selectively detected by the T, zero-phase transformer ZPD. That is, the automatic division switch itself detects a ground fault in the distribution section. Further, the zero-phase current transformer ZCT, the zero-phase current from the zero-phase transformer ZPD, and the zero-phase voltage actuate the ground fault direction relay E, the first relay G, and the second relay F to operate the automatic section switch. Open and shut off. At this time, the open delay time set by the variable open delay circuit 4 is longer than the operation time (eg, 0.2 seconds) of the short-circuit protection relay having the reverse time limit characteristic of the substation during normal operation (eg, 1. 0 seconds), in the event of a ground fault, it can be automatically shortened (eg, 0.6 seconds) to the operating time (eg, 0.8 seconds) of the ground fault protection relay in the substation, so a short circuit can occur. In the event of a failure, the automatic switchgear will always open after the circuit breaker at the substation shuts off, and a large short-circuit current will not flow through the automatic switchgear to prevent the automatic switchgear from exploding. Also, in the event of a ground fault, be sure to disconnect before the circuit breaker at the substation,
The substation is uninterrupted, and the power failure occurs only after the distribution section with the ground fault, and the healthy section on the substation side from the distribution section with the ground fault does not fail at all.

[0020]

According to the sixth aspect of the present invention, in the automatic switchgear according to the sixth aspect of the present invention, the open delay circuit 4 is formed by connecting the operating electromagnet m of the high-voltage switch S with the diode D ₁ and the resistors R ₁ and R ₂ in series. were connected in parallel, the opening contacts g _2, g ₄ of the resistance R ₂ in the first relay G connected in parallel, the normal state is the resistance R ₂ is short-circuited, the resistor R at the time of ground fault ₂ is the diode D _1, resistors for the R ₁ are then to be inserted in series, by arbitrarily selecting the time constant of the diode D ₁ and a resistor R _1, R _2, opening delay time any time Can be specified. Also, in this automatic switchgear, the open contacts g ₂ and g ₄ are normally closed and the resistor R ₂ is short-circuited, and the open delay time becomes long. However, when a ground fault occurs, the open contacts g ₂ and g ₄ are opened and the resistance is reduced. R ₂ is inserted, the series resistance becomes R ₁ + R ₂ , and the opening delay time is shortened. For example, the opening delay time in normal times can be set to 1.0 second, and the opening delay time at the time of a ground fault can be shortened to 0.6 seconds or less.

[0021]

First Embodiment FIG. 1 shows a first embodiment of the automatic division switch according to the present invention. This automatic sorting switch is composed of a high voltage switch S and a control box T.

The high-voltage switch S is provided with a zero-phase current transformer ZCT, a zero-phase transformer ZPD, a switch M, and an open delay circuit 3 consisting of a resistor R and a diode D ₁ . The opening delay circuit 3 sets the opening delay time of the automatic division switch. This opening delay time is the time until the high-voltage switch of the automatic division switch opens without voltage. Normally, the opening delay time in the case of a ground fault is 0.6 seconds and the opening delay time in the case of a short circuit is 0.4.
Seconds.

The control box T includes operations of a zero-phase current transformer ZCT, a zero-phase current from the zero-phase transformer ZPD, a ground fault direction relay (DGR) E which operates by receiving a zero-phase voltage, and a ground fault direction relay E. There is provided a first relay G operated by the above, a second relay F opened when the first relay G operates, and an automatic section switch H. The automatic section switch H includes a timer for setting a closing time, a detection time for detecting a ground fault and a short circuit, and a relay device having a lock mechanism. Here, the turning-on time is the time until the switch M is turned on and the distribution lines on the substation side and the load side are connected after pressurizing the AC100V operation power supply in FIG. 1, that is, the automatic section switch. Is the time it takes to put the power into the distribution line, and is normally set to 7 seconds. In the case of an automatic switchgear installed on the branch line of the distribution line as shown in Fig. 3, it is set to 7 ns. The detection time is a time for detecting a ground fault or a short circuit after the closing, and is normally set to 6 seconds after the closing time (7 seconds).

