Power module

Abstract

The invention discloses a power module, and relates to the technical field of power modules, the power module comprises a power loop, the power loop comprises a plurality of conductive segments which are sequentially connected end to end, a first conductive segment and a third conductive segment are opposite and spaced along a first direction, and a second conductive segment and a fourth conductive segment are opposite and spaced along a second direction, the first conductive section and the third conductive section are both connected between the second conductive section and the fourth conductive section, the current flow direction of the first conductive section is opposite to the current flow direction of the third conductive section, and the current flow direction of the second conductive section is opposite to the current flow direction of the fourth conductive section. According to the power module, the parasitic inductance of the power module can be reduced, the influence on the switching speed of the power module in the switching process can be reduced, the switching loss can be reduced, the service life of the power module can be prolonged, the probability of triggering switching oscillation can be reduced, and the service life of the power module can be prolonged. The probability that the power module affects surrounding electronic components is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power modules, in particular to a power module. BACKGROUND

[0002] In the related art, a power module can be used as a high-power electronic switch. The existing power module has a large parasitic inductance inside. In the case of high-frequency switching, the inductance in the power module reduces the switching speed and increases the switching loss. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a power module that is beneficial to reduce the parasitic inductance of the power module, reduce the impact on the switching speed of the power module during switching, reduce switching loss, prolong the service life of the power module, and also reduce the probability of triggering switching oscillation, and reduce the probability of the power module affecting surrounding electronic components.

[0004] According to the power module of the present application, the power circuit includes a plurality of conductive segments connected in sequence from head to tail, the plurality of conductive segments include a first conductive segment, a second conductive segment, a third conductive segment and a fourth conductive segment, the first conductive segment and the third conductive segment are opposite and spaced apart along a first direction, the second conductive segment and the fourth conductive segment are opposite and spaced apart along a second direction, the first conductive segment and the third conductive segment are both connected between the second conductive segment and the fourth conductive segment, wherein the current flow direction of the first conductive segment and the current flow direction of the third conductive segment are opposite, the current flow direction of the second conductive segment and the current flow direction of the fourth conductive segment are opposite, and the first direction and the second direction are perpendicular.

[0005] According to the power module of the present application, the current flow direction of the first conductive segment and the current flow direction of the third conductive segment are opposite, that is, the magnetic field direction generated by the first conductive segment and the third conductive segment can be opposite, the magnetic fields of the first conductive segment and the third conductive segment weaken each other, the current flow direction of the second conductive segment and the current flow direction of the fourth conductive segment are opposite, that is, the magnetic field direction generated by the second conductive segment and the fourth conductive segment are opposite, the magnetic fields of the second conductive segment and the fourth conductive segment weaken each other, which is beneficial to reduce the parasitic inductance of the power circuit, reduce the parasitic inductance of the power module, reduce the impact on the switching speed of the power module during switching, reduce switching loss, prolong the service life of the power module, and also reduce the probability of triggering switching oscillation, and reduce the probability of the power module affecting surrounding electronic components.

[0006] According to some embodiments of the present application, the first conductive segment and the third conductive segment each include a bridge structure.

[0007] According to some embodiments of the present application, the fourth conductive segment comprises: a positive terminal having a first terminal segment, and a negative terminal having a second terminal segment, the first terminal segment and the second terminal segment are parallel and opposite, and the current flow direction of the first terminal segment is opposite to that of the second terminal segment.

[0008] According to some embodiments of the present application, the power module further comprises: a backing plate, and a plurality of the power circuits are arranged on the same side of the backing plate, and the plurality of the power circuits are arranged in parallel through the backing plate.

[0009] According to some embodiments of the present application, the plurality of the power circuits form two groups of circuit groups, and the two groups of circuit groups are arranged in intervals along the second direction, the backing plate has a median line extending along the first direction, and the two groups of circuit groups are symmetrical about the median line.

[0010] According to some embodiments of the present application, each of the circuit groups comprises two of the power circuits, and the two of the power circuits of each of the circuit groups are arranged in intervals along the first direction, and the power circuits of the two groups of circuit groups correspond to each other along the second direction.

