WO2011022906A1

WO2011022906A1 - Cage-style tap-changer without excitation for transformer

Info

Publication number: WO2011022906A1
Application number: PCT/CN2009/075692
Authority: WO
Inventors: 秦伟
Original assignee: 武汉泰普变压器开关有限公司
Priority date: 2009-08-26
Filing date: 2009-12-18
Publication date: 2011-03-03
Also published as: CN101661833A; CN101661833B; DE112009005164B4; DE112009005164T5

Abstract

A cage-style tap-changer without excitation for transformer includes up and down brackets (2, 3) and insulating poles (4) connected between them along peripheral direction. There are interval annular fixed contacts (7) on the axes of the insulating poles (4). There is a moving contact assembly (6) between the up and down brackets (2, 3) and on the inner of the annular fixed contacts (7). The moving contact assembly (6) is connected to an up-and-down gearing. Moving contacts are mounted on the circumference of the moving contact assembly (6) and correspond to the annular fixed contacts (7) and are connected with two adjacent fixed contacts. The annular fixed contacts (7) are staggered and connected at intervals with the insulating poles (4) that are mounted along peripheral direction. The up and down two adjacent annular fixed contacts (7) are not connected with the same insulating pole (4). Reserve oil clearances (8) are formed between the annular fixed contacts (7) and another insulating pole (4) with which is disconnected.

Description

Non-excited cage-shaped tap changer for transformers

The invention relates to a non-excitation tap changer for a transformer, which is a further improvement of the existing non-excited cage tap changer.

Background technique

In the Chinese utility model patent specification with the authorization bulletin number CN200944364Y, a non-exciting cage-shaped tap changer is disclosed, which is provided with an annular static contact, the annular static contact is distributed along the axial direction, and is fixed in the circumferential direction by the outer circle. Such annular static contacts on the various insulating rods arranged can enhance the mechanical strength and rigidity of the cage insulator. The switch moving contact slides up and down in the ring of the ring-shaped static contact to bridge two adjacent static contacts to realize the voltage regulating function. The contact point of the switch contacts can achieve a large current and has good rigidity. In view of the above characteristics, the switch is often used in high voltage applications, and the higher the adjacent static contact voltage, the greater the creepage margin between adjacent stationary contacts according to the insulation properties of the insulating rod material arranged in the circumferential direction. Therefore, when the voltage between the contacts is high and the gear position is high, the switch height will be high, which not only makes the overall rigidity of the switch worse, but also takes up too much space and is not convenient for installation on the transformer. At present, the capacity of a single transformer is getting larger and larger, and the voltage level is getting higher and higher. The above defects are also more prominent.

Summary of the invention

The technical problem to be solved by the present invention is to provide a non-excited cage-type tap changer with good rigidity, small height and high insulation performance by avoiding the deficiencies of the prior art described above.

The technical solution adopted by the present invention to solve the above-mentioned problems is as follows: the upper and lower supports 2, 3 are provided, and the insulating rods 4 are circumferentially coupled between the upper and lower supports, and the annular spacing is arranged along the axial direction of the insulating rods. The static contact 7 is provided with a movable contact assembly between the upper and lower supports and the inner side of the annular static contact, the movable contact assembly is coupled with the upper and lower transmissions, and the outer circumference of the movable contact assembly 6 is corresponding to the annular static contact. There is a movable contact which is connected with two adjacent static contacts, and the difference is that the annular static contact is alternately connected with the circumferentially disposed insulating rod, and the upper and lower adjacent annular fixed contacts 7 are not insulated from the same The rods 4 are coupled and leave a gap 8 between the annular stationary contact and the non-coupled insulating rod.

According to the above scheme, the annular static contact and the circumferentially disposed insulating rod are alternately connected by 1 to 3, that is, the annular static contact is separated by 1 to 3 annular static contacts and then connected with the same insulating rod. .

According to the above scheme, the insulating support ring 9 can be connected between the insulating rods arranged in the circumferential direction, and the insulating support ring is disposed between the two static contacts, the outer circle is connected with the insulating rod, and the inner circle diameter is larger than the annular static contact The diameter of the inner diameter of the head.

According to the above scheme, the circumferentially spaced insulation rods are arranged 1 to 3 turns in the radial direction; for the 2 to 3 turns of insulation The inner ring insulating rod of the rod and the outer ring insulating rod are alternately arranged in the circumferential direction.

According to the above solution, the annular fixed contact outer circle is provided with a coupling boss, which is connected to the insulating rod through the coupling boss. The invention has the following advantages: 1. The main feature of the invention is that the adjacent static contacts are not fixed on the same insulating rod, and some even are separated by two static contacts, because the annular static contacts are not connected with each other. A sufficient oil gap is left between the insulating rods, so that the insulation creepage distance on the insulating rod is multiplied in the same axial spacing of the ring-shaped static contacts, which will improve the internal insulation level of the switch or be effective. Reduce the axial height of the switch, that is, the level of insulation between the stages is increased at the same height of the switch, or the total height of the switch is reduced at the same height; 2. The stiffness of the cage insulator composed of the insulating rods can be increased by adding an insulating support ring. It can be enhanced and improved. 3. Set 2 turns of insulation rod to further improve the inter-stage insulation level of the gate, improve the inter-stage insulation, facilitate the layout of the terminal on the ring-shaped static contact or further improve the inter-stage insulation through the oil-gathering gap; The invention also has the characteristics of compact structure and reasonable arrangement.

DRAWINGS

Figure 1 is a front elevational view of one embodiment of the present invention.

Figure 2 is a cross-sectional view taken along line E-E of Figure 1.

Figure 3 is a cross-sectional view taken along line F-F of Figure 2;

Figure 4 is a front elevational view of another embodiment of the present invention.

Figure 5 is a cross-sectional view taken along line G-G of Figure 4;

Figure 6 is a cross-sectional view taken along line H-H of Figure 4;

detailed description

Embodiments of the present invention will be further described below with reference to the accompanying drawings.

The embodiment of the present invention, as shown in Figures 1, 2, and 3, is a single-phase non-excited cage-shaped tap changer having upper and lower supports 2, 3, and a drive screw 5 is disposed between the upper and lower supports. The upper part of the driving screw is connected with the operating mechanism 1, and the driving screw is arranged with a screw sleeve connected with the movable contact assembly 6, and constitutes a screw type upper and lower transmission device; the upper and lower transmission device can also adopt a telescopic cylinder or a rack and pinion device. 6 insulating rods 4 are arranged in the circumferential direction between the upper and lower supports, annular fixed contacts 7 are arranged along the axial direction of the insulating rods, and the connecting rods 12 of the annular static contacts are arranged by the outer circle by bolts 13 and the insulating rods 4 Associative, the annular static contact and the circumferentially mounted insulating rod are alternately connected one after another, that is, one annular static contact is connected with three staggered spaced insulating rods, and the upper and lower adjacent two annular fixed contacts are not the same The insulating rods are coupled, and a gap is left between the annular static contact and the non-coupled insulating rod to form an oil gap 8. The outer circumference of the movable contact assembly 6 is provided with a movable contact that is connected to the adjacent two fixed contacts corresponding to the annular fixed contact. If the number of stages is large, that is, when the number of static contacts is large, a set of insulating rods may be added, so that the annular static contacts are alternately connected with the circumferentially disposed insulating rods, that is, the annular static contacts are separated by two. The annular static contact is further connected with the same insulating rod, so that the adjacent three-layer static contact is fixed on different sets of insulating rods, In this way, the insulation creepage between adjacent stages will be larger and the insulation level will be higher. In order to improve the rigidity of the cage insulator formed by the insulating rod, after the integrated insulation creepage distance, an insulating support ring 9 may be coupled to an appropriate portion between the circumferentially disposed insulating rods, and the insulating support ring is disposed at a distance between the two stationary contacts. Between the outer circle and the insulating rod, the inner diameter is larger than the inner diameter of the annular static contact, and the insulating support ring can also be disposed on the outer circumference of the insulating rod, and the inner diameter of the insulating support ring is connected with the insulating rod. In addition, the terminal 10 is secured to the annular stationary contact by bolts 1 1 as required for connection to the transformer coil.

