High-temperature-resistant shell structure for SiC power device

Abstract

The utility model discloses a high-temperature-resistant shell structure for a SiC power device, which comprises a plastic frame, and three AC power terminals are fixed at the bottom of the plastic frame through integral injection molding. According to the utility model, the plastic frame, the DC1 power terminal, the DC2 power terminal and the AC power terminal are subjected to integrated injection molding, so that the phenomena of independent assembly and terminal plugging hole position reservation are avoided, and a better integrated stable effect is achieved; the insulating layer prefabricated member made of PPA, PPS or insulating ceramic materials is clamped, positioned, separated and insulated between the DC1 power terminal and the DC2 power terminal in advance, the high temperature resistance and the insulating property are both superior to those of a traditional PBT plastic single material, the junction temperature of the SiC power device can be remarkably increased, the electric leakage risk caused by aging of the insulating layer between the DC1 power terminal and the DC2 power terminal is reduced, and the service life of the SiC power device is prolonged. The insulation stability between the two is improved, and the requirements of long-term high-temperature-resistant service in different application scenes are met.

Description

Technical Field

[0001] This utility model relates to the technical field of housings for SiC power devices, specifically a high-temperature resistant housing structure for SiC power devices. Background Technology

[0002] Existing SiC power devices consist of a plastic frame, AC power terminals, DC1 power terminals, and DC2 power terminals. The plastic frame is typically made of PBT (polypropylene) through injection molding. The AC, DC1, and DC2 power terminals are generally made of copper substrate, with surface finishes including bare copper, nickel plating, tin plating, silver plating, and gold plating. After the DC1 and DC2 power terminals are assembled and fixed to the plastic frame, they are insulated by the plastic frame itself. This has the following drawbacks in use:

[0003] (Existing plastic frame structures for SiC power device housings can meet the requirements of applications with junction temperatures below 150°C. As the demand for high power density in end-use applications (such as new energy vehicles, photovoltaic inverters, energy storage, and charging piles) continues to increase, the junction temperature of SiC power devices is being pushed from 150°C to 175°C or even 200°C.) However, existing housing structures for SiC power devices cannot meet the requirements for long-term high-temperature resistance. With the extension of service time, the plastic frame will age faster at high temperatures, leading to a decrease in the insulation performance of the DC1 power terminal and the DC2 power terminal, resulting in leakage risk and causing SiC power device failure. The insulation stability between the DC1 power terminal and the DC2 power terminal is not ideal. In view of this, this application proposes a high-temperature resistant housing structure for SiC power devices to solve the above-mentioned problems. Utility Model Content

[0004] The purpose of this invention is to provide a high-temperature resistant housing structure for SiC power devices to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high-temperature resistant housing structure for SiC power devices, comprising a plastic frame, wherein three AC power terminals are integrally injection molded and fixed at the bottom of the plastic frame, and three DC1 power terminals and three DC2 power terminals are integrally injection molded and fixed at the top of the plastic frame.

[0006] The three DC1 power terminals and the three DC2 power terminals are arranged alternately, and an insulating layer is pre-installed between the DC1 power terminals and the corresponding three DC2 power terminals.

[0007] Preferably, the insulating layer is one of PPA, PPS and insulating ceramic materials.

[0008] Preferably, the bottom of the DC1 power terminal is integrally provided with a first termination portion, and the bottom of the DC2 power terminal is integrally provided with two second termination portions. The first termination portion is located in the middle front side of the corresponding two second termination portions, and the insulating layer is located between the corresponding two second termination portions and the first termination portion.

[0009] Preferably, positioning holes are provided on the bottom front side of both the DC1 power terminal and the bottom front side of both the DC2 power terminal, and positioning protrusions are fixedly connected to the front and rear sides of the insulating layer, with the positioning protrusions being movably engaged in the corresponding positioning holes.

[0010] Preferably, the front side of the insulating layer has a front groove that can be movably fitted onto the bottom of the outer side of the DC1 power terminal, and the rear side of the insulating layer has a rear groove that can be movably fitted onto the bottom of the outer side of the DC2 power terminal.

