Resonant converter and electric vehicle charger comprising same

Abstract

Provided are a resonant converter and an electric vehicle charger comprising same. The resonant converter comprises: a first input side circuit including a first primary winding; a second input side circuit including a second primary winding; a first switch configured to connect the first primary winding and the second primary winding; a first output side circuit including a first secondary winding and a first rectification network; a second output side circuit including a second secondary winding and a second rectification network; a second switch configured to connect the first secondary winding and the second secondary winding; and an output capacitor connected in parallel with the first output side circuit and the second output side circuit.

Description

Resonant converter and electric vehicle charger including the same

[0001] The present disclosure relates to a resonant converter and an electric vehicle charger including the same.

[0002] Electric vehicles (EVs) are vehicles powered by electric energy. Compared to conventional internal combustion engines, they emit significantly less carbon, making them a crucial application for addressing issues like environmental pollution and climate change. However, many challenges remain before EVs can become widespread, the most pressing of which is securing charging infrastructure.

[0003] Conventional electric vehicles are equipped with 400V batteries and operate with a voltage fluctuation range of approximately 150V to 500V. However, recently, the use of 800V batteries is increasing to meet the requirements of large-capacity charging and to reduce the weight of internal vehicle structures (e.g., bus bars). 800V batteries operate with a voltage fluctuation range of approximately 300V to 1,000V. Accordingly, a power conversion circuit for electric vehicle charging that can provide charging power with high efficiency over a wide voltage range of approximately 150V to 1,000V may be required.

[0004] Various embodiments seek to provide a resonant converter with a wide range of output voltages and an electric vehicle charger including the same. The technical challenges to be addressed by the present disclosure are not limited to the technical challenges described above, and other technical challenges can be inferred from the following embodiments.

[0005] As a means for solving the above-described technical problem, a resonant converter for an electric vehicle charger according to one aspect comprises: a first input circuit including a first switching bridge, a first resonant tank, and a first primary winding; a second input circuit connected in parallel with the first input circuit and including a second switching bridge, a second resonant tank, and a second primary winding; a first switch configured to electrically connect the first primary winding and the second primary winding in series; a first output circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first rectifier network; a second output circuit connected in parallel with the first output circuit and including a second secondary winding forming a second transformer together with the second primary winding, and a second rectifier network; a second switch configured to electrically connect the first secondary winding and the second secondary winding in series; And it may include an output capacitor connected in parallel with the first output side circuit and the second output side circuit.

[0006] According to another aspect, a resonant converter for an electric vehicle charger may include a first input circuit including a first switching bridge, a first resonant tank, and a first primary winding; a second input circuit connected in parallel with the first input circuit and including a second switching bridge, a second resonant tank, and a second primary winding; a switch configured to electrically connect the first primary winding and the second primary winding in series; a first output circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first rectifier network; a second output circuit connected in parallel with the first output circuit and including a second secondary winding forming a second transformer together with the second primary winding, and a second rectifier network; and an output capacitor connected in parallel with the first output circuit and the second output circuit.

[0007] According to another aspect, an electric vehicle charger comprises: an AC-DC converter for converting AC power received from an external power source into DC power; an electric reservoir for storing DC power received from the AC-DC converter; a DC-DC converter for converting DC power received from the AC-DC converter or the electric reservoir into DC power having a different voltage; and a control unit for controlling the AC-DC converter, the electric reservoir and the DC-DC converter, wherein the DC-DC converter comprises: a first input-side circuit including a first switching bridge, a first resonant tank and a first primary winding; a second input-side circuit connected in parallel with the first input-side circuit and including a second switching bridge, a second resonant tank and a second primary winding; a first switch configured to electrically connect the first primary winding and the second primary winding in series; a first secondary winding forming a first transformer together with the first primary winding, and a first output-side circuit including a first rectifier network; A second output-side circuit including a second secondary winding connected in parallel with the first output-side circuit and forming a second transformer together with the second primary winding, and a second rectifier network; a second switch connecting the first secondary winding and the second secondary winding; and an output capacitor connected in parallel with the first output-side circuit and the second output-side circuit.

[0008] A resonant converter and an electric vehicle charger including the same according to various embodiments of the present disclosure can provide a wide range of output voltages.

[0009] In addition, the resonant converter and the electric vehicle charger including the same according to various embodiments of the present disclosure can provide output voltages in various ranges depending on the open / close states of the first and second switches by arranging the first switch between the primary windings of the input-side circuits and arranging the second switch between the secondary windings of the output-side circuits.

[0010] In addition, the resonant converter and the electric vehicle charger including the same according to various embodiments of the present disclosure can provide output voltages in various ranges depending on the open / closed state of the switch by arranging a switch between the primary windings of the input-side circuits.

[0011] The effects of the embodiments are not limited to the effects described above, and effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the embodiments belong from this specification and the attached drawings.

[0012] Figures 1 to 6 are circuit diagrams illustrating resonant converters according to embodiments.

[0013] Figure 7 is a block diagram of an electric vehicle charger according to one embodiment.

[0014] A resonant converter for an electric vehicle charger according to one embodiment comprises: a first input circuit including a first switching bridge, a first resonant tank, and a first primary winding; a second input circuit connected in parallel with the first input circuit and including a second switching bridge, a second resonant tank, and a second primary winding; a first switch configured to electrically connect the first primary winding and the second primary winding in series; a first output circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first commutation network; a second output circuit connected in parallel with the first output circuit and including a second secondary winding forming a second transformer together with the second primary winding, and a second commutation network; a second switch configured to electrically connect the first secondary winding and the second secondary winding in series; And it may include an output capacitor connected in parallel with the first output side circuit and the second output side circuit.

[0015] When the first switch is opened and the second switch is opened, a first voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, and when the first switch is closed and the second switch is opened, a second voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, and the magnitude of the second voltage may be smaller than the magnitude of the first voltage.

[0016] When the first switch is opened and the second switch is closed, a third voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, and the magnitude of the third voltage may be greater than the magnitude of the first voltage.

