LLC resonant conversion circuit, charging device, energy storage device and electric device

Abstract

The application provides an LLC resonant conversion circuit, a charging device, an energy storage device and a power utilization device, and relates to the technical field of power electronics. The LLC resonant conversion circuit is composed of multiple harmonic circuits. Multiple transformers in each harmonic circuit are electrically connected with each other and electrically connected with a transformer of another harmonic circuit, so that the harmonic circuits are crossed with each other, the electric signal of one harmonic circuit can be shunted or divided into another harmonic circuit, and under the premise of not adding any device, the current value of the electric signal of each harmonic circuit is the same when the harmonic circuits are connected in parallel, and the voltage value of the electric signal of each harmonic circuit is the same when the harmonic circuits are connected in series, the complexity of the control strategy of the whole LLC resonant conversion circuit is effectively reduced, and the cost of the LLC resonant conversion circuit is reduced.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and in particular to an LLC resonant converter circuit, a charging device, an energy storage device, and an electrical appliance. Background Technology

[0002] With the development of the electric vehicle industry, battery charging speed is currently one of the main factors restricting the development of electric vehicles. To improve the charging speed of electric vehicles, higher-power DC charging piles can be configured, and the core power unit of the charging pile is the charging module. Traditional charging modules generally use AC / DC rectifier units or DC / DC rectifier units, but with increasingly higher requirements for current conversion efficiency and heat dissipation performance, existing rectifier circuits cannot meet the requirements. LLC (an abbreviation for Lr, Lm, and Cr, where Lr is the resonant inductor, Lm is the magnetizing inductor, and Cr is the resonant capacitor) resonant converters have advantages such as high switching frequency, low turn-off loss, high conversion efficiency, low electromagnetic interference noise, and low switching stress, and are therefore widely used in charging piles.

[0003] However, the output power of LLC resonant converters is limited, generally suitable for low- to medium-power products. To achieve higher output power for the charging module, two or more LLC resonant converters can be connected in parallel or series. However, if multiple LLC resonant converters are connected in parallel, current sharing is required for each converter. If multiple LLC resonant converters are connected in series, voltage sharing is required for each converter. To address the issue of different currents when LLC resonant converters are connected in parallel and different voltages when they are connected in series, resulting in different resonant parameters of the output electrical signal, current sharing or voltage sharing circuits are generally added to the circuit composed of multiple LLC resonant converters. This undoubtedly increases the cost of the entire circuit and makes the control strategy of the entire circuit more complex. Summary of the Invention

[0004] To address the aforementioned issues, embodiments of this application provide an LLC resonant converter circuit, a charging device, an energy storage device, and an electrical appliance. By allowing the transformers of each resonant circuit in the LLC resonant converter circuit to cross each other, the entire LLC resonant converter circuit can autonomously equalize voltage when connected in series and autonomously equalize current when connected in parallel, without the need for additional circuitry. This effectively reduces the complexity of the control strategy for the entire LLC resonant converter circuit and lowers its cost.

[0005] Therefore, the following technical solutions are adopted in the embodiments of this application:

[0006] In a first aspect, this application provides an LLC resonant converter circuit, comprising: N harmonic circuits, where N is a positive integer greater than or equal to 2; each harmonic circuit includes a switching circuit, an LC resonant circuit, a transformer circuit, and a rectifier circuit connected in sequence; the transformer circuit includes at least three transformers, each transformer including a first winding and a second winding; wherein, one end of the first winding of at least two transformers of the transformer circuit of the first harmonic circuit is electrically connected to the LC resonant circuit of the first harmonic circuit, the other end is electrically connected to each other, and is electrically connected to one end of the first winding of one transformer of the transformer circuit of another harmonic circuit, the other harmonic circuit being harmonic circuits other than the first harmonic circuit among the N harmonic circuits; or one end of the second winding of at least two transformers of the transformer circuit of the first harmonic circuit is electrically connected to the rectifier circuit of the first harmonic circuit, the other end is electrically connected to each other, and is electrically connected to one end of the second winding of one transformer of the transformer circuit of another harmonic circuit.

[0007] In this embodiment, the circuit consists of multiple harmonic circuits, each containing multiple transformers that are electrically connected to each other and to a transformer in another harmonic circuit. This allows the harmonic circuits to cross over each other, enabling the electrical signal of one harmonic circuit to be shunted or divided into another. Without adding any components, the circuits achieve the same current value when connected in parallel and the same voltage value when connected in series. This effectively reduces the complexity of the control strategy for the entire LLC resonant converter circuit and lowers its cost.

[0008] In one embodiment, when the switching circuits of each harmonic circuit are connected in parallel, one end of the first winding of at least two transformers in the first transformer circuit is electrically connected to the first LC resonant circuit, and the other ends of the first windings of the at least two transformers are electrically connected to each other and to one end of the first winding of the first transformer in the second transformer circuit; the other end of the first winding of the first transformer is electrically connected to the first LC resonant circuit; one end of the first winding of at least two transformers other than the first transformer in the second transformer circuit is electrically connected to the second LC resonant circuit, and the other ends of the first windings of the at least two transformers other than the first transformer in the second transformer circuit are electrically connected to each other and to one end of the first winding of the second transformer in the first transformer circuit; the other end of the first winding of the second transformer is electrically connected to the second LC resonant circuit; wherein, the first harmonic circuit includes the first LC resonant circuit and the first transformer circuit, the second transformer is one of the transformers in the first transformer circuit other than the at least two transformers, the other harmonic circuits include the second harmonic circuit, and the second harmonic circuit includes the second LC resonant circuit and the second transformer circuit.

[0009] In this implementation, when the switching circuits in the N harmonic circuits are connected in parallel, one end of the primary winding of the two transformers in the transformer circuit of one harmonic circuit is electrically connected to the LC resonant circuit, and the other end is electrically connected to each other. They are also electrically connected to the primary winding of one transformer in the transformer circuit of other harmonic circuits. This makes the current value of the two transformers in this harmonic circuit equal to the current value of one transformer in each of the other harmonic circuits. Then, the current values ​​of each transformer in each harmonic circuit are accumulated, and the current value output by the rectifier circuit of each harmonic circuit is the same. This achieves autonomous current splitting of the electrical signal of each harmonic circuit without adding any components.

[0010] In one embodiment, in the first transformer circuit, one end of the second winding of at least three transformers is electrically connected to the first rectifier circuit, and the other ends of the second windings of the at least three transformers are electrically connected to each other; in the second transformer circuit, one end of the second winding of at least three transformers is electrically connected to the second rectifier circuit, and the other ends of the second windings of the at least three transformers are electrically connected to each other; wherein, the first harmonic circuit includes the first rectifier circuit, and the second harmonic circuit includes the second rectifier circuit.

[0011] In this embodiment, by connecting the second windings of each transformer in parallel to the rectifier circuit, the output current value of each transformer is the same. This avoids the situation where the current on the secondary windings of each transformer is different, which would lead to different current on the primary windings and thus affect the autonomous current shunting of the entire circuit.

[0012] In one implementation, the rectifier circuits of each harmonic circuit are connected in series or in parallel.

[0013] In this embodiment, by connecting the rectifier circuits in parallel, the current value of the entire LLC resonant converter circuit can be increased; by connecting the rectifier circuits in series, the voltage value of the entire LLC resonant converter circuit can be increased.

[0014] In one embodiment, when the switching circuits of each harmonic circuit are connected in series or parallel, one end of the second winding of at least two transformers in the first transformer circuit is electrically connected to the first rectifier circuit, and the other ends of the second windings of the at least two transformers are electrically connected to each other and to one end of the second winding of the first transformer in the second transformer circuit; the other end of the second winding of the first transformer is electrically connected to the first rectifier circuit; one end of the second winding of at least two transformers other than the first transformer in the second transformer circuit is electrically connected to the second rectifier circuit, and the other ends of the second windings of the at least two transformers other than the first transformer in the second transformer circuit are electrically connected to each other and to one end of the second winding of the second transformer in the first transformer circuit; the other end of the second winding of the second transformer is electrically connected to the second rectifier circuit; wherein, the first harmonic circuit includes the first transformer circuit and the first rectifier circuit, the second transformer is one of the transformers in the first transformer circuit other than the at least two transformers, the other harmonic circuits include the second harmonic circuit, and the second harmonic circuit includes the second transformer circuit and the second rectifier circuit.

