JPH0113615B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sheath breaker having a two-stage closing resistance contact.

When the voltage becomes very high, such as ultra-super high voltage, it becomes necessary to suppress the switching surge that occurs when the circuit breaker opens and closes. In other words, at such high voltages, no matter how large the required insulation distance in the air, the dielectric strength does not increase much, which is a saturation characteristic, so in order to economically construct power transmission lines,
This is because it is desired to reduce opening/closing surges.

Since a large surge occurs in the circuit breaker when the circuit is reclosed after the circuit is disconnected, this is suppressed by inserting a resistor at the time of closing, and then closing the main contact. However, in order to further suppress the surge during closing, it is effective to adopt a two-stage closing method, in which a high resistance is inserted first, a low resistance is inserted next, and the main contact is closed last. However, this requires a contact mechanism that reliably inserts two types of resistors at a predetermined time.

Conventionally, for example, the next closing resistance circuit is connected in parallel with the main contactor. That is, a resistive contact plate,
A closing resistance circuit is constructed by connecting a resistor A of 1200Ω and a resistor B of 300Ω in series, and a resistor contact Z connected in parallel with the resistor A to short-circuit the resistor A.
And after the resistance contact Z is closed,
It is linked to the resistance contact instep so that it closes after 5ms. In such a configuration, the voltage applied between the resistive contacts Z, which is open immediately after the resistive contacts are closed at the time of turning on, is 1200/(1200+300) of the voltage previously applied between the resistive contacts. )=0.8
(times). On the other hand, since the insertion time of the total resistance (1200Ω+300Ω) is as short as 5ms, it is necessary to make the distance between the contacts of the resistance contactor Z as short as possible. Therefore, the withstand voltage value between the resistive contacts Z must be designed to be low, so when a high voltage like the one mentioned above is applied, a flash will occur between the resistive contacts Z, reducing the total resistance (1500Ω). Resistance Z immediately after insertion
There was a problem that there was a risk that the resistance would become 300Ω.

The present invention has been made in view of these points,
To provide a breaker having a simple structure, high reliability, and equipped with a contact for a two-stage closing resistance.

An embodiment of the present invention is shown in FIG. 1 below. High-voltage shield disconnectors generally use a multi-point shield disconnection method in which several shield disconnections are connected in series, and Figure 1 shows one of the shield disconnections. It is. Here, each contact point of the shingle section is shown in a completely open state.
In the figure, 1 is a frame made of a conductive material and also serves as a terminal, 2 is a support made of an insulating material that is fixed to the frame 1, and 3 is a metal fitting that is fixed to the support 2 and also serves as a terminal. A resistor 4 has one end connected to the metal fitting 3, and is fixed to the metal fitting 3. 5 is conductor 6
7 is a resistor whose one end is connected to the other end of resistor 4 via conductor 8, and 9 is a resistor whose one end is connected to the other end of resistor 7 through conductor 8. This is a resistor connected via a conductor 10. The total resistance value of both resistors 7 and 9 is greater than the total resistance value of both resistors 4 and 5. 11 is a conductor connected to the other end of the resistor 9, and 12 is a support made of an insulating member, which connects the conductor 11 and the metal fitting 3.
13 is an arc fixed contact fixed to the metal fitting 3;
4 is a movable arc contact that comes into contact with and separates from the fixed arc contact 13, and is the last part to open and generate an arc when the breaker breaks.
Arc-resistant materials such as copper-tungsten are used for the tip. 15 is a main fixed contact fixed to the metal fitting 3; 16 is a main movable contact that moves into contact with and separates from the main fixed contact 15 in conjunction with the arc movable contact 14; 17 is a main movable contact fixed to the frame 1. 16 and a sliding contact that can slide; 18 a nozzle made of an insulator such as Teflon to enable gas spraying when the beam is cut off; and 19 that drives both movable contacts 14 and 16. This is a connecting body for controlling the operating mechanism, and is connected to the operating mechanism by a connecting mechanism (not shown). 20 is a first resistance contact that is electrically connected to the conductor 11 and can be moved a predetermined distance;
It is fixed. 22 is a second resistance contact which is fixed to the main movable contact 16 and comes into contact with and separates from the first resistance contact 20; the main fixed contact 15 and the main movable contact 16;
The first resistive contact 20 is configured to be connected to the first resistance contact 20 earlier than the first resistance contact 20 and the first resistance contact 20 are connected to each other. 23 is the connecting rod 21
The sliding contact is electrically connected to the first resistance contact 20 and is connected to the conductor 11 .
24 is a spring that presses the first resistance contact 20 in the direction of the second resistance contact 22; 25 is a stopper that stops the first resistance contact 20 at a predetermined position;
A third resistance contact 6 is electrically connected to one end of the resistor 7, and is pivotally connected to the conductor 8 so as to be movable a predetermined distance. 27 is a fourth resistance contact that is pressed by the connecting rod 21 and joins with the third resistance contact 26, and is connected to the main fixed contact 15 and the main movable contact 1
6 is connected earlier than the first resistance contact 20 and the second resistance contact 22 are connected later than the first resistance contact 20 and the second resistance contact 22 are connected. 28
29 is a spring that presses the third resistance contact 26; and 30 is a stopper that stops the third resistance contact 26 at a predetermined position. be. In addition, 21, 24,
25 and 28 constitute a moving mechanism 31.

