SPWM control device of TAB converter for obtaining high efficiency in wide voltage range

The SPWM control device for TAB converters addresses inefficiencies and cooling needs by performing ZVS across a wide voltage range, reducing losses and cooling requirements, thereby improving efficiency and safety.

WO2025254275A1PCT designated stage Publication Date: 2025-12-11HYOSUNG HEAVY IND CORP
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Patent Information

Application Number
PCT/KR2024/019058
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-06-04
Filing Date
2024-11-27
Publication Date
2025-12-11

AI Technical Summary

Technical Problem

Existing DC-DC converters for renewable energy systems face inefficiencies due to voltage fluctuations and require excessive cooling equipment to manage switching losses, increasing costs and risking system damage.

Method used

An SPWM control device for a Triple-Active Bridge (TAB) converter that minimizes power transmission losses by performing Zero Voltage Switching (ZVS) across a wide voltage range, dividing the converter into a battery side and two output sides, and controlling it like a Dual-Active Bridge (DAB) to achieve high efficiency.

Benefits of technology

The solution reduces switching losses and minimizes the need for cooling equipment, enhancing efficiency and simplifying control across a wide voltage range while protecting the converter components.

✦ Generated by Eureka AI based on patent content.

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Abstract

The present invention relates to an SPWM control device of a TAB converter, which can increase efficiency by performing switching to minimize loss of power transmission between a battery and a load or converter when controlling the TAB converter, can perform control while obtaining ZVS simply and in a wide range compared to conventional TAB control by performing control like DAB, by dividing the TAB converter into a battery side and the remaining two output sides when controlling the TAB converter, and can minimize cooling equipment and obtain high efficiency in a wide voltage range by performing ZVS soft switching by a switch in the TAB converter even in the wide voltage range to minimize switching loss of the TAB converter. The SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range comprises a battery connected to a first port of the TAB converter to charge or discharge power, a load or converter including a load consuming power of the battery or a converter that supplies power to the battery by serially connecting a second port and a third port of the TAB, and a control unit that controls a switch inside the TAB.
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Description

SPWM control device of TAB converter for high efficiency over a wide voltage range

[0001] The present invention relates to a SPWM (Single PWM) control device of a TAB converter for obtaining high efficiency in a wide voltage range, and more particularly, to switching so as to minimize loss in power transmission between a battery and a load or a converter when controlling a TAB (Triple-Active Bridge) converter. In addition, the present invention relates to a SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, in which a switch within the TAB converter can perform ZVS (Zero Voltage Switching) soft switching even in a wide voltage range in order to minimize switching loss of the TAB converter.

[0002] The recent surge in fossil fuel use, coupled with climate change and global warming, has led to a growing demand for alternative energy sources. To address this, the development and adoption of distributed power sources and energy storage systems based on renewable energy sources like solar and wind power are actively underway.

[0003] A common requirement in these distributed power generation and energy storage systems is a DC-DC converter, which converts the energy generated from renewable energy sources and energy storage devices into a stable power source for end users. The DC-DC converters used here must be able to compensate for the significant fluctuations in input and output voltages and the irregularity of power output, both of which are inherent disadvantages of renewable energy sources. Furthermore, they must be unaffected by voltage fluctuations and exhibit high efficiency across a wide voltage range.

[0004] As an example, Korean Patent Publication No. 10-2022-0143450 discloses a system for removing backflow power of a three-port DC-DC converter by using a dual phase shift (DPS) control method in a TAB converter to reduce backflow power present in the TAB converter and increase overall system efficiency.

[0005] However, even in this case, when the input / output transformation ratio of the TAB converter is controlled to be 1:1, ZVS (Zero Voltage Switching) soft switching is possible in the entire range, but loss occurs if the transformation ratio is not 1:1.

[0006] Therefore, in order to be used in connection with applications with a wide voltage range, such as batteries, the transformer ratio is not 1:1, so excessive cooling equipment is required to take into account switching losses.

[0007] These excessive cooling systems have the disadvantage of increasing the cost of the system and causing problems that can lead to system damage if the cooling is done incorrectly.

[0008] The purpose of the present invention is to provide an SPWM control device for a TAB converter that can increase efficiency by switching so that loss in battery and load or converter power transmission is minimized when controlling a TAB (Triple-Active Bridge) converter, and to control the TAB like a DAB by dividing it into a battery side and the remaining two output sides, thereby obtaining ZVS in a wide range more simply than the existing TAB control and obtaining high efficiency in a wide voltage range that can be controlled.

[0009] Another purpose of the present invention is to provide an SPWM control device for a TAB converter that performs ZVS soft switching of a switch within a TAB converter even over a wide voltage range in order to minimize switching loss of the TAB converter, thereby minimizing cooling equipment and obtaining high efficiency over a wide voltage range.

[0010] An SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range according to the present invention may include a battery connected to a first port of a TAB (Triple-Active Bridge) converter to charge or discharge power, a load or converter configured to consume power from the battery or a converter supplying power to the battery by connecting the second and third ports of the TAB in series, and a control unit that controls a switch inside the TAB.

[0011] Here, the control unit can perform boost control when the voltage of the load or converter is higher than the voltage of the battery to satisfy the ZVS (Zero Voltage Switching) condition.

[0012] In addition, the step-up control can control the switching of the first port so that the '+' voltage and the '-' voltage have a duty of 0.5, but the switching of the second and third ports can be controlled so that the '+' voltage and the '-' voltage have a duty of 0.5 or less.

[0013] Here, a duty of 0.5 or less can add a '0' voltage between the '+' and '-' voltages.

[0014] In addition, the ZVS condition may be characterized by the fact that when the voltage of the first port rises from a '-' voltage to a '+' voltage, the current value flowing in the first port is '0' or less, when the voltages of the second and third ports rise from a '-' voltage to a '0' voltage, the current value flowing in the first port is '0' or more, and when the voltages of the second and third ports rise from a '0' voltage to a '+' voltage, the current value flowing in the first port is '0' or more.

[0015] Here, the control unit can perform step-down control when the voltage of the load or converter is lower than the voltage of the battery to satisfy the ZVS (Zero Voltage Switching) condition.

[0016] In addition, the forced control controls the switching of the second and third ports so that the '+' voltage and '-' voltage have a duty of 0.5, but the switching of the first port can be controlled so that the '+' voltage and '-' voltage have a duty of 0.5 or less.

[0017] Here, a duty of 0.5 or less can add a '0' voltage between the '+' and '-' voltages.

[0018] In addition, the ZVS condition may be characterized by the fact that when the voltage of the first port rises from a '0' voltage to a '+' voltage, the current value flowing in the first port is '0' or less, when the voltages of the second and third ports rise from a '-' voltage to a '+' voltage, the current value flowing in the first port is '0' or more, and when the voltage of the first port falls from a '+' voltage to a '0' voltage, the current value flowing in the first port is '0' or more.

[0019] The SPWM control device of the TAB converter for obtaining high efficiency in a wide voltage range according to the present invention can increase efficiency by switching so that the loss of battery and load or converter power transmission is minimized when controlling the TAB (Triple-Active Bridge) converter, and when controlling the TAB converter, it is divided into the battery side and the remaining two output sides and controlled like DAB, so that it has the advantage of being able to control while obtaining ZVS in a wide range while being simple compared to the existing TAB control.

[0020] In addition, the SPWM control device of the TAB converter for obtaining high efficiency in a wide voltage range according to the present invention has the advantage of minimizing the cooling equipment by performing ZVS soft switching of the switches within the TAB converter even in a wide voltage range to minimize the switching loss of the TAB converter.

[0021] FIG. 1 is a block diagram showing an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range according to one embodiment of the present invention, wherein FIG. 1(a) shows an example of charging power to a battery from a load or a converter, and FIG. 1(b) shows an example of supplying power from a battery to a load or a converter.

[0022] Figure 2 is a block diagram showing a case where the load or converter voltage of Figure 1 is boosted higher than the battery voltage.

[0023] Figure 3 is a signal waveform showing the detailed voltage and current of Figure 2.

[0024] Figure 4 is a signal waveform showing the signal waveform of Figure 3 in more detail.

[0025] Fig. 5 is a block diagram showing a case where the load or converter voltage of Fig. 1 is lower than the battery voltage and is forced.

[0026] Figure 6 is a signal waveform showing the detailed voltage and current of Figure 5.

[0027] Figure 7 is a signal waveform showing the signal waveform of Figure 6 in more detail.

[0028] Hereinafter, specific embodiments for carrying out the present invention will be described with reference to the attached drawings.

[0029] When describing the present invention, terms such as "first" and "second" may be used to describe various components. However, the components may not be limited by these terms. The terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, the first component could be referred to as the "second component," and similarly, the second component could also be referred to as the "first component."

[0030] When it is said that a component is connected or connected to another component, it can be understood that it may be directly connected or connected to that other component, but there may also be other components in between.

[0031] The terminology used in this specification is for the purpose of describing specific embodiments only and is not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly dictates otherwise.

