Direct current conversion circuit, charging module and charging pile

Abstract

The utility model provides a direct current conversion circuit, a charging module and a charging pile, and relates to the field of power modules. The DC conversion circuit comprises a voltage transformation module, N output branches and a high-frequency capacitor, wherein N is an integer greater than or equal to 2; the voltage transformation module is provided with N groups of positive and negative output ends, the N groups of positive and negative output ends are respectively connected with positive and negative input ends of N output branches, and the positive and negative output ends of the N output branches are used for outputting direct-current voltage; and a high-frequency capacitor is connected between dotted terminals of a secondary coil of the voltage transformation module. Therefore, under the condition that the output is connected with light load or no load, the high-frequency capacitor is connected between the dotted terminals of the secondary side coil of the voltage transformation module, voltage and current sharing of the direct current conversion circuit is achieved, energy transfer of the direct current conversion circuit is achieved, and the direct current conversion circuit is low in cost and high in reliability.

Description

Technical Field

[0001] The present application relates to the field of power modules, and more specifically, to a DC conversion circuit, a charging module and a charging pile. Background Art

[0002] With the rapid development of power electronics technology, higher and higher requirements are placed on DC conversion circuits with the same switch output in electric vehicles or charging piles, so as to achieve voltage and current equalization effects through DC conversion circuits.

[0003] In the prior art, in a DC conversion circuit with the same switch output, in order to achieve equal current and voltage at the output of the DC conversion circuit, a dummy load is connected in parallel to each output branch to generate a load current to offset the bias problem caused by uneven current in the DC conversion circuit due to slightly asymmetric parameters.

[0004] However, if the output of the DC conversion circuit is connected to a light load or no load, due to the large differences in parameters such as the power circuit and individual transformers, it will be difficult to achieve the effect of equalizing current and voltage at the output of the DC conversion circuit in the prior art, and it will be costly and large in size. Utility Model Content

[0005] The purpose of the present application is to provide a DC conversion circuit, a charging module and a charging pile, which can achieve voltage and current balancing of the DC conversion circuit when the output is light load or no load, and have low cost and high reliability.

[0006] To achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

[0007] In a first aspect, an embodiment of the present application provides a DC conversion circuit, the DC conversion circuit comprising: a voltage conversion module, N output branches and a high-frequency capacitor, where N is an integer greater than or equal to 2;

[0008] The transformer module has N groups of positive and negative output terminals, the N groups of positive and negative output terminals are respectively connected to the positive and negative input terminals of the N output branches, and the positive and negative output terminals of the N output branches are used to output a DC voltage;

[0009] The high-frequency capacitor is connected between the same-name ends of the secondary coil of the transformer module.

[0010] Optionally, the transformer module comprises: at least two transformers, the positive and negative output ends of the secondary coils of the at least two transformers are respectively the N groups of positive and negative output ends;

[0011] The high-frequency capacitor is connected between the same-name end of the secondary coil of the first transformer and the same-name end of the secondary coil of the second transformer.

[0012] Optionally, the high-frequency capacitor is connected between the positive same-name end of the secondary coil of the first transformer and the positive same-name end of the secondary coil of the second transformer;

[0013] And / or, the high-frequency capacitor is connected between the negative same-name end of the secondary coil of the first transformer and the negative same-name end of the secondary coil of the second transformer.

[0014] Optionally, the transformer module comprises: at least two groups of transformer units, each group of transformer units comprises: a first sub-transformation unit and a second sub-transformation unit;

[0015] The positive and negative output ends of the secondary coils of the first sub-transformer units in the at least two groups of transformer units, which are connected in series in sequence, are the first group of positive and negative output ends; the positive and negative output ends of the secondary coils of the second sub-transformer units in the at least two groups of transformer units, which are connected in series in sequence, are the second group of positive and negative output ends;

[0016] The high-frequency capacitor is connected between the same-name ends of the secondary coils of the first sub-transformation unit and the second sub-transformation unit.

[0017] Optionally, the high-frequency capacitor is connected between the positive same-name ends of the secondary coils of the first sub-transformation unit and the second sub-transformation unit in the first transformation unit in the specified transformation unit;

[0018] And / or, the high-frequency capacitor is connected between negative same-name ends of the secondary coils of the first sub-transformation unit and the second sub-transformation unit in the second transformation unit in the designated transformation unit.

[0019] Optionally, the high-frequency capacitor is connected between a first series connection point of the secondary coil of the first sub-transformer unit in the designated transformer unit and a second series connection point of the second sub-transformer unit.

[0020] Optionally, each output branch includes: a rectifier unit and a capacitor unit; wherein the input end of the rectifier unit is the positive and negative input end of each output branch, which is used to connect a group of positive and negative output ends of the transformer module;

[0021] The output end of the rectifier unit is connected to the two ends of the capacitor unit; the two ends of the capacitor unit are the positive and negative output ends of each output branch.

[0022] Optionally, the N output branches further include: N-1 first switch units, N-1 second switch units and N-1 third switch units;

[0023] One end of the capacitor unit in the first output branch of two adjacent output branches is connected to one end of the capacitor unit in the second output branch of the two adjacent output branches through a first switching unit, the other end of the capacitor unit in the first output branch is connected to the other end of the capacitor unit in the second output branch through a second switching unit, and the other end of the capacitor unit in the first output branch is connected to one end of the capacitor unit in the second output branch through a third switching unit.

[0024] In a second aspect, an embodiment of the present application provides a charging module, comprising: a DC conversion circuit as described in any one of the first aspects, and a rectifier circuit; wherein the rectifier circuit is connected to a preset AC power supply and an input end of the DC conversion circuit; and the rectifier circuit is used to convert the AC voltage output by the preset AC power supply into a DC voltage.

[0025] In a third aspect, an embodiment of the present application provides a charging pile, comprising: at least one charging module as described in the second aspect and a control module, wherein the control module is connected to the charging module, and the control module is used to control the charging module to charge an object to be charged.