[0017] When the first switch is closed and the second switch is closed, a fourth voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, and the magnitude of the fourth voltage may be greater than the magnitude of the second voltage and less than the magnitude of the third voltage.

[0018] The first input side circuit may be a first H-bridge circuit in which the first resonant tank and the first primary winding are arranged on the center line, and the second input side circuit may be a second H-bridge circuit in which the second resonant tank and the second primary winding are arranged on the center line.

[0019] The first switch may be configured to connect the center line of the first H-bridge circuit and the center line of the second H-bridge circuit.

[0020] The first switching bridge may include four bridge switches each disposed in the bridges of the first H-bridge circuit, and the second switching bridge may include four bridge switches each disposed in the bridges of the second H-bridge circuit.

[0021] The resonant converter may be configured such that when the first switch is closed, two bridge switches arranged on the first switch side among the four bridge switches of the first switching bridge and two bridge switches arranged on the first switch side among the four bridge switches of the second switching bridge are opened.

[0022] The first resonant tank and the first primary winding may be electrically connected in series, and the second resonant tank and the second primary winding may be electrically connected in series.

[0023] According to another embodiment, a resonant converter for an electric vehicle charger may include a first input circuit including a first switching bridge, a first resonant tank, and a first primary winding; a second input circuit connected in parallel with the first input circuit and including a second switching bridge, a second resonant tank, and a second primary winding; a switch configured to electrically connect the first primary winding and the second primary winding in series; a first output circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first rectifier network; a second output circuit connected in parallel with the first output circuit and including a second secondary winding forming a second transformer together with the second primary winding, and a second rectifier network; and an output capacitor connected in parallel with the first output circuit and the second output circuit.

[0024] When the switch is opened, a fifth voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, and when the switch is closed, a sixth voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, and the magnitude of the sixth voltage may be smaller than the magnitude of the fifth voltage.

[0025] The first input side circuit may be a first H-bridge circuit in which the first resonant tank and the first primary winding are arranged on the center line, and the second input side circuit may be a second H-bridge circuit in which the second resonant tank and the second primary winding are arranged on the center line.

[0026] The switch may be configured to connect the center line of the first H-bridge circuit and the center line of the second H-bridge circuit.

[0027] The first switching bridge may include four bridge switches each disposed in the bridges of the first H-bridge circuit, and the second switching bridge may include four bridge switches each disposed in the bridges of the second H-bridge circuit.

[0028] When the first switch is closed, two bridge switches arranged on the switch side among the four bridge switches of the first switching bridge and two bridge switches arranged on the switch side among the four bridge switches of the second switching bridge may be configured to open.

[0029] According to another embodiment, an electric vehicle charger comprises: an AC-DC converter for converting AC power received from an external power source into DC power; an electric reservoir for storing DC power received from the AC-DC converter; a DC-DC converter for converting DC power received from the AC-DC converter or the electric reservoir into DC power having a different voltage; and a control unit for controlling the AC-DC converter, the electric reservoir, and the DC-DC converter, wherein the DC-DC converter comprises: a first input-side circuit including a first switching bridge, a first resonant tank, and a first primary winding; a second input-side circuit connected in parallel with the first input-side circuit and including a second switching bridge, a second resonant tank, and a second primary winding; a first switch configured to electrically connect the first primary winding and the second primary winding in series; a first secondary winding forming a first transformer together with the first primary winding, and a first output-side circuit including a first rectifier network; A second output-side circuit including a second secondary winding connected in parallel with the first output-side circuit and forming a second transformer together with the second primary winding, and a second rectifier network; a second switch connecting the first secondary winding and the second secondary winding; and an output capacitor connected in parallel with the first output-side circuit and the second output-side circuit.

[0030] When the first switch is opened and the second switch is opened, a first voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, and when the first switch is closed and the second switch is opened, a second voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, and the magnitude of the second voltage may be smaller than the magnitude of the first voltage.

[0031] When the first switch is opened and the second switch is closed, a third voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, and the magnitude of the third voltage may be greater than the magnitude of the first voltage.

[0032] When the first switch is closed and the second switch is closed, a fourth voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, and the magnitude of the fourth voltage may be greater than the magnitude of the second voltage and less than the magnitude of the third voltage.

[0033] The terms used in the examples have been selected from widely used, current terms, taking into account the functions of the present invention. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, in which case their meanings will be described in detail in the relevant description of the invention. Therefore, the terms used in the present invention should be defined based on their meaning and the overall content of the present invention, rather than simply their names.

[0034] When a part of the specification is said to "include" a component, this does not exclude other components, but rather implies the inclusion of other components, unless otherwise specifically stated. Furthermore, terms such as "-unit" and "-module" used in the specification refer to a unit that processes at least one function or operation, which may be implemented in hardware, software, or a combination of hardware and software.

[0035] As used herein, when an expression such as "at least one" precedes an array of elements, it modifies the entire array of elements, not just each individual element. For example, the expression "at least one of a, b, and c" should be interpreted to include a, b, c, or a and b, a and c, b and c, or a and b and c.

[0036] Below, with reference to the attached drawings, embodiments of the present disclosure are described in detail so that those skilled in the art can easily implement them. The present disclosure may be implemented in a form that can be implemented in the various embodiments of the aerosol generating devices described above, or may be implemented in various different forms and is not limited to the embodiments described herein.

[0037] Fig. 1 is a circuit diagram illustrating a resonant converter according to one embodiment. Fig. 1 shows a first switch (Q P ) and the second switch (Q A ) represents a resonant converter when the open circuit is opened.

[0038] FIG. 1 illustrates a resonant converter (10) for an electric vehicle charger. The resonant converter (10) may refer to a device that converts power using a resonant circuit. The resonant converter (10) may be a DC-DC converter that converts input DC power into DC power having a different voltage and outputs it. The resonant converter (10) may be employed in an electric vehicle charger, and more specifically, may be arranged inside a power module for an electric vehicle charger. In addition to the resonant converter (10), the power module may further include a controller for controlling the resonant converter (10), a cooler for cooling the resonant converter (10), a socket portion including terminals for electrically connecting an external device to the resonant converter (10), and at least one of other types of converters.