In FIG. 1, e ₁ is an operating contact of the ground fault direction relay E, g ₂ and g ₄ are open contacts of the first relay G, and f is a second contact.
Of the relay F, T is a transformer for operating power supply.

The operation of the automatic division switch shown in FIG. 1 is performed when the distribution section is normal (no ground fault or short circuit fault), ground fault, ground fault disappears, short circuit fault, ground fault / short circuit fault. Each of the simultaneous occurrences will be described.

[0026]

[Normal operation] In FIG. 1, when the operating power AC100V is applied to the automatic section switch, the second contact F ₄ of the first relay G is closed so that the second relay F operates. The operating contact f _{1 of} F is closed. After that, the automatic classification switchgear H is activated → the open contact g ₂ of the first relay G
Closing circuit, switch M is closed after the preset time (eg, 7 seconds) set by the timer of automatic classification switchgear H → Automatic classification switchgear H is mechanically locked (During reclosing, power is not transmitted to the load side. Hold) → Ground fault detected within the preset detection time (6 seconds) of the same timer → Ground fault not detected (no ground fault) → Automatic classification switchgear H unlocked (load (Power is transmitted to the side) → Normal (normal) operation is performed.

[0027]

[Operation in case of ground fault] When a ground fault occurs in the load side section of the high voltage switch shown in Fig. 1 during power transmission, the fault is detected by the zero-phase current transformer ZCT and the zero-phase transformer ZPD and Upon receiving the zero-phase current and the zero-phase voltage from the phase current transformer ZCT and the zero-phase transformer ZPD, the ground fault direction relay E operates, and thereafter, its operating contact e ₁ closed circuit → the first relay G operates. Open contact g
₂ , g ₄ open → The second relay F returns, its operating contact f ₁
Opening → The automatic sorting switch H is restored (stops operation). At this time, due to the opening of the open contact g _2, the high-voltage switch operates and the operating time of the ground fault protection relay at the substation (eg, 0.8
Second), the circuit is opened and shut off after a shorter opening delay time (eg, 0.6 seconds). Therefore, the circuit breaker (CB) at the substation will not be cut off,
There is no power outage in the healthy section on the substation side from the ground fault section.

When there is no voltage after the ground fault failure section due to the opening and closing of the high-voltage switch, the ground fault current disappears, and thereafter, the ground fault direction relay E recovers, its operating contact e ₁ opens, and the first contact opens. relay -G is restored, the release contact g _2, g ₄ closed → second relay F operation, the high pressure switch is turned on its operation contact f is after closing → automatic sectionalizing switch device H is activated → on time (7 seconds) (Reclosed) → Mechanical automatic switchgear H is mechanically locked → Ground fault current flows within the detection time → Ground fault direction relay E
, Its operating contact e ₁ closed circuit → the first relay G operates, its open contacts g ₂ , g ₄ open → the second relay F returns, its operating contact f open → the automatic section switch H has no voltage And mechanically remains locked in the shut-off state. As a result, the high-voltage switch is opened after the opening delay time (eg, 0.6 seconds), and the failure section is disconnected (not re-closed). That is, the circuit breaker (CB) of the substation is not cut off, and the state in which there is no power failure is maintained in the healthy section on the substation side from the ground fault section.

[0029]

[Operation during short-circuit failure] If a short-circuit failure occurs during power transmission →
Ground fault direction relay E in Fig. 1 is inoperative, its operating contact e _{1 is} open → Short circuit protection relay with sub-time characteristics of the substation is operating → Substation circuit breaker (CB) after operating time (eg 0.2 seconds) ) Is cut off → no voltage → automatic switchgear H is restored, operating contact f is opened → high voltage switch is opened after an opening delay time (eg 0.4 seconds), and the short circuit fault section is cut off by reclosing the substation. To be done.

