JPH0618449B2 - GIS equipment protection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Use of the Invention The present invention is configured so that each electric device such as a shutter and a disconnector is housed in a gas chamber in which an insulating gas is pressure-sealed.
Related to the protection method of IS equipment, especially for protecting the break or breaker even if it is inserted in series to the transmission line to the other end substation or even if the gas pressure in the gas chamber of the breaker falls GIS
It relates to a method of protecting equipment.

[Background of the Invention]

Fig. 1 shows the configuration of an example of a normal GIS (Gas Insulated Swichgear) equipment. According to this, the GIS equipment includes bus bars 4, 4A and transmission lines 5, 25 going out.
In addition, the transformer 11 is installed in the substation premises. Each feeder has disconnectors 3, 13, 13A, 23, shiya disconnectors 2, 12,
12A and 22 and line switches 1 and 21 are provided as shown. Generally, these electric devices are individually equipped with gas chambers 6, 7, 8, 17, 17A, 1
It is usually housed in 8, 18A, 26, 27, 28, 9 separately from the others. Insulation is enhanced by pressure-sealing an insulating gas such as SF ₆ gas in each gas chamber.
In addition, a gas pressure gauge (not shown) for detecting a decrease in gas pressure is installed. Reference numeral 16 in FIG. 1 indicates an oil insulating chamber.

FIG. 2 shows a control logic for mutual interlock when the gas pressure in the gas chamber shown in FIG. 1 is lowered. In FIG. 1, for example, gas chambers 8, 9, 1
When the gas pressure drops in any of 8 and 28,
It is necessary to disconnect all feeders, breakers 2, 12, 22 and the like connected to the bus bar 4 and adopt an interlock so that no voltage is applied to the bus bar 4.
For this reason, in FIG. 2, the gas chambers 8, 9, 18, 2 are
Gas pressure drop detection signals 8 (L), 9 (L), 18
(L) and 28 (L) are logically ORed by the air circuit 32 and then input to the OR circuits 33 to 35. As a result, if the gas pressure drops in any of the gas chambers 8, 9, 18, 28, the breakers 2, 12, 22 are tripped. Further, for example, when the gas pressure in the gas chamber 7 drops, the following measures are taken.

That is, if the disconnecting switch 3 and the line switch 1 are open, the voltage is not applied to the sushi and the sever 2 so that the sushi and the severing devices 12 and 22 and the other end and the severing device which are adjacently connected are connected. It is not necessary to take the interlock with (the partner's substation or the breaker (not shown)). However, when the disconnector 3 is in the closed state, the contactor 2 is connected to the bus bar 4, and accordingly, the disconnectors 13, 23 and the contactors 12, 22 are closed. Assuming that the breakers 12 and 22 connected to the bus bar 4 are all tripped interlocks. When the line switch 1 is closed, the PLC (Power Line C
It is necessary to use an interlock that gives a trip command to the other end's end or a breaker by using an arrier). Therefore, in FIG. 2, the gas pressure drop detection signal 7 in the gas chamber 7 is detected.
(L) is the OR circuit 3 via the 1-input NOT AND circuit 37
It is input to 4,35. When the open signal 3 (O) of the disconnector 3 is not obtained, the OR circuits 34, 35
Is used to trip the switches 12 and 22. When the open signal 1 (O) of the line switch 1 is not obtained, the gas pressure drop detection signal 7 ((L) is output from the OR circuit 36 via the 1-input negative AND circuit 38,
As a result, the other end and the breaker are tripped. When the gas pressure in the gas chamber 6 further decreases, the transmission line 5 is irrespective of whether the line switch 1 is opened or closed.
While the other end of the other end and the breaker are given a trip command using signal transmission means such as PLC to be tripped, at the same time, the self end and the breaker 2 are also tripped. It As shown in FIG. 2, the gas pressure drop signal 6 (L) of the gas chamber 6 is directly input to the OR circuits 33 and 36, and the breaker 2 and the other end or breaker are tripped at the same time. It is a thing.

