CN203300411U - Transformer externally hung on-load tap switch - Google Patents

Abstract

The utility model discloses an on-load tap changer mounted externally on a transformer, comprising a bottom plate and a first vertical plate and a second vertical plate fixed on both sides of the bottom plate. A diverter switch and a tap selector are arranged in the formed space, and the diverter switch and tap selector are supported by the first vertical plate and the second vertical plate; The composite sheave mechanism for the action of the tap selector; several terminal posts are arranged on the bottom plate. Using the above-mentioned tap selector and diverter switch arranged parallel to the axial direction and arranged in a triangular relationship in the lateral direction can greatly increase the lateral insulation distance between each phase of the switch, and realize the design requirements of the switch for high voltage and high current, and at the same time realize The external on-load tap-changer can be adapted to the △ connection method of the transformer, so that the traditional function of three single-phase external composite on-load tap-changers to carry out the △ connection arrangement can be realized by using only one of the utility model .

Description

An on-load tap-changer mounted outside a transformer

technical field

The utility model relates to the technical field of a transformer on-load tap changer, in particular to an externally mounted on-load tap changer of a transformer.

Background technique:

The on-load tap-changer is to change the output voltage of the transformer by changing the winding taps connected to the transformer and changing the turns ratio of the primary and secondary windings of the transformer when the transformer is on-load (that is, without power failure).

In the traditional technology, the combined on-load tap-changer usually includes a diverter switch and a tap selector; the diverter switch is on the top, the tap selector is on the bottom, and the middle is mechanically connected, which is integrated into the flange hole of the transformer cover. Inside the transformer tank. The diverter switch is usually a cylindrical member, sealed in its own separate cylindrical oil chamber, and the tap selector is usually a cage structure with a number of terminals on it for corresponding connection with the transformer coil taps, directly submerged In the insulating medium of the transformer oil tank.

This structure has the following disadvantages:

The transformer needs to reserve a switch position, which increases the size of the transformer. Switch fault repair and routine maintenance are more troublesome, and the transformer needs to be drained and suspended as a whole, resulting in loss of maintenance costs and hidden dangers of accidents. If the diverter switch oil chamber leaks or is damaged, it will pollute the transformer oil, causing greater losses and hidden dangers of accidents.

Existing plug-in on-load tap-changers only have a compound type, which combines switching and selection functions, that is, the transition contacts, arc contacts, transition resistors and main contacts are combined in the moving contact assembly. On the top, through the rotation of the switch spindle, the transition and switching actions are completed at one time. Due to structural reasons, composite switches are often only suitable for low-voltage and small-capacity on-load tap-changers, and are not suitable for high-voltage and high-current requirements.

In addition, the existing combined on-load tap-changer only has a Y-type connection mode. For a large-scale △-connection transformer, three switches need to be selected, and each switch controls one of the phases, resulting in increased transformer volume, difficult wiring, and increased costs.

Utility model content

The technical problem to be solved by the utility model aims at overcoming the above-mentioned technical problems existing in the existing on-load tap-changer, and provides an on-load tap-changer mounted outside the transformer.

The technical problem to be solved by the utility model can be realized through the following technical solutions:

An on-load tap changer mounted outside a transformer, comprising a bottom plate and first vertical plates and second vertical plates fixed on both sides of the bottom plate, arranged in the space formed by the bottom plate and the first and second vertical plates There are a diverter switch and a tap selector, and the diverter switch and the tap selector are supported by the first vertical plate and the second vertical plate; the control diverter switch and the tap selector are arranged on the outside of the first vertical plate Composite sheave mechanism; several terminal posts are arranged on the bottom plate.

In a preferred embodiment of the present invention, the tap changer and the tap selector are arranged in parallel in the axial direction and arranged in a triangular relationship in the transverse direction, with the diverter switch on the top and the tap selector on the bottom.

In a preferred embodiment of the present utility model, the tap selector includes a single-group tap selector and a double-group tap selector, and the single-group tap selector and the double-group tap selector are axially Arranged in parallel and separately located on the left and right sides or the upper and lower sides of the tap changer.

In a preferred embodiment of the present utility model, the compound sheave mechanism controls the actions of the single-group tap selector, the double-group tap selector and the changeover switch and the phase relationship among their actions.

In a preferred embodiment of the present utility model, the first vertical plate and the second vertical plate are made of metal material through casting or welding.

In a preferred embodiment of the present utility model, the first vertical board and the second vertical board are molded from insulating materials.

In a preferred embodiment of the present utility model, the transition function of the tap changer is the vacuum tube contact assembly.

Since the utility model adopts the above technical scheme, compared with the prior art, it has the following significant advantages:

1. The above-mentioned tap selector and the diverter switch are arranged in parallel in the axial direction and arranged in a triangular relationship in the lateral direction, which can greatly increase the lateral insulation distance between each phase of the switch, and realize the design requirements of the switch for high voltage and high current. It realizes that the external-mounted on-load tap-changer can be adapted to the △ connection method of the transformer, so that the traditional function of three single-phase external-mounted compound on-load tap-changers to carry out the △ connection arrangement function can be realized by using only one of the utility model. can achieve.

