High-reliability power module

Abstract

The utility model relates to a high-reliability power module, which comprises a heat dissipation bottom plate and a shell connected to the heat dissipation bottom plate, the power terminal is connected to the copper-clad ceramic through an ultrasonic welding process, and then the copper-clad ceramic is welded on the heat dissipation bottom plate; the signal terminal and the power terminal are injection-molded in the shell together, and the bonding surface of the signal terminal is connected with the copper-clad ceramic through aluminum wire bonding; and a high-temperature sealant is also coated at the joint between the heat dissipation bottom plate and the shell. The power module is compact and reasonable in structure and convenient to operate, and the reliability and the service life of the power module are remarkably improved and prolonged by adopting the measures of fastening the heat dissipation bottom plate and the shell through the self-tapping screws, innovating the bonding process, optimizing the structural design and the like. The improvement measures not only solve the problems of the existing power module in the aspects of heat dissipation performance, bonding process stability, mechanical vibration resistance and the like, but also meet the requirements of the electric vehicle market on the high-reliability power module.

Description

Technical Field

[0001] This utility model relates to the field of power module technology, and in particular to a high-reliability power module. Background Technology

[0002] With the booming development of the electric vehicle market and continuous technological advancements, the performance and reliability of power modules, as core components of electric vehicle motor drive systems, have become key factors restricting the overall performance of electric vehicles. Power modules must maintain high stability and reliability under long-term, high-load operating conditions to ensure the safe operation and high efficiency of electric vehicles. However, existing power modules face several technical challenges in their design and manufacturing processes that urgently need to be addressed.

[0003] The heat dissipation performance of a power module is one of the important factors affecting its reliability. The bonding strength and heat dissipation efficiency between the heat sink and the housing directly affect the thermal management effect of the power module. In the existing technology, the connection method between the heat sink and the housing may have problems such as insufficient bonding strength and low heat dissipation efficiency, which makes the power module prone to failure in high-temperature environments, affecting the performance and safety of electric vehicles.

[0004] The stability of the bonding process for power modules is also a key factor affecting their reliability. The bonding quality between power and signal terminals and the copper-clad ceramic directly affects the electrical performance and lifespan of the power module. In existing technologies, due to the instability of the bonding process, problems such as broken bonding wires and poor soldering are prone to occur, leading to a decrease in the performance of the power module and even causing failure.

[0005] To address the aforementioned technical problems, designing a highly reliable power module and process is of paramount importance. The new solution needs to resolve issues with existing power modules in terms of heat dissipation, bonding process stability, and resistance to mechanical vibration, in order to improve the overall performance and reliability of the power module and meet the demands of the electric vehicle market for high-performance, high-reliability power modules. Therefore, this application aims to propose an innovative structural and process solution to overcome the shortcomings of existing technologies and improve the reliability and lifespan of the power module.

[0006] Therefore, we propose a highly reliable power module. Utility Model Content

[0007] To address the shortcomings of existing manufacturing technologies, the applicant provides a highly reliable power module. By employing self-tapping screws to secure the heat dissipation base plate to the casing, innovating the bonding process, and optimizing the structural design, the reliability and service life of the power module are significantly improved.

[0008] The technical solution adopted in this utility model is as follows:

[0009] A high-reliability power module includes a heat sink base plate and components connected to the heat sink base plate:

[0010] The outer casing is fastened to the heat sink base plate with self-tapping screws to enhance the bonding strength and resistance to mechanical vibration;

[0011] The power terminals are connected to the copper-clad ceramic using an ultrasonic welding process, and the copper-clad ceramic is then welded to the heat sink base plate to improve the welding effect and stability.

[0012] The signal terminals are injection molded together with the power terminals in the housing, and the bonding surfaces of the signal terminals are connected to the copper-clad ceramic via aluminum wire bonding.

[0013] The connection between the heat dissipation base plate and the outer shell is also coated with high-temperature sealant to further improve the bonding strength and high-temperature resistance.

[0014] In one embodiment, the pin soldering surface of the power terminal is textured to enhance the welding effect of ultrasonic welding.

[0015] In one embodiment, during the injection molding process of the signal terminal into the housing, the bonding surface of the signal terminal is made flush with the plastic surface to improve the housing's ability to enclose the signal terminal.

[0016] In one embodiment, a circular boss structure is added to the back of the signal terminal bonding surface of the housing to provide support for the gap between the heat sink base plate and the housing and to prevent vibration during the bonding process.

[0017] In one embodiment, the plastic thickness below the bonding surface of the signal terminal is at least 2 mm to provide good cushioning and improve the problem of bonding failure during the bonding process.

[0018] In one embodiment, the heat dissipation base plate and the outer shell have pre-drilled holes of a certain size for installing self-tapping screws, which are then tightened under a certain torque requirement to further enhance the bonding force.

[0019] In one embodiment, the power terminal and the housing are pre-molded as a single piece to improve the bonding strength between the heat sink base plate and the housing.

[0020] In one embodiment, the high-temperature sealant is used to fill the tiny gaps between the heat dissipation base plate and the housing to improve the module's sealing performance and high-temperature resistance.

[0021] In one embodiment, the power module further includes bonding aluminum wires for bonding the signal terminal bonding surfaces to the copper-clad ceramic to ensure stable transmission of electrical signals.

[0022] It also includes a top cover, which is connected to the outer shell by a snap-fit ​​to form a complete modular package.

[0023] The beneficial effects of this utility model are as follows:

[0024] This utility model features a compact and rational structure, and is easy to operate. By employing self-tapping screws to secure the heat dissipation base plate to the outer shell, an innovative bonding process, and optimized structural design, it significantly improves the reliability and service life of the power module. These improvements not only solve the problems of existing power modules in terms of heat dissipation performance, bonding process stability, and resistance to mechanical vibration, but also meet the demands of the electric vehicle market for high-performance, high-reliability power modules. In particular, by optimizing the connection method and bonding process between the heat dissipation base plate and the outer shell, and by comprehensively considering the balance between mechanical strength, thermal management, and electrical performance, the power module of this utility model maintains stable performance under various harsh environments, providing a strong guarantee for the safe operation and high efficiency of electric vehicles.

[0025] In addition, this utility model also has the following advantages:

[0026] This invention significantly improves the bonding strength between the heat sink base plate and the outer shell by using self-tapping screws to secure them together. Compared to traditional connection methods, the use of self-tapping screws not only simplifies the installation process but also greatly enhances the overall mechanical strength of the module. In high-temperature and high-vibration environments, this fastening method effectively reduces the risk of loosening due to vibration, thereby ensuring the stability and reliability of the power module. Furthermore, applying a layer of high-temperature sealant to the base plate further enhances the sealing and high-temperature resistance between the heat sink base plate and the outer shell, providing more reliable protection for the power module. This design not only improves the module's heat dissipation efficiency but also extends its service life, meeting the electric vehicle market's demand for high-performance, high-reliability power modules.

[0027] This invention innovates the bonding process for power and signal terminals by employing ultrasonic welding and aluminum wire bonding technology. The application of ultrasonic welding ensures a stronger connection between the power terminals and the copper-clad ceramic, reducing the possibility of welding defects and improving bonding quality. Simultaneously, aluminum wire bonding technology ensures the quality of the electrical connection between the signal terminal bonding surface and the copper-clad ceramic, reducing signal transmission loss and interference. This innovative bonding process not only improves the electrical performance of the power module but also enhances its resistance to mechanical vibration, ensuring stable operation in various harsh environments. Furthermore, by optimizing the structure on the back of the housing and around the signal terminal bonding surface, such as increasing the circular boss and the thickness of the plastic layer below the signal terminal bonding surface, problems such as broken bonding wires and incomplete soldering are further prevented, improving production efficiency.

[0028] This invention fully considers the balance between mechanical strength, thermal management, and electrical performance in the structural design of the power module. By optimizing the coordinated operation of key components such as the heat dissipation base plate, outer shell, top cover, power terminals, signal terminals, and copper-clad ceramic, the module maintains stable performance even in harsh environments such as high temperature, high humidity, and high vibration. In particular, the design of the heat dissipation base plate not only rapidly dissipates heat generated inside the module, preventing performance degradation due to overheating, but also enhances the module's heat dissipation efficiency and sealing performance through its tight connection with the outer shell and the sealing effect of high-temperature sealant. Simultaneously, the design of the outer shell and top cover not only provides mechanical protection but also enhances the module's vibration resistance through optimized design. This comprehensive structural design not only improves the reliability and service life of the power module but also provides strong support for the continued development of the electric vehicle market. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of this utility model.