[0026] The beneficial effects of the DC conversion circuit provided by the present application are:

[0027] An embodiment of the present application provides a DC conversion circuit, which includes: a transformer module, N output branches and a high-frequency capacitor, where N is an integer greater than or equal to 2; the transformer module has N groups of positive and negative output terminals, the N groups of positive and negative output terminals are respectively connected to the positive and negative input terminals of the N output branches, and the positive and negative output terminals of the N output branches are used to output DC voltage; a high-frequency capacitor is connected between the same-name ends of the secondary coil of the transformer module. Therefore, the present application can connect the like-named ends of the transformer module by short-circuiting the high-frequency capacitor between the like-named ends of the transformer module, so that when the DC conversion circuit is unloaded or lightly loaded, the high-energy side is transferred to the low-energy side through the high-frequency capacitor, so that the energy between the like-named ends of the transformer module can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current in the DC conversion circuit; at the same time, since the DC conversion circuit in the present application only adds one high-frequency capacitor, the effect of equalizing current and voltage in the DC conversion circuit can be achieved, so that the structure of the DC conversion circuit is simple and the cost is low, and the high-frequency capacitor has a long life and a small size, thereby improving the reliability of the DC conversion circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 1 ;

[0030] Figure 2 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 2 ;

[0031] Figure 3 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 3 ;

[0032] Figure 4 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 4 ;

[0033] Figure 5 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 5 ;

[0034] Figure 6 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 6 ;

[0035] Figure 7 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 7 ;

[0036] Figure 8 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 8 ;

[0037] Fig. 9 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 9 ;

[0038] Fig.10 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 ;

[0039] Fig.11 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 one;

[0040] Fig.12 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 two;

[0041] Fig.13 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 three;

[0042] Fig.14 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 Four;

[0043] Fig.15 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 five;

[0044] Fig.16 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 six;

[0045] Fig.17 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 seven;

[0046] Fig.18 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 eight;

[0047] Fig.19 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 1 ;

[0048] Fig. 20 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 2 ;

[0049] Fig.21 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 3 ;

[0050] Fig. 22 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 4 ;

[0051] Fig.23 A schematic diagram of the structure of a charging module provided in an embodiment of the present application;

[0052] Fig.24 A schematic diagram of the structure of a charging pile provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0055] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0056] In the description of the present application, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0057] Furthermore, the terms “first”, “second”, “third”, etc. are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0058] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two groups of components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0060] A DC conversion circuit provided in an embodiment of the present application is described in detail below in conjunction with the accompanying drawings.

[0061] Figure 1 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 1 .like Figure 1 As shown, the DC conversion circuit 100 may include: a transformer module 110 , N output branches 120 and a high-frequency capacitor 130 .

[0062] Wherein, N is an integer greater than or equal to 2.

[0063] The transformer module 110 has N groups of positive and negative output terminals, which are respectively connected to the positive and negative input terminals of the N output branches 120, and the positive and negative output terminals of the N output branches 120 are used to output a DC voltage, so as to output the output electrical signal of the transformer module 110 through the N output branches 120; the high-frequency capacitor 130 is connected between the same-named ends of the secondary coil of the transformer module 110 to pull through the transformer module 110, so that the transformer module 110 can transfer part of the energy through the high-frequency capacitor 130 when the current is small, such as no-load or light-load, so as to achieve the transfer of high energy to the low-energy side, thereby achieving the effect of equalizing the voltage or current of the output of the N output branches 120. The same-named ends of the secondary coil of the transformer module 110 can be selected according to actual conditions, for example, the same-named ends of the secondary coil of the transformer module 110 can be positive or negative.

[0064] It should be noted that, since the output voltage waveforms between the windings of the same-name end of the secondary coil of the transformer module 110 are basically the same, there is no obvious voltage difference, therefore, the high-frequency capacitor 130 is connected between the same-name ends of the secondary coil of the transformer module 110, so that the same-name ends of the secondary coil of the transformer module 110 are connected in parallel through the high-frequency capacitor 130, and then the same-name ends of the secondary coil of the transformer module 110 are connected through the high-frequency capacitor 130, so that the larger current can be appropriately shunted to the branch with smaller current through the high-frequency capacitor 130, so as to achieve the transfer of high energy to the low-energy side, thereby alleviating the bias of the DC conversion circuit 100. At the same time, since the output voltage waveforms and phases between the windings of the same-name end of the secondary coil of the transformer module 110 are basically the same, therefore, the parallel high-frequency capacitor 130 also has no obvious ripple voltage and current fluctuations, so as to ensure the life and tolerance of the high-frequency capacitor 130, thereby improving the reliability of the DC conversion circuit 100.

[0065] It should also be noted that the combination form of the transformer module 110 and the combination form of the high-frequency capacitor 130 are not limited here.

[0066] In one possible implementation, if the output of the DC conversion circuit 100 is connected to no-load or light-load, since the load current is small under light-load or no-load, especially under no-load, the transformer parameters in the power circuit parameters such as leakage inductance, excitation inductance, parasitic capacitance, etc. all have an impact on the output of the DC conversion circuit 100. Therefore, a high-frequency capacitor 130 is connected in series between the same-name ends of the secondary coil of the transformer module 110, and the larger current in the bias of the DC conversion circuit 100 can be appropriately diverted to the branch with smaller current through the high-frequency capacitor 130 to achieve the transfer of high energy to the low-energy side, thereby alleviating the bias of the DC conversion circuit 100, and effectively achieving the current and voltage equalization control of the DC conversion circuit under light load or no-load, and only one high-frequency capacitor 130 is added, so that the structure of the DC conversion circuit is simple and the reliability is high.

[0067] In one possible implementation, if the output connection of the DC conversion circuit 100 is overloaded, a high-frequency capacitor 130 can be connected in series between the same-name ends of the secondary coil of the transformer module 110 to ensure that the output of the secondary coil of the transformer module 110 is equalized in current and voltage, thereby ensuring equalized current and voltage control of the DC conversion circuit.

[0068] It should be noted that the energy described in the embodiments of the present application can be understood as but not limited to the magnitude of the current.

[0069] An embodiment of the present application provides a DC conversion circuit, which may include a transformer module, N output branches and a high-frequency capacitor, where N is an integer greater than or equal to 2; the transformer module has N groups of positive and negative output terminals, the N groups of positive and negative output terminals are respectively connected to the positive and negative input terminals of the N output branches, and the positive and negative output terminals of the N output branches are used to output DC voltage; a high-frequency capacitor is connected between the same-name ends of the secondary coil of the transformer module. Therefore, the present application can connect the like-named ends of the transformer module by short-circuiting the high-frequency capacitor between the like-named ends of the transformer module, so that the DC conversion circuit can transfer the high-energy side to the low-energy side through the high-frequency capacitor when it is no-load, light-loaded or heavy-loaded, so that the energy between the like-named ends of the transformer module can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current in the DC conversion circuit; at the same time, since the DC conversion circuit in the present application only adds one high-frequency capacitor, the effect of equalizing current and voltage in the DC conversion circuit can be achieved, so that the structure of the DC conversion circuit is simple and the cost is low, and the high-frequency capacitor has a long life and a small size, thereby improving the reliability of the DC conversion circuit.