[0032] In this specification, terms such as “include” or “have” are intended to indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and can be understood as not excluding in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0033] Additionally, the shape and size of elements in the drawing may be exaggerated for clearer explanation.

[0034] Hereinafter, with reference to the attached drawings, a detailed description will be given of an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range according to the present invention.

[0035] FIG. 1 is a block diagram showing an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range according to one embodiment of the present invention, wherein FIG. 1(a) is an example of charging power to a battery (100) from a load or a converter (200), and FIG. 1(b) is an example of supplying power from a battery (100) to a load or a converter (200), and FIGS. 2 to 7 are detailed block diagrams and signal waveforms for explaining FIG. 1 in detail.

[0036] Hereinafter, an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range according to one embodiment of the present invention will be described with reference to FIGS. 1 to 7.

[0037] First, referring to FIG. 1, an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range according to an embodiment of the present invention comprises a battery (100) connected to a first port (110) of a TAB (Triple-Active Bridge) converter to charge or discharge power, a load or converter (200) configured as a load that consumes power from the battery (100) or a converter that supplies power to the battery (100) by connecting the second port (220) and the third port (230) of the TAB in series, and a control unit (300) that controls a switch inside the TAB.

[0038] Here, the TAB converter can output the same power by connecting the second port (220) and the third port (230) in series and making the control command the same, so that it can be operated simply like a DAB (Dual-Active Bridge).

[0039] At this time, the case where the load or converter (200) voltage is higher than the battery (100) voltage and is boosted is described in detail in FIGS. 2 to 4, and the case where the load or converter (200) voltage is lower than the battery (100) voltage and is boosted is described in detail in FIGS. 5 to 7.

[0040]

[0041] Figure 2 is a block diagram showing a case where the load or converter (200) voltage of Figure 1 is boosted higher than the battery (100) voltage.

[0042] As can be seen in Fig. 2, the control unit (300) performs boost control when the voltage of the load or converter (200) is higher than the voltage of the battery (100) to satisfy the ZVS (Zero Voltage Switching) condition.

[0043] In addition, the step-up control controls the switching of the first port (110) so that the '+' voltage and '-' voltage have a duty (Duty1) of 0.5, but controls the switching of the second port (220) and the third port (230) so that the '+' voltage and '-' voltage have a duty (Duty2) of 0.5 or less.

[0044] Here, ZVS refers to a case where switching occurs when both ends of the switching element inside the TAB converter are subjected to '0' voltage. By satisfying the ZVS condition, there is an advantage in that it can protect the element against switching and maximize power efficiency.

[0045]

[0046] Figure 3 is a signal waveform showing the detailed voltage and current of Figure 2.

[0047] As can be seen in Figure 3, a duty of 0.5 or less adds a '0' voltage between the '+' and '-' voltages.

[0048] That is, the duty of the '+' voltage and the duty of the '-' voltage are equal to or less than 0.5, and the remainder is filled with the '0' voltage.

[0049] Therefore, by adding a '0' voltage, there is an advantage of increasing the margin for further satisfying the ZVS condition, which is explained in detail in Fig. 4.

[0050]

[0051] Figure 4 is a signal waveform showing the signal waveform of Figure 3 in more detail.

[0052] As can be seen in Fig. 4, the ZVS condition can be characterized by the fact that when the voltage of the first port (110) rises from a '-' voltage to a '+' voltage, the current value flowing in the first port (110) is '0' or less, when the voltages of the second port (220) and the third port (230) rise from a '-' voltage to a '0' voltage, the current value flowing in the first port (110) is '0' or more, and when the voltages of the second port (220) and the third port (230) rise from a '0' voltage to a '+' voltage, the current value flowing in the first port (110) is '0' or more.

[0053] To explain this in detail, the step-up voltage modulation technique inputs a fixed duty ratio of 0.5 to the primary side, and a variable duty ratio to the secondary side. In addition, the phase difference φ between the fundamental waves of the primary and secondary sides is input together, which actually creates a phase difference between the primary and secondary sides, and power is transmitted through this.

[0054] In this way, the most important thing in the method of transmitting power by controlling the duty ratio and phase difference is to minimize the conduction current and the loss at the switching moment, and the method for minimizing the loss of the step-up voltage modulation technique is as shown in mathematical equation 1.

[0055] [Mathematical Formula 1]

[0056] I1<0, I2>0, I3>0,

[0057] Here, I1: the current value flowing through the first port (110) when the voltage of the battery (100) rises from '-' voltage to '+' voltage,

[0058] I2: Current value flowing in the first port (110) when the voltage of the second port (220) and the third port (230) rises from '-' voltage to '0' voltage.

