JP3351633B2 - Pole breaker device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pole breaker provided between two neutral wires connected between poles of a bipolar converter installed in a conversion station of a DC transmission system.

[0002]

2. Description of the Related Art In a conversion station of a DC transmission system, an AC-
DC converters are installed between the neutral and the + mains and between the neutral and the-mains, each of which is called a pole. DC transmission system is +
In the case of a main line, a main line and two neutral lines,
One pole may be stopped for operation, and a pole breaker is installed between the neutral conductors to separate the stopped pole from the operating pole.

In a conventional. +-. 250 kV DC power transmission system, a switchgear of a conversion station is generally an air-insulated type, and employs a structure as shown in FIG. 8 using a vacuum circuit breaker or the like as a pole breaker. Was.

That is, as shown in FIG. 8, in order to provide a vacuum circuit breaker 2 between two neutral wires 1 and to cut off a DC current by the pole breaker, it is necessary to generate a zero point in the DC. Therefore, an oscillation circuit (LC circuit) including the reactor L and the capacitor C is connected in parallel to the vacuum circuit breaker 2 via the closing switch 24, and the overvoltage limiting device 1
8 in parallel, and a capacitor C
A charging device for charging the battery was installed.

If the pole breaker having the above-described structure is used, when the current is cut off at time 27 by a closing switch as shown in FIG. 9, the DC current 20 oscillates by the LC circuit and becomes a high-frequency current 26 to become a zero point. Since 28 occurs, the DC current is cut off at this zero point.

In this case, it is necessary to always charge the capacitor of the LC circuit installed in parallel with the breaking section of the pole breaker, and a charging device for charging the capacitor is installed separately from the pole breaker body. As a result, the size of the equipment is inevitable.

[0007] Recently, a ± 500 kV DC transmission system has been studied. However, in this transmission system, there is a concern that the size of a switchgear of a substation is increased due to an increase in transmission voltage.

[0008]

As described above, the conventional ± 2
In a 50 kV DC transmission system, a pole breaker provided between the two neutral conductors connected between each pole of the bipolar converter installed at the conversion station to separate the stop pole from the operation pole. A vacuum circuit breaker was used as a circuit breaker, and an LC circuit for making a zero required for breaking was connected in parallel to the breaker, but a vacuum circuit breaker was used to charge the capacitor C of the LC circuit. A charging device is required,
The equipment becomes larger.

Further, in the ± 250 kV DC power transmission system which has been recently studied, each equipment tends to be larger and the installation space occupied by the pole breaker becomes larger.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a gas circuit breaker for a pole breaker provided in the case of unipolar operation, and to create a zero point in a DC current. An object of the present invention is to provide a pole breaker device that can reduce the installation area by eliminating the need for a charging device for charging a capacitor.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises a pole breaker device by the following means.

[0012]

[0013]

[0014]

According to a first aspect of the present invention, a plurality of converters are connected in a bipolar manner , and one of the converters is connected to the + main line, and the other is connected to the-main line. ,
Further, a neutral wire is connected to each pole, and a vibration circuit and an overvoltage limiting device each consisting of a reactor and a capacitor are connected in parallel to the main breaker, and an auxiliary breaker is connected in series to the main breaker. In a conversion station of a DC transmission system in which a neutral circuit protection circuit breaker device is installed between at least one of the neutral conductors and the ground, the neutral pole is provided between the neutral conductors of the respective poles, and the stop pole is operated. A pole breaker consisting of a gas breaker for separating from the side pole,
An oscillation circuit comprising a reactor and a capacitor connected in parallel with the pole separation circuit breaker and generating an oscillating current at the time of current interruption, and supporting the neutral line protection circuit breaker device after the current interruption by the pole separation circuit breaker. An overvoltage generated between the poles of the pole separation circuit breaker when the circuit breaker is turned on is suppressed by an overvoltage limiting device of the neutral line protection circuit breaker device.

