阅读说明：本技术 一种电源变换模块的均压装置以及一种电源变换系统 (Voltage-sharing device of power conversion module and power conversion system ) 是由 吴新科 范高 黄新隆 于 2021-07-29 设计创作，主要内容包括：本申请公开了一种电源变换模块的均压装置,包括：N个电源变换模块；其中,第1个电源变换模块的第一端与第N个电源变换模块的第二端并联,第N-i个电源变换模块的第二端与第N-i+1个电源变换模块的第一端并联；N≥2,1≤i≤N-1。通过该均压装置因为可以实现N个电源变换模块的完全串联,所以,通过该装置就可以完全承受N个电源变换模块的输入电压或输出电压,由此就会显著提高电源变换模块的利用率。并且,在该均压方式中,每一个电源变换模块中的所有变压器绕组均可以传输功率,在此情况下,利用该装置也可以提高电源变换模块中变压器绕组的利用率。(The application discloses voltage-sharing device of power conversion module includes: n power supply conversion modules; the first end of the 1 st power supply conversion module is connected with the second end of the Nth power supply conversion module in parallel, and the second end of the N-i power supply conversion module is connected with the first end of the (N-i + 1) th power supply conversion module in parallel; n is more than or equal to 2, i is more than or equal to 1 and less than or equal to N-1. Because the voltage equalizing device can realize the complete series connection of the N power supply conversion modules, the voltage equalizing device can completely bear the input voltage or the output voltage of the N power supply conversion modules, thereby obviously improving the utilization rate of the power supply conversion modules. In this voltage equalizing method, power can be transmitted to all the transformer windings in each power conversion module, and in this case, the utilization rate of the transformer windings in the power conversion modules can be increased by this device.)

1. The utility model provides a voltage-sharing device of power conversion module which characterized in that includes: n power supply conversion modules; the first end of the 1 st power supply conversion module is connected with the second end of the Nth power supply conversion module in parallel, and the second end of the N-i power supply conversion module is connected with the first end of the (N-i + 1) th power supply conversion module in parallel; n is more than or equal to 2, i is more than or equal to 1 and less than or equal to N-1.

2. The voltage sharing device according to claim 1, wherein when the number of the power conversion modules is 2, the first end and the second end of the power conversion module are the same port.

3. The voltage equalizing device according to claim 1, wherein when the power conversion module only needs to be connected in parallel with one equalized power conversion module group for voltage equalizing, the first end and the second end of the power conversion module are the same port, and the first end of the power conversion module is connected in parallel with the voltage equalizing port of the power conversion module group.

4. The voltage equalizing device of claim 1, wherein said power conversion module comprises at least one transformer.

5. The voltage equalizer according to claim 1, wherein the voltages at the ports of the N power conversion modules are the same.

6. The voltage equalizer according to claim 1, wherein the voltages at the ports of the N power conversion modules are set according to a predetermined ratio.

7. The voltage equalizing device according to claim 1, wherein if the power supplies of the N power conversion modules are direct current, the control signals of the N power conversion modules are independent of each other.

8. The voltage equalizing device of claim 1, wherein the parallel ports are capable of series-parallel combination.

9. The voltage sharing device according to any one of claims 1 to 8, wherein the power conversion module comprises a single power conversion unit and/or a plurality of power conversion units after voltage sharing.

10. A power conversion system comprising a voltage equalizing device of a power conversion module according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of power converters, in particular to a voltage equalizing device of a power conversion module and a power conversion system.

Background

In the application of the power conversion module, a plurality of power conversion modules are usually connected in series and in parallel to enable the existing power conversion module to develop a circuit topology structure required by the application. When the power conversion modules are connected in series and in parallel, it is generally desirable that the voltage stress borne by each power conversion module is the same or keeps a fixed proportion, so as to ensure stable and reliable operation of the whole circuit topology. However, due to the problems of process deviation and operating state difference of the internal devices of each power conversion module, the operating voltage of each power conversion module may deviate from the expected value to a certain extent, and even the deviation value may gradually increase with the operation of the circuit. In this case, a certain voltage-sharing measure is required to ensure that the voltages borne by the power conversion modules are the same or maintain a certain proportion.

