KR101497646B1 - Apparatus for automatically switching a first side coil tab - Google Patents

Abstract

The present invention relates to a power tap transformer primary tap automatic switching device, which measures the secondary voltage of the power transformer and, when compensation of the secondary voltage of the power transformer is required, A control unit for determining a moving position and controlling the motor to move the moving tab to the determined moving position of the moving tab, the moving tab being located on the primary side of the power transformer; And a control unit which is connected to the fixed tap of the plurality of fixed taps connected to the power transformer at the moved position to change the turn ratio between the primary side and the secondary side of the power transformer And a moving tap for compensating the secondary voltage of the power transformer by the moving tap.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a power transformer primary tap automatic switching device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic tap switching device for a power transformer, and more particularly, to a tap automatic switching device capable of automatically adjusting a secondary tap voltage of a power transformer by automatically switching a primary tap in a load- .

Generally, extra high voltage (765 kV, 345 kV, 154 kV) produced by the power plant is supplied to the substation by the transmission line. In the substation, the high voltage is lowered to 22900 volts (= 13200 phase voltage) Part of the extra high voltage supplied to the substation is lowered to the easy-to-use voltage of 220/380 volts through the pole transformer and the gas-phase transformer attached to the pole and supplied to houses, shops and small-scale factories do.

In the transformer used for such power supply, the secondary voltage changes depending on the load fluctuation, the length of the transmission line, and the like. In order to compensate for such secondary side voltage variation, conventionally, the secondary side voltage variation is compensated by switching the tab on the secondary side of the transformer.

However, in the conventional method, the secondary side tap had to be switched manually by inserting the hand into the transformer with the primary winding side cut-out switch turned off. As a result, there has been a problem that the electric power supplied to the electric power consumers electrically connected to the transformer during the manual switching operation is interrupted and the electric power is interrupted. In addition, by manually inserting a hand into the transformer and switching the tabs, foreign substances such as sweat, dust, and rainwater enter the transformer, causing the dielectric oil inside the transformer to deteriorate and transformer failure and life span .

Accordingly, it is an object of the present invention to provide a device capable of automatically switching a transformer tap.

Other objects of the present invention will become readily apparent from the following description of the embodiments.

According to another aspect of the present invention, there is provided an automatic tap switching apparatus for a power transformer, comprising: a main transformer for measuring a secondary voltage of the power transformer; A control unit for determining a moving position of the moving tab for compensating the secondary side voltage and controlling the motor to move the moving tab to the determined moving position of the moving tab when the compensation of the secondary side voltage is required, Located on the primary side of the power transformer; And a control unit which is connected to the fixed tap of the plurality of fixed taps connected to the power transformer at the moved position to change the turn ratio between the primary side and the secondary side of the power transformer And a moving tap for compensating the secondary voltage of the power transformer by the moving tap.

As described above, the present invention can automatically switch the transformer tap.

1 shows a state in which a tap switching device according to a preferred embodiment of the present invention is installed in a transformer.
Fig. 2 is a view showing in detail the mutual arrangement of the fixed tab, the insulating member, and the moving tab in the direction of the transformer viewed from the high-voltage line side of Fig.
3 is a functional block diagram of the control unit of Fig.
4 is a flowchart illustrating a tap switching method according to an exemplary embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for like elements in describing each drawing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, .

On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention.

The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

The present invention can automatically compensate for the voltage fluctuation of the secondary side of the power transformer by adjusting the turns ratio of the primary side and the secondary side of the power transformer automatically when the secondary side voltage of the power transformer fluctuates.

Hereinafter, a tap switching device according to a preferred embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. Hereinafter, in order to make the gist of the present invention clear, a description of well-known matters will be omitted or simplified. 1 shows a state in which a tap switching device according to a preferred embodiment of the present invention is installed in a transformer. Fig. 2 is a view showing in detail the mutual arrangement of the fixed tab, the insulating member, and the moving tab in the direction of the transformer viewed from the high-voltage line side of Fig. 3 is a functional block diagram of the control unit of Fig.

Referring to FIG. 1, the power transformer 10 may include a primary side 11 and a secondary side 12. The power transformer 10 can reduce the voltage supplied to the primary side 11 through the high-voltage line 20 and provide the reduced voltage to the secondary side 12.

The primary side 11 is provided with a plurality of fixed tabs, for example, a first fixed tab 700a and a second fixed tab, which are connected to the primary side 11 windings and form a predetermined turn ratio with the secondary side 12, 700b, a third fixing tab 700c, and a fourth fixing tab 700d. Hereinafter, for convenience of explanation, it is assumed that there are four fixed tabs, but the present invention does not limit the number of fixed tabs. An insulating member, for example, a first insulating member 800a, a second insulating member 800b, and a third insulating member 800c may be provided between the upper and lower fixing tabs.