[0011] According to some embodiments of the present application, the plurality of the power circuits form two groups of circuit groups, each of the circuit groups comprises two of the power circuits, the two of the power circuits comprise a first power circuit and a second power circuit, the third conductive segment of the first power circuit and the first conductive segment of the second power circuit are opposite along the first direction, and the current flow direction of the third conductive segment of the first power circuit is opposite to that of the first conductive segment of the second power circuit.

[0012] According to some embodiments of the present application, the power module further comprises: an insulating layer and a first conductive layer, the backing plate has a second conductive layer, the plurality of the power circuits are arranged in parallel through the second conductive layer, the insulating layer is stacked between the first conductive layer and the second conductive layer, the first conductive layer is formed with a gate signal line, and the gate signal line is connected with the plurality of the power circuits.

[0013] According to some embodiments of the present application, the insulating layer is a ceramic layer.

[0014] According to some embodiments of the present application, the power circuit comprises a plurality of chips, and the plurality of the chips are staggered along the first direction.

[0015] Additional aspects and advantages of the present application will be given in part in the following description, become apparent from the following description, or be understood through practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0016] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the references to the figures, in which: Figure 1 is a schematic diagram of a power module according to an embodiment of the present application; Figure 2 is a top view of a power module according to an embodiment of the present application; Figure 3 is a side view of a power module according to an embodiment of the present application; Figure 4 is a schematic diagram of a plurality of power modules connected in parallel according to an embodiment of the present application.

[0017] Reference Signs: power module 1, bridge structure 11, positive terminal 12, first terminal segment 121, negative terminal 13, second terminal segment 131, chip 14, backing plate 20, second conductive layer 21, insulating layer 30, first conductive layer 40, signal pin 50, temperature sensor 60, water-cooled plate 2. DETAILED DESCRIPTION

[0018] Embodiments of the present application are described below in detail, examples of which are shown in the accompanying drawings, in which the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the accompanying drawings are exemplary and are for the purpose of explanation only, and are not to be understood as limiting the present application.

[0019] Reference is made below to Figures 1-4 A power module 1 according to an embodiment of the present application is described.

[0020] A power module 1 according to an embodiment of the present application, as shown in Figures 1-4 may include: a power circuit, the power circuit including a plurality of conductive segments connected in series, the plurality of conductive segments including a first conductive segment, a second conductive segment, a third conductive segment, and a fourth conductive segment, the first conductive segment and the third conductive segment being opposite and spaced apart along a first direction, the second conductive segment and the fourth conductive segment being opposite and spaced apart along a second direction, the first conductive segment and the third conductive segment being connected between the second conductive segment and the fourth conductive segment, wherein a current flow direction of the first conductive segment and a current flow direction of the third conductive segment are opposite, a current flow direction of the second conductive segment and a current flow direction of the fourth conductive segment are opposite, and the first direction and the second direction are perpendicular.

[0021] It should be noted that power modules can be used as high-power electronic switches. Existing power modules have a large internal parasitic inductance. Under high-frequency switching conditions, the inductance inside the power module will reduce the switching speed, increase switching losses, and affect the service life of the power module.

[0022] Based on this, this application proposes a power module 1. The power module 1 may include a power loop. Along the current flow direction within the power loop, the power loop may include multiple conductive segments connected end-to-end. These multiple conductive segments are sequentially connected and can collectively form a complete current path. The multiple conductive segments may include a first conductive segment, a second conductive segment, a third conductive segment, and a fourth conductive segment, which are connected end-to-end. The first conductive segment and the third conductive segment may be opposite to each other and spaced apart along a first direction. When the power module 1... Figure 2 When setting the direction, the first direction is Figure 2 The Y-direction in the middle. The second conductive segment and the fourth conductive segment can be opposite to each other and spaced apart along the second direction, when power module 1 as... Figure 2 When setting the direction, the second direction is Figure 2 In the X-direction, the first direction and the second direction are perpendicular. The current flow direction of the first conductive segment and the current flow direction of the third conductive segment can be parallel to the second direction, and the current flow direction of the second conductive segment and the current flow direction of the fourth conductive segment can be parallel to the first direction.