The above is for a specific gas chamber, but other gas chambers 17, 17A, 18, 1A, 26, 27, 28, 9
Although not shown in the drawing, the same mutual interlock is adopted for the decrease in gas pressure.

FIG. 3 shows a remote trip by a mutual interlock in the case where the gas pressure in the gas chamber 7 decreases or the gas pressure in the gas chamber 6 decreases with the line switch 1 in FIG. 1 closed. It shows the control system of the other end and disconnecting trip).

As already described in FIG. 1 and FIG. 2, when the decrease in gas pressure is detected, the remote trip command 38R is output. This trip command 38R is transmitted to the power transmission line 5 by the transmitter 51 in PLC equipment or the like. It is supposed to be superposed or transmitted to the other end side by another signal transmission path. On the other hand, in the PLC equipment or the like at the other end substation, the receiving device 52 receives this, and the other end or disconnector 47 is tripped by the trip command 58 from the receiving device 52. Incidentally, in FIG. 3, the remote trip command 38A, the transmitter 51A and the receiver 52A,
Further, the remote trip command 58A to the chopsticks and electric appliance 2 is a trip control system in the case where the GIS equipment at the partner substation has an accident contrary to the above description. Also, reference numeral 4
Reference numerals 6, 48 and 49 denote line switches, disconnectors and bus bars at the other end substation.

Here, the transmitter 51 will be described. When the trip signal 38R is inputted in pulses to the set terminal of the flip-flop 61 as shown in FIG. 4, the set output (Q) thereof is in the so-called "1" state. This set output is superimposed on the power transmission line 5 via the transmitter 62 (in the case of using PLC), and is transmitted to the other end as a trip signal of the disconnector 47. In this case, it is clear that the set output of flip-flop 61 will remain in the "1" state until a reset signal is input to its reset terminal.

On the other hand, in the receiving device 52 at the other end substation, the trip signal is received by the receiver 71 as can be seen from FIG. 5, but the received trip signal is sent by the monostable multivibrator 72 to a pulse-shaped trip command. After being converted into 58, it is given to the brush 47 and the breaker 47.
As a result, the breaker 47 is tripped, but the reception trip signal from the receiver 71 is also input to the one-input negating AND circuit 73 for closing command. Therefore, as long as the reception trip signal maintains the "1" state, even if the closing command 74 is input to the AND circuit 73, the closing command is blocked here. That is, for example, it is possible to completely prevent the breaker 47 from being accidentally turned on before the gas pressure in the gas chamber 7 is restored. This is because when the gas pressure in the gas chamber 7 returns to normal, the flip-flop 61 is reset by a reset command from the gas pressure gauge only after the normal gas pressure is confirmed.

When the flip-flop 61 is reset, the transmission of the trip signal is stopped, so that the reception trip signal from the receiver 71 is also lost and the closing command AND circuit 73 is opened to close the breaking switch 47. Signal 7
The lock of 4 is released.

In this way, when a gas pressure drop in the gas chamber is detected, the electric equipment in the gas chamber is completely disconnected from the system, and the entire substation is partially stopped or, in the worst case, completely stopped. However, in the state where the gas pressure drop is slight (about 1 atm) and before it reaches the worst, the load current cannot be cut off or cut off by the breaker or breaker in the gas chamber, but necessary insulation can be maintained. There is a case. In such cases,
It is possible to prevent a total stoppage of the entire substation as much as possible by tripping the load or the load current by first tripping the opposing mating end or breaker to cut off the load current. ing.

FIG. 6 shows a trip control system capable of performing such a function, and FIG. 7 shows a time chart for explaining the operation. In FIG. 6, the same reference numerals as those in FIG. 3 denote the same or equivalent parts.