[0039] The resonant converter (10) comprises a first switching bridge, a first resonant tank, and a first primary winding (N PA ) may include a first input side circuit including a first switching bridge. In one embodiment, the first switching bridge comprises a plurality of bridge switches (Q) controlled by at least one switching signal. 1A , Q 2A , Q 3A and Q 4A ) may be included. The first switching bridge may include a DC input voltage (V IN ) can generate a square wave output. The square wave output is generated by the first resonant tank and the first primary winding (N PA ) can be transmitted.

[0040] The first resonant tank is coupled to the first switching bridge and has a resonant inductor (L) connected in series. RA ) and resonant capacitor (C RA ) may be included. However, it is not necessarily limited thereto, and the first resonant tank may include a combination of at least one resonant inductor and at least one resonant capacitor connected in series or parallel.

[0041] The resonant converter (10) is connected in parallel with the first input side circuit, and includes a second switching bridge, a second resonant tank, and a second primary winding (N PB ) may include a second input side circuit including a second switching bridge. In one embodiment, the second switching bridge comprises a plurality of bridge switches (Q) controlled by at least one switching signal. 1B , Q 2B , Q 3B and Q 4B ) may be included. The second switching bridge may include a DC input voltage (V IN ) can generate a square wave output. The square wave output is generated by the second resonant tank and the second primary winding (N PB ) can be transmitted.

[0042] The second resonant tank is coupled to the second switching bridge and has a resonant inductor (L) connected in series. RB ) and resonant capacitor (C RB ) may be included. However, it is not necessarily limited thereto, and the second resonant tank may include a combination of at least one resonant inductor and at least one resonant capacitor connected in series or parallel.

[0043] Meanwhile, although Fig. 1 illustrates the first switching bridge and the second switching bridge as a full bridge configuration each including four bridge switches, this is not necessarily limited thereto. At least one of the first switching bridge and the second switching bridge may be a half bridge configuration including two bridge switches. In addition, at least one of the first switching bridge and the second switching bridge may be a full bridge configuration, but may operate in the same manner as a half bridge through control using a switching signal.

[0044] The resonant converter (10) has a first primary winding (N PA ) with the first transformer (T A ) constitutes the first secondary winding (N SA ), and a first output side circuit including a first rectifier network. A first transformer (T A ) is the first primary winding (N PA ) and first secondary winding (N SA ) can change the strength of the AC voltage in proportion to the turns ratio between the first input circuit and the first output circuit. The first resonant tank can form a first power conversion circuit. The first resonant tank can be a resonant inductor (L RA ) and resonant capacitor (C RA ) and includes a first transformer (T A ) has a magnetizing inductance, the first power conversion circuit may correspond to an LLC converter. The first rectifier network includes a plurality of bridge diodes (D) for converting AC input to DC output. R1A, D R2A , D R3A and D R4A ) may be included.

[0045] The resonant converter (10) is connected in parallel with the first output side circuit and the second primary winding (N PB ) with the second transformer (T B ) forming the second secondary winding (N SB ), and a second output side circuit including a second rectifier network. A second transformer (T B ) is the second primary winding (N PB ) and the second secondary winding (N SB ) can change the strength of the AC voltage in proportion to the turns ratio between the input and output circuits. The second input circuit and the second output circuit can form a second power conversion circuit. The second resonant tank may include a resonant inductor (L RB ) and resonant capacitor (C RB ) and a second transformer (T B ) has a magnetizing inductance, the second power conversion circuit may correspond to an LLC converter. The second rectifier network includes a plurality of bridge diodes (D) for converting AC input to DC output. R1B , D R2B , D R3B and D R4B ) may be included.

[0046] The resonant converter (10) has a first primary winding (N PA ) and the second primary winding (N PB ) electrically connected in series with the first switch (Q) P ) may be included. In addition, the resonant converter (10) may include a first secondary winding (N SA ) and the second secondary winding (N SB ) electrically connected in series with a second switch (Q) A ) may be included. In addition, the resonant converter (10) may include a first switch (Q P ) and the second switch (Q A) may further include a control circuit for determining whether to open or close.

[0047] 1st switch (Q P ) and the second switch (Q A ) each may include at least one of a metal-oxide-semiconductor field-effect transistor (MOSFET), a bipolar junction transistor (BJT), a gate turn-off thyristor (GTO), an integrated gate commutated thyristor (IGCT), an isolated gate bipolar transistor (IGBT), and a relay. However, the present invention is not limited thereto, and the first switch (Q P ) and the second switch (Q A ) may be another type of switch, including a two-way switch.

[0048] The resonant converter (10) has an output capacitor (C) shared by the first output side circuit and the second output side circuit. O ) may be included. The first switch (Q P ) and the second switch (Q A ) depending on whether the output capacitor (C) is open or closed. O ) may vary in the range of output voltage applied.

[0049] As shown in Fig. 1, the first switch (Q P ) and the second switch (Q A ) is open, the first input-side circuit and the second input-side circuit can operate in parallel, the first output-side circuit and the second output-side circuit can operate in parallel, and the first power conversion circuit and the second power conversion circuit can operate in parallel. Accordingly, the output capacitor (C O) can be applied with a first voltage based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit.

[0050] In one embodiment, the first power conversion circuit and the second power conversion circuit may operate in an interleaved manner to reduce current ripple. However, this is not necessarily limited. The first power conversion circuit and the second power conversion circuit may also operate in synchronization with the same timing by the same switching signals.

[0051] Fig. 2 is a circuit diagram illustrating a resonant converter according to one embodiment. Fig. 2 shows a first switch (Q P ) is closed and the second switch (Q A ) represents a resonant converter when the open circuit is opened.