In the prior art, the following two methods are generally adopted to perform voltage equalization on the series-parallel power conversion modules. One of them is to equalize the voltage of the power conversion module according to the "power converter topology capable of equalizing voltage and expanding power" provided in patent application 201120283946.5, where a 2N power conversion module is provided in the topology circuit, but the entire power conversion topology can only bear the input voltages of N power conversion modules, which results in a low utilization rate of the power conversion module; another approach is to use an automatic voltage equalizer circuit to equalize the voltage of the power conversion modules as provided in patent application 201921047152.1, but during normal operation of the voltage equalizer circuit, the auxiliary winding of the transformer does not carry power, which results in a low utilization of the transformer winding. At present, no effective solution exists for the above technical problems.

Therefore, how to improve the utilization rate of the transformer winding in the power conversion module while improving the utilization rate of the power conversion module is a problem to be solved urgently by those skilled in the art.

Disclosure of Invention

In view of the above, the present invention provides a voltage equalizing device for a power conversion module and a power conversion system, so as to improve the utilization rate of the power conversion module and the utilization rate of the transformer winding in the power conversion module. The specific scheme is as follows:

a voltage-sharing device of a power conversion module comprises: n power supply conversion modules; the first end of the 1 st power supply conversion module is connected with the second end of the Nth power supply conversion module in parallel, and the second end of the N-i power supply conversion module is connected with the first end of the (N-i + 1) th power supply conversion module in parallel; n is more than or equal to 2, i is more than or equal to 1 and less than or equal to N-1.

Preferably, when the number of the power conversion modules is 2, the first end and the second end of the power conversion modules are the same port.

Preferably, when the power conversion module only needs to be connected in parallel with one equalized power conversion module group for voltage equalization, the first end and the second end of the power conversion module are the same port, and the first end of the power conversion module is connected in parallel with the voltage equalization port of the power conversion module group.

Preferably, the power conversion module has at least one transformer.

Preferably, the voltages of the ports of the N power conversion modules are the same.

Preferably, the voltage of each port of the N power conversion modules is set according to a preset ratio.

Preferably, if the power supplies of the N power conversion modules are direct currents, the control signals of the N power conversion modules are independent of each other.

Preferably, the ports after parallel connection can be combined in series and parallel connection.

Preferably, the power conversion module includes a single power conversion unit and/or a plurality of power conversion units after voltage equalization.

Correspondingly, the invention also discloses a power supply conversion system which comprises the voltage-sharing device of the power supply conversion module.

Therefore, the voltage equalizing device provided by the invention can realize the complete series connection of the N power supply conversion modules, so that the device can completely bear the input voltage or the output voltage of the N power supply conversion modules, thereby obviously improving the utilization rate of the power supply conversion modules. In this voltage equalizing method, power can be transmitted to all the transformer windings in each power conversion module, and in this case, the utilization rate of the transformer windings in the power conversion modules can be increased by this device. Correspondingly, the power supply conversion system provided by the invention also has the beneficial effects.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a structural diagram of voltage-sharing connection of dc output sides of N power conversion modules;

fig. 2 is a structural diagram of voltage-sharing connection of the dc output sides of 3 power conversion modules;

fig. 3 is a structural diagram of voltage-sharing connection of the ac input sides of 3 power conversion modules;

fig. 4 is a structural view of the voltage-sharing connection of the ac output sides of 3 power conversion modules;

FIG. 5 is a structural diagram of voltage-sharing connection between DC output sides of 2 power conversion modules;

fig. 6 is another structural view when voltage-sharing connection is performed on the dc output side of 2 power conversion modules;

FIG. 7 is a block diagram of an LLC resonant circuit with two output ports;

fig. 8 is a structural diagram of voltage-sharing connection of dc output ports of 3 power conversion modules;

fig. 9 is a structural diagram of voltage-sharing connection of winding ports of 3 power conversion modules;

fig. 10 is a schematic diagram of a voltage-sharing device provided with 4 power conversion modules, each of which has a control signal;

FIG. 11 is a diagram illustrating the results of the control signal interleaving performed by the 4 power conversion modules shown in FIG. 10;

fig. 12 is a structural diagram of three parallel port groups connected in series to serve as input ports of the entire voltage-sharing device;

fig. 13 is a structural diagram of three groups of parallel ports connected in series to serve as output ports of the whole voltage-sharing device;

FIG. 14 is a schematic diagram of a connection of 3 power conversion modules when the parallel voltage sharing port is not used for power transfer;

fig. 15 is a connection structure diagram when 6 output ports of two power conversion modules are connected in a voltage-sharing manner.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention provides a voltage-sharing device of a power supply conversion module, which comprises: n power supply conversion modules; the first end of the 1 st power supply conversion module is connected with the second end of the Nth power supply conversion module in parallel, and the second end of the N-i power supply conversion module is connected with the first end of the (N-i + 1) th power supply conversion module in parallel; n is more than or equal to 2, i is more than or equal to 1 and less than or equal to N-1;

in this embodiment, a voltage equalizing device for a power conversion module is provided, by which not only the utilization rate of the power conversion module but also the utilization rate of a transformer winding in the power conversion module can be improved.