[0030]

[Operation when ground fault and short-circuit fault occur simultaneously] When a ground fault and a short-circuit fault occur at the same time during power transmission → The ground fault direction relay E in Fig. 1 operates, its operating contact e ₁ closed circuit → the first relay G Operation, the open contacts g ₂ and g _{4 are} opened. At the same time, the short-circuit protection relay (reverse time characteristic) of the substation operates → the breaker of the substation shuts off after the operating time (eg, 0.2 seconds) → no voltage → the ground fault direction relay E recovers and operates Opening of contact e ₁ → the first relay G is restored, and the open contacts g ₂ and g _{4 are} closed. Also, due to the non-voltage, the automatic section switch H
Returns, its operating contact f opens → open delay time (eg, 0.
After 4 seconds), the high voltage switch was opened and the short circuit and the ground fault section were cut off due to the reclosing of the substation.

[0031]

[Embodiment 2] FIG. 2 shows a second embodiment of the automatic division switch according to the present invention. The structure of this automatic division switch is basically the same as that of the automatic division switch of the first embodiment of FIG.
The difference is, as are clearly in Figure 2, the open contact of the first relay G by one more than the case of FIG. 1 g _2, g
₄ and g ₆ , and the operating electromagnet m in FIG.
Is connected in parallel with a series circuit of a diode D ₁ and resistors R ₁ and R ₂ , and the open contact g of the first relay G is connected to the resistor R ₂ .
_2, g ₄ and connected in parallel, the normal state is the resistance R ₂ are short-circuited, at the time of ground fault the the same resistance R ₂ diode D
₁ , the resistor R ₁ is inserted in series.

The operation of the automatic division switch shown in FIG. 2 is performed when the distribution section is normal (no ground fault or short-circuit fault), ground fault, ground fault disappears, short-circuit fault, ground fault / short-circuit fault. Each of the simultaneous occurrences will be described.

[0033]

[Normal operation] In FIG. 2, when the operating power AC100V is applied to the automatic switching device, the open contact g ₆ of the first relay G is closed and the second relay F is operated. ₁ closes. After that, the automatic partition switch H starts up → the opening contact g ₄ of the first relay G is closed so that the switch M is closed after the closing time → the automatic partition switch H is mechanically locked → within the detection time after closing The ground fault is detected, the ground fault is not detected, the automatic section switch H is unlocked, and the normal operation is performed.

[0034]

[Operation in case of ground fault] When a ground fault occurs in the load side section of the high-voltage switch shown in Fig. 2 during power transmission, it causes a zero-phase current transformer Z.
CT, zero-phase current transformer Z detected by zero-phase transformer ZPD
Upon receiving CT, the zero-phase current and the zero-phase voltage from the zero-phase transformer ZPD, the ground fault direction relay E operates and its operating contact e ₁ is closed. After that, the first relay G operates and its open contact g
₂ , g ₄ , g ₆ open → the second relay F returns, its operating contact f ₁ open → the automatic section switch H returns. At this time, since the open contacts g ₂ and g ₄ are opened as described above, the high-voltage switch has an open delay time (example 0.8 seconds) shorter than the operating time (example 0.8 seconds) of the ground fault protection relay in the substation.・ 0.6
After 2 seconds) open and shut off. Therefore, the circuit breaker of the substation is not cut off, and the healthy section on the substation side of the ground fault section does not fail at all.

When there is no voltage after the ground fault section due to the above-mentioned high voltage switch opening and shutting off, the ground fault current disappears, the ground fault direction relay E recovers, and its operating contact e ₁ opens.
Pressure relay -G is restored, the release contact g _2, g _4, g ₆ closed → second relay F operation, after the operation contact f closing → automatic sectionalizing switch device H is activated → on time (7 seconds) Switch S closed (re-closed) → mechanical automatic switchgear H mechanically locked → ground fault current flows within detection time (6 seconds) → ground fault direction relay E operates, its contact e ₁ closed → 1 relay G is operated, and a release contact g _2, g _4, g ₆ open → second relay F is restored, the operation contact f open → automatic sectionalizing switch device H for mechanically blocking state becomes no voltage It remains locked. At this time, since the open contacts g ₂ and g ₄ are open as described above, the high-voltage switch S has an open delay time (eg,
After 0.6 seconds), the opening section → the failure section is separated (do not re-input). That is, the circuit breaker (CB) of the substation is not cut off, and the state in which there is no power failure in the healthy section on the substation side of the ground fault section is maintained.

