JPH0589755A - Compressed gas breaker - Google Patents

Abstract

PURPOSE:To provide a compressed gas breaker capable of providing the optimum breaking characteristic required by an electric circuit, never generating a harmful over voltage at the time of breaking a small current, and capable of suppressing the strength of a braking device and the consumption of the driving energy of a driving device at minimum. CONSTITUTION:As a driving device, a driving device 5 having a fixed part 4 consisting of an iron core and a coil and a metal plate-like movable part 3 is used. The driving device desirably has a memory device 7 for storing a plurality of preliminarily set driving characteristic patterns, and at the time of opening, an optimum driving characteristic pattern is selected from the memory device according to circuit condition, and a movable contact is driven according to the selected driving characteristic pattern. The driving device more desirably has a power source device 9 consisting of a storage battery, or a large capacity capacitor and a charging circuit. A power generated in the braking process of the operation of a breaker is supplied to the power source device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-pressure type compressed gas circuit breaker, and more particularly to a compressed gas circuit breaker in which the driving device is improved so as to obtain optimum operating characteristics according to the type of operation of the circuit breaker. Regarding

[0002]

BACKGROUND OF THE INVENTION Circuit breakers are required to open circuit under many circuit conditions. For example, a circuit in which a short circuit current of tens of thousands of amperes flows may be cut off, while a circuit in which there is almost no current may be cut off. FIG. 3 is a view showing a general single pressure type compressed gas circuit breaker, and is a cross-sectional view showing a schematic configuration of a circuit breaker in an arc extinguishing chamber. As shown in FIG. 3, the movable contact portion 11 and the fixed contact portion 12 are arranged to face each other in the arc extinguishing chamber filled with a gas having excellent insulating properties. In the movable contactor portion 11, an arc extinguishing nozzle 14 and a movable energizing contactor 15 are sequentially arranged on the outer periphery of the movable arc contactor 13, and these are arranged in a cylinder 16
It is fixed to the flange portion of and is driven integrally by a driving device (not shown). A piston 17 is inserted into the cylinder 16 and is fixed to a fixed portion (not shown) inside the arc extinguishing chamber. On the other hand, in the fixed contact portion 12, a fixed current contact 19 is arranged on the outer circumference of the fixed arc contact 18, and is fixed to a fixed portion (not shown) in the arc extinguishing chamber.

When the single-pressure type gas circuit breaker is opened as described above, the movable contact portion 11 is moved by the driving device to move the movable / fixed energizing contact elements 15, 19 first.
The space is separated, and then the movable / fixed arc contactors 13, 1
8 is separated, and the movable / fixed arc contactors 13, 18 are separated.
An arc 20 is generated in the meantime. On the other hand, the gas in the cylinder 16 is compressed by the relative movement of the cylinder 16 and the piston 17 accompanying the movement of the movable contactor 11. The compressed gas becomes a high-speed gas flow and is blown to the arc 20 through the arc extinguishing nozzle 14 to extinguish the arc 20.

In particular, in such a single pressure type compressed gas circuit breaker, when breaking a circuit through which a large current of tens of thousands of amperes such as a short circuit current flows, the movable contact portion 11 is driven at high speed by a strong force. It is necessary to extinguish the arc 20 generated between the movable / fixed arc contactors 13 and 18 by generating a high-pressure compressed gas and powerful blowing. further,
The heat of the arc 20 causes the gas to expand and become a high pressure,
Since a large reaction force may act on the drive device, a high output device capable of generating a large force at high speed must be used as the drive device. As a driving source of the driving device, compressed gas, a conductive spring, hydraulic pressure, etc. are generally used.

[0005]

However, as described above, when a high output drive device is used in the single pressure type compressed gas circuit breaker, the following problems occur.

That is, it is extremely rare for a circuit breaker to interrupt a large current such as a short circuit current, and a general open circuit operation is a small current or an open circuit operation in which almost no current flows. A small drive output is sufficient as the drive output for performing such a circuit opening operation. Therefore, the circuit breaker always wastes excessive drive energy in a general open circuit operation. In addition, in the open circuit operation in the state where a small current or almost no current flows, if the drive output is excessive, it may cause harmful overvoltage. Furthermore, the circuit breaker is required to have sufficiently strong braking and mechanical strength in order to accommodate the excessive output of the drive. In particular, in the vicinity of the end point of the open circuit operation (except when a strong reaction force is generated when the large current is cut off as described above), it is generally necessary to exert a strong braking force. Most of the energy is consumed by the braking device. Therefore, the circuit breaker consumes a large amount of driving energy during the opening operation, especially due to the braking device.