[0023] When the power circuit is turned on, current flows within it. This current can flow along the arrangement of the first, second, third, and fourth conductive segments. The current passing through each segment generates a magnetic field. The current flow direction in the first and third conductive segments is opposite, meaning their magnetic fields can be opposite in direction and can weaken each other. Similarly, the current flow direction in the second and fourth conductive segments is also opposite, further reducing the parasitic inductance of the power circuit and power module 1. This reduces the probability of the power module 1 affecting its switching speed during switching, decreases switching losses, extends its lifespan, reduces the probability of switching oscillations, and minimizes the probability of the power module 1 affecting surrounding electronic components.

[0024] In some embodiments of the present invention, both the first conductive segment and the third conductive segment include a bridge structure 11.

[0025] The bridge structure 11 can be constructed as a copper clip. It can be used to connect to the chip 14 in the power circuit and the copper plate of the power module 1. The bridge structure 11 can be connected to the pins of the chip 14 and the copper plate through silver sintering, soldering, or other methods. This improves the connection strength between the bridge structure 11 and the chip 14 and the copper plate, thus enhancing the reliability of the power module 1. Furthermore, by setting the bridge structure 11, it can also conduct electricity. Compared to wires in existing technologies, this further reduces the parasitic inductance of the power circuit and the power module 1, further reducing the probability of factors affecting the switching speed of the power module 1 during switching, further reducing switching losses, and further extending the service life of the power module 1.

[0026] In some embodiments of the present invention, such as Figure 1 As shown, the fourth conductive segment may include a positive terminal 12 and a negative terminal 13. The positive terminal 12 has a first terminal segment 121, and the negative terminal 13 has a second terminal segment 131. The first terminal segment 121 and the second terminal segment 131 are parallel and opposite to each other, and the current flow direction of the first terminal segment 121 is opposite to the current flow direction of the second terminal segment 131.

[0027] The positive terminal 12 and the negative terminal 13 can be connected to the drive unit of the power module 1. Current can flow into the power circuit through the positive terminal 12 and flow out of the power circuit through the negative terminal 13, thus constructing a complete power circuit. The positive terminal 12 may have a first terminal segment 121, and the negative terminal 13 may have a second terminal segment 131. The first terminal segment 121 and the second terminal segment 131 may be parallel and opposite to each other, and the first terminal segment 121 and the second terminal segment 131 may be spaced apart. When current flows through the first terminal segment 121 and the second terminal segment 131, a corresponding magnetic field is generated. The current flow direction of the first terminal segment 121 can be opposite to that of the second terminal segment 131, that is, the magnetic field directions of the first terminal segment 121 and the second terminal segment 131 can be opposite. The magnetic fields of the first terminal segment 121 and the second terminal segment 131 weaken each other, which is beneficial to further reduce the parasitic inductance of the power circuit, further reduce the parasitic inductance of the power module 1, further reduce the probability of affecting the switching speed of the power module 1 during the switching process, further reduce switching losses, and further extend the service life of the power module 1.

[0028] As an example, both the first terminal segment 121 and the second terminal segment 131 can extend along a third direction, and the current flow direction of the first terminal segment 121 and the current flow direction of the second terminal segment 131 can both be parallel to the third direction. When the power module 1 is as follows... Figure 1 When setting the direction, the third direction can be... Figure 1In the Z-direction, the first direction, the second direction, and the third direction can be perpendicular to each other.

[0029] As an example, the positive terminal 12 and the negative terminal 13 can be made of copper with high conductivity. The surfaces of the positive terminal 12 and the negative terminal 13 can be tin-plated or silver-plated, which helps to reduce the oxidation risk of the positive terminal 12 and the negative terminal 13.

[0030] In some embodiments of the present invention, such as Figure 1 and Figure 3 As shown, the power module 1 may also include: a liner 20, multiple power circuits, multiple power circuits located on the same side of the liner 20, and multiple power circuits connected in parallel through the liner 20.

