CN216929879U

CN216929879U - LLC resonant transformation ware, module and fill electric pile charge of charging

Info

Publication number: CN216929879U
Application number: CN202220204923.9U
Authority: CN
Inventors: 彭玉成; 李维旭; 田超
Original assignee: Hebei Tonghe New Energy Technology Co ltd
Current assignee: Hebei Tonghe New Energy Technology Co ltd
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2022-07-08
Anticipated expiration: 2032-01-25

Abstract

The utility model belongs to the technical field of power electronics, and provides an LLC resonant converter, a charging module and a charging pile, wherein the LLC resonant converter comprises at least two switch loops, at least two resonant loops and at least two rectifying loops; each resonant circuit comprises a resonant capacitor, a first resonant inductor, a second resonant inductor and a current-sharing transformer, the resonant capacitor, the first resonant inductor, the second resonant inductor and a primary winding of the current-sharing transformer are connected in series to form a first series circuit of the resonant circuit, and two ends of the first series circuit are used as input ends of the resonant circuit and are correspondingly connected with the output end of one switch circuit; the second resonant inductors of the resonant circuits are coupled with each other in a forward direction; and secondary windings of the current equalizing transformers in the resonant circuits are equally and alternately connected. The LLC resonant converter is small in size, and multi-channel LLC topology current sharing is achieved.

Description

LLC resonant transformation ware, module and fill electric pile of charging

Technical Field

The utility model belongs to the technical field of power electronics, and particularly relates to an LLC resonant converter, a charging module and a charging pile.

Background

In the field of new energy vehicles, a charging module in the charging pile industry is used as a core module of a direct-current charging pile, and along with the increase of energy density of a battery, the increase of allowable charging current, the cost of a complete machine of a product and other factors, the requirement on the power density of the product is higher and higher, and the output power is higher and higher. The LLC topology is used as a high-frequency soft switch topology, is particularly suitable for application occasions of inputting high voltage, outputting high voltage and outputting high power, is limited by the output power capability of the current semiconductor device and magnetic components, still needs a plurality of ways of LLC topologies to work and output in parallel, improves the total output power of products, and can meet the use requirement of the charging pile industry. However, when multiple LLC topologies are connected in parallel, the problems of non-uniform current and large product volume exist.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an LLC resonant converter, a charging module and a charging pile, and aims to reduce the volume of a plurality of paths of LLC topologies and realize current sharing of the plurality of paths of LLC topologies.

To achieve the above object, a first aspect of an embodiment of the present invention provides an LLC resonant converter, including:

at least two switching loops, at least two resonant loops, at least two rectifying loops;

the input ends of the switch loops are connected in parallel to form the input end of the LLC resonant converter;

each resonant circuit comprises a resonant capacitor, a first resonant inductor, a second resonant inductor and a current-sharing transformer, wherein the resonant capacitor, the first resonant inductor, the second resonant inductor and a primary winding of the current-sharing transformer in each resonant circuit are connected in series to form a first series circuit of the resonant circuit, and two ends of the first series circuit of the resonant circuit form the input end of the resonant circuit; the input end of each resonant circuit is correspondingly connected with the output end of one switching circuit; the second resonant inductors of the resonant circuits are coupled with each other in a forward direction;

the secondary windings of the current sharing transformers in each resonant circuit are equally divided into N sections, and the N sections of secondary windings in all the resonant circuits are connected in series to form N second series circuits; each second series circuit comprises a section of secondary winding of each resonant circuit, the secondary windings in each second series circuit are not repeated, and N is the number of the resonant circuits; the two ends of each second series circuit are correspondingly connected with the input end of one rectifying circuit; and the output end of each rectification loop is connected to form the output end of the LLC resonant converter.

Optionally, the output ends of the rectifying loops are connected in parallel to form the output end of the LLC resonant converter.

Optionally, the output ends of the rectifying loops are connected in series to form the output end of the LLC resonant converter.

Optionally, the input end of the LLC resonant converter includes a positive input end and a negative input end; an input capacitor is connected between the positive input end and the negative input end.