[0052] Referring to Figure 2, the first input side circuit includes a first resonant tank and a first primary winding (N PA ) may include a first H-bridge circuit (H1) arranged on the center line. In addition, the second input side circuit may include a second resonant tank and a second primary winding (N PB ) may include a second H-bridge circuit (H2) arranged on the center line.

[0053] Bridge switches of the first switching bridge (Q 1A , Q 2A , Q 3A and Q 4A ) can be placed in the four bridges of the first H-bridge circuit (H1). In addition, the bridge switches (Q) of the second switching bridge 1B , Q 2B , Q 3B and Q 4B ) can be placed on the four bridges of the second H-bridge circuit (H2). The first switch (Q P ) can be arranged to connect the center lines of the first H-bridge circuit (H1) and the second H-bridge circuit (H2).

[0054] The resonant converter (10) has a first switch (Q P ) may further include a switching controller configured to control the first and second switching bridges depending on the open / closed state of the first and second switching bridges.

[0055] 1st switch (Q P ) is open, the switching controller operates the first switch (Q P ) Bridge switches (Q) placed close to 3A , Q 4A , Q 1B and Q 2B ) can be controlled to remain in an open state. In addition, the switching controller can control the first switch (Q P ) Bridge switches placed far apart (Q 1A , Q 2A , Q 3B and Q 4B ) is the DC input voltage (V IN ) can be controlled to generate a square wave output from the bridge switches (Q 1A , Q 2A , Q 3B and Q 4B ) is a square wave output generated by the first resonant tank, the first primary winding (N PA ), second resonant tank and second primary winding (N PB ) can be transmitted.

[0056] 1st switch (Q P ) is closed, the switching controller switches the bridge switches (Q) of the first switching bridge 1A , Q 2A , Q 3A and Q 4A ) is the DC input voltage (V IN ) can be controlled to generate a square wave output from the bridge switches (Q 1A , Q 2A , Q 3A and Q 4A ) is generated by the first resonant tank and the first primary winding (N PA) can be transmitted. In addition, the switching controller can be transmitted to the bridge switches (Q) of the second switching bridge. 1B , Q 2B , Q 3B and Q 4B ) is the DC input voltage (V IN ) can be controlled to generate a separate square wave output from the bridge switches (Q 1B , Q 2B , Q 3B and Q 4B ) is generated by the second resonant tank and the second primary winding (N PB ) can be transmitted.

[0057] As shown in Fig. 2, the first switch (Q P ) is closed and the second switch (Q A ) is open, the output capacitor (C O ) can be applied with a second voltage based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit. In addition, the first switch (Q P ) Bridge switches placed on the side (Q 3A , Q 4A , Q 1B and Q 2B ) can be controlled not to operate. That is, the first switch (Q P ) Bridge switches placed on the side (Q 3A , Q 4A , Q 1B and Q 2B ) can remain in the open state. The first primary winding (N PA ) and the second primary winding (N PB ) is the first switch (Q P ) are electrically connected in series, so the first primary winding (N PA ) and the second primary winding (N PB ) can be reduced. Accordingly, the magnitude of the voltage applied to the first primary winding (N PA ) voltage and the second primary winding (N PB) are induced by the voltage of the first secondary winding (N SA ) voltage and the second secondary winding (N SB ) can also be reduced in voltage. Therefore, the first switch (Q P ) is closed and the second switch (Q A ) is open, the output capacitor (C O ) is applied to the first switch (Q P ) and the second switch (Q A ) is open, the output capacitor (C O ) may be smaller than the first voltage applied to the device.

[0058] For example, the first switch (Q P ) is closed and the second switch (Q A ) is open, the output capacitor (C O ) is applied to the first switch (Q P ) and the second switch (Q A ) is open, the output capacitor (C O ) can have a size of about 1 / 2 times the first voltage applied to the circuit.

[0059] Fig. 3 is a circuit diagram illustrating a resonant converter according to one embodiment. Fig. 3 shows a first switch (Q P ) is opened and the second switch (Q A ) represents a resonant converter in the closed case.

[0060] As shown in Fig. 3, the first switch (Q P ) is opened and the second switch (Q A ) is closed, the output capacitor (C O ) has a first secondary winding (N SA ) and the voltage induced in the second secondary winding (N SB ) can be applied based on the voltage induced in the second switch (Q A ) by the first secondary winding (N SA ) and the second secondary winding (N SB) can be electrically connected in series, and a second switch (Q A ) Bridge diodes placed on the side (D R3A , D R4A , D R1B and D R2B ) may be in an electrically short-circuited state. Accordingly, the first secondary winding (N SA ) and the voltage induced in the second secondary winding (N SB ) based on the sum of the voltages induced in the output capacitor (C O ) can be applied with a third voltage. Therefore, the first switch (Q P ) is opened and the second switch (Q A ) is closed, the output capacitor (C O ) is applied to the first switch (Q P ) and the second switch (Q A ) is open, the output capacitor (C O ) may be greater than the first voltage applied to the device.

[0061] For example, the first switch (Q P ) is opened and the second switch (Q A ) is closed, the output capacitor (C O ) is applied to the first switch (Q P ) and the second switch (Q A ) is open, the output capacitor (C O ) can have a magnitude approximately twice that of the first voltage applied to the device.

[0062] Fig. 4 is a circuit diagram illustrating a resonant converter according to one embodiment. Fig. 4 shows a first switch (Q P ) and the second switch (Q A ) represents a resonant converter in the closed case.

[0063] As shown in Fig. 4, the first switch (Q P ) and the second switch (Q A ) is closed, the output capacitor (C O ) has a first secondary winding (NSA ) and the voltage induced in the second secondary winding (N SB ) can be applied based on the voltage induced in the first switch (Q). In addition, the fourth voltage can be applied based on the voltage induced in the first switch (Q P ) Bridge switches placed on the side (Q 3A , Q 4A , Q 1B and Q 2B ) can be controlled not to operate. That is, the first switch (Q P ) Bridge switches placed on the side (Q 3A , Q 4A , Q 1B and Q 2B ) can remain in the open state. Also, the second switch (Q A ) Bridge diodes placed on the side (D R3A , D R4A , D R1B and D R2B ) may be equivalent to an electrically shorted state.