2. The entire combined on-load tap-changer is hung outside the transformer, thereby reducing the volume of the transformer, simplifying the wiring of the winding, reducing the cost, and facilitating the maintenance of the switch. During maintenance, there is no need for transformer oil drain and hanging cover.

3. The switch oil chamber and the transformer oil tank are separated independently. If there is a problem with the switch, the transformer oil will not be polluted.

Description of drawings

The utility model will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 1 is a structural schematic diagram of an on-load tap-changer mounted outside a transformer of the present invention.

Fig. 2 is a cross-sectional schematic diagram of an on-load tap-changer mounted outside the transformer of the utility model.

Fig. 3 is a vertical diagram of an on-load tap-changer external to the transformer of the present invention.

Fig. 4 is a schematic view of the utility model transformer with an external on-load tap-changer viewed obliquely upward.

Detailed ways

In order to make the technical means, creative features, goals and effects achieved by the utility model easy to understand, the utility model will be further elaborated below in conjunction with specific illustrations.

Referring to Fig. 1 to Fig. 4, an on-load tap-changer attached to a transformer shown in the figure includes a bottom plate 100 and two vertical plates 210 and 220 fixed on both sides of the bottom plate 100, and the bottom plate 100 and two vertical A diverter switch 300 and a tap selector are arranged in the space formed by the boards 210 and 220 , and the tap selector is divided into a single-group tap selector 410 and a double-group tap selector 420 . The bottom plate 100 is used to connect with the flange on the transformer, and is hung outside the oil tank of the transformer to form a plug-in tap changer.

The diverter switch 300, the single-group tap selector 410, and the double-group tap selector 420 are supported by two vertical plates 210 and 220; the tap changer 300, the single-group tap selector 410, and the double-group tap selector The switch 420 is arranged parallel to the axial direction and arranged in a triangular relationship in the lateral direction. The upper part is the diverter switch 300 , and the lower part is the single-group tap selector 410 and the double-group tap selector 420 . The single-group tap selector 410 and the double-group tap selector 420 are respectively arranged on the left and right sides or the upper and lower sides of the lower side of the tap changer 300 .

On the outside of the vertical plate 210, there is a composite sheave mechanism 500 that controls the actions of the diverter switch and the tap selector; Actions and their phase relationship between actions.

The two vertical plates 210, 220 can be cast or welded from metal materials. It can also be formed by compression molding of insulating material.

All the terminal posts 600 in the transformer external on-load tap changer are installed on the base plate 100 to facilitate connection with the windings in the transformer. In the tap changer 300, the transition function is the vacuum tube contact assembly.

The above content shows and describes the basic principles, main features and advantages of the present utility model. Those in the industry should understand that the utility model is not limited by the above-mentioned examples. What is described in the above-mentioned examples and explanations is only to illustrate the principle of the utility model. The utility model will also have the following advantages without departing from the spirit and scope of the utility model. Various changes and improvements will fall within the scope of the claimed utility model. The scope of protection required by the utility model is defined by the appended claims and their equivalents.

Claims (7)

1. An on-load tap-changer mounted outside a transformer, characterized in that it comprises a base plate and a first vertical plate and a second vertical plate fixed on both sides of the base plate, and by the base plate and the first and second vertical plates A diverter switch and a tap selector are arranged in the space formed by the board, and the diverter switch and tap selector are supported by the first vertical plate and the second vertical plate; a control switch is arranged outside the first vertical plate Composite sheave mechanism acting with tap selector; several terminal posts are set on the bottom plate. 2. The on-load tap-changer mounted outside the transformer according to claim 1, characterized in that, the tap-changer and the tap selector are arranged in parallel in the axial direction and arranged in a triangular relationship in the lateral direction, and the upper part is a switch switch, below is the tap selector. 3. The on-load tap-changer mounted outside the transformer according to claim 2, wherein the tap selector includes a single-group tap selector and a double-group tap selector, and the single-group tap selector . The double-group tap selectors are arranged in parallel with the axial direction and are respectively arranged on the left and right sides or the upper and lower sides below the tap changer. 4. The on-load tap-changer mounted outside the transformer according to claim 2, characterized in that the compound sheave mechanism controls the actions of the single group tap selector, the double group tap selector and the diverter switch and their actions phase relationship between them. 5. The on-load tap-changer mounted outside the transformer according to any one of claims 1 to 4, wherein the first vertical plate and the second vertical plate are made of metal materials through casting or welding. 6. The on-load tap-changer mounted outside the transformer according to any one of claims 1 to 4, wherein the first vertical plate and the second vertical plate are molded from insulating materials. 7. The transformer external on-load tap changer according to any one of claims 1 to 4, characterized in that, in the tap changer, the transition function is a vacuum tube contact assembly.

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