Power converter and power conversion system

Abstract

The application discloses a power converter and a power conversion system, which comprise a heat dissipation substrate, a first insulating layer, at least one first type power device, at least one second type power device and a power device mounting substrate; the power device mounting substrate comprises a second insulating layer, a first metal layer corresponding to each power device and a second metal layer corresponding to each power device; the second insulating layer is provided with at least one via hole; the heat dissipation substrate, the first insulating layer, the second metal layer, the second insulating layer and the first metal layer are sequentially arranged from bottom to top; the first type power device and the second type power device are respectively arranged on the corresponding first metal layer; the second metal layer corresponding to each first type power device is electrically connected with the first metal layer corresponding to a target second type power device in the at least one second type power device through a target via hole in the at least one via hole; and the application can improve the mounting efficiency and ensure the heat dissipation uniformity of the heat dissipation substrate to each power device.

Description

Technical Field

[0001] This invention belongs to the field of power electronic converter technology, specifically relating to a power converter and a power conversion system. Background Technology

[0002] To better utilize the performance of power devices, efficient heat dissipation is essential. Parasitic capacitance between the power device and the heat sink is unavoidable. When the power device switches, current flows through this parasitic capacitance, returning to the circuit via the heat sink, thus forming a common-mode current that affects the entire system's operation. Third-generation wide-bandgap semiconductor devices offer excellent switching performance, with high speed and low loss, making them suitable for high-voltage and high-frequency applications. However, their faster switching speeds result in larger common-mode currents.

[0003] Typically, the common-mode current of power devices in high-frequency applications can be reduced or eliminated in the following two ways:

[0004] The first approach is to reduce the common-mode current by decreasing parasitic capacitance, bringing it to a level acceptable to the system. For example, increasing the distance between the power device and the heat sink can help, but this increases the thermal resistance of the power device, reducing its performance. Alternatively, a dielectric material with both low dielectric constant and low thermal resistance can be chosen, but cost may be a barrier.

[0005] The second method converts common-mode current into differential-mode current to minimize common-mode interference. Differential-mode current generates relatively less interference in the circuit and is easier to filter out. The core of this method is to create two parasitic capacitors in series between the power device and the heatsink. Then, the midpoint of these two series-connected parasitic capacitors is connected to a stable point (such as the positive or negative terminal supported by a capacitor in a half-bridge circuit, or the midpoint of a three-level voltage). In this way, the common-mode current generated by the switching action of the power device, flowing through the parasitic capacitors to ground, returns directly to the circuit, no longer forming a loop through the heatsink (ground), thus essentially eliminating the interference caused by common-mode current.

[0006] For example, Figure 1 This is a schematic diagram of a power converter based on related technologies, using a MOSFET chip as an example of a power device. Figure 1 As shown, the lower surface of power device Q1 (with drain D) is disposed on a first substrate S1 having a first insulating layer I1, and power device Q2 having a switching electrode (e.g., drain D) is disposed on a second substrate S2 having a second insulating layer I2. The second substrate S2 is disposed on the first substrate S1, and the first substrate S1 is disposed on a heat dissipation substrate 10, which is a voltage static point. Figure 1In this way, it is equivalent to connecting the midpoint of the two series parasitic capacitances of the drain of power device Q2 to ground to the drain of power device Q1. That is, power device Q1 only needs one layer of insulating medium, while power device Q2 needs two layers of insulating medium. In this way, the common-mode current of power device Q2 is suppressed.

[0007] However, in related technologies, different power devices correspond to different numbers or thicknesses of insulating media, which makes installation inconvenient and the heat dissipation substrate does not provide uniform heat dissipation for each power device. Summary of the Invention

[0008] The main objective of this invention is to provide a power converter and power conversion system to solve the problems in the prior art where different power devices correspond to different numbers or thicknesses of insulating media, resulting in inconvenient installation and uneven heat dissipation of each power device by the heat dissipation substrate.

[0009] To address the aforementioned problems, the present invention provides a power converter, characterized in that it includes a heat dissipation substrate, a first insulating layer, at least one first type of power device, at least one second type of power device, and a power device mounting substrate; wherein, the first type of power device is a power device including a switching electrode with a switching potential, and the second type of power device is a power device including a switching electrode without a switching potential.

[0010] The power device mounting substrate includes a second insulating layer, a first metal layer corresponding to each power device, and a second metal layer corresponding to each power device; the second insulating layer has at least one via.

[0011] The heat dissipation substrate, the first insulating layer, the second metal layer, the second insulating layer, and the first metal layer are arranged in the following order from bottom to top;

[0012] The first type of power device and the second type of power device are respectively disposed on the corresponding first metal layer;

[0013] The second metal layer corresponding to each of the first type of power devices is electrically connected to the first metal layer corresponding to at least one target second type of power device through at least one of the vias.

