JPS6249970B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a single-phase transformer with an on-load voltage regulator, and more particularly to a lead-out structure of connection leads and bushings in two unit transformers arranged side by side, and an arrangement of the on-load voltage regulator.

In view of the recent electricity situation, the power generation capacity of power plants has been increasing. Due to this increase in power generation capacity, multiple generators may be installed, but since the single unit capacity of the transformers connected to these generators also increases, they are usually divided into three generators for each phase. What constitutes a phase transformer is adopted.

However, transportation conditions have become increasingly severe in recent years as the location conditions for power plants and substations have deteriorated, and even if the three-phase transformer is divided into each phase as described above, the single-phase transformer itself is becoming smaller due to the increase in power generation capacity. The reality is that they have become larger, creating transportation problems. For this reason, a so-called split-type transformer, in which a single-phase transformer is further divided into a plurality of unit transformers, is used to solve transportation problems.

By the way, in such a single-phase transformer with on-load voltage regulator consisting of a plurality of unit transformers, the first
As shown in the figure, each unit transformer 1A, 1B manufactured with the same specifications, and these unit transformers 1A,
The on-load voltage regulators 3A and 3B, which are separately connected to 1B via connection ducts 2A and 2B, are arranged side by side with their longitudinal sides facing each other, and the surroundings of each unit transformer 1A and 1B are It is covered with a soundproof wall 4. In addition, the high voltage winding and low voltage winding (not shown) of each unit transformer 1A, 1B are connected to each unit transformer 1A, 1B.
A high pressure lead duct 5 and a low pressure lead duct 6 arranged above the tanks A and 1B are connected in parallel by high pressure connection leads and low pressure connection leads (not shown), and high pressure air bushings 7 and low pressure air It is drawn out to the outside of the soundproof wall 4 through the middle bushing 8, and further connected to each unit transformer 1A,
The tertiary winding (not shown) of 1B is connected to the soundproof wall via a tertiary connection lead (not shown) and tertiary air bushings 9A ₁ , 9A ₂ ; 9B ₁ , 9B ₂ protruding from the top of the tank. 4 It is pulled out to the outside. In addition, 10
A, 10B are neutral point air bushings protruding from the upper surface of each on-load voltage regulator 3A, 3B.

As described above, in the conventional split type single-phase transformer with on-load voltage regulator, the high voltage lead duct 5, the low voltage lead duct 6, the high pressure air bushing 7, the low pressure air bushing 8, and the tertiary air bushing 9A ₁ , 9
Since A ₂ ; 9B ₁ and 9B ₂ are installed above the transformer, there is a problem in terms of seismic strength, and these lead ducts and bushings should be placed at a lower position on the transformer in consideration of seismic strength. If you try to install one, the problem arises that the installation area will increase.

An object of the present invention is to solve the problems of the prior art described above and to provide a split-type single-phase transformer with an on-load voltage regulator that has excellent seismic strength without significantly increasing the installation area.

In order to achieve this object, the present invention connects the tank of each unit transformer at a height approximately equal to the height position of the center of gravity of the unit transformer on mutually opposing sides by a high voltage lead duct and a low voltage lead duct. The high-pressure bushings and low-pressure bushings are pulled out horizontally from the high-pressure lead duct and low-pressure lead duct parallel to the longitudinal direction of the tank and toward opposite sides, and each unit is It is characterized in that the load voltage regulator of the transformer is placed in a position sandwiching the low-voltage bushing drawn out horizontally at the longitudinal end of the tank from both sides.

Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

FIG. 2 is a wiring diagram of a single-phase transformer according to an embodiment of the present invention. A single phase transformer consists of two unit transformers 1
Each unit transformer 1A, 1B is attached with a load voltage regulator 3A, 3B, respectively. Each unit transformer 1A, 1B has a series (high voltage) winding 11, a shunt (low voltage) winding 12, and a tertiary winding 1.
3, each unit transformer 1A, 1B has a series winding 1
1 and the shunt winding 12 are connected in parallel by a high-voltage connecting lead 14 and a low-voltage connecting lead 15, respectively, and lead to a high-voltage through bushing 16 and a low-voltage through bushing 17.

Each on-load voltage regulator 3A, 3B also includes an excitation winding 18 connected in parallel to the tertiary winding 13, a tap winding 19 connected in series to the shunt winding 12,
The tertiary winding 13 and the excitation winding 18 connected in parallel of each unit transformer have tertiary through bushings 21A ₁ , 21A ₂ ; 21B ₁ , 21B _{2 .} The tap changer 20 is led to neutral point air bushings 22A and 22B, respectively.

The configuration of a single-phase transformer connected in this manner is shown in FIGS. 3 and 4. The unit transformers 1A and 1B constituting the single-phase transformer are arranged in parallel so that their longitudinal sides face each other, and are covered with a soundproof wall 4. Each unit transformer 1A, 1B has a tank 23,
An iron core 24 disposed within this tank 23, and the series winding 1 wound around the main leg of this iron core 24.
1, a winding 25 consisting of a shunt winding 12 and a tertiary winding 13.

