KR20150037355A - Apparatus for acquiring vibration energy of power transformer - Google Patents

Apparatus for acquiring vibration energy of power transformer Download PDF

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Publication number
KR20150037355A
KR20150037355A KR20130116879A KR20130116879A KR20150037355A KR 20150037355 A KR20150037355 A KR 20150037355A KR 20130116879 A KR20130116879 A KR 20130116879A KR 20130116879 A KR20130116879 A KR 20130116879A KR 20150037355 A KR20150037355 A KR 20150037355A
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South Korea
Prior art keywords
energy
vibration
power transformer
units
rectifying
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KR20130116879A
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Korean (ko)
Inventor
구교선
권동진
우정욱
곽주식
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한국전력공사
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Priority to KR20130116879A priority Critical patent/KR20150037355A/en
Publication of KR20150037355A publication Critical patent/KR20150037355A/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/32—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from a charging set comprising a non-electric prime mover rotating at constant speed
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
    • H02N2/18—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing electrical output from mechanical input, e.g. generators
    • H02N2/186—Vibration harvesters
    • H02N2/188—Vibration harvesters adapted for resonant operation

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)

Abstract

The present invention relates to a device for acquiring vibration energy of a power transformer, which comprises: a plurality of energy acquisition units to convert vibration according to a plurality of frequencies generated from a power transformer into electrical energy; a plurality of rectification units to rectify the electrical energy converted by the energy acquisition units; and a charging unit to charge the electrical energy rectified by the rectification units.

Description

TECHNICAL FIELD [0001] The present invention relates to a vibration energy obtaining apparatus for a power transformer,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration energy obtaining apparatus for a power transformer, and more particularly, to a vibration energy obtaining apparatus for converting energy generated by vibration of a power transformer into electric energy, And more particularly to a vibration energy obtaining apparatus for a transformer.

In recent years, there has been a great deal of interest in the use of energy that is dumped from the surrounding area into available electrical energy.

These main energy sources are vibration, light, heat, electromagnetic wave, etc. This technology is used to acquire such energy. When the temperature of the contact point is different in a closed circuit composed of different kinds of metal junction, a thermoelectric effect (Seebeck Effect or Thermo-electric Effect or a technique using a piezoelectric effect in which electricity is generated when a pressure is applied to the piezoelectric element.

Piezoelectric effect is used to convert vibration or impact energy generated by a large rotating machine or structure into electric energy. Piezoelectric effect can also be used in obtaining energy by vibration of power transformer.

1 is a view showing a crystal structure of a piezoelectric element.

Referring to FIG. 1, when a tensile force or a compressive force is applied to a piezoelectric element (quartz crystal), the crystal structure is temporarily deformed to change the relative positions of + ions and - ions, thereby causing a polarization phenomenon. As a result, when a tensile force and a compressive force are applied to the piezoelectric element, electric fields opposite to each other are formed on both sides of the piezoelectric element.

A technique of connecting an electric circuit to a piezoelectric element using this principle and charging it with electric energy resulting from electric field generation is used.

Prior art related to the present invention is Korean Patent Laid-Open Publication No. 2013-0033223 (published on Mar. 03, 2013, entitled "Vibration Energy Collecting Apparatus of Frequency Increasing Conversion Type").

Since the conventional electric energy charging device was developed for the purpose of being installed on a road or a railway, it is configured to acquire an energy having a frequency of irregularity and a wide frequency range.

Therefore, there is no energy charging apparatus developed for obtaining the vibration energy of the power transformer, and there is a problem that the charging efficiency is low when the existing electric energy charging apparatus is used for the power transformer.

Conventionally, a method of converting an energy source discarded by using a piezoelectric element into electric energy has a problem that electric energy is generated by up-and-down motions, so that the charging efficiency is low because of high voltage and low current as compared with rotational motion.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a piezoelectric transformer in which a plurality of cantilevers designed to resonate in response to a vibration frequency of a plurality of piezoelectric elements and power transformers are modularized, And an object of the present invention is to provide a vibration energy obtaining apparatus for a power transformer capable of improving vibration energy charging efficiency of a power transformer.