[0015] In this implementation, when the switching circuits in N harmonic circuits are connected in parallel, one end of the secondary windings of the two transformers in the transformer circuit of one harmonic circuit can be electrically connected to the rectifier circuit. The other end is electrically connected to each other and to the secondary winding of one transformer in the transformer circuit of another harmonic circuit. This makes the current value of the two transformers in this harmonic circuit equal to the current value of one transformer in each of the other harmonic circuits. Then, the current values ​​of each transformer in each harmonic circuit are summed, resulting in the same current value output by the rectifier circuit of each harmonic circuit. This achieves autonomous current splitting of the electrical signal in each harmonic circuit without adding any components.

[0016] When switching circuits are connected in series in N harmonic circuits, one end of the secondary windings of the two transformers in the transformer circuit of one harmonic circuit is electrically connected to the rectifier circuit, and the other end is electrically connected to each other. They are also electrically connected to the secondary windings of one transformer in the transformer circuits of other harmonic circuits. This makes the voltage value across the two transformers in this harmonic circuit equal to the voltage value across the transformers in each of the other harmonic circuits. Then, the voltage values ​​of each transformer in each harmonic circuit are summed, resulting in the same output voltage value of the rectifier circuit in each harmonic circuit. This achieves autonomous voltage division of the electrical signal in each harmonic circuit without adding any components.

[0017] In one embodiment, in the first transformer circuit, one end of the first winding of at least three transformers is electrically connected to a first LC resonant circuit, and the other ends of the first windings of the at least three transformers are electrically connected to each other; in the second transformer circuit, one end of the first winding of at least three transformers is electrically connected to a second LC resonant circuit, and the other ends of the first windings of the at least three transformers are electrically connected to each other; wherein, the first harmonic circuit includes the first LC resonant circuit, and the second harmonic circuit includes the second LC resonant circuit.

[0018] In this embodiment, by connecting the first windings of each transformer in parallel to the LC resonant circuit, the current and voltage values ​​input to the second winding of each transformer are the same. This avoids the situation where different currents or voltages on the first windings of each transformer lead to different currents or voltages on the second windings, thus affecting the autonomous current shunting or voltage division of the entire circuit.

[0019] In one implementation, the rectifier circuits of each harmonic circuit are connected in parallel.

[0020] In this embodiment, by connecting the various rectifier circuits in parallel, the current value of the entire LLC resonant converter circuit can be increased.

[0021] In one implementation, the transformers in each transformer circuit are identical.

[0022] In this implementation, by making the transformers in each transformer circuit identical, the voltage and current values ​​input to the secondary side of each transformer are guaranteed to be the same.

[0023] In one implementation, the at least three transformers in each transformer circuit share a single iron core.

[0024] In this implementation, by having each transformer share a single core, the different core impedances of different transformers are avoided, which would result in the same voltage and current values ​​input to the secondary side of each transformer.

[0025] In one implementation, the second winding of each transformer circuit includes multiple sub-windings.

[0026] In one embodiment, each second winding of each transformer circuit includes at least a first sub-winding and a second sub-winding, and each transformer circuit also includes at least two switches, which are used to connect the first sub-winding of each second winding of each transformer circuit in series with the second sub-winding of each second winding of the transformer circuit in a first state; and to disconnect the second sub-winding of each second winding of each transformer circuit in a second state.

[0027] In one embodiment, each transformer circuit includes a first transformer, a second transformer, and a third transformer. The at least two switches include a first switch and a second switch, each of which includes three nodes. Each second winding of each transformer circuit includes a first sub-winding and a second set of windings. One end of the first sub-winding of the first transformer is electrically connected to the rectifier circuit of the harmonic circuit; the other end of the first sub-winding of the first transformer is electrically connected to the first interface of the first switch; one end of the second sub-winding of the first transformer is electrically connected to the second interface of the first switch; and the other end of the second sub-winding of the first transformer is respectively connected to one interface of the second sub-winding of the second transformer. One end of the first sub-winding of the second transformer is electrically connected to one end of the second sub-winding of the third transformer; one end of the first sub-winding of the second transformer is electrically connected to the rectifier circuit of the harmonic circuit; the other end of the first sub-winding of the second transformer is electrically connected to the other end of the second sub-winding of the second transformer; the other end of the second sub-winding of the second transformer, the third interface of the first switch, and the third interface of the second switch are electrically connected to each other; one end of the first sub-winding of the third transformer is electrically connected to the rectifier circuit of the harmonic circuit; the other end of the first sub-winding of the third transformer is electrically connected to the first interface of the second switch; one end of the second sub-winding of the third transformer is electrically connected to the second interface of the second switch.

[0028] In one implementation, the number of turns in the multiple sub-windings of the second winding of each transformer circuit is the same.

[0029] In one embodiment, the system further includes a control circuit electrically connected between the two rectifier circuits, configured to connect the outputs of the two rectifier circuits in parallel when in a first state, and to connect the outputs of the two rectifier circuits in series when in a second state.

[0030] Secondly, this application provides a two-way three-phase LLC resonant converter circuit, comprising: a first harmonic circuit and a second harmonic circuit. The first harmonic circuit includes a first switching circuit, a first LC resonant circuit, a first transformer circuit, and a first rectifier circuit connected in sequence. The second harmonic circuit includes a second switching circuit, a second LC resonant circuit, a second transformer circuit, and a second rectifier circuit connected in sequence. The first switching circuit and the second switching circuit are connected in series. Each switching circuit includes three output ports. Each LC resonant circuit includes three resonant inductors and three resonant capacitors, with each resonant inductor connected in series with each resonant capacitor. Each transformer circuit includes three transformers, each transformer including a first winding and a second winding. Each rectifier circuit includes three input ports. The three output ports of the first switching circuit are connected in series with the three resonant inductors and three resonant capacitors of the first LC resonant circuit, respectively. Two of the three resonant capacitors are electrically connected to one end of the first winding of the two transformers of the first transformer circuit. The other ends of the first windings of the two transformers of the first transformer circuit are electrically connected to each other and to the second transformer. One end of the first winding of one of the three transformers in the circuit is electrically connected; one end of the first winding of the other transformer in the first transformer circuit is electrically connected to one of the three resonant capacitors in the second LC resonant circuit, and the other end of the first winding of the other transformer in the first transformer circuit is electrically connected to one end of the first winding of the other two transformers in the second transformer circuit; one end of the second winding of each of the three transformers in the first transformer circuit is electrically connected to one of the three input ports of the first rectifier circuit, and the other ends of the second windings of the three transformers in the first transformer circuit are electrically connected to each other; the three output ports of the second switching circuit are connected in series with the three resonant inductors and three resonant capacitors of the second LC resonant circuit; the other two resonant capacitors of the second LC resonant circuit are electrically connected to the other ends of the first windings of the other two transformers in the second transformer circuit; one end of the second winding of each of the three transformers in the second transformer circuit is electrically connected to one of the three input ports of the second rectifier circuit, and the other ends of the second windings of the three transformers in the second transformer circuit are electrically connected to each other.

[0031] Thirdly, this application provides a two-way three-phase LLC resonant converter circuit, comprising: a first harmonic circuit and a second harmonic circuit. The first harmonic circuit includes a first switching circuit, a first LC resonant circuit, a first transformer circuit, and a first rectifier circuit connected in sequence. The second harmonic circuit includes a second switching circuit, a second LC resonant circuit, a second transformer circuit, and a second rectifier circuit connected in sequence. Each switching circuit includes three output ports. Each LC resonant circuit includes three resonant inductors and three resonant capacitors, with each resonant inductor connected in series with each resonant capacitor. Each transformer circuit includes three transformers, each transformer including a first winding and a second winding. Each rectifier circuit includes three input ports. The three output ports of the first switching circuit are connected in series with the three resonant inductors and three resonant capacitors of the first LC resonant circuit, respectively. The three resonant capacitors are electrically connected to one end of the first winding of each of the three transformers in the first transformer circuit, and the other ends of the first windings of the three transformers in the first transformer circuit are electrically connected to each other. One end of the second winding of each of the two transformers in the first transformer circuit is electrically connected to the two input ports of the three input ports of the first rectifier circuit, respectively. The other ends of the second windings of two of the three transformers in the transformer circuit are electrically connected to each other and to one end of the second winding of one of the three transformers in the second transformer circuit. One end of the second winding of the other transformer in the first transformer circuit is electrically connected to one input port of the three input ports in the second rectifier circuit, and the other end of the second winding of the other transformer in the first transformer circuit is electrically connected to one end of the second winding of the other two transformers in the second transformer circuit. The three output ports of the second switching circuit are connected in series with the three resonant inductors and three resonant capacitors of the second LC resonant circuit. The three resonant capacitors are electrically connected to one end of the first winding of each of the three transformers in the second transformer circuit, and the other ends of the first windings of the three transformers in the second transformer circuit are electrically connected to each other. The other end of the second winding of one of the three transformers in the second transformer circuit is electrically connected to one input port of the three input ports in the first rectifier circuit, and the other ends of the second windings of the other two transformers in the second transformer circuit are electrically connected to the other two input ports of the three input ports in the second rectifier circuit.

