CN212969478U

CN212969478U - Bridge arm module, power conversion circuit and power conversion system

Info

Publication number: CN212969478U
Application number: CN202020649774.8U
Authority: CN
Inventors: 陈鹏; 徐清清; 李顺
Original assignee: Sungrow Power Supply Co Ltd
Current assignee: Sungrow Power Supply Co Ltd
Priority date: 2020-04-26
Filing date: 2020-04-26
Publication date: 2021-04-13
Anticipated expiration: 2030-04-26

Abstract

The present disclosure relates to the field of power electronics technologies, and in particular, to a bridge arm module, a power conversion circuit, and a power conversion system. The topological structure of the bridge arm module comprises a plurality of power devices; moreover, each power device is respectively packaged in at least two packaging modules; compared with the prior art, the topological structure in the bridge arm module is not required to be divided into parallel connection and equal division according to the circuit structure or the power, so that the power of the packaging module can be utilized to the maximum when the bridge arm module packages a plurality of power devices, the problem of margin design does not exist, and the problem of difficulty in margin design when a plurality of packaging modules are connected in parallel in the prior art is solved. In addition, each packaging module adopts at least two different packaging modes, so that the wiring difficulty in design is reduced and parasitic parameters among the packaging modules are reduced.

Description

Bridge arm module, power conversion circuit and power conversion system

Technical Field

The utility model relates to a power electronics technical field especially relates to a bridge arm module, power conversion circuit and power conversion system.

Background

At present, in consideration of the cost and the volume of the inverter unit, when the inverter unit is designed, the inverter unit is generally constructed by using a packaged power module, i.e., a packaging module.

When the constructed inverter unit is an inverter unit with higher power, the inverter unit is limited by the packaging limitation of the packaging modules in the prior art, and the inverter unit needs to be formed by connecting a plurality of packaging modules in parallel, namely, the higher power of the inverter unit is shared by the plurality of packaging modules.

However, when the inverter unit is designed, complete equalization of a circuit or power is difficult to achieve, so that parallel-connected packaging modules or too large margin is caused, waste is caused, or the design is difficult when the margin is insufficient; moreover, because the packaging modes of the packaging modules in the prior art are consistent, the difficulty in designing the wiring is high and the stray inductance of each packaging module is high.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a bridge arm module, power conversion circuit and power conversion system to surplus design difficulty, the design is walked the great and great problem of the stray inductance of self when solving among the prior art when a plurality of encapsulation modules are parallelly connected.

In order to achieve the above object, the embodiment of the present invention provides the following technical solutions:

a first aspect of the present application provides a bridge arm module, wherein a topology structure of the bridge arm module includes a plurality of power devices;

each power device is respectively packaged in at least two packaging modules;

each packaging module adopts at least two different packaging modes.

Optionally, the topology structure of the bridge arm module includes: a single bridge arm;

the single bridge arm comprises a plurality of power devices which are respectively packaged in at least two packaging modules with different packaging modes.

Optionally, the topology structure of the bridge arm module includes: the first bridge arm and the second bridge arm are connected in parallel;

the first bridge arm comprises a single power device, and the second bridge arm comprises a plurality of power devices;

and the first bridge arm and the second bridge arm are respectively packaged in at least two packaging modules with different packaging modes.

Optionally, the topology structure of the bridge arm module is as follows: any one of full-bridge topology, half-bridge topology, three-phase four-leg inverter topology, boost topology, buck topology and buck-boost topology.

Optionally, the different packaging manners include: the encapsulation material is different and/or the encapsulation structure is different.

Optionally, the packaging material includes: an encapsulating material with an auxiliary heat dissipating portion, and an encapsulating material without an auxiliary heat dissipating portion.

Optionally, the auxiliary heat dissipation part is: a copper substrate or an aluminum substrate.

Optionally, each of the encapsulation modules includes: at least one first package module and at least one second package module; wherein:

the heat productivity of the first packaging module is larger than the heat dissipation capacity of the second packaging module.