[0014] Furthermore, in the power converter described above, the target second type of power device is at least one second type of power device that is closest to the first type of power device;

[0015] The target via is the via between the target second type of power device and the first type of power device.

[0016] Furthermore, in the power converter described above, the power device mounting substrate includes a direct copper-clad (DBC) substrate.

[0017] Furthermore, in the power converter described above, the material of the first insulating layer includes ceramic, AlN, or SiN.

[0018] Furthermore, in the power converter described above, the material of the second insulating layer includes ceramic, AlN, or SiN.

[0019] Furthermore, in the power converter described above, the material of the first metal layer and / or the material of the second metal layer includes copper.

[0020] Furthermore, in the power converter described above, the thickness of the first insulating layer is greater than the thickness of the second insulating layer.

[0021] Furthermore, in the power converter described above, the first type of power device includes a first type of MOSFET chip or a first type of IGBT chip;

[0022] The drain of the first type of MOSFET chip is electrically connected to the first metal layer, and the drain of the first type of MOSFET chip has the switching potential;

[0023] The collector of the first type of IGBT chip is electrically connected to the first metal layer, and the collector of the first type of IGBT chip has the switching potential.

[0024] Furthermore, in the power converter described above, the second type of power device includes a second type of MOSFET chip or a second type of IGBT chip;

[0025] The drain of the second type of MOSFET chip is electrically connected to the first metal layer, and the drain of the second type of MOSFET chip does not have the switching potential;

[0026] The collector of the second type of IGBT chip is electrically connected to the first metal layer, and the collector of the second type of IGBT chip does not have the switching potential.

[0027] The present invention also provides a power conversion system, including the power converter as described in any of the preceding claims.

[0028] Compared with the prior art, one or more embodiments of the above solutions may have the following advantages or beneficial effects:

[0029] The power converter and power conversion system of the present invention, by electrically connecting the second metal layer corresponding to each of the first type of power devices to the first metal layer corresponding to at least one target second type of power device through at least one of the target vias, achieves the following: when the first type of power device M1 switches on, the common-mode current generated by the parasitic capacitance is directly guided to the electrode corresponding to the non-jumping potential of the second type of power device M2, and finally connected to the positive terminal of the first supporting capacitor through the electrode corresponding to the non-jumping potential of the second type of power device M2, thus converting it into differential-mode current, thereby suppressing the common-mode current in the power converter. Using the technical solution of the present invention, installation efficiency can be improved, and the heat dissipation uniformity of the heat sink substrate for each power device can be guaranteed.

[0030] Other features and advantages of the invention will be set forth in the description which follows, and will become apparent in part from the adjustments made thereto, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0031] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0032] Figure 1 This is a schematic diagram of the structure of a power converter based on related technologies;

[0033] Figure 2 This is a schematic diagram of the structure of an embodiment of the power converter of the present invention;

[0034] Figure 3 for Figure 2 A circuit structure topology diagram;

[0035] Figure 4 This is a schematic diagram of a three-level bridge arm power converter.

[0036] Figure 5 for Figure 4 A circuit structure topology diagram. Detailed Implementation

[0037] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that, as long as there is no conflict, the various embodiments and features in the various embodiments of the present invention can be combined with each other, and the resulting technical solutions are all within the protection scope of the present invention.

[0038] Example 1

[0039] Figure 2 This is a schematic diagram of the structure of an embodiment of the power converter of the present invention, as shown below. Figure 2 As shown, the power converter in this embodiment may include a heat dissipation substrate 10, a first insulating layer 11, at least one first type of power device, at least one second type of power device, and a power device mounting substrate 12. Figure 2 The technical solution of the present invention will be described using a first-type power device and a second-type power device as examples. The first-type power device includes a switching electrode with a switching potential, and the second-type power device includes a switching electrode without a switching potential.

[0040] In this invention, the term "jumping potential" generally refers to a large high-to-low level jump relative to a reference point (e.g., a voltage change rate dv / dt greater than 10V / μs). Conversely, a potential with a fixed potential or a small high-to-low level jump relative to the reference point (e.g., a voltage change rate dv / dt less than 2V / μs, which can be considered "virtually no jump") can be called a "non-jumping potential" (or "voltage rest point"). Of course, it is understood that the critical values ​​of the aforementioned voltage change rate dv / dt, such as 2V / μs and 10V / μs, can also fluctuate within a certain range, such as 10% or 5%, and these are not intended to limit the invention.

[0041] In one specific implementation, the first type of power device includes a first type of MOSFET chip or a first type of IGBT chip; the drain of the first type of MOSFET chip is electrically connected to the first metal layer, and the drain of the first type of MOSFET chip has the switching potential; the collector of the first type of IGBT chip is electrically connected to the first metal layer, and the collector of the first type of IGBT chip has the switching potential. The second type of power device includes a second type of MOSFET chip or a second type of IGBT chip; the drain of the second type of MOSFET chip is electrically connected to the first metal layer, and the drain of the second type of MOSFET chip does not have the switching potential; the collector of the second type of IGBT chip is electrically connected to the first metal layer, and the collector of the second type of IGBT chip does not have the switching potential.