[0032] Fourthly, this application provides a charging device, including at least one LLC resonant converter circuit as possibly implemented in the first aspect.

[0033] Fifthly, this application provides an energy storage device, comprising: a battery; at least one LLC resonant converter circuit as may be implemented in the first aspect, wherein the LLC resonant converter circuit is electrically connected to the battery and is used to process electrical signals input into the battery and input them into the battery.

[0034] In a sixth aspect, an embodiment of this application provides an electrical device, characterized in that it includes: at least one electrical component; at least one LLC resonant converter circuit as may be implemented in the first aspect, wherein the at least one LLC resonant converter circuit is electrically connected to the at least one electrical component and is used to process electrical signals input into the at least one electrical component and input them into the at least one electrical component. Attached Figure Description

[0035] The accompanying drawings used in the description of the embodiments or prior art are briefly introduced below.

[0036] Figure 1 This is a schematic diagram of the architecture of an LLC resonant converter circuit provided in an embodiment of this application;

[0037] Figure 2 This is a circuit diagram of the switching circuit in a two-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0038] Figure 3 This is a circuit diagram of the switching circuit in a two-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0039] Figure 4 This is a circuit diagram of the switching circuit in a two-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0040] Figure 5 This is a circuit diagram of the switching circuit in a two-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0041] Figure 6 This is a circuit diagram of the switching circuit in an N-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0042] Figure 7 This is a circuit diagram of the switching circuit in a two-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0043] Figure 8 This is a circuit diagram of the switching circuit in an N-channel three-phase LLC resonant converter circuit provided in an embodiment of this application;

[0044] Figure 9This is a circuit diagram of the switching circuit in a 2N-channel three-phase LLC resonant converter circuit provided in an embodiment of this application. Detailed Implementation

[0045] The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings.

[0046] In this article, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The symbol " / " in this article indicates that the related objects are in an "or" relationship; for example, A / B means A or B.

[0047] The terms "first" and "second," etc., used in this specification and claims are used to distinguish different objects, not to describe a specific order of objects. For example, "first response message" and "second response message," etc., are used to distinguish different response messages, not to describe a specific order of response messages.

[0048] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0049] In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more, for example, multiple processing units means two or more processing units, multiple elements means two or more elements, etc.

[0050] Figure 1 This is a schematic diagram of the architecture of an LLC resonant converter circuit provided in an embodiment of this application. Figure 1 As shown, the LLC resonant converter circuit protected in this application may include N harmonic circuits (100, 200, ..., N00), where N is a positive integer greater than or equal to 2. Each harmonic circuit (100, 200, ..., N00) includes a switching circuit (101, 201, ..., N-1), an LC resonant circuit (102, 202, ..., N-2), a transformer circuit (103, 203, ..., N-3), and a rectifier circuit (104, 204, ..., N-4).

[0051] In each harmonic circuit (100, 200, ..., N00), the switching circuit, LC resonant circuit, transformer circuit, and rectifier circuit are connected in sequence. This allows the electrical signal input from the external circuit to pass through the switching circuit, LC resonant circuit, transformer circuit, and rectifier circuit in sequence, thereby increasing the current or voltage value of the input electrical signal and thus increasing the power of the input electrical signal.

[0052] Each harmonic circuit (100, 200, ..., N00) can be connected in parallel or in series. Specifically, the switching circuits (101, 201, ..., N-1) of each harmonic circuit (100, 200, ..., N00) can connect their positive terminals together and their negative terminals together, thus connecting the harmonic circuits in parallel. Alternatively, the positive terminal of one switching circuit can be connected to the negative terminal of a switching circuit on one side, and the negative terminal of that switching circuit can be connected to the positive terminal of a switching circuit on the other side, and so on, thus connecting the harmonic circuits in series.

[0053] The switching circuit (101, 201, ..., N-1) typically establishes a communication connection with an external controller. By receiving control commands from the controller, it controls whether the electrical signal input to the harmonic circuit is turned on, and converts the input DC signal into a square wave signal. For example, as shown... Figure 2 As shown, the switching circuit 101 is a three-phase switching circuit, which may include a first switching transistor Q. 11 Second switch Q 12 The third switch Q 13 The fourth switch Q 14 Fifth switch Q 15 and the sixth switch Q 16 and input capacitor C 11 Among them, the first switching transistor Q 11 Second switch Q 12 Connected in series between them, and in the first switching transistor Q 11 Second switch Q 12 An output port P is electrically connected between them. 11 It can be electrically connected to the LC resonant circuit 102; the third switch Q 13 and the fourth switch Q 14 Connected in series between them, and in the third switch Q 13 and the fourth switch Q 14 An output port P is electrically connected between them. 12 It can be electrically connected to the LC resonant circuit 102; the fifth switch Q 15 and the sixth switch Q 16 Connected in series between them, and in the fifth switch Q 15 and the sixth switch Q16 An output port P is electrically connected between them. 13 It can be electrically connected to the LC resonant circuit 102. Each set of switching transistors and input capacitor C 11 They are connected in parallel, with input capacitor C 11 The input electrical signal is filtered, and then the upper and lower switching transistors of each group of switching transistors are alternately turned on to convert the filtered DC signal into a square wave signal, so that the three output ports P can output three square wave signals.

[0054] Optionally, the switching transistor of the switching circuit can be composed of one or more metal-oxide-semiconductor field-effect transistors (MOS). The controller controls whether the gate of each MOS is energized by connecting to the gate of each MOS, so as to realize that the switching transistor is in the on state or the off state.

[0055] In this application, the switching circuit 101 is only a three-phase switching circuit as an example. It can also be a two-phase switching circuit, etc., depending on actual product requirements. This application does not impose any limitations on this. Furthermore, the circuit structures of other switching circuits (201, ..., N-1) are generally the same as those of switching circuit 101. Of course, they can also differ from those of switching circuit 101 depending on actual product requirements. This application does not impose any limitations on this either.

[0056] An LC resonant circuit (102, 202, ..., N-2) can be connected in series with a transformer circuit (103, 203, ..., N-3) to form an LLC resonant circuit. In each transformer circuit, at least one primary winding (the coil winding electrically connected to the LC resonant circuit) can be cross-connected to the primary winding of at least one transformer in another transformer circuit, or at least one secondary winding (the coil winding electrically connected to the rectifier circuit) can be cross-connected to the secondary winding of at least one transformer in another transformer circuit. This allows the electrical signal of one harmonic circuit to be shunted to one or more other harmonic circuits, achieving current sharing for the electrical signals of each harmonic circuit when they are connected in parallel, and voltage sharing for the electrical signals of each harmonic circuit when they are connected in series.

[0057] For example, combined Figure 2 As shown, the LC resonant circuit 102 includes three resonant inductors (L... 11 L 12 L 13 ) and three resonant capacitors (C 12 C13 C 14 The transformer circuit 103 includes three transformers (T). 11 T 12 T 13 Among them, the resonant inductance L 11 With resonant capacitor C 12 Series connection, and resonant inductance L 11 The other end is connected to the output port P 11 Electrically connected, forming an LC resonant circuit; resonant inductor L 12 With resonant capacitor C 13 Series connection, and resonant inductance L 12 The other end is connected to the output port P 12 Electrically connected, forming an LC resonant circuit; resonant inductor L 13 With resonant capacitor C 14 Series connection, and resonant inductance L 13 The other end is connected to the output port P 13 The electrical connections form a set of LC resonances.