Optionally, the output end of the LLC resonant converter includes a positive output end and a negative output end; an output capacitor is connected between the positive output end and the negative output end.

Optionally, the second resonant inductors of the resonant circuits are wound around the same iron core magnetic column in a double-line manner, so as to realize forward magnetic coupling.

Optionally, the switch loop is a full-bridge type switch loop or a half-bridge type switch loop.

Optionally, the rectifying circuit is a diode rectifying bridge.

A second aspect of embodiments of the present invention provides a charging module comprising an LLC resonant converter as described in the first aspect above.

A third aspect of the embodiments of the present invention provides a charging pile, including the charging module according to the second aspect.

Compared with the prior art, the embodiment of the utility model has the following beneficial effects:

the embodiment of the utility model adopts a magnetic integration scheme, namely, a first resonant inductor and a second resonant inductor are connected in series in each resonant circuit, and the current sharing of two LLC topologies is realized by the forward magnetic coupling of the second resonant inductor of each resonant circuit and the cooperation of the external first resonant inductor; and the secondary windings of the current-sharing transformers are connected in a sharing and staggered manner, so that the current of each rectifying loop is completely shared. The LLC resonant converter provided by the embodiment of the utility model has a small volume, and realizes multi-channel LLC topology current sharing.

Drawings

Fig. 1 is a first schematic structural diagram of an LLC resonant converter provided in an embodiment of the present invention;

fig. 2 is a second schematic structural diagram of an LLC resonant converter provided in the embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and do not limit the utility model.

Referring to fig. 1 and fig. 2 together, an LLC resonant converter according to an embodiment of the present invention will now be described. The LLC resonant converter comprises:

at least two switching loops, at least two resonant loops, at least two rectifying loops.

Generally, a set of corresponding switching loop, resonant loop and rectifying loop can be regarded as a single LLC topology, and this embodiment is described by taking the two LLC topologies shown in fig. 1 and fig. 2 as an example. It can be understood that the implementation is the same for LLC resonant converters of more than two LLC topologies.

For example, as shown in fig. 1 and 2, the input terminals of the respective switching circuits are connected in parallel to form the positive and negative input terminals of the LLC resonant converter. Each resonant circuit comprises a resonant capacitor C₀First resonant inductor L₁A second resonant inductor L₂And a current sharing transformer T. Resonant capacitance C in each resonant tank₀A first resonant inductor L₁A second resonant inductor L₂And the primary winding of the current sharing transformer T is connected in series to form a first series circuit of the resonant circuit, and two ends of the first series circuit of the resonant circuit form the input end of the resonant circuit. Each resonanceThe input ends of the loops are correspondingly connected with the output end of one switch loop.

Second resonant inductance L of each resonant tank₂With positive magnetic coupling therebetween.

N sections of secondary windings in all the resonant circuits are connected in series to form N second series circuits; each second series circuit comprises a section of secondary winding of each resonant circuit, the secondary windings in each second series circuit are not repeated, and N is the number of the resonant circuits.

For example, in fig. 1 and fig. 2, the secondary winding of the current sharing transformer T in each resonant tank is equally divided into two sections, one section of the secondary winding is selected from each current sharing transformer T to be connected in series to form a second series circuit, and two ends of the second series circuit are correspondingly connected to the input end of one rectifying circuit. Optionally, as shown in fig. 1, output terminals of the respective rectifying loops are connected in parallel to form a positive output terminal and a negative output terminal of the LLC resonant converter. Alternatively, as shown in fig. 2, the output terminals of the respective rectifying circuits are connected in series to constitute the output terminal of the LLC resonant converter.

In the embodiment of the utility model, two LLC topologies are linked through a magnetic integration design, a first resonant inductor and a second resonant inductor are connected in series in each resonant circuit, the non-uniform current caused by the device difference of the two LLC topologies and the like is counteracted through the forward magnetic coupling of the second resonant inductor of each resonant circuit and the cooperation of the external first resonant inductor, and the current of each rectifying circuit is ensured to be completely uniformly distributed by uniformly distributing and interleaving secondary windings of each current-sharing transformer. The LLC resonant converter provided by the embodiment of the utility model has a small volume, and realizes multi-channel LLC topology current sharing.

