Converter

Abstract

According to an embodiment, a converter is provided, the converter comprising: a transformer; a first full bridge circuit connected to a primary side of the transformer; a second full bridge circuit connected to a secondary side of the transformer; a first capacitor unit connected in parallel to the first full bridge circuit; a second capacitor unit connected in parallel to the second full bridge circuit; a first switching unit connected between the first full bridge circuit and the first capacitor unit; a second switching unit connected between the second full bridge circuit and the second capacitor unit; and a control unit for controlling operations of the first switching unit and the second switching unit so that a first voltage output from a power source is converted into a second voltage through the first full bridge circuit and the second full bridge circuit and supplied to a load.

Description

converter

[0001] The embodiment relates to a converter, and more specifically to a DC-DC converter.

[0002] To power electronic circuits or connect them to a power grid for use in applications, conversion to a specific voltage level is essential. In particular, applications requiring relatively high voltages necessitate stepping up the input voltage. Conversely, some electronic circuits require stepping down high voltages to lower levels. To achieve this voltage conversion, modeling and analysis of various step-up and step-down DC-DC converters are actively being studied.

[0003] Recently, active development is underway on bidirectional power converters, which combine a charging function that boosts the input voltage to charge the load and a discharging function that boosts the output voltage to regenerate it back to the input voltage. These bidirectional converters are playing a crucial role in various applications, including energy storage systems (ESS) and electric vehicles (EVs).

[0004] The CLLC resonant converter is a type of resonant converter frequently used for high-efficiency power conversion, and is particularly useful in applications where high efficiency and reduced electromagnetic interference (EMI) are important.

[0005] However, in the case of CLLC converters, there is a difficulty in securing a wide output voltage, and there is a disadvantage in that a wide range of operating frequencies must be used to secure a wide voltage range.

[0006] The technical problem to be achieved by the present invention is to provide a converter capable of providing various output voltages at a single frequency.

[0007] According to an embodiment, a converter is provided, comprising: a transformer; a first full bridge circuit connected to a primary side of the transformer; a second full bridge circuit connected to a secondary side of the transformer; a first capacitor unit connected in parallel to the first full bridge circuit; a second capacitor unit connected in parallel to the second full bridge circuit; a first switching unit connected between the first full bridge circuit and the first capacitor unit; a second switching unit connected between the second full bridge circuit and the second capacitor unit; and a control unit that controls operations of the first switching unit and the second switching unit such that a first voltage output from a power source is converted into a second voltage through the first full bridge circuit and the second full bridge circuit and supplied to a load.

[0008] The first full bridge circuit may include a first switching element and a second switching element of a first leg connected to one end of the primary side of the transformer, a third switching element and a fourth switching element of a second leg connected to the other end of the primary side of the transformer, and the second full bridge circuit may include a fifth switching element and a sixth switching element of a third leg connected to one end of the secondary side of the transformer, and a seventh switching element and an eighth switching element of a fourth leg connected to the other end of the secondary side of the transformer.

[0009] The first capacitor unit may include a first capacitor element and a second capacitor element arranged in series, and the second capacitor unit may include a third capacitor element and a fourth capacitor element arranged in series.

[0010] The control unit can operate in the first mode by controlling the first switching unit to turn on and controlling the second switching unit, the first switching element, and the second switching element to turn off.

[0011] A converter in which the second voltage in the first mode has a lower voltage than the first voltage.

[0012] The above control unit can operate in the second mode by controlling the first switching unit and the second switching unit to turn off.

[0013] In the second mode, the first voltage can be converted into the second voltage according to the turns ratio of the transformer.

[0014] The above control unit can operate in a third mode by controlling the first switching unit to turn off and the second switching unit to turn on.

[0015] In the third mode, the second voltage may have a higher voltage than the first voltage.

[0016] The above control unit can control the first switching unit, the first switching element, and the fourth switching element to be turned off, and control the second switching unit to be turned on, thereby operating in the fourth mode.

[0017] In the fourth mode, the first voltage can be converted into the second voltage according to the turns ratio of the transformer.

[0018] The converter according to the embodiment can provide various output voltages.

[0019] Additionally, a wide voltage range can be secured through multiple mode operation.

[0020] Additionally, a wide voltage range can be secured while minimizing frequency variation.

[0021] Additionally, it can extend the life of the power-side bridge circuit.