[0058] In transformer circuit 103, the primary winding of each transformer T can be connected in series with the resonant capacitor C of LC resonant circuit 102, or in series with the resonant capacitor C of other harmonic circuits (202, ..., N02) to form LLC resonant circuit. Each harmonic circuit with its resonant inductor L connected in series with its resonant capacitor C can be connected in series with the primary windings of transformers of different harmonic circuits. This ensures that when the switching circuits are connected in parallel, the current of each harmonic circuit is evenly distributed across the different harmonic circuits, making the current value of the output electrical signal of each harmonic circuit the same. The secondary winding of each transformer T in each transformer circuit can be connected in series with the rectifier circuit of the corresponding harmonic circuit.

[0059] In transformer circuit 103, the secondary winding of each transformer T can be connected in series with rectifier circuit 104, or with other rectifier circuits (204, ..., N04). When the switching circuits are connected in parallel, the current of each harmonic circuit is evenly distributed across different harmonic circuits, ensuring that the current value of the output electrical signal of each harmonic circuit is the same. When the switching circuits are connected in series, the voltage on each harmonic circuit is distributed across different harmonic circuits, ensuring that the voltage value across each transformer circuit is the same. Furthermore, the primary winding of each transformer T in each transformer circuit can be connected in series with the LC resonant circuit of the corresponding harmonic circuit.

[0060] In this application, in each harmonic circuit (100, 200, ..., N00), the number of LC resonant groups in the LC resonant circuit is the same as the input port P of the switching circuit, and the number of transformers in the transformer circuit is the same as the number of LC resonant groups in the LC resonant circuit.

[0061] In a transformer circuit, all transformers are generally identical, meaning they have the same impedance and the same number of turns in their primary and secondary windings. In one embodiment, for a single transformer, it is not limited to... Figure 2 The structure shown, that is, the ratio of the number of primary windings to secondary windings is 1:1, can also be 1:x, or x:1 or x:y, where x and y are positive integers greater than or equal to 1. This application does not limit this.

[0062] The rectifier circuit (104, 204, ..., N-4) is connected in series with the transformer circuit to convert the AC signal input from the transformer circuit into a DC signal. In one embodiment, combined with... Figure 2 As shown, the rectifier circuit 104 includes a first diode D. 11 Second diode D 12 Third diode D 13 Fourth diode D 14 Fifth diode D 15 and diode D 16 and output capacitor C 16 Among them, the first diode D 11 With the second diode D 12 Connected in series between them, and in the first diode D 11 With the second diode D 12 An input port P is electrically connected between them. 14 It can be electrically connected to the secondary winding of one or more transformers; the third diode D 13 and the fourth diode D 14 Connected in series between them, and in the third diode D 13 and the fourth diode D 14 An input port P is electrically connected between them. 15 It can be electrically connected to the secondary winding of one or more transformers; the fifth diode D 15 and diode D 16 Connected in series between them, and in the fifth diode D 15 and diode D 16 An input port P is electrically connected between them. 16 It can be electrically connected to the secondary winding of one or more transformers. Each set of diodes and output capacitor C 16 The diodes are connected in parallel. An AC signal is input to each group of diodes through three output ports P. The AC signal then flows out through either the upper or lower diode of each group, converting the AC signal into a DC signal, which is then passed through the input capacitor C. 11 Filtering is performed to obtain the filtered DC signal.

[0063] In this application, the rectifier circuits (104, 204, ..., N-4) can be connected in parallel to increase the current value of the output electrical signal by aggregating the current values ​​of the electrical signals from each rectifier circuit. The rectifier circuits of each harmonic circuit can also be connected in series to increase the voltage value of the output electrical signal by aggregating the voltage values ​​of the electrical signals from each rectifier circuit.

[0064] In this application, in each harmonic circuit (100, 200, ..., N00), the number of parallel diode groups in the rectifier circuit is the same as the input port P of the switching circuit, and the same as the number of transformers in the transformer circuit.

[0065] The LLC resonant converter circuit consists of multiple harmonic circuits. Multiple transformers within each harmonic circuit are electrically connected to each other and to a transformer in another harmonic circuit. This inter-circuiting allows the electrical signal from one harmonic circuit to be shunted or divided into another. Without adding any components, when the harmonic circuits are connected in parallel, the current value of each harmonic circuit is the same. Similarly, when the harmonic circuits are connected in series, the voltage value of each harmonic circuit is the same. This effectively reduces the complexity of the control strategy for the entire LLC resonant converter circuit and lowers its cost.

[0066] The technical solutions protected by this application will be introduced below based on different specific LLC resonant converter circuits.

[0067] Combination Figure 2 The illustrated two-channel three-phase LLC resonant converter circuit includes a first harmonic circuit 100 and a second harmonic circuit 200. The first harmonic circuit 100 includes a first switching circuit 101, a first LC resonant circuit 102, a first transformer circuit 103, and a first rectifier circuit 104. The second harmonic circuit 200 includes a second switching circuit 201, a second LC resonant circuit 202, a second transformer circuit 203, and a second rectifier circuit 204. The first switching circuit 101 and the second switching circuit 201 are connected in parallel, as are the first rectifier circuit 104 and the second rectifier circuit 204.

[0068] The first switching circuit 101 and the second switching circuit 201 are connected in parallel, and the voltage values ​​of the electrical signals input to the first harmonic circuit 100 and the second harmonic circuit 200 are the same. However, the current values ​​of the electrical signals flowing through the first harmonic circuit 100 and the second harmonic circuit 200 may be different, resulting in a difference in the resonant parameters between the electrical signals output by the first rectifier circuit 104 and the second rectifier circuit 204. Consequently, the electrical signals output by the two three-phase LLC resonant converter circuits cannot provide electrical signals to the electrical equipment.

[0069] In this application, to ensure that the current values ​​of the electrical signals flowing through the first harmonic circuit 100 and the second harmonic circuit 200 are the same, the primary windings of the two LC resonant circuits and the two transformer circuits can be cross-connected. The specific connection method is as follows:

[0070] The transformer T in the first transformer circuit 103 11 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 12 Series connection, transformer T 12 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 13 Series connection, transformer T 11 The other end is connected to transformer T 12 The other end is electrically connected to the transformer T of the second transformer circuit 203. 23 One end is electrically connected; transformer T 13 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 24 The other end is connected in series with the transformer T of the second transformer circuit 203. 21 One end and transformer T 22 One end is electrically connected. The transformer T in the second transformer circuit 203 is... 21 The other end is connected to the harmonic capacitor C of the second LC resonant circuit 202. 22 Series connection, transformer T 22 The other end is connected to the harmonic capacitor C of the second LC resonant circuit 202. 23 Series connection.

[0071] The connection method between the secondary windings of the two transformers in the two rectifier circuits and the two transformer circuits can be as follows:

[0072] The transformer T in the first transformer circuit 103 11 One end is connected to the input port P of the first rectifier circuit 104. 14 Series connection. Transformer T 12 One end is connected to the input port P of the first rectifier circuit 104. 15 Series connection. Transformer T 13 One end is connected to the input port P of the first rectifier circuit 104. 16 Series connection. Transformer T 11 The other end, transformer T 12 The other end and transformer T 13 The other end is electrically connected to each other. The transformer T in the second transformer circuit 203... 21 One end is connected to the input port P of the second rectifier circuit 204. 24 Series connection. Transformer T 22One end is connected to the input port P of the second rectifier circuit 204. 25 Series connection. Transformer T 23 One end is connected to the input port P of the second rectifier circuit 204. 26 Series connection. Transformer T 21 The other end, transformer T 22 The other end and transformer T 23 The other ends are electrically connected to each other. After the connection between the rectifier circuit and the secondary winding of the transformer is stretched, it forms a "Y" shape, which can be called a Y-type connection.

[0073] Transformer T 11 The current in the primary winding is I AT11 (Current values ​​are vector values, the same applies below), Transformer T 11 The current in the secondary winding is I BT11 Transformer T 12 The current in the primary winding is I AT12 Transformer T 12 The current in the secondary winding is I BT12 Transformer T 13 The current in the primary winding is I AT13 Transformer T 13 The current in the secondary winding is I BT13 Transformer T 21 The current in the primary winding is I AT21 Transformer T 21 The current in the secondary winding is I BT21 Transformer T 22 The current in the primary winding is I AT22 Transformer T 22 The current in the secondary winding is I BT22 Transformer T 23 The current in the primary winding is I AT23 Transformer T 23 The current in the secondary winding is I BT23 Among them, I AT11 I AT12 and I AT13 The phases between them are not the same, I AT11 and I BT11 The phases between them are the same; the relationships between other currents follow the same pattern. Optionally, I AT11 I AT12 and I AT13 The phase difference between them is 120°.