[0070] exist Figure 1 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Figure 2 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 2 .like Figure 2In the example, the transformation module 110 may include: at least two transformers 111.

[0071] Among them, the positive and negative output ends of the secondary coils of at least two transformers 111 are respectively N groups of positive and negative output ends; the electrical signals output by the positive and negative output ends of the secondary coils of the transformer module 110 are input through the positive and negative input ends of N output branches 120, and a DC voltage is output from the positive and negative output ends of the N output branches 120; the same-named ends of the secondary coils of the first transformer 111-1 in the two transformers 111 are designated, and the high-frequency capacitor 130 is connected between the same-named ends of the secondary coils of the second transformer 111-2, so that the same-named ends of the secondary coils of the adjacent first transformer 111-1 and the second transformer 111-2 in the two designated transformers 111 can be connected through the high-frequency capacitor 130, so that the larger current can be appropriately diverted to the branch with smaller current through the high-frequency capacitor 130, so as to realize the transfer of high energy to the low-energy side, thereby alleviating the bias condition of the DC conversion circuit 100, and thereby realizing the current and voltage equalization effect of the DC conversion circuit.

[0072] In one possible implementation, Figure 2 Taking the first transformer 111-1 and the second transformer 111-2 in the example, a high-frequency capacitor 130 is connected between the same-name end of the secondary coil of the first transformer 111-1 and the same-name end of the secondary coil of the second transformer 111-2, so that the secondary coils of the first transformer 111-1 and the second transformer 111-2 are connected in series through a high-frequency capacitor 130, and it is assumed that the current direction in the transformer module 110 is from top to bottom, that is, it flows from the secondary coil of the first transformer 111-1 to the secondary coil of the second transformer 111-2. When the secondary coil current of the first transformer 111-1 is greater than the secondary coil current of the second transformer 111-2, the secondary coil current of the first transformer 111-1 can be transferred to the secondary coil of the second transformer 111-2 through the high-frequency capacitor 130, so that the output currents of the secondary coils of the first transformer 111-1 and the second transformer 111-2 are the same, that is, the output currents of the secondary coils of the first transformer 111-1 and the second transformer 111-2 achieve a current sharing effect; when the secondary coil current of the first transformer 111-1 is less than the secondary coil current of the second transformer 111-2, the secondary coil current of the second transformer 111-2 can be charged to the secondary coil of the first transformer 111-1 through the high-frequency capacitor 130, so that the output currents of the secondary coils of the first transformer 111-1 and the second transformer 111-2 are the same, that is, the output currents of the secondary coils of the first transformer 111-1 and the second transformer 111-2 achieve a current sharing effect.

[0073] The embodiment of the present application provides a DC conversion circuit, wherein the transformer module may include: at least two transformers. The positive and negative output terminals of the secondary coils of at least two transformers are respectively N groups of positive and negative output terminals; the same-name terminal of the secondary coil of the first transformer in the two specified transformers is connected to a high-frequency capacitor with the same-name terminal of the secondary coil of the second transformer. Thus, the present application can connect a high-frequency capacitor between the same-name terminal of the secondary coil of the first transformer in the two specified transformers and the same-name terminal of the secondary coil of the second transformer, so that the energy between the same-name terminals of the two adjacent transformers (such as the first transformer and the second transformer) in the transformer module can be transferred and communicated, thereby making the outputs of the N output branches equalized or equalized, thereby achieving the effect of equalized voltage and equalized current of the DC conversion circuit.

[0074] exist Figure 2 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Figure 3 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 3 .like Figure 3 In the example, a high-frequency capacitor 130 is connected between the positive end of the secondary coil of the first transformer 111-1 and the positive end of the secondary coil of the second transformer 111-2, so that the high-frequency capacitor is short-circuited between the positive end of the secondary coil of the first transformer 111-1 and the positive end of the secondary coil of the second transformer 111-2, so as to connect the positive ends of the secondary coils of the first transformer 111-1 and the second transformer 111-2, so that when the DC conversion circuit is unloaded or lightly loaded, the high-energy side is transferred to the low-energy side through the high-frequency capacitor 130, so that the energy between the positive ends of the secondary coils of the first transformer 111-1 and the second transformer 111-2 can be transferred and communicated, so that the outputs of the N output branches are equalized in voltage or current, thereby achieving the equalization of voltage and current of the DC conversion circuit 100.

[0075] Optionally, the present application also provides an embodiment in which the negative same-name terminals of the secondary coils of the two transformers are connected to the high-frequency capacitor 130. Figure 4 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 4 .like Figure 4In the example, a high-frequency capacitor 130 is connected between the negative same-name end of the secondary coil of the first transformer 111-1 and the negative same-name end of the secondary coil of the second transformer 111-2, so that the high-frequency capacitor 130 is short-circuited between the negative same-name end of the secondary coil of the first transformer 111-1 and the negative same-name end of the secondary coil of the second transformer 111-2, so as to connect the negative same-name ends of the secondary coils of the first transformer 111-1 and the second transformer 111-2, so that the DC conversion circuit 100 transfers the high-energy side to the low-energy side through the high-frequency capacitor 130 when it is no-load or light-loaded, so that the energy between the negative same-name ends of the secondary coils of the first transformer 111-1 and the second transformer 111-2 can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the equalization of voltage and current of the DC conversion circuit 100.

