JPS6378419A - Vacuum breaker - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a vacuum circuit breaker that operates independently for each phase.

(Prior art) Generally, this type of vacuum circuit breaker has a rating of 6KV to 36K.
V grade is often used, and recently, about 72~
It is also used for large capacity devices of about 84KV and about 168KV.

On the other hand, vacuum circuit breakers with a rated voltage of about 168KV or less adopt an independent operation method for each phase, and the three phases of a three-phase circuit breaker are
At the same time, it performs closing and opening operations.

However, for power system circuit breakers with a nominal voltage of 154 KV or higher, a single-phase + Ij closing system is sometimes applied to improve transient stability, and in this case, each phase of the three-phase circuit breaker is independent A type of "independent operation method for each phase" that closes and opens circuits is required.

On the other hand, air circuit breakers, gas circuit breakers, and the like are common as circuit breakers that operate independently for each phase, and the circuit breaker is often operated using compressed air. This compressed air operation can be performed relatively easily in both three-phase simultaneous operation (three-pole single-throw method) and each phase independent operation method by switching the solenoid valve, and it is also possible to simultaneously close and open three phases. , can be easily reduced by making the conductance of the piping system of each phase the same.

By the way, in places where the power system has not been sufficiently expanded, the single-phase recirculation method may be adopted not only for circuit breakers of approximately 154KV or higher, but also for circuit breakers of approximately 66KV. There is a need for a vacuum circuit breaker that can be operated independently.

In general, a vacuum circuit breaker is a simple circuit breaker that eliminates the need for anchorage attached to the compressors' and 9, and can be operated with a small-capacity DC power supply, and the operation of this type of circuit breaker is The mechanism uses either an electric spring operating mechanism or a solenoid operating mechanism.

A vacuum circuit breaker with an independent operation method for each phase that has already been proposed is equipped with an electric spring operation mechanism, as shown in FIG. 6.The operation of this vacuum circuit breaker is as shown in FIG. By energizing the closing electromagnetic coil a and the trip electromagnetic coil b, each of the first, second, and third vacuum valves cS
Closing and opening operations of d and e are performed.

That is, in FIG. 6, when the circuit is closed, the closing electromagnetic coil a
When energized, the closing latch f interlocked with the closing excitation coil a releases the locking portion g1 of the closing cam member g, so that the closing cam member g rotates to the right around the pivot with the stored elasticity of the closing spring i. swirl Then, the cam portion g2 of this input cam member g
pushes the cam roller j that is in contact with it, so the operating rod k that supports this cam roller j rotates to the right around its pin axis g, and furthermore, this operating rod l (is connected to it via the connecting rod m). Since the main arm rod 0, which is integral with the connected main shaft n, is rotated to the left around the main shaft n, each operating arm rod psqsr pivoted on this main shaft n is connected to each movable electrode of each vacuum valve C1d, e. Each link sS t, u of C1, dl, el is pushed through each coil spring ■1, ■2, ■3, and the above-mentioned first and second
, each fixed electrode C2, d of each third vacuum valve c, d, e
The movable electrodes C1, dt, and et are connected to l and e2 to close the circuit.

Next, when the circuit opens, the above trip? When the l1la coil b is energized, the closing trip latch X that is interlocked with the trip electromagnetic coil b disengages the locking roller 2 against the elasticity of the trip spring y, so that the latch arm supported by the locking roller 2 The rod Z rotates to the left around the support shaft z3 by the elasticity of the spring z2, and the cam roller j, which is connected to it through the connecting rod Z4, turns to the left around the bottle axis g. Thus, each movable electrode C1, dl, el is separated from each fixed electrode C2, d 2 % e 2 and opened in the reverse order of the above-described operation.

(Problem to be Solved by the Invention) However, the closing magnetic coil a and the tripping magnetic coil b in the above-mentioned vacuum circuit breaker with independent operation for each phase have a maximum variation of about 5% (operating error) in terms of DC resistance. ), and furthermore, since there are variations in the elasticity of each spring of each electric spring operating mechanism, the closing time and opening time of the first, second, and third vacuum valves C1d and e will vary by approximately 3. ~
This causes an operational error of about 15m5ec.

However, even when using a solenoid operating device (t) instead of the electric spring operating mechanism, this solenoid itself has IIi
There are variations in the flowing current, and as described above, variations occur in the opening time and closing time of each vacuum valve c, d, and e.