Referring to fig. 1, fig. 1 is a structural diagram of voltage-sharing connection between dc output sides of N power conversion modules. Based on the same principle, the voltage of the N power conversion modules can be equalized by connecting the input side ports of the power conversion modules. Wherein the power conversion module comprises a capacitor C_{in_i}And transformers T, V_o1And V_o2A first output port and a second output port of the transformer T, respectively. Referring to fig. 2, fig. 2 is a structural diagram of voltage-sharing connection between dc output sides of 3 power conversion modules.

Referring to fig. 3, fig. 3 is a structural diagram of voltage-sharing connection between the ac input sides of 3 power conversion modules. The voltage-sharing device is provided with 3 power conversion modules, namely a first power conversion module, a second power conversion module and a third power conversion module. Wherein each power conversion module comprises a capacitor C_{in_i}The first winding P1 and the second winding P2 of the transformer T1 in the first power conversion module are respectively equivalent to the first end and the second end of the first power conversion module, similarly, the first winding P3 and the second winding P4 of the transformer T2 in the second power conversion module are respectively equivalent to the first end and the second end of the second power conversion module, and the first winding P5 and the second winding P6 of the transformer T3 in the third power conversion module are respectively equivalent to the first end and the second end of the third power conversion module.

In the voltage equalizing device of the power conversion module shown in fig. 3, the voltage equalizing is performed for the 3 power conversion modules by connecting the primary windings of the power conversion modules. Based on the same principle, the voltage of the 3 power conversion modules can be equalized by connecting the secondary windings of the power conversion modules. Referring to fig. 4, fig. 4 is a structural diagram of the voltage-sharing connection between the ac output sides of the 3 power conversion modules.

In the voltage equalizing device, because the N power conversion modules can be completely connected in series, the device can completely bear the input voltage or the output voltage of the N power conversion modules, and therefore the utilization rate of the power conversion modules can be obviously improved. And when the parallel ports are used as the output of the voltage equalizing device, each port can transmit energy, so that the utilization rate of a transformer winding in the power supply conversion module can be obviously improved.

It should be noted that, in the voltage equalizing device provided in this embodiment, the voltage stress borne by each power conversion module is the same or maintains a fixed proportion; moreover, the transformer in each power conversion module may be a wire-wound transformer, a planar transformer, or another type of transformer. Meanwhile, the voltage equalizing device can be used for carrying out average voltage equalizing on the N power supply conversion modules and carrying out voltage equalizing on the N power supply conversion modules in proportion.

Therefore, the voltage equalizing device provided by the invention can realize the complete series connection of the N power supply conversion modules, so that the device can completely bear the input voltage or the output voltage of the N power supply conversion modules, thereby obviously improving the utilization rate of the power supply conversion modules. In this voltage equalizing method, power can be transmitted to all the transformer windings in each power conversion module, and in this case, the utilization rate of the transformer windings in the power conversion modules can be increased by this device.

Based on the above embodiments, this embodiment further describes and optimizes the technical solution, as a preferred implementation, when the number of the power conversion modules is 2, the first end and the second end of the power conversion module are the same port.

If there are 2 power conversion modules in the voltage equalizing device of the power conversion module, the first output end V of the transformer T1 in the first power conversion module may be used_o1And a second output end V of a transformer T2 in the second power supply conversion module_o2Parallel connection is carried out, and a second output end V of a transformer T1 in the first power supply conversion module is connected_o2And the first output end V of the transformer T2 in the second power supply conversion module_o1The two power conversion modules are connected in parallel to realize automatic voltage sharing. Referring to fig. 5, fig. 5 is a structural diagram of voltage-sharing connection between the dc output sides of 2 power conversion modules.

Or, the first port and the second port in the power conversion module are set as the same port, that is, only one port is set at the output end of the power conversion module, and then the first output end V of the transformer T1 in the first power conversion module is set_o1And a first output end V of a transformer T2 in the second power supply conversion module_o1The purpose of voltage sharing of the two power supply conversion modules can be achieved by parallel connection. Specifically, referring to fig. 6, fig. 6 is another structural diagram of voltage-sharing connection between the dc output sides of 2 power conversion modules.