[0076] Optionally, the present application further provides an embodiment in which the negative same-name terminals of the secondary coils of the two transformers are connected to the high-frequency capacitor 130-2, and the positive same-name terminals of the secondary coils of the two transformers are also connected to the high-frequency capacitor 130-1. Figure 2 On the basis of Figure 5 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 5 .like Figure 5 In the example, a high-frequency capacitor 130-1 is connected between the positive terminal of the secondary coil of the first transformer 111-1 and the positive terminal of the secondary coil of the second transformer 111-2, and a high-frequency capacitor 130-2 is connected between the negative terminal of the secondary coil of the first transformer 111-1 and the negative terminal of the secondary coil of the second transformer 111-2, that is, high-frequency capacitors are connected between the positive and negative terminals of the secondary coil of the first transformer 111-1 and the positive and negative terminals of the secondary coil of the second transformer 111-2, so that The connectivity effect of the like-named ends of the secondary coils of the first transformer 111-1 and the second transformer 111-2 is improved, so that the DC conversion circuit 100 transfers the high energy side to the low energy side through the two high-frequency capacitors 130 when it is no-load, light-loaded or heavy-loaded, so that the energy transfer efficiency between the like-named ends of the secondary coils of the first transformer 111-1 and the second transformer 111-2 is better, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit 100.

[0077] The DC conversion circuit provided by the embodiment of the present application, wherein a high-frequency capacitor is connected between the positive same-name end of the secondary coil of the first transformer and the positive same-name end of the secondary coil of the second transformer; and / or, a high-frequency capacitor is connected between the negative same-name end of the secondary coil of the first transformer and the negative same-name end of the secondary coil of the second transformer. Thus, the present application transfers the high-energy side to the low-energy side through the high-frequency capacitor, so that the energy transfer efficiency between the same-name ends of the secondary coils of the first transformer and the second transformer is better, thereby making the outputs of the N output branches equalized or equalized, thereby achieving the effect of equalized voltage and equalized current of the DC conversion circuit.

[0078] exist Figure 1 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Figure 6 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 6 .like Figure 6 In the example, the transformer module 110 may include: at least two groups of transformer units 112.

[0079] Each group of transformation units 112 may include: a first transformation sub-unit T1 and a second transformation sub-unit T2.

[0080] The positive and negative output ends of the secondary coils of the first transformer subunit T1 in at least two groups of transformer units 112, which are connected in series in sequence, are the first group of positive and negative output ends; the positive and negative output ends of the secondary coils of the second transformer subunit T2 in at least two groups of transformer units 112, which are connected in series in sequence, are the second group of positive and negative output ends; a high-frequency capacitor 130 is connected between the same-name ends of the secondary coils of the first transformer subunit T1 and the second transformer subunit T2, so that the same-name ends of the first group of positive and negative output ends and the second group of positive and negative output ends are connected through the high-frequency capacitor 130, so as to realize the transfer of the high-energy side to the low-energy side of the DC conversion circuit 100, so that the energy between the same-name ends of the first group of positive and negative output ends and the second group of positive and negative output ends can be transferred and communicated, thereby making the outputs of the N output branches 120 equal in voltage or current, thereby realizing the equalization of voltage and current of the DC conversion circuit 100.

[0081] In one possible implementation, Figure 6The first transformer subunit T1 and the second transformer subunit T2 in the first group of transformer units 112-1 and the first transformer subunit T1 and the second transformer subunit T2 in the second group of transformer units 112-2 are connected in series, then the first transformer subunit T1 in the first group of transformer units 112-1 and the first transformer subunit T1 in the second group of transformer units 112-2 are connected in series to obtain a first group of positive and negative output terminals; the second transformer subunit T2 in the first group of transformer units 112-1 and the second transformer subunit T2 in the second group of transformer units 112-2 are connected in series to obtain a first group of positive and negative output terminals; Elements T2 are connected in series to obtain a second group of positive and negative output terminals; the first group of positive and negative output terminals and the second group of positive and negative output terminals are both connected to the first output branch 120-1 and the second output branch 120-2; wherein, a high-frequency capacitor 130 is connected between the same-named ends of the first group of positive and negative output terminals and the second group of positive and negative output terminals, so that the energy between the first group of positive and negative output terminals and the same-named ends of the second group of positive and negative output terminals can be transferred and communicated, thereby making the outputs of the N output branches 120 equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit 100.

[0082] The embodiment of the present application provides a DC conversion circuit, wherein the transformer module includes: at least two groups of transformer units. Each group of transformer units includes: a first sub-transformer unit and a second sub-transformer unit; the positive and negative output ends of the secondary coils of the first sub-transformer unit in at least two groups of transformer units are connected in series in sequence as the first group of positive and negative output ends; the positive and negative output ends of the secondary coils of the second sub-transformer unit in at least two groups of transformer units are connected in series in sequence as the second group of positive and negative output ends; a high-frequency capacitor is connected between the same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit. Therefore, the present application can be achieved by connecting the secondary coils of the first sub-transformer units in at least two groups of transformer units in series in sequence; the secondary coils of the second sub-transformer units in at least two groups of transformer units in series in sequence, and a high-frequency capacitor is connected between the like-named ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit, so that the DC conversion circuit can transfer the high-energy side to the low-energy side through the high-frequency capacitor under no-load, light-load or heavy-load conditions, so that the energy between the like-named ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit in at least two groups of transformer units of the transformer module can be transferred and communicated, thereby making the outputs of N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0083] Optionally, in one implementation, Figure 6 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Figure 7 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 7 .like Figure 7In the example, a high-frequency capacitor 130-1 is connected between the positive like-name ends of the secondary coils of the first transformer subunit T1 and the second transformer subunit T2 in the first transformer unit 112-1 in the specified transformer unit 112, so that the positive like-name ends of the secondary coils of the first transformer subunit T1 and the second transformer subunit T2 are connected through the high-frequency capacitor 130-1, so as to transfer the high-energy side to the low-energy side through the high-frequency capacitor 130-1, so that the energy between the positive like-name ends of the secondary coils of the first transformer subunit T1 and the second transformer subunit T2 in the first transformer unit 112-1 can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0084] Optionally, in one implementation, Figure 6 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Figure 8 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 8 .like Figure 8 In the example, a high-frequency capacitor 130-2 is connected between the negative like-name ends of the secondary coils of the first transformer subunit T3 and the second transformer subunit T4 in the second transformer unit 112-2 in the specified transformer unit 112, so that the negative like-name ends of the secondary coils of the first transformer subunit T3 and the second transformer subunit T4 are connected through the high-frequency capacitor 130-2, so as to transfer the high energy side to the low energy side through the high-frequency capacitor 130-2, so that the energy between the negative like-name ends of the secondary coils of the first transformer subunit T3 and the second transformer subunit T4 in the first transformer unit 112-1 can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0085] The embodiment of the present application provides a DC conversion circuit, wherein a high-frequency capacitor is connected between the positive same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit in the first transformer unit in the specified transformer unit; or, a high-frequency capacitor is connected between the negative same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit in the second transformer unit in the specified transformer unit. Thus, the present application transfers the high-energy side to the low-energy side through the high-frequency capacitor, so that the energy transfer and communication efficiency between the same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit is better, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0086] Optionally, in one implementation, Figure 6 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Fig. 9 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 7 .like Fig. 9 In the example of FIG. 1 , a high-frequency capacitor 130-1 is connected between the positive same-name ends of the secondary coils of the first transformer subunit T1 and the second transformer subunit T2 in the first transformer unit 112-1 in the adjacent transformer units 112, and a high-frequency capacitor 130-2 is connected between the negative same-name ends of the secondary coils of the first transformer subunit T3 and the second transformer subunit T4 in the second transformer unit 112-2 in the adjacent transformer unit 112, so that the secondary coils of the first transformer subunit T1 and the second transformer subunit T2 in the first transformer unit 112-1 are connected. The positive like-name ends of the coils are connected through a high-frequency capacitor 130-1, and the negative like-name ends of the secondary coils of the first transformer sub-unit T1 and the second transformer sub-unit T2 in the second transformer unit 112-2 are connected through a high-frequency capacitor 130-2 to increase the efficiency of transferring from the high-energy side to the low-energy side, so that the energy between the like-name ends of the first transformer unit 112-1 and the second transformer unit 112-2 can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0087] It should be noted that, using a single high-frequency capacitor 130 to pull the energy between the like-named ends of the first transformer unit 112-1 and the second transformer unit 112-2 in adjacent transformer units 112, and using two high-frequency capacitors 130 to pull the energy between the like-named ends of the first transformer unit 112-1 and the second transformer unit 112-2 in adjacent transformer units 112, can both achieve energy transfer between the like-named ends of the first transformer unit 112-1 and the second transformer unit 112-2 in adjacent transformer units 112, but the current and voltage equalization efficiency of the DC conversion circuit of the two high-frequency capacitors 130 is higher than the current and voltage equalization efficiency of the DC conversion circuit of the single high-frequency capacitor 130, but the capacity of the single high-frequency capacitor 130 can also be increased to compensate for the above problem.