High voltage connection lead 14 of each unit transformer 1A, 1B
and low voltage connection lead 15 for each unit transformer 1
A high-voltage lead duct 26 and a low-voltage lead duct 27 constitute an approximately # digit-shaped framework that connects the mutually opposing sides of the tanks 23 of A and 1B at a height approximately equal to the height position of the center of gravity of the unit transformer. One high voltage connection lead 14 rises upward from there and is connected to one end of the high voltage through bushing 16, while the other low voltage connection lead 15 extends horizontally outward from there. Low pressure through bushing 17 bent in the direction
connected to one end of the

The high-voltage through bushing 16 and the low-voltage through bushing 17 each extend horizontally parallel to the longitudinal direction of the unit transformer and toward opposite sides, and each has a high-pressure gas insulated bus bar at the other end that protrudes outside the soundproof wall 4. 28 conductors 29 and the conductor 32 of the low pressure gas insulated bus bar 31 are connected. The high voltage through bushing 16 arranged in this way has one end connected to the high voltage connection duct 34 above the high voltage lead duct 26, and one end connected to the other end of the high voltage gas insulated bus bar 28. sheath 30
and a low pressure through bushing 17.
Similarly, it is covered by a low-pressure connection duct 35 whose one end is connected to the side of the low-pressure lead duct 27, and a sheath 33 of the low-pressure gas insulated bus bar 31 whose one end is connected to the other end of the low-pressure connection duct 35. It is being said.

On-load voltage regulators 3A and 3B attached to each unit transformer 1A and 1B are respectively connected to the end face of the tank 23 of each unit transformer 1A and 1B via on-load voltage regulator connection ducts 2A and 2B, It is arranged so as to sandwich the low pressure gas insulated bus bar 31 from both sides.

Further, the tertiary through bushings 21A ₁ , 21
A ₂ ; 21B ₁ , 21B ₂ and neutral point air bushings 22A, 22B are connected to each load voltage regulator 3A,
The tertiary through bushings 21A ₁ , 21A ₂ ; 21B ₁ ,
21B ₂ is each tertiary gas insulated busbar 36A ₁ , 36A ₂ ;
They protrude into 36B ₁ and 36B ₂ , respectively.

Shunt winding 12 in each unit transformer 1A, 1B
Main body neutral point connection leads 37A, 37B for connecting the neutral point side of the tertiary winding 13 to the tap winding 19 of the load voltage regulators 3A, 3B, and tertiary through bushings 21A ₁ , 21A ₂ ; ₁ , 21B ₂ tertiary connection leads 38A ₁ , 38A ₂ ;
38B ₁ , 38B ₂ are connected through body neutral point through bushings 39A, 39B and tertiary through bushings 40A ₁ , _{40A 2 ;} It is led into the tanks of the on-load voltage regulators 3A and 3B.

According to this embodiment configured in this manner, the following various effects can be obtained.

(1) Since the high-voltage connection lead and low-voltage connection lead of each unit transformer were pulled out from mutually opposing sides of the tank of each unit transformer and from mutually opposing positions, each of the corresponding pull-out positions of these connection leads Therefore, the lengths of the high-pressure lead duct and the low-pressure lead duct that are provided across these extraction positions can be shortened. As a result, these lead ducts can be manufactured at low cost, and the work of connecting the high-voltage connection lead and the low-voltage connection lead becomes easy.

(2) A nearly # girder-shaped framework is constructed by connecting the opposite sides of the tank of each unit transformer at a height approximately equal to the height position of the center of gravity of the unit transformer using high-voltage lead ducts and low-voltage lead ducts. As a result, the two unit transformers work together to stably respond to earthquakes.
The seismic strength of the transformer can be significantly improved.

(3) Since the high-voltage through-butting and the low-voltage through-butting are drawn out from the center of the high-voltage lead duct and the low-voltage lead duct, the impact on the rocking of the transformer foundation in the event of an earthquake is reduced, and the support and fixation of the through-butting is reduced. Due to the synergistic effect with the low height of the through bushing, the seismic strength of the through bushing can be greatly improved.

(4) One end of the high-voltage connection duct is placed above the high-pressure lead duct, and part of the weight of the high-voltage connection duct is borne by the high-pressure lead duct, so one end of the high-voltage connection duct is placed on the side of the high-pressure lead duct. Compared to the case where the ducts are connected and supported in a cantilevered manner, the mechanical strength of the connecting portions of these ducts can be significantly improved.

(5) Since one end of the high-voltage connection duct is connected above the high-pressure lead duct, the outward protrusion of the high-pressure gas insulated bus bar is increased by the amount placed above the high-pressure lead duct, compared to the above case of cantilever support. The length can be shortened and the installation area can be reduced.