The invention corresponding to claim 2 is the invention according to claim 1.
In the pole separation circuit breaker device according to the invention, the auxiliary switch opened after the overvoltage generated between the poles of the pole breaker is suppressed by the overvoltage limiting device of the line protection circuit breaker device for pole separation. It is connected in series with the vessel.

According to a third aspect of the present invention, a plurality of converters are connected in a bipolar manner , and one of the converters is connected to the + main line, and the other is connected to the-main line. ,
Further, a neutral wire is connected to each pole, and a vibration circuit and an overvoltage limiting device each consisting of a reactor and a capacitor are connected in parallel to the main breaker, and an auxiliary breaker is connected in series to the main breaker. At the conversion station of the DC power transmission system where the neutral line protection circuit breaker device is installed between at least one of the neutral lines and the ground, the stop side pole is placed between the neutral side of each pole from the operation side pole. A pole breaker consisting of a gas breaker for separation is provided, and when the pole breaker is opened, the auxiliary breaker of the neutral protection circuit breaker device is turned on, and the oscillating current at the time of current breaking is applied to the vibration. An overvoltage generated by a circuit and generated between the poles of the pole breaker after current interruption is suppressed by the overvoltage limiting device.

[0018]

[0019]

[0020]

[0021]

According to the pole breaker device of the present invention corresponding to claim 1 , the pole breaker is connected in parallel with a vibration circuit comprising a reactor and a capacitor for generating a vibration current at the time of current break in parallel with the pole breaker. the oscillating current is generated, since so as to suppress the overvoltage limiting device neutral protection breaker device overvoltage generated between poles of pole separation breaker after the current cutoff by pole separation breaker, equipment
Can be reduced in installation area.

According to a pole breaker device of the invention corresponding to claim 2 , in addition to the function and effect of the invention corresponding to claim 1 , an overvoltage generated between the poles of the pole breaker after the current is cut off. Is stopped by the overvoltage limiting device of the neutral protection circuit breaker device, the stop side pole is separated from the operation side pole by opening the auxiliary switch provided in series with the pole separation circuit breaker.

According to a third aspect of the present invention, there is provided a pole breaker device comprising a gas breaker between neutral wires, and a neutral wire protection breaker at the time of current cutoff. Oscillation current is generated by the oscillation circuit of the device,
Since the overvoltage generated between the poles of the pole separation circuit breaker after current interruption is suppressed by the overvoltage limiting device of the neutral line protection circuit breaker device , the installation area of the equipment can be reduced.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a system configuration diagram of a conversion station showing a first embodiment of a pole breaker device according to the present invention.

In FIG. 1, reference numeral 1 denotes two neutral wires connected to each pole of the bipolar converter, and SF between the two neutral wires.
6 Gas-insulated pole breaker 2 is connected. A vibration circuit (LC circuit) 17 including a reactor L and a capacitor C is connected in parallel with the pole breaker 2 via an auxiliary switch 19 in series, and an overvoltage limiting device 18 is connected in parallel with the LC circuit 17. Is connected.

Further, a neutral line overvoltage limiting device 3 is installed between each neutral line 1 and the ground, and a surge capacitor 4 is installed respectively.

On the other hand, a neutral protective circuit breaker is connected to two neutral conductors 1 connected between the respective poles of the bipolar converter. Neutral wire protection circuit breakers
The main circuit breakers 5 and 12 are installed between the ungrounded end and the ground, and the LC circuits 6 and 9 including reactors and capacitors and the overvoltage limiting devices 7 and 10 are connected in parallel with the main circuit breakers 5 and 12, respectively. Further, auxiliary breakers 8, 11 which are open during normal system operation are provided in series between the non-grounded side of the neutral conductor 1 and the main circuit breakers 5, 12; In the case of a ground fault, the fault current flowing from the ground fault point to the ground terminal flows in to protect the neutral conductor.

Next, the operation of the pole breaker configured as described above will be described.