[0030] Figure 2 This is a structural schematic diagram of the present invention (after removing the top cover and outer shell).

[0031] Figure 3 This is a cross-sectional structural diagram of the present invention.

[0032] Figure 4 for Figure 1 A magnified view of part I in the middle.

[0033] Figure 5 This is a schematic diagram of the structure of this utility model (after removing the top cover).

[0034] Figure 6 for Figure 1 A magnified view of part II in the middle section.

[0035] Figure 7 This is a cross-sectional view of the outer shell of this utility model.

[0036] in:

[0037] 10. Heat sink base plate; 11. Housing; 12. Top cover; 13. Power terminal; 14. Signal terminal; 15. Self-tapping screw; 16. Copper-clad ceramic; 17. Bonded aluminum wire; 1101. Circular boss; 1102. Plastic surface of housing; 1401. Bonding surface of signal terminal. Detailed Implementation

[0038] The specific embodiments of this utility model are described below with reference to the accompanying drawings.

[0039] like Figures 1-7As shown, this embodiment discloses a high-reliability power module, which, compared with existing power modules, further optimizes the structure by adding self-tapping screws 15 between the heat sink base plate 10 and the housing 11, and optimizing the bottom plastic part structure of the signal terminal bonding surface 1401. In terms of manufacturing process, ultrasonic welding, which provides better welding results, is adopted, and the sealant is replaced with high-temperature sealant. These improvements enhance the stability of the bonding process, strengthen the fastening force between the heat sink base plate 10 and the housing 11, and improve the module's resistance to mechanical vibration, thereby increasing the reliability of the power module. These improvements not only enhance the module's mechanical strength but also significantly improve its stability under high-temperature and high-vibration environments. The use of self-tapping screws 15 makes the connection between the heat sink base plate 10 and the housing 11 more secure, reducing the risk of loosening due to vibration. The application of ultrasonic welding ensures the welding quality between the power terminal 13 and the copper-clad ceramic 16, reducing the possibility of welding defects. The use of high-temperature sealant further enhances the module's sealing performance, preventing external environmental corrosion of the internal circuitry and thus extending the module's service life.

[0040] Specifically, the module in this embodiment includes key components such as power terminals 13, a heat sink 10, a housing 11, a top cover 12, signal terminals 14, copper-clad ceramic 16, and self-tapping screws 15. The coordinated operation of these components enables the module to maintain stable performance even in harsh environments such as high temperature, high humidity, and high vibration. As a key component for current transmission, the connection quality between the power terminals 13 and the copper-clad ceramic 16 directly affects the module's electrical performance. The heat sink 10 is responsible for rapidly dissipating heat generated inside the module, preventing performance degradation due to overheating. The housing 11 and top cover 12 not only provide mechanical protection but also enhance the module's sealing and vibration resistance through optimized design. The design of the signal terminals 14 ensures the stability of signal transmission and reduces the possibility of signal interference and loss.

[0041] Specifically, in this embodiment, the power terminal 13 is ultrasonically welded to the copper-clad ceramic 16, which is then welded to the heat sink base plate 10. The heat sink base plate 10 and the outer casing 11 are tightened together with self-tapping screws 15 and sealed with high-temperature sealant to enhance the bonding strength and high-temperature resistance. The application of ultrasonic welding technology makes the connection between the power terminal 13 and the copper-clad ceramic 16 more secure, reducing the possibility of welding defects. The welding of the copper-clad ceramic 16 to the heat sink base plate 10 ensures rapid heat conduction and prevents local overheating. The use of self-tapping screws 15 makes the connection between the heat sink base plate 10 and the outer casing 11 more secure, reducing the risk of loosening due to vibration. The use of high-temperature sealant further enhances the sealing performance of the module, preventing external environmental corrosion of the internal circuitry and thus extending the module's service life.

[0042] The power terminal 13 and signal terminal 14 are pre-injected into the housing 11 to form a single unit. During the injection molding process, the bonding surface 1401 of the signal terminal is flush with the plastic surface 1102, which improves the housing 11's encapsulation of the signal terminal 14. This integrated injection molding design not only simplifies the manufacturing process but also enhances the module's structural strength. The flush design of the bonding surface 1401 and the plastic surface 1102 ensures the stability of the signal terminal 14 within the housing 11, reducing signal loss or interference caused by vibration. Furthermore, this design improves the module's sealing, preventing external environmental corrosion of the internal circuitry.

