JPH06101411B2 - Transformer with voltage regulator under load - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load voltage regulator-equipped transformer, and more particularly to a bushing drawing structure in a load voltage regulator-equipped transformer including two unit transformers arranged in parallel.

In view of the recent power 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 unit capacity of the transformer connected to these generators also increases, it is usually divided into three phases for each phase. What constitutes a phase transformer is adopted.

However, in recent years, transportation conditions have become more severe as the location conditions of power plants and substations have deteriorated, and even with the above-mentioned three-phase transformer divided for each phase, the single-phase transformer itself increases due to the increase in power generation capacity. The fact is that the problem has become larger and transportation problems have arisen. Due to this, a so-called split type transformer, in which the single-phase transformer is further divided into a plurality of unit transformers, is adopted to solve the transportation problem.

By the way, in a single-phase transformer with a load voltage regulator consisting of a plurality of such unit transformers, as shown in FIG.
The unit transformers 1A and 1B manufactured with the same specifications, and the load voltage regulators 3A and 3B respectively connected to these unit transformers 1A and 1B via connecting ducts 2A and 2B in the longitudinal direction. Place the unit transformers 1A and 1B side by side with the sides facing each other.
The surroundings are covered with a soundproof wall 4. Also, each unit transformer 1
The high-voltage winding and low-voltage winding (not shown) of A and 1B are connected to the high-voltage connecting lead and the low-voltage lead in the high-voltage lead duct 5 and the low-voltage lead duct 6 arranged above the tank of each unit transformer 1A and 1B. Connected in parallel by connecting leads (not shown), led out to the outside of the soundproof wall 4 via the high pressure air bushing 7 and the low pressure air bushing 8 and further the tertiary winding of each unit transformer 1A, 1B (Fig. (Not shown) is pulled out to the outside of the soundproof wall 4 through a tertiary connection lead (not shown) and tertiary air bushings 9A ₁ , 9A ₂ ; 9B ₁ and 9B ₂ protrudingly provided on the upper surface of the tank. In addition, 10A and 10B are neutral point air bushings projectingly provided on the upper surfaces of the voltage regulators 3A and 3B during load.

Thus, in the conventional split type single-phase transformer with load voltage regulator, not only the high-pressure air bushing 7 and the low-pressure air bushing 8 but also each tertiary air bushing 9A ₁ , 9A ₂ ; 9B ₁ , 9B ₂
Since each unit transformer 1A, 1B is also drawn out, these bushings must be penetrated from the soundproof wall 4,
In addition to the need to take measures against water leakage and sound leakage at the penetrations, the height of the bushing pocket is also high, and seismic measures are also troublesome, which has the drawback of leading to cost up.

An object of the present invention is to provide an inexpensive transformer with a voltage regulator during load, which has a reduced number of bushings for noise barriers except the above-mentioned drawbacks of the prior art.

In order to achieve this object, the present invention connects a bushing (for example, a tertiary air bushing) connected to a winding (for example, a tertiary winding) that excites an exciting winding of a load voltage regulator in a main transformer. It is characterized in that the soundproof habit is pulled out through the duct from the load voltage regulator arranged outside the soundproof wall without penetrating the soundproof habit, and the soundproof wall penetrating portion of the bushing is eliminated.

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

FIG. 2 is a connection diagram of a single-phase transformer according to an embodiment of the present invention. The single-phase transformer consists of two unit transformers 1A and 1B,
Each unit transformer 1A, 1B has a load voltage regulator 3A, 3B respectively
Is included. Each unit transformer 1A, 1B has a series (high voltage) winding 11, a shunt (low voltage) winding 12 and a tertiary winding 13, and each unit transformer 1A, 1B has a series winding 11 and a shunt winding. 12 are connected in parallel by a high voltage connection lead 14 and a low voltage connection lead 15, respectively, and are guided to a high voltage through bushing 16 and a low voltage through bushing 17.

In addition, each load voltage regulator 3A, 3B includes an excitation winding 18 connected in parallel with the tertiary winding 13, a tap winding 19 connected in series with the shunt winding 12, and a tap of the tap winding 19. And the tertiary winding 13 and the excitation winding 18 connected in parallel in each unit transformer have a tap switching device 20 for switching
21A ₁ , 21A ₂ ; 21B ₁ , 21B ₂ respectively, and tap changer 2
0 is led to the neutral point air bushings 22A and 22B, respectively.