[0011] Preferably, the plastic frame is provided with three rectangular spaces, which are located between the corresponding DC1 power terminal, DC2 power terminal and AC power terminal.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. By using a plastic frame, DC1 power terminal, DC2 power terminal and AC power terminal to be injection molded as a whole, the phenomenon of separate assembly and reserved terminal plug holes is eliminated, and the integrated stability effect is better.

[0014] 2. Furthermore, the insulation layer prefabrication is used to pre-position and separate the DC1 power terminal and DC2 power terminal through clamping and insulation. Since the insulation layer is one of PPA, PPS and insulating ceramic materials, the use of PPA, PPS or insulating ceramic materials as high temperature resistant insulation prefabrication materials is superior to the traditional single material PBT plastic in terms of high temperature resistance and insulation. This can significantly increase the junction temperature of SiC power devices, reduce the risk of leakage caused by the aging of the insulation layer between DC1 power terminal and DC2 power terminal, improve the insulation stability between them, and meet the requirements of long-term high temperature service in different application scenarios.

[0015] This invention utilizes a plastic frame, DC1 power terminal, DC2 power terminal, and AC power terminal to achieve integrated injection molding, eliminating the need for separate assembly and pre-reserved terminal insertion holes. This results in a more stable and integrated design. Furthermore, pre-fabricated insulating layers made of PPA, PPS, or insulating ceramic are used to pre-position and separate the DC1 and DC2 power terminals, providing superior high-temperature resistance and insulation compared to traditional single-material PBT plastic. This significantly increases the junction temperature of SiC power devices, reduces the risk of leakage due to insulation aging, and improves the insulation stability between the two components, meeting the requirements for long-term high-temperature service in various application scenarios. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a high-temperature resistant housing structure for SiC power devices proposed in this utility model;

[0017] Figure 2 This is a schematic diagram of the DC1 power terminal, DC2 power terminal and insulating layer connection structure of a high-temperature resistant housing structure for SiC power devices proposed in this utility model.

[0018] In the figure: 1. Plastic frame; 101. AC power terminal; 102. DC1 power terminal; 1021. First termination part; 1022. Positioning hole; 103. DC2 power terminal; 1031. Second termination part; 104. Insulating layer; 1041. Positioning protrusion. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] like Figures 1 to 2 As shown in the figure, the high-temperature resistant housing structure for SiC power devices proposed in this embodiment includes a plastic frame 1. The bottom of the plastic frame 1 is integrally injection molded and fixed with three AC power terminals 101, and the top of the plastic frame 1 is integrally injection molded and fixed with three DC1 power terminals 102 and three DC2 power terminals 103. By using the integral injection molding of the plastic frame 1, DC1 power terminals 102, DC2 power terminals 103 and AC power terminals 101, the phenomenon of separate assembly and reserved terminal plug-in holes is eliminated, and the integral injection molding has a better integral stability effect.

[0021] Three DC1 power terminals 102 and three DC2 power terminals 103 are arranged alternately, and an insulating layer 104 is pre-installed between the DC1 power terminals 102 and the corresponding three DC2 power terminals 103.

[0022] Specifically, the insulating layer 104 is one of PPA, PPS and insulating ceramic materials; using PPA, PPS and insulating ceramic materials as high temperature resistant insulating preforms, and taking advantage of their superior high temperature resistance and insulation compared to traditional single PBT plastic materials, can significantly increase the junction temperature of SiC power devices and reduce the risk of leakage caused by the aging of the insulating layer 104 between DC1 power terminal 102 and DC2 power terminal 103.

[0023] Furthermore, the bottom of the DC1 power terminal 102 is integrally provided with a first termination portion 1021, and the bottom of the DC2 power terminal 103 is integrally provided with two second termination portions 1031. The first termination portion 1021 is located on the front side of the middle of the two corresponding second termination portions 1031, and the insulating layer 104 is located between the two corresponding second termination portions 1031 and the first termination portion 1021.