In this example, assuming that the load current I ₅ is flowing through the power transmission line 5 as shown in FIG. 7, in response to a slight decrease in the gas pressure in the gas chamber 7, the explanation is given with reference to FIG. As in the case, the remote trip command 38R is output. The trip command 38R is converted into a continuous signal by the transmitter 51 and then transmitted to the other end side via the transmission path. At the other end, the receiving device 52 causes the pulse-shaped trip command 5 based on the trip command 38R.
8 is created, which causes the breaker 47 to be tripped at time t ₁ in FIG. 7. In this way, the current I ₅ flowing through the transmission current 5 becomes zero after the time point t ₂ which is the zero cross point by the tripping of the breaker 47. Therefore, when the timer 59 is set to time-up after this time t ₂ and the output 60 of the timer 59 trips the self-end side of the breaker or the breaker 2, the breaker 2 breaks the current. There is no need to worry that it will be damaged. Instead of the open-loop timer determination for the determination of the time point when the current I ₅ flowing through the transmission line 5 becomes zero, the current I ₅ after the trip of the circuit breaker 47 is determined.
_{If 5} is directly detected and it becomes zero, the breaker 2
It is also possible to perform closed-loop control so as to trip. In addition, the control in the case where the gas pressure drop described above is slight is performed when the gas pressure in the gas chamber 17 in the transformer 11 on the primary side or the disconnector 12 is reduced. It is applicable to tripping.

In any of the above cases, it is possible to damage the equipment due to mistaken insertion of the trap or breaker by prohibiting re-closing of the trap and breaker while the low gas pressure detection signal continues. It is possible to prevent such.

By the way, for example, when both the disconnector 3 and the line switch 1 are in the closed state, the other end or the breaker 47 is tripped due to the decrease in the gas pressure in the gas chamber 7.
Assuming that the tripping is tripped, the breaker 2 is placed in a charged state via the disconnector 3 to cause a problem. If the breaker 2 is in a charged state, the gas chamber 7 is continuously exposed to the breakage generated in the power system via the disconnector 3 and the switching surge of the breaker.
Depending on the gas pressure state, if the surge voltage or the breaker 2 becomes more seriously damaged, there is a danger. Further, since the closed state of the line switch 1 is continued as it is, the gas chamber 7 remains connected to the power transmission line 5 through the line switch 1, and surge voltage due to lightning generated on the power transmission line 5 is generated. It is said to be in danger. If the transmission line 5 tatami is to be hit by lightning or the like, the breaker 2 will be seriously damaged.

[Object of the Invention]

Therefore, an object of the present invention is to provide a GIS equipment capable of protecting a breaker or a circuit breaker even if the gas pressure drops in the gas chamber of the breaker that is inserted in series in the transmission line to the other end substation. To provide the protection method.

[Outline of Invention]

To this end, the present invention provides busbars each housed in an insulating gas chamber, a disconnector connected to the busbar, a sushi breaker connected to the disconnector and a sushi breaker connected to the disconnector. When the substation including the line switch is connected to the other end substation via the transmission line, the disconnector and the line switch are in the closed state, and the gas pressure in the gas chamber containing the breaker is If the load current cannot be cut off or cut off, but a gas pressure drop within the range that can maintain the required insulation is detected,
At the other end substation, after tripping the above-mentioned breaker or breaker-corresponding breaker or breaker, trip the breaker or breaker related to the above gas pressure drop, and then place it adjacent to the breaker or breaker. The disconnecting switch and the line switch are kept open.

Example of Invention

 The present invention will be described below with reference to FIG.

FIG. 8 shows a control logic and a control system which are assumed to exist between the bus bar and the power transmission line and to cause a gas pressure drop in the gas chamber containing the disconnector. As shown, this control logic differs from that shown in FIG. 2 in that the timers 79 and 80 and the AND circuits 81 and 82 are used to implement the present invention.
Is newly established.