[0064] First primary winding (N PA ) and the second primary winding (N PB ) is the first switch (Q P ) are electrically connected in series, so the first primary winding (N PA ) and the magnitude of the voltage applied to the second primary winding (N PB ) can be reduced in magnitude. The first primary winding (N PA ) and the second primary winding (N PB ) is reduced, the magnitude of the voltage applied to the first secondary winding (N SA ) and the second secondary winding (N SB ) can also be reduced. Therefore, the magnitude of the voltage induced in the first switch (Q P ) and the second switch (Q A ) is closed, the output capacitor (C O ) is applied to the first switch (Q P ) is opened and the second switch (Q A ) is closed, the output capacitor (CO ) may be smaller than the third voltage applied to the device.

[0065] Second switch (Q A ) by the first secondary winding (N SA ) and the second secondary winding (N SB ) are electrically connected in series, the first secondary winding (N SA ) and the voltage induced in the second secondary winding (N SB ) based on the sum of the voltages induced in the output capacitor (C O ) can be applied with a fourth voltage. Therefore, the first switch (Q P ) and the second switch (Q A ) is closed, the output capacitor (C O ) is applied to the first switch (Q P ) is closed and the second switch (Q A ) is open, the output capacitor (C O ) may be larger than the second voltage applied to the circuit.

[0066] 1st switch (Q P ) is closed, the first secondary winding (N SA ) and the voltage induced in the second secondary winding (N SB ) is reduced by the magnitude of the voltage induced in the second switch (Q A ) is closed, the first secondary winding (N SA ) and the voltage induced in the second secondary winding (N SB ) based on the sum of the voltages induced in the output capacitor (C O ) may be similar to the extent to which the magnitude of the voltage applied to the first switch (Q) increases. Therefore, the first switch (Q P ) and the second switch (Q A ) is closed, the output capacitor (C O ) is applied to the first switch (Q P ) and the second switch (Q A ) is open, the output capacitor (C O) may have a similar magnitude to the first voltage applied to the first switch (Q). However, the first switch (Q P ) and the second switch (Q A ) is closed, the first transformer (T A ) and the second transformer (T B ) The voltage or current stress applied to each of the first switches (Q P ) and the second switch (Q A ) can be reduced by half compared to when it is open.

[0067] According to the embodiments referring to FIGS. 1 to 4, the resonant converter (10) includes a first switch (Q P ) and the second switch (Q A ) can provide output voltages of various sizes depending on the open / closed state.

[0068] In the embodiments referring to FIGS. 1 to 4, the first switch (Q P ) and the second switch (Q A ) can each be a single switching element. Accordingly, the circuit configuration for providing output voltages of various sizes within the power conversion system can be simplified. In addition, the first switch (Q P ) and the second switch (Q A ) can increase reliability compared to when each is composed of multiple switches.

[0069] Fig. 5 is a circuit diagram illustrating a resonant converter according to another embodiment. Fig. 5 shows a switch (Q P ) represents a resonant converter when the open circuit is opened.

[0070] The resonant converter (50) comprises a first switching bridge, a first resonant tank, and a first primary winding (N PA ) may include a first input side circuit including a first switching bridge. In one embodiment, the first switching bridge comprises a plurality of bridge switches (Q) controlled by at least one switching signal. 1A , Q 2A , Q 3A and Q4A ) may be included. The first switching bridge may include a DC input voltage (V IN ) can generate a square wave output. The square wave output is generated by the first resonant tank and the first primary winding (N PA ) can be transmitted.

[0071] The first resonant tank is coupled to the first switching bridge and has a resonant inductor (L) connected in series. RA ) and resonant capacitor (C RA ) may be included. However, it is not necessarily limited thereto, and the first resonant tank may include a combination of at least one resonant inductor and at least one resonant capacitor connected in series or parallel.

[0072] The resonant converter (50) is connected in parallel with the first input side circuit, and includes a second switching bridge, a second resonant tank, and a second primary winding (N PB ) may include a second input side circuit including a second switching bridge. In one embodiment, the second switching bridge comprises a plurality of bridge switches (Q) controlled by at least one switching signal. 1B , Q 2B , Q 3B and Q 4B ) may be included. The second switching bridge may include a DC input voltage (V IN ) can generate a square wave output. The square wave output is generated by the second resonant tank and the second primary winding (N PB ) can be transmitted.

[0073] The second resonant tank is coupled to the second switching bridge and has a resonant inductor (L) connected in series. RB ) and resonant capacitor (C RB ) may be included. However, it is not necessarily limited thereto, and the second resonant tank may include a combination of at least one resonant inductor and at least one resonant capacitor connected in series or parallel.

[0074] Meanwhile, although FIG. 5 illustrates the first switching bridge and the second switching bridge as having a full bridge configuration each including four bridge switches, this is not necessarily limited thereto. At least one of the first switching bridge and the second switching bridge may also have a half bridge configuration including two bridge switches. Furthermore, at least one of the first switching bridge and the second switching bridge may have a full bridge configuration, but may operate in the same manner as a half bridge through control using a switching signal.

[0075] The resonant converter (50) has a first primary winding (N PA ) with the first transformer (T A ) constitutes the first secondary winding (N SA ), and a first output side circuit including a first rectifier network. A first transformer (T A ) is the first primary winding (N PA ) and first secondary winding (N SA ) can change the strength of the AC voltage in proportion to the turns ratio between the first input circuit and the first output circuit. The first resonant tank can form a first power conversion circuit. The first resonant tank can be a resonant inductor (L RA ) and resonant capacitor (C RA ) and includes a first transformer (T A ) has a magnetizing inductance, the first power conversion circuit may correspond to an LLC converter. The first rectifier network includes a plurality of bridge diodes (D) for converting AC input to DC output. R1A , D R2A , D R3A and D R4A ) may be included.