[0042] In a specific implementation process Figure 2 Specifically, this is a schematic diagram of a half-bridge arm power converter. Figure 3 for Figure 2 A circuit structure topology diagram, such as Figure 3As shown, the structure of this half-bridge power converter may include: a half-bridge arm composed of a first power device M1 and a second power device M2 (e.g., a MOSFET chip), wherein the drain of the first power device M1 is the midpoint Nt of the bridge arm. Due to the switching between the first power device M1 and the second power device M2 on the bridge arm, the potential at the midpoint Nt of the bridge arm will jump. Therefore, the drain of the first power device M1 (i.e., the midpoint Nt of the bridge arm) is the jumping point, meaning the drain of the first power device M1 is the jumping electrode with a jumping potential. The first power device M1 can be a first type of power device in this embodiment. The drain of the second power device M2, since it is directly connected to the input terminal Ns (e.g., the positive terminal of a capacitor), can be considered a voltage static point. The second power device M2 can be a second type of power device in this embodiment.

[0043] In one specific implementation, the power device mounting substrate 12 includes a second insulating layer 121, a first metal layer 122 corresponding to each power device, and a second metal layer 123 corresponding to each power device; the second insulating layer 121 has at least one via C; in this embodiment, the heat dissipation substrate 10, the first insulating layer 11, the second metal layer 123, the second insulating layer 121, and the first metal layer 122 can be arranged sequentially from bottom to top. The first type of power device and the second type of power device are respectively disposed on the corresponding first metal layer 122.

[0044] In one specific implementation, the second metal layer 123 corresponding to each of the first type of power devices is electrically connected to the first metal layer 122 corresponding to at least one target second type of power device through at least one target via in the via C.

[0045] Specifically, such as Figures 2-3As shown, the source of the second power device M2 and the drain of the first power device M1 are connected via a printed circuit board (PCB). The drain of the second power device M2 and the source of the first power device M1 are connected to the positive and negative terminals of the first supporting capacitor C1 on the PCB, thus forming a half-bridge power converter. The two insulating layers between the drain of each type of power device and the heat sink 10 form a series parasitic capacitance. The midpoint of the parasitic capacitance corresponding to the first power device M1 is connected to the copper layer contacting the drain of the second power device M2 via a via C. When the first power device M1 switches, the common-mode current generated by the parasitic capacitance is directly guided to the drain of the second power device M2, and finally connected to the positive terminal of the first supporting capacitor C1 through the drain pin of the second power device M2, transforming into differential-mode current. The midpoint of the parasitic capacitance corresponding to the drain of the second power device M2 is no longer additionally connected, effectively reducing the capacitance of the parasitic capacitance and decreasing the impact of the parasitic inductance of the connection line from the first supporting capacitor C1 to the power device on the common-mode current.

[0046] In this embodiment, the power converter electrically connects the second metal layer 123 corresponding to each of the first type of power devices to the first metal layer 122 corresponding to at least one target second type of power device through at least one target via C. This achieves the following: when each power device corresponds to the same number or thickness of insulating media, and the first type of power device M1 switches on, the common-mode current generated by the parasitic capacitance is directly guided to the electrode corresponding to the non-jumping potential of the second type of power device M2, and finally connected to the positive terminal of the first supporting capacitor C1 through the electrode corresponding to the non-jumping potential of the second type of power device M2, thus converting it into differential-mode current, thereby suppressing the common-mode current in the power converter. Using the technical solution of this invention, installation efficiency can be improved, and the heat dissipation uniformity of the heat sink substrate 10 for each power device can be guaranteed.

[0047] In one specific implementation, the target second-type power device is the second-type power device that is closest to the first-type power device among at least one second-type power device; the target via C is the via C between the target second-type power device and the first-type power device. That is, based on the layout of each power device, the second-type power device that is closest to the first-type power device is selected as the target second-type power device, and the via C between the target second-type power device and the first-type power device is designated as the target via C. Then, the second metal layer corresponding to the first-type power device is connected to the target second-type power device through the target via C to ensure the shortest possible connection, reduce the parasitic inductance generated by the connection, prevent excessive parasitic inductance, and ensure that the current of the parasitic capacitance no longer flows to the drain of the second-type power device M2 through the connection.

[0048] In one specific implementation, the power device mounting substrate 12 may include a direct-bonding copper (DBC) substrate. Alternatively, the material of the second insulating layer 121 may include ceramic, AlN, or SiN. A first metal layer 122 and a second metal layer 123 are deposited on the second insulating layer 121, wherein the material of the first metal layer 122 and / or the material of the second metal layer 123 includes copper.