[0024] Furthermore, positioning holes 1022 are provided on the bottom front side of both the DC1 power terminal 102 and the DC2 power terminal 103. Positioning protrusions 1041 are fixedly connected to the front and rear sides of the insulating layer 104, and the positioning protrusions 1041 are movably engaged in the corresponding positioning holes 1022. A front groove is provided on the front side of the insulating layer 104 that is movably engaged in the bottom outer side of the DC1 power terminal 102, and a rear groove is provided on the rear side of the insulating layer 104 that is movably engaged in the bottom outer side of the DC2 power terminal 103. The positioning holes 1022 and the positioning protrusions 1041, together with the front and rear grooves respectively engaged in the bottom outer side of the DC1 power terminal 102 and the DC2 power terminal 103, serve to position and prevent displacement of the DC1 power terminal 102 and the DC2 power terminal 103 before injection molding.

[0025] Furthermore, the plastic frame 1 is provided with three rectangular spaces, which are located between the corresponding DC1 power terminal 102, DC2 power terminal 103 and AC power terminal 101.

[0026] The usage method of this embodiment is as follows: Before integral injection molding, firstly, the DC1 power terminal 102 is snapped into the front groove on the front side of the insulating layer 104, and the positioning hole 1022 on the DC1 power terminal 102 is fitted onto the outside of the front positioning protrusion 1041. Then, the DC2 power terminal 103 is snapped into the rear groove on the rear side of the insulating layer 104, and the positioning hole 1022 on the DC2 power terminal 103 is fitted onto the outside of the rear positioning protrusion 1041. This forms an integral effect where the insulating layer 104, DC1 power terminal 102, and DC2 power terminal 103 are snapped and positioned. The insulating layer 104 acts as a separator and insulator between the DC1 power terminal 102 and DC2 power terminal 103. Then, the integrally formed by snapping and the AC power terminal 101 can be placed into the corresponding position of the external injection mold for injection molding. After injection molding, the plastic frame formed is integrated with the insulating layer 104 and the DC1 power terminal 103. The DC1 power terminal 102, DC2 power terminal 103, and AC power terminal 101 are fixedly integrated into one unit. By using the plastic frame 1, the DC1 power terminal 102, DC2 power terminal 103, and AC power terminal 101 are integrally injection molded, eliminating the need for separate assembly and pre-reserved terminal insertion holes. Furthermore, the integral injection molding provides better overall stability. Since the insulation layer 104 is made of PPA, PPS, or insulating ceramic, using PPA, PPS, or insulating ceramic as high-temperature resistant insulating prefabricated components offers superior high-temperature resistance and insulation compared to traditional single-material PBT plastic. This significantly increases the junction temperature of SiC power devices, reduces the risk of leakage due to aging of the insulation layer 104 between the DC1 power terminal 102 and DC2 power terminal 103, and improves the insulation stability between the DC1 and DC2 power terminals, meeting the requirements for long-term high-temperature service in various application scenarios.

[0027] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A high-temperature resistant housing structure for SiC power devices, comprising a plastic frame (1), characterized in that: The bottom of the plastic frame (1) is integrally injection molded and fixed with three AC power terminals (101), and the top of the plastic frame (1) is integrally injection molded and fixed with three DC1 power terminals (102) and three DC2 power terminals (103). The three DC1 power terminals (102) and the three DC2 power terminals (103) are arranged alternately, and an insulating layer (104) is pre-installed between the DC1 power terminals (102) and the corresponding three DC2 power terminals (103).

2. The high-temperature resistant housing structure for SiC power devices according to claim 1, characterized in that: The insulating layer (104) is one of PPA, PPS and insulating ceramic materials.

3. The high-temperature resistant housing structure for SiC power devices according to claim 2, characterized in that: The bottom of the DC1 power terminal (102) is integrally provided with a first termination portion (1021), and the bottom of the DC2 power terminal (103) is integrally provided with two second termination portions (1031). The first termination portion (1021) is located in the middle front side of the corresponding two second termination portions (1031), and the insulating layer (104) is located between the corresