JPH0225217Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a tap switching device, particularly a voltageless tap switching device or a load tap switching device using a load tap selection method.

[Prior art]

FIG. 1 shows the conventional configuration of this type of device.

In this figure, W _M is the winding of the transformer, L ₁ is its terminal, and W _T is the tap winding of the transformer, which has multiple taps T ₁ , T ₂ , T ₃ ... _TN . , the voltage is adjusted by selecting an appropriate tap from these and connecting it to the terminal _L1 of the transformer winding. The CM is a switching mechanism for switching the taps mentioned above, and is configured as follows. That is,
C ₁ is a first contact row, in which a plurality of fixed contacts C ₁₁ , C ₁₂ , C ₁₃ ... C _1N are arranged at equal intervals on the circumference, and a plurality of fixed contacts are individually connected to each fixed contact. Lead wires _L2 are connected to the above-mentioned taps _T1 , _T2 , _T3 , . . . _TN , respectively.

Further, C ₂ is a second contact row, which is connected to the first contact row.
Similar to the contact row, a plurality of fixed contacts C ₂₁ , C ₂₂ , C ₂₃ . . . C _2N are arranged at equal intervals on the circumference. Furthermore, the second contact row _C2 is arranged coaxially and parallel to the first contact row _C1 , and the fixed contacts are positioned to face each other. The contacts of the second contact row _C2 are all electrically connected by a lead wire _L3 , and the lead wire _L3 is connected to the terminal _L1 of the transformer winding _WM . .

Further, C ₀ is a movable contact, which has a size and structure that can contact each corresponding contact in the first and second contact rows, and is rotated by an appropriate rotation device (not shown). , moves along the circumference of each contact row, and selectively bridges any one set of corresponding contacts in both contact rows. It is well known that by changing the bridge position, the tap is changed and the voltage is adjusted. In the case of three sets, three sets of the above configuration are prepared, but the contact rows of each phase are arranged coaxially, and the movable contacts of each phase are rotated by a common rotation device. It is something.

The conventional device is configured as described above, but
In addition to ensuring mutual insulation between each contact row, it is also necessary to secure space for installing a shield ring for ground shielding, which increases the size of the tap switching mechanism and complicates the structure. It had the disadvantage of being expensive.

[Summary of the idea]

This invention was made in order to eliminate these drawbacks, and by considering the arrangement of the contact rows, it is possible to attach the ground shield ring without any trouble.

[Example of idea]

An embodiment of this invention shown in FIG. 2 will be described below.

In FIG. 2, 1 is a transformer tank, and 2 is a head mechanism of a tap changer attached to the top plate 1A of the transformer tank, which is maintained at ground potential. 3 is an insulating cylinder attached to the head mechanism 2 and housed in the transformer tank; 4 is a bottom plate of the insulating cylinder; C ₁ A and
C ₂ A is a contact row that constitutes a tap switching mechanism for one phase, and C 1 A is a row of contacts that constitute a tap switching mechanism for one phase, and C ₁ A is a row of contacts that constitute a tap switching mechanism _{for one phase} .
C ₁₂ , C ₁₃ . . . C _1N are mounted on the inner wall of the insulating tube 3 at equal intervals, and correspond to the first contact row C ₁ shown in FIG. Furthermore, C ₂ A _is a structure in which a plurality of fixed contacts C ₂₁ , C ₂₂ , C ₂₃ .
This corresponds to contact row C ₂ . C ₁ B and C ₂ B and
C ₁ C and C ₂ C are the second and third phases, respectively, in the case of three phases.
This figure shows a contact row for each phase, and the individual configurations are the same as those described above. Note that the contact rows C ₁ A and C ₂ A of the phase located closest to the head mechanism 2 at ground potential are the second contact rows.
In FIG. 2, C ₂ A is arranged above the first contact row C ₁ A so that it is closer to the ground than the first contact row C ₁ A. C ₀ A, C ₀ B, and C ₀ C are movable contacts for bridging the corresponding fixed contacts of the first contact row C ₁ and the second contact row C ₂ for each phase, and are well-known roller contacts. will be adopted. 5A, 5B, and 5C are arms that support movable contacts, and 6 is a movable contact C ₀ A of each phase that fixes each of the above arms.
A drive shaft for rotating C ₀ B and C ₀ C. The upper end is connected to the head mechanism 2 to receive the driving force, and the lower end is rotatably attached to the bottom plate 4 of the insulating cylinder 3. Supported.

7 is a ground shield ring, which is immediately above the second contact row C ₂ A, which is located closest to the earth side among the contact rows C 1 A and C ₂ A of _the phase closest to the earth side. It is located in Numeral 8 is a leg portion that supports the ground shield ring, and is supported by each contact in the contact row C ₂ A.

Among the first phase contact rows located closest to the ground side, the second contact row C ₂ A is connected to the leg of the ground shield ring 7 because the plurality of fixed contacts that make up the second contact row C 2 A are all at the same potential. 8 can be supported by each fixed contact without any problem.

Therefore, since the ground shield ring 7 is provided very close to the second contact row C ₂ A, it can be configured very compactly.

Note that if the ground potential is relatively small, the ground shield ring 7 may be omitted and the second contact row
It is also possible to use C ₂ A as an alternative function as a ground shield ring. In this case, if the plurality of fixed contacts are replaced with one annular contact, the ground shielding function will be more complete.

Note that in the above description, an insulating tube is shown as a member that supports the contact row, but this may be a frame made of a combination of a plurality of insulating columns.

Furthermore, although the movable contacts have been described as roller-type, any type of movable contacts that can bridge two contact rows can operate without any problem. Furthermore, although a configuration has been shown in which the second contact rows for all three phases are arranged on the ground side, there is no problem in arranging the second and third phase contact rows counting from the ground side in the opposite manner.

[Effect of idea]

Since this invention is constructed as described above, the ground shield ring can be easily arranged and supported, and the tap switching mechanism as a whole can be constructed compactly.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a conventional configuration, and FIG. 2 is a schematic diagram showing an embodiment of this invention. In the figure, W _M is the transformer winding, W _T is the tap winding, and C ₁
is a first contact row, C ₂ is a second contact row, C ₁₁ and C ₂₁ are fixed contacts, C ₀ is a movable contact, 2 is a tap changer head mechanism, 3 is an insulating cylinder,
7 is a ground shield ring, and 8 is a leg. Note that the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A set of two contact rows in which a plurality of contacts or contacts that can correspond to these contacts are arranged on the circumference, and the number of sets corresponding to the number of phases are coaxially and mutually arranged. They are arranged in parallel, and each contact in one of a set of contact rows is connected to a plurality of taps provided in the transformer tap winding of the corresponding phase, and the contacts in the other contact row are connected to each other. In this device, tap switching is performed by connecting to the main winding of the transformer or the output terminal of the phase of A tap switching device characterized in that the other contact row of the phase contact row disposed closest to the side is located on the ground side, and a ground shield ring is provided at a position close to the ground side. (2) Practical use characterized in that the other contact row of the phase contact rows arranged closest to the ground side is composed of one annular contact, and this annular contact is used as a ground shield ring. A tap switching device according to claim 1 of the patent registration claim.