[0074] In the primary winding of the two transformer circuits, transformer T 11 With transformer T 12 They are electrically connected and connected to transformer T 23Electrical connection, so I AT11 +I AT12 =I AT23 Transformer T 21 With transformer T 22 They are electrically connected and connected to transformer T 13 Electrical connection, so I AT21 +I AT22 =I AT13 Among them, I AT11 I AT12 and I AT23 The phases between them are not the same, I AT21 I AT22 and I AT13 The phases between them are also different.

[0075] In the secondary windings of each transformer in the first transformer circuit 103, transformer T 11 Transformer T 12 and transformer T 13 Since they are electrically connected, the total current I1 of the first harmonic circuit 100 is I1 = I2. BT11 +I BT12 +I BT13 =n·I AT11 +n·I AT12 +n·I AT13 Where n represents the ratio between the number of turns in the primary winding and the number of turns in the secondary winding of the transformer.

[0076] Similarly, in the secondary windings of each transformer in the second transformer circuit 203, the total current I2 of the second harmonic circuit 200 is I2 = I3. BT21 +I BT22 +I BT223 =n·I AT21 +n·I AT22 +n·I AT23 In one embodiment, the primary and secondary windings of each transformer have the same number of turns, I1 = I2, and the current values ​​in the first harmonic circuit 100 and the second harmonic circuit 200 are the same, thereby achieving autonomous current sharing among the harmonic circuits in the two-way three-phase LLC resonant converter circuit.

[0077] In this embodiment, the two transformers of the first transformer circuit are electrically connected to each other, and then electrically connected to one transformer of the second transformer circuit, such that the current of the two transformers of the first transformer circuit is equal to the current of one transformer of the second transformer circuit.

[0078] Similarly, the two transformers in the second transformer circuit are electrically connected to each other, and then electrically connected to one transformer in the first transformer circuit, so that the current in the two transformers in the second transformer circuit is equal to the current in one transformer in the first transformer circuit, thereby making the current in the first transformer circuit equal to the current in the second transformer circuit, realizing the autonomous current sharing of each circuit in the two-way three-phase LLC resonant converter circuit.

[0079] For example, combined Figure 3 As shown, the connection method between the secondary windings of the two transformers in the two rectifier circuits and the two transformer circuits can also be:

[0080] The transformer T in the first transformer circuit 103 11 One end of the transformer T 12 One end and transformer T 13 One end of each component is electrically connected to the other. Transformer T 11 The other end is electrically connected to the input port P of the first rectifier circuit 104. 14 Up. Transformer T 12 The other end is electrically connected to the input port P of the first rectifier circuit 104. 15 Up. Transformer T 13 The other end is electrically connected to the input port P of the first rectifier circuit 104. 16 Above. Transformer T in the second transformer circuit 203. 21 One end of the transformer T 22 One end and transformer T 23 The two ends are connected in parallel. Transformer T 21 The other end is electrically connected to the input port P of the second rectifier circuit 204. 24 Up. Transformer T 22 The other end is electrically connected to the input port P of the second rectifier circuit 204. 25 Up. Transformer T 23 The other end is electrically connected to the input port P of the second rectifier circuit 204. 26 Above. When the connection between the LC resonant circuit and the transformer is stretched, it forms a "△" shape, which can be called a △ connection.

[0081] In the secondary windings of each transformer in the first transformer circuit 103, transformer T 11 Transformer T 12 and transformer T 13 Since they are electrically connected, the total current I1 of the first harmonic circuit 100 is I1 = I2. BT11 +I BT12 +I BT13 =n·I AT11 +n·I AT12 +n·I AT13 .

[0082] Similarly, in the secondary windings of each transformer in the second transformer circuit 203, the total current I2 of the second harmonic circuit 200 is I2 = I3. BT21 +I BT22 +I BT223 =n·I AT21 +n·I AT22 +n·I AT23 In one embodiment, the primary and secondary windings of each transformer have the same number of turns, I1 = I2, and the current value of each harmonic circuit is the same, which can realize the autonomous current sharing of each harmonic circuit in the two-way three-phase LLC resonant converter circuit.

[0083] In this embodiment of the application, the secondary windings of each transformer in the first transformer circuit 103 can be composed of multiple sub-windings. Combined with... Figure 4 As shown, the first harmonic circuit 100 also includes a first switch S1 and a second switch S2. Transformer T 11 Transformer T 12 and transformer T 13 The secondary windings are all composed of two sub-windings.

[0084] Transformer T 11 One end of the first sub-winding is connected to node P 14 Electrical connection, transformer T 11 The other end of the first sub-winding is electrically connected to the first interface 1 of the first switch S1. Transformer T 11 One end of the second sub-winding is electrically connected to the second interface 2 of the first switch S1, and the transformer T 11 The other end of the second sub-winding is connected to transformer T. 12 One end of the second sub-winding and transformer T 13 One end of the second sub-winding is electrically connected. Transformer T 12 One end of the first sub-winding is connected to node P 15 Electrical connection, transformer T 12 The other end of the first sub-winding is connected to transformer T 12 The other end of the second sub-winding is electrically connected. Transformer T 12 The other end of the second sub-winding, the third interface 3 of the first switch S1, and the third interface 3 of the second switch S2 are electrically connected to each other. Transformer T 13 One end of the first sub-winding is connected to node P 16 Electrical connection, transformer T 13 The other end of the first sub-winding is electrically connected to the first interface 1 of the second switch S2. Transformer T 13 One end of the second sub-winding is electrically connected to the second interface 2 of the second switch S1.

[0085] In one embodiment, when the first interface 1 of the first switch S1 is electrically connected to the second interface 2, and the first interface 1 of the second switch S2 is electrically connected to the second interface 2, the transformer T... 11 The first and second sub-windings are connected in series, and the transformer T 12 The first and second sub-windings are connected in series, and the transformer T 13 The first and second sub-windings are connected in series.

[0086] In one embodiment, when the first interface 1 of the first switch S1 is electrically connected to the third interface 3, and the first interface 1 of the second switch S2 is electrically connected to the third interface 3, the transformer T... 11 Transformer T 12 and transformer T 13 The first sub-winding of transformer T is in operation. 11 Transformer T 12 and transformer T 13 The second sub-winding is disconnected.

[0087] Similarly, the second harmonic circuit 200 also includes a third switch S3 and a fourth switch S4. Transformer T 21 Transformer T 22 and transformer T 23 The secondary windings are all composed of two sub-windings.

[0088] Transformer T 21 One end of the first sub-winding is connected to node P 24 Electrical connection, transformer T 21 The other end of the first sub-winding is electrically connected to the first interface 1 of the third switch S3. Transformer T 21 One end of the second sub-winding is electrically connected to the second interface 2 of the third switch S3, and the transformer T 21 The other end of the second sub-winding is connected to transformer T. 22 One end of the second sub-winding and transformer T 23 One end of the second sub-winding is electrically connected. Transformer T 22 One end of the first sub-winding is connected to node P 25 Electrical connection, transformer T 22 The other end of the first sub-winding is connected to transformer T 22 The other end of the second sub-winding is electrically connected. Transformer T 22 The other end of the second sub-winding, the third interface 3 of the third switch S3, and the third interface 3 of the fourth switch S4 are electrically connected to each other. Transformer T 23 One end of the first sub-winding is connected to node P 26 Electrical connection, transformer T 23 The other end of the first sub-winding is electrically connected to the first interface 1 of the fourth switch S4. Transformer T23 One end of the second sub-winding is electrically connected to the second interface 2 of the fourth switch S4.

[0089] In one embodiment, when the first interface 1 of the third switch S3 is electrically connected to the second interface 2, and the first interface 1 of the fourth switch S4 is electrically connected to the second interface 2, the transformer T... 21 The first and second sub-windings are connected in series, and the transformer T 22 The first and second sub-windings are connected in series, and the transformer T 23 The first sub-winding and the second sub-winding are connected in series.

[0090] In one embodiment, when the first interface 1 of the first switch S3 is electrically connected to the third interface 3, and the first interface 1 of the second switch S4 is electrically connected to the third interface 3, the transformer T... 21 Transformer T 22 and transformer T 23 The first sub-winding of transformer T is in operation. 21 Transformer T 22 and transformer T 23 The second sub-winding is disconnected.