[0076] The resonant converter (50) is connected in parallel with the first output side circuit and the second primary winding (N PB ) with the second transformer (T B ) forming the second secondary winding (N SB), and a second output side circuit including a second rectifier network. A second transformer (T B ) is the second primary winding (N PB ) and the second secondary winding (N SB ) can change the strength of the AC voltage in proportion to the turns ratio between the input and output circuits. The second input circuit and the second output circuit can form a second power conversion circuit. The second resonant tank may include a resonant inductor (L RB ) and resonant capacitor (C RB ) and a second transformer (T B ) has a magnetizing inductance, the second power conversion circuit may correspond to an LLC converter. The second rectifier network includes a plurality of bridge diodes (D) for converting AC input to DC output. R1B , D R2B , D R3B and D R4B ) may be included.

[0077] The resonant converter (50) has a first primary winding (N PA ) and the second primary winding (N PB ) are electrically connected in series with a switch (Q) P ) may be included. In addition, the resonant converter (50) may include a switch (Q P ) may further include a control circuit for determining whether to open or close.

[0078] Switch (Q P ) may include at least one of a metal oxide semiconductor field effect transistor, a bipolar junction transistor, a gate turn-off thyristor, an integrated gate commutator thyristor, an insulated gate bipolar transistor, and a relay. However, the present invention is not limited thereto, and a switch (Q P ) may be another type of switch, including a two-way switch.

[0079] The resonant converter (50) has an output capacitor (C) shared by the first output side circuit and the second output side circuit. O) may include a switch (Q P ) depending on whether the output capacitor (C) is open or closed. O ) may vary in the range of output voltage applied.

[0080] As shown in Fig. 5, the switch (Q P ) is open, the first input-side circuit and the second input-side circuit can operate in parallel, the first output-side circuit and the second output-side circuit can operate in parallel, and the first power conversion circuit and the second power conversion circuit can operate in parallel. Accordingly, the output capacitor (C O ) can be applied with a fifth voltage based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit.

[0081] In one embodiment, the first power conversion circuit and the second power conversion circuit may operate in an interleaved manner to reduce current ripple. However, this is not necessarily limited. The first power conversion circuit and the second power conversion circuit may also operate in synchronization with the same timing by the same switching signals.

[0082] Fig. 6 is a circuit diagram illustrating a resonant converter according to another embodiment. Fig. 6 shows a switch (Q P ) represents a resonant converter in the closed case.

[0083] Referring to Fig. 6, the first input side circuit includes a first resonant tank and a first primary winding (N PA ) may include a first H-bridge circuit (H1) arranged on the center line. In addition, the second input side circuit may include a second resonant tank and a second primary winding (N PB ) may include a second H-bridge circuit (H2) arranged on the center line.

[0084] Bridge switches of the first switching bridge (Q 1A , Q 2A , Q 3A and Q 4A) can be placed in the four bridges of the first H-bridge circuit (H1), respectively. In addition, the bridge switches (Q) of the second switching bridge 1B , Q 2B , Q 3B and Q 4B ) can be placed on the four bridges of the second H-bridge circuit (H2). Switch (Q P ) can be arranged to connect the center lines of the first H-bridge circuit (H1) and the second H-bridge circuit (H2).

[0085] The resonant converter (50) is a switch (Q P ) may further include a switching controller configured to control the first and second switching bridges depending on the open / closed state of the first and second switching bridges.

[0086] Switch (Q P ) is open, the switching controller switches (Q P ) Bridge switches (Q) placed close to 3A , Q 4A , Q 1B and Q 2B ) can be controlled to remain in an open state. In addition, the switching controller can control the switch (Q P ) Bridge switches placed far apart (Q 1A , Q 2A , Q 3B and Q 4B ) is the DC input voltage (V IN ) can be controlled to generate a square wave output from the bridge switches (Q 1A , Q 2A , Q 3B and Q 4B ) is a square wave output generated by the first resonant tank, the first primary winding (N PA ), second resonant tank and second primary winding (N PB ) can be transmitted.

[0087] Switch (Q P ) is closed, the switching controller switches the bridge switches (Q) of the first switching bridge 1A , Q2A , Q 3A and Q 4A ) is the DC input voltage (V IN ) can be controlled to generate a square wave output from the bridge switches (Q 1A , Q 2A , Q 3A and Q 4A ) is generated by the first resonant tank and the first primary winding (N PA ) can be transmitted. In addition, the switching controller can be transmitted to the bridge switches (Q) of the second switching bridge. 1B , Q 2B , Q 3B and Q 4B ) is the DC input voltage (V IN ) can be controlled to generate a separate square wave output from the bridge switches (Q 1B , Q 2B , Q 3B and Q 4B ) is generated by the second resonant tank and the second primary winding (N PB ) can be transmitted.

[0088] As shown in Fig. 6, the switch (Q P ) is closed, the output capacitor (C O ) can be applied with a sixth voltage based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit. In addition, the switch (Q P ) Bridge switches placed on the side (Q 3A , Q 4A , Q 1B and Q 2B ) can be controlled not to operate, i.e. the switch (Q P ) Bridge switches placed on the side (Q 3A , Q 4A , Q 1B and Q 2B ) can remain in the open state. The first primary winding (N PA ) and the second primary winding (N PB ) is the switch (Q P) are electrically connected in series, so the first primary winding (N PA ) and the magnitude of the voltage applied to the second primary winding (N PB ) can be reduced in magnitude. The first primary winding (N PA ) and the second primary winding (N PB ) is reduced, the magnitude of the voltage applied to the first secondary winding (N SA ) and the magnitude of the voltage induced in the second secondary winding (N SB ) can also be reduced. Therefore, the switch (Q P ) is closed, the output capacitor (C O ) is applied to the switch (Q P ) is open, the output capacitor (C O ) may be smaller than the fifth voltage applied to the circuit.

[0089] Figure 7 is a block diagram of an electric vehicle charger according to one embodiment.