[0059] I3: Current value flowing in the first port (110) when the voltage of the second port (220) and the third port (230) rises from '0' voltage to '+' voltage.

[0060] In addition, at the point where θ=θ0 and θ=θ2, there is a dead time period in which all switches on the primary side are turned off. At this time, the voltage stored in the parasitic capacitance on the primary side changes to '0' due to the current flowing in the inductor, thereby enabling ZVS turn-on switching.

[0061] Meanwhile, at the point where θ=θ1 and θ=θ3, there is a dead time period in which all switches on the secondary side are turned off. At this time, since current was flowing through the diode of the switch due to free current, there is no voltage stored in the capacitor, and therefore ZVS turn-on switching becomes possible.

[0062] Therefore, the SPWM control device of the TAB converter for obtaining high efficiency in a wide voltage range according to the present invention increases efficiency by switching so that the loss of power transmission between the battery (100) and the load or converter (200) is minimized when controlling the TAB converter, and when controlling the TAB converter, it is divided into the battery side and the remaining two output sides and controlled like DAB, so that control is possible while obtaining ZVS in a wide range while being simple compared to the existing TAB control, and the switch in the TAB converter performs ZVS soft switching even in a wide voltage range, thereby minimizing cooling equipment and having the advantage.

[0063]

[0064] Fig. 5 is a block diagram showing a case where the load or converter (200) voltage of Fig. 1 is lower than the battery (100) voltage and is forced.

[0065] As can be seen in Fig. 5, the control unit (300) performs step-down control when the voltage of the load or converter (200) is lower than the voltage of the battery (100) to satisfy the ZVS (Zero Voltage Switching) condition.

[0066] In addition, the forced control controls the switching of the second port (220) and the third port (230) so that the '+' voltage and the '-' voltage have a duty (Duty2) of 0.5, but controls the switching of the first port (110) so that the '+' voltage and the '-' voltage have a duty (Duty1) of 0.5 or less.

[0067] Here, ZVS refers to a case where switching occurs when both ends of the switching element inside the TAB converter are subjected to '0' voltage. By satisfying the ZVS condition, there is an advantage in that it can protect the element against switching and maximize power efficiency.

[0068]

[0069] Figure 6 is a signal waveform showing the detailed voltage and current of Figure 5.

[0070] As can be seen in Fig. 6, a duty of 0.5 or less adds a '0' voltage between the '+' and '-' voltages.

[0071] That is, the duty of the '+' voltage and the duty of the '-' voltage are equal to or less than 0.5, and the remainder is filled with the '0' voltage.

[0072] Therefore, by adding a '0' voltage, there is an advantage of increasing the margin for further satisfying the ZVS condition, which is explained in detail in Fig. 7.

[0073]

[0074] Figure 7 is a signal waveform showing the signal waveform of Figure 6 in more detail.

[0075] As can be seen in Fig. 7, the ZVS condition can be characterized by the fact that when the voltage of the first port (110) rises from a '0' voltage to a '+' voltage, the current value flowing in the first port (110) is '0' or less, when the voltages of the second port (220) and the third port (230) rise from a '-' voltage to a '+' voltage, the current value flowing in the first port (110) is '0' or more, and when the voltage of the first port (110) falls from a '+' voltage to a '0' voltage, the current value flowing in the first port (110) is '0' or more.

[0076] To explain this in detail, the step-down voltage modulation technique inputs a fixed duty ratio of 0.5 to the secondary side, and a variable duty ratio to the primary side. In addition, the phase difference φ between the fundamental waves of the primary and secondary sides is input together, which actually creates a phase difference between the primary and secondary sides, and power is transmitted through this.

[0077] In this way, the most important thing in the method of transmitting power by controlling the duty ratio and phase difference is to minimize the conduction current and the loss at the switching moment, and the method that can minimize the loss of the voltage modulation technique is as shown in mathematical equation 2.

[0078] [Equation 2]

[0079] I1<0, I2>0, I3>0,

[0080] Here, I1: the current value flowing in the first port (110) when the voltage of the first port (110) rises from '0' voltage to '+' voltage,

[0081] I2: Current value flowing in the first port (110) when the voltage of the second port (220) and the third port (230) rises from '-' voltage to '+' voltage.

[0082] I3: Current value flowing in the first port (110) when the voltage of the first port (110) drops from '+' voltage to '0' voltage.

[0083] In addition, at the point where θ=θ0 and θ=θ2, there is a dead time period in which all switches on the secondary side are turned off. At this time, the voltage stored in the parasitic capacitance on the secondary side changes to '0' due to the current flowing in the inductor, thereby enabling ZVS turn-on switching.