As another preferred embodiment, when the power conversion module only needs to be connected in parallel with one equalized power conversion module group for voltage equalization, the first end and the second end of the power conversion module are the same port, and the first end of the power conversion module is connected in parallel with the voltage equalization port of the power conversion module group.

In practical application, if a power conversion module only needs to be connected in parallel with a voltage-sharing power conversion module group for voltage sharing, at this time, the first end and the second end of the power conversion module can be set to be the same end, and the first end of the power conversion module is only connected in parallel with the voltage-sharing port of the power conversion module group, so that the purpose of voltage sharing of the power conversion module and the voltage-sharing power conversion module group can be achieved.

Obviously, the technical scheme provided by the embodiment can relatively simplify the circuit complexity of the voltage equalizing device.

Based on the above embodiments, this embodiment further describes and optimizes the technical solution, and as a preferred implementation, the power conversion module includes a single power conversion unit and/or a plurality of power conversion units after voltage equalization.

In this embodiment, the power conversion module disposed inside the voltage equalizing device may be a single power conversion unit, may be multiple power conversion units after voltage equalization, or may be a combination of a single power conversion unit and multiple power conversion units after voltage equalization, so that the application range of the voltage equalizing device in practical use may be further widened.

Based on the above embodiments, the present embodiment further describes and optimizes the technical solution, and as a preferred implementation, the power conversion module has at least one transformer.

In practical applications, at least one transformer is disposed in the power conversion module, such as: the power conversion module can be set to any one circuit topology of an LLC resonant circuit, a CLLC resonant circuit, a CLL resonant circuit, an LCC resonant circuit, a CLLLC resonant circuit, a DAB circuit, a phase-shifted full-bridge circuit, a forward circuit, a flyback circuit or a push-pull circuit, or the power conversion module can also be set to any one circuit topology of an LLC resonant circuit, a CLLC resonant circuit, a CLL resonant circuit, an LCC resonant circuit, a CLLLC resonant circuit, a DAB circuit, a phase-shifted full-bridge circuit, a forward circuit, a flyback circuit or a push-pull circuitThe source transformation module is set as a variation or a combination circuit of the circuit module, as long as the actual application purpose can be achieved, and is not described in detail herein. Referring to fig. 7, fig. 7 is a block diagram of an LLC resonant circuit with two output ports. In the circuit diagram shown in FIG. 7, V₀₁Representing a first output port, V, of a transformer in a power conversion module₀₂Representing a second output port of the transformer in the power conversion module.

Obviously, the technical scheme provided by the embodiment can make the setting mode of the power conversion module more flexible and diversified.

Based on the above embodiments, this embodiment further describes and optimizes the technical solution, and as a preferred implementation, the voltages of the ports of the N power conversion modules are the same.

Utilize the voltage-sharing device that this application provided both can carry out the voltage-sharing to N power conversion module that output voltage equals, also can carry out the voltage-sharing to N power conversion module of output voltage proportional. Specifically, if the voltage-sharing device provided by the present application is needed to share the voltage of N power conversion modules with equal output voltages, the voltage at each port of the N power conversion modules can be set to be the same.

Or, as another preferred embodiment, the voltages of the ports of the N power conversion modules are set according to a preset ratio.

If the voltage-sharing device provided by the application is needed to share the voltage of the N power conversion modules with proportional output voltages, the voltage of each port of the N power conversion modules can be set according to the preset proportion. Referring to fig. 8, fig. 8 is a structural diagram of voltage-sharing connection between dc output ports of 3 power conversion modules. Specifically, in the circuit structure shown in fig. 8, the voltages of the first output port and the second output port of the first power conversion module in the 3 power conversion modules are respectively 1v₀And 3v₀The voltages of the first output port and the second output port of the second power conversion module are respectively 3v₀And 2v₀First output of the third power conversion moduleThe voltage of the port and the second output port is 2v respectively₀And 1v₀(wherein, v₀In assumed units of output port voltage). At this time, the first output port of the first power conversion module and the second output port of the third power conversion module are connected in parallel, the first output port of the second power conversion module and the second output port of the first power conversion module are connected in parallel, and the first output port of the third power conversion module and the second output port of the second power conversion module are connected in parallel, so that voltage sharing of the three power conversion modules can be realized.