[0049] In one specific implementation, the material of the first insulating layer 11 may also include ceramic, AlN, or SiN. The thickness of the first insulating layer 11 is greater than the thickness of the second insulating layer 121.

[0050] Example 2

[0051] Figure 4 This is a schematic diagram of a three-level bridge arm power converter. Figure 5 for Figure 4 A circuit structure topology diagram, such as Figures 4-5 As shown, the three-level bridge arm power converter structure of this embodiment may include a second supporting capacitor C2, a third supporting capacitor C3, a third power device M3, a fourth power device M4, a fifth power device M5, a sixth power device M6, a seventh power device M7, and an eighth power device M8.

[0052] The drain of the third power device M3 is electrically connected to the positive terminal of the second supporting capacitor C2. The source of the third power device M3 is electrically connected to the drain of the fourth power device M4 and the drain of the seventh power device M7. The source of the fourth power device M4 is electrically connected to the drain of the fifth power device M5. The source of the fifth power device M5 is electrically connected to the drain of the sixth power device M6 and the source of the eighth power device M8. The source of the sixth power device M6 is electrically connected to the negative terminal of the third supporting capacitor C3. The drain of the eighth power device M8, the source of the seventh power device M7, and the positive terminal of the third supporting capacitor C3 are all electrically connected to the negative terminal of the second supporting capacitor C2.

[0053] Depend on Figures 4-5 It can be seen that the drains of the fourth power device M4, the fifth power device M5, the sixth power device M6, and the seventh power device M7 are all switching electrodes. Therefore, the second metal layer 123 corresponding to the drains of the fourth power device M4 and the seventh power device M7 can be connected to the first metal layer 122 corresponding to the drain of the third power device M3 through via C. The second copper layer corresponding to the drains of the fifth power device M5 and the sixth power device M6 can be connected to the first metal layer 122 corresponding to the drain of the eighth power device M8 through via C.

[0054] It should be noted that, Figure 4 The connection shown is only an example. In practical applications, the two types of power devices with the shortest distance can be selected for connection based on the specific placement of each power device.

[0055] Additionally, it should be noted that, Figure 2 and Figure 5 These are just two types of power converters of the present invention. In practical applications, other types of power converters can also be used, which will not be listed here.

[0056] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0057] It should be noted that in the description of this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means at least two.

[0058] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0059] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A power converter, characterized in that, It includes a heat dissipation substrate, a first insulating layer, at least one first type of power device, at least one second type of power device, and a power device mounting substrate; wherein, the first type of power device is a power device including a switching electrode with a switching potential, and the second type of power device is a power device including a switching electrode without a switching potential. The power device mounting substrate includes a second insulating layer, a first metal layer corresponding to each power device, and a second metal layer corresponding to each power device; the second insulating layer has at least one via. The heat dissipation substrate, the first insulating layer, the second metal layer, the second insulating layer, and the first metal layer are arranged in the following order from bottom to top; The first type of power device and the second type of power device are respectively disposed on the corresponding first metal layer; The second metal layer corresponding to each of the first type of power devices is electrically connected to the first metal layer corresponding to at least one target second type of power device through at least one of the vias.

2. The power converter according to claim 1, characterized in that, The target second type of power device is at least one second type of power device that is closest to the first type of power device; The target via is the via between the target second type of power device and the first type of power device.

3. The power converter according to claim 1, characterized in that, The power device mounting substrate includes a direct copper-clad (DBC) substrate.

4. The power converter according to claim 1, characterized in that, The material of the first insulating layer includes ceramic, AlN, or SiN.

5. The power converter according to claim 1, characterized in that, The material of the second insulating layer includes ceramic, AlN, or SiN.

6. The power converter according to claim 1, characterized in that, The material of the first metal layer and / or the material of the second metal layer includes copper.

7. The power converter according to claim 1, characterized in that, The thickness of the first insulating layer is greater than the thickness of the second insulating layer.

8. The power converter according to claim 1, characterized in that, The first type of power device includes a first type of MOSFET chip or a first type of IGBT chip; The drain of the first type of MOSFET chip is electrically connected to the first metal layer, and the drain of the first type of MOSFET chip has the switching potential; The collector of the first type of IGBT chip is electrically connected to the first metal layer, and the collector of the first type of IGBT chip has the switching potential.

9. The power converter according to claim 1, characterized in that, The second type of power devices includes second type MOSFET chips or second type IGBT chips; The drain of the second type of MOSFET chip is electrically connected to the first metal layer, and the drain of the second type of MOSFET chip does not have the switching potential; The collector of the second type of IGBT chip is electrically connected to the first metal layer, and the collector of the second type of IGBT chip does not have the switching potential.

10. A power conversion system, characterized in that, Includes the power converter as described in any one of claims 1-9.

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