[0022] Figure 1 is a configuration diagram of a converter according to an embodiment.

[0023] Figure 2 is a circuit diagram of a converter according to an embodiment.

[0024] Figures 3 to 12 are drawings for explaining the operation of the converter according to the control of the control unit.

[0025] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0026] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0027] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which the present invention belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0028] Additionally, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0029] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0030] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used.

[0031] These terms are intended only to distinguish one component from another, and are not intended to limit the nature, order, or sequence of the component.

[0032] And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, it may include not only cases where the component is directly connected, coupled or connected to the other component, but also cases where the component is 'connected', 'coupled' or 'connected' by another component between the component and the other component.

[0033] Additionally, when described as being formed or arranged "above or below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below", it can include the meaning of a downward direction as well as an upward direction based on one component.

[0034] Hereinafter, embodiments will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or corresponding components are given the same reference numbers, and redundant descriptions thereof will be omitted.

[0035] Figure 1 is a configuration diagram of a converter according to an embodiment, and Figure 2 is a circuit diagram of a converter according to an embodiment.

[0036] Referring to FIGS. 1 and 2, a converter (100) according to an embodiment may include a transformer (130), a first full bridge circuit (110) connected to the primary side of the transformer (130), a second full bridge circuit (120) connected to the secondary side of the transformer (130), a first capacitor unit (140) connected in parallel to the first full bridge circuit (110), a second capacitor unit (150) connected in parallel to the second full bridge circuit (120), a first switching unit (160) connected between the first full bridge circuit (110) and the first capacitor unit (140), a second switching unit (170) connected between the second full bridge circuit (120) and the second capacitor unit (150), and a control unit (180).

[0037] A converter (100) according to an embodiment may be configured to receive a first voltage, which is a DC voltage, from a power source (Q100) and provide a second voltage, which is a DC voltage, to a load (Q121).

[0038] The first full bridge circuit (110) can provide an alternating current (AC) waveform, such as a high-frequency waveform, to the primary windings of the transformer (130). The first full bridge circuit (110) can include a first switching element (Q103) and a second switching element (Q104) of a first leg connected to one end of the primary side of the transformer (130), and a third switching element (Q105) and a fourth switching element (Q106) of a second leg connected to the other end of the primary side of the transformer (130). Each switching element can be composed of a MOSFET element.

[0039] The transformer (130) may include a resonant circuit including a magnetizing inductor (Q115), resonant inductors (Q113, Q114), and resonant capacitors (Q111, Q112). The resonant inductors (Q113, Q114) determine a resonant frequency and may perform a function of inducing a change in current. The resonant capacitors (Q111, Q112) are elements that set a resonant frequency and may induce a change in voltage in a resonant state. The magnetizing inductor (Q115) may store energy by magnetic induction and assist the operation of the resonant circuit. The second full bridge circuit (120) may provide a DC voltage at an output terminal. The second full bridge circuit (120) may be connected to a secondary winding of the transformer (130). The second full bridge circuit (120) may include a fifth switching element (Q107) and a sixth switching element (Q108) of the third leg connected to one end of the secondary side of the transformer (130), and a seventh switching element (Q109) and an eighth switching element (Q110) of the fourth leg connected to the other end of the secondary side of the transformer (130). Each switching element may be composed of a MOSFET element.

[0040] The first capacitor unit (140) may include a first capacitor element (Q101) and a second capacitor element (Q102) arranged in series. One end of the first capacitor element (Q101) may be connected to a cathode terminal of a power source (Q100), and the other end may be connected to a first switching unit (160). One end of the second capacitor element (Q102) may be connected to an anode terminal of the power source (Q100), and the other end may be connected to a first switching unit (160).

[0041] The second capacitor unit (150) may include a third capacitor element (Q119) and a fourth capacitor element (Q120) arranged in series. One end of the third capacitor element (Q119) may be connected to one end of a load (Q121), and the other end may be connected to the second switching unit (170). One end of the fourth capacitor element (Q120) may be connected to the other end of the load (Q121), and the other end may be connected to the second switching unit (170).

[0042] The first switching unit (160) may be connected between the first full bridge circuit (110) and the first capacitor unit (140). One end of the first switching unit (160) may be connected to a contact node of the first capacitor element (Q101) and the second capacitor element (Q102). The other end of the first switching unit (160) may be connected to a contact node of the first switching element (Q103) and the second switching element (Q104). The first switching unit (160) may be configured as an IC element.