[0043] Each signal terminal bonding surface 1401 is bonded to the copper-clad ceramic 16 via aluminum wire bonding (i.e., bonding aluminum wire 17), and the top cover 12 is snapped onto the housing 11. In this way, the power terminal 13, heat sink 10, housing 11, top cover 12, signal terminal 14, copper-clad ceramic 16, self-tapping screws 15, and bonding aluminum wire 17 are assembled into a complete module. The application of aluminum wire bonding technology ensures the quality of the electrical connection between the signal terminal bonding surface 1401 and the copper-clad ceramic 16, reducing signal transmission loss and interference. The snap-fit ​​connection design of the top cover 12 to the housing 11 not only simplifies the assembly process but also improves the module's sealing and vibration resistance. The overall module's structural design fully considers the balance between mechanical strength, thermal management, and electrical performance, ensuring stable operation of the module in various harsh environments.

[0044] To enhance the bonding strength between the heat dissipation base plate 10 and the outer casing 11, a layer of high-temperature sealant is applied to the base plate. Simultaneously, pre-drilled holes of specific dimensions are made on both the heat dissipation base plate 10 and the outer casing 11. Self-tapping screws 15 are then used to tighten the heat dissipation base plate 10 and the outer casing 11 together under specific torque requirements, further improving the bonding force. The use of high-temperature sealant not only strengthens the bonding strength between the heat dissipation base plate 10 and the outer casing 11 but also improves the module's high-temperature resistance. The use of self-tapping screws 15 ensures a more secure connection between the heat dissipation base plate 10 and the outer casing 11, reducing the risk of loosening due to vibration. This design not only improves the module's mechanical strength but also enhances its stability under high-temperature and high-vibration environments.

[0045] A further improvement is that the power terminal 13 is ultrasonically welded to the copper-clad ceramic 16, and the welding surface of the power terminal leads is textured to enhance the welding effect of the ultrasonic welding. The power terminal 13 and the housing 11 are integrally injection molded, thereby improving the bonding strength between the heat dissipation base plate 10 and the housing 11. The application of ultrasonic welding technology makes the connection between the power terminal 13 and the copper-clad ceramic 16 more robust, reducing the possibility of welding defects. The textured treatment of the welding surface of the power terminal leads further increases the welding area and improves the welding quality. The integral injection molding design of the power terminal 13 and the housing 11 not only simplifies the manufacturing process but also improves the structural strength and sealing of the module. These improvements significantly improve the reliability and service life of the module.

[0046] To improve the stability of the bonding aluminum wires to the signal terminals, the plastic surface 1102 of the housing is designed to be flush with the signal terminal 14. This improves the enclosure of the signal terminal 14 by the housing 11 and enhances the stability of the bonding process. The flush design of the plastic surface 1102 with the signal terminal 14 ensures the stability of the signal terminal 14 within the housing 11, reducing signal loss or interference caused by vibration. This design also improves the module's sealing, preventing external environmental corrosion of the internal circuitry. Furthermore, this design simplifies the manufacturing process and improves production efficiency.

[0047] In another embodiment, a circular boss 1101 is added to the back of the bonding surface 1401 of the housing signal terminals to provide support for the gap between the heat sink base plate 10 and the housing 11, which is bent due to process requirements. This prevents vibration during bonding and avoids affecting the bonding effect. The design of the circular boss 1101 not only provides support for the gap between the heat sink base plate 10 and the housing 11, but also reduces vibration during bonding and improves bonding quality. This design significantly improves the mechanical strength and vibration resistance of the module, ensuring stable operation of the module in various harsh environments.

[0048] In another embodiment, the thickness of the plastic below the signal terminal bonding surface 1401 is increased. Actual verification shows that the plastic thickness of the outer shell plastic surface 1102 needs to be at least 2mm. This provides a good buffering effect during bonding, significantly improving the problem of bonding pad loss. Increasing the plastic thickness below the signal terminal bonding surface 1401 not only improves the buffering effect during bonding but also reduces bonding pad loss. This design significantly improves the bonding quality and production efficiency of the module, ensuring stable operation of the module in various harsh environments.

