KR102043209B1 - Energy system capable of storing unused power operation method thereof - Google Patents

Abstract

The present invention relates to an energy system capable of storing unused electric power and a method of operating the same, and more particularly, an unused electric power capable of storing and utilizing low quality energy produced by a turbo machine before being connected to a grid. It relates to an energy system capable of storing and an operation method thereof. An energy system capable of storing unused power for this purpose includes a turbo machine for producing mechanical energy; A generator positioned at the rear of the turbo machine and converting the mechanical energy produced by the turbo machine into electrical energy; A grid connected to the generator; An energy storage system connected to the generator; A first switch for controlling a connection between the generator and the grid; A second switch for regulating a connection between the generator and the energy storage unit; And a control unit controlling opening and closing of the first switch and the second switch.

Description

Energy system capable of storing unused power and its operation method {ENERGY SYSTEM CAPABLE OF STORING UNUSED POWER OPERATION METHOD THEREOF}

The present invention relates to an energy system capable of storing unused electric power and a method of operating the same, and more particularly, an unused electric power capable of storing and utilizing low quality energy produced by a turbo machine before being connected to a grid. It relates to an energy system capable of storing and an operation method thereof.

A turbo machine is a mechanical device that obtains rotational force by impulse or reaction force by using a flow of a compressive fluid such as steam or gas, and includes a gas turbine using a hot combustion gas.

The gas turbine is a power engine that mixes and burns compressed air and fuel compressed in a compressor, and rotates the turbine with hot gas generated by combustion. Gas turbines are used to drive generators, aircraft, ships and trains.

Gas turbines generally include compressors, combustors, and turbines. The compressor sucks and compresses the outside air and delivers it to the combustor. The compressed air in the compressor is at high pressure and high temperature. The combustor mixes and combusts compressed air and fuel introduced from the compressor. The combustion gases generated by the combustion are discharged to the turbine. The combustion gas causes the turbine to rotate, which generates power. The generated power is used in various fields such as power generation and driving of mechanical devices.

On the other hand, the energy produced by a turbomachine, such as a gas turbine, the generator is not connected to the grid below a certain power frequency, at this time, there is a problem that the energy produced is not used.

In addition, on the contrary, the generator is connected to the grid to use energy, and after that, the turbo machine is stopped so that the energy generated when the generator is disconnected from the grid is not used.

Accordingly, there is a demand for development of an energy system and an operation method capable of improving energy efficiency by improving these problems.

Republic of Korea Patent Publication No. 10-179560

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an energy system and an operation method capable of storing and utilizing low quality energy produced by a turbomachine.

Specifically, energy generated when the generator is disconnected from the grid, that is, until the turbo machine is started and reaches a preset power frequency or when the turbo machine is stopped and becomes lower than the preset power frequency may be stored. To provide an energy system and a method of operation thereof.

These and other objects and advantages of the present invention will become apparent from the following description of preferred embodiments.

The object is a turbo machine for producing mechanical energy; A generator positioned at the rear of the turbo machine and converting the mechanical energy produced by the turbo machine into electrical energy; A grid connected to the generator; An energy storage system connected to the generator; A first switch for controlling a connection between the generator and the grid; A second switch for regulating a connection between the generator and the energy storage unit; And a control unit for controlling the opening and closing of the first switch and the second switch; can be achieved by an energy system capable of storing unused power.

The turbo machine may include a gas turbine or a steam turbine.

The energy storage unit may be a battery, and specifically, may be a secondary battery, and more specifically, at least one selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries, and lithium polymer batteries. Can be.

The controller may control to open the first switch and close the second switch below the preset power frequency, and close the first switch and open the second switch when the preset power frequency is reached. The set power frequency may be a value in the range of 50 to 60 Hz.

The controller may determine whether the power frequency fluctuates for 10 seconds when the preset power frequency is reached, and if the power frequency maintains the preset power frequency, closes the first switch and controls the second switch to be opened. Do.

In addition, the energy storage unit may include a power conditioning system (PCS) that changes the electrical characteristics of the power received from the generator.

