JPH04282520A - Breaker with closing resistance - Google Patents

Abstract

PURPOSE:To improve insulation recovery characteristic by quickening an insulation recovery speed of a closing resistance contact relating to a main contact at pole opening time while ensuring sufficient time for inserting closing resistance at closing time, in the case of a breaker with closing resistance increasing breaking capacity per one item of the breaker and decreasing a number of series breaking items. CONSTITUTION:A movable side closing resistance contact 2 is provided in a movable side electrode 12, a connecting link 6 and an insulation link 7, actuated at an equal angular speed, are provided in a fixed side electrode 15 to connect an insulation rod 3, for transmitting displacement of the movable side electrode 12 to the links 6, 7, to the connecting link 6 and to hold a fixed side making resistance contact 8 to the insulation link 7, and closing resistors 19, 20 are provided in a space between the fixed side electrode 15 and the fixed side making resistance contact 8.

Description

[Detailed description of the invention]

[Object of the invention]

0002

[Field of Industrial Application] The present invention relates to a circuit breaker equipped with a closing resistor, which is equipped with a closing resistor for suppressing the closing overvoltage that occurs when the circuit breaker is closed, and a closing resistor contact for opening and closing the closing resistor. This invention relates to a circuit breaker with closing resistance that has improved insulation recovery characteristics of its contacts.

0003

2. Description of the Related Art In recent years, the capacity of power transmission systems has increased, and the breaking capacity of circuit breakers used in substations and switchyards has tended to increase. Therefore, circuit breakers with closing resistance, which are excellent as large-capacity circuit breakers, are widely used. A circuit breaker with a closing resistor is a circuit breaker that is provided with a closing resistor electrically connected in parallel with the main contacts of the circuit breaker, and a closing resistor contact that opens and closes the closing resistor. In this circuit breaker with closing resistance,
When the circuit breaker is closed, the closing resistance contact is closed before the main contact, and the closing overvoltage can be suppressed by the closing resistance. As a result, excellent reliability can be exhibited even when interrupting large-capacity current.

FIG. 4 shows a conventional example of such a circuit breaker with closing resistance.
This will be explained in detail below. That is, in a tank (not shown) filled with insulating gas, a movable electrode 34 and a fixed electrode 33 having main contacts are provided facing each other. The fixed side electrode 33 is fixed in a tank (not shown), whereas the movable side electrode 34 is driven in the closing operation direction and the opening operation direction by an operation mechanism (not shown).

Further, the fixed electrode 33 is provided with a closing resistance contact 30 electrically connected in parallel with the main contact. This closing resistance contact 30 is provided with a spring 30a that is biased in the direction of opening operation, and has a structure in which it is wiped by this spring 30a. Further, in the gap between the closing resistance contact 30 and the fixed side electrode 33, a closing resistor 3 is provided to suppress the closing overvoltage.
1 and 32 are provided.

[0006] In the circuit breaker with a closing resistor having the above configuration, the closing resistor contact portion 3 is used to suppress the closing overvoltage.
The 0 closing operation is performed at an earlier timing than the main contact closing operation. This ensures sufficient time for inserting the closing resistor at the time of closing.

On the other hand, the opening operation of the closing resistance contact 30 is performed at an earlier timing than the opening operation of the main contact. That is, the insulation recovery speed (opening speed) of the making resistance contact 30 needs to exceed that of the main contact. This is to ensure excellent insulation recovery characteristics at the closing resistance contact 30 during opening. In conventional circuit breakers, the number of series breaking points of the main contact is relatively large, so the number of series breaking points of the making resistance contact placed in parallel with this is also large, and the insulation recovery characteristics of the making resistance contact at the time of opening are different from that of the main contact. We were able to have sufficient margin.

[0008]

Recently, there has been a remarkable improvement in the breaking performance of circuit breakers, with the breaking capacity per point increasing and the number of series breaking points decreasing. Along with this reduction in the number of series breaking points, the number of closing resistance contacts provided in parallel with the main contacts has also been reduced. As a result, the following problems occurred.

That is, when the circuit breaker is opened, the number of closing resistance contacts is reduced, so the insulation recovery speed on the closing resistance contact side is relatively reduced. When the insulation recovery speed continues to decrease and the insulation recovery speed of the making resistance contact becomes lower than the opening speed of the main contact, the main contact side undergoes insulation recovery before the making resistance contact side. In this case, there was a risk that re-ignition would occur on the closing resistance contact side.