Next, the operation will be explained. In FIG. 1, a driving force is applied to the connecting body 19 from an operation mechanism (not shown), causing the main movable contact 16, the second resistance contact 22, etc. to move in the left direction. First, the second resistance contact 2
2 contacts the first resistance contact 20, and via the sliding contact 23, the current flows from each resistor 9, 7, 5, 4 to the fitting 3. In this case, each resistor 4,
The sum of the resistance values of 5, 7, and 9 is a high resistance value, such as 1500Ω, and the high resistance is first inserted into the circuit. Subsequently, the main movable contact 16 and the first resistance contacts 20 and 22 move further to the left against the spring 24, and the fourth resistance contact 27 moves against the spring 28 via the connecting rod 21. move against it,
Approximately 5 ms after the second resistive contact 22 contacts the first resistive contact 20, the fourth resistive contact 27 contacts the third resistive contact 26. In this way, the resistors 7 and 9 are short-circuited, and resistors 4 and 5 of, for example, 300Ω are inserted into the circuit.

Furthermore, each movable contactor 14, 16, 2
2 moves, the arc fixed contact 13 and the arc movable contact 14 come into contact, and the main current begins to flow.

Subsequently, the main movable contact 16 is connected to the main fixed contact 15.
The closing operation is completed when the main current flows through the contact point. Each resistance contact 20, 22, 2
6, 27, etc. also move to the final position while accumulating the springs 24, 28, 29, etc., and enter the closed state shown in FIG.

Next, the shearing operation will be explained with reference to FIG.
When a driving force is applied to the connecting body 19 from an operation mechanism (not shown) in the right direction in the drawing, which is opposite to the closing direction,
Both the main movable contact 16 and the second resistance contact 22 begin to move in the opening direction. However, at this time, the first resistance contact 20 is affected by the force of the spring 24 applied thereto, and the fourth
The force of the spring 28 applied through the resistive contact 27 of
Even if the forces are combined, an acceleration greater than the acceleration of the second movable resistance contact 22 cannot be obtained, so first, the space between the first resistance contact 20 and the second resistance contact 22 opens. Therefore, in the event of a breakdown, resistors 4, 5,
No current flows through 7 and 9.

Next, the space between the main fixed contact 15 and the main movable contact 16 is opened, and the main current flowing through them is transferred to both the arc contacts 13 and 14. Next, the arc contacts 13 and 14 are opened, and an arc is generated there. At this time, the gas in the space A surrounded by the cylinder part of the main movable contact 16 is compressed and the nozzle 1
8, the arc is blown out by the strong gas flow and the current is interrupted. Furthermore, the movable contact 16 moves in the opening direction to reach the open state shown in FIG.