[0091] In this embodiment, a control circuit 301 is provided between the first harmonic circuit 100 and the second harmonic circuit 200. The four contacts of the control circuit 301 are electrically connected to the positive terminal, negative terminal, positive terminal, and negative terminal of the first harmonic circuit 100, respectively. In one embodiment, when the control circuit 301 is in a first state, the negative terminal of the first harmonic circuit 100 and the positive terminal of the second harmonic circuit 200 are electrically connected. At this time, the output terminals of the first harmonic circuit 100 and the second harmonic circuit 200 are connected in series, realizing a wide range of output voltage from the LLC resonant converter circuit.

[0092] In one embodiment, when the control circuit 301 is in the second state, the positive terminals of the first harmonic circuit 100 and the second harmonic circuit 200 are electrically connected, and the negative terminals of the first harmonic circuit 100 and the second harmonic circuit 200 are electrically connected. At this time, the output terminals of the first harmonic circuit 100 and the second harmonic circuit 200 are connected in parallel, achieving voltage and current equalization at the output of the LLC resonant converter circuit. Furthermore, the LLC resonant converter circuit can provide high-current charging, enabling devices equipped with this LLC resonant converter circuit to have fast charging and supercharging capabilities.

[0093] Combination Figure 5 As shown, in order to make the current values ​​of the electrical signals flowing through the first harmonic circuit 100 and the second harmonic circuit 200 the same, the secondary windings of the transformers in the two rectifier circuits and the two transformer circuits can be cross-connected. The specific connection method is as follows:

[0094] The transformer T in the first transformer circuit 103 11 One end is electrically connected to the input port P of the first rectifier circuit 104. 14 Up. Transformer T 12 One end is electrically connected to the input port P of the first rectifier circuit 104. 15 Up. Transformer T 11 The other end is connected to transformer T 12 The other end is electrically connected to the transformer T of the second transformer circuit 203. 23 One end is electrically connected. Transformer T 13 One end is electrically connected to the input port P of the second rectifier circuit 204. 26 The other end is connected to the transformer T of the second transformer circuit 203. 21 One end and transformer T 22 One end is electrically connected. The transformer T in the second transformer circuit 203 is... 21 The other end is electrically connected to the input port P of the second rectifier circuit 204. 24 Up. Transformer T 22 The other end is electrically connected to the input port P of the second rectifier circuit 204. 25 superior.

[0095] The connection between the primary windings of the two transformers in the two rectifier circuits and two transformer circuits can be a Y-type connection, specifically as follows:

[0096] The transformer T in the first transformer circuit 103 11 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 12 Series connection. Transformer T 12 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 13 Series connection. Transformer T 13 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 14 Series connection. Transformer T 11 The other end, transformer T 12 The other end and transformer T 13 The other end is electrically connected to each other. The transformer T in the second transformer circuit 203... 21 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 22 Series connection. Transformer T 22 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 23 Series connection. Transformer T 23 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 24 Series connection. Transformer T21 The other end, transformer T 22 The other end and transformer T 23 The other end is electrically connected to each other.

[0097] In the secondary windings of two transformer circuits, transformer T 11 With transformer T 12 They are electrically connected and connected to transformer T 23 Electrical connection, so I BT11 +I BT12 =I BT23 Transformer T 21 With transformer T 22 They are electrically connected and connected to transformer T 13 Electrical connection, so I BT21 +I BT22 =I BT13 Because the total current I1 of the first harmonic circuit 100 is I... BT11 +I BT12 +I BT13 The total current I2 of the second harmonic circuit 200 is I2 = I BT21 +I BT22 +I BT223 Therefore, I1 = I2, and the current value of each harmonic circuit is the same, which can realize the autonomous current sharing of each harmonic circuit in the two-way three-phase LLC resonant converter circuit. Where I... BT11 I BT12 and I BT23 The phases between them are not the same, I BT21 I BT22 and I BT13 The phases between them are also different.

[0098] In this application, Figure 5 The connection method between the rectifier circuit and the secondary winding of the transformer is exemplified by a Y-type connection, but a delta-type connection is also possible; this application does not limit the specific connection method. For details on the connection structure, please refer to [reference needed]. Figure 3 and Figure 3 The corresponding technical solutions will not be elaborated here.

[0099] Combination Figure 6 The N-channel three-phase LLC resonant converter circuit shown includes N harmonic circuits (100, 200, ..., N00), where N is a positive even number greater than 2. To ensure that the current values ​​flowing through the first harmonic circuit 100 and the second harmonic circuit 200 are the same, the two LC resonant circuits can be cross-connected to the primary windings of the transformers in the two transformer circuits. The specific connection method is as follows:

[0100] The transformer T in the first transformer circuit 103 11One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 12 Series connection. Transformer T 12 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 13 Series connection. Transformer T 11 The other end is connected to transformer T 12 The other end is electrically connected to each other, and sequentially connected to the transformer T of the second transformer circuit 203. 23 One end, ..., the transformer T of the Nth transformer circuit N03 N3 One end is electrically connected, so that each harmonic circuit includes a current I. BT11 +I BT12 The transformer T in the first transformer circuit 103 13 The two ends are respectively connected to the transformer T of the second transformer circuit 203. 21 and transformer T 22 After mutual electrical connection of nodes, ..., transformer T of the Nth transformer circuit N03 N1 and transformer T N2 The interconnected nodes ensure that each harmonic circuit includes a current I. BT21 +I BT22 +…+I BTN1 +I BTN2 The current in each harmonic circuit is I = I BT11 +I BT12 +I BT21 +I BT22 +…+I BTN1 +I BTN2 Each harmonic circuit has the same current value, enabling autonomous current sharing among all harmonic circuits in an N-channel three-phase LLC resonant converter circuit.

[0101] In this application, Figure 6 The connection method between the rectifier circuit and the secondary winding of the transformer is exemplified by a Y-type connection, but a delta-type connection is also possible. This application does not limit the specific connection method; however, the specific connection structure can be found in [reference needed]. Figure 3 and Figure 3 The corresponding technical solutions will not be elaborated here.

[0102] In this application, Figure 6 Taking the cross-connection method between the primary windings of each transformer in the LC resonant circuit and the transformer circuit as an example, this achieves the same current value for the electrical signal flowing through each harmonic circuit. It can also be achieved by cross-connecting between the secondary windings of each transformer in the rectifier circuit and the transformer circuit; this application does not limit this approach. For specific connection structures, please refer to... Figure 5 and Figure 5 The corresponding technical solutions will not be elaborated here.

[0103] It should be noted that the embodiments provided in this application... Figures 1-3 and Figure 6 ,as well as Figures 1-3 and Figure 6 In the corresponding scheme, the rectifier circuits (104, 204, ..., N-4) are all electrically connected in parallel to increase the current value of the output electrical signal. Clearly, this application... Figures 1-9 In the corresponding scheme, the rectifier circuits (104, 204, ..., N-4) can also be connected in series to increase the voltage value of the output electrical signal.

[0104] However, for Figure 5 In this scheme, the cross-connection between each rectifier circuit and the secondary winding of each transformer achieves the effect of autonomous current sharing among the harmonic circuits. In one embodiment, when the rectifier circuits are connected in series, the transformers and rectifier circuits are at the same potential. However, the cross-connection between the rectifier circuits and the secondary windings of each transformer does not achieve the effect of autonomous current sharing among the harmonic circuits. Therefore, for... Figure 5 In this scheme, the rectifier circuits cannot be electrically connected in series.

[0105] Combination Figure 7 The illustrated two-channel three-phase LLC resonant converter circuit includes a first harmonic circuit 100 and a second harmonic circuit 200. The first harmonic circuit 100 includes a first switching circuit 101, a first LC resonant circuit 102, a first transformer circuit 103, and a first rectifier circuit 104. The second harmonic circuit 200 includes a second switching circuit 201, a second LC resonant circuit 202, a second transformer circuit 203, and a second rectifier circuit 204. The first switching circuit 101 and the second switching circuit 201 are connected in series, and the first rectifier circuit 104 and the second rectifier circuit 204 are connected in parallel.

[0106] In one embodiment, the first switching circuit 101 and the second switching circuit 201 are connected in series, and the current values ​​of the electrical signals flowing through the first harmonic circuit 100 and the second harmonic circuit 200 are the same. However, the voltage values ​​of the electrical signals of the first harmonic circuit 100 and the second harmonic circuit 200 may be different, resulting in a difference in the resonant parameters between the electrical signals output by the first rectifier circuit 104 and the second rectifier circuit 204. This causes the electrical signals output by the two three-phase LLC resonant converter circuits to be unable to provide electrical signals to the electrical equipment.