According to an aspect of the present invention, there is provided an apparatus for acquiring vibration energy of a power transformer, comprising: a plurality of energy acquiring units for converting respective vibrations according to a plurality of frequencies generated in a power transformer into electric energy; A plurality of rectifying units for rectifying respective electric energy converted through the plurality of energy obtaining units; And a charging unit charging electric energy rectified through the plurality of rectifying units.

In the present invention, each of the plurality of energy acquisition units includes: a cantilever that resonates corresponding to a plurality of frequencies generated by the power transformer; And a piezoelectric element for converting the vibration of the cantilever into electric energy.

In the present invention, each of the cantilevers included in the plurality of energy acquisition units resonates in response to harmonic vibrations of an integral multiple of 120 Hz.

In the present invention, each of the plurality of energy acquisition units may further include an adjusting weight for adjusting the weight of the cantilever to assist the resonance.

In the present invention, the plurality of rectifying units rectify the respective electric energies by a bridge rectification method.

The present invention further includes a smoothing unit for smoothing the electric energy rectified through the plurality of rectifying units.

In the present invention, the plurality of charging units are configured to charge the charging unit other than the specific charging unit when the voltage charged in the specific charging unit exceeds the reference voltage.

According to the present invention, by converting the energy generated by the vibration of the power transformer, the waste energy can be recycled.

Further, according to the present invention, the vibration energy charging efficiency can be improved by modularizing a plurality of piezoelectric elements and a plurality of cantilevers, respectively, and can be easily replaced and used when a partial failure occurs.

In addition, since the present invention is installed in a transformer, unlike a vibration energy acquisition device installed on a road or a railroad, it is possible to generate electricity continuously for 24 hours and energy can be continuously charged.

1 is a view showing a crystal structure of a piezoelectric element.
2 is a view showing a hysteresis curve and a modification of the transformer iron core.
3 is a graph showing a measurement of the vibration frequency of the power transformer.
4 is a functional block diagram of an apparatus for acquiring vibration energy of a power transformer according to an embodiment of the present invention.
5 is a configuration diagram illustrating an energy acquisition unit of a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.
6 is a graph comparing an output of a rectifying unit and an output of a conventional single rectifying circuit in a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.
7 is a circuit diagram showing a rectifying unit of a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.
FIG. 8 is a flowchart illustrating a process of acquiring vibration energy through a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.

Hereinafter, an apparatus for acquiring vibration energy of a power transformer according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

FIG. 2 is a diagram showing a hysteresis curve and a modification of the transformer iron core. FIG. 2 (A) shows a hysteresis curve for the magnetic flux variation of the iron core according to the magnetic field strength, Fig.

The transformer is an apparatus for generating an alternating magnetic flux in the iron core by the alternating voltage applied to the high-voltage winding, and modifying the voltage by the electromagnetic induction action to supply the alternating voltage to the low-voltage winding.

Specifically, the iron core has a structure in which a steel sheet having a thickness of 2.3 mm to 3 mm is laminated. The material is a ferromagnetic material containing 0.5 to 5% of silicon in iron. When magnetic flux is introduced into the iron core and magnetized, A shape change occurs, which is called magnetic distortion or magnetostriction.

When a power source with a frequency of 60 Hz is applied to the transformer, the iron core is magnetized non-linearly as shown in Fig. 3 (A), and deformation of the iron core occurs as shown in Fig. 2 (B).

Since such deformation occurs irrespective of the direction of the magnetic flux, a harmonic vibration (120, 240, 360, 480 ...) of n times the frequency of the power source frequency of 120 Hz is generated.

Therefore, all transformers inevitably generate 120 Hz harmonic component vibration due to magnetostriction, and the generated vibration is transmitted to the transformer enclosure through the insulation or support structure of the transformer.

3 is a graph showing a measurement of the vibration frequency of the power transformer.

Referring to FIG. 3, the vibration measured in the power transformer enclosure does not include a vibration component other than the 120 Hz harmonic component, and the components below 1 kHz occupy the majority.