Furthermore, although it varies depending on the neutral point grounding conditions of the power system, in the case of ineffective grounding or resistance grounding, even if the circuit breaker opens and closes all three phases at the same time, the official order of the main circuit, and the circuit breaker will be placed in the second or third position. In each phase of
The arc current caused by the pre-arc is large and the arcing time becomes longer in the case of interruption), therefore, the damage to each electrode becomes severe and the service life is shortened. However, since the closing phase and the shutting phase differ each time the closing and shutting operations are performed, the order of closing and shutting off also changes, and overall there is no difference in damage to the electrodes depending on the phase.

However, if there is an operating time difference between each phase when each vacuum valve closes and opens, the larger the operating time difference, the more likely the electrical closing and shutting order and the mechanical closing and opening order will be. They tend to be the same, but the damage to the electrodes differs depending on the phase of the vacuum circuit breaker mentioned above, causing problems.

The present invention has been made in view of the circumstances described above, and is intended to reduce the operating time difference (dispersion) of the three phases during closing and opening operations in a vacuum circuit breaker in which each phase is operated independently. It is an object of the present invention to provide a vacuum circuit breaker in which the difference in damage to each electrode depending on the phase is minimized to improve operating accuracy.

[Structure of the invention]

(Means for solving the problems and their effects) The present invention includes:
In a vacuum circuit breaker in which each phase is independently operated, each electromagnetic clutch is provided at the connecting portion of each main shaft of each phase so as to be able to connect and disconnect, and each movable electrode of each vacuum valve is operated on each of the main shafts. Each operating arm is pivoted, and each operating device is connected externally to each operating arm to open and close three phases simultaneously, such as during single-phase recirculation, three-phase recirculation, and equipment inspection. Each electromagnetic clutch is operated to selectively turn on a single phase and turn on three phases to open and close a circuit.

(Embodiment) Hereinafter, an illustrated embodiment in which the present invention is applied to a vacuum circuit breaker of an independent operation type for each phase will be described.

In FIGS. 1 to 3, reference numerals 1.2.3 indicate the main shafts of a vacuum circuit breaker with independent operation for each phase, and the main shafts 1.2.3 are arranged in a straight line. , each connecting portion of each main shaft 1.2.3 is provided with each electromagnetic clutch 4 as shown in FIG. That is,
As shown in FIG. 3, each electromagnetic clutch 4 has -
■Second: A flange 1a is formed on one main shaft 1, and the armature 5a is slid on the "biped main shaft" near this flange 1a in the axial direction with the key 5b, but it is not integrated with the main shaft 1. A return spring 5d is rotatably mounted between the flange 1a and the flange 5c of the armature 5a.
This armature 5a is brought into contact with the flange 5C by interposing the armature 5a, an engagement ff15e is formed on the end face of the armature 5a, and the yoke 6a is pivoted on the other main shaft 2 facing the engagement teeth 5e. Electromagnetic coil 6b on yoke 6a
is inserted into the yoke 6a, and a locking ff16c is configured to mesh with the engaging teeth 5e on the end surface of the yoke 6a.

Therefore, by energizing the electromagnetic coil 6b, the electromagnetic clutch 4 causes the armature 5 to move across the yoke 6a.
a is sucked against the elasticity of the return spring 5d, and the engaging tooth 5e is engaged with the engaging tooth 6C to connect the above-mentioned biaxial shafts 1 and 2,
This allows the main shaft 1.2 to be rotated as a single main shaft.

Next, the electromagnetic clutch 4 shown in FIG. 4 is a modification of the electromagnetic clutch 4 shown in FIG. A number of engagement holes 7a are bored in the outer circumference, and a flange 8 is formed on the other main shaft 2 facing the flange 1a.
a, a yoke 8b is attached to one side of this flange 8a, an electromagnetic coil 8C is inserted into this yoke 8b, and each armature 8d is attached to this yoke 8b and the above-mentioned flange 8a.
A return spring 8e is interposed between the flange of each armature 8d and the yoke 8b.

Therefore, this electromagnetic clutch 4 also has the same function as the electromagnetic clutch 4 described above.

On the other hand, as shown in FIG.
The base of each actuating arm 9.10.11 is pivoted to the , and the first,
The second and third operating mechanisms 12, 13, 14 are connected. Further, each of the free ends of each of the operating arms 9.10.11 is provided with a first, second, and third vacuum valve 15.16.1.
It is connected to 7. That is, each vacuum valve 15.1
6.17 is an insulating vacuum tank 15b, 16b forming each vacuum chamber 15a, 16a, 17a.

Each fixed electrode 15c, 16c, 17c is vertically installed in each fixed electrode 15c, 16c, 17c, and each movable electrode 15d, 16d is located in each vacuum tank 15b 116b, 17b located directly below each fixed electrode 15c, 16c, 17c.