The movable tab 210 is connected to one of the fixed tabs 700a, 700b, 700c, and 700d on the primary side at the moved position while moving up and down, The voltage of the secondary side 12 of the power transformer can be made constant by converting the turn ratio between the side 12 of the power transformer. That is, it is possible to compensate the voltage fluctuation of the secondary side 12 of the power transformer. The moving tab 210 includes a hollow main body 211 and a contact portion 212 protruding outside the main body 211. The main body 211 can transmit the voltage on the high-voltage line 20 to the fixing tab through the contact portion 212. [

Referring to FIG. 2, the moving tab 210 may include a first contact portion 212a and a second contact portion 212b that are in close contact with both sides of the fixing tab 700a. The first contact portion 212a and the second contact portion 212b may have a rounded protrusion opposed to the rounded groove on the fixing tab 700a on the surface opposed to the fixing tab 700a. This increases the contact surface between the first contact portion 212a and the second contact portion 212b and the fixing tab 700a to decrease the contact resistance between the first contact portion 212a and the second contact portion 212b and the fixing tab 700a And the first contact portion 212a and the second contact portion 212b can be tightly fixed to the fixing tab 700a more stably. The present invention can provide a large amount of fixing tabs to compensate the secondary side 12 voltage more precisely. At this time, since the interval between the fixing tabs is narrow, the primary side may be short-circuited by the contact portion 212. In order to prevent this, an insulating member (a first insulating member 800a, a second insulating member 800b, and a third insulating member 800c) may be provided between upper and lower fixing tabs. Both side surfaces of the insulating member have rounded surfaces protruding outward, and both side surfaces thereof can be located on the outermost outermost side of the fixing tab. As a result, the first contact portion 212a and the second contact portion 212b are separated from each other by the surface located at the outermost outermost side of the fixing tab when the contact portion 212 is moved up and down, have. 2 shows a state in which the first contact portion 212a and the second contact portion 212b are separated from each other by the second insulating member 800b while the contact portion 212 is moving from the first fixing tab 700a to the third fixing tab 700c Respectively.

1, the main body 211 of the moving tab 210 accommodates the guide rod 100 in the inside thereof, and can move up and down along the guide rod 100. The guide rod 100 includes a receiving portion 110 extending to one side, and the receiving portion 110 receives the high-voltage line 20 at one end. With this structure, the voltage on the high-voltage line 20 is transmitted to the primary side 11 of the power transformer 10 through the guide rod 100, the moving tab body 210, the contact portion 210, Lt; / RTI >

The control unit 500 may include a voltage measuring unit 510, a tap determining unit 520, and a motor control unit 530.

The voltage measuring unit 510 can measure the voltage of the secondary side 12 using the output value of the voltage sensing unit 600 that senses the voltage of the secondary side 12 of the power transformer 10.

The tap determining unit 520 can determine the fixed tap to be connected to the moving tab 210 based on the voltage of the secondary side 12 measured by the voltage measuring unit 510. [ At this time, the tap determining unit 520 can determine the turn ratio to compensate for the voltage drop of the secondary side 12, and determine the fixed tab that can most suit the turn ratio.

The motor control unit 530 can move the moving tab 210 to the determined fixed tap position by driving the motor 310. [

The motor 310 can rotate the shaft 311 in the clockwise and counterclockwise directions. The three-dimensional cam 320 may be fixed to the shaft 311 of the motor 310. A spiral inclined groove 321 may be formed on the outer surface of the three-dimensional cam 320. [ The stereoscopic cam 320 can rotate along the motor shaft 311. [ A hollow moving rod 900 may be positioned outside the stereoscopic cam 320. An upper portion of the moving rod 900 may be fixed to a lower portion of the moving tab body 211. The moving rod 900 accommodates the three-dimensional cam 320 on the inner side, and a protrusion 910 may be provided on the inner peripheral surface thereof. The protrusion 910 is inserted into the inclined groove 321 and moves up and down along the inclined groove 321 when the stereoscopic cam 320 rotates so that the movable bar 900 can move up and down. The movable tab 210 can be moved up and down by the up and down movement of the movable rod 910. [ It is preferable that the inclined grooves 321 are formed so that the movable tab 210 can be moved from the present position to the upper or lower fixed tab by one rotation of the cubic cap 320 during design. 1, when the motor moves clockwise, the moving rod 900 moves upward along the inclined groove 321, and when the motor rotates in the counterclockwise direction, the moving rod 900 can be moved downward.

The reflection plate 410 may be provided on the outer surface of the stereoscopic cam 320. An optical sensor 420 may be installed at a position opposite to the reflection plate 410. The light sensor 420 includes a light emitting element and a light receiving element, and the light receiving element can collect an amount of the light emitted from the light emitting element reflected through the reflection plate 410. The reflection plate 410 can be returned to the initial position at each initial rotation of the stereoscopic cam 320, In such a structure, the output value of the light receiving element at the initial position of the reflection plate 410 can be maximized.