[0010] Since the closing resistance contact does not have the function of interrupting large currents, such a phenomenon must be avoided. Therefore, in order to increase the insulation recovery speed of the closing resistance contact, the closing timing of the closing resistance contact is set later in the closing operation, which is contrary to the opening operation, and the opening timing of the closing resistance contact is set faster during the opening operation. Measures can be considered. However, if the closing timing of the closing resistor contact is set late, the closing resistor insertion time at the time of closing cannot be maintained sufficiently, resulting in a problem that closing overvoltage cannot be sufficiently suppressed.

The present invention has been made in view of the problems of the prior art as described above, and its purpose is to provide a closing resistor in which the breaking capacity per point of the circuit breaker is increased and the number of series breaking points is reduced. In circuit breakers with a closing resistor, the circuit breaker with a closing resistor ensures sufficient time for inserting the closing resistor at the time of closing, and improves insulation recovery characteristics by making the insulation recovery speed of the closing resistor contact faster than that of the main contact when opening. It is to provide a vessel.

[Configuration of the invention]

[0013]

[Means for Solving the Problems] In order to achieve the above object, the circuit breaker with closing resistance of the present invention houses a fixed side electrode and a movable side electrode each having a main contact in a tank filled with insulating gas. The movable side electrode is provided with an operating rod that drives the movable side electrode in the closing operation direction and the opening operation direction, and a movable side closing resistance contact electrically connected to the movable side electrode in parallel with the main contact; An insulating rod that transmits displacement is provided, and a link mechanism is provided on the stationary side electrode via an insulating part made of an insulator, and this link mechanism includes a connecting link and a holding member that operate at the same angular velocity in mutually opposite directions. comprising a link, and connecting the insulating rod to the connecting link,
Further, the holding link holds a fixed side making resistance contact which is electrically connected in parallel with the main contact opposite to the movable side making resistance contact, and is further provided in the gap between the fixed side electrode and the fixed side making resistance contact. This device is characterized by providing a closing resistor for suppressing closing overvoltage that occurs during closing operation.

[0014]

[Operation] The operation of the present invention having the above-mentioned structure is as follows. During the closing operation of the circuit breaker, the operating rod drives the movable electrode in the closing operation direction. When the movable side electrode moves in the closing operation direction, both the movable side closing resistance contact and the insulating rod provided on the movable side electrode move in the closing operation direction. When the insulating rod transmits the displacement to the link mechanism, the connecting link connected to the insulating rod moves in the closing operation direction, and the holding link, which operates at the same angular velocity in the opposite direction of this connecting link, moves in the opening operation direction. do. At this time,
The fixed side closing resistance contact held by the holding link also moves in the opening operation direction. On the other hand, since the movable closing resistance contact is moving in the closing operation direction, the movable closing resistance contact and the fixed closing resistance contact move closer to each other. Therefore, the closing resistance contact can close at a faster rate of insulation degradation than the main contact.

On the other hand, during the opening operation of the circuit breaker, the operating rod drives the movable electrode in the opening operation direction. When the movable electrode moves in the opening direction, both the movable closing resistance contact and the insulating rod provided on the movable electrode move in the opening direction. When the insulating rod transmits the displacement to the link mechanism section, the connecting link moves in the direction of the opening operation and the holding link moves in the direction of the closing operation, contrary to the closing operation. At this time, the fixed side closing resistance contact held by the holding link also moves in the closing operation direction. On the other hand, since the movable closing resistance contact is moving in the opening operation direction, the movable closing resistance contact and the fixed closing resistance contact move away from each other. Therefore, the closing resistance contact can be opened at a faster dielectric recovery rate than the main contact.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a circuit breaker with a closing resistor according to the present invention will be described in detail below with reference to FIGS. 1 and 2. FIG. 1 shows the shut-off state, and FIG. 2 shows the closed-on state.

In the figure, a movable electrode 12 and a fixed electrode 15 each having a main contact are housed in a tank 16 filled with insulating gas. Further, an operating mechanism 17 is provided outside the tank 16. This operating mechanism 17 is connected to the movable electrode 12 via an insulating rod 18 disposed within the operating tank 16 and the operating rod 1 . The insulating rod 18 and the operating rod 1 move in the horizontal direction (left and right in the figure) by the driving force from the operating mechanism 17,
In response to this displacement, the movable electrode 12 is driven to freely move toward and away from the fixed electrode 15, thereby performing closing and opening operations of the main contact.

A nozzle 13 is provided at the tip of the movable electrode 12, and the operating rod 1 is fixed to the base. The insulating rod 1 in the operating rod 1
Arms 4 and 5 extending in the vertical direction (in the vertical direction in the figure) are provided at the end portions connected to the arms 8 . this house,
One end of an insulating rod 3 that transmits the displacement of the movable electrode 12 to the fixed electrode 15 is provided at the tip of the arm 4 . On the other hand, a cylinder 10a is provided at the tip of the arm 5.