[0036]

[Operation during short-circuit failure] If a short-circuit failure occurs during power transmission →
Ground fault direction relay E is not operating, its operating contact e _{1 is} open → Short circuit protection relay operation of substation time limit characteristics → Breaker (CB) interruption at substation after operation time (eg 0.2 seconds) → None Voltage → Automatic division switch H is restored, operating contact f is opened → High voltage switch S is opened after opening delay time (eg, 1.0 seconds),
The short circuit fault section is cut off due to the reclosing of the substation.

[0037]

[Operation when ground fault and short-circuit fault occur simultaneously] When a ground fault and a short-circuit fault occur at the same time during power transmission → ground fault direction relay E operation in Fig. 2, its operating contact e ₁ closed circuit → first relay G operation,
Its opening contacts g _2, g _4, the g ₆ open. At the same time, the operation of the short-circuit protection relay in the substation → operating time (eg 0.2
After a second), the circuit breaker of the substation is shut off → no voltage → ground fault direction relay E is restored, its operating contact e _{1 is} opened → first relay G is restored,
Its opening contacts g _2, g _4, g ₆ becomes closed. Also, due to the above-mentioned no voltage, the automatic switching device H is restored, the operating contact f is opened, and the high voltage switch is opened after an opening delay time T (eg, 1.0 seconds), and a short circuit occurs due to the reclosing of the substation. And the ground fault fault section is cut off.

[0038]

[Embodiment 3] A current transformer (CT) and an overcurrent relay are added to the automatic division switch shown in FIGS. 1 and 2, and the first relay G operates only when the load current is below a set value. By doing so, an automatic partition switch having characteristics similar to those of the automatic partition switch of FIGS. 1 and 2 can be obtained.

[0039]

[Example of use] Next, an example of use of the automatic division switch of the present invention will be described. The automatic section switch of the present invention is arranged at a section point of the time-sequential type distribution line 1 as shown in FIG. 3, for example. In FIG. 3, the automatic division switch of the present invention is indicated by a double circle, and the conventional automatic division switch is indicated by a single circle.

As shown in FIG. 3, when two automatic division switches B ₁ and B ₂ are installed in a series distribution section of the same distribution line,
The opening delay time of the load side automatic switchgear is shorter than that installed at the substation side (for example, about 0.2 seconds), and when a ground fault occurs, the load side automatic switchgear switch is It is recommended that the automatic section switch on the local side be shut off and opened prior to the automatic switch, so that the power failure section (power failure area) can be made as narrow as possible.

The turn-on times of the automatic section switches B ₁ and B ₂ arranged in the series distribution section of the same distribution line in FIG. 3 and the automatic section switches B ₄ arranged after the second branch line are Although each is 7 seconds, the closing time of the automatic section switch B ₃ arranged at the first position of the branch line is 7 n seconds (for example, 14 seconds), and power is first transmitted to the series distribution section, and then the branch line. Power is transmitted to the power distribution section.

[0042]

[Ground fault] When a ground fault occurs in the distribution section A ₃ in Fig. 3, a ground fault current flows in the direction of the arrow in Fig. 3 and the ground fault direction relays of the automatic switchgear B ₁ , B ₂ are activated. Although it operates, the opening delay time of the automatic partition switch B ₂ is shorter than the opening delay time of the automatic partition switch B ₁ by 0.2 seconds, so the automatic partition switch B ₁ does not open and the automatic partition switch B ₁ does not open. Only B ₂ is open. Also, since the operating time (eg 0.8 seconds) of the ground fault protection relay in the substation is longer than the opening delay time of the automatic section switches B ₁ , B _2, ..., The circuit breaker CB in the substation is not cut off either. . When the ground fault is in the power distribution section A ₁ , the circuit breaker CB of the substation operates to cut off.