Now, as shown in FIG.
When the + main pole or the − main pole is stopped when the converters 16 of the respective poles are operated together with the power supply being turned on, the transmission current is transmitted through the two neutral conductors through the pole separation circuit breaker 2. 1, the pole separation circuit breaker 2 is opened by the following means to separate the stop side pole from the operation side pole, and the neutral current on the stop pole side to the operation side neutral wire. Commutate.

That is, when the direct current is cut off, the pole breaker 2 is opened, and at the same time, the pole breaker auxiliary switch 19 is opened.
Input. Then, an arc is generated in the pole separation circuit breaker 2. At this time, the pole separation circuit breaker 2 and the LC circuit form a closed circuit, and as shown in FIG.
It becomes 1. That is, when the pole separation circuit breaker 2 is opened at the time point 23, the DC current 20 becomes the oscillating current 21 and the amplitude of the oscillating current increases with time and becomes zero at the time point 22.
, The current is interrupted by the pole separation circuit breaker 2.

An overvoltage is applied between the poles of the pole breaker 2 simultaneously with the interruption of the current. This overvoltage is suppressed by the overvoltage limiting device 18 already turned on by the auxiliary switch 19. Thereafter, by opening the auxiliary switch 19, the respective poles are disconnected, and the stop-side pole is separated from the operation-side pole.

As described above, in the first embodiment, the pole separation circuit breaker 2 provided between the two neutral wires 1 connected to the respective poles of the bipolar converter is a gas circuit breaker. Since the LC circuit 17 and the overvoltage limiting device 18 are connected in parallel with each other, and the auxiliary switch 19 is connected in series with them, a charging device for charging the capacitor C of the LC circuit 17 becomes unnecessary. The installation area of the equipment can be reduced.

FIG. 3 shows a second embodiment of the pole separation circuit breaker according to the present invention. The same parts as those in FIG. 1 are denoted by the same reference numerals, and only different points will be described here.

In the second embodiment, as shown in FIG. 3, an auxiliary switch 19 is connected in series to the pole breaker 2, and the LC circuit 17 and the overvoltage limiter 1 are connected in parallel to the pole breaker 2.
8 are connected.

In the pole breaker device having such a configuration, the auxiliary switch 19 and the pole breaker 2 are normally turned on, and when the pole breaker 2 is opened at the time of current breaking, an arc current generated from the breaking section is generated. Oscillation is caused by the LC circuit 17, and current is interrupted by the pole separation interrupter 2 at a current zero point generated by the oscillating current. At this time, an overvoltage generated between the poles of the pole breaker 2 is suppressed by the overvoltage limiting device 18, and the auxiliary switch 19 is thereafter opened to disconnect the stop-side pole from the operation-side pole.

The same function and effect as in the first embodiment can be obtained also in the pole separation circuit breaker device having such a configuration.

FIG. 4 shows a third embodiment of the pole breaker device according to the present invention. The same parts as those in FIG. 1 are denoted by the same reference numerals, and only different points will be described here.

Generally, a conversion station is provided with a breaker device for protection of a central line. In this circuit breaker device for protecting a central line, as described in the first embodiment, the main circuit breakers 5 and 12 are installed between the non-grounded end of the neutral conductor 1 and the ground. , 12 are connected in parallel with LC circuits 6, 9 each consisting of a reactor and a capacitor, and overvoltage limiting devices 7, 10, and a normal system is connected between the non-grounded side of the neutral line 1 and the main circuit breakers 5, 12. In operation, the auxiliary circuit breakers 8 and 11 that are open are provided in series, and the fault current flowing from the ground fault point to the ground end from the ground fault point of the neutral wire 1 is protected by protecting the neutral wire. Is what you do.

Therefore, in the third embodiment, as shown in FIG. 4, the pole separation circuit breaker device is constituted only by the pole separation circuit breaker 2 and the LC circuit 17 connected in parallel to the circuit breaker 2. The auxiliary circuit breaker 8 or 11 of the neutral line protection circuit breaker device is turned on, and the overvoltage generated between the poles of the pole separation circuit breaker 2 after the current interruption is reduced to the overvoltage limiting device 7 or 10 of the neutral line protection circuit breaker device. This is to suppress it.

