KR101483066B1 - Zero Load Tap For 30 kv Superconducting Transformer - Google Patents

Abstract

The present invention relates to a no-load tap switcher including: a fixed insulation tap plate which is formed in a longitudinal direction and on which multiple combination grooves are formed; multiple fixed contact points which are formed on the combination grooves of the fixed insulation tap plate; a pair of moving contact points which is in contact with the two fixed contact points, respectively; a gear box which equips a moving rack gear and a pinion gear which move the moving contact point; a driving shaft which supports around the center of the gear box; and a driving handle which moves the driving shaft. The present invention consists of a plurality of input lines and a plurality of output transformations and increases efficiency without the generation of resistance due to transformation without error and easy movement of an electric contact point of a tap. Each deviation reduces since multiple taps use the same shaft. Also, the structure of vibration absorption, waterproof, and airtight is adopted to a driving device and quality and stability are secured.

Description

{30 kV Superconducting Transformer}

The present invention relates to a 30 kV unloaded tapped air supply for distribution, in which three or more electrical connection points of a tap are possible at the same time, and a movable contact is connected to a fixed contact in pairs to maintain stability, This is about ventilating the 30kv no-load taps.

A transformer is a device used to increase or decrease the AC voltage using the mutual induction principle. The transformer utilizes the principle of electromagnet induction to raise or lower a particular voltage level to a higher or lower voltage level.

As is known, electromagnetism induces a voltage on a conductor placed in a variable magnetic field. In a transformer, the variable magnetic field is generated by applying an alternating current to the transformer coil, which is generally indicated as the main coil or winding.

This main winding is typically coupled to a secondary winding or coil, and a main winding and a secondary winding, each comprising a plurality of turns, are wound around the magnetic core. When an alternating current is applied to the main winding, a variable magnetic flux is induced in the core and a voltage is generated in the secondary winding.

In addition to the always inevitable losses, the voltage ratio across the main winding and the secondary winding is ideally equal to the ratio between the number of turns in the main winding and the number of turns in the secondary winding. Therefore, by varying the ratio between the number of turns of the main winding and the number of turns of the secondary windings, the voltage ratio can be varied. In this way it is possible, for example, to control or regulate the voltage across the secondary winding representing the output voltage supplied by the transformer for any load connected to the transformer.

To this end, the transformers have a specific connection, referred to as a tap in the transformer industry. The transformer tap is an electrical connection point that is positioned along either the main winding and / or the secondary windings and allows the number of turns to be selected. The selection of the used tab is made through a tap changer mechanism. For example,

The change mechanism selects the turn at the secondary winding coil to be connected to the load circuit, thereby adjusting the output voltage by varying the ratio of turns at the transformer.

Presently, a certain number of single connection tabs are provided for each coil, for example, each attached to a corresponding turn in the coil and then exposed to the face of the coil, respectively. Typically, each tab is comprised of a lug or flat bar and is, in most cases, welded to the inside of the coil. The taps are then connected by a cable, typically on the face of each coil.

In the transformer, it is preferable that the transformer maintains the voltage of the secondary side (low-voltage side or the load side) at a prescribed rated voltage, but the actual transformer does not have a constant receiving voltage (primary voltage) Since the internal voltage drop of the transformer itself varies continuously depending on the magnitude of the current and the power factor, the output voltage of the secondary side also fluctuates. It is a tap that is provided so that the secondary voltage fluctuating as described above can be adjusted to be close to the rated voltage. The tap is mainly installed in the primary winding of the transformer because it is possible to prevent the iron core from being supersaturated even when the receiving voltage (primary voltage) of the transformer becomes an overvoltage exceeding the rated voltage, and the current flowing in the primary It is possible to reduce the sectional area of the tabs and the tab lead-out leads, which is economical.

The relationship between the transformer voltage and the number of windings is expressed by V1 and N1, where V1 and N2 are the voltage and the number of windings of the primary winding, respectively (V1 / N1 ) = (V2 / N2), the voltage per turn (volts / turn) of the primary and secondary windings is always constant. Here, it can be seen that the secondary voltage V2 is changed in inverse proportion to the number of turns N1 of the primary winding (where V1 and N2 are constant) This is the principle of the difference voltage adjustment.

The transformer taps have a higher number of windings (number of turns) in proportion to the higher voltage taps and a smaller number of turns in the lower voltage taps.

Therefore, when the secondary voltage V2 becomes higher than the rated voltage, when the tap of the primary winding is switched to the higher voltage tap, the number of turns N1 of the primary winding increases, so that the voltage per turn decreases. The difference voltage V2 also decreases.

On the contrary, when the secondary voltage V2 is lower than the rated voltage, the number of turns N1 of the primary winding decreases when the tap of the primary winding is switched to the low voltage tap, so that the voltage per one turn increases and the secondary voltage V2 ) Is increased.