[0043]

[When the ground fault has been resolved] At this time, the automatic section switch B _{2 of} FIG. 3 is activated and is reclosed after the closing time (7 seconds) (at this time, the automatic section switch H is mechanically locked. The next distribution section (distribution section A in which the ground fault has been resolved)
_{When the} power is transmitted to ₃ ), the ground fault is not detected during the detection time (6 seconds), and then the automatic section switch H is unlocked and returns to the normal state.

[0044]

[When the ground fault continues] At this time, the automatic section switch B ₂ in FIG. 3 is activated and is reclosed after the closing time (7 seconds) (at this time, the automatic section switch H is mechanically locked. When the power is transmitted to the next distribution section (distribution section A ₃ where the ground fault continues), the ground fault direction relay of the automatic classification switch B ₂ operates within the detection time (6 seconds). , The automatic section switch B ₂ is opened and shut off after the opening delay time,
The automatic section opening / closing device H remains mechanically locked so that the ground fault section A ₃ is separated and is not re-input.

[0045]

According to the automatic switchgear of claim 1, in the event of a ground fault, the automatic switchgear always shuts down before the breaker of the substation shuts down. There is no power outage in the healthy section on the substation side from the distribution section with a ground fault, and the failure section is opened and shut off after the opening delay time. Further, in the event of a short circuit failure, the circuit breaker of the substation shuts off before the automatic classification switch, so that a short circuit current (large current) does not flow to the automatic classification switch and the automatic classification switch does not explode.

[0046]

[Effect of the invention of claim 2]. In the automatic section switch according to claim 2, the zero-phase current transformer ZCT,
Since the zero-phase transformer ZPD is provided, it is possible to detect a short circuit fault or a ground fault in the automatic division switch itself. ． There is no power outage in the substation because the automatic division switch opens and shuts off before the circuit breaker (CB) in the substation shuts off.
There is no power outage in the healthy section on the substation side from the distribution section with a ground fault. ． The open delay circuit 3 can arbitrarily select the open delay time T.

[0047]

According to the third aspect of the present invention, in the automatic switchgear according to the third aspect, the open delay time is determined from the operation time of the ground fault protection relay of the substation by arbitrarily selecting the time constant of the diode D ₁ and the resistor R. Can be selected at any short time.

[0048]

According to the automatic switchgear of claim 4, since the opening delay time is automatically shortened in the case of a ground fault than in normal times, the circuit breaker of the substation is shut off during normal times. The circuit breaker can be opened before the circuit breaker in the substation is broken in the event of a ground fault. Therefore, as in the case of claim 1, a short-circuit current does not flow through the automatic division switch to explode the automatic division switch when a short-circuit failure occurs,
In the event of a ground fault, the substation will be uninterrupted, and the healthy section on the substation side of the distribution section with the ground fault will not have any power failure.

[0049]

According to the fifth aspect of the invention, the automatic division switch of the fifth aspect can detect a short-circuit fault and a ground fault by the automatic division switch itself as in the case of the second aspect. The substation is uninterruptible, and the healthy section on the substation side from the distribution section with the ground fault does not fail at all, and the open delay time can be arbitrarily selected.

[0050]

According to the sixth aspect of the invention, since the opening delay time of the automatic switchgear according to the sixth aspect is shortened during a ground fault rather than under normal conditions, a short circuit protection relay having an anti-time limit characteristic of a substation is the first in the event of a short circuit failure. In the event of a ground fault, the automatic classification switch will shut off before the substation ground fault protection relay. For this reason,
The automatic division switch does not explode when there is a short-circuit failure, there is no power outage in the substation when there is a ground fault, and there is no power outage in the healthy section on the substation side from the distribution section with a ground fault.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a first embodiment of an automatic division switch according to the present invention.