According to the pole breaker device having such a configuration, the overvoltage limiter 7 or 10 of the neutral line protection breaker device is used in common, so that the overvoltage limiter for the pole breaker is unnecessary. Thus, the installation area of the equipment can be further reduced as compared with the first and second embodiments.

FIG. 5 shows a fourth embodiment of the pole breaker device according to the present invention. The same parts as those in FIG. 4 are denoted by the same reference numerals, and only different points will be described here.

In the fourth embodiment, as in the third embodiment, the overvoltage limiting device 7 or 10 of the circuit breaker device for neutral protection is used.
However, the auxiliary switch 19 is connected in series to the pole breaker 2 to which the LC circuit 17 is connected in parallel.

The pole-separated circuit breaker device having such a configuration also has the same configuration as that of the pole breaker device except that the opening timing of the auxiliary switch 19 at the time of current interruption is after overvoltage suppression by the overvoltage limiting device 7 or 10 of the neutral line protective circuit breaker device. The operation is the same as that of the third embodiment, and the installation area of the equipment can be further reduced as compared with the first and second embodiments.

FIG. 6 shows a fifth embodiment of the pole separation circuit breaker according to the present invention. The same parts as those in FIG. 4 are denoted by the same reference numerals, and only different points will be described here.

In the fifth embodiment, as shown in FIG. 6, a pole breaker device is constituted only by a pole breaker 2 composed of a gas breaker. Circuit 6 or 9 and overvoltage limiting device 7 or 1
0 is shared.

In the pole breaker of the above construction, when the auxiliary breaker 8 or 11 of the neutral protection circuit breaker is turned on at the time of current interruption, an oscillating current is generated by the LC circuit 6 or 9. The pole breaker 2 is opened at the zero point of the oscillating current. After the pole breaker 2 has cut off the current, the overvoltage applied between the poles is suppressed by the overvoltage limiting device 7 or 10. Then, after the overvoltage is suppressed, the auxiliary circuit breaker 8 or 11 is opened, and the current interruption is terminated.

Therefore, in the fifth embodiment, since the LC circuit and the overvoltage limiting device of the neutral protection circuit breaker device are shared, the pole separation circuit device comprising a gas circuit breaker is used as the pole breaker device. It is only necessary to provide a vessel, and the size of the equipment can be further reduced as compared with the third embodiment.

FIG. 7 shows a sixth embodiment of the pole breaker device according to the present invention. The same parts as those in FIG. 4 are denoted by the same reference numerals, and only different points will be described here.

In the sixth embodiment, as shown in FIG. 7, a pole separation circuit breaker 2 composed of two gas circuit breakers is provided in series. The overvoltage limiting device is shared with the LC circuit of the device.

With such a configuration, the size of the equipment can be further reduced as compared with the third embodiment.

[0052]

As described above, according to the present invention, the pole breaker provided in preparation for unipolar operation is used as a gas breaker, and a capacitor for charging a direct current to a zero point is charged. Since the charging device is not required, it is possible to provide a pole breaker device capable of reducing the installation area of the equipment.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing a first embodiment of a pole separation circuit breaker device according to the present invention.

FIG. 2 is a waveform chart showing an oscillating current generated by an LC circuit in the embodiment.

FIG. 3 is a system configuration diagram showing a second embodiment of the present invention.

FIG. 4 is a system configuration diagram showing a third embodiment of the present invention.

FIG. 5 is a system configuration diagram showing a fourth embodiment of the present invention.

FIG. 6 is a system configuration diagram showing a fifth embodiment of the present invention.

FIG. 7 is a system configuration diagram showing a sixth embodiment of the present invention.

FIG. 8 is a system configuration diagram showing a conventional pole separation circuit breaker device.