The tab determining unit 520 can determine the number of revolutions of the stereoscopic cam 320 when the movement tab 210 determines the number of revolutions of the motor shaft when determining the fixed tab to be connected. The rotational direction of the motor shaft 311 can be determined in accordance with the moving direction of the moving tab 210. [ The motor control unit 530 can control the motor 310 so that the motor shaft 311 can be rotated by the determined rotation direction and the determined number of revolutions. At this time, the motor control unit 530 counts the number of rotations of the motor shaft 311 based on the output value of the optical sensor 420, and controls the motor shaft 311 to rotate by the determined number of rotations based on the counted number of rotations The motor can be controlled.

Hereinafter, a tap automatic switching method according to a preferred embodiment of the present invention will be described with reference to FIGS. 1 to 4 attached hereto. 4 is a flowchart illustrating a tap switching method according to an exemplary embodiment of the present invention. The description of the foregoing is omitted or simplified. By the following explanation, the configuration of the tap automatic switching device seen earlier can be made more clear.

First, the voltage measuring unit 510 may measure the voltage of the secondary side 12 using the output value of the voltage sensing unit 600 that senses the voltage of the secondary side 12 of the power transformer 10 (S41).

The tap determining unit 520 can determine the fixed tap to which the moving tab 210 is connected based on the voltage of the secondary side 12 measured by the voltage measuring unit 510 (S42).

Then, the tap determining unit 520 can calculate the number of revolutions of the motor shaft necessary to connect the moving tab 210 to the fixed tap determined in S42 (S43). For example, when the moving tab 210 is moved from the first fixing tab 700a to the third fixing tab 700b, the rotation number " 2 " may be determined. The tap determining unit 520 can determine the direction of rotation of the motor according to whether the moving tab 210 moves upward or downward. For example, when the motor rotates in the clockwise direction in the structure shown in FIG. 1, when the moving rod 900 moves upward along the inclined groove 321 and the motor rotates counterclockwise, The moving rod 900 moves downward along the first fixing tab 700a to the third fixing tab 700b so that the tab determining portion 520 can determine the rotating direction of the motor in the counterclockwise direction have.

The motor control unit 530 can control the motor 310 so that the motor shaft 311 can be rotated by the motor rotation direction and the motor rotation speed determined by the tap determination unit 520 (S44). At this time, the motor control unit 530 may count the number of rotations of the motor using the output value of the optical sensor 420, and rotate the motor shaft by the determined number of rotations of the motor shaft based on the counted value.

It will be apparent to those skilled in the relevant art that various modifications, additions and substitutions are possible, without departing from the spirit and scope of the invention as defined by the appended claims. The appended claims are to be considered as falling within the scope of the following claims.

10: Power Transformer
11: Power transformer primary side
12 Power transformer secondary side
20: High voltage line
100: guide rod
110:
210: Go tab
211: Body
212:
212a: first contact
212b:
310: motor
311: Motor shaft
320: stereoscopic cam
321:
410: reflector
420: Light sensor
500:
510: Voltage measuring section
520:
530: Motor control unit
600: voltage sensing unit
700a: first fixing tab
700b: second securing tab
700c: third fixing tab
700d: fourth fixing tab:
800a: first insulating member
800b: second insulating member
800c: third insulating member
900:
910:

Claims (5)

A power transformer primary tap automatic switching device comprising:
Wherein the control unit measures the secondary voltage of the power transformer and determines the moving position of the moving tab for compensating the secondary voltage when the secondary voltage of the power transformer is required, A moving part for moving the moving tab to a position of the power transformer;
And a power transformer connected to the fixed tap of the plurality of fixed taps connected to the power transformer at the moved position to change the turn ratio between the primary side and the secondary side of the power transformer by moving up and down under the control of the control unit A moving tab for compensating for a secondary voltage of the power transformer;
A three-dimensional cam connected to a shaft of the motor and having a spiral inclined groove formed on an outer surface thereof; And
Further comprising a moving rod which receives the stereoscopic cam on an inner side thereof and has a protruding portion inserted into the inclined groove on an inner side thereof, wherein the protruding portion moves up and down along the inclined groove when the stereoscopic cam is rotated,
A moving tab is fixed to the upper side of the moving rod,
Wherein the moving tab moves up and down according to the upward and downward movement of the moving rod. delete The method according to claim 1,
A reflection plate attached to an outer peripheral surface of the three-dimensional cam; And
Further comprising an optical sensor disposed at a position opposite to the reflection plate,
Wherein the control unit calculates the number of revolutions of the motor for compensating the secondary voltage of the power transformer and compensates the secondary voltage of the power transformer by rotating the motor by the number of revolutions for the compensation,
Wherein the control unit counts the number of revolutions of the motor by using an amount of light reflected by the optical sensor reflected through the reflector. The method of claim 3,
Wherein the movable tab includes a first contact portion and a second contact portion that are in close contact with both sides of the fixed tab, and wherein the first contact portion and the second contact portion are formed on a surface facing the fixed tab, Wherein the automatic tap switching device is provided with a true surface. 5. The method of claim 4,
Wherein the fixing tabs have rounded surfaces that are protruded outward from both sides of the plurality of fixing tabs, the both side surfaces being located at the outermost periphery of the fixing tabs, Thereby preventing a short circuit between neighboring fixed tabs.

Images