JPS6352413B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in the operating characteristics of parallel resistors and disconnectors, particularly parallel resistors and disconnectors.

It is known that a power shield breaker is equipped with a parallel resistor and used to suppress surge voltage when power is turned on or to suppress re-electromotive voltage when power is turned off.

In general, the optimum resistance value for suppressing surge surge and the resistance value for suppressing restart voltage are not necessarily equal.
Depending on the line conditions and the characteristics of the re-electromotive voltage waveform to be suppressed, the same resistor can be used both as the closing resistance and as the breaking resistance. (For example, Utility Model Publication No. 43-19705).

However, using a parallel resistor for both turning on and off has the following problems due to the difference in purpose.

FIG. 1 is a configuration diagram of a parallel resistor and a disconnection section.

Figure 2 shows the main contact closing/closing operation.
The main shield section stroke characteristics X, the opening/closing characteristics of the main contact S ₁ and the resistance contact S ₂ are shown.

In the closing operation, the resistance contact S ₂ needs to be closed at that point because the optimal closing condition exists at t ₁ ms (for example, 8 ms) before the closing of the main contact S ₁ .

On the other hand, in the shearing operation, the resistance contact S ₂ must open after the main contact S ₁ has completed shearing. Therefore, when a parallel resistor is used for both closing and disconnecting, the operating characteristics of the resistance contact S ₂ for closing and disconnecting are as follows for the main contact S ₁
This requires characteristics different from the operating characteristics of .

Also, when using the parallel resistor R as a shear resistance, as mentioned above, after the main contact S ₁ has been sheared,
Resistance contact S ₂ must be opened. In the unlikely event that the resistance contact S ₁ is opened before the main contact S ₁ is completely disconnected, there is a possibility that the main contact S ₁ cannot be disconnected.

Under these conditions, the main contact S ₁ and the resistive contact
In a structure where S ₂ is mechanically connected, under an accident condition where the shearing time is short, and therefore the shearing operation is completed in the first half of the shearing operation stroke, the resistance contact S ₂ and the main contact S Change lever ratio of ₁ (for example,
19582), the above-mentioned operation sequence can be set relatively easily. However, in a puffer-type gas shield breaker, etc., which increases the puffer pressure by the shielding action, it is difficult to set the operation sequence at the time of asymmetrical current Under the most severe conditions, the shearing time may extend to the latter half of the shearing operation process.

Resistance contacts with no problems under these conditions
As shown in FIG. ₂ , the opening of S 2 begins when the main contact S ₁ completes its opening operation.

However, in the mechanically connected configuration described above, upon completion of the operation of the main contact S ₁ , the resistance contact S ₁
The operation of the resistive contact is also completed, so it is difficult to realize the ideal operation of the resistive contact described above.

Further, it is not preferable to operate the resistance contact and the main contact by separate drive systems because the structure becomes complicated.

The object of the present invention is to open the resistor and disconnection mainly after the disconnection operation is completed, while keeping the setting of the resistor ON timing of the parallel resistor and disconnector at the optimum position. An object of the present invention is to provide a disconnector with a parallel resistor that can always maintain the disconnection at an optimum condition.

The main point of the present invention is that the advance insertion of the parallel resistance shield and the disconnection part is performed by the difference in the lever ratio of the link mechanism,
On the other hand, the parallel resistance shield section can be opened by releasing the locked state of the spring stored during the closing operation, and by pulling out the hook immediately before the completion of the shielding operation of the main shield section. This should be done when the main contact has completed its breaking operation.

Embodiments of the present invention will be described below with reference to FIGS. 3 to 7.

FIG. 3 shows the open state of the parallel resistor and disconnection section to which the present invention is applied.