Each of the fixed electrodes 15c and 116c are arranged so that 17d can be freely lowered in A.
, 17c, and one end of each movable electrode 15d, 16d, 17d is connected to each link (connection tF) via each coil spring 15e, 16e, 17e.
15f, 16f, 17f are connected, each link being connected to the free end of each said actuating arm 9.10.11.

On the other hand, the electric circuit shown in FIG. 2 is a control circuit incorporated in the vacuum circuit breaker of the present invention, and the electric circuit shown in FIG.
Command device (operation panel) 2 that operates each third operation mechanism
9, turn on each trip switch 18, 19, 20,
The off-actuated switches 21, 22, 23 are connected, and the trip switches 18, 20 are connected to the electromagnetic clutches 4. Each electromagnetic clutch 4 is turned on by a command from the command device 29.

It is connected to a clutch switch 24 that is turned off. Furthermore, each current detector (current transformer C, T) 25
．． 26, 27 are arranged so as to be able to detect the magnitude of the current, and each of the current detectors 25, 26, 27 is
It is connected to the command device 29 mentioned above. Note that a test switch 28 is attached to the power supply portions of the two command devices.

Therefore, the command device 29 detects the magnitude of the current flowing through each of the current detectors 25, 26, 27 in FIG. As a result, in the case of single-phase re-circuiting, the electromagnetic clutches 4 are not energized, and on the other hand, in the case of three-phase re-closing, the electromagnetic clutches 4 are energized, and the main shaft 1 .2.3 should be made into one rotating shaft so that power can be transmitted.

At this time, when the three-phase circuit is restarted, each drip switch 18
．． Since each electromagnetic clutch 4 must be connected before excitation of clutches 1 and 20, the command device 29 operates the clutch switch 24.

Hereinafter, the effects of the present invention will be explained.

(I) When restarting a single phase (when a ground fault occurs in any of the A, B, and C phases), in Figure 2, (1) Current detector 25.26 of the ground fault phase.
．． 27 increases.

(2) Next, the command device 29 commands the current detector 2
5. Either switch 2 of 26 or 27 for ground fault phase only
Turn on the a contact of 1.22.23, energize the coil of any trip switch 18.19.20, and interrupt the ground fault phase with the corresponding trip switch.

(3) After a certain period of time has elapsed, single-phase reclosing is performed. Note that the closing control circuit that performs this single-phase restart is well known and is not shown in the drawings.

(4) When the lit circuit is reclosed, the command device 29 described in -1- performs the following operation.

That is, even if the CT lightning current flowing through the current detector for recirculation is attenuating, the energization is continued.

Also, when the CT lightning current increases during the reclosing phase, the clutch switch 2 is activated by a command from the bipedal command device 29.
Turn on the a contact of each of the switches 21, 22, and 23, turn on the a contact of each of the switches 21, 22, and 23, and turn on the each trip switch. 18, 19, and 20 coils are energized, thereby performing three-phase cutoff.

(II) When 31 old-11 is closed (in case of 2-wire ground fault, 3-phase short circuit, etc.) (1) In Fig. 2, the CT lightning current of two or more phases increases and one of the current detectors 25. When 26 and 27 detect this, the command device 29 receives this detection signal.

(2) Then, the command device 29 turns on the a contact of the clutch switch 24, thereby exciting each electromagnetic clutch 4 and turning the main shaft 1.2.3 into a single rotating shaft.

(3) Next, according to the command from the command device 29, each a contact of each switch 21, 22, 23 is turned onL, each trip switch 18.1, and the coil of 20 is energized and turned off fL, three Perform phase cutoff.

(4) After a certain period of time, perform three-phase reclosing. Note that the closing control circuit that performs this three-phase reclosing operation is well known (not shown).

(5) When the three-phase circuit is restarted, the command device 29 performs the following operations.

That is, when all of the CT lightning currents flowing through the current detectors 25, 26, 27 in the third recirculation phase have attenuated, energization is continued.

If the CT lightning current of - group or more increases, check that the a contact of the clutch switch 24 is turned on, and then turn on the a contact of each switch 2L 22.23.
L, each coil of each trip switch 18, 19, 20 is energized and three-phase cutoff is performed.

(m) When simultaneously opening and closing three phases during equipment inspection, etc., in FIG. 2, (1) Turn on the test switch 28 connected to the command device 29 in advance.

(2) Next, the command device 29 turns on the a contact point of the clutch switch 24, thereby exciting each electromagnetic clutch 4 and turning the main shafts 1, 2.3 into one rotating shaft.

(3) Next, according to the command from the command device 29 described in -,
Each A contact of each switch 21, 22, 23 is turned on, each trip switch 18.1, and each coil of 20 are energized to cut off the three phases.