[0088] The embodiment of the present application provides a DC conversion circuit, wherein a high-frequency capacitor is connected between the positive same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit in the first transformer unit in the specified transformer unit; and a high-frequency capacitor is connected between the negative same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit in the second transformer unit in the specified transformer unit. Thus, the present application transfers the high-energy side to the low-energy side through the high-frequency capacitor, so that the energy transfer and communication efficiency between the same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit is better, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0089] Optionally, in one implementation, Figure 6 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Fig.10 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 .like Fig.10 In the example, a high-frequency capacitor 130 is connected between the first series connection point A of the secondary coil of the first transformer subunit T1 in the designated transformer unit 112 and the second series connection point B of the second transformer subunit T2 in the designated transformer unit 112, that is, the high-frequency capacitor 130 is connected between the first series connection point A and the second series connection point B, so that the first series connection point A and the second series connection point B are connected through the high-frequency capacitor 130 to achieve transfer from the high-energy side to the low-energy side, so that the energy between the first series connection point A and the second series connection point B can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the equalization of voltage and current of the DC conversion circuit.

[0090] In one possible implementation, Fig.11 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 1. As Fig.11 In the example, the negative output end of the first transformer subunit T1 in the first transformer unit 112-1 can be connected in series with the positive output end of the first transformer subunit T1 in the second transformer unit 112-2 to obtain a first series connection point A; the negative output end of the second transformer subunit T2 in the first transformer unit 112-1 can be connected in series with the positive output end of the second transformer T1 in the second transformer unit 112-2 to obtain a second series connection point B, and the first series connection point A and the second series connection point B are connected through a high-frequency capacitor 130 to achieve transfer from the high-energy side to the low-energy side, so that the energy between the first series connection point A and the second series connection point B can be transferred and communicated, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the equalization of voltage and current of the DC conversion circuit.

[0091] The embodiment of the present application provides a DC conversion circuit, wherein a high-frequency capacitor is connected between the first series connection point of the secondary coil of the first sub-transformer unit in the specified transformer unit and the second series connection point of the second sub-transformer unit. Thus, the present application transfers the high energy side to the low energy side through the high-frequency capacitor, so that the energy transfer and communication efficiency between the same-name ends of the secondary coils of the first sub-transformer unit and the second sub-transformer unit is better, thereby making the outputs of the N output branches equal in voltage or current, thereby achieving the effect of equalizing voltage and current of the DC conversion circuit.

[0092] exist Figure 1 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Fig.12 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 2. As Fig.12In the example, each output branch 120 may include: a rectifying unit 121 and a capacitor unit 122 .

[0093] The input end of the rectifier unit 121 is the positive and negative input end of each output branch 120, which is used to connect a group of positive and negative output ends of the transformer module 110; the output end of the rectifier unit 121 is connected to the two ends of the capacitor unit 122; the two ends of the capacitor unit 122 are the positive and negative output ends of each output branch 120, so that the output electrical signal of the transformer module 110 is rectified and output through the rectifier unit 121, and the output electrical signal of the transformer module 110 is adjusted through the capacitor unit 122 to ensure that the electrical signal output by the capacitor unit 122 is stable, so that the output of the capacitor unit 122 in the N output branches 120 meets the current and voltage sharing. The rectifier unit 121 is a unidirectional diode D with the same direction, wherein the diode D1 and the diode D3 are connected in series, the diode D2 and the diode D4 are connected in series, and the diode D1 and the diode D3 are connected in series and then connected in parallel with the diode D2 and the diode D4.

[0094] In one possible implementation, Figure 3 On the basis of Fig.13 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 3. As Fig.13 In the example, a high-frequency capacitor C1 is connected between the positive and negative ends of the secondary coil of the first transformer 111-1 of the two adjacent transformers 111 and the positive and negative ends of the secondary coil of the second transformer 111-2, and the positive and negative output ends of the secondary coil of the first transformer 111-1 are connected to the positive and negative input ends of the first rectifier unit 121-1 in the first output branch 120-1, the output end of the first rectifier unit 121-1 is connected to the two ends of the capacitor unit 122-1, the positive and negative output ends of the secondary coil of the second transformer 111-2 are connected to the positive and negative input ends of the second rectifier unit 121-2 in the second output branch 120-2, and the output end of the second rectifier unit 121-2 is connected to the two ends of the capacitor unit 122-2, so that the output electrical signals of the first output branch 120-1 and the second output branch 120-2 can achieve the effect of equalizing current and voltage.

