JPH0652121U - Transformer with tap switching device under load - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a special three-phase structural transformer with a tap changer during load, which is easy to transport and assemble, has high reliability, and is inexpensive. [Structure] Single-phase transformers 11 to 13 are provided with single-phase tap selectors 17, and medium-phase transformers 1 to 13 are provided.
2 is provided with a three-phase integrated switching switch 16.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a transformer for a load tap changer, and more particularly to a three-phase transformer capable of split transmission.

[0002]

[Prior art]

 With the development of high-voltage and large-capacity power transformers, the transportation and installation area of large transformers has become a problem. In the case of a three-phase transformer as one of the solutions to the transportation problem, it is composed of three single-phase transformers, the three single-phase transformers are transported separately, and the three-phase transformers are connected at the installation site. The special three-phase structural transformer is adopted. In this case, the following method is adopted for the transformer with load tap changer from the viewpoint of transportation and on-site assembly.

(1) A three-phase load tap switching device for a load is used separately from the transformer, and is connected to the transformer winding by a tap lead wire passing through an oil subduct.

(2) Three single-phase tap changers for load are prepared and installed in separate phase transformers for interlocking.

FIG. 2 is a schematic front view showing a configuration example when a three-phase load tap changer provided separately from the transformer is used. 1 is a single-phase transformer tank, 2 is a transformer Winding wire, 3 is a lead wire duct, 4 is a tap lead wire, 5 is a tap switching device tank, 6 is a switching switch, 7 is a tap selector, 8 is an electric operating mechanism, 9 is a drive shaft, The tanks and ducts are filled with oil.

The tap lead wire 4 drawn from the transformer winding 2 of each phase is connected to a tap selector 7 of a separate three-phase load tap changer for load through a lead wire duct 3 for electric operation. The tap switching operation is performed by the mechanism 8 interlocking the tap selecting operation by the tap selector 7 via the drive shaft 9 and the tap opening / closing operation by the switching switch 6.

[0007]

[Problems to be solved by the device]

 (1) When using the separate three-phase load tap switching device illustrated in FIG. 2 a. Not only the tap switching tank 5 but also the lead wire duct 3 will be transported separately, increasing the transportation cost. Also, the assembly work period at the installation site will be longer than in the case of integrated transportation.

B. The “3 phase x number of taps” tap lead wire 4 must be connected at the installation site. Since 17 or more taps are often specified, the number of tap lead wires is 51 or more. Prolonging the time for opening the contents by connecting these leads to a decrease in reliability.

C. Installation floor area and height increase.

(2) When a single-phase load tap switching device is provided in each phase transformer for interlocking a. The price will increase significantly because three single-phase load tap switching devices with switching switches and tap selectors are required.

B. The external dimensions, weight, and oil amount of each phase transformer increase.

The present invention has been made in view of the above points, and an object thereof is to provide a special three-phase structural transformer with a load tap switching device that is easy to transport and assemble, has high reliability, and is inexpensive. There is.

[0013]

[Means for Solving the Problems]

 Means for solving the above problem in the present invention is to provide a single-phase tap selector for selecting a tap to be switched in each phase transformer, and to select a tap selected in conjunction with the tap selector. A three-phase integrated switching switch for switching to the middle phase transformer is installed.

[0014]

[Action]

 Each single-phase transformer in which the tap switching device under load is stored separately can be transported as a single unit, and the tap switching operation is performed by changing the tap selected in each phase transformer to the three-phase transformer of the middle phase. It is performed by opening and closing with an integrated switching switch.

[0015]

【Example】

 The present invention will be described below based on an embodiment shown in the drawings.

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention. (A) is a front view and (B) is a plan view. In these figures, 11 to 13 are single-phase configuration transformers. A transformer tank, 14 is a transformer winding, 15 is a tap lead wire, 16 is a three-phase integrated switching switch, and is provided in one phase of the transformer tank having a single-phase configuration, for example, in the transformer tank 12. . Reference numeral 17 is a single-phase tap selector provided in each phase transformer, 18 is two lead wires connecting the switching switch 16 and the tap selector 17, 19 is an electric operating mechanism, and 20 is a drive shaft. , 21 are ducts penetrating the lead wire 18 and the drive shaft 20, and the tanks and ducts are filled with disconnection oil. In the case of on-site assembly, the transformer tank 12 equipped with the three-phase integrated switching switch 16 is arranged in the middle, and the transformer tanks 11 and 13 equipped with the tap selectors 17 are arranged on both sides of the transformer tank 12.

The connection in the transformer tanks 11 to 13 of each phase connects the tap lead wire 15 drawn from the transformer winding 14 to the single-phase tap selector 17 provided in the same tank. The odd-sided taps and the even-sided taps selected by each single-phase tap selector 17 are arranged in the center phase of the three phases via the lead wire 18, that is, in the middle-phase transformer tank 12. It is connected to the provided three-phase integrated switching switch 16.

Therefore, while the electric operation mechanism 19 performs the tap selecting operation by the single-phase tap selector 17 provided in the transformer tanks 11 to 13 of each phase via the drive shaft 20, the middle-phase tap selecting operation is performed. The tap switching operation is performed by interlocking the opening and closing operations of the tap by the three-phase integrated switching switch 16 provided in the transformer tank 12.

[0019]

[Effect of device]

 In the transformer with load tap changer according to the present invention, each of the three phases has a single-phase transformer configuration, the single-phase tap selector is housed in each phase transformer, and the middle-phase transformer has three transformers. Because it houses a phase-integrated switching switch, it differs from a separate 3-phase tap switching device for load installation in that it is smaller in size as a whole, and it is low in cost and requires a small installation area. Compared to the dual-load tap switching device and a large-scale duct that stores a large number of tap lead wires, the transport is easier and the transportation cost is reduced, and the assembly work period at the installation site can be shortened.

Further, since the tap selector is housed in the same tank as the transformer winding, not only the tap lead wire is shortened, but also the work related to the contents of the transformer at the installation site such as the connection of the tap lead wire is significantly reduced. It has various practical effects such as shortening, and improvement of reliability by shortening the opening time of the contents.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram for explaining an embodiment of the present invention (A) is a front view and (B) is a plan view

FIG. 2 is a schematic front view showing a conventional configuration example.

[Explanation of symbols]

 11-13 ... Single-phase transformer tank 16 ... Three-phase integrated switching switch 17 ... Single-phase tap selector

Claims (2)

[Scope of utility model registration request] 1. A three-phase transformer is configured by a single-phase transformer for each phase, and a single-phase tap selector is provided in the transformer tank of each of the single-phase transformers, and one phase among them is provided. A transformer with a tap switching device under load, characterized in that a three-phase integrated switching switch is installed in the transformer tank. 2. A transformer tank provided with a three-phase integrated switching switch is arranged in the middle, and a transformer tank provided with only a single-phase tap selector is arranged on both sides of the transformer tank, and each single-phase tap selector is provided. The transformer with a load tap switching device according to claim 1, further comprising a three-phase integrated switching switch.