[0043] The second switching unit (170) may be connected between the second full bridge circuit (120) and the second capacitor unit (150). One end of the second switching unit (170) may be connected to the contact nodes of the third capacitor element (Q119) and the fourth capacitor element (Q120). The other end of the second switching unit (170) may be connected to the contact nodes of the seventh switching element (Q109) and the eighth switching element (Q110). The second switching unit (170) may be configured as an IC element.

[0044] The converter (100) according to the embodiment can convert power using the resonance phenomenon. The switching elements of the first full bridge circuit (110) can be switched on and off at regular intervals under the control of the control unit (180) to generate an AC signal. The generated AC signal can be supplied to the resonance circuit.

[0045] In the resonant circuit of the transformer (130), the voltage and current resonate at a set resonant frequency through the resonant capacitors (Q111, Q112) and the resonant inductors (Q113, Q114). At this time, the waveform of the voltage or current increases significantly at a specific frequency, and this can be used to perform a desired voltage conversion. The resonant inductors (Q113, Q114) and the resonant capacitors (Q111, Q112) can contribute to controlling the voltage gain by adjusting the impedance of the resonant circuit.

[0046] The transformer (130) can convert the voltage applied to the primary side through the first full bridge circuit (110) according to the turns ratio and voltage gain and transmit it to the second full bridge circuit (120).

[0047] The voltage converted through the transformer (130) can be converted into a stable DC voltage through the second full bridge circuit (120). The converted DC voltage can ultimately be supplied to the load (Q121).

[0048] The converter (100) according to the embodiment can control the output voltage supplied to the load (Q121) through frequency adjustment. The control unit (180) can maintain a stable output by adjusting the resonant frequency when the load (Q121) conditions change.

[0049] The control unit (180) can control the operation of the first switching unit (160) and the second switching unit (170) so that the first voltage output from the power source (Q100) is converted into a second voltage through the first full bridge circuit (110) and the second full bridge circuit (120) and supplied to the load (Q121).

[0050] The control unit (180) can control the on / off operation of the first switching unit (160) and the second switching unit (170), and the first full bridge circuit (110) and the second full bridge circuit (120) to boost or lower the first voltage and transmit it to the load (Q121).

[0051] Figures 3 to 12 are drawings for explaining the operation of the converter according to the control of the control unit.

[0052] Referring to FIGS. 3 to 5 together, the control unit (180) can control the first switching unit (160) to be turned on, and the second switching unit (170), the first switching element (Q103), and the second switching element (Q104) to be turned off, thereby operating in the first mode. The control unit (180) can control the third switching element (Q105) to the eighth switching element (Q110) to be turned on and off, respectively, with a fixed duty ratio (50%).

[0053] As shown in FIG. 3, in the first mode state, when the fourth switching element (Q106), the fifth switching element (Q107), and the eighth switching element (Q110) are turned on and the third switching element (Q105), the sixth switching element (Q108), and the seventh switching element (Q109) are turned off, a current movement path composed of a power source (Q100), a first capacitor element (Q101), a first switching unit (160), a transformer (130), and a fourth switching element (Q106) can be formed on the primary side. In addition, a current movement path composed of a transformer (130), a fifth switching element (Q107), a load (Q121), and an eighth switching element can be formed on the secondary side.

[0054] In addition, as shown in FIG. 4, in the first mode state, when the fourth switching element (Q106), the fifth switching element (Q107), and the eighth switching element (Q110) are turned off and the third switching element (Q105), the sixth switching element (Q108), and the seventh switching element (Q109) are turned on and operate, a current movement path composed of a power source (Q100), a third switching element (Q105), a transformer (130), a first switching unit (160), and a second capacitor element (Q102) can be formed on the primary side. In addition, a current movement path composed of a transformer (130), a seventh switching element (Q109), a load (Q121), and a sixth switching element can be formed on the secondary side.

[0055] As shown in Fig. 5, in the first mode, the second voltage can have a lower voltage than the first voltage. In the first mode, the second voltage can operate to have a voltage value that is 50% of the first voltage. Through this, the voltage of the power source (Q100) can be stepped down and transmitted to the load (Q121). That is, it can be confirmed that in the first mode, the first voltage of 600 [V] is stepped down to the second voltage of 300 [V] and transmitted to the load.