Another embodiment of the present invention is shown in Figs. 4, 5, and 6, which differs from the previous embodiment in that the circumferentially disposed insulating rod is divided into inner and outer two turns so that the insulating rods are staggered on the circumference of different radii. That is, the insulating rods 4 connected by the adjacent annular static contacts 7 are distributed on different circumferential radii, so that the oil gap 8 can be further enlarged, the interstage insulation is improved, and the oil distance and the creep distance between the static contacts of the switch are further increased. Lifting, thereby improving the insulation performance, also contributes to a reduction in the switch height.

The present invention is equally applicable to a multi-phase switch, such that a multi-phase moving and static contact set is provided on the basis of the above embodiment. At the same time, it can be applied to various wiring principles such as Y-Δ conversion, series-parallel conversion, single-bridge jumper, linear adjustment and so on.

The invention is particularly suitable for high voltage, high current switching, and can meet the needs of large and special type transformers.

Claims

Claim

1. A non-excited cage-shaped tap changer for a transformer, comprising an upper and a lower support, an insulating rod is circumferentially coupled between the upper and lower supports, and an annular static contact is arranged along the axial direction of the insulating rod, a movable contact assembly is disposed between the lower support and the inner side of the annular static contact, and the movable contact assembly is coupled with the upper and lower transmissions, and the outer circumference of the movable contact assembly is provided with the adjacent two static contacts corresponding to the annular static contact The movable contact of the phase jumper is characterized in that: the annular static contact is alternately connected with the circumferentially disposed insulating rod, and the upper and lower adjacent annular fixed contacts are not connected with the same insulating rod, and the annular static contact is An oil gap is left between the insulating rods that are not connected.

2. The non-excited cage-type tap changer for a transformer according to claim 1, wherein: the annular static contact is alternately connected with the circumferentially disposed insulating rods by 1 to 3.

3. The non-excited cage-type tap changer for a transformer according to claim 1 or 2, wherein: an insulating support ring is connected between the insulating rods arranged in the circumferential direction, and the insulating support ring is disposed at a distance between the two stationary contacts. Between the outer circle and the insulating rod, the inner diameter is larger than the inner diameter of the annular static contact.

The non-excited cage-type tap changer for a transformer according to claim 1 or 2, wherein the circumferentially spaced insulating rods are arranged 1 to 3 turns in the radial direction.

5. The non-excited cage-type tap changer for a transformer according to claim 4, wherein: 2 to 3 turns of the insulating rod are disposed, and the inner ring insulating rod and the outer ring insulating rod are alternately arranged in the circumferential direction, which are staggered. The insulating rods are distributed over the circumference of different radii.

The non-excited cage-type tap changer for a transformer according to claim 1 or 2, wherein: the outer ring of the annular static contact is provided with a coupling boss, and is coupled to the insulating rod through the coupling boss.

The non-excited cage-type tap changer for a transformer according to claim 1 or 2, characterized in that: a transmission screw is arranged between the upper and lower supports, and an upper part of the transmission screw is connected with the operating mechanism, and the transmission screw is The screw sleeve phase arrangement associated with the moving contact assembly constitutes a screw type upper and lower transmission device.

The non-excited cage-type tap changer for a transformer according to claim 2, wherein: the annular static contact is alternately connected with the circumferentially disposed insulating rods, and the annular static contacts are separated by two. The annular static contact is then coupled to the same insulating rod to fix the adjacent three static contacts on different sets of insulating rods.

The non-excited cage-type tap changer for a transformer according to claim 1 or 2, wherein the terminal is fixed to the annular static contact by a bolt.