No particular description is necessary for the same parts as those shown in FIG. 2, but if a slight decrease in gas pressure occurs in the gas chamber 7,
This fact is made remarkable by the AND circuit 81. In this case, the low gas pressure detection signal 7 (L) is not obtained, and therefore the ridges and the breakers 12 and 22 are prevented from being tripped. It is detected by the AND circuit 81 that the disconnector 3 is in the closed state, and that the gas pressure small drop detection signal 7 (L-1) is obtained, but continuously for a certain period of time. When the gas pressure small drop detection signal 7 (L-1) is obtained, the time-up output of the timer 79 is obtained as the trip command 38R via the OR circuit 36, so that the other end or the breaker 47 is released. It is a trip. If a certain time has elapsed after the shredder / breaker 47 was tripped, the timer 80 times out, and the shredder / breaker 2 is next tripped. Further, the breaker 2 is tripped and the gas pressure drop detection signal 7
The fact that (L-1) has been obtained is detected by the AND circuit 82, but this detection output is made and the disconnecting switch 3 and the line switch 1 are opened in the state where no current is flowing. It will be.

The control when the gas pressure in the gas chamber 7 slightly decreases has been described above. Incidentally, here, for example, the case where the gas pressure decreases in the other gas chambers 6, 8 and 17 regardless of whether the gas pressure is small or not will be described. And the breakers 2, 47 were tripped,
For the gas chamber 8, the chopsticks, breakers 2, 12, 22 and the like are tripped, and for the gas chamber 17, the chopsticks and breaker 12A are tripped first, and then the chopsticks and the breaker 12 are successively inserted. After that, the disconnector 13 is further opened. Not only in the gas chamber 7, but in the above-mentioned case, in general, in the case where a predetermined stroke or a breaker is tripped according to the gas chamber related to the gas pressure decrease, the power supply stop range is minimized. The electrical equipment housed in the gas chamber can be protected while being suppressed.

〔The invention's effect〕

As described above, in the case of the present invention, even if the gas pressure drops in the gas chamber of the breaker that is inserted in series in the transmission line to the other end substation, the break or the breaker is protected. There is an effect of getting.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an example of normal GIS equipment,
FIG. 2 is a diagram showing a control logic for a mutual interlock which is adopted when a gas pressure in a part of the gas chamber in the configuration is lowered, and FIG. 3 is a diagram in which the gas pressure is lowered in a specific gas chamber. FIG. 4 is a diagram showing a remote trip control system based on mutual interlocking in this case, FIG. 4 and FIG. 5 are diagrams showing configurations of a transmitter and a receiver in the system, and FIGS. 6 and 7 are specific diagrams. The figure which shows the control system which concerns on the remote trip control taken when the gas pressure falls a little in the gas chamber, and FIG. 8 relates to the present invention which assumes the case where the gas pressure falls in a specific gas chamber. It is a figure which shows a control logic and a control system. 1,21,46 ... Line switch, 2,12,12
A, 22, 47 ... Shinya breaker, 3, 13, 13A, 2
3, 48 ... Disconnector, 4, 4A, 49 ... Busbar,
5, 25 ... Transmission line, 6-9, 17, 17A, 18, 1
8A, 26-28 ... Gas chamber, 37, 38, 81, 82
... AND circuit, 32 to 36 ... OR circuit, 79, 80
...... Timer.

Claims (1)

[Claims] 1. Busbars each housed in an insulating gas chamber, a disconnector connected to the busbar, a sushi breaker connected to the disconnector, and a line switch connected to the sushi breaker. A method for protecting GIS equipment in the case where a substation including a substation is connected to a substation via a transmission line, and when the disconnector and line switch are closed, As the gas pressure in the room, the load current cannot be cut off or cut off, but if a decrease in gas pressure within the range that can maintain the required insulation is detected, the above-mentioned breaker or breaker at the other end substation should be used. After the corresponding sign or breaker is tripped, the sign or breaker related to the above gas pressure drop is tripped, and then the disconnector and the line switch arranged adjacent to the sign or breaker are opened. How to protect GIS equipment.