[0095] In one possible implementation, Fig. 9 On the basis of Fig.14 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 4. Fig.14In the example, a high-frequency capacitor C1 is connected between the positive same-name ends of the secondary coils of the first transformer subunit T1 and the second transformer subunit T2 in the first transformer unit 112-1 in the specified transformer unit 112, and a high-frequency capacitor C2 is connected between the negative same-name ends of the secondary coils of the first transformer subunit T3 and the second transformer subunit T4 in the second transformer unit 112-2 in the adjacent transformer unit 112, the positive output end of the secondary coil of the first transformer subunit T1 in the first transformer unit 112-1 is connected to the positive input end of the first rectifier unit 121-1 in the first output branch 120-1, and the negative output end of the secondary coil of the first transformer subunit T1 in the second transformer unit 112-2 is connected to the negative same-name end of the secondary coil of the first transformer subunit T3 and the second transformer subunit T4 in the second transformer unit 112-2 in the adjacent transformer unit 112. A negative input terminal of a rectifier unit 121-1; an output terminal of the first rectifier unit 121-1 is connected to both ends of the capacitor unit 122-1; a positive output terminal of the secondary coil of the second transformer subunit T2 in the first transformer unit 112-1 is connected to the positive input terminal of the second rectifier unit 121-1 in the second output branch 120-2, and a negative output terminal of the secondary coil of the second transformer subunit T2 in the second transformer unit 112-2 is connected to the negative input terminal of the second rectifier unit 121-2 in the second output branch 120-2; an output terminal of the second rectifier unit 121-2 is connected to both ends of the capacitor unit 122-2, so that the output electrical signals of the first output branch 120-1 and the second output branch 120-2 can achieve the effect of equalizing current and voltage.

[0096] The embodiment of the present application provides a DC conversion circuit, wherein each output branch includes: a rectifier unit and a capacitor unit; wherein the input end of the rectifier unit is the positive and negative input end of each output branch, which is used to connect a group of positive and negative output ends of the transformer module; the output end of the rectifier unit is connected to the two ends of the capacitor unit; the two ends of the capacitor unit are the positive and negative output ends of each output branch. Thus, the present application can connect the two ends of the capacitor unit at the output end of the rectifier unit, so that the output of the secondary coil of the transformer module is output through each output branch, so that the output electrical signal of each output branch in the DC conversion circuit can achieve the effect of equal current and voltage.

[0097] exist Fig.13 Based on the above, the DC conversion circuit is explained and described in detail with reference to the accompanying drawings as follows: Fig.15 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 5. If Fig.15 In the example of , the N output branches 120 may further include: N−1 first switch units 123 , N−1 second switch units 124 , and N−1 third switch units 125 .

[0098] Among them, one end of the capacitor unit 122 in the first output branch of two adjacent output branches 120 is connected to one end of the capacitor unit 122 in the second output branch of two adjacent output branches through a first switch unit 123, so that the capacitor units 122 in the two adjacent output branches 120 are connected through the first switch unit 123, so that the two adjacent output branches 120 in the DC conversion circuit can be connected in series; the other end of the capacitor unit 122 in the first output branch is connected to the other end of the capacitor unit 122 in the second output branch through a second switch unit 124, and the capacitor unit 122 in the first output branch The other end of the unit 122 is connected to one end of the capacitor unit 122 in the second output branch through a third switch unit 125, so that the capacitor units 122 in two adjacent output branches 120 are connected through the second switch unit 124 and the third switch unit 125, so that the two adjacent output branches 120 in the DC conversion circuit can be connected in parallel; and then the DC conversion circuit can control the series and parallel connection of the DC conversion circuit by switching N-1 first switch units 123 and N-1 second switch units 124 and N-1 third switch units 125 to complete the wide constant power output of the DC conversion circuit.

[0099] It should be noted that when the first switch unit 123 is closed and the second switch unit 124 and the third switch unit 125 are both disconnected, the two adjacent output branches 120 are connected in series, and the capacitor units 122 in the two adjacent output branches 120 need to share the voltage; when the first switch unit 123 is disconnected and the second switch unit 124 and the third switch unit 125 are both closed, the capacitor units 122 in the two adjacent output branches 120 need to share the current.

[0100] In a possible implementation, taking two high frequency capacitors 130 as an example, Figure 16-Figure 17 The schematic diagrams of the structure of a DC conversion circuit provided by the embodiments of the present application are respectively shown, wherein: Fig.16 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 Six, such as Fig.16 In the example, taking at least two transformers 111 in the transformer module 110 as an example, the series and parallel connection of the DC conversion circuit is controlled by N-1 first switch units S1, N-1 second switch units S2, and N-1 third switch units S3 to complete the wide constant power output of the DC conversion circuit.

[0101] Fig.17 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 Seven, such as Fig.17In the example, taking at least two transformer units 112 in the transformer module 110 as an example, the series and parallel connection of the DC conversion circuit is controlled by N-1 first switch units S1, N-1 second switch units S2, and N-1 third switch units S3 to complete the wide constant power output of the DC conversion circuit.

[0102] In a possible implementation, taking a single high-frequency capacitor 130 and at least two transformer units 112 in a transformer module 110 as an example, Fig.18 A schematic diagram of a DC conversion circuit provided in an embodiment of the present application Figure 10 Eight, such as Fig.18 In the example, the series and parallel connection of the DC conversion circuit is controlled by N-1 first switch units S1, N-1 second switch units S2, and N-1 third switch units S3 to achieve wide constant power output of the DC conversion circuit.

[0103] It should be noted that there are many combinations of the transformer module and the high-frequency capacitor in the above-mentioned DC conversion circuit, which are not limited here. However, no matter which DC conversion circuit is used, the N output branches in the DC conversion circuit can control the series and parallel connection of the DC conversion circuit according to the N-1 first switch unit S1, the N-1 second switch unit S2 and the N-1 third switch unit S3 to complete the wide constant power output of the DC conversion circuit.

