JPH06267768A - On-load tap changer - Google Patents

Abstract

PURPOSE:To realize improvement of energization capacity and compactness of a structure. CONSTITUTION:In a loaded tap switching device provided with a contact device consisting of movable contacts which are in contact with each other with upper and lower surfaces of a plurality of fixed contacts 4 arranged in an outer periphery of a tap selector and a collector ring 3 attached to an inner peripheral side thereof therebetween, and select the fixed contact 4 by driving of a driving source and energize a space between it and the collector ring 3, a plurality of roller-like contacts 5a, 5b, 5c are arranged horizontally and radially as a movable contact. A partition 9 is provided between the roller-like contacts to make possible horizontal circumferential operation of each roller-like contact, and the roller-like contact is attached to a holding case 6 through a wipe spring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load tap changer for a transformer, and more particularly to a load tap changer having an improved structure of a contact device for energizing a tap selector.

[0002]

2. Description of the Related Art A load tap changer (hereinafter abbreviated as LTC) attached to a transformer is for adjusting a voltage by switching a tap provided on a transformer winding while the transformer is operating. The LTC is roughly divided into a switching switch and a tap selector.

FIG. 3 shows an example of the structure of such a conventional LTC. Reference numeral 1 is a switching switch, and 2 is a tap selector for selecting a tap provided on a winding of a transformer 10. Switching switch 1
Has a role of switching the circuit by opening and closing the load current when switching the taps, and the tap selector 2 has a pair of movable contacts for energization, one of which is always energized, and the other of which is a fixed contact in the unloaded state. Is selected, and the movable contact on the unloaded side precedes the switching switch 1 and plays a role of selecting the next required tap position.

In this case, the contact device used for the tap selector 2 is in direct contact with the insulating oil in the transformer tank, is functionally energized only at the normal stop position, and is moving for tap selection. When not energized.

In the conventional LTC, the contact device used in the tap selector 2 has a circle on the same plane as the fixed current collecting ring 3 as a contact common to all the taps as shown in FIG. A pair of upper and lower movable contacts 5, which come into contact with the fixed contact 4 arranged around the circumference and the current collecting ring 3 to energize or sequentially move to another adjacent fixed contact (not shown).
The movable contacts 5 and 5'are provided by being held by a holding case 6 which is moved by a required angle as required, and the wiping springs 7 and 7'applying contact pressure to the movable contacts 5 and 5 '. It is supported by the support pin 8 via.

[0006]

However, in such a conventional contact device, a pair of upper and lower movable contacts 5 are provided.
In the case of energizing only with 5 ', the energizing capacity is limited due to the limitation of the energizing area, and in order to improve this, there is a restriction from the structural aspect simply by enlarging the shape. Therefore, when it is applied for a large current, there are problems in improving the current carrying capacity and making the structure compact.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a load tap changer capable of improving the current carrying capacity and downsizing the structure.

[0008]

In order to achieve the above object, the present invention sandwiches a plurality of fixed contacts arranged on the outer circumference of a tap selector and an upper and lower surface of a current collecting ring mounted on the inner circumference side. A load contact tap changer including a contact device that is in contact with each other and is driven by a drive source to select the fixed contact to energize between the fixed ring and the current collecting ring. As the above, a plurality of roller-shaped contacts are arranged horizontally and radially so as to be independently operable, and these roller-shaped contacts are attached to the holding case via wipe springs.

Further, a plurality of roller-shaped contacts are arranged radially as movable contacts, and a partition plate is provided between these roller-shaped contacts so that the roller-shaped contacts can move in the horizontal direction. The roller-shaped contactor is provided and attached to the holding case via a wiping spring.

[0010]

In the load tap changer having such a structure, a plurality of horizontal and radial roller-shaped contacts which are in contact with the fixed contact and the current collecting ring of the tap changer are independently provided. Since each contactor operates and divides the passing current while making an optimum contact, a large current can be conducted even if each contactor is small, and a compact contact can be obtained.

Further, the individual roller-shaped contacts are arranged via a partition plate so as to be radial with respect to the drive source,
Moreover, since it is supported by the wiping spring provided independently from the holding case, all the roller-shaped contacts smoothly operate in the same direction in the horizontal circumferential direction, and it is possible to form a contact having a small driving torque.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the structure of a contact device in which an LTC tap selector is horizontally sectioned. The same components as those in FIG. 4 are designated by the same reference numerals. As shown in Figure 1,
By the fixed contact 4 arranged on the outer circumference of the tap selector, the current collecting ring 3 provided on the inner circumference side so as to face the fixed contact 4 and circulate, and the rotation driving unit at the center of the tap selector. It is composed of movable contacts 5 and 5 ′ that are driven and bridge between the fixed contact 4 and the current collecting ring 3, and a holding case 6 that houses these movable contacts 5 and 5 ′.

A plurality of movable contacts 5 and 5'are provided on the upper and lower surfaces of the fixed contact 4 and the current collecting ring 3, and in this example, three roller contacts 5a, 5b, 5c and 5a ', 5b', respectively. 5c
′ Is horizontally arranged and can be independently operated radially with respect to the drive source, and a partition plate 9 made of an insulating material is provided between the respective roller-shaped contacts to partition the ‘
As shown in FIG. 2, each roller contact 5a, 5b, 5c and 5
A wiping spring 7 is attached between a ', 5b', 5c 'and the holding case 6. In this case, all the roller-shaped contacts 5a, 5b, 5c, 5a ',
5b 'and 5c' can be operated in the same horizontal direction.