The cylinder 10a has an opening formed at the left end in the figure, and a movable closing resistance contact 2 is slidably housed inside the cylinder 10a, protruding from this opening. This movable side closing resistance contact 2 is electrically connected in parallel with the main contact of the movable side electrode 12. In addition, the cylinder 10a
A spring 11 that expands and contracts horizontally is housed inside.
The elastic force of the spring 11 biases the movable closing resistance contact 2 to the left in the figure.

Further, the fixed electrode 15 is provided with a connecting link 6 and an insulating link 7 that operate at the same angular velocity in opposite directions. Both links 6 and 7 constitute a link mechanism section. The other end of the insulating rod 3 is connected to the tip of the connecting link 6 . Further, the insulating link 7 is made of an insulating material, and a cylinder 10b is held at the tip thereof on the same axis as the cylinder 10a provided on the movable electrode 12. The cylinder 10b is an insulator 9
It is fixed to the stationary side electrode 12 by means of an opening, and an opening is formed at the right end in the figure. Further, a fixed-side closing resistance contact 8 is slidably housed in the cylinder 10b, protruding from this opening. That is, the insulating link 7 plays the role of a holding link and the role of an insulating part that insulates the fixed side closing resistance contact 8 and the fixed side electrode 15.

The fixed side closing resistance contact 8 is arranged so as to be able to come into contact with and separate from the movable side closing resistance contact 2, and is electrically connected in parallel with the main contact of the movable side electrode 12. Further, although not shown in the figure, a spring 11 that expands and contracts in the horizontal direction is housed in the cylinder 10b, similar to the cylinder 10a, and the elastic force of this spring 11 biases the fixed side closing resistance contact 8 in the right direction in the figure. has been done. When the movable side closing resistance contact 2 and the fixed side closing resistance contact 8 are closed, the spring 11
It has a structure that can be wiped by

Further, in the gap between the fixed side electrode 15 and the fixed side closing resistance contact 8, a closing resistor 19 is provided for suppressing the closing overvoltage.
20 are provided. These closing resistors 19 and 20 are electrically connected in series with the fixed closing resistor contact 8.

The above embodiment operates as follows. First, a description will be given of the closing operation in which the shut-off state shown in FIG. 1 shifts to the closing state shown in FIG. 2.

When a closing command is input to the operating mechanism 17, the insulating rod 18 and the operating rod 1 move to the left in the figure. As a result, the cylinders 10a and the insulating rods 3 provided on the arms 4 and 5 also move to the left in the figure. As the cylinder 10a moves, the movable closing resistance contact 2 moves to the left in the figure.

On the other hand, the insulating rod 3 transmits displacement to the left in the figure to the connecting link 6. Since the connecting link 6 and the insulating link 7 move in opposite directions at the same angular velocity, the connecting link 6 moves to the left in the figure, and the insulating link 7 rotates to the right in the figure. Therefore, the cylinder 10b held by the insulating link 7 and the fixed closing resistance contact 8 also move rightward in the figure.

As a result, the movable side closing resistance contact 2 and the fixed side closing resistance contact 8 come into contact and perform a closing operation. During this operation, both the closing resistance contacts 2 and 8 move closer to each other, so the speed at which the two closing resistance contacts 2 and 8 approach each other is faster than the speed at which the two electrodes 12 and 15 having the main contacts approach each other. Therefore, the insulation deterioration rate of both closing resistance contacts 2, 8 can greatly exceed that of the main contact. As a result, the closing operation of the closing resistor contacts 2 and 8 can be performed at an earlier timing than the closing operation of the main contacts.

[0027] When the closing operation is performed, the closing resistor 1
9 and 20 are inserted into the system. Then, the closing operation progresses, the springs 11 in the cylinders 10a, 10b are compressed, and both closing resistance contacts 2, 8 are wiped. After that, the closing operation further progresses, and when the main contact between the movable side electrode 12 and the fixed side electrode 15 performs the closing operation, the closing resistors 19 and 20 are short-circuited, and the closing operation is completed.

Next, a description will be given of the opening operation for transitioning from the state shown in FIG. 2 to the state shown in FIG. 1.

When the opening command is input to the operating mechanism 17, the insulating rod 18, the operating rod 1, the cylinder 10a, the insulating rod 3, and the movable closing resistance contact 2 move toward the right in the figure, contrary to the above-mentioned closing operation. Move to.

On the other hand, since the insulating rod 3 transmits the displacement to the right in the figure to the connecting link 6, the link 6 rotates in the right direction in the figure, and the insulating link 7 rotates in the left direction in the figure. Therefore, the cylinder 10b held by the insulating link 7 and the fixed closing resistance contact 8 also move to the left in the figure.