There are two types of tap ventilation: NLTC (No Load Tap Changer) and OLTC (On Load Tap Changer). The NLTC (installed in the high-voltage transformer) is a device that can switch the tap only when the transformer is non-voltage. It is usually used to obtain the desired secondary voltage by switching the tap according to the receiving voltage when installing the transformer. The OLTC is a device that can switch taps during operation of a transformer installed in an ultra-high voltage power transformer. The transformer in operation is a transformer that has voltage drop (ie, primary voltage change) in the transmission / The secondary voltage fluctuates. However, by installing the OLTC, such a secondary voltage fluctuation can be minimized.

Although the above-mentioned transformer has a US prior art which consists only of a multi-connection from a gear box to an electrical connection point of a tap, since a method in which a plurality of outputs are transformed from an external input line is used, There has been a problem.

In addition, the US technology has some drawbacks with respect to the time required in the coil winding manufacturing process, the content of the material used, and the size of the transformer enclosure depth, in particular the use of this single connection tab. Therefore, there is a need to provide a solution that allows for optimization of the manufacturing time in the coil winding process, minimizing the space required inside the transformer enclosure and reducing the material cost associated with the transformer.

In addition, there is a problem that US technology has a simple gear structure and low accuracy.

Also, the shape of the electrical connection points of the tabs can not be easily moved, resulting in a problem of high resistance.

Further, the airtightness is not maintained in the structure for keeping the airtightness in the driving device, and the operation and safety have become a problem.

US Patent Publication No. 03824355

SUMMARY OF THE INVENTION The present invention has been conceived in order to solve the above problems, and it is an object of the present invention to provide a method and apparatus for multi-connection from a gear box 400 to an electrical connection point of a tap, In which a plurality of output transformations are possible at the input line of the input / output terminal, thereby ensuring accuracy.

It is also an object of the present invention to provide a distribution 30 kV no-load tap changer that provides a solution that optimizes the manufacturing time in the coil winding process, minimizes the space required inside the transformer enclosure, and reduces the material cost associated with the transformer.

The present invention also provides a 30 kV no-load tap-changer for power distribution in which the transformer has an accurate transforming capability and does not generate much resistance.

Further, it is an object of the present invention to provide a discharge 30 kV no-load tap changer in which airtightness is maintained in a structure for keeping the airtightness in the drive device.

In order to achieve the above object, the present invention provides an unattached tap changer comprising: a fixed insulated tab which is elongated in the longitudinal direction and has a plurality of engaging grooves; A gear box having a plurality of stationary contacts, a pair of movable contacts for contacting the stationary contacts at the same time, a movable rack gear for moving the movable contacts, and a pinion gear, And a drive handle for moving the drive shaft.

A plurality of the fixed contacts are formed at regular intervals, and various types of the fixed contacts can be transformed at the same time.

The gear box is characterized by comprising a rack gear which moves in the longitudinal direction and a pinion gear which is connected to the rack gear.

The drive handle and the drive shaft may be O-ringed to maintain airtightness.

As described above, since the input line and the output transformer are composed of a plurality of input transformers, error-free transforming is possible and the electrical connection points of the tabs are easily moved, so that resistance is not generated and efficiency is increased.

Further, since a plurality of taps use the same axis, the respective deviations are reduced.

Further, the driving device is provided with dustproof, waterproof, and airtight structure, which ensures the quality and stability.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view showing a 30kv no-load tap changer for distribution according to the present invention; Fig.
2 is a side view showing a 30kv no-load tap changer for distribution according to the present invention;
3 is an enlarged view showing a drive shaft according to the present invention;

Hereinafter, a 30kv no-load tap shifter for power distribution will be described with reference to the accompanying drawings.

FIG. 1 is a plan view showing a 30kv no-load tap changer for a delivery according to the present invention, FIG. 2 is a side view showing a 30kv no-load tap changer for a delivery according to the present invention, .

1 through 3, the present invention provides an unattached tap changer comprising a fixed insulated tab plate 100 formed to be long in the longitudinal direction and having a plurality of engaging grooves, a fixed insulated tab plate 100, A plurality of fixed contacts 200 formed in the coupling groove of the movable contact 300 and a pair of movable contacts 300 contacting the fixed contacts 200 at the same time, A drive shaft 450 for supporting the center of the gear box 400 and a drive handle 500 for moving the drive shaft 450. The gear box 400 includes a gear box 410 and a pinion gear 420, do.

Hereinafter, each configuration will be described in detail.

 The entire structure of the tab tap changer according to the present invention includes a fixed insulating tab plate 100, a stationary contact point 200, a movable contact point 300, a gear box 400, a drive shaft 450 and a drive handle 500. do.

The fixed insulating tap plate 100 uses an insulating material according to a high voltage and is long in the longitudinal direction so that a plurality of coupling grooves are formed at regular intervals.

The fixed contact 200 is formed to have a predetermined width and will be described later.

The fixed insulation tap plate 100 has a characteristic that it can be replaced with a domestically produced foreign insulator, and is formed under a fixed table cast with aluminum.

Here, the fixed insulation tap plate 100 is coupled to the fixing table by bolting or the like.

The fixed contact 200 according to the present invention is formed in the coupling groove of the fixed insulation tap plate 100 and it is a matter of course to use an insulating material.

The fixed contact 200 includes five tabs 210 in total, and five tabs are formed in a total of three sets.