As described above, the conventional single pressure type compressed gas circuit breaker has a strong braking device and high mechanical strength in order to break a low frequency large current such as a short circuit current. In a general open circuit operation, there is a drawback that excessive driving energy is wasted.

The present invention has been proposed in order to solve the problems of the prior art as described above, and an object thereof is to realize a drive device which can obtain an optimum drive characteristic according to a circuit condition. By doing so, it is possible to obtain the optimum cutoff characteristics required by the electric circuit, no harmful overvoltage is generated when a small current is cut off, and the strength of the braking device and the consumption of driving energy of the driving device can be reduced to the required minimum. An object is to provide an excellent compressed gas circuit breaker that can be suppressed to the limit.

[0009]

In the compressed gas circuit breaker according to the present invention, the movable contact is opened by the driving force of the driving device, and the arc extinguishing performance is excellent due to the relative movement of the cylinder and the piston accompanying this operation. Compress the gas and move it
In a single-pressure type compressed gas circuit breaker for blowing on an arc generated between fixed contacts, the drive device is a drive device having a fixed part composed of an iron core and a coil, and a metal plate-shaped movable part. ..

That is, since the drive device of the present invention has a linear motor, for example, as is seen in the drive of an elevator, the patterns required for the acceleration / deceleration of the drive are input in advance and various patterns are formed. Accordingly, it is possible to easily generate various drive outputs. Therefore, the drive device is provided with a storage device that stores a plurality of preset drive characteristic patterns, and when the circuit is opened, the optimum drive characteristic pattern is selected from the storage device according to the circuit condition, and according to the selected drive characteristic pattern. It is desirable that the movable contact is configured to be driven.

Further, the drive device is generally configured to have a power supply device including a storage battery or a large-capacity storage device and a charging circuit. In this case, the driving device is preferably configured to supply the power supply device with the electric power generated in the braking process of the operation of the circuit breaker. The circuit conditions for opening the circuit breaker are detected beforehand by means such as a protection relay or intentionally determined from the system operation conditions. On the other hand, the breaker is generally provided with only the drive signal. This is because conventional circuit breakers can only accept drive signals.

[0012]

The operation of the present invention having the above construction is as follows. First, in the present invention, it is possible to perform appropriate switching of drive characteristics by using a linear motor as a drive device instead of using compressed gas / electric spring or hydraulic pressure. That is, since the linear motor can easily generate various drive outputs according to various drive characteristic patterns, it is possible to obtain optimum drive characteristics according to circuit conditions. Then, specifically, as described above, the optimum drive characteristic pattern is selected by using the storage device, and the movable contact is driven according to the selected pattern, so that the optimum required by the electric circuit is obtained. It is possible to obtain various blocking characteristics. Therefore, since the output of the drive device when the general small current is interrupted can be significantly reduced compared to the output when the large current is interrupted, the strength of the braking device of the circuit breaker itself can be reduced and the waste of drive energy can be effectively avoided. it can. Moreover, no harmful overvoltage is generated when the small current is cut off.

Further, when the electric power generated in the braking process of the operation of the circuit breaker is supplied to the power supply device, the driving energy consumed can be further reduced. That is,
Generally, driving a circuit breaker requires a large amount of power instantaneously, but such driving is intermittent. Therefore, when the power generated in the operation process of the circuit breaker is supplied to the power supply device, this energy can be accumulated and the accumulated energy can be used as a part of the driving energy for the next operation. Energy efficiency can be improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the compressed gas circuit breaker according to the present invention as described above will be specifically described with reference to FIGS. In this case, FIG. 1 is a principle view schematically showing the configuration of the entire compressed gas circuit breaker, and FIG. 2 is a perspective view showing a linear motor drive device. Since the present invention is characterized by the drive device, the specific configuration of the shutoff portion in the arc extinguishing chamber is not particularly shown, but, for example, the configuration shown in FIG. 3 may be applied. Is possible.

First, as shown in FIG. 1, the movable contact (not shown) of the arc-extinguishing chamber 1 of the circuit breaker is movable in the form of a metal plate through a connecting rod 2 mainly composed of an insulator. The pieces 3 are connected. The movable piece (movable part) 3 and the electromagnet (fixed part) 4 constitute a linear motor drive device 5. Further, as shown in FIG. 2, the movable piece 3 is
Generally, it is optimal to use an aluminum plate that is lightweight and has excellent conductivity. The electromagnet 4 is composed of an iron core and a coil of a groove portion, is arranged so as to sandwich the movable piece 3 from both sides, and the facing cross section is formed in a comb shape. Furthermore, it is generally optimal that the iron core forming the electromagnet 4 is composed of laminated silicon steel plates.