[0084] Meanwhile, at the point where θ=θ1 and θ=θ3, all switches on the primary side are turned off, but since current has already been flowing through the parallel diodes before, ZVS turn-on switching becomes possible.

[0085]

[0086] As described above, the SPWM control device of the TAB converter for obtaining high efficiency in a wide voltage range according to the present invention can increase efficiency by switching so that the loss of the battery and load or converter power transmission is minimized when controlling the TAB converter, and when controlling the TAB converter, it is divided into the battery side and the remaining two output sides and controlled like DAB, so that it has the advantage of being able to control while obtaining ZVS in a wide range while being simple compared to the existing TAB control, and in order to minimize the switching loss of the TAB converter, the switch in the TAB converter performs ZVS soft switching even in a wide voltage range, thereby minimizing the cooling equipment and having the advantage.

[0087]

[0088] Those skilled in the art will appreciate that the various illustrative logical blocks, modules, processors, means, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, various forms of programs or design code (referred to herein, for convenience, as software), or a combination of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

[0089] The various embodiments presented herein can be implemented as a method, apparatus, or article of manufacture using standard programming and / or engineering techniques. The term article of manufacture includes a computer program, carrier, or media accessible from any computer-readable storage device. For example, computer-readable storage media include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic strips, etc.), optical disks (e.g., CDs, DVDs, etc.), smart cards, and flash memory devices (e.g., EEPROMs, cards, sticks, key drives, etc.). Furthermore, various storage media presented herein include one or more devices and / or other machine-readable media for storing information.

[0090] It should be understood that the specific order or hierarchy of steps in the presented processes is merely an example of exemplary approaches. It should be understood that the specific order or hierarchy of steps in the processes may be rearranged within the scope of the present invention based on design priorities. The appended method claims provide elements of various steps in a sample order, but are not intended to be limited to the specific order or hierarchy presented.

[0091] The description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments disclosed herein, but is to be construed in the broadest scope consistent with the principles and novel features disclosed herein.

[0092] The present invention relates to a SPWM (Single PWM) control device of a TAB converter for obtaining high efficiency over a wide voltage range, and can be used in the converter field.

Claims

1. A battery that charges or discharges power by connecting to the first port of the TAB (Triple-Active Bridge) converter; A load or converter consisting of a load that consumes power from the battery or a converter that supplies power to the battery by connecting the second and third ports of the TAB in series; and An SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, including a control unit that controls a switch inside the TAB.

2. In paragraph 1, An SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized in that the control unit performs boost control when the voltage of the load or converter is higher than the voltage of the battery to satisfy the ZVS (Zero Voltage Switching) condition.

3. In paragraph 2, The above step-up control is an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized in that the switching of the first port is controlled so that the '+' voltage and the '-' voltage have a duty of 0.5, and the switching of the second port and the third port is controlled so that the '+' voltage and the '-' voltage have a duty of 0.5 or less.

4. In paragraph 3, The above-mentioned duty of 0.5 or less is an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized by adding a '0' voltage between the '+' voltage and the '-' voltage.

5. In paragraph 4, The ZVS condition is, When the voltage of the first port increases from '-' voltage to '+' voltage, the current value flowing through the first port is '0' or less, When the voltage of the second port and the third port rises from '-' voltage to '0' voltage, the current value flowing through the first port is '0' or more, An SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized in that the current value flowing through the first port is '0' or higher when the voltage of the second port and the third port rises from '0' voltage to '+' voltage.

6. In paragraph 1, An SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized in that the control unit performs step-down control when the voltage of the load or converter is lower than the voltage of the battery to satisfy the ZVS (Zero Voltage Switching) condition.

7. In paragraph 6, The above-mentioned forced control is a SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized in that the switching of the second port and the third port is controlled so that the '+' voltage and the '-' voltage have a duty of 0.5, and the switching of the first port is controlled so that the '+' voltage and the '-' voltage have a duty of 0.5 or less.

8. In paragraph 7, The above-mentioned duty of 0.5 or less is an SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized by adding a '0' voltage between the '+' voltage and the '-' voltage.

9. In paragraph 8, The ZVS condition is, When the voltage of the first port increases from '0' voltage to '+' voltage, the current value flowing through the first port is '0' or less, When the voltage of the second port and the third port rises from '-' voltage to '+' voltage, the current value flowing through the first port is '0' or more, An SPWM control device of a TAB converter for obtaining high efficiency in a wide voltage range, characterized in that the current value flowing through the first port is '0' or higher when the voltage of the first port drops from '+' voltage to '0' voltage.

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