FIG. 2 is an explanatory view showing a second embodiment of the automatic division switch according to the present invention.

FIG. 3 is an explanatory view showing an example of arrangement of the automatic division switch of the present invention on a time-sequential progressive power distribution line.

FIG. 4 is an explanatory diagram of a conventional time-sequential progressive distribution line.

[Explanation of symbols]

1 is a time-progressive type distribution line 3 is an open delay circuit 4 is a variable open delay circuit A ₁ , A ₂ is a distribution section B ₁ , B ₂ is an automatic switchgear ZCT is a zero-phase current transformer ZPD is a zero-phase transformer Switch S is a high voltage switch E is a ground direction relay G is a first relay F is a second relay M is a switch H is an automatic switchgear D ₁ is a diode R, R ₁ and R ₂ is a resistor m is activated electromagnet

[Procedure amendment]

[Submission date] August 12, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction content]

[0016]

According to the second aspect of the invention, since the zero-phase current transformer ZCT and the zero-phase transformer ZPD are provided in the automatic section switch of the second aspect,
When a ground fault occurs in the distribution section, the fault causes the zero-phase current transformer Z.
Selected by CT and zero-phase transformer ZPD. That is,
The automatic division switch itself detects a ground fault in the distribution section. Further, the zero-phase current transformer ZCT, the zero-phase current from the zero-phase transformer ZPD, and the zero-phase voltage actuate the ground fault direction relay E, the first relay G, and the second relay F to operate the automatic section switch. Open and shut off. At this time, the open delay time by the open delay circuit 3 is the operating time of the ground fault protection relay of the substation (eg, 0.8
Since it is set to be shorter than (seconds) (eg, 0.6 seconds), the automatic section switch is always opened and closed before the breaker CB of the substation is closed. Therefore, there is no power outage in the substation, and only the power distribution section after the ground fault has a power failure, and no power failure occurs in the healthy section on the substation side from the power distribution section with the ground fault . Also since the operation time <br/> by Ri rather long setting of the short-circuit protection relay of inverse time characteristics of substation the open delay time, short-circuit protection relay of the substation during a short circuit failure of the distribution leg is cut off earlier The automatic sorting switch will not explode.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

The high-voltage switch S is provided with a zero-phase current transformer ZCT, a zero-phase transformer ZPD, a switch M, an open delay circuit 3 consisting of a resistor R and a diode D ₁ . The opening delay circuit 3 sets the opening delay time of the automatic division switch. This opening delay time is the time until the high-voltage switch of the automatic division switch opens without voltage. Normally, the opening delay time is 0.6 seconds when a ground fault occurs, and the opening delay time is 0. 6
Seconds.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

[0029]

[Operation during short-circuit failure] If a short-circuit failure occurs during power transmission →
Ground fault direction relay E in Fig. 1 is not operating, its operating contact e _{1 is} open → Short-circuit protection relay of reverse time characteristic of substation is operating → Substation circuit breaker (CB) after operating time (eg 0.2 seconds) ) is cut off → No voltage → automatic sectionalizing switch device H is restored, operation contacts f open → becomes a high pressure switch opens after opening delay time (eg, 0.6 seconds), release cut short circuit fault section by reclosing the substation To be done.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

[0030]

[Operation when ground fault and short-circuit fault occur at the same time] When a ground fault and a short-circuit fault occur at the same time during power transmission → The ground fault direction relay E in Fig. 1 operates, its operating contact e ₁ closed circuit → the first relay G Operation, the open contacts g ₂ and g _{4 are} opened. At the same time, the short-circuit protection relay (reverse time characteristic) of the substation operates → the breaker of the substation shuts off after the operating time (eg, 0.2 seconds) → no voltage → the ground fault direction relay E recovers and operates The contact e _{1 is} opened → the first relay G is restored, and the open contacts g ₂ and g _{4 are} closed. Also, due to the non-voltage, the automatic section switch H
Returns, its operating contact f opens → open delay time (eg, 0.
After 6 seconds), the high voltage switch was opened, and the ground fault and the ground fault section were cut off due to the reclosing of the substation.