In addition, the object is a first step of producing mechanical energy through a turbo machine; A second step of converting the produced mechanical energy into electrical energy; And a third step of controlling opening and closing of the first switch and the second switch through the control unit to transfer the converted electric energy to the grid or the energy storage unit.

The turbomachine of the first stage may include a gas turbine or a steam turbine.

The energy storage unit of the third step may be a battery, specifically, may be a secondary battery, and more specifically, selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries, and lithium polymer batteries. It may be at least one.

The controller of the third step may control to open the first switch and close the second switch when the preset power frequency is lower, and close the first switch and open the second switch when the preset power frequency is reached. In this case, the preset power frequency may be a value within a range of 50 to 60 Hz.

The controller may determine whether the power frequency fluctuates for 10 seconds when the preset power frequency is reached, and if the power frequency maintains the preset power frequency, closes the first switch and controls the second switch to be opened. Do.

In addition, the energy storage unit may include a power conditioning system (PCS) that changes the electrical characteristics of the power received from the generator.

In addition, the third step may include changing an electrical property before transferring the converted electrical energy to the energy storage.

In addition, the object is a step of producing mechanical energy through a turbo machine; Converting the produced mechanical energy into electrical energy; And a step (C) of controlling opening and closing of the first switch and the second switch through the control unit to transfer the converted electric energy to the grid or the energy storage unit. It can be achieved by a readable recording medium.

The turbo machine of step A may include a gas turbine or a steam turbine.

The energy storage unit of step C may be a battery, and specifically, may be a secondary battery, and more specifically, at least one selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries, and lithium polymer batteries. It can be either.

The control unit of step C may control to open the first switch and close the second switch below the preset power frequency, close the first switch and open the second switch when the preset power frequency is reached. In this case, the preset power frequency may be a value within a range of 50 to 60 Hz.

The controller may determine whether the power frequency fluctuates for 10 seconds when the preset power frequency is reached, and if the power frequency maintains the preset power frequency, closes the first switch and controls the second switch to be opened. Do.

In addition, the energy storage unit may include a power conditioning system (PCS) that changes the electrical characteristics of the power received from the generator.

Also, the step C may include changing electrical characteristics before transferring the converted electrical energy to the energy storage unit.

According to the present invention, it is possible to store and utilize the energy of the low quality produced by the turbo machine has the effect of improving the energy efficiency.

Specifically, it occurs in an acceleration section that reaches a constant speed state (connected to the grid) from an idle condition (a state in which the compressor can be driven only by the output of the turbine) during startup of a turbomachine including a gas turbine or a steam turbine. The low-quality power is stored in the energy storage and has the effect to utilize it.

In addition, the energy generated when the turbo machine stops and the connection with the grid is lost can also be stored.

However, the effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a view schematically showing a conventional energy system.
2 is a view schematically showing an energy system according to an embodiment of the present invention.
3 is a view schematically showing a startup sequence of a gas turbine.
4 is a view schematically showing an operating state of the energy system of FIG. 2.
5 is a view schematically showing an operating state of the energy system of FIG. 2.

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings of the present invention. These examples are only presented by way of example only to more specifically describe the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples. .

Also, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, and in the case of conflict, the specification including definitions The description of will prevail.

In the drawings, parts irrelevant to the description are omitted to clearly describe the proposed invention, and like reference numerals designate like parts throughout the specification. In addition, when a part "contains" a certain component, this means that the component may further include other components, without excluding other components, unless specifically stated otherwise. In addition, the "unit" described in the specification means one unit or block that performs a specific function.

In each step, an identification code (first, second, etc.) is used for convenience of description, and the identification code does not describe the order of each step, and each step does not explicitly describe a specific order in context. It may be carried out in a different order than described above. That is, each step may be performed in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

1 is a schematic view of an energy system including a conventional gas turbine, and FIG. 2 is a schematic view of an energy system including a gas turbine according to an embodiment of the present invention. Referring to FIGS. 1 and 2, an energy system capable of storing unused power according to an embodiment of the present invention includes a turbo machine 10 for producing mechanical energy; A generator 20 located at the rear end of the turbo machine 10 and converting the mechanical energy produced by the turbo machine 10 into electrical energy; A grid 30 connected with the generator 20; An energy storage system 40 connected to the generator 20; A first switch 50 for regulating the connection between the generator 20 and the grid 30; A second switch 60 which regulates a connection between the generator 20 and the energy storage unit 40; And a controller 70 that controls opening and closing of the first switch 50 and the second switch 60.

