KR20220006651A - Multiphase selector-preselector device for on-load tap-changers - Google Patents

Abstract

A multi-phase selector-preselector device (10) for an on-load tap-changer comprises: an insulating tube (100) surrounding an insulating section (110); a preselector 200 disposed along the outer wall of the insulating tube; A selector device (300) disposed inside an insulating compartment and comprising a first selector arm (310) and a second selector arm (320), wherein the first selector arm (310) comprises a respective phase (L1, L2, L3) ) an odd number of moving contact elements 315-1, 315-2, 315-3, and the second selector arm 320 includes an even number of moving contact elements 325 for each phase L1, L2, L3. the selector device (300) comprising -1, 325-2, 325-3); and a drive mechanism 400 for actuating the selector device 300 , a mounting element commonly mounted such that the first selector arm 310 and the second selector arm 320 are moved in common by the drive mechanism 400 . and the drive mechanism 400 , including 410 .

Description

Multiphase selector-preselector device for on-load tap-changers

The present invention relates to a multiphase selector-preselector for an on-load tap-changer.

The on-load tap-changer is part of the power transformer and is used to switch the tapping of the transformer to regulate the output high voltage when the power transformer is in full operation, i.e., in the on-load condition. With the use of an on-load tap-changer, the output power or power supply need not be interrupted, resulting in a substantially continuous supply of output power even when the output voltage has to be regulated. The tap-changer includes a set of fixed contacts, each fixed contact connectable to a plurality of taps of a regulating winding of the power transformer. By selecting the taps to be connected or disconnected as needed, the output voltage of the transformer can be adjusted. A typical on-load tap-changer has a configuration for simultaneously changing the tapping of multiple phases, eg three phases, in a star connection configuration of the transformer windings.

A known construction of an on-load tap-changer comprises a multiphase selector-preselector arrangement in which an insulating tube surrounds an insulating compartment. The selector device of the selector-preselector arrangement is installed inside the insulating tube. The preselector device of the selector-preselector arrangement is mounted on the outer wall of the tube, ie next to the tube.

There are known selector devices comprising vertical insulated bars or selector arms for selectively bridging fixed contact rings mounted on a tube to select a desired tapping. For example, document BG 112740 A describes a selector device having two selector arms for selecting an even number of electrically fixed contacts or an odd number of electrically fixed contacts, respectively. The two selector arms are arranged separately from one another and operate independently of one another. Therefore, while synchronization of the individual movements of the selector arms is complicated in the conventional system, the configuration takes up a lot of space.

Accordingly, there is a need for a selector-preselector device that is compact and/or provides easy synchronization of the movement of the selector arms.

According to one aspect, a multiphase selector-preselector device for an on-load tap-changer is provided. The apparatus includes an insulating tube, a preselector, a selector device, and a drive mechanism. An insulating tube surrounds the insulating compartment. The preselector is disposed along the outer wall of the insulating tube. The selector device is disposed within the insulating compartment and includes a first selector arm and a second selector arm. The first selector arm includes an odd number of moving contact elements for each phase. The second selector arm includes an even number of moving contact elements for each phase. The drive mechanism is configured to actuate the selector device. The drive mechanism includes a mounting element commonly mounted such that the first selector arm and the second selector arm are moved in common by the drive mechanism.

Typically, the mounting element is configured to provide a direct mechanical link between the mounted first selector arm and the mounted second selector arm. Direct mechanical links are typically free from any gearing, pivot members, joint members, and the like. In embodiments, the mounting element is a one-piece member, preferably a one-piece metal member.

By common movement through the intermediary of the mounting member, the first selector arm and the second selector arm can be mounted close to each other, so that a compact configuration is possible.

Typically, but without limitation, the device has a three-phase configuration. Accordingly, the first selector arm includes a first phase even numbered contact element, a second phase even numbered contact element, and a third phase even numbered contact element. Likewise, the second selector arm includes a first phase odd numbered contact element, a second phase odd numbered contact element, and a third phase odd numbered contact element.

According to another aspect, an on-load tap-changer is provided. The on-load tap-changer comprises a multiphase selector-preselector arrangement as described above.