In the contact device of the tap selector in the LTC having such a structure, roller-shaped contacts 5a, 5b, 5c, 5a ', 5b', which constitute the movable contacts 5, 5 ',
It is assumed that 5c 'is stopped at the normal position and is energized as shown in FIGS. In this case, the movable contacts 5, 5'can operate independently in the horizontal direction, and a total of 6 wipe springs 7 are individually attached.
Individual roller contacts 5a, 5b, 5c and 5a ', 5b
′ And 5c ′ are in optimal contact at each independent position.

Therefore, the energizing current is applied to each roller contact 5
6 through a, 5b, 5c and 5a ', 5b', 5c '
In order to divide the flow, the individual roller-shaped contacts 5a, 5b, 5
Even if c, 5a ', 5b', 5c 'is small, a large current can be passed.

When the movable contact moves to the adjacent fixed contact, first, when the holding case 6 is driven, the upper and lower three roller-shaped contacts 5a, 5 are arranged horizontally.
b, 5c and 5a ', 5b', 5c 'are transmitted to the roller-like contacts (for example, 5a, 5a') on the outer side in the reaction direction, and the partition plate 9 is provided between the roller-like contacts.
Another roller contact (for example, 5b, 5
c, 5b ', 5c'), the entire movable contact operates. In this case, since the roller contacts 5a, 5b, 5c and 5a ', 5b', 5c 'are radially arranged with respect to the drive source, smooth movement is achieved.

Therefore, since each roller-shaped contactor can be operated individually, it moves independently depending on the shape of the contact portion of the fixed contact, so that each roller-shaped contactor can maintain the optimum energization state. .

As described above, in this embodiment, as the movable contacts 5 and 5'which are in contact with the upper and lower surfaces of the fixed contact 4 and the current collecting ring 3 to energize them, three roller contacts 5a and 5 are provided.
Since b, 5c and 5a ', 5b', 5c 'are arranged so as to be movable in the horizontal direction and optimal contact is made at each contact position to make the energizing current flow for 6 minutes, Even if it is small, it can carry a large current, and the whole can be a compact contact.

Further, each roller-shaped contact is arranged so as to be radial with respect to the driving source, and a partition plate is provided between each roller-shaped contact so that all the roller-shaped contacts can operate in the same manner. Therefore, smooth operation is possible.

Furthermore, the individual roller contacts 5a, 5
Since the wiping springs 7 are independently mounted between the holding cases 6 and b, 5c, 5a ', 5b', 5c ', the total load is less than the case where the wiping springs are collectively provided to all the roller contacts. It is possible to obtain an LTC with a small driving torque and a small driving torque.

In the above embodiment, the case where three roller-shaped contactors are horizontally arranged radially above and below the fixed contact and the current collecting ring has been described, but other than three depending on the rated current or the structural condition. Even if it is configured as a plurality of roller-shaped contactors, the same operational effect as described above can be obtained.

[0023]

As described above, according to the present invention, a plurality of roller-shaped contacts serving as movable contacts are horizontally and radially arranged so as to be independently operable, and are independently provided between the movable case and the holding case. Since it is attached via the wipe spring provided on the main body, it can carry a large current and can be used as a compact contact, and when the load is equipped with a contact device that operates smoothly and has a small driving torque. A tap switching device can be provided.

[Brief description of drawings]

FIG. 1 is a plan view of a current-carrying contact portion, which is a horizontal cross-section of a tap changer in an embodiment of the tap changer during load according to the present invention.

FIG. 2 is a vertical sectional view showing the energizing contact device of FIG.

FIG. 3 is a configuration diagram for explaining an outline of a load tap switching device of a transformer.

FIG. 4 is a vertical sectional view showing a conventional contact device for energizing a tap changer.

[Explanation of symbols]

1 ... switching switch, 2 ... tap selector, 3 ... collector ring,
4 ... Fixed contact, 5, 5 '... Movable contact, 5a, 5b, 5
c, 5a ', 5b', 5c '... Roller-shaped contactors, 6 ... Holding case, 7 ... Wiping spring, 9 ... Partition plate.

Claims (2)

[Claims] 1. A plurality of fixed contacts arranged on the outer circumference of a tap selector and the upper and lower surfaces of a current collecting ring mounted on the inner circumference side of the tap selector are contacted with each other, and the fixed contacts are selected by driving a driving source. In a load tap changer equipped with a contact device composed of a movable contact that energizes between the contact ring and the current collecting ring, a plurality of roller-shaped contacts can be independently operated as movable contacts of the contact device. A load tap switching device characterized in that the roller-shaped contacts are horizontally and radially arranged, and each of the roller-shaped contacts is attached to a holding case via a wiping spring. 2. A plurality of fixed contacts arranged on the outer circumference of the tap selector and the upper and lower surfaces of a current collecting ring mounted on the inner circumference side are contacted with each other, and the fixed contacts are selected by driving a driving source. In a load tap changer equipped with a contact device composed of a movable contact for energizing between the current collector ring and the current collecting ring, a plurality of roller-shaped contacts are radially arranged horizontally as movable contacts of the contact device. In addition, a partition plate is provided between these roller-shaped contacts so that the roller-shaped contacts can move in the horizontal direction, and the roller-shaped contacts can be attached to the holding case via wipe springs. The tap switching device at the time of load characterized by the above.