On the other hand, reference numeral 6 in FIG. 1 denotes an output device for giving an electric output corresponding to the drive characteristic pattern to the coil of the electromagnet 4, and reference numeral 7 denotes a storage device for storing a plurality of drive characteristic patterns. The storage device 7 is configured to select an optimum drive characteristic pattern and provide it to the output device 6 when a drive signal 8 accompanied by a drive condition corresponding to the circuit condition is given from a relay circuit (not shown) or the like. ing. A drive power supply (power supply device) 9 and a rectifying device 10 are connected to the output device 6. The drive power source 9 is composed of a storage battery or a large-capacity electric storage device. The rectifier 10 is provided to rectify the electric energy of the commercial frequency power source and charge the drive power source 9. The drive power source 9 is supplied with electric energy generated in the braking process by the linear motor drive device 5 through the output device 6.

In the compressed gas circuit breaker of the present embodiment having the above-mentioned configuration, when performing the open circuit operation, first, from the relay circuit (not shown), the storage device 7 is driven according to the circuit condition. The drive signal 8 with conditions is input.
As a result, the storage device 7 selects the optimum drive characteristic pattern and gives the selected drive characteristic pattern to the output device 6. Next, the output device 6 gives an electric output according to the drive characteristic pattern to the coil of the electromagnet 4. Due to this electric output, the electromagnet 4 generates a moving magnetic field according to the drive characteristic pattern, and as a result, an eddy current is generated in the movable piece 3 and the movable piece 3 is driven by an electromagnetic force.

Then, in accordance with the operation of the movable piece 3 of the linear motor driving device 5 as described above, the arc extinguishing chamber 1 is connected through the connecting rod 2.
The movable contact of is driven to perform the opening operation. Also,
Near the end point of the opening operation, a strong braking action can be easily realized by causing the electromagnet 4 of the linear motor drive device 5 to generate a moving magnetic field in the opposite direction. Further, the electric energy generated in the braking process by the linear motor driving device 5 is supplied to the driving power source 9 via the output device 6. As a result, energy is supplied to the drive power source 9 every time the circuit is opened, and this energy is
Since it is used as a part of driving energy for the next operation, energy efficiency can be improved.

The present invention is not limited to the above-mentioned embodiment, and the structure of the power supply device, the structure for supplying the drive signal, etc. can be freely selected. Also, the specific configuration of the circuit breaker body can be freely selected. That is,
The present invention has a special feature in the drive device, and as long as the circuit breaker has this feature, the configuration of each of the other parts can be freely selected. The effect is obtained.

[0020]

As described above, in the present invention, since the linear motor is used as the driving device, the optimum driving characteristic according to the circuit condition can be obtained.
It is possible to obtain the optimum breaking characteristics required by the electric circuit, no harmful overvoltage is generated at the time of breaking a small current, and the strength of the braking device and the consumption of driving energy of the driving device are suppressed to the necessary minimum. It is possible to provide a possible excellent compressed gas circuit breaker.

[Brief description of drawings]

FIG. 1 is a principle view schematically showing the configuration of the entire compressed gas circuit breaker in one embodiment of the compressed gas circuit breaker according to the present invention.

2 is a perspective view showing a linear motor drive device used in the compressed gas circuit breaker of FIG. 1. FIG.

FIG. 3 is a cross-sectional view showing a schematic configuration of a breaker in an arc extinguishing chamber in a general compressed gas circuit breaker.

[Explanation of symbols]

 1 ... Arc extinguishing chamber 2 ... Connecting rod 3 ... Movable piece (movable part) 4 ... Electromagnet (fixed part) 5 ... Linear motor drive device 6 ... Output device 7 ... Storage device 8 ... Drive signal 9 ... Drive power supply (power supply device) 10 ... Rectifier

Claims (4)

[Claims] 1. A movable contact is opened by a driving force of a driving device, and a relative movement of a cylinder and a piston accompanying this movement compresses a gas having an excellent arc extinguishing performance,
In a single-pressure type compressed gas circuit breaker for blowing on an arc generated between a movable / fixed contactor, the drive device is a drive device having a fixed portion composed of an iron core and a coil, and a metal plate-shaped movable portion. Characterized compressed gas circuit breaker. 2. The drive device has a storage device for storing a plurality of preset drive characteristic patterns, selects an optimum drive characteristic pattern from the storage means according to circuit conditions, and according to the selected drive characteristic pattern. The compressed gas circuit breaker according to claim 1, wherein the movable contactor is driven. 3. The compressed gas circuit breaker according to claim 1, wherein the drive device has a power supply device including a storage battery or a large-capacity electric storage device and a charging circuit. 4. The compressed gas circuit breaker according to claim 3, wherein the drive device is configured to supply power generated by the braking process of the operation of the circuit breaker to the power supply device.