JPH06101410B2 - Single-phase transformer with load voltage regulator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a single-phase transformer with a voltage regulator during load, and more particularly to a structure for drawing out a bushing in a single-phase transformer with a voltage regulator during load, which is composed of two unit transformers arranged in parallel. The arrangement of the voltage regulator under load.

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. For this reason, 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, the high voltage lead duct 5, the low voltage lead duct 6, the high pressure air bushing 7,
Low pressure air bushing 8 and tertiary air bushing 9A ₁ , 9A
₂ ; 9B ₁ and 9B ₂ were installed above the transformer, so there was a problem in terms of seismic strength. In addition, if these lead ducts and bushings are to be installed at a low position of the transformer in consideration of seismic strength, the installation area will increase.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a split type single-phase transformer excellent in seismic strength without significantly increasing the installation area.

In order to achieve this object, the present invention provides at least one of a high-voltage lead duct and a low-voltage lead duct across the side surfaces of the tanks of each unit transformer that face each other, and from this lead duct, At least one of the low-voltage bushings is pulled out horizontally in parallel with the longitudinal direction of the tank and toward the end side, and the load voltage regulator of each unit transformer is pulled out horizontally at the longitudinal end of the tank. It is characterized by arranging the bushings that are placed so as to be sandwiched from both sides.

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. Unit transformers 1A and 1B that compose a 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) The low-voltage through bushing is drawn out in parallel with the longitudinal direction of the transformer tank and in the horizontal direction, and the load voltage regulator of each unit transformer is connected to the low-pressure through bushing from both sides at the longitudinal end of the transformer tank. 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.

(2) Since the high-voltage through bushing and the low-pressure through bushing are drawn out in parallel with the longitudinal direction of the transformer tank and toward the opposite sides horizontally, the space between the unit transformers is effectively used. 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.

(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) 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.

(9) 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.

In the above-mentioned embodiment, the case of connecting to the gas-insulated busbar by the high-voltage through bushing and the low-pressure through bushing is described, but the present invention is not limited to this, and also in the case of connecting the gas-insulated switchgear to these through-busses. It can be applied similarly.

Further, in the above embodiment, the load voltage regulator of each unit transformer is arranged at both ends of the low voltage through bushing at the longitudinal end of the transformer tank, but it may be arranged at both sides of the high voltage through bushing. In this case, the same effect can be obtained.

Further, in the above-mentioned embodiment, the case where the autotransformer is used as the unit transformer and the case where the transformer is covered with the soundproof wall has been described. It is needless to say that the same can be applied to the case where the three-winding transformer described above is used or the case where the surroundings of the transformer are not covered with a soundproof wall.

As described above, according to the present invention, at least one of the high-voltage lead duct and the low-voltage lead duct is provided across the mutually facing side surfaces of the tank of each unit transformer, and the high-voltage bushing and At least one of the low-voltage bushings is drawn out horizontally in parallel with the longitudinal direction of the tank and toward the end side thereof, and the load voltage regulator of each unit transformer is extended horizontally at the longitudinal end of the tank. Since the drawn bushing is arranged in such a position that it is sandwiched from both sides, the space between each unit transformer and the load voltage regulator can be effectively used to easily pull out the bushing from a low position.
Seismic strength can be improved without significantly increasing the installation area.

[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, 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 voltage lead duct

Claims (1)

[Claims] 1. A tank, an iron core arranged in the tank, a high-voltage winding and a low-voltage winding wound around the iron core,
Plural unit transformers with voltage regulators under load consisting of voltage regulators under load are juxtaposed, and the high voltage winding and low voltage winding of each unit transformer are drawn out from the tank into the high voltage lead duct and low voltage lead duct, respectively. In which the high-voltage connecting lead and the low-voltage connecting lead are connected in parallel to each other, and the high-voltage connecting lead and the low-voltage connecting lead are connected to the high-pressure bushing and the low-pressure bushing, at least one of the high-pressure lead duct and the low-pressure lead duct. Is provided over the side surfaces of the tanks of the unit transformers facing each other, and at least one of the high pressure bushing and the low pressure bushing is directed from this lead duct in parallel with the longitudinal direction of the tank and toward the end side thereof. And pull out horizontally, and further adjust the load voltage of each unit transformer Single-phase transformer with on-load voltage regulator, characterized in that in the longitudinal end and positioned such sandwich the bushings drawn to the horizontal from both sides of the tank.