The structure of the single-phase transformer thus connected is shown in FIGS. 3 and 4. Each single-phase transformer 1A, 1B that constitutes the single-phase transformer
Are arranged side by side in parallel so that their longitudinal sides face each other, and are covered with a soundproof wall 4. Each of the unit transformers 1A and 1B includes a tank 23, an iron core 24 arranged in the tank 23, the series winding 11 wound around the main leg of the iron core 24, and a shunt winding.
It is composed of a winding 25 consisting of 12 and a tertiary winding 13.

The high-voltage connecting lead 14 and the low-voltage connecting lead 15 of each unit transformer 1A, 1B have a height approximately equal to the height position of the center of gravity of the unit transformer on the mutually facing sides of the tank 23 of each unit transformer 1A, 1B. Of the high-voltage lead duct 26 and the low-voltage lead duct 27, which form a substantially double-sided frame by connecting the two locations, and the high-voltage connecting leads 14 are erected from there to the high-voltage penetrating lead. While being connected to one end of the bushing 16, the other low-voltage connection lead 15 is
From there, it is bent outward in the horizontal direction and is connected to one end of a low-voltage through bushing 17.

The high pressure through bushing 16 and the low pressure through bushing 17 are
Each of the conductors of the high-voltage gas-insulated busbar 28 and the low-pressure gas-insulated busbar 31 extends at the other ends of the unit transformers, which extend parallel to the longitudinal direction of the unit transformer and extend horizontally toward the opposite sides of the unit transformer. The conductor 32 is connected. The high-voltage through bushing 16 arranged in this way has a high-pressure connecting duct 34, one end of which is connected above the high-voltage lead duct 26, and a high-pressure gas-insulated busbar 28, one end of which is connected to the other end of the high-voltage connecting duct 34. The low-pressure through bushing 17 is covered with the sheath 30, and the low-pressure through bushing 17 is similarly connected to the low-pressure connecting duct 35 whose one end is connected to the side of the low-voltage lead duct 27 and one end is connected to the other end of this low-pressure connecting duct 35. Low voltage gas insulated busbar 31 sheath 33
Covered by.

Load voltage regulator 3A, 3B attached to each unit transformer 1A, 1B
Are connected to the end faces of the tanks 23 of the unit transformers 1A and 1B through load-time voltage regulator connection ducts 2A and 2B, respectively, and are arranged so as to sandwich the low-pressure gas insulated busbar 31 from both sides.

Further, the tertiary penetration bushings 21A ₁ , 21A ₂ ; 21B ₁ , 21B ₂ and neutral point air bushings 22A, 22B are respectively drawn from the upper surface of the tank of each load voltage regulator 3A, 3B, and the tertiary penetration bushings The bushings 21A ₁ , 21A ₂ ; 21B ₁ , 21B ₂ project into the respective tertiary gas-insulated buses 36A ₁ , 36A ₂ ; 36B ₁ , 36B ₂ .

Main unit neutral point connecting leads 37A, 37B for connecting the neutral side of the shunt winding 12 in each unit transformer 1A, 1B to the tap winding 19 of the load voltage regulator 3A, 3B, and the tertiary winding The tertiary connection leads 38A ₁ , 38A ₂ ; 38B ₁ , 38B ₂ for connecting the wire 13 to the tertiary feedthrough bushings 21A ₁ , 21A ₂ ; 21B ₁ , 21B ₂ are approximately connected to the load voltage regulator connection ducts 2A, 2B. Neutral point through bushing 39A, 39B and tertiary through bushing 40A ₁ , supported in the middle
40A ₂ ; 40B ₁ and 40B ₂ are introduced into the tanks of the voltage regulators 3A and 3B under load.

According to this embodiment having such a configuration, the following various effects can be obtained.

(1) Since the tertiary penetration bushings 21A ₁ , 21A ₂ ; 21B ₁ and 21B ₂ were pulled out from the load voltage regulator located outside the soundproof wall, the soundproof wall does not have the penetration portion of this tertiary penetration bushing. It is not necessary to take measures against water leakage and sound leakage, the height of the bushing pocket can be lowered, and earthquake-proof measures can be easily performed, so that the transformer can be manufactured at low cost.