[0104] The embodiment of the present application provides a DC conversion circuit, wherein the N output branches further include: N-1 first switch units, N-1 second switch units, and N-1 third switch units, one end of the capacitor unit in the first output branch of two adjacent output branches is connected to one end of the capacitor unit in the second output branch of two adjacent output branches through a first switch unit, the other end of the capacitor unit in the first output branch is connected to the other end of the capacitor unit in the second output branch through a second switch unit, and the other end of the capacitor unit in the first output branch is connected to one end of the capacitor unit in the second output branch through a third switch unit. Thus, the N-1 first switch units, N-1 second switch units, and N-1 third switch units of the present application control the series connection and parallel connection of two adjacent output branches to complete the wide constant power output of the DC conversion circuit.

[0105] In order to more clearly understand the DC conversion circuit proposed in the embodiment of the present application, the present application provides an equivalent circuit of the DC conversion circuit. Fig.19 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 1 ,like Fig.19In the example, the transformer module 110 takes at least two transformers 111 as an example, and the negative like-name ends of the secondary coils of two adjacent transformers 111 are connected through a high-frequency capacitor C1, the positive and negative output ends of the secondary coil of each transformer 111 are connected to the positive and negative input ends of each output branch, and the first switch unit S1 is closed.

[0106] Taking transformer 111-1 and transformer 111-2 as examples, the currents of the secondary coils of transformer 111-1 and transformer 111-2 can be equivalent to two current sources with unequal currents, and the output currents are i1 and i2 respectively. The reference directions of current i1 and current i2 are Fig.19 As shown. Since the current i1 and the current i2 are sine waves of the same frequency, and the amplitude of the current i1 is greater than the amplitude of the current i2, and the first output branch 120-1 and the second output branch 120-2 are connected in series without voltage balancing, the voltage of the first capacitor unit C1 is greater than the voltage of the second capacitor unit C2, then if the DC conversion circuit is biased for a long time, the protection shutdown is caused to protect the components in the DC conversion circuit.

[0107] Since the outputs of the transformer 111 - 1 and the transformer 111 - 2 are two independent outputs, they form a loop respectively, and the current Io1+ is equal to the current Io1 −, and the current Io2+ is equal to the current Io2 −.

[0108] In one possible approach, Fig.19 As shown, the DC conversion circuit is in the negative half-cycle stable period. After the negative half-cycle stable period, since the diode D2 in the first output branch 120-1 and the diode D2 in the second output branch 120-2 are both normally turned on, the high-frequency capacitor C1 will be clamped at both ends of the voltage of the capacitor unit C2. At this time, the voltage bias of the capacitor unit C2 is slightly higher than the voltage of the capacitor unit C3, that is, Vo1>Vo2, that is, the voltage of the high-frequency capacitor C1 is larger.

[0109] In one possible approach, Fig. 20 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 2 ,like Fig. 20 As shown, the DC conversion circuit is in the positive half cycle transition period. After the positive half cycle starts, the diode D1 and the diode D4 in the second output branch 120-2 are normally turned on, and the current direction is as shown in FIG. Fig. 20As shown by the dotted arrow in , the high-frequency capacitor C1 starts to charge, and the diode D1 in the first output branch 120-1 is also turned on. Since the voltage of the high-frequency capacitor C1 is greater than the voltage of the capacitor unit C3 in the second output branch 120-2, the diode D4 in the first output branch 120-1 maintains the reverse voltage and does not conduct. Then the current i1 passes through the capacitor unit C2 and the capacitor unit C3, and then passes through the diode D4 in the second output branch 120-2 and the high-frequency capacitor C1, thereby forming a current loop; since the high-frequency capacitor C1 and the current i1 charge the output bus together, the voltage of the high-frequency capacitor C1 decreases. When the voltage of the high-frequency capacitor C1 decreases to the voltage of the capacitor unit C3, the diode D4 in the first output branch 120-1 is turned on, and the voltage of the high-frequency capacitor C1 is clamped by the voltage of the capacitor unit C3, resulting in a smaller voltage of the high-frequency capacitor C1.

[0110] It should be noted that, at this stage, the current i1 additionally charges the capacitor unit C3, resulting in the energy of the DC conversion circuit being partially transferred to the low-voltage side branch.

[0111] In one possible approach, Fig.21 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 3 ,like Fig.21 As shown, the DC conversion circuit is in the positive half cycle stable period. In the positive half cycle stable period, the outputs of the transformer 111-1 and the transformer 111-2 are two independent outputs, so that the transformer 111-1 and the transformer 111-2 each form a current loop with their respective output branches. The current direction is as shown in FIG. Fig.21 As shown by the dotted arrows in , at this time, the diode D1 and the diode D4 in the first output branch 120-1 are both normally turned on, and the diode D1 and the diode D4 in the second output branch 120-2 are both normally turned on, then the voltage of the high-frequency capacitor C1 is clamped by the voltage of the capacitor unit C3, resulting in a smaller voltage of the high-frequency capacitor C1.

[0112] In one possible approach, Fig. 22 A schematic diagram of an equivalent circuit of a DC conversion circuit provided in an embodiment of the present application Figure 4 ,like Fig. 22As shown, the DC conversion circuit is in the negative half-cycle transition period. After the negative half-cycle starts, since the voltage of the high-frequency capacitor C1 is less than the voltage of the capacitor unit C2, the current i1 will preferentially charge the low-voltage side of the high-frequency capacitor C1. The circuit loop passes through the high-frequency capacitor C1 and the diode D1 in the second output branch 120-2 to the diode D3 in the first output branch 120-1. At this time, the voltage of the high-frequency capacitor C1 gradually increases, and the voltage supplied by the capacitor unit C2 to the load gradually decreases. After the voltage of the high-frequency capacitor C1 is charged higher than the voltage of the capacitor unit C2, the diode D2 in the first output branch 120-1 is switched to conduct, and the stable period of the negative half-cycle is entered.