According to another aspect, a power transformer is provided. The power transformer includes an on-load tap-changer. The on-load tap-changer comprises a multiphase selector-preselector arrangement as described above.

Additional embodiments and aspects are apparent from the detailed description and dependent claims.

In embodiments, the first selector arm and the second selector arm are mounted side-by-side to the mounting element. Unlike conventional configurations in which multiple selector arms are typically mounted to be positioned at substantially opposite locations on the perimeter, this configuration using a side-by-side arrangement of two selector arms facilitates particularly having a compact and relatively rigid mounting element. , which further improves compactness and synchronization.

In other embodiments, the drive mechanism further comprises a spring energy accumulator for providing the rotational action.

In other embodiments, the first selector arm and the second selector arm are arranged such that they each extend from top to bottom along an outer surface of the selector device.

In other embodiments, the drive mechanism comprises a Geneva drive. The Geneva drive is configured to advance the selector positions of the first selector arm and the second selector arm in a stepwise manner. For example and without limitation, a Geneva drive advances the selector position by rotating, for example in 8 or more positions, typically 10 or 12 positions. According to this embodiment, in a particular configuration, the Geneva drive comprises a Geneva gear and an input shaft. The input shaft is configured to drive the Geneva gear so that the selector positions of the first and second selector arms are advanced.

In other embodiments, one of the first selector arm and the second selector arm comprises a common moving contact element or common terminal for each phase. In the example non-limiting three-phase configuration mentioned above, each of the first selector arm and the second selector arm is a first phase common moving contact element, a second phase common moving contact element, and a third phase common moving contact element. includes

Each of the even number of moving contact elements, the odd number of moving contact elements and the common moving contact elements may have a contact bridge structure. All contact bridges may be configured to form a connection between a fixed terminal, for example a fixed terminal ring disposed on the diverter switch, and a fixed output contact of the selector fastened inside the insulating compartment.

In embodiments, the apparatus further comprises a diverter switch having a fixed terminal. Each contact element is configured to establish electrical contact with a corresponding one of the fixed terminals according to a selector position of the first selector arm and the second selector arm.

In embodiments, a multiphase selector-preselector device (referred to as device for short) may have one or more of the following advantages: The device uses a simple and compact design, which allows simultaneous use of the even and odd arms of the selector. allow to run The drive of the two arms of the selector is driven by one and the same Geneva gear. Easy installation and disassembly of the device in the oil compartment of the on-load tap-changer, abbreviated as OLTC, is possible.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings.

1 is a schematic perspective view of a selector device of a selector-preselector apparatus according to an embodiment;
FIG. 2 is a schematic perspective view of the selector device of FIG. 1 viewed from another viewing angle;
3 is a schematic perspective view of a selector-preselector device according to an embodiment;
FIG. 4 is a schematic partial perspective view of the selector-preselector device of FIG. 3 ;
5 is a schematic perspective view of a preselector;
6 is a cross-sectional plan view of a drive mechanism used in a selector-preselector device according to an embodiment;
7 is a cross-sectional plan view of a selector-preselector device according to an embodiment.

1 is a perspective view of a selector device 300 of a selector-preselector apparatus 10 according to an embodiment of the present invention. 2 shows the selector device 300 as viewed from another viewing angle. The following description refers to FIGS. 1 and 2 together for convenience of description.

The column-type selector device 300 of the embodiment shown in FIGS. 1 and 2 has a three-phase configuration, that is, synchronous tapping of the first phase (L1), the second phase (L2) and the third phase (L3) formed and configured to perform selection. In the configuration shown, the diverter switch 500 resulting from the arrangement is arranged radially inside the column of the selector device 300 . The diverter switch 500 has a fixed terminal at which contact with the selector 300 is to be selected.

The first selector arm 310 and the second selector arm 320 are arranged side by side, each extending from an upper side of the selector device 300 to a lower side of the selector device 300 . The first and second selector arms 310 , 320 are made of an insulating material, ie the first and second selector arms 310 , 320 are each configured as insulating bars.