[0031] Multiple power circuits can be configured, and these circuits can be located on the same side of the liner 20 along its thickness. This arrangement reduces the thickness of the power module 1, lowers its assembly complexity, ensures similar connection paths between the circuits and the liner 20, and improves the consistency of the power circuits. The liner 20 can also be connected in parallel, serving as a common conductive and supporting structure. This facilitates even current distribution across the circuits, reduces circulating current losses in the power module 1, and improves its reliability. Furthermore, by connecting multiple power circuits in parallel, the total parasitic inductance of the power module 1 is no greater than that of a single power circuit, further reducing the parasitic inductance of the power module 1.

[0032] As an example, the liner 20 may include multiple layers, and the side of the liner 20 facing the power circuit may be constructed as a copper layer, through which multiple power circuits can be connected in parallel via the respective copper layers.

[0033] In some embodiments of the present invention, multiple power circuits form two sets of circuit groups, which are arranged at intervals along a second direction. The liner 20 has a midline extending along a first direction, and the two sets of circuit groups are symmetrical about the midline.

[0034] Multiple power loops can form two loop groups, each loop group can include multiple power loops, the two loop groups can be arranged at intervals along a second direction, and the two loop groups can be arranged opposite each other along the second direction. The liner 20 has a center line extending along a first direction, the center line can be located between the two loop groups, the two loop groups are symmetrical about the center line, that is, the number of power loops in the two loop groups is the same, and the relative positional relationship of the multiple power loops is the same.

[0035] By setting two sets of circuit groups symmetrical about the midline, it is beneficial to ensure that the connection path length between the chip 14 in each power circuit and the substrate 20, the corresponding positive terminal 12, and the corresponding negative terminal 13 is consistent. This is beneficial to ensure that the parameters of multiple power circuits are consistent, to further ensure that the current of multiple power circuits is evenly distributed, to improve the current sharing characteristics of multiple chips 14, and to further improve the reliability of power module 1.

[0036] In some embodiments of the present invention, each circuit group may include two power circuits, the two power circuits of each circuit group are arranged at intervals along a first direction, and the power circuits of the two circuit groups correspond one-to-one along a second direction.

[0037] Each circuit group can include two power circuits. The two power circuits in each circuit group can be arranged at intervals along the first direction, and the power circuits of the two circuit groups can correspond one-to-one along the second direction. Each power circuit in each circuit group has a power circuit corresponding to it along the second direction. This is beneficial to improve the symmetry of the two circuit groups, to further achieve the consistency of multiple power circuit parameters, to further make the current of multiple power circuits more evenly distributed, to further improve the current sharing characteristics of the multi-chip 14, and to further improve the reliability of the power module 1.

[0038] In some embodiments of the present invention, multiple power circuits form two circuit groups, each circuit group including two power circuits, the two power circuits including a first power circuit and a second power circuit, the third conductive segment of the first power circuit and the first conductive segment of the second power circuit are opposite to each other along a first direction, and the current flow direction of the third conductive segment of the first power circuit is opposite to the current flow direction of the first conductive segment of the second power circuit.

[0039] Multiple power circuits can form two circuit groups, each circuit group including two power circuits. Therefore, the power module 1 in this application can include four power circuits. The two power circuits can include a first power circuit and a second power circuit. The first and second power circuits can be arranged at intervals along a first direction, and the third conductive segment of the first power circuit and the first conductive segment of the second power circuit can be opposite each other along the first direction. When current flows through the third conductive segment of the first power circuit and the first conductive segment of the second power circuit, both can generate magnetic fields. The current flow direction of the third conductive segment of the first power circuit is opposite to that of the first conductive segment of the second power circuit, and the magnetic fields generated by the third conductive segment of the first power circuit and the first conductive segment of the second power circuit are opposite in direction. The magnetic fields of the third conductive segment of the first power circuit and the first conductive segment of the second power circuit weaken each other, which is beneficial for further reducing the parasitic inductance of the power module 1, further reducing the probability of affecting the switching speed of the power module 1 during the switching process, further reducing switching losses, and further extending the service life of the power module 1.