According to the present invention, before the generator 20 and the grid 30 are connected, the low quality energy produced by the turbo machine 10 may be stored and utilized, thereby improving energy efficiency. Specifically, during start-up of the turbomachine 10 including the gas turbine or the steam turbine, the idle condition (the state in which the compressor can be driven only by the output of the turbine) to the constant speed state (the state connected with the grid 30) The low-quality power generated in the acceleration period to reach has an effect that can be stored and utilized in the energy storage unit 40. In addition, the turbo machine 10 is stopped, and the energy generated when the connection with the grid 30 is dropped has an effect that can also be stored. That is, the present invention may store and utilize the energy generated when the generator 20 and the grid 30 are not connected after the turbo machine 10 is started or stopped.

The turbo machine 10 is a device for producing mechanical energy and may include a gas turbine or a steam turbine. 2 illustrates an example of a turbo machine 10 including a gas turbine, and will be described with reference to the drawing. The gas turbine is a power engine that mixes and burns compressed air and fuel compressed in the compressor 11, and rotates the turbine 13 with a high temperature gas generated by combustion. In general, the gas turbine is a compressor 11, a combustor. 12 and the turbine 13. The compressor 11 inhales and compresses the outside air to bring it into a state of high pressure and high temperature, and delivers it to the combustor 12. The combustor 12 mixes and combusts compressed air and fuel introduced from the compressor 11, and the combustion gas generated by the combustion is discharged to the turbine 13. The turbine 13 is rotated by the combustion gas, through which power is generated.

The generator 20 is connected to the turbo machine 10 to convert the mechanical energy generated by the turbo machine into electrical energy. The generator 20 is electrically connected to the grid 30 and the energy storage 40 to direct the converted electrical energy to the grid 30 or the energy storage 40. At this time, the first switch 50 and the second switch 60 are installed at the rear end of the branch point A, and the first switch 50 interrupts the connection between the generator 20 and the grid 30. The second switch 60 interrupts the connection between the generator 20 and the energy storage unit 40.

The energy storage system (ESS) 40 stores electrical energy converted by the generator 20, and may use a battery, and the battery may be a secondary battery. The secondary battery is not particularly limited, and various known ones can be used, and the secondary battery is preferably at least one selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries, and lithium polymer batteries.

The controller 70 controls the opening and closing of the first switch 50 and the second switch 60. FIG. 3 is a diagram schematically illustrating a start sequence of a gas turbine (when the power frequency is 60 Hz). The controller 70 will be described in detail with reference to FIG. 3. As shown in FIG. 3, the starting of the gas turbine may be divided into seven stages. That is, 1) turning, 2) GT start, 3) Purge, 4) Ignition, 5) Acceleration, 6) Synchronization, and 7) Load up. At this time, in step 5) the external power supply is cut off, the fuel is increased by increasing the amount of fuel, and in step 6) the switch is closed between the generator 20 and the grid 30. Therefore, in the related art, power generated until the generator 20 and the grid 30 are connected is not utilized and is discarded. The present invention includes an energy storage unit 40 in order to utilize the wasted power, and stores the low-quality energy in the energy storage unit 40 through the control unit 70. The stored energy can later be recycled in several ways.

Specifically, the control unit 70 controls to open the first switch 50 and close the second switch 60 below the preset power frequency, and closes the first switch 50 when the preset power frequency is reached. The control to open the second switch 60. The preset power frequency is specified for each country, and may be a value within a range of 50 to 60 Hz, and in Korea, 60 Hz. For reference, the power frequency is defined by Equation 1 below, and since the number of poles is generally used in the case of a gas turbine or a steam turbine, when the frequency is 60 Hz, the rotation speed of the generator 20 is 3600 Rpm.