[0107] In this application, to ensure that the voltage values ​​of the electrical signals flowing through the first harmonic circuit 100 and the second harmonic circuit 200 are the same, the secondary windings of the transformers in the two rectifier circuits and the two transformer circuits can be cross-connected. The specific connection method is as follows:

[0108] The transformer T in the first transformer circuit 103 11 One end is electrically connected to the input port P of the first rectifier circuit 104. 14 Up. Transformer T 12 One end is electrically connected to the input port P of the first rectifier circuit 104. 15 Up. Transformer T 11 The other end and transformer T 12 The other end is electrically connected to the transformer T of the second transformer circuit 203. 21 One end is electrically connected. Transformer T 13 One end is electrically connected to the input port P of the second rectifier circuit 204. 24 superior.

[0109] The transformer T in the second transformer circuit 203 21 The other end is electrically connected to the input port P of the first rectifier circuit 104. 16 Up. Transformer T 22 One end is electrically connected to the input port P of the second rectifier circuit 204. 25 Up. Transformer T 23 One end is electrically connected to the output port P of the second rectifier circuit 204. 23 Up. Transformer T 22 The other end and transformer T 23 The other end is electrically connected to the transformer T of the first transformer circuit 103. 13 The other end is electrically connected.

[0110] The connection between the primary windings of the two transformers in the two rectifier circuits and two transformer circuits can be a Y-type connection, specifically as follows:

[0111] The transformer T in the first transformer circuit 103 11 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 12 Series connection. Transformer T 12 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 13 Series connection. Transformer T 13 One end is connected to the harmonic capacitor C of the first LC resonant circuit 102 14 Series connection. Transformer T 11 The other end, transformer T 12 The other end and transformer T 13The other end is electrically connected to each other. The transformer T in the second transformer circuit 203... 21 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 22 Series connection. Transformer T 22 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 23 Series connection. Transformer T 23 One end is connected to the harmonic capacitor C of the second LC resonant circuit 202 24 Series connection. Transformer T 21 The other end, transformer T 22 The other end and transformer T 23 The other end is electrically connected to each other.

[0112] Transformer T 11 The voltage of the primary winding is V AT11 Transformer T 11 The voltage of the secondary winding is V BT11 Transformer T 12 The voltage of the primary winding is V AT12 Transformer T 12 The voltage of the secondary winding is V BT12 Transformer T 13 The voltage of the primary winding is V AT13 Transformer T 13 The voltage of the secondary winding is V BT13 Transformer T 21 The voltage of the primary winding is V AT21 Transformer T 21 The voltage of the secondary winding is V BT21 Transformer T 22 The voltage of the primary winding is V AT22 Transformer T 22 The voltage of the secondary winding is V BT22 Transformer T 23 The voltage of the primary winding is V AT23 Transformer T 23 The voltage of the secondary winding is V BT23 Among them, V AT11 V AT12 and V AT13 The phases between them are not the same, V AT11 and V BT11 The phases between them are the same; the relationships between other currents follow the same pattern. Optionally, V AT11 V AT12 and V AT13 The phase difference between them is 120°.

[0113] In the secondary windings of two transformer circuits, transformer T 11 The other end, transformer T12 The other end and transformer T 13 The other ends are electrically connected to each other, V AT11 =V AT12 =V AT13 Similarly, transformer T 21 The other end, transformer T 22 The other end and transformer T 23 The other ends are electrically connected to each other, V AT21 =V AT22 =V AT23 And V AT11 =n·V BT11 V AT12 =n·V BT12 V AT13 =n·V BT13 V AT21 =n·V BT21 V AT22 =n·V BT22 V AT23 =n·V BT23 In one embodiment, the primary and secondary windings of each transformer have the same number of turns, then V BT11 =V BT12 =V BT13 =V B1 V BT21 =V BT22 =V BT23 =V B2 .

[0114] Transformer T 11 With transformer T 12 They are electrically connected and connected to transformer T 21 Electrical connection. Output voltage of the first harmonic circuit 104. Similarly, transformer T 22 With transformer T 23 They are electrically connected and connected to transformer T 13 Electrical connection, therefore the output voltage of the second harmonic circuit 204 The voltage value V1 of the first harmonic circuit 100 is the same as the voltage value V2 of the second harmonic circuit 200, thereby achieving autonomous voltage equalization of each harmonic circuit in the two-way three-phase LLC resonant converter circuit.

[0115] Combination Figure 8 As shown, the N-channel three-phase LLC resonant converter circuit includes N harmonic circuits (100, 200, ..., N00). N is a positive even number greater than 2. To ensure that the voltage values ​​of the electrical signals flowing through the first harmonic circuit 100 and the second harmonic circuit 200 are the same, the secondary windings of the transformers in the two rectifier circuits and the two transformer circuits can be cross-connected. The specific connection method is as follows:

[0116] The transformer T in the first transformer circuit 103 11 One end is electrically connected to the input port P of the first rectifier circuit 104. 14 Up. Transformer T 12 One end is electrically connected to the input port P of the first rectifier circuit 104. 15 Up. Transformer T 11 The other end is connected to transformer T 12 The other end is electrically connected to each other, and sequentially connected to the transformer T of the second transformer circuit 203. 21 One end, ..., the transformer T of the Nth transformer circuit N03 N1 One end is electrically connected, making the voltage in the first harmonic circuit 100 be The transformer T in the second transformer circuit 203 22 One end is electrically connected to the input port P of the second rectifier circuit 204. 25 Up. Transformer T 23 One end is electrically connected to the input port P of the second rectifier circuit 204. 26 Up. Transformer T 22 The other end is connected to transformer T 23 The other end is electrically connected to each other, and sequentially connected to the transformer T of the first transformer circuit 103. 13 One end, ..., the transformer T of the Nth transformer circuit N03 N3 One end is electrically connected, making the voltage in the second harmonic circuit 100 be Following this logic, we can obtain V1 = V2 = ... = V N Each harmonic circuit has the same voltage value, which enables autonomous voltage equalization of each harmonic circuit in an N-channel three-phase LLC resonant converter circuit.

[0117] Combination Figure 9 As shown, the N-channel three-phase LLC resonant converter circuit includes N / 2 such... Figure 4The diagram shows a two-way three-phase LLC resonant converter circuit. N is a positive even number greater than 2. The input terminals of each two-way three-phase LLC resonant converter circuit are connected in series, allowing 2N three-phase LLC resonant converter circuits to be connected to a high-voltage circuit to meet high-voltage input requirements. The output terminals of each two-way three-phase LLC resonant converter circuit can be connected in parallel, enabling automatic voltage equalization at the input series terminals. With the input terminals of each two-way three-phase LLC resonant converter circuit connected in parallel, the voltage across the primary windings of each transformer is consistent, enabling automatic voltage equalization when the output terminals of each two-way three-phase LLC resonant converter circuit are connected in series. The primary windings of each transformer in the first transformer circuit 103 of the first harmonic circuit 100 of each two-way three-phase LLC resonant converter circuit are cross-connected with the primary windings of each transformer in the second transformer circuit 203 of the second harmonic circuit 200, forming a Y-type connection. The Y-type connected transformers have neutral point voltage regulation capability, and each harmonic circuit can achieve automatic current sharing, ensuring balanced output power at the output terminals of each harmonic circuit and reducing output current ripple.

[0118] In this application, Figure 7 and Figure 9 The connection method between the LC resonant circuit and the primary winding of the transformer is exemplified by a Y-type connection, but a delta-type connection is also possible. This application does not limit the specific connection method; however, the specific connection structure can be found in [reference needed]. Figure 3 and Figure 3 The corresponding technical solutions will not be elaborated here.

[0119] This application provides a charging device, which includes an LLC resonant converter circuit, wherein the LLC resonant converter circuit can be as follows: Figures 1-9 The charging device includes the LLC resonant converter circuit described in the corresponding protection scheme above, and therefore possesses all or at least some of the advantages of the LLC resonant converter circuit. This charging device can be a charging station, charger, or similar equipment.

[0120] This application provides an energy storage device, which includes an LLC resonant converter circuit and a battery. The LLC resonant converter circuit is electrically connected to the battery and processes electrical signals input into the battery before inputting those signals back into the battery. The LLC resonant converter circuit can be, for example,... Figures 1-9 The energy storage device includes the LLC resonant converter circuit described in the corresponding protection scheme above, and therefore possesses all or at least some of the advantages of the LLC resonant converter circuit. The energy storage device can be a lithium battery, a storage battery, etc.