[0056] Referring to FIGS. 6 and 7 together, the control unit (180) can control the operation of the full bridge circuit by controlling the switching elements of the first full bridge circuit (110) and the second full bridge circuit (120) to turn on and turn off with a fixed duty ratio (50%) in the second mode. In the second mode, the control unit (180) can control the first switching unit (160) and the second switching unit (170) to turn off. In the second mode, the first voltage can be converted into a second voltage according to the turns ratio of the transformer (130) and transmitted to the load (Q121).

[0057] As shown in FIG. 6, in the second mode, when the first switching element (Q103), the fourth switching element (Q106), the fifth switching element (Q107), and the eighth switching element (Q110) are turned on and the second switching element (Q104), the third switching element (Q105), the sixth switching element (Q108), and the seventh switching element (Q109) are turned off, a current movement path composed of a power source (Q100), the first switching element (Q103), a transformer (130), and the fourth switching element (Q106) can be formed on the primary side. A current movement path composed of a transformer (130), the fifth switching element (Q107), a load (Q121), and the eighth switching element can be formed on the secondary side.

[0058] In addition, in the second mode, when the first switching element (Q103), the fourth switching element (Q106), the fifth switching element (Q107), and the eighth switching element (Q110) are turned off and the second switching element (Q104), the third switching element (Q105), the sixth switching element (Q108), and the seventh switching element (Q109) are turned on, a current movement path composed of a power source (Q100), a third switching element (Q105), a transformer (130), and a second switching element (Q104) can be formed on the primary side. A current movement path composed of a transformer (130), a seventh switching element (Q109), a load (Q121), and a sixth switching element (Q108) can be formed on the secondary side.

[0059] As shown in Fig. 7, in the second mode, the first voltage can be converted into a second voltage according to the turns ratio of the transformer (130) and transmitted to the load (Q121). That is, when the turns ratio is 1:1, it can be confirmed that in the second mode, the first voltage of 600 [V] is transmitted to the load as the second voltage of 600 [V].

[0060] Referring to FIGS. 8 to 10 together, the control unit (180) can control the first switching unit (160) to be turned off and the second switching unit (170) to be turned on, thereby operating in the third mode. The control unit (180) can control the first switching element (Q103) to the eighth switching element (Q110) to be turned on and off, respectively, with a fixed duty ratio (50%).

[0061] In the third mode state as shown in FIG. 8, when the first switching element (Q103), the fourth switching element (Q106), the fifth switching element (Q107), and the eighth switching element (Q110) are turned on and the second switching element (Q104), the third switching element (Q105), the sixth switching element (Q108), and the seventh switching element (Q109) are turned off, a current movement path composed of a power source (Q100), the first switching element (Q103), a transformer (130), and the fourth switching element (Q106) can be formed on the primary side. A current movement path composed of a transformer (130), the fifth switching element (Q107), the third capacitor element (Q119), and the second switching unit (170) can be formed on the secondary side.

[0062] In addition, in the third mode, when the first switching element (Q103), the fourth switching element (Q106), the fifth switching element (Q107), and the eighth switching element (Q110) are turned off and the second switching element (Q104), the third switching element (Q105), the sixth switching element (Q108), and the seventh switching element (Q109) are turned on, a current movement path composed of a power source (Q100), a third switching element (Q105), a transformer (130), and a second switching element (Q104) can be formed on the primary side. A current movement path composed of a transformer (130), a second switching unit (170), a fourth capacitor element (Q120), and a sixth switching element (Q108) can be formed on the secondary side.

[0063] That is, when the voltage applied to the transformer (130) is a positive voltage, the third capacitor element (Q119) is charged, and when it is a negative voltage, the fourth capacitor element (Q120) is charged. Through this, as shown in Fig. 10, the second voltage value transmitted to the load (Q121) can be twice the number of transformer turns of the first voltage output from the power source (Q100). Therefore, in the third mode, the second voltage can have a voltage twice as high as the first voltage. That is, it can be confirmed that in the third mode, the first voltage of 600 [V] is boosted to the second voltage of 1200 [V] and transmitted to the load.