(6) Since the high-pressure lead duct and low-pressure lead duct are installed at low positions, the safety of the installation work can be improved.

(7) Tertiary through bushing 21A ₁ , 21A ₂ ; 21
Since B ₁ and 21B ₂ are drawn out from the load voltage regulator located outside the soundproof wall, there is no penetration part of this tertiary through bushing in the soundproof wall, and there is no need to take measures against water leakage and sound leakage in this part.
The height of the bushing pocket can be reduced, earthquake resistance measures can be easily implemented, and the transformer can be manufactured at low cost.

(8) Pull out the low-voltage through bushing horizontally and parallel to the longitudinal direction of the transformer tank, and pull out the on-load voltage regulator of each unit transformer from both sides of the low-voltage through bushing at the longitudinal end of the transformer tank. Because it is placed in a sandwiching position, the space between each unit transformer and on-load voltage regulator can be effectively used to easily pull out the low-voltage bushing from a low position, and it has excellent earthquake resistance. Regardless, the increase in installation area is small.

(9) Since the high-voltage through-butting and the low-voltage through-butting are pulled out horizontally parallel to the longitudinal direction of the transformer tank and toward opposite sides, the space between each unit transformer can be effectively utilized to can be easily pulled out from a low position and connected to a gas-insulated busbar, and despite its excellent seismic strength, the installation area does not need to be increased much.

In the above embodiment, a case was described in which the high voltage through bushing and the low voltage through bushing are connected to the gas insulated bus bar, but the present invention is not limited to this, and the present invention is not limited to this. It can be similarly applied to cases where air bushings are used instead of bushings to connect to overhead lines.

Further, in the above embodiment, the case where an auto-transformer is used as the unit transformer is described, but it can be similarly applied to the case where a three-winding transformer consisting of separate high-voltage, low-voltage, and tertiary windings is used. Of course.

As explained above, according to the present invention, the high-voltage bushing and the low-voltage bushing are drawn out horizontally from the high-voltage lead duct and the low-voltage lead duct in parallel to the longitudinal direction of the tank and toward opposite sides, and further, each unit transformer is The on-load voltage regulator is placed at the longitudinal end of the tank so as to sandwich the horizontally drawn out low-voltage bushing from both sides, making the space between each unit transformer and the on-load voltage regulator effective. The bushing can be easily pulled out from a low position by using the bushing, and seismic strength can be improved without significantly increasing the installation area. In addition, a high-voltage lead duct and a low-voltage lead duct connect the opposite sides of the tank of each unit transformer at a height approximately equal to the height position of the center of gravity of the unit transformer to form a framework approximately in the shape of a # girder. With this structure, the two unit transformers work as one to stably respond to earthquakes, and from this point of view as well, seismic strength can be greatly improved.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing a schematic configuration of a conventional split single-phase transformer, Fig. 2 is a wiring diagram of a single-phase transformer according to an embodiment of the present invention, and Fig. 3 is a diagram of the same single-phase transformer. A partially cutaway plan view, and FIG. 4 is a partially cutaway side view taken along line AA in FIG. 3. 1A, 1B...Unit transformer, 3A, 3B...Load voltage regulator, 14...High voltage connection lead, 15
...Low voltage connection lead, 16...High voltage through bushing, 17...Low voltage through bushing, 23...Transformer tank, 26...High voltage lead duct, 27...
Low pressure lead duct.

Claims (1)

[Claims] 1. A unit transformer with an on-load voltage regulator consisting of an independent tank, an iron core placed in this tank, high-voltage windings and low-voltage windings wound around this iron core, and an on-load voltage regulator. High-voltage connection leads are placed in parallel and lead out the high-voltage winding and low-voltage winding of each unit transformer from the tank of each unit transformer into high-voltage lead ducts and low-voltage lead ducts, respectively, which are configured separately from these tanks. and are connected in parallel to each other by low voltage connecting leads, and the high voltage connecting lead and the low voltage connecting lead are connected to a high voltage bushing and a low voltage bushing provided in the high voltage lead duct and the low voltage lead duct, wherein each of the unit transformers The high-voltage lead duct and the low-voltage lead duct connect the opposite sides of the tank at a height approximately equal to the height position of the center of gravity of the unit transformer to form an approximately # girder-shaped framework. The high-voltage bushing and low-voltage bushing are pulled out horizontally from the high-voltage lead duct and the low-voltage lead duct parallel to the longitudinal direction of the tank and facing oppositely to each other, and the on-load voltage regulator of each of the unit transformers is pulled out from the tank. 1. A single-phase transformer with an on-load voltage regulator, characterized in that the horizontally drawn out low-voltage bushing is placed at a longitudinal end portion of the transformer so as to sandwich the low-voltage bushing from both sides.