[0121] This application provides an electrical device including an LLC resonant converter circuit and at least one electrical component. The LLC resonant converter circuit, connected to the at least one electrical component, processes electrical signals input to the at least one electrical component and then inputs these signals back into the at least one electrical component. The LLC resonant converter circuit can be, for example,... Figures 1-9 The LLC resonant converter circuit described in the corresponding protection scheme above, since the electrical equipment includes the LLC resonant converter circuit, therefore the electrical equipment package has all or at least some of the advantages of the LLC resonant converter circuit. The electrical equipment can be an electric vehicle, a base station, a communication device, etc.

[0122] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions in the embodiments of this application.

Claims

1. An LLC resonant converter circuit, characterized in that, include: There are N harmonic circuits, where N is a positive integer greater than or equal to 2; Each harmonic circuit includes a switching circuit, an LC resonant circuit, a transformer circuit, and a rectifier circuit connected in sequence; the transformer circuit includes at least three transformers, each transformer including a first winding and a second winding, the first winding being the primary winding and the second winding being the secondary winding; In this circuit, at least two transformers of the transformer circuit of the first harmonic circuit have one end of their first winding electrically connected to the LC resonant circuit of the first harmonic circuit, and the other end electrically connected to each other and electrically connected to one end of the first winding of a transformer of another harmonic circuit. The other harmonic circuits are those other than the first harmonic circuit among the N harmonic circuits; or One end of the second winding of at least two transformers in the transformer circuit of the first harmonic circuit is electrically connected to the rectifier circuit of the first harmonic circuit, and the other end is electrically connected to each other and electrically connected to one end of the second winding of one transformer in the transformer circuit of the other harmonic circuit.

2. The circuit according to claim 1, characterized in that, When the switching circuits of each harmonic circuit are connected in parallel, In the first transformer circuit, one end of the first winding of at least two transformers is electrically connected to the first LC resonant circuit, and the other ends of the first windings of the at least two transformers are electrically connected to each other and electrically connected to one end of the first winding of the first transformer in the second transformer circuit; the other end of the first winding of the first transformer is electrically connected to the first LC resonant circuit. One end of the first winding of at least two transformers other than the first transformer in the second transformer circuit is electrically connected to the second LC resonant circuit. The other ends of the first windings of the at least two transformers other than the first transformer in the second transformer circuit are electrically connected to each other and electrically connected to one end of the first winding of the second transformer in the first transformer circuit. The other end of the first winding of the second transformer is electrically connected to the second LC resonant circuit. The first harmonic circuit includes the first LC resonant circuit and the first transformer circuit. The second transformer is one of the transformers in the first transformer circuit other than the at least two transformers. The other harmonic circuits include the second harmonic circuit, which includes the second LC resonant circuit and the second transformer circuit.

3. The circuit according to claim 2, characterized in that, In the first transformer circuit, one end of the second winding of at least three transformers is electrically connected to the first rectifier circuit, and the other ends of the second windings of the at least three transformers are electrically connected to each other; in the second transformer circuit, one end of the second winding of at least three transformers is electrically connected to the second rectifier circuit, and the other ends of the second windings of the at least three transformers are electrically connected to each other; wherein, the first harmonic circuit includes the first rectifier circuit, and the second harmonic circuit includes the second rectifier circuit.

4. The circuit according to any one of claims 1-3, characterized in that, The rectifier circuits of each harmonic circuit are connected in series or in parallel.

5. The circuit according to claim 1, characterized in that, When the switching circuits of each harmonic circuit are connected in series or in parallel, In the first transformer circuit, one end of the second winding of at least two transformers is electrically connected to the first rectifier circuit, and the other ends of the second windings of the at least two transformers are electrically connected to each other and electrically connected to one end of the second winding of the first transformer in the second transformer circuit; the other end of the second winding of the first transformer is electrically connected to the first rectifier circuit. One end of the second winding of at least two transformers other than the first transformer in the second transformer circuit is electrically connected to the second rectifier circuit. The other ends of the second windings of the at least two transformers other than the first transformer in the second transformer circuit are electrically connected to each other and electrically connected to one end of the second winding of the second transformer in the first transformer circuit. The other end of the second winding of the second transformer is electrically connected to the second rectifier circuit. The first harmonic circuit includes the first transformer circuit and the first rectifier circuit. The second transformer is one of the transformers in the first transformer circuit other than the at least two transformers. The other harmonic circuits include the second harmonic circuit, which includes the second transformer circuit and the second rectifier circuit.

6. The circuit according to claim 5, characterized in that, In the first transformer circuit, one end of the first winding of at least three transformers is electrically connected to the first LC resonant circuit, and the other ends of the first windings of the at least three transformers are electrically connected to each other; in the second transformer circuit, one end of the first winding of at least three transformers is electrically connected to the second LC resonant circuit, and the other ends of the first windings of the at least three transformers are electrically connected to each other; wherein, the first harmonic circuit includes the first LC resonant circuit, and the second harmonic circuit includes the second LC resonant circuit.

7. The circuit according to claim 5 or 6, characterized in that, The rectifier circuits of each harmonic circuit are connected in parallel.

8. The circuit according to any one of claims 1-3, characterized in that, Each transformer in each transformer circuit is identical.

9. The circuit according to any one of claims 1-3, characterized in that, The at least three transformers in each transformer circuit share a single iron core.

10. The circuit according to any one of claims 1-3, characterized in that, The second winding of each transformer circuit includes multiple sub-windings.

11. The circuit according to claim 10, characterized in that, Each second winding of each transformer circuit includes at least a first sub-winding and a second sub-winding, and each transformer circuit also includes at least two switches. The at least two switches are used, when in the first state, to connect the first sub-winding of each second winding of each transformer circuit in series with the second sub-winding of each second winding of the transformer circuit. And when in the second state, the second sub-winding of each second winding of each transformer circuit is disconnected.

12. The circuit according to claim 11, characterized in that, Each transformer circuit includes a first transformer, a second transformer, and a third transformer. The at least two switches include a first switch and a second switch. Both the first switch and the second switch include three nodes. Each second winding of each transformer circuit includes a first sub-winding and a second sub-winding. One end of the first sub-winding of the first transformer is electrically connected to the rectifier circuit of the harmonic circuit; the other end of the first sub-winding of the first transformer is electrically connected to the first interface of the first switch; one end of the second sub-winding of the first transformer is electrically connected to the second interface of the first switch; the other end of the second sub-winding of the first transformer is electrically connected to one end of the second sub-winding of the second transformer and one end of the second sub-winding of the third transformer, respectively. One end of the first sub-winding of the second transformer is electrically connected to the rectifier circuit of the harmonic circuit; the other end of the first sub-winding of the second transformer is electrically connected to the other end of the second sub-winding of the second transformer; the other end of the second sub-winding of the second transformer, the third interface of the first switch, and the third interface of the second switch are electrically connected to each other. One end of the first sub-winding of the third transformer is electrically connected to the rectifier circuit of the harmonic circuit; the other end of the first sub-winding of the third transformer is electrically connected to the first interface of the second switch; and one end of the second sub-winding of the third transformer is electrically connected to the second interface of the second switch.

13. The circuit according to claim 10, characterized in that, The number of turns in the multiple sub-windings of the second winding of each transformer circuit is the same.

14. The circuit according to claim 10, characterized in that, Also includes: A control circuit, electrically connected between two rectifier circuits, is used to connect the output terminals of the two rectifier circuits in parallel when in the first state; And when in the second state, the output terminals of the two rectifier circuits are connected in series.

15. A charging device, characterized in that, include: At least one LLC resonant converter circuit as described in any one of claims 1-14.

16. An energy storage device, characterized in that, include: Battery; At least one LLC resonant converter circuit as described in any one of claims 1-14, wherein the LLC resonant converter circuit is electrically connected to the battery for processing electrical signals input into the battery and inputting them into the battery.

17. An electrical appliance, characterized in that, include: At least one electrical component; At least one LLC resonant converter circuit as described in any one of claims 1-14, wherein the at least one LLC resonant converter circuit is electrically connected to the at least one electrical device for processing electrical signals input to the at least one electrical device and inputting them into the at least one electrical device.

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