[Equation 1]

Frequency (Hz) = Generator Speed (Rpm) X Generator Poles (p) / 120

That is, as shown in FIG. 4, by controlling only the second switch 60 to be closed below the preset power frequency, the conventionally discarded power may be stored in the energy storage unit 40. When the frequency is reached, the second switch 60 is opened and only the first switch 50 is closed so that the generated power is transferred to the grid 30.

At this time, the controller 70 preferably determines whether the predetermined power frequency has been reached for a predetermined time. For example, when the preset power frequency is reached, the controller 70 determines whether the power frequency is changed for 10 seconds, and when the power frequency is synchronized with the preset power frequency for 10 seconds, closes the first switch. By controlling to open the second switch, the energy storage operation is interrupted.

On the other hand, the front end of the energy storage unit 40 may include a PCS (Power Conditioning System) 80, such as a converter to change the electrical characteristics (AC / DC, voltage, frequency) of the power received from the generator 20. have.

Next, a method of operating an energy system capable of storing unused power will be described. In the description, the above-described energy system will be described as an example, but is not limited thereto. In addition, in the overlapping part mentioned above, the description is abbreviate | omitted.

An energy system operating method according to an embodiment of the present invention includes a first step of producing mechanical energy through a turbo machine (10); A second step of converting the produced mechanical energy into electrical energy; And a third step of controlling opening and closing of the first switch 50 and the second switch 60 through the control unit 70 to transfer the converted electric energy to the grid 30 or the energy storage unit 40. Include. According to the present invention, before the generator 20 and the grid 30 are connected, the low quality energy produced by the turbo machine 10 may be stored and utilized, thereby improving energy efficiency. Specifically, the present invention has the effect of storing and utilizing the energy generated in the state where the generator 20 and the grid 30 are not connected after the turbo machine 10 is started or stopped.

The first step is to produce mechanical energy through the turbo machine 10, where the turbo machine 10 may comprise a gas turbine or a steam turbine. The gas turbine is a power engine that mixes and burns compressed air and fuel compressed in the compressor 11, and rotates the turbine 13 with a high temperature gas generated by combustion. In general, the gas turbine is a compressor 11, a combustor. 12 and the turbine 13. The compressor 11 inhales and compresses the outside air to bring it into a state of high pressure and high temperature, and delivers it to the combustor 12. The combustor 12 mixes and combusts compressed air and fuel introduced from the compressor 11, and the combustion gas generated by the combustion is discharged to the turbine 13. The turbine 13 is rotated by the combustion gas, through which power is generated.

The second step is to convert the produced mechanical energy into electrical energy, where the mechanical energy produced by the turbo machine 10 is converted into electrical energy by a generator 20 connected to the turbo machine 10.

In a third step, controlling opening and closing of the first switch 50 and the second switch 60 through the control unit 70 to transfer the converted electric energy to the grid 30 or the energy storage unit 40. to be. That is, the generator 20 may send the converted electric energy to the grid 30 or the energy storage unit 40, and the grid 30 and the energy by the first switch 50 and the second switch 60, respectively. The storage unit 40 may be electrically connected or disconnected, and the controller 70 may store or utilize the energy produced by controlling the opening and closing of the first switch 50 and the second switch 60. In this case, the energy storage system (ESS) 40 stores electrical energy converted by the generator 20, and may use a battery, and the battery may be a secondary battery. The secondary battery is not particularly limited, and various known ones can be used, and the secondary battery is preferably at least one selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries, and lithium polymer batteries.

Specifically, in the third step, the control unit 70 controls to open the first switch 50 and close the second switch 60 below the preset power frequency (see FIG. 4). The first switch 50 is closed, the second switch 60 is controlled to be opened (see FIG. 5), which is produced in the acceleration phase of the turbo machine 10, but not connected to the grid 30. Therefore, energy of low quality that is not transmitted to the grid 30 may be stored in the energy storage unit 40. In addition, the energy produced after the turbo machine 10 is stopped and disconnected from the grid 30 may also be stored in the energy storage 40. The preset power frequency is specified for each country, and may be a value within a range of 50 to 60 Hz.