As a result, the movable side closing resistance contact 2 and the fixed side closing resistance contact 8 perform an opening operation. During this operation, both the closing resistance contacts 2 and 8 move away from each other, so the speed at which the two closing resistance contacts 2 and 8 are separated is faster than the speed at which the electrodes 12 and 15 having the main contacts are separated. Therefore, the insulation recovery speed of the closing resistance contacts 2 and 8 can exceed that of the main contact, and insulation recovery is performed on the closing resistance contacts 2 and 8 side before the main contact side. Therefore, there is no possibility that re-ignition will occur on the closing resistance contacts 2 and 8 side.

Furthermore, the movable side closing resistance contact 2 and the fixed side closing resistance contact 8 are wiped by the spring 11, but the opening speed is so fast that the spring 11 cannot follow it, and the spring 11 is compressed within the cylinders 10a and 10b. It will open up as it is. Then, at the end of the opening operation, the spring 11 is fully extended to its original state, and both closing resistance contacts 2 and 8 are pushed out to return to their closing positions.

According to this embodiment as described above, even if the breaking capacity per circuit breaker increases and the number of series breaking points decreases, the insulation recovery speed of the closing resistance contact during opening operation decreases. Therefore, excellent insulation recovery characteristics can be maintained and re-ignition at the closing resistance contacts 2 and 8 can be prevented. Further, since a sufficient time for inserting the closing resistor during the closing operation can be ensured, it is possible to reliably suppress closing overvoltage.

It should be noted that the present invention is not limited to the above-mentioned embodiment, but also includes, for example, a circuit breaker with a closing resistor in which the link mechanism section has a configuration as shown in FIG. That is, in the embodiment shown in FIG. 3, the metal holding link 21 that holds the fixed side closing resistance contact and the connecting link
A link mechanism section is constituted by these, and an attachment section for attaching this link mechanism section to the stationary side electrode 15 is an insulating section 20. In this embodiment, the fixed side closing resistance contact 8 and the fixed side electrode 15 are electrically insulated by the insulating part 20.

[0035]

As described above, according to the present invention, a movable side closing resistance contact is provided on the movable side electrode, and a link having a connecting link and a holding link that operate at the same angular velocity in opposite directions to the fixed side electrode. By providing a mechanism section, connecting an insulating rod to the connecting link to transmit the displacement of the movable side electrode to the link mechanism section, and holding the fixed side closing resistance contact on the holding link, the movable side closing resistance contact and the fixed side closing resistance are connected. Since the contacts move in opposite directions, the breaking capacity per circuit breaker increases, and even if the number of series breaking points decreases, the closing overvoltage can be ensured by ensuring sufficient time to insert the closing resistor during the closing operation. Moreover, during the opening operation, the insulation recovery speed of the making resistance contact can be prevented from decreasing and the insulation recovery characteristics can be maintained, so that re-ignition on the making resistance contact side is not caused.

[Brief explanation of the drawing]

FIG. 1 is a side cross-sectional view showing an embodiment of a circuit breaker with closing resistance according to the present invention in a disconnected state.

FIG. 2 is a side sectional view showing the closing state of an embodiment of the circuit breaker with closing resistance according to the present invention.

FIG. 3 is a side cross-sectional view showing another embodiment of the circuit breaker with closing resistance according to the present invention in a disconnected state.

FIG. 4 is a side sectional view showing a conventional circuit breaker with closing resistance in a disconnected state.

[Explanation of symbols]

1 Operating rod 2 Movable side closing resistance contact 3
Insulating rod 6 Connecting link 7 Insulating link 8 Fixed side closing resistance contact 12
Movable side electrode 15 Fixed side electrode 16 Tanks 19, 20 Closing resistor

Claims (1)

[Claims] [Claim 1] In a tank filled with insulating gas,
A circuit breaker that houses a fixed side electrode each having a main contact and a movable side electrode that can freely approach and separate from the fixed side electrode, and is provided with an operating rod that drives the movable side electrode in the closing operation direction and the opening operation direction. In this, the movable side electrode is provided with a movable side closing resistance contact that is electrically connected in parallel with the main contact, and an insulating rod that transmits the displacement of the movable side electrode, and the fixed side electrode is provided with A link mechanism section including a connecting link and a holding link that operate at the same angular velocity in the direction of A fixed side closing resistance contact is held opposite to the movable side closing resistance contact and electrically connected in parallel with the main contact, and the main contact is provided in the gap between the fixed side electrode and the fixed side closing resistance contact. A circuit breaker with a closing resistor, characterized in that it is provided with a closing resistor that suppresses a closing overvoltage that occurs during operation.