[0064] Referring to FIGS. 11 and 12 together, the control unit (180) can control the first switching unit (160), the first switching element (Q103), and the fourth switching element (Q106) to be turned off, and the second switching unit (170) to be turned on, thereby operating in the fourth mode. The control unit (180) can control the second switching element (Q104), the third switching element (Q105), the fifth switching element (Q107) to the eighth switching element (Q110) to perform a turning-on and turning-off operation with a fixed duty ratio (50%), respectively.

[0065] As shown in Fig. 11, in the fourth mode state, when the second switching element (Q104), the third switching element (Q105), the fifth switching element (Q107), and the eighth switching element (Q110) are turned on and the sixth switching element (Q108) and the seventh switching element (Q109) are turned off, a current movement path composed of a power source (Q100), a third switching element (Q105), a transformer (130), and a second switching element (Q104) can be formed on the primary side. A current movement path composed of a transformer (130), a fifth switching element (Q107), a third capacitor element (Q119), and a second switching unit (170) can be formed on the secondary side.

[0066] That is, the fourth mode may refer to a mode that operates only in the case of positive or negative voltage in the third mode. As shown in Fig. 12, in the fourth mode, since the primary side applies voltage to the transformer with a duty ratio of 50%, the stress on the primary side circuit may be reduced. In addition, the second voltage converted according to the turns ratio of the transformer (130) may be transmitted to the load (Q121). That is, when the turns ratio is 1:1, it can be confirmed that in the fourth mode, the first voltage of 600 [V] is transmitted to the load as the second voltage of 600 [V].

[0067] The term '~ part' used in this embodiment means a software or hardware component such as an FPGA (field-programmable gate array) or an ASIC, and the '~ part' performs certain roles. However, the '~ part' is not limited to software or hardware. The '~ part' may be configured to be on an addressable storage medium and may be configured to play one or more processors. Thus, as an example, the '~ part' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and '~ parts' may be combined into a smaller number of components and '~ parts' or further separated into additional components and '~ parts'. Additionally, components and '~parts' may be implemented to regenerate one or more CPUs within a device or secure multimedia card.

[0068] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

Claims

1. Transformers; A first full bridge circuit connected to the primary side of the above transformer; A second full bridge circuit connected to the secondary side of the above transformer; A first capacitor section connected in parallel to the first full bridge circuit; A second capacitor section connected in parallel to the second full bridge circuit; A first switching unit connected between the first full bridge circuit and the first capacitor unit; A second switching unit connected between the second full bridge circuit and the second capacitor unit; and A converter including a control unit that controls the operation of the first switching unit and the second switching unit so that the first voltage output from the power source is converted into a second voltage through the first full bridge circuit and the second full bridge circuit and supplied to the load.

2. In paragraph 1, The first full bridge circuit includes a first switching element and a second switching element of a first leg connected to one end of the primary side of the transformer, and a third switching element and a fourth switching element of a second leg connected to the other end of the primary side of the transformer. The second full bridge circuit is a converter including a fifth switching element and a sixth switching element of a third leg connected to one end of the secondary side of the transformer, and a seventh switching element and an eighth switching element of a fourth leg connected to the other end of the secondary side of the transformer.

3. In paragraph 2, The above first capacitor section includes a first capacitor element and a second capacitor element arranged in series, A converter in which the second capacitor section includes a third capacitor element and a fourth capacitor element arranged in series.

4. In paragraph 3, A converter in which the control unit controls the first switching unit to turn on and the second switching unit, the first switching element and the second switching element to turn off, thereby operating in the first mode.

5. In paragraph 4, A converter wherein in the first mode, the second voltage has a lower voltage than the first voltage.

6. In paragraph 3, The above control unit controls the first switching unit and the second switching unit to turn off and operate the converter in the second mode.

7. In paragraph 5, A converter in which, in the second mode, the first voltage is converted into the second voltage according to the turns ratio of the transformer.

8. In paragraph 3, A converter in which the above control unit controls the first switching unit to turn off and the second switching unit to turn on to operate in a third mode.

9. In paragraph 7, A converter in which the second voltage in the third mode has a higher voltage than the first voltage.

10. In paragraph 3, A converter in which the control unit controls the first switching unit, the first switching element, and the fourth switching element to turn off and the second switching unit to turn on, thereby operating in the fourth mode.

11. In paragraph 10, A converter in which, in the fourth mode, the first voltage is converted into the second voltage according to the turns ratio of the transformer.

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