Therefore, in the case of a transformer, it is helpful to select and acquire only vibrational energy that oscillates at a frequency of 1 kHz or less to improve the efficiency of electric energy acquisition.

4 is a functional block diagram of an apparatus for acquiring vibration energy of a power transformer according to an embodiment of the present invention.

5 is a configuration diagram illustrating an energy acquisition unit of a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.

6 is a graph comparing an output of a rectifying unit and an output of a conventional single rectifying circuit in a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.

7 is a circuit diagram showing a rectifying unit of a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.

4 to 7, an apparatus for acquiring vibration energy of a power transformer according to an embodiment of the present invention includes an energy acquisition unit 100, a rectification unit 200, and a charging unit 300.

The energy acquisition unit 100 is a device that converts vibration according to a frequency generated by a power transformer into electric energy. In particular, in the present embodiment, And a plurality of energy acquisition units 120, 140, and 160 for conversion.

The number n of the energy acquisition units 100 according to the present embodiment can be changed corresponding to the oscillation frequency of the power transformer. As described above, in a power transformer having a power frequency of 60 Hz, vibration energy exists in an harmonic frequency component which is an integer multiple of 120 Hz, and n is set to 5 since most of the vibration energy appears in a component of 1 kHz or less.

Each of the plurality of energy acquisition units 120, 140, and 160 converts the vibrations of the cantilevers 124, 144, and 164 and the cantilevers 124, 144, and 164, which resonate corresponding to a plurality of frequencies generated in the power transformer, 146,166 for adjusting the weight of the piezoelectric elements 122, 142, 162 and the cantilevers 124, 144,

That is, in the present embodiment, instead of converting the vibration of the power transformer into electric energy and acquiring the vibration through the one energy acquisition unit 100, the plurality of energy acquisition units 120, 140, and 160 are configured by modularization, It is possible to efficiently collect energy according to the main vibration frequency of the power transformer.

Referring to FIG. 5, the energy acquisition unit of the vibration energy obtaining apparatus according to the present embodiment, which is mounted on the power transformer, includes a stationary magnet 180 at a lower portion of the energy- And the energy acquisition device 160 is fixed to the power transformer by the magnetic force of the fixed magnet 180. [

The plurality of energy acquisition devices 120, 140, and 160 are coupled to each other through the fixing screws 190 and fixed to the power transformer, so that the vibration of the power transformer is transmitted to the plurality of energy acquisition devices 120, 140 and 160 It can be delivered efficiently.

More specifically, a process of converting the vibration energy of the power transformer into the electric energy in the energy obtaining unit 100 will be described. Each of the plurality of cantilevers 124, 144, and 164 corresponds to a plurality of frequencies included in the vibration of the power transformer And repeats the reciprocating reciprocating motion.

Particularly, in this embodiment, the cantilevers 124, 144, and 164 are designed to resonate in correspondence to the vibration frequency of the power transformer. Specifically, the length, mass or the weight of the cantilevers 124, 144, 166 to adjust the energy acquisition frequency range of the cantilevers 124, 144, and 164.

That is, as the length of the cantilevers 124, 144, and 164 is reduced, the corresponding resonance frequency increases. As the mass of the cantilevers 124, 144, and 164 decreases, the corresponding resonance frequency increases. 144, and 164 are increased, the energy acquisition frequency range of the cantilevers 124, 144, and 164 can be adjusted by considering these factors.

Particularly, in this embodiment, the adjustment weights 126, 146, and 166 are located on the cantilevers 124, 144, and 164 in case the up and down movements of the cantilevers 124, 146, and 166 adjust the weight of the cantilevers 124, 144, and 164 to assist resonance.

The piezoelectric elements 122, 142 and 162 convert the energy in the harmonic component of a specific frequency (120 Hz in this embodiment) of the power transformer into electric energy based on the vibrations of the cantilevers 124, 144 and 164.

The rectifying unit 200 rectifies the converted electric energy through the energy obtaining unit 100.

That is, since the electric energy output from the energy acquisition unit 100 is an AC component, it is rectified as a DC component through the rectifying unit 200.