FIG. 9 is a vibration waveform diagram by an LC circuit of the device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Neutral wire, 2 ... Pole breaker, 3 ... Neutral wire overvoltage limiting device, 4 ... Surge capacitor, 5, 12 ...
... Main circuit breaker for neutral protection, 6,9 ... LC circuit for neutral protection, 7,10 ... Overvoltage limiting device for neutral protection, 8,11 ... Auxiliary breaker, 17 ……………………………………………………………………………………………… …………………………………………………………………………………………………………………………………….

──────────────────────────────────────────────────続 き Continuing on the front page (72) Tadashi Koshizuka, 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Hamakawasaki Plant (72) Susumu Nishiwaki 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture No. Inside the Toshiba Hamakawasaki Plant (72) Masayuki Ishikawa 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture Inside (72) Inventor Hirokazu Ohashi 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki City, Kanagawa Prefecture No. Within the Toshiba Hamakawasaki Plant (72) Inventor Naoaki Takeharu 3-3-22 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Inside Kansai Electric Power Company (72) Inventor Hiroshi Sugihara 2-5 Marunouchi, Takamatsu City, Kagawa Prefecture Shikoku Electric Power (72) Inventor Masayuki Hatano 6-15-1, Ginza, Chuo-ku, Tokyo Power Supply Development Co., Ltd. (56) References JP-A-59-103253 ( JP, A) JP-A-59-184411 (JP, A) JP-A-57-162223 (JP, A) JP-A-57-168432 (JP, A) JP-A-59-37622 (JP, A) JP-A-57-148828 (JP, A) JP-A-57-145226 (JP, A) JP-A-59-66025 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01H 33 / 59 H02H 3/00 H02J 1/00 301

Claims (3)

(57) [Claims] 1. A plurality of converters are connected in a bipolar form, and one of the converters is connected to the positive main line, the other is connected to the negative main line, and each of the converters is neutral. A neutral circuit is connected to each of the wires, and the main circuit breaker is connected to an oscillating circuit consisting of a reactor and a capacitor, and an overvoltage limiter is connected in parallel to each other, and the main circuit breaker is further connected to an auxiliary circuit breaker in series. At a conversion station of a DC transmission system in which a circuit breaker device is installed between at least one of the neutral conductors and the ground, provided between the neutral conductors of the respective poles to separate the stop-side pole from the operation-side pole. And a vibration circuit comprising a reactor and a capacitor connected in parallel with the pole breaker and generating an oscillating current at the time of current cutoff. After the current is cut off, the auxiliary breaker of the neutral protection circuit breaker device is turned on, and the overvoltage generated between the poles of the pole separation circuit breaker is suppressed by the overvoltage limiting device of the neutral protection circuit breaker device. A pole breaker device, characterized in that: 2. The pole breaker device according to claim 1, wherein the auxiliary voltage is released after an overvoltage generated between the poles of the pole breaker is suppressed by the overvoltage limiting device of the breaker device for neutral protection. A pole breaker device wherein a switch is connected in series with the pole breaker. 3. A converter in which a plurality of converters are connected in a bipolar manner, a converter having one of the positive poles is connected to a main line on the other side, and a converter having a negative side is connected to a main line on the negative side. A neutral circuit is connected to each of the wires, and the main circuit breaker is connected to an oscillating circuit consisting of a reactor and a capacitor, and an overvoltage limiter is connected in parallel to each other, and the main circuit breaker is further connected to an auxiliary circuit breaker in series. In a conversion station of a DC transmission system in which a circuit breaker device is installed between at least one of the neutral conductors and the earth, a gas shutoff for separating a stop-side pole from an operation-side pole between the neutral conductors of the respective poles. A pole breaker made of a device, when the pole breaker is opened, an auxiliary breaker of the neutral protection circuit breaker device is turned on, an oscillating current at the time of current interruption is generated by the oscillating circuit, and Current The pole separation pole separation circuit breaker device, characterized in that the overvoltage generated and so as to be suppressed by the overvoltage limiting device between the poles of the circuit breaker after disconnection.