[0090] Referring to FIG. 7, the electric vehicle charger (70) may include an AC-DC converter (710), an electric reservoir (720), a DC-DC converter (730), and a control unit (740). However, the internal structure of the electric vehicle charger (70) is not limited to that illustrated in FIG. 7. Those skilled in the art will understand that, depending on the design of the electric vehicle charger (70), some of the hardware components illustrated in FIG. 7 may be omitted or new components may be added. For example, the electric vehicle charger (70) may further include a socket unit including terminals for electrically connecting an external device and the electric vehicle charger (70).

[0091] An electric vehicle charger (70) may refer to a rapid charger installed at an electric charging station, similar to a gasoline station. In one example, the electric vehicle charger (70) can charge an electric vehicle battery to 80% or more within one hour, and the charging capacity of the electric vehicle charger (70) may be 30 kW or more. However, this is not necessarily limited thereto.

[0092] The AC-DC converter (710) may refer to a converter that converts AC power received from an external power source into DC power. For example, the AC-DC converter (710) may convert AC power received from an external three-phase AC input power source into single-phase DC power. However, the present invention is not limited thereto. Instead of being directly connected to an external three-phase AC input power source, the AC-DC converter (710) may be connected to an external three-phase AC input power source through a separate three-phase transformer, etc., thereby receiving single-phase AC power and converting it into DC power.

[0093] The electric reservoir (720) can store direct current power received from the AC-DC converter (710). The electric reservoir (720) can act as a buffer during the process of transmitting power from the AC-DC converter (710) to the DC-DC converter (730). The electric reservoir (720) can include, but is not limited to, one or more battery packs.

[0094] The DC-DC converter (730) may refer to a converter that converts input DC power into DC power with a different voltage and outputs it. For example, the DC-DC converter (730) may convert DC power received from the AC-DC converter (710) or the electric reservoir (720) into DC power with a different voltage. The DC-DC converter (730) may be a resonant converter (10) of FIGS. 1 to 4 or a resonant converter (50) of FIGS. 5 and 6.

[0095] The control unit (740) is hardware that controls the overall operation of the electric vehicle charger (70). For example, the control unit (740) can control the operation of the AC-DC converter (710), the electric reservoir (720), and the DC-DC converter (730), as well as other components included in the electric vehicle charger (70).

[0096] The control unit (740) includes at least one processor. The processor may be implemented as an array of multiple logic gates, or as a combination of a general-purpose microprocessor and a memory storing a program executable on the microprocessor. Furthermore, those skilled in the art will appreciate that the processor may be implemented using other types of hardware.

[0097] In one embodiment, the DC-DC converter (730) may include a first input-side circuit including a first switching bridge, a first resonant tank, and a first primary winding. The DC-DC converter (730) may also include a second input-side circuit connected in parallel with the first input-side circuit, the second input-side circuit including a second switching bridge, a second resonant tank, and a second primary winding. The DC-DC converter (730) may include a first output-side circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first rectifier network. The DC-DC converter (730) may also include a second output-side circuit connected in parallel with the first output-side circuit, the second secondary winding forming a second transformer together with the second primary winding, and a second rectifier network.

[0098] In one embodiment, the DC-DC converter (730) may include a first switch connecting the first primary winding and the second primary winding, a second switch connecting the first secondary winding and the second secondary winding, and an output capacitor shared by the first output-side circuit and the second output-side circuit.

[0099] In one embodiment, the magnitude of the voltage applied to the output capacitor may vary depending on the open / closed states of the first switch and the second switch.

[0100] When the first switch is closed, the first primary winding and the second primary winding are electrically connected in series, so that the magnitudes of the voltages applied to the first primary winding and the voltages applied to the second primary winding can be reduced. Accordingly, the second voltage applied to the output capacitor when the first switch is closed and the second switch is open can be smaller in magnitude than the first voltage applied to the output capacitor when the first switch and the second switch are open. In addition, the fourth voltage applied to the output capacitor when the first switch and the second switch are closed can be smaller in magnitude than the third voltage applied to the output capacitor when the first switch is open and the second switch is closed.

[0101] When the second switch is closed, the first secondary winding and the second secondary winding are electrically connected in series, so that a voltage can be applied to the output capacitor based on the sum of the voltage induced in the first secondary winding and the voltage induced in the second secondary winding. Accordingly, the third voltage applied when the first switch is open and the second switch is closed can be larger in magnitude than the first voltage applied to the output capacitor when the first switch and the second switch are open. In addition, the fourth voltage applied to the output capacitor when the first switch and the second switch are closed can be larger in magnitude than the second voltage applied to the output capacitor when the first switch is closed and the second switch is open.

[0102] In another embodiment, the DC-DC converter (730) may include a switch connecting the first primary winding and the second primary winding, and an output capacitor shared by the first output-side circuit and the second output-side circuit.

[0103] In another embodiment, the magnitude of the voltage applied to the output capacitor may vary depending on the open / closed state of the switch.

[0104] When the switch is closed, the first primary winding and the second primary winding are electrically connected in series, so that the magnitude of the voltage applied to the first primary winding and the magnitude of the voltage applied to the second primary winding can be reduced. Accordingly, the sixth voltage applied to the output capacitor when the switch is closed can be smaller in magnitude than the fifth voltage applied to the output capacitor when the switch is open.

[0105] In this way, the electric vehicle charger (70) according to the present disclosure can provide a wide range of output voltages using the DC-DC converter (730). By using the first switch arranged between the primary windings of the input circuits and the second switch arranged between the secondary windings of the output circuits, the circuit configuration for providing output voltages of various magnitudes can be simplified. In addition, since the first and second switches are each configured as a single switch, reliability can be increased compared to when the first and second switches are each configured as a plurality of switches.

[0106] The description of the above-described embodiments is merely illustrative, and those skilled in the art will appreciate that various modifications and equivalent alternative embodiments are possible. Therefore, the true scope of protection for the invention should be defined by the appended claims, and all differences within the scope equivalent to the claims should be construed as being included within the scope of protection defined by the claims.