Referring to fig. 9, fig. 9 is a structural diagram of voltage-sharing connection between winding ports of 3 power conversion modules. Specifically, in the circuit structure shown in fig. 9, the voltages of the first winding port and the second winding port of the first power conversion module in the 3 power conversion modules are respectively 1v₀And 3v₀The voltages of the first winding port and the second winding port of the second power conversion module are respectively 3v₀And 2v₀The voltages of the first winding port and the second winding port of the third power conversion module are respectively 2v₀And 1v₀(wherein, v₀In assumed units of winding port voltage). At this time, the voltage-sharing of the three power conversion modules can be realized by connecting the first winding port of the first power conversion module and the second winding port of the third power conversion module in parallel, connecting the first winding port of the second power conversion module and the second winding port of the first power conversion module in parallel, and connecting the first winding port of the third power conversion module and the second winding port of the second power conversion module in parallel. Of course, in practical application, the port voltage of the power conversion module may also be set according to other proportions based on the same principle, which is not described in detail herein.

Obviously, through the technical scheme provided by the embodiment, the voltage equalizing device can achieve the purpose of equalizing the voltage of the N power supply conversion modules.

Based on the foregoing embodiments, this embodiment further describes and optimizes the technical solution, and as a preferred implementation, if the power supplies of the N power conversion modules are direct currents, the control signals of the N power conversion modules are independent of each other.

If the power supply of the N power conversion modules is direct current, the control signals of the power conversion modules are independent and can be independently controlled. It can be understood that when each power conversion module in the voltage equalizing device is individually controlled, in addition to increasing flexibility in controlling the power conversion module, the output voltage ripple of the voltage equalizing device and the current ripple flowing through the output capacitor can be reduced by performing phase-staggered control on the power conversion modules.

Referring to fig. 10 and 11, fig. 10 is a schematic diagram of a voltage equalizing device provided with 4 power conversion modules, each power conversion module having a control signal. Fig. 11 is a diagram illustrating the result of the control signal interleaving performed by the 4 power conversion modules shown in fig. 10. Phase1 represents a control signal of the first power conversion module, Phase2 represents a control signal of the second power conversion module, Phase3 represents a control signal of the third power conversion module, and Phase4 represents a control signal of the fourth power conversion module. Phase1 leads Phase2 by 45 °, Phase2 leads Phase3 by 45 °, and Phase3 leads Phase4 by 45 °.

Of course, the staggered form and angle of the power conversion module can be selected in practical application. Such as: phase1 can be selected to lead Phase2 by 20 °, Phase2 by 30 °, Phase3 by 40 °; phase1 may be selected to lead Phase3 by 20, Phase3 by 2 and Phase2 by 4 by 40.

Based on the above embodiments, this embodiment further describes and optimizes the technical solution, and as a preferred implementation, the parallel ports can be combined in series and parallel.

In this embodiment, in order to enable the voltage equalizing device provided in the present application to flexibly adjust the input voltage or the output voltage thereof, the parallel power conversion modules may be freely combined in series and parallel.

Referring to fig. 12 and 13, fig. 12 is a structural diagram of an input port of the entire voltage-sharing device formed by connecting three parallel port groups in series, and fig. 13 is a structural diagram of an output port of the entire voltage-sharing device formed by connecting three parallel port groups in series. Of course, after the parallel ports are connected in series and parallel, the parallel ports may be used as input ports or output ports of the whole voltage equalizing device, or may not be used as ports for power transmission. Referring to fig. 14, fig. 14 is a schematic connection diagram of 3 power conversion modules when the parallel voltage sharing port is not used for power transfer.

In practical applications, the number of input ports or output ports of the power conversion module may be 2 or more. When the power conversion module has a plurality of input ports or output ports, the plurality of input ports or output ports of the power conversion module can be connected in parallel to form 2 groups of equivalent input ports or output ports to carry out voltage sharing on the plurality of power conversion modules; or selecting 2 input ports or output ports in the power conversion module to carry out voltage sharing with other power conversion modules, and then carrying out series-parallel connection combination on the voltage-sharing input ports or output ports and other input ports or output ports to achieve the required input or output voltage specification. Referring to fig. 15, fig. 15 is a connection structure diagram when 6 output ports of two power conversion modules are connected in a voltage-sharing manner.

Correspondingly, the embodiment of the invention also discloses a power supply conversion system which comprises the voltage-sharing device of the power supply conversion module.

The power conversion system provided by the embodiment of the invention has the beneficial effects of the voltage equalizing device of the power conversion module disclosed in the invention.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Furthermore, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly limited by the phrase "comprising one … …," without precluding the presence of additional like elements in the process, method, article, or apparatus that comprises the elements.

The voltage-sharing device of the power conversion module and the power conversion system provided by the invention are described in detail, a specific example is applied in the text to explain the principle and the implementation of the invention, and the description of the above embodiment is only used to help understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.