Stability of the fixed contact 200 is maintained because the tab 210 is connected to the coil.

Here, the stationary contact 200 has a terminal hole for connecting the tab lead 220, so that the fixed contact 200 is connected to the coil tab and the lead wire so that electricity is applied.

The movable contact 300 according to the present invention is paired and two of the fixed contacts 200 are simultaneously in contact with each other, and the movable contact 300 is moved through the movable rack gear 410. Here, the fixed contact 200 varies in number.

Here, the movable contact 300 is in contact with the tabs so that the movable contact 300 can be in-out, so that one side of the movable contact 300 is in the in position and the other side of the movable contact 300 is out of the movable contact 300. As the movable contact 300 is moved through the movable rack gear 410, .

Here, the movable contact 300 is connected to two tabs of the fixed contact 200 by being brought into contact with the spring pressure, so that electricity is applied.

The gear box 400 according to the present invention includes a movable rack gear 410 for moving the movable contact 300 to the left and right and a pinion gear 420 interlocked with the movable rack gear 410 and rotated by a power source, .

The gear box 400 is fixedly coupled to the fixed tap insulating plate, and the movable rack gear 410 and the pinion gear 420 are provided for smooth rotation.

Here, the movable rack gear 410 corresponds to the length of the fixed tap insulating plate, and it is natural that an insulating material is used.

The movable rack gear 410 is meshed with the pinion gear 420 of the counterpart gear so that when the pinion gear 420 rotates, the movable rack gear 410 is linearly moved left and right, .

The driving shaft 450 is axially formed at the center of the pinion gear 420 so that the movable rack gear 410 engaged with the pinion gear 420 is moved by one tap when the driving shaft 450 rotates at a predetermined angle.

The drive shaft 450 is formed with a compression spring 455 therein so that the pinion gear 420 can be fixed in position.

The driving handle 500 according to the present invention is connected to the driving shaft 450 so that the driving shaft 500 is rotated to interlock the driving shaft 450. The moving rack gear 410 is moved, (410) is rotated.

Preferably, a plurality of the fixed contacts 200 are formed at regular intervals, and the movable contacts 200 can be variously transformed at the same time.

Preferably, the drive handle 500 and the drive shaft 450 are O-ring operated to maintain airtightness.

Here, the O-ring is assembled to the inside of the flange and the drive shaft 450, and serves as a hermetic seal to prevent the insulating oil from escaping to the outside. Meanwhile, the flange is welded to the transformer enclosure to assemble the drive shaft 450 and the drive handle 500.

Preferably, the eighth drive handle 500 is configured to automatically lock the locking pin once the locking pin has been disassembled after the locking pin has been formed and the locking pin has been removed. In particular, the range of the tabs 1 and 5 is not exceeded.

Next, a description will be given of an embodiment of a 30 kV no-load under-tapping ventilation of the present invention.

First, the fixed contact 200 has five tabs in total, and is installed based on the third tab.

Therefore, when the voltage is 100V, the variable ratio of the 2.5% voltage is formed to the right and left of each step at 100V in the third tap. That is, the second tab is -2.5%, the first tab is -5%, the fourth tab is 2.5%, and the fifth tab is + 5%. It is a matter of course that the above adjustment can be made in accordance with the requirements of the buyer of the transformer manufacturing site.

The method of the present invention first rotates the drive handle 500 at a predetermined angle after releasing the lock pin and moves to the fourth tab or the second tab. That is, when the drive handle 500 is moved, the voltage is increased and the voltage is lowered and then moved to the tab. And, after one tab movement, it becomes a lock function automatically.

Next, the movement by one tap is shifted to the left and right linear motion of the movable rack gear by the rotation of the pinion gear, and the function for preventing the rotation should be included so that it can move only within the tabs of No. 1 and No. 5.

As described above, rotating the plurality of rotating contacts equally is regarded as a basic technical specification, which is merely an example, and those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. It is to be understood that the true scope of protection of the present invention should be determined within the scope of the appended claims.

100: Fixed insulation plate
200: Fixed contact
210: Tab
220: Tab Lead
300: moving contact
400: gear box
410: Movable rack gear
420: pinion gear
450: drive shaft
455: Compression spring
500: drive handle

Claims (4)

In the no-load tap-changer,
A fixed insulating tab plate 100 formed to be long in the longitudinal direction and having a plurality of coupling grooves;
A plurality of fixed contacts 200 formed in the coupling groove of the fixed insulation tap plate 100;
A movable contact 300 made of a pair and contacting the fixed contact 200 simultaneously at two points;
A gear box 400 having a movable rack gear 410 and a pinion gear 420 for moving the movable contact 300;
A drive shaft 450 supporting the center of the gear box 400;
And a drive handle (500) for moving the drive shaft (450). The method according to claim 1,
Wherein a plurality of the fixed contacts (200) are formed at regular intervals, and various types of transformations are possible at the same time. The method according to claim 1,
The gear box (400)
And a pinion gear (420) connected to the rack gear, wherein the pinion gear (420) is connected to the rack gear. The method according to claim 1,
Wherein the drive handle (500) and the drive shaft (450) are O-ringed to maintain airtightness.

Images