Particularly, if the electric energy output from the plurality of energy acquisition units 120, 140, and 160 is designed to pass through the same rectifier, the electric energy output from each of the energy acquisition units 120, 140, The present embodiment includes a plurality of rectifying sections 220, 240, and 260 for rectifying the respective electric energy output from the energy acquisition sections 120, 140, and 160, respectively.

The output loss of the converted electric energy can be prevented by constructing the plurality of rectifying sections 220, 240 and 260 according to the vibration frequency of the power transformer.

Referring to FIG. 6, when the output of the vibration energy obtaining apparatus of the power transformer according to the embodiment of the present invention passes through the rectifying unit and the output of the conventional single rectifying circuit is compared, the solid line shows the rectifying units 220, 240, 260, respectively, and the dotted line represents the output of the electric energy rectified through the single rectifying circuit.

6, when the electric energy output from the plurality of energy acquisition units 120, 140, and 160 is rectified through the plurality of rectification units 220, 240, and 260, respectively, the electric energy is not canceled each other It is confirmed that the output efficiency is higher than the solid line.

In this embodiment, the plurality of rectifying sections 220, 240, and 260 rectify the respective electric energies by the bridge rectification method, thereby improving the efficiency of rectifying the energy of the AC component.

The smoothing unit 300 is an apparatus for smoothing the electric energy rectified through the plurality of rectifying units 220, 240, and 260, and can be smoothly smoothed through a capacitor.

That is, since the direct current component of the electric energy rectified by the rectifying unit 200 is a ripple-including pulsation, the present embodiment further includes the smoothing unit 300 to convert the rectified electric energy into direct current, .

Also, the smoothing unit 300 according to the present embodiment is not limited to the capacitors, and may include various other known and unknown devices and circuits.

The charging unit 400 charges the smoothed electric energy through the smoothing unit 300.

Particularly, in the present embodiment, the charging unit 400 includes a plurality of charging units 400, and charges the charging unit 400 other than the specific charging unit 400 with electric energy when the voltage charged in the specific charging unit 400 exceeds the reference voltage.

Referring to the process of charging the plurality of chargers 400 through FIG. 7, the smoothed electrical energy is firstly charged into the first charger 420 through the smoothing unit 300.

When the charged voltage becomes equal to or higher than the reference voltage, the switch 350 is controlled to change the path so that the second charging unit 440 is charged with electrical energy by measuring the voltage charged in the first charging unit 420 , Thereby preventing overheating due to overcharging of the charger unit (400).

Although the plurality of charging units 400 include the first charging unit 420 and the second charging unit 440 in the above description, the number of the charging units 400 can be freely changed.

In addition, when a separate lamp (not shown) is connected to each of the plurality of chargers 400 and the lamp is charged by the reference voltage, the lamp may be operated so that the operator can visually confirm the lamp.

The vibration energy obtaining apparatus of the power transformer according to the present embodiment increases the energy acquisition effect as it is widely distributed in the transformer enclosure. However, reducing the contact surface between the enclosure and the outside air may degrade the cooling performance of the power transformer.

In this regard, the vibration of the power transformer mainly occurs on the side surface, and occurs more intensively in the flat portion than in the elliptical bent portion. Therefore, when the vibrational energy obtaining apparatus according to this embodiment is installed between the braces on the side of the transformer, It is possible to maximize the acquisition efficiency of the vibration energy while minimizing the performance deterioration.

FIG. 8 is a flowchart illustrating a process of acquiring vibration energy through a vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention.

Referring to FIG. 8, a process of acquiring vibration energy through the vibration energy obtaining apparatus of a power transformer according to an embodiment of the present invention will be described. First, a plurality of energy acquiring units 100 acquire vibration energy The vibration according to the frequency is converted into electrical energy (S10).

That is, in the present embodiment, instead of converting the vibration of the power transformer into electric energy and acquiring the vibration through the one energy acquisition unit 100, the plurality of energy acquisition units 120, 140, and 160 are configured by modularization, It is possible to efficiently collect energy according to the main vibration frequency of the power transformer.