[0113] Through the above Figure 19-22 According to the analysis, it can be known that by charging the high-frequency capacitor C1 to supplement the energy of the capacitor unit C3 with lower energy, and discharging the high-frequency capacitor C1 for continuous current, the charging energy of the capacitor unit C2 is reduced, so that the discharge voltage of the capacitor unit C2 is reduced. Therefore, by short-circuiting the high-frequency capacitor C1 between the same-name terminals, the voltage of the high-frequency capacitor C1 is converted between the voltage of the first output branch 120-1 and the voltage of the second output branch 120-2 to achieve energy storage and transfer, thereby achieving voltage and current balancing effects, so that the series bias is suppressed, the voltage difference between the capacitor unit C2 and the capacitor unit C3 is reduced, the ripple is small, suitable for long-term work, reliable and long life.

[0114] Furthermore, after clearly describing the DC conversion circuit provided by the present application, the charging module provided by the present application is described in detail. Fig.23 This is a schematic diagram of the structure of a charging module provided in an embodiment of the present application. Fig.23 As shown, the charging module 300 may include: a DC conversion circuit 100 and a rectifier circuit 200 .

[0115] The rectifier circuit 200 is connected to the preset AC power supply and the input end of the DC conversion circuit 100, and the rectifier circuit 200 is used to convert the AC voltage output by the preset AC power supply into a DC voltage, so as to input the DC voltage into the DC conversion circuit 100, so as to provide working power to the DC conversion circuit 100. The preset AC power supply can be selected according to actual conditions, for example, the preset AC power supply can be selected as a preset power grid, etc., which is not limited here.

[0116] The charging module provided in the embodiment of the present application may include a DC conversion circuit and a rectifier circuit; wherein the rectifier circuit is connected to a preset AC power supply and an input end of the DC conversion circuit; and the rectifier circuit is used to convert the AC voltage output by the preset AC power supply into a DC voltage. Therefore, the present application converts the AC voltage of the preset AC power supply into a DC voltage through the rectifier circuit to control the input of the DC conversion circuit.

[0117] After clearly describing the DC conversion circuit provided by the present application, the charging module provided by the present application is described in detail. Fig.24 This is a schematic diagram of the structure of a charging pile provided in an embodiment of the present application. Fig.24 As shown, the charging pile 400 may include: at least one charging module 300 and a control module 410 .

[0118] The control module 410 is connected to the charging module 300 so that the control module 410 controls the charging module 300 to charge the object to be charged. The object to be charged can be selected according to actual conditions, for example, the object to be charged can be selected as a vehicle to be charged.

[0119] The charging pile provided in the embodiment of the present application may include at least one charging module and a control module, the control module is connected to the charging module, and the control module is used to control the charging module to charge the object to be charged. Therefore, the present application can realize the charging function of the charging pile by using the control module to control the charging module to charge the object to be charged.

[0120] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A DC conversion circuit, characterized in that: The DC conversion circuit comprises: a voltage conversion module, N output branches and a high-frequency capacitor, where N is an integer greater than or equal to 2; The transformer module has N groups of positive and negative output terminals, the N groups of positive and negative output terminals are respectively connected to the positive and negative input terminals of the N output branches, and the positive and negative output terminals of the N output branches are used to output a DC voltage; The high-frequency capacitor is connected between the same-name ends of the secondary coil of the transformer module.

2. The DC conversion circuit according to claim 1, characterized in that: The transformer module comprises: at least two transformers, the positive and negative output ends of the secondary coils of the at least two transformers are respectively the N groups of positive and negative output ends; The high-frequency capacitor is connected between the same-name end of the secondary coil of the first transformer and the same-name end of the secondary coil of the second transformer.

3. The DC conversion circuit according to claim 2, characterized in that: The high-frequency capacitor is connected between the positive end of the secondary coil of the first transformer and the positive end of the secondary coil of the second transformer; And / or, the high-frequency capacitor is connected between the negative same-name end of the secondary coil of the first transformer and the negative same-name end of the secondary coil of the second transformer.

4. The DC conversion circuit according to claim 1, characterized in that: The transformer module comprises: at least two groups of transformer units, each group of transformer units comprises: a first sub-transformation unit and a second sub-transformation unit; The positive and negative output ends of the secondary coils of the first sub-transformer units in the at least two groups of transformer units, which are connected in series in sequence, are the first group of positive and negative output ends; the positive and negative output ends of the secondary coils of the second sub-transformer units in the at least two groups of transformer units, which are connected in series in sequence, are the second group of positive and negative output ends; The high-frequency capacitor is connected between the same-name ends of the secondary coils of the first sub-transformation unit and the second sub-transformation unit.

5. The DC conversion circuit according to claim 4, characterized in that: The high-frequency capacitor is connected between the positive ends of the secondary coils of the first sub-transformation unit and the second sub-transformation unit in the first transformation unit in the designated transformation unit; And / or, the high-frequency capacitor is connected between negative same-name ends of the secondary coils of the first sub-transformation unit and the second sub-transformation unit in the second transformation unit in the designated transformation unit.

6. The DC conversion circuit according to claim 4, characterized in that: The high-frequency capacitor is connected between a first series connection point of the secondary coil of the first sub-transformer unit in the designated transformer unit and a second series connection point of the second sub-transformer unit.

7. The DC conversion circuit according to claim 1, characterized in that: Each output branch includes: a rectifier unit and a capacitor unit; wherein the input end of the rectifier unit is the positive and negative input end of each output branch, which is used to connect a group of positive and negative output ends of the transformer module; The output end of the rectifier unit is connected to the two ends of the capacitor unit; the two ends of the capacitor unit are the positive and negative output ends of each output branch.

8. The DC conversion circuit according to claim 7, characterized in that: The N output branches further include: N-1 first switch units, N-1 second switch units and N-1 third switch units; One end of the capacitor unit in the first output branch of two adjacent output branches is connected to one end of the capacitor unit in the second output branch of the two adjacent output branches through a first switching unit, the other end of the capacitor unit in the first output branch is connected to the other end of the capacitor unit in the second output branch through a second switching unit, and the other end of the capacitor unit in the first output branch is connected to one end of the capacitor unit in the second output branch through a third switching unit.

9. A charging module, characterized in that: include: The DC conversion circuit and the rectifier circuit as described in any one of claims 1-8; wherein the rectifier circuit is connected to a preset AC power supply and an input end of the DC conversion circuit; and the rectifier circuit is used to convert the AC voltage output by the preset AC power supply into a DC voltage.

10. A charging pile, characterized in that: include: At least one charging module and a control module as claimed in claim 9, wherein the control module is connected to the charging module, and the control module is used to control the charging module to charge the object to be charged.

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