[0049] In summary, the new solution uses self-tapping screws 15 to secure the heat sink base plate 10 to the housing 11, along with ultrasonic welding of the power terminals 13 and high-temperature sealant. This enhances the bonding strength and resistance to mechanical vibration between the housing 11 and the base plate 10, thereby improving the reliability of the power module. Simultaneously, the new solution optimizes the structure around the back of the housing 11 and the signal terminal bonding surface 1401 to prevent bonding wire breakage and cold solder joints, improving production efficiency and power module reliability. These improvements not only enhance the module's mechanical strength but also significantly improve its stability under high temperature and high vibration environments. The use of self-tapping screws 15 makes the connection between the heat sink base plate 10 and the housing 11 more secure, reducing the risk of loosening due to vibration. The application of ultrasonic welding ensures the welding quality between the power terminals 13 and the copper-clad ceramic 16, reducing the possibility of welding defects. The use of high-temperature sealant further enhances the module's sealing performance, preventing external environmental corrosion of the internal circuitry and extending the module's lifespan. The optimized structural design of the back of the housing 11 and the surrounding structure of the signal terminal bonding surface 1401 significantly improves bonding quality and production efficiency, ensuring stable operation of the module in various harsh environments.

[0050] The above description is an explanation of the present utility model and not a limitation thereof. The scope of the present utility model is defined by the claims. Within the protection scope of the present utility model, any form of modification may be made.

Claims

1. A high-reliability power module, characterized in that, Includes a heat sink base plate (10) and components connected to the heat sink base plate (10): The outer casing (11) is fastened to the heat dissipation base plate (10) by self-tapping screws (15) to enhance the bonding strength and resistance to mechanical vibration; The power terminal (13) is connected to the copper-clad ceramic (16) by ultrasonic welding process, and the copper-clad ceramic (16) is then welded to the heat dissipation base plate (10) to improve the welding effect and stability. The signal terminal (14) is injection molded together with the power terminal (13) in the housing (11), and the bonding surface (1401) of the signal terminal is connected to the copper-clad ceramic (16) by aluminum wire bonding; The connection between the heat dissipation base plate (10) and the outer shell (11) is also coated with high-temperature sealant to further improve the bonding strength and high-temperature resistance.

2. The high-reliability power module according to claim 1, characterized in that, The pin welding surface of the power terminal (13) is treated with a textured surface to enhance the welding effect of ultrasonic welding.

3. A high-reliability power module according to claim 1, characterized in that, During the injection molding process of the signal terminal (14) into the housing (11), the bonding surface (1401) of the signal terminal is made flush with the plastic surface (1102) to improve the encapsulation of the signal terminal (14) by the housing (11).

4. A high-reliability power module according to claim 1, characterized in that, A circular boss (1101) structure is added to the back of the signal terminal bonding surface (1401) of the housing (11) to provide support for the gap between the heat dissipation base plate (10) and the housing (11) and to prevent vibration during the bonding process.

5. A high-reliability power module according to claim 1, characterized in that, The plastic thickness below the bonding surface (1401) of the signal terminal is at least 2 mm to provide good cushioning and improve the problem of point drop during the bonding process.

6. A high-reliability power module according to claim 1, characterized in that, The heat dissipation base plate (10) and the outer shell (11) have pre-drilled holes of a certain size for installing self-tapping screws (15) and tightening them under a certain torque requirement to further enhance the bonding force.

7. A high-reliability power module according to claim 1, characterized in that, The power terminal (13) and the outer shell (11) are integrally injection molded in the early stage to improve the bonding force between the heat dissipation base plate (10) and the outer shell (11).

8. A high-reliability power module according to claim 1, characterized in that, The high-temperature sealant is used to fill the tiny gaps between the heat dissipation base plate (10) and the outer shell (11) to improve the module's sealing performance and high-temperature resistance.

9. A high-reliability power module according to claim 1, characterized in that, The power module also includes bonding aluminum wires (17) for bonding the signal terminal bonding surface (1401) to the copper-clad ceramic (16) to ensure stable transmission of electrical signals.

10. The power module according to any one of claims 1 to 9, characterized in that, It also includes a top cover (12), which is connected to the outer shell (11) by a snap fastener to form a complete modular package.

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