In FIG. 3, the main sheath section consists of a main stationary contact 1 and a main movable contact 2 which is connected to the other end of a link mechanism 9 part which connects one end to the operating rod 10 and is driven as will be described later. . The resistance sheath disconnection includes a resistor 3, a fixed resistance contact 4, a movable resistance contact 5, a spring 6 biasing the resistance movable contact 5 in the opening direction, and a resistance movable contact 5. A hook 7 that holds the hook in the closing direction, and a lever mechanism 8 that pulls out the hook 7
It is equipped with a link mechanism 9 that drives the resistance movable contact 5, the lever mechanism 8, and the main movable contact 2;
An operating rod 10 and the like are provided which connect the link mechanism 9 to an operating device (not shown). The link mechanism 9 includes a short lever portion 9A that connects with the main movable contact 2.
and a long lever portion 9 that drives the movable contactor 5 for resistance.
The lengths of the short lever part 9A and the long lever part 9B are appropriately set to a lever ratio so that the function of the parallel resistor-equipped shield and breaker can be maintained at an optimum condition.

The operation will be explained using FIG. 4 and subsequent figures.

In response to the closing command, the operating rod 10 is pushed upward, and the link mechanism 9 is rotated clockwise.
Accordingly, both the main movable contact 2 and the fixed movable contact 5 are driven in the closing direction.

In this operation, the difference in length between the short lever part 9A and the long lever part 9B in the link mechanism 9,
In other words, due to the difference in lever ratio, as shown in FIG.
advance injection will be made.

After that, as shown in FIG. 5, the main movable contact 2
and the main fixed contact 1 are closed, completing the closing operation. Upon completion of the closing operation, the hook 7 engages with the engagement mechanism 11 of the movable resistance contact 5, thereby
Holds the resistive contact in the closed position.

In the shearing operation shown in Fig. 6, the operating rod 10
When is driven downward, the link mechanism 9 rotates counterclockwise, and the main movable contact 2 and the main fixed contact 1 are opened, but the resistance movable contact 5 is held by the hook 7 and remains in a closed state. It remains as it is.

As shown in FIG. 7, just before the shearing operation is completed, the link mechanism 9 pushes one end of the lever mechanism 8, the hook 7 is released, and the movable resistance contact 5 is wiped by the force of the biased spring 6. Opens after operation.

By adjusting the position where the link mechanism 9 pulls out the hook 7 and the wipe stroke, the opening of the resistance contact can be set after the main contact has completed the cutting operation.

As described above, according to the present invention, it is possible to set the opening/closing operation of the parallel resistor and disconnector of the parallel resistor and disconnector to optimal conditions for both closing and disconnection.

[Brief explanation of drawings]

Figures 1 and 2 are block diagrams of resistors and disconnectors and sequence diagrams of each contact, and Figures 3 to 7 are schematic diagrams of parallel resistors and disconnectors according to an embodiment of the present invention. It is. 1... Main fixed contact, 2... Main movable contact, 3
...Resistor, 4... Fixed contact for resistance, 5... Movable contact for resistance, 6... Spring, 7... Hook, 8
... Lever mechanism, 9 ... Link mechanism, 9A ... Short lever section, 9B ... Long lever section, 10 ... Operation rod, 11 ... Engagement mechanism.

Claims (1)

[Claims] 1 A resistor sheath section having a resistor, a fixed contact for resistance, and a movable contact for resistance is provided electrically in parallel with a main sheath section having a main fixed contact and a main movable contact, and the resistor The main shield section closes the circuit before the main shaft section and opens after the main shield section completes the shielding operation, and the above-mentioned resistance movable contact and main movable contact are They are each operated by a link mechanism connected to the operating rod, and the link mechanism includes a short lever section for operating the main movable contact and a long lever section for operating the resistance movable contact. A spring is provided which closes the resistor and the disconnection prior to the resistor, and a spring is provided which is energized as an opening force of the resistor and the disconnection by the closing operation of the resistance movable contact. A part of the shield is engaged with a hook connected at one end to a lever mechanism operated by a link mechanism to lock the movable resistance contact in the closing position, and also to lock the main shield in the closing position. A shiya disconnector characterized by having an engagement mechanism that releases the lock before the lock is completed.