Concretely, in the above-described step S10, the plurality of cantilevers 124, 144, and 164 resonate corresponding to a plurality of frequencies generated in the power transformer, and the piezoelectric elements resonate with the vibrations of the plurality of cantilevers 124, To electrical energy.

Next, the plurality of rectifying units 200 rectify each of the converted electric energy through the plurality of energy obtaining units 100 (S20).

Particularly, if the electric energy output from the plurality of energy acquisition units 120, 140, and 160 is designed to pass through the same rectifier, the electric energy output from each of the energy acquisition units 120, 140, The present embodiment includes a plurality of rectifying sections 220, 240, and 260 for rectifying the respective electric energy output from the energy acquisition sections 120, 140, and 160, respectively.

Next, the smoothing unit 300 smoothes the electric energy rectified through the plurality of rectifying units 200 (S30), and the charging unit 400 charges the smoothed electric energy (S40).

According to the present embodiment, by converting the energy generated by the vibration of the power transformer, the waste energy can be recycled.

In addition, the present embodiment can improve the charging efficiency of vibration energy by constituting a plurality of piezoelectric elements and a plurality of cantilevers by modularizing them, respectively, and can be easily replaced and used when a partial failure occurs.

In addition, since the present embodiment is installed in a transformer, unlike a vibration energy obtaining apparatus installed on a road or a railroad, it is possible to generate electricity continuously for 24 hours and energy can be continuously charged.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, I will understand. Accordingly, the true scope of the present invention should be determined by the following claims.

100: energy acquisition unit 120: first energy acquisition unit
122, 142, 162: piezoelectric element 124: first cantilever
126: first adjustment weight 144: second cantilever
146: second adjusting weight 164: nth cantilever
166: nth adjustment weight 180: stationary magnet
190: fixing screw 200: rectifying part
220: first rectification part 240: second rectification part
260: nth rectification part 300: Smooth part
400: live part 420: first live part
440: Second charging section

Claims (7)

A plurality of energy acquisition units for converting respective vibrations according to a plurality of frequencies generated in the power transformer into electric energy;
A plurality of rectifying units for rectifying respective electric energy converted through the plurality of energy obtaining units; And
And a charging section for charging electric energy rectified through the plurality of rectifying sections
Wherein the vibration energy acquisition device comprises: The method according to claim 1,
Each of the plurality of energy acquisition units includes a cantilever that resonates corresponding to a plurality of frequencies generated by the power transformer; And
A piezoelectric element for converting the vibration of the cantilever into electric energy;
And a vibration energy obtaining device for obtaining the vibration energy of the power transformer. 3. The method of claim 2,
Wherein each of the cantilevers included in the plurality of energy acquisition units resonates corresponding to a harmonic vibration of an integer multiple of 120 Hz. The method of claim 3,
Wherein each of said plurality of energy acquisition units further comprises an adjusting weight for adjusting resonance of the cantilever by adjusting the weight of said cantilever. The method according to claim 1,
Wherein the plurality of rectifying sections rectify the respective electric energies by a bridge rectification method. The method according to claim 1,
Further comprising a smoothing unit for smoothing the electric energy rectified through the plurality of rectifying units. The method according to claim 1,
Wherein the charging unit is composed of a plurality of units, and when the voltage charged in the specific charging unit exceeds a reference voltage, the charging unit charges the charging unit except for the specific charging unit.
KR20130116879A 2013-09-30 2013-09-30 Apparatus for acquiring vibration energy of power transformer KR20150037355A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017043852A1 (en) * 2015-09-11 2017-03-16 주식회사 에이엠씨에너지 Power supply circuit using piezoelectric transformer
KR20180065662A (en) * 2016-12-08 2018-06-18 한전케이디엔주식회사 Sensor for detecting vibration

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017043852A1 (en) * 2015-09-11 2017-03-16 주식회사 에이엠씨에너지 Power supply circuit using piezoelectric transformer
KR20180065662A (en) * 2016-12-08 2018-06-18 한전케이디엔주식회사 Sensor for detecting vibration

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