Optionally, the packaging material of the first packaging module is a packaging material with an auxiliary heat dissipation portion; the packaging material of the second packaging module is the packaging material without the auxiliary heat dissipation part.

Optionally, the power device packaged in the first packaging module is a power device with high-frequency commutation, and the power device packaged in the second packaging module is a power device without high-frequency commutation.

Optionally, the power device packaged in the first packaging module is a high-frequency power device, and the power device packaged in the second packaging module is a power-frequency power device.

Optionally, the power device packaged in the first packaging module is a power device through which active current flows, and the power device packaged in the second packaging module is a power device through which reactive current flows.

Optionally, if the topology structure of the bridge arm module is an ANPC three-level topology structure, the power device packaged in the first package module includes: four switching tubes and anti-parallel diodes thereof, wherein the four switching tubes are connected with the direct current side;

the power device packaged in the second package module includes: two switching tubes connected with the AC side and anti-parallel diodes thereof.

Optionally, the anti-parallel diode is: a body diode of the corresponding switch tube; alternatively, the first and second electrodes may be,

the anti-parallel diode is: the external diodes are connected with the corresponding switch tubes in reverse parallel; and, the switch tube is: a switch tube with a body diode, or a switch tube without a body diode.

Optionally, if the topology structure of the bridge arm module is an NPC three-level topology structure, the power device packaged in the first package module includes: two switching tubes connected with the positive electrode and the negative electrode of the direct current side, anti-parallel diodes of the switching tubes, and two diodes connected with the midpoint of the direct current side;

Optionally, if the topology structure of the bridge arm module is an ANPC three-level topology structure, the power device packaged in the first package module includes: the two switching tubes are connected with the positive electrode and the negative electrode of the direct current side, the two switching tubes are connected with the alternating current side, and the anti-parallel diodes of the two switching tubes are connected with the midpoint of the direct current side;

the power device packaged in the second package module includes: the reverse parallel diodes of the two switch tubes connected with the positive electrode and the negative electrode of the direct current side, the reverse parallel diodes of the two switch tubes connected with the alternating current side and the two switch tubes connected with the midpoint of the direct current side.

Optionally, the anti-parallel diode is: the external diodes are connected with the corresponding switch tubes in reverse parallel;

the switch tube is as follows: a switch tube with a body diode, or a switch tube without a body diode.

The second aspect of the present application also provides a power conversion circuit, including: the bridge arm comprises a first bridge arm module and a second bridge arm module which are connected in series; wherein:

the calorific value of the first bridge arm module is larger than that of the second bridge arm module;

and the first bridge arm module and the second bridge arm module are packaged in different modes.

Optionally, the packaging material of the first bridge arm module is a packaging material with an auxiliary heat dissipation part; and the packaging material of the second bridge arm module is the packaging material without the auxiliary heat dissipation part.

Optionally, each of the first bridge arm module and the second bridge arm module includes a single power device.

Optionally, at least one of the first bridge arm module and the second bridge arm module is: a bridge arm module as claimed in any one of the first aspect of the present application.

The third aspect of the present application further provides a power conversion system, including: a bridge arm module as claimed in any one of the first aspects of the present application, or a power conversion circuit as claimed in any one of the second aspects of the present application.

According to the above technical scheme, the utility model provides a bridge arm module. The topological structure of the bridge arm module comprises a plurality of power devices; moreover, each power device is respectively packaged in at least two packaging modules; compared with the prior art, the topological structure in the bridge arm module is not required to be divided into parallel connection and equal division according to the circuit structure or the power, so that the power of the packaging module can be utilized to the maximum when the bridge arm module packages a plurality of power devices, the problem of margin design does not exist, and the problem of difficulty in margin design when a plurality of packaging modules are connected in parallel in the prior art is solved. In addition, each packaging module adopts at least two different packaging modes, so that the wiring difficulty in design is reduced and parasitic parameters among the packaging modules are reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be 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. 1a and fig. 1b are schematic diagrams of two kinds of packages of each bridge arm in a bridge arm module provided in an embodiment of the present application;