(4) If necessary, three-phase power is turned on using a power-on control circuit (not shown).

As shown in 2, when Sanwa Do 17 is operated, the closing operation and opening operation are performed by each closing clutch (corresponding to closing latch f in Fig. 6) attached to each of the operating mechanisms 12, 13, and 14, respectively. Of the trip latches and trip latches (corresponding to trip latch It is possible to close and open the circuit at the same time.

In this case, the time difference between each phase when three phases are simultaneously opened and closed is as follows.

That is, in the case of each of the electromagnetic clutches 4, when one of the closing latches or trip latches attached to each of the operating mechanisms 12, 13, and 14 is released, the torque that rotates the main shaft of the relevant phase is generated. The relevant phase waits at the point where the coupling torque of the electromagnetic clutch that prevents this is balanced, and when the last latch is released, it operates together with the phase that is waiting.

Therefore, a time difference between opening and closing occurs by the difference between the waiting position of the first unlatched phase and the position of the last unlatched phase. The time difference between opening and closing is
It can be made smaller by selecting the size of the electromagnetic clutch, the generated torque, etc.

Next, another embodiment of the present invention shown in FIG. 5 includes each electromagnetic clutch 30a on each main shaft 1, 2.3.

Each of the above operating mechanisms 12゜13.1 via 30b and 30c
4, and an operating mechanism 31 for simultaneous three-phase operation is provided on the main shaft 2 via an electromagnetic clutch 32.

Therefore, in this embodiment, when single-phase opening is performed, only the electromagnetic clutches 30a, 30b, and 30c are energized so that each phase can be operated independently.On the other hand, when performing three-phase opening, each of the above-mentioned Electromagnetic clutch 4 and other electromagnetic clutches 3
2 is excited, thereby enabling three-phase simultaneous operation. Particularly, in this embodiment, when the three phases are restarted, the three phases can be opened and closed completely simultaneously using only one operating machine 31.

〔Effect of the invention〕

As described above, according to the present invention, in a vacuum circuit breaker of each phase independent operation type, each electromagnetic clutch 4 is provided at the connecting portion of each main shaft 1, 2, 3 of each phase so as to be able to connect and disconnect, Each operating arm 9.10.11 for operating each movable electrode 15d, 16d, 17d of each vacuum valve 15.16.17 is pivotally attached to each of the main shafts 1.2.3. 10.1
Since each operating mechanism 12, 13, and 14 is connected to 1,
It is possible to reduce the difference in operation time of the third eye during closing and opening operations, reduce burnout of each electrode, and not only extend the life of the electrode but also improve operational accuracy.Furthermore, The present invention provides an electromagnetic clutch between the shafts of each phase in an electric spring-operated vacuum circuit breaker or a solenoid-operated vacuum circuit breaker. It is possible to selectively use a vacuum circuit breaker with a flexible operation method for each phase, and moreover, the vacuum circuit breaker with an independent operation method for each phase of the present invention is an electric spring operation method or a solenoid operation method. Also, during three-phase reclosing, the shafts of each Il[J are strongly fixed by electromagnetic clutches, so the time difference between opening and closing of each phase becomes small, and simultaneous opening and closing of three phases becomes r + J function. There is no longer a significant difference in electrode damage due to phase.

In addition, Poka standard B-125 and lEC-56 standard specify that the time difference between opening and closing of each phase during the opening and closing operation of the circuit breaker is 6 m5ec.
(B-125) or 1/2 cycle or less (IEC-5
6) Are there any regulations that must be met?According to the present invention, these standards can of course be fully satisfied.

[Brief explanation of the drawing]

FIG. 1 is a diagram of the vacuum circuit breaker of the present invention, FIG. 2 is a control circuit diagram incorporated in the invention, FIGS. 3 and 4 are sectional views of an electromagnetic clutch used in the present invention, FIG. 5 is a diagram showing another embodiment of the present invention, and FIG. 6 is a diagram of a conventional vacuum circuit breaker. 1.2.3... Main shaft, 4... Electromagnetic clutch, 9.1
0.11... Operating arm, 12.13.14... Operating mechanism, 15.16.17... Vacuum valve, 18.19
．． 20...Trip switch, 24...Clutch switch, 25.26.27...Current detector, 829.
...Command device.

Claims (1)

[Claims] In a vacuum circuit breaker with independent operation for each phase, each electromagnetic clutch is provided at the connecting portion of each main shaft of each phase so as to be able to connect and disconnect, and each actuator operates each movable electrode of each vacuum valve on each main shaft. A vacuum circuit breaker characterized in that an arm rod is pivoted and each operation mechanism is connected to each operating arm.