The first selector arm 310 has a first phase (L1) odd number of moving contact elements 315-1, a second phase (L2) odd number of moving contact elements 315-2 and a third phase (L3) odd number of moving contact elements. A moving contact element is arranged. Likewise, the second selector arm 320 has a first phase (L1) even number of moving contact elements 325-1, a second phase (L2) even number of moving contact elements 325-2, and a third phase (L3). ) an even number of moving contact elements 325 - 3 are arranged. The moving contact elements 315-1, 315-2, 315-3; 325-1, 325-2, 325-3 have a contact bridge configuration. During assembly of the selector device 300 , both the insulating bars 310 , 320 (the first selector arm 310 , the second selector arm 320 ) are connected to a moving contact element 315-1 with a stationary contact counterpart; 315-2, 315-3; 325-1, 325-2, 325-3) rotated by a prescribed angle to ensure proper passover

1 and 2 , odd number of moving contact elements 315 - 1 , 315 - 2 , 315 - 3 provided in first selector arm 310 and even number of moving contact elements 315 - 1 provided in second selector arm 320 In addition to the moving contact elements 325-1, 325-2, 325-3 of the first selector arm 310, a first phase (L1) common moving contact element 316-1, a second phase (L2) A common moving contact element 316-2 and a third phase L3 common moving contact element 316-3 are provided. In a particular embodiment not shown in the figure, a first phase (L1) common moving contact element, a second phase (L2) common moving contact element, and a third phase (L3) common moving contact element to the second selector arm 320 Elements may also be provided.

The first selector arm 310 and the second selector arm 320 are mounted to a mounting element 410 that is coupled to a drive mechanism 400 . The mounting element 410 is attached directly to the Geneva gear 450 . The mounting element 410 is made of steel. The mounting element 410 is attached to the first and second selector arms 310 , 320 by two metal joints. The mounting state of the first and second selector arms 310, 320 is a common mounting state, that is, the selector positions of the first and second selector arms 310, 320 are controlled in common, and the mounting element 410 is the first and there are no joints, gears, etc. between the second selector arms 310 , 320 . Thus, in the tap selection process, the first and second selector arms 310 , 320 rotate about a central axis. The mounting element 410 may also be referred to as a selector frame, which has two insulating bars (odd and even), a first selector arm 310 and a second selector arm 320 . The shape of the selector arms 310 and 320 is an elongate insulating cylinder arranged parallel to each other. Selector arms 310 and 320 have three pairs of holes, one per phase for installation of moving contact elements 315-1, 315-2, 315-3; 325-1, 325-2, 325-3.

Drive mechanism 400 typically includes a spring energy accumulator for providing rotational action. 6 , in the embodiment, the drive mechanism 400 includes a Geneva gear 450 and an input shaft 460 . The selector frame is driven by a Geneva gear 450 . And, the Geneva gear 450 is driven by the input shaft 460 . The Geneva gear 450 and the input shaft 460 form a Geneva drive that advances the selector positions of the first selector arm 310 and the second selector arm 320 in a stepwise manner.

In the perspective view of FIG. 3 , a selector-preselector device 10 according to an embodiment is shown. A partial detail view of the selector-preselector device 10 is shown in FIG. 4 . The selector-preselector device 10 comprises an insulating tube 100 surrounding an insulating compartment 110 . The insulating tube 100 is made of an insulating material such as glass fiber. The insulating tube 100 provides the mechanical structure and rigidity of the selector-preselector device 10 . The insulating tube 100 is fastened to the drive mechanism 400 by bolts. Typically, the insulating compartment 110 includes a charge of insulating oil. Inside the insulating compartment 110 , the selector device 300 is arranged. The insulating section 110 separates the insulating oil of the active part of the transformer from the insulating oil of the selector device 300 . The insulating compartment 110 is oil tight. On the outer peripheral side of the insulating tube 100, the preselector 200 in the form of an insulating bar is arranged to extend along the outer wall of the tube. The preselector 200 is attached to the housing of the drive mechanism 400 . The preselector 200 is configured to provide a rotational action driven by the drive mechanism 400 . The preselector 200 is shown separately in the perspective view of FIG. 5 . The preselector 200 includes a first phase (L1) preselector contact 210-1, a second phase (L2) preselector contact 210-2, and a third phase (L3) preselector contact 210-3 includes

As is apparent from the cross-sectional plan view of FIG. 7 , the first selector arm 310 and the second selector arm 320 are mounted side by side. The preselector 200 extends substantially parallel to the extending directions of the first selector arm 310 and the second selector arm 320 .