FIGS. 2a and 2b are schematic views of a package with a copper substrate;

FIGS. 2c and 2d are schematic views of a package without a copper substrate;

fig. 3 is a schematic structural diagram of an ANPC three-level circuit according to an embodiment of the present disclosure;

4 a-4 d are schematic diagrams of four operation modes of the ANPC three-level circuit when the output voltage at the AC output side of the ANPC three-level circuit provided by the embodiment of the application is in a positive half period;

fig. 5a, fig. 5b, and fig. 6 are schematic diagrams of three packaging schemes of a plurality of power devices in each bridge arm of a bridge arm module according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In this application, 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 listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

In order to solve the problems that in the prior art, when a plurality of packaged modules are connected in parallel, the margin design is difficult, the design wiring difficulty is high, and the stray inductance of the packaged modules is high, the embodiment of the application provides a bridge arm module, and the topology structure of the bridge arm module is not limited, such as any one of a full-bridge topology, a half-bridge topology, a three-phase four-bridge arm inversion topology, a boosting topology, a step-down topology, and a step-up and step-down topology.

The topological structure of the bridge arm module comprises a plurality of power devices. As shown in fig. 1a, in the bridge arm module 10, each power device is packaged in at least two packaging modules 20, and each packaging module 20 adopts at least two different packaging methods.

In practical application, the bridge arm module 10 may include only a single bridge arm, where the single bridge arm includes a plurality of power devices, and the power devices are respectively packaged in at least two packaging modules with different packaging methods. The bridge arm module 10 may also include a first bridge arm and a second bridge arm connected in parallel; the first bridge arm comprises a single power device, such as a bypass device and the like; the second bridge arm comprises a plurality of power devices, such as a boost topology, a buck topology or a buck-boost topology; the first bridge arm and the second bridge arm are respectively packaged in at least two packaging modules with different packaging modes.

Moreover, each encapsulation module 20 at least adopts two different encapsulation methods, which may specifically be: the packaging materials of the packaging modules 20 are different, for example, there are packaging modules 20 using the packaging material with the auxiliary heat dissipation portion, and there are packaging modules 20 using the packaging material without the auxiliary heat dissipation portion; the auxiliary heat dissipation portion may be a copper substrate or an aluminum substrate, which is not limited herein. Each encapsulation module 20 adopts at least two different encapsulation methods, which may be: the packaging materials of the packaging modules 20 are the same, but the packaging structures of the packaging modules 20 are different; the packaging material and the packaging structure of each packaging module 20 may be different; depending on the specific application environment, are all within the scope of the present application.

For example, in practical applications, if a plurality of power devices included in the bridge arm module 10 are packaged in two package modules 20, the two package modules 20 may adopt a package manner with a copper substrate as shown in fig. 2a and 2b, or a package manner without a copper substrate as shown in fig. 2c or 2 d.

However, in consideration of reasonable utilization of the two packaging methods, as shown in fig. 1b, the packaging module with a larger heat value, i.e., the first packaging module 21, is usually packaged in a packaging method with a copper substrate, so that the heat dissipation capability of the first packaging module is enhanced, and the first packaging module can dissipate heat quickly to ensure normal operation of the first packaging module; moreover, the second package module 22, which is a package module with a smaller heat value, is usually packaged in a package manner without a copper substrate, so that the package cost is reduced and the package volume is correspondingly reduced on the premise of ensuring the normal operation of the package module.

In practical application, in the bridge arm module 10, the power devices may be divided into two types, one type is a power device with high frequency commutation, and the other type is a power device without high frequency commutation, and the heat value of the power device with high frequency commutation is larger than that of the power device without high frequency commutation, so that the power device packaged in the first packaging module 21 is a power device with high frequency commutation, such as a high frequency power device; the power devices packaged in the second packaging module 22 are power devices without high frequency commutation, such as power frequency power devices.