[0040] In some embodiments of the present invention, such as Figure 1 and Figure 2 As shown, the power module 1 may further include: an insulating layer 30 and a first conductive layer 40, a liner 20 having a second conductive layer 21, multiple power circuits being connected in parallel through the second conductive layer 21, the insulating layer 30 being stacked between the first conductive layer 40 and the second conductive layer 21, the first conductive layer 40 having a gate signal line, and the gate signal line being connected to multiple power circuits.

[0041] The substrate 20 may have a second conductive layer 21, which may be the copper layer of the substrate 20 in the above embodiment. Multiple power circuits can be connected in parallel through the second conductive layer 21. The second conductive layer 21 has the advantages of large conductive area and low resistance. The second conductive layer 21 can serve as a common parallel carrier for multiple power circuits, which helps to reduce the contact resistance and distributed impedance of the parallel nodes and further reduce the circulating current loss of the power module 1. Moreover, the second conductive layer 21 is constructed as a planar structure, making it easier to keep the connection path length and contact area of ​​multiple power circuits consistent. This helps to further achieve the consistency of parameters of multiple power circuits, further improve the current sharing characteristics of the multi-chip 14, and further improve the reliability of the power module 1.

[0042] The side of the second conductive layer 21 facing multiple power circuits may have an insulating layer 30 and a first conductive layer 40, with the insulating layer 30 stacked between the first conductive layer 40 and the second conductive layer 21. The first conductive layer 40 may have a gate signal line, which can be connected to multiple power circuits. The connection path length between the multiple power circuits and the gate signal line can be consistent, which helps to reduce the signal delay difference between the multiple power circuits and facilitates the effect of controlling the synchronous conduction or cutoff of multiple power circuits.

[0043] The insulating layer 30 has insulating properties and can isolate the first conductive layer 40 and the second conductive layer 21. This helps to isolate the gate signal line from the power circuit, further reduce the parasitic inductance of the power module 1, effectively isolate the gate signal line from the large current of the power circuit, reduce the impact of the large current of the power circuit on the gate signal line, and further improve the reliability of the power module 1.

[0044] As an example, the substrate 20 can be formed by stacking copper layers (i.e., the second conductive layer 21), ceramic layers, and copper layers. The copper layer, as a carrier for heat conduction and dissipation, has the advantages of large area and fast heat conduction, which is conducive to achieving the effect of uniformly distributing heat to the entire substrate 20 and improving the heat dissipation effect of the power module 1.

[0045] In some embodiments of the present invention, the insulating layer 30 is a ceramic layer.

[0046] Ceramic has good and stable insulation properties, which helps to enhance the isolation effect between the gate signal line and the power circuit, further reduce the parasitic inductance of power module 1, further achieve the effect of effectively isolating the gate signal line and the power circuit from the large current, further reduce the impact of the large current of the power circuit on the gate signal line, and further improve the reliability of power module 1.

[0047] In some embodiments of the present invention, such as Figure 2 As shown, the power circuit may include multiple chips 14, which are staggered along a first direction.

[0048] The power circuit may include multiple chips 14, which can be staggered along the first direction. This helps to reduce the size of the power circuit along the first direction, which helps to reduce the size of the power module 1 along the first direction, which helps to improve the structural compactness of the power module 1, which helps to reduce the space occupied by the power module 1, and which helps to reduce the difficulty of arranging the power module 1.

[0049] As an example, the power module 1 may include multiple signal pins 50, which may be evenly disposed on the second conductive layer 21. Each signal pin 50 may correspond one-to-one with a multiple chip 14, and the chip 14 may be connected to its corresponding signal pin 50 via a wire. The signal pins 50 can be used to transmit gate drive signals. An external controller can send control commands to the corresponding chip 14 through the signal pins 50, which is beneficial for controlling the start / stop and energy conversion regulation of the power module 1. The multiple signal pins 50 may be evenly disposed on the side of the second conductive layer 21 facing multiple power circuits, which is beneficial for achieving the effect of pins emerging from the underside of the power module 1, shortening the connection distance between the signal pins 50 and the corresponding chip 14, reducing stray inductance of the gate signal circuit, and further reducing parasitic inductance of the power module 1.