At this time, the controller 70 preferably determines whether the predetermined power frequency has been reached for a predetermined time. For example, when the preset power frequency is reached, the controller 70 determines whether the power frequency is changed for 10 seconds, and when the power frequency is synchronized with the preset power frequency for 10 seconds, closes the first switch. By controlling to open the second switch, the energy storage operation is interrupted.

Meanwhile, the third step may include changing electrical characteristics (AC / DC, voltage, frequency) before the converted electrical energy is transferred to the energy storage unit 40, which may be a PCS (Power Conditioning) such as a converter. System 80 is implemented.

Next, a computer-readable recording medium that records a program for executing an energy system operating method capable of storing unused power in a computer will be described. In the description, the above-described energy system will be described as an example, but is not limited thereto. In addition, in the overlapping part mentioned above, the description is abbreviate | omitted.

The computer-readable recording medium includes a program that can be executed in a general-purpose digital computer, and includes a magnetic storage medium (for example, a ROM, a floppy disk, a hard disk, etc.), an optical reading medium (for example, a CD-ROM, Storage media such as DVD, etc.).

The recording medium according to an embodiment of the present invention is a computer-readable recording medium that records a program for executing an energy system operating method capable of storing unused energy in a computer, and the energy system operating method includes a turbo machine ( A) producing mechanical energy through 10); Converting the produced mechanical energy into electrical energy; And controlling the opening and closing of the first switch 50 and the second switch 60 through the control unit 70 to transfer the converted electric energy to the grid 30 or the energy storage unit 40. do. According to the present invention, before the generator 20 and the grid 30 are connected, the low quality energy produced by the turbo machine 10 may be stored and utilized, thereby improving energy efficiency. Specifically, the present invention has the effect of storing and utilizing the energy generated in the state where the generator 20 and the grid 30 are not connected after the turbo machine 10 is started or stopped.

Step A is a step of producing mechanical energy through the turbo machine 10, where the turbo machine 10 may comprise a gas turbine or a steam turbine. The gas turbine is a power engine that mixes and burns compressed air and fuel compressed in the compressor 11, and rotates the turbine 13 with a high temperature gas generated by combustion. In general, the gas turbine is a compressor 11, a combustor. 12 and the turbine 13. The compressor 11 inhales and compresses the outside air to bring it into a state of high pressure and high temperature, and delivers it to the combustor 12. The combustor 12 mixes and combusts compressed air and fuel introduced from the compressor 11, and the combustion gas generated by the combustion is discharged to the turbine 13. The turbine 13 is rotated by the combustion gas, through which power is generated.

Step B is a step of converting the produced mechanical energy into electrical energy, wherein the mechanical energy produced by the turbo machine 10 is converted into electrical energy by a generator 20 connected to the turbo machine 10.

Step C is controlling opening and closing of the first switch 50 and the second switch 60 through the control unit 70 to transfer the converted electric energy to the grid 30 or the energy storage unit 40. . That is, the generator 20 may send the converted electric energy to the grid 30 or the energy storage unit 40, and the grid 30 and the energy by the first switch 50 and the second switch 60, respectively. The storage unit 40 may be electrically connected or disconnected, and the controller 70 may store or utilize the energy produced by controlling the opening and closing of the first switch 50 and the second switch 60. In this case, the energy storage system (ESS) 40 stores electrical energy converted by the generator 20, and may use a battery, and the battery may be a secondary battery. The secondary battery is not particularly limited, and various known ones can be used, and the secondary battery is preferably at least one selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries, and lithium polymer batteries.

Specifically, in step C, the controller 70 controls to open the first switch 50 and close the second switch 60 below the preset power frequency (see FIG. 4). The first switch 50 is closed, the second switch 60 is controlled to be opened (see FIG. 5), which is produced in the acceleration stage of the turbomachine 10, but is not connected to the grid 30. Energy of low quality that is not transmitted to the grid 30 may be stored in the energy storage unit 40. In addition, the energy produced after the turbo machine 10 is stopped and disconnected from the grid 30 may also be stored in the energy storage 40. The preset power frequency is specified for each country and may be a value within a range of 50 to 60 Hz.