Claims

1. In a resonant converter for an electric vehicle charger, A first input side circuit including a first switching bridge, a first resonant tank, and a first primary winding; A second input side circuit connected in parallel with the first input side circuit and including a second switching bridge, a second resonant tank, and a second primary winding; A first switch configured to electrically connect the first primary winding and the second primary winding in series; A first output circuit including a first secondary winding constituting a first transformer together with the first primary winding, and a first rectifier network; A second output-side circuit including a second secondary winding connected in parallel with the first output-side circuit and forming a second transformer together with the second primary winding, and a second rectifier network; a second switch configured to electrically connect the first secondary winding and the second secondary winding in series; and A resonant converter comprising an output capacitor connected in parallel with the first output side circuit and the second output side circuit.

2. In paragraph 1, When the first switch is opened and the second switch is opened, a first voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, When the first switch is closed and the second switch is opened, a second voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, A resonant converter, wherein the magnitude of the second voltage is smaller than the magnitude of the first voltage.

3. In paragraph 2, When the first switch is opened and the second switch is closed, a third voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, A resonant converter wherein the magnitude of the third voltage is greater than the magnitude of the first voltage.

4. In paragraph 3, When the first switch is closed and the second switch is closed, a fourth voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, A resonant converter wherein the magnitude of the fourth voltage is greater than the magnitude of the second voltage and less than the magnitude of the third voltage.

5. In paragraph 1, The above first input side circuit is a first H-bridge circuit in which the first resonant tank and the first primary winding are arranged on the center line, A resonant converter, wherein the second input side circuit is a second H-bridge circuit in which the second resonant tank and the second primary winding are arranged on the center line.

6. In paragraph 5, A resonant converter, wherein the first switch is configured to connect the center line of the first H-bridge circuit and the center line of the second H-bridge circuit.

7. In paragraph 6, The first switching bridge includes four bridge switches each arranged in the bridges of the first H-bridge circuit, A resonant converter, wherein the second switching bridge comprises four bridge switches each arranged in the bridges of the second H-bridge circuit.

8. In paragraph 7, A resonant converter configured such that when the first switch is closed, two bridge switches arranged on the first switch side among the four bridge switches of the first switching bridge and two bridge switches arranged on the first switch side among the four bridge switches of the second switching bridge are opened.

9. In paragraph 1, A resonant converter, wherein the first resonant tank and the first primary winding are electrically connected in series, and the second resonant tank and the second primary winding are electrically connected in series.

10. In a resonant converter for an electric vehicle charger, A first input side circuit including a first switching bridge, a first resonant tank and a first primary winding; A second input side circuit connected in parallel with the first input side circuit and including a second switching bridge, a second resonant tank, and a second primary winding; A switch configured to electrically connect the first primary winding and the second primary winding in series; A first output side circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first rectifier network; A second output-side circuit including a second secondary winding connected in parallel with the first output-side circuit and forming a second transformer together with the second primary winding, and a second rectifier network; and A resonant converter comprising an output capacitor connected in parallel with the first output side circuit and the second output side circuit.

11. In paragraph 10, When the switch is opened, a fifth voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, When the switch is closed, a sixth voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, A resonant converter wherein the magnitude of the sixth voltage is smaller than the magnitude of the fifth voltage.

12. In paragraph 10, The above first input side circuit is a first H-bridge circuit in which the first resonant tank and the first primary winding are arranged on the center line, A resonant converter, wherein the second input side circuit is a second H-bridge circuit in which the second resonant tank and the second primary winding are arranged on the center line.

13. In paragraph 12, A resonant converter, wherein the switch is configured to connect the center line of the first H-bridge circuit and the center line of the second H-bridge circuit.

14. In paragraph 13, The first switching bridge includes four bridge switches each arranged in the bridges of the first H-bridge circuit, A resonant converter, wherein the second switching bridge comprises four bridge switches each arranged in the bridges of the second H-bridge circuit.

15. In paragraph 14, A resonant converter configured such that when the switch is closed, two bridge switches arranged on the switch side among the four bridge switches of the first switching bridge and two bridge switches arranged on the switch side among the four bridge switches of the second switching bridge are opened.

16. In electric vehicle chargers, AC-DC converter that converts AC power received from an external power source into DC power; An electric reservoir for storing direct current power received from the AC-DC converter; A DC-DC converter that converts the DC power received from the AC-DC converter or the electric reservoir into DC power having a different voltage; and It includes a control unit that controls the AC-DC converter, the electric reservoir, and the DC-DC converter, The above DC-DC converter, A first input side circuit including a first switching bridge, a first resonant tank and a first primary winding; A second input side circuit connected in parallel with the first input side circuit and including a second switching bridge, a second resonant tank, and a second primary winding; A first switch configured to electrically connect the first primary winding and the second primary winding in series; A first output side circuit including a first secondary winding forming a first transformer together with the first primary winding, and a first rectifier network; A second output-side circuit including a second secondary winding connected in parallel with the first output-side circuit and forming a second transformer together with the second primary winding, and a second rectifier network; a second switch connecting the first secondary winding and the second secondary winding; and An electric vehicle charger comprising an output capacitor connected in parallel with the first output side circuit and the second output side circuit.

17. In paragraph 16, When the first switch is opened and the second switch is opened, a first voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, When the first switch is closed and the second switch is opened, a second voltage is applied to the output capacitor based on the output voltage of the first output-side circuit and the output voltage of the second output-side circuit, An electric vehicle charger, wherein the magnitude of the second voltage is smaller than the magnitude of the first voltage.

18. In paragraph 17, When the first switch is opened and the second switch is closed, a third voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, An electric vehicle charger, wherein the magnitude of the third voltage is greater than the magnitude of the first voltage.

19. In paragraph 18, When the first switch is closed and the second switch is closed, a fourth voltage is applied to the output capacitor based on the voltage of the first secondary winding and the voltage of the second secondary winding, An electric vehicle charger, wherein the magnitude of the fourth voltage is greater than the magnitude of the second voltage and less than the magnitude of the third voltage.

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