Although the above description refers to specific embodiments, one skilled in the art will recognize that one or more features may be suitably combined and/or that the features described herein may be suitably combined without departing from the gist of the application, which is defined in scope by the claims. It will be appreciated that it may be modified or omitted as appropriate.

Claims (11)

A multiphase selector-preselector device (10) for an on-load tap-changer, comprising:
an insulating tube 100 surrounding the insulating compartment 110 ;
a preselector 200 disposed along an outer wall of the insulating tube;
A selector device (300) disposed inside the insulating compartment and comprising a first selector arm (310) and a second selector arm (320), wherein the first selector arm (310) comprises each of the phases (L1, L2) , L3) an odd number of moving contact elements 315-1, 315-2, 315-3, wherein the second selector arm 320 has an even number of moving contact elements per each phase L1, L2, L3. the selector device (300) comprising an element (325-1, 325-2, 325-3); and
a drive mechanism (400) for actuating the selector device (300), wherein the first selector arm (310) and the second selector arm (320) are coupled to the drive mechanism (400) the drive mechanism (400) comprising a mounting element (410) to which the first selector arm and the second selector arm are commonly mounted to be moved in common by a spring energy accumulator for providing a rotational action
A multi-phase selector-preselector device (10) for an on-load tap-changer comprising a. The method of claim 1,
and the first selector arm (310) and the second selector arm (320) are mounted side by side on the mounting element (410). 3. The method of claim 1 or 2,
a multi-phase selector-preselector device for an on-load tap-changer, wherein the first selector arm (310) and the second selector arm (320) are arranged to extend from upper side to lower side along an outer surface of the selector device (300); 10). 4. The method according to any one of claims 1 to 3,
The drive mechanism (400) comprises a Geneva drive (450, 460) configured to advance the selector position of the first selector arm (310) and the second selector arm (320) in a stepwise manner. Multi-phase selector-preselector device for equipment (10). 5. The method of claim 4,
The Geneva drive includes a Geneva gear 450 and an input shaft 460, the input shaft 460 driving the Geneva gear 450 to drive the first selector arm 310 and the second selector arm ( A multiphase selector-preselector device (10) for an on-load tap-changer, configured to advance the selector position of 320). 6. The method according to any one of claims 1 to 5,
wherein one of the first selector arm (310) and the second selector arm (320) comprises a common contact element (316-1, 316-2, 316-3), a multiphase selector-free for on-load tap-changer Selector device (10). 6. The method of claim 5,
Each of the first selector arm 310 and the second selector arm 320 includes a common moving contact element 316-1, 316-2, 316-3 for each phase L1, L2, L3 , multi-phase selector-preselector device for on-load tap-changers (10). 8. The method according to any one of claims 1 to 7,
The multi-phase selector-preselector device further comprises a diverter switch 500 having fixed terminals, each of the contact elements 315-1, 315-2, 315-3; 325-1, 325-2, 325 -3; 316-1, 316-2, 316-3) make electrical contact with a corresponding one of the fixed terminals according to the selector position of the first selector arm 310 and the second selector arm 320 A multiphase selector-preselector device (10) for an on-load tap-changer, configured to establish. 9. The method according to any one of claims 1 to 8,
The multi-phase selector-preselector device (10) for an on-load tap-changer, wherein the mounting element (410) is designed as a one-piece member. 10. An on-load tap-changer comprising a multiphase selector-preselector arrangement (10) according to any one of the preceding claims. A power transformer comprising an on-load tap-changer, comprising:
10. Power transformer, wherein the on-load tap-changer comprises a multiphase selector-preselector arrangement (10) according to any one of the preceding claims.

Images