On the other hand, the springs 24, 28, 29 each contact 20,
Although the force is insufficient to move the contacts 26 and 27 following the opening operation of the second resistance contact 22, these contacts 20, 26, 27 will move by the opening degree of about 300 ms when the next closing operation begins. It has sufficient force to move the terminal to a predetermined position, and before the next closing operation, each resistance contactor 20, 26, 27 also returns to the open state shown in Fig. 1 by its respective spring. .

In the above embodiment, the fourth resistance contact 27 has a lever structure with rotation support at one end, and
The movement of the fourth resistance contact 27 is expanded by making the distance to the point of contact with the connecting rod 21 connected to the resistance contact 20 of the fourth resistance contact 27 much smaller than the distance of the contact point at the tip of the fourth resistance contact 27. ing. Therefore, a movement can be made to ensure a large insulation distance between the third and fourth resistance contacts 26 and 27 in a short period of time, thereby preventing flashover between them. By this, resistors 7, 9
is inserted reliably for a predetermined period of time.

Note that the spring 29 that brings the third resistance contact 26 into contact with the fourth resistance contact 27 is applied in a direction substantially perpendicular to the moving direction of the fourth resistance contact 27. It is preferable to prevent this from acting as an accelerating force when the resistance contactor 20 is broken. For example, the third resistive contact 26 and the fourth resistive contact 2
7 are in contact with each other, the shape reduces the component force in the movement direction of the fourth resistance contact 27 as shown in Fig. 3, or the shape is perpendicular to the movement direction of the fourth resistance contact 27 as shown in Fig. 4. It is also a good idea to apply spring force from a certain direction. In this way, only the sizes of the springs 24 and 28 are related to the movement of the first resistance contact 20, making the design easier.

In the above embodiment, the resistors 4, 5, 7, and 9 are connected in series, but the resistors 4, 5, 7, and 9 are
Resistors 7, 9 having a high resistance value between them may be connected in parallel with resistors 4, 5 having a low resistance value between the third and fourth resistance contacts 26, 27, respectively.

Alternatively, a structure may be adopted in which a gap is provided between the connecting rod 21 that transmits the movement of the first resistance contact 20 and the fourth resistance contact 27 to create a time difference in operation.

According to this invention, the distance between the third and fourth resistance contacts is increased by providing a movement mechanism that makes the amount of movement of the fourth resistance contact larger than the amount of movement of the first resistance contact. Since it can be made larger, reliability can be improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
The figure is an explanatory view showing a state in which the contacts shown in FIG. 1 are joined, and FIGS. 3 and 4 are configuration diagrams showing other embodiments of the main parts of FIG. 1, respectively. In the figure,
4, 5, 7, 9 are resistors, 15 is the main fixed contact,
16 is the main movable contact; 20 and 22 are the first and second movable contacts;
, 26 and 27 are third and fourth resistance contacts, and 31 is a moving mechanism. Note that the same reference numerals in each figure indicate the same or equivalent parts.

Claims (1)

[Claims] 1 A main fixed contact, a main movable contact that comes into contact with and separates from this main fixed contact, a first resistor whose one end is connected to the main fixed contact, and whose one end is connected to the other end of the first resistor. a second resistor connected to the other end of the second resistor and movable a predetermined distance; a second resistive contact that connects with the first resistive contact earlier than the first resistive contact, a third resistive contact that is connected to the other end of the first resistor, and the first resistor. The third resistor operates in conjunction with the contact, and is earlier than the main fixed contact and the main movable contact are joined together, and later than the first resistive contact and the second resistive contact are joined. A fourth resistance contact that contacts the contact and is connected to the other end of the second resistor,
After the second resistance contact contacts the first resistance contact, the first resistance contact is pressed, and the amount of movement of the fourth resistance contact is changed from that of the first resistance contact. A shiya disconnector characterized by being provided with a movement mechanism that makes the amount of movement larger than the amount of movement.