Optionally, referring to fig. 1 and 2, the input terminal of the LLC resonant converter includes a positive input terminal and a negative input terminal, and an input capacitor C is connected between the positive input terminal and the negative input terminal_in。

Optionally, referring to fig. 1 and 2, the output terminal of the LLC resonant converter includes a positive output terminal and a negative output terminal, and an output capacitor C is connected between the positive output terminal and the negative output terminal_out。

Alternatively to this, the first and second parts may,second resonant inductance L of each resonant tank₂The double wires are wound around the same iron core magnetic column to realize forward magnetic coupling.

In the embodiment of the utility model, the second resonant inductor L of each resonant loop₂By adopting a double-line parallel winding mode, the consistency of the inductance can be ensured, and uneven current caused by the difference of devices of two LLC topologies is offset. In addition, a second resonant inductor L can be realized by winding on an iron core magnetic column in a multi-layer printed board mode and the like₂The present application is not limited thereto.

Fig. 1 and fig. 2 shown in the embodiment of the present invention are all full-bridge type switch loops, and it can be understood that this scheme can still be implemented by using similar topologies such as a symmetric half-bridge type switch loop, an asymmetric half-bridge type switch loop, and the like, and the connection mode is the same as that of the full-bridge type switch loop, which is not described herein again.

Optionally, referring to fig. 1 and 2, the rectifying circuit is a diode rectifying bridge.

Optionally, series-parallel switching of the rectifier circuits may be realized through a relay and a semiconductor, so that each rectifier circuit may operate in a series mode or a parallel mode.

The LLC resonant converter based on magnetic integration can greatly reduce the volume of the whole product, improve the power density of the product and simultaneously solve the problem of parallel current sharing of a plurality of LLC circuits.

An embodiment of the present invention provides a charging module, including the LLC resonant converter as described above.

The embodiment of the utility model also provides a charging pile, which comprises the charging module.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. An LLC resonant converter, comprising:

the secondary windings of the current equalizing transformers in each resonant circuit are equally divided into N sections, and the N sections of secondary windings in all the resonant circuits are connected in series to form N second series circuits; each second series circuit comprises a section of secondary winding of each resonant circuit, the secondary windings in each second series circuit are not repeated, and N is the number of the resonant circuits; both ends of each second series circuit are correspondingly connected with the input end of one rectifying circuit; and the output end of each rectification loop is connected with the output end of the LLC resonant converter.

2. LLC resonant converter as claimed in claim 1, characterized in that the outputs of the respective rectifying circuits are connected in parallel to form the output of the LLC resonant converter.

3. LLC resonant converter as claimed in claim 1, characterized in that the outputs of the respective rectifying circuits are connected in series to form the output of the LLC resonant converter.

4. The LLC resonant converter of claim 1, wherein the input terminals of the LLC resonant converter comprise a positive input terminal and a negative input terminal;

an input capacitor is connected between the positive input end and the negative input end.

5. The LLC resonant converter of claim 1, wherein the output of the LLC resonant converter comprises a positive output and a negative output;

an output capacitor is connected between the positive output end and the negative output end.

6. The LLC resonant converter as claimed in claim 1, wherein the second resonant inductors of the respective resonant tanks are bifilar and wound around the same core leg to achieve forward magnetic coupling.

7. LLC resonant converter as claimed in any of claims 1-6, wherein said switching loop is a full-bridge type switching loop or a half-bridge type switching loop.

8. LLC resonant converter as claimed in any of claims 1-6, characterized in that said rectifying circuit is a diode rectifier bridge.

9. A charging module comprising an LLC resonant converter as claimed in any one of claims 1-8.

10. A charging pile characterized by comprising the charging module according to claim 9.