At this time, the controller 70 preferably determines whether the predetermined power frequency has been reached for a predetermined time. For example, when the preset power frequency is reached, the controller 70 determines whether the power frequency is changed for 10 seconds, and when the power frequency is synchronized with the preset power frequency for 10 seconds, closes the first switch. By controlling to open the second switch, the energy storage operation is interrupted.

Meanwhile, step C may include changing electrical characteristics (AC / DC, voltage, frequency) before the converted electrical energy is transferred to the energy storage unit 40, which may be a power conditioning system such as a converter. 80).

In the present specification, only a few examples of various embodiments performed by the present inventors are described, but the technical idea of the present invention is not limited thereto, but may be variously modified and implemented by those skilled in the art.

10: turbo machine
11: compressor
12: combustor
13: turbine
20: generator
30: grid
40: energy storage
50: first switch
60: second switch
70: control unit
80: PCS

Claims (27)

A turbo machine that produces mechanical energy;
A generator positioned at the rear of the turbo machine and converting the mechanical energy produced by the turbo machine into electrical energy;
A grid connected to the generator;
An energy storage system connected to the generator;
A first switch for controlling a connection between the generator and the grid;
A second switch for regulating a connection between the generator and the energy storage unit; And
And a controller configured to control opening and closing of the first switch and the second switch.
The control unit opens the first switch below the preset power frequency, closes the second switch, stores the electrical energy converted from the generator in the energy storage unit, and changes the power frequency for 10 seconds when the preset power frequency is reached. If it is determined that the power frequency maintains the preset power frequency for 10 seconds, the first switch is closed, the second switch is opened, and the electrical energy converted from the generator is supplied to the grid.
The preset power frequency is a value in the range of 50 to 60 Hz,
Located in front of the energy storage unit, further comprising a PCS (Power Conditioning System) for changing the voltage or frequency, which is an electrical characteristic of the power received from the generator, the energy system capable of storing unused power. The turbo machine of claim 1, wherein
An energy system capable of storing unused power, characterized in that it comprises a gas turbine or a steam turbine. The method of claim 1, wherein the energy storage unit,
An energy system capable of storing unutilized power, characterized in that it is a battery. The battery of claim 3, wherein the battery is
An energy system capable of storing unused electric power, characterized in that it is a secondary battery. The method of claim 4, wherein the secondary battery,
At least one selected from the group consisting of nickel cadmium battery, nickel hydrogen battery, lead storage battery, lithium ion battery and lithium polymer battery, energy system capable of storing unused power. delete delete delete delete In the energy system operating method for operating the energy system according to any one of claims 1 to 5,
A first step of producing mechanical energy via a turbo machine;
A second step of converting the produced mechanical energy into electrical energy; And
And a third step of controlling opening and closing of the first switch and the second switch through the control unit to transfer the converted electric energy to the grid or the energy storage unit.
In the third step, the controller opens the first switch below the preset power frequency, closes the second switch, stores the electrical energy converted by the generator in the energy storage unit, and when the preset power frequency is reached, the power frequency for 10 seconds. If the power frequency maintains the preset power frequency for 10 seconds, the first switch is closed, the second switch is opened, and the electrical energy converted from the generator is supplied to the grid.
The preset power frequency is a value in the range of 50 to 60 Hz,
The third step may further include changing a voltage or frequency, which is an electrical characteristic, before transferring the converted electrical energy to the energy storage unit. The turbo machine of claim 10, wherein
Method for operating an energy system, characterized in that it comprises a gas turbine or steam turbine. The method of claim 10, wherein the energy storage of the third step,
An energy system operating method, characterized in that the battery. The method of claim 10, wherein the battery,
An energy system operating method, characterized in that the secondary battery. The method of claim 13, wherein the secondary battery,
And at least one selected from the group consisting of nickel cadmium batteries, nickel hydrogen batteries, lead storage batteries, lithium ion batteries and lithium polymer batteries. delete delete delete delete delete delete delete delete delete delete delete delete delete

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