The above is only one packaging scheme of a plurality of power devices in the bridge arm module 10, and in the packaging process of the bridge arm module 10, another packaging scheme of a plurality of power devices may also be actually adopted, specifically:

in the bridge arm module 10, the power devices are similarly classified into two types, but one type is a power device through which an active current flows, and the other type is a power device through which a reactive current flows, and the amount of heat generated by the power device through which the active current flows is larger than the amount of heat generated by the power device through which the reactive current flows, and therefore, the power device packaged in the first packaging module 21 is a power device through which the active current flows, and the power device packaged in the second packaging module 22 is a power device through which the reactive current flows.

The two packaging schemes of the power devices are only the preferable schemes of the packaging schemes of the power devices, and the circuit power devices which work for a long time and have large heat productivity are placed in the module with the copper substrate due to the fact that the circuit power devices are divided according to the functions of the devices, so that the heat dissipation advantage is well played. In practical application, the packaging schemes of the plurality of power devices include, but are not limited to, the two packaging schemes, which are not specifically limited herein, and may be selected according to specific situations, and the method is within the protection scope of the present application as long as the method packages all the power devices in the topology of the bridge arm module 10 into a plurality of packaging modules respectively by longitudinally splitting all the power devices in the topology of the bridge arm module 10, and then connects the packaging modules according to the topology structure, so that each packaging module meets the requirement of the packaging scale limitation.

According to the above scheme, each power device of the bridge arm module 10 provided by the present application is respectively packaged in at least two packaging modules 20, that is, the packaging modules after longitudinal splitting are connected according to a topological structure, instead of the scheme of parallel connection of the packaging modules after parallel splitting in the prior art, so that the topological structure of the bridge arm module 10 does not need to be equally divided according to a circuit structure or power, and therefore, when a plurality of power devices in the bridge arm module 10 are packaged, the power of the packaging modules 20 can be maximally utilized, and the problem of margin design does not exist, thereby solving the problem of difficulty in margin design when a plurality of packaging modules 20 are connected in parallel in the prior art. In addition, when the plurality of power devices in each bridge arm module 10 are packaged, each packaged module 20 of the bridge arm module 10 may be composed of power devices of different types, so that the power of the power devices can be utilized to the maximum extent, the size of the power devices is optimal, and no waste is caused.

In addition, each packaging module in each bridge arm adopts at least two different packaging modes, so that the wiring design difficulty is reduced, and parasitic parameters among the packaging modules are reduced. In addition, the difference of the packaging modes is more beneficial to the differentiation of a plurality of packaging modules 20, so that the bus bar layout is more convenient and is not limited by the consistency of the positions of the same packaging pins.

The above embodiment describes in detail a packaging scheme of a plurality of power devices included in the topology structure of the bridge arm module 10, and the embodiment further describes the topology structure of the bridge arm module 10 as an example of an ANPC three-level topology structure.

The ANPC three-level circuit is a relatively mature conversion circuit in the prior art, and generally has a structure as shown in fig. 3, and specifically includes: the circuit comprises a first switch tube Q1, a first anti-parallel diode D1, a second switch tube Q2, a second anti-parallel diode D2, a third switch tube Q3, a third anti-parallel diode D3, a fourth switch tube Q4, a fourth anti-parallel diode D4, a fifth switch tube Q5, a fifth anti-parallel diode D5, a sixth switch tube Q6 and a sixth anti-parallel diode D6.

In the ANPC three-level circuit, an input end of a first switching tube Q1 is used as a direct-current side positive pole P + of the ANPC three-level circuit, an output end of a first switching tube Q1 is connected with an input end of a second switching tube Q2, an output end of a second switching tube Q2 is connected with an input end of a third switching tube Q3, an output end of a third switching tube Q3 is connected with an input end of a fourth switching tube Q4, and an output end of a fourth switching tube Q4 is used as a direct-current side negative pole N-; an input end of the fifth switching tube Q5 is connected with an output end of the first switching tube Q1, an output end of the fifth switching tube Q5 is connected with an input end of the sixth switching tube Q6, an output end of the sixth switching tube Q6 is connected with an input end of the fourth switching tube Q4, a connection point of an output end of the second switching tube Q2 and an input end of the third switching tube Q3 is used as a direct current side middle point Ne of the ANPC three-level circuit, and a connection point of an output end of the fifth switching tube Q5 and an input end of the sixth switching tube Q6 is used as an alternating current side AC of the ANPC three-level circuit.

The first anti-parallel diode D1 is connected in parallel with two ends of the first switch tube Q1 in an opposite direction, the second anti-parallel diode D2 is connected in parallel with two ends of the second switch tube Q2 in an opposite direction, the third anti-parallel diode D3 is connected in parallel with two ends of the third switch tube Q3 in an opposite direction, and the fourth anti-parallel diode D4 is connected in parallel with two ends of the fourth switch tube Q4 in an opposite direction.

It should be noted that, when each switching tube in fig. 3 is a switching tube with a body diode, each backward diode is the body diode of each switching tube; when each anti-parallel diode in fig. 3 is an external diode, each switching tube may be a switching tube with a body diode (the body diode is not shown in the figure), or a switching tube without a body diode, which is not specifically limited herein and is within the scope of the present application as the case may be.

When the ANPC three-level circuit operates in a positive half cycle of the voltage output from the AC output side, as can be seen from the control method of the ANPC three-level circuit, if the voltage output from the AC side of the ANPC three-level circuit is a positive voltage and the current is a positive current, as shown in fig. 4a, the first switching tube Q1 and the fifth switching tube Q5 are turned on, the current flows in from P +, then flows through the first switching tube Q1 and the fifth switching tube Q5, and then flows out from the AC.

If the voltage output by the AC side of the ANPC three-level circuit is a positive voltage and the current is zero, the second anti-parallel diode D2 and the fifth switch Q5 are turned on as shown in fig. 4b, and the current flows in from Ne, then flows through the second anti-parallel diode D2 and the fifth switch Q5, and then flows out from AC.

If the voltage output by the AC side of the ANPC three-level circuit is zero and the current is negative, the fifth anti-parallel diode D5 and the first anti-parallel diode D1 are turned on as shown in fig. 4c, and the current flows from the AC, then flows through the fifth anti-parallel diode D5 and the first anti-parallel diode D1, and then flows out from the P +.

When the voltage output from the AC side of the ANPC three-level circuit is a positive voltage and the current is a negative current, the fifth anti-parallel diode D5 and the second switch Q2 are turned on as shown in fig. 4D, and the current flows in from the AC, then flows through the fifth anti-parallel diode D5 and the second switch Q2, and then flows out from Ne.

When the ANPC three-level circuit operates in the negative half-cycle of the voltage output from the ac output side, the above process is similar to that described above, and the description thereof is omitted here.

As for the first packaging scheme of the plurality of power devices in the bridge arm module 10 in the above embodiment, as can be seen from the above description, when the output voltage at the ac output side is in the positive half cycle, as shown in fig. 5a, the power devices with high frequency commutation are the first switching tube Q1 and the first anti-parallel diode D1, and the second switching tube Q2 and the second anti-parallel diode D2, and the power devices without high frequency commutation are the fifth switching tube Q5 and the fifth anti-parallel diode D5; when the output voltage on the alternating current side is in a negative half period, as shown in fig. 5a, the power devices with high-frequency commutation are the third switch tube Q3 and the third anti-parallel diode D3, and the fourth switch tube Q4 and the fourth anti-parallel diode D4, and the power devices without high-frequency commutation are the sixth switch tube Q6 and the sixth anti-parallel diode D6.

It should be noted that, in practical application, since the first switch tube Q1 in fig. 5a cannot accurately refer to the switch tube at the corresponding position in the ANPC three-level circuit, the first switch tube Q1 and the first anti-parallel diode D1, the second switch tube Q2 and the second anti-parallel diode D2, the third switch tube Q3 and the third anti-parallel diode D3, and the fourth switch tube Q4 and the fourth anti-parallel diode D4 in fig. 5a are described as follows: four switching tubes and parallel diodes thereof, wherein the four switching tubes are connected with the direct current side; and the fifth switching tube Q5 and the fifth anti-parallel diode D5 and the sixth switching tube Q6 and the sixth anti-parallel diode D6 are described as: two switching tubes connected with the AC side and anti-parallel diodes thereof.

In summary, as shown by two dashed boxes in fig. 5a, the power device packaged in the first package module 21 with a large heat generation amount includes: four switching tubes and anti-parallel diodes thereof, wherein the four switching tubes are connected with the direct current side; the power device packaged in the second package module 22 having a smaller heat generation amount includes: two switching tubes connected with the AC side and anti-parallel diodes thereof.

Similarly, if the topology of each bridge arm is the NPC three-level topology shown in fig. 5b, the power device packaged in the first package module 21 with a large heat value includes: two switching tubes (Q1 and Q4) connected with the positive pole and the negative pole of the direct current side and anti-parallel diodes thereof, and two diodes (D2 and D3) connected with the middle point of the direct current side; the power device packaged in the second package module 22 having a smaller heat generation amount includes: two switching tubes (Q2 and Q3) and their anti-parallel diodes are connected with the AC side.

It should be noted that, for the first packaging scheme of the multiple power devices in the bridge arm module 10 in the foregoing embodiment, taking the ANPC three-level topology shown in fig. 5a as an example, if each anti-parallel diode is a body diode of each switching tube, each switching tube is a switching tube with a body diode; if each anti-parallel diode is an external diode which is connected with the corresponding switch tube in reverse parallel, each switch tube is a switch tube with a diode or a switch tube without a body diode.

As for the second packaging scheme of the plurality of power devices in the bridge arm module 10 in the above embodiment, as can be seen from the above description, when the output voltage on the ac output side is in the positive half cycle, as shown in fig. 6, the power devices through which the active current flows are the first switch tube Q1, the second anti-parallel diode D2 and the fifth switch tube Q5, and the power devices through which the reactive current flows are the first anti-parallel diode D1, the second switch tube Q2 and the fifth anti-parallel diode D5; when the output voltage on the ac side is in the negative half period, as shown in fig. 6, the power devices through which the active current flows are the third anti-parallel diode D3, the fourth switch Q4, and the sixth switch Q6, and the power devices through which the reactive current flows are the third switch Q3, the fourth anti-parallel diode D4, and the sixth anti-parallel diode D6.

It should be noted that, in practical applications, since the first switch tube Q1 in fig. 6 cannot accurately refer to the switch tube at the corresponding position in the ANPC three-level circuit, the first switch tube Q1 and the fourth switch tube Q4 in fig. 6 are described as follows: two switching tubes connected with the positive electrode and the negative electrode on the direct current side; the second anti-parallel diode D2 and the third anti-parallel diode D3 in fig. 6 are depicted as: the anti-parallel diodes of the two switching tubes are connected with the midpoint of the direct current side; the fifth switching tube Q5 and the sixth switching tube Q6 in fig. 6 are described as follows: two switching tubes connected to the AC side; the first anti-parallel diode D1 and the fourth anti-parallel diode D4 in fig. 6 are depicted as: the anti-parallel diodes of the two switching tubes are connected with the positive electrode and the negative electrode of the direct current side; the fifth anti-parallel diode D5 and the sixth anti-parallel diode D6 in fig. 6 are described as: anti-parallel diodes of two switching tubes connected with the alternating current side; the second switching tube Q2 and the third switching tube Q3 in fig. 6 are described as follows: and the two switching tubes are connected with the middle point of the direct current side.

As described above, as shown by two dashed boxes in fig. 6, the power device packaged in the first package module 21 having a large heat generation amount includes: the two switching tubes are connected with the positive electrode and the negative electrode of the direct current side, the two switching tubes are connected with the alternating current side, and the anti-parallel diodes of the two switching tubes are connected with the midpoint of the direct current side; the power device packaged in the second package module 22 having a smaller heat generation amount includes: the reverse parallel diodes of the two switch tubes connected with the positive electrode and the negative electrode of the direct current side, the reverse parallel diodes of the two switch tubes connected with the alternating current side and the two switch tubes connected with the midpoint of the direct current side.

It should be noted that, for the second packaging scheme of the multiple power devices in the bridge arm module 10 in the foregoing embodiment, each anti-parallel diode in fig. 6 is an external diode connected in inverse parallel with each switching tube, and each switching tube may be a switching tube with a diode (as shown in fig. 6), or a switching tube without a body diode (not shown), which may be specific, and are not described herein again.

Optionally, all the switch tubes may be MOS transistors or IGBTs, which are not specifically limited herein and are within the protection scope of the present application as the case may be.

As can be seen from the above, one phase bridge arm of the three-phase inverter provided in this embodiment is composed of one inverter unit, each inverter unit at least includes 2 longitudinally split power modules, and the power modules in each inverter unit are packaged differently, and at least 1 is a module without a copper substrate. In practical application, a circuit connected with the positive electrode and the negative electrode (P + and N-) of the direct current bus can be placed in a module with a copper substrate, high-frequency commutation also exists in the circuit, a circuit connected with the alternating current side is placed in another module, and the circuit does not have high-frequency commutation; alternatively, the die through which the active current flows may be placed in a module having a copper substrate, and the die through which the reactive current flows may be placed in a module having no copper substrate. The heat productivity of the chip in the module with the copper substrate is larger than that of the chip in the module without the copper substrate, and the heat dissipation of a power device with large heat productivity is facilitated.

For bridge arm modules with other topological structures, different packaging materials can be packaged according to different heat values, and specific principles are not repeated one by one and are all within the protection scope of the application.

The utility model discloses another embodiment still provides a power conversion circuit, include: the bridge arm comprises a first bridge arm module and a second bridge arm module which are connected in series; wherein:

the calorific value of the first bridge arm module is larger than that of the second bridge arm module; the first bridge arm module and the second bridge arm module are packaged in different manners, specifically, the packaging structures may be different, or the packaging materials may be different, for example, the packaging material of the first bridge arm module is a packaging material with an auxiliary heat dissipation portion; the packaging material of the second bridge arm module is the packaging material without the auxiliary heat dissipation part.

The two bridge arm modules are packaged by different packaging materials according to different heating values, and specific principles of the two bridge arm modules can be referred to the above embodiments, which are not described in detail herein and are all within the protection scope of the present application.

It should be noted that, in the power conversion circuit, both the first bridge arm module and the second bridge arm module thereof may include a single power device, or at least one of the first bridge arm module and the second bridge arm module thereof may be the bridge arm module described in any of the above embodiments, and the specific principle is not described herein again.

The utility model discloses another embodiment still provides a power conversion system, and its main circuit includes: the bridge arm module according to any of the above embodiments, or the power conversion circuit according to the above embodiments.

The specific structures and principles of the bridge arm module and the power conversion circuit can be found in the above embodiments, and are not described in detail here.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, the system or system embodiments are substantially similar to the method embodiments and therefore are described in a relatively simple manner, and reference may be made to some of the descriptions of the method embodiments for related points. The above-described system and system embodiments are only illustrative, wherein the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A bridge arm module is characterized in that a topological structure of the bridge arm module comprises a plurality of power devices;

each power device is respectively packaged in at least two packaging modules;

each packaging module adopts at least two different packaging modes.

2. The bridge leg module of claim 1, wherein the topology of the bridge leg module comprises: a single bridge arm;

3. The bridge leg module of claim 1, wherein the topology of the bridge leg module comprises: the first bridge arm and the second bridge arm are connected in parallel;

4. The bridge leg module of claim 1, wherein the topology of the bridge leg module is: any one of full-bridge topology, half-bridge topology, three-phase four-leg inverter topology, boost topology, buck topology and buck-boost topology.

5. The bridge arm module of any one of claims 1 to 4, wherein the different packaging modes comprise: the encapsulation material is different and/or the encapsulation structure is different.

6. The bridge arm module of claim 5, wherein the encapsulating material comprises: an encapsulating material with an auxiliary heat dissipating portion, and an encapsulating material without an auxiliary heat dissipating portion.

7. The bridge arm module of claim 6, wherein the auxiliary heat sink portion is: a copper substrate or an aluminum substrate.

8. The bridge leg module of any one of claims 1-4, wherein each of the encapsulated modules comprises: at least one first package module and at least one second package module; wherein:

9. The bridge arm module of claim 8, wherein the encapsulant of the first encapsulant module is an encapsulant with an auxiliary heat dissipation portion; the packaging material of the second packaging module is the packaging material without the auxiliary heat dissipation part.

10. The bridge leg module of claim 8, wherein the power devices packaged in the first packaged module are power devices with high frequency commutation, and the power devices packaged in the second packaged module are power devices without high frequency commutation.

11. The bridge arm module of claim 10, wherein the power devices packaged in the first packaging module are high-frequency power devices, and the power devices packaged in the second packaging module are power frequency power devices.

12. The bridge arm module of claim 8, wherein the power devices packaged in the first packaged module are power devices through which active current flows, and the power devices packaged in the second packaged module are power devices through which reactive current flows.

13. The bridge leg module of claim 10, wherein if the topology of the bridge leg module is an ANPC three-level topology, the power devices packaged in the first packaged module comprise: four switching tubes and anti-parallel diodes thereof, wherein the four switching tubes are connected with the direct current side;

14. The bridge arm module of claim 13, wherein the anti-parallel diodes are: a body diode of the corresponding switch tube; alternatively, the first and second electrodes may be,

15. The bridge leg module of claim 10, wherein if the topology of the bridge leg module is an NPC three-level topology, the power devices packaged in the first packaged module comprise: two switching tubes connected with the positive electrode and the negative electrode of the direct current side, anti-parallel diodes of the switching tubes, and two diodes connected with the midpoint of the direct current side;

16. The bridge arm module of claim 15, wherein the anti-parallel diodes are: a body diode of the corresponding switch tube; alternatively, the first and second electrodes may be,

17. The bridge leg module of claim 12, wherein if the topology of the bridge leg module is an ANPC three-level topology, the power devices packaged in the first packaged module comprise: the two switching tubes are connected with the positive electrode and the negative electrode of the direct current side, the two switching tubes are connected with the alternating current side, and the anti-parallel diodes of the two switching tubes are connected with the midpoint of the direct current side;

18. The bridge arm module of claim 17, wherein the anti-parallel diodes are: the external diodes are connected with the corresponding switch tubes in reverse parallel;

19. A power conversion circuit, comprising: the bridge arm comprises a first bridge arm module and a second bridge arm module which are connected in series; wherein:

20. The power conversion circuit of claim 19, wherein the different packaging schemes comprise: the encapsulation material is different and/or the encapsulation structure is different.

21. The power conversion circuit according to claim 20, wherein the encapsulating material of the first leg module is an encapsulating material with an auxiliary heat dissipation portion; and the packaging material of the second bridge arm module is the packaging material without the auxiliary heat dissipation part.

22. The power conversion circuit of any of claims 19-21, wherein each of the first leg module and the second leg module comprises a single power device.

23. The power conversion circuit of any of claims 19-21, wherein at least one of the first leg module and the second leg module is: the bridge arm module of any one of claims 1 to 18.

24. A power conversion system, comprising: the bridge arm module of any one of claims 1 to 18, or the power conversion circuit of any one of claims 19 to 23.