Claims (6)

[Claims] 1. A power distribution section (A) of a timed progressive power distribution line (1).
_1, automated which is installed to the section point of the A ₂ · · ·), with the same distribution line (1) the distribution leg (A _1, A ₂ · · ·) openable pressure switch for each (S) It is a segmented switch, and the opening delay time peculiar to this high-voltage switch (S) is set to be shorter than the operating time of the ground fault protection relay of the substation and longer than the operating time of the short-circuit protection relay of the sub-time limit characteristic of the substation. Characteristic automatic classification switch. 2. A power distribution section (A) of a time-sequential progressive power distribution line (1).
₁ , A ₂ ...) Zero-phase current transformer (ZCT) and zero-phase transformer (ZPD) that selectively detect ground faults and short-circuit faults, and operate by receiving zero-phase current and zero-phase voltage from them. A ground fault direction relay (E), a first relay (G), a second relay (F) that sequentially operate by the operation of the ground fault direction relay (E), and a substation side of the distribution line (1). A high-voltage switch (S) that opens and closes the load side, a timer that sets the closing time unique to the automatic classification switch and the detection time after the closing, and a lock that locks the power supply to the load side during power re-transmission. An automatic division switchgear (H) having a mechanism, an open delay circuit (3) for setting an open delay time specific to the high voltage switch (S), and the specific open delay set by this open delay circuit (3) Make the time shorter than the operating time of the ground fault protection relay of the substation An automatic switchgear that is set to be longer than the operating time of the short-circuit protection relay with time characteristics. 3. The open delay circuit (3) comprises a series circuit of a diode (D ₁ ) and a resistor (R) connected in parallel with an operating electromagnet (m) of the high-voltage switch (S). The automatic sorting switch according to claim 2. 4. A power distribution section (A) of a time-sequential type distribution line (1).
₁ , A ₂ ...) installed at the dividing points, and the automatic distribution switching with the high-voltage switch (S) that can open and close the distribution line 1 for each distribution section (A ₁ , A ₂ ...) The open delay time peculiar to this high-voltage switch (S) is made longer than the operation time of the short-circuit protection relay of the sub-time delay characteristic of the substation during normal operation, and the earth delay protection relay of the substation at the time of ground fault failure. An automatic switchgear that is designed to automatically shorten the operating time. 5. A power distribution section (A of the time-sequential progressive power distribution line (1).
₁ , A ₂ ...) Zero-phase current transformer (ZCT) and zero-phase transformer (ZPD) that selectively detect ground faults and short-circuit faults, and operate by receiving zero-phase current and zero-phase voltage from them. A ground fault direction relay (E), a first relay (G), a second relay (F) that sequentially operate according to the operation of the ground fault direction relay (E), and a substation side of the distribution line (1). A high-voltage switch (S) that opens and closes the load side, a timer that sets the closing time unique to the automatic classification switch and the detection time after the closing, and a lock that locks the power supply to the load side during power re-transmission. An automatic section switchgear (H) having a mechanism, a variable opening delay circuit (4) for setting an opening delay time unique to the high voltage switch (S), and the opening set by the variable opening delay circuit (4) Delay time, short-circuit protection of the substation's anti-time delay characteristics during normal operation An automatic switchgear that is longer than the relay operation time and can be shortened automatically to be shorter than the operation time of the ground fault protection relay in the substation in the event of a ground fault. 6. The variable open delay circuit (4) comprises a diode (D) on an operating electromagnet (m) of the high voltage switch (S).
₁ ) and resistors (R ₁ , R ₂ ) connected in parallel,
The open contact (g ₂ , g ₄ ) of the first relay (G) is connected in parallel to the resistance (R ₂ ) and the resistance (R _2
2) are short-circuited, the resistance at the time of ground fault (R ₂₎ is the diode (D _1), the resistance (R ₁₎ in claim 5, wherein the composed configured to be inserted in series Automatic sorting switch.