[0050] As an example, power module 1 may include a temperature sensor 60, which may be an NCT (Negative Temperature Coefficient). The temperature sensor 60 can be connected via a copper plate and a second conductive layer 21, and can be used to detect the temperature of the liner 20. The temperature sensor 60 can communicate with an external controller via an adjacent signal pin 50. When the temperature exceeds a safety threshold, a control loop can trigger operations such as power-off, which helps to further improve the reliability of power module 1.

[0051] As an example, multiple power modules 1 can be mounted on the same water-cooled plate 2. The multiple power modules 1 can be connected in parallel, and the cooling medium in the water-cooled plate 2 can cool the multiple power modules 1 simultaneously, which is beneficial to improving the heat dissipation effect of the multiple power modules 1.

[0052] Other configurations and operations of the power module 1 according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "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.

[0054] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A power module, characterized by The power module (1) comprises: a power circuit, the power circuit comprising a plurality of conductive sections connected in sequence, the plurality of conductive sections comprising a first conductive section, a second conductive section, a third conductive section and a fourth conductive section, the first conductive section and the third conductive section being opposite and spaced apart along a first direction, the second conductive section and the fourth conductive section being opposite and spaced apart along a second direction, the first conductive section and the third conductive section being connected between the second conductive section and the fourth conductive section, wherein a current flow direction of the first conductive section is opposite to a current flow direction of the third conductive section, and a current flow direction of the second conductive section is opposite to a current flow direction of the fourth conductive section, the first direction being perpendicular to the second direction.

2. The power module of claim 1, wherein, The first conductive section and the third conductive section each comprise a bridge structure (11).

3. The power module of claim 1, wherein, The fourth conductive section comprises a positive terminal (12) and a negative terminal (13), the positive terminal (12) having a first terminal section (121), the negative terminal (13) having a second terminal section (131), the first terminal section (121) and the second terminal section (131) being parallel and opposite, the current flow direction of the first terminal section (121) being opposite to the current flow direction of the second terminal section (131).

4. The power module of claim 1, wherein, The power module (1) further comprises a backing plate (20), the power circuit being a plurality of power circuits, the plurality of power circuits being arranged on the same side of the backing plate (20), the plurality of power circuits being arranged in parallel through the backing plate (20).

5. The power module of claim 4, wherein, The plurality of power circuits form two groups of circuits, the two groups of circuits being arranged in parallel along the second direction, the backing plate (20) having a center line extending along the first direction, the two groups of circuits being symmetrical about the center line.

6. The power module of claim 5, wherein, Each group of circuits comprises two power circuits, the two power circuits of each group of circuits being arranged in parallel along the first direction, and the power circuits of the two groups of circuits corresponding to each other along the second direction.

7. The power module of claim 4, wherein, The plurality of power circuits form two groups of circuits, each group of circuits comprising two power circuits, the two power circuits comprising a first power circuit and a second power circuit, the third conductive section of the first power circuit and the first conductive section of the second power circuit being opposite along the first direction, the current flow direction of the third conductive section of the first power circuit being opposite to the current flow direction of the first conductive section of the second power circuit.

8. The power module of claim 4, wherein, The power module (1) further comprises an insulating layer (30) and a first conductive layer (40), the backing plate (20) having a second conductive layer (21), the plurality of power circuits being arranged in parallel through the second conductive layer (21), the insulating layer (30) being laminated between the first conductive layer (40) and the second conductive layer (21), the first conductive layer (40) being formed with a gate signal line, the gate signal line being connected with the plurality of power circuits.

9. The power module of claim 8, wherein, The insulating layer (30) is a ceramic layer.

10. The power module of any one of claims 1-9, wherein, The power circuit comprises a plurality of chips (14), the plurality of chips (14) being staggered along the first direction.

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