(2) Since the high-voltage connection lead and the low-voltage connection lead of each unit transformer are drawn out from the positions of the tanks of each unit transformer that face each other and the positions that face each other, the corresponding lead-out positions of these connection leads Are close to each other, and the lengths of the high-voltage lead duct and the low-pressure lead duct that are provided so as to straddle between the respective drawing positions can be short. as a result,
These lead ducts can be manufactured at low cost, and the work of connecting the high-voltage connecting lead and the low-voltage connecting lead becomes easy.

(3) By connecting high-pressure lead ducts and low-voltage lead ducts at the heights approximately equal to the height of the center of gravity of the unit transformers on the sides of the tanks of the unit transformers that face each other, a substantially cross-shaped framework is formed. Since it is configured, the two unit transformers can be integrated and stably respond to an earthquake, and the seismic strength of the transformer can be greatly improved.

(4) Since the high-voltage through bushing and the low-voltage through bushing are drawn out from the central portions of the high-voltage lead duct and the low-voltage lead duct, the influence on the locking of the transformer foundation in the event of an earthquake is reduced, and the support and fixing part of the through bushing is By the synergistic effect with the low height, the seismic resistance of the through bushing can be greatly improved.

(5) One end of the high-voltage connecting duct is placed above the high-voltage connecting duct, and part of the weight of the high-voltage connecting duct is taken up by the high-pressure connecting duct. The mechanical strength at the connecting portion of these ducts can be significantly improved as compared with the case where they are connected and cantilevered.

(6) Since one end of the high-voltage connecting duct is connected above the high-voltage lead duct, the protruding length of the high-pressure gas-insulated bus bar to the outer side is larger than that of the above-mentioned cantilevered support, because it is mounted above this high-voltage lead duct. Therefore, the installation area can be reduced.

(7) Since the installation positions of the high-voltage lead duct and the low-voltage lead duct are low, the safety of the installation work can be improved.

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

(9) Since the high-voltage through bushing and the low-voltage through bushing are drawn out in parallel with the longitudinal direction of the transformer tank and toward the opposite sides horizontally, the through bushing is effectively utilized by utilizing the space between the unit transformers. Can be easily pulled out from a lower position and connected to the gas-insulated busbar, and although the seismic strength is excellent, the installation area can be kept small.

The winding of the unit transformer does not have a tertiary winding, but consists of a series (high voltage) winding and a shunt (low voltage) winding. The shunt winding excites the excitation winding of the load voltage regulator. In this case, the same effect as in the above embodiment can be obtained by pulling out the low voltage bushing connected to this shunt winding from the load side voltage regulator side.

Further, in the above-mentioned embodiment, the split type single-phase autotransformer was described as the transformer, but the present invention is not limited to this, and it is needless to say that the present invention can be widely applied to other transformers with a voltage regulator during load. is there.

As described above, according to the present invention, the winding for exciting the exciting winding of the load voltage regulator in the main transformer, for example, the bushing connected to the tertiary winding or the low-voltage winding is connected to the connecting duct. Through, without pulling through the soundproof wall from the load voltage regulator located outside the soundproof wall, and eliminating the soundproof wall penetration part of this bushing, it is not necessary to take measures against water leakage and sound leakage in this part, This type of transformer can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a plan view showing a schematic configuration of a conventional split type single-phase transformer with a load voltage regulator, and FIG. 2 is a single-phase transformer with a load voltage regulator according to an embodiment of the present invention. Connection diagram, FIG. 3 is a partially cutaway plan view of the same single-phase transformer, and FIG. 4 is A- of FIG.
It is a partially broken side view in the A line. 1A, 1B …… Unit transformer, 2A, 2B …… Load voltage regulator connection duct, 3A, 3B …… Load voltage regulator, 4 …… Soundproof wall, 1
1 …… Series (high voltage) winding, 12 …… Shunt (low voltage) winding, 13
…… Tertiary winding, 16 …… High voltage through bushing (first bushing), 18 …… Excitation winding, 21A ₁ , 21A ₂ ; 21B ₁ , 21B ₂ ......
Tertiary penetration bushing (second bushing)

Claims (1)

[Claims] 1. A main transformer and a load voltage regulator are connected by a connecting duct, the main transformer is covered with a soundproof wall, and the load voltage regulator is arranged outside the soundproof wall. A winding for exciting the first winding connected to the high-voltage winding of the main transformer from the main transformer side through the soundproof wall to excite the excitation winding of the load voltage regulator in the main transformer. A second load bushing connected to a wire is drawn out through the connection duct from the load voltage regulator arranged outside the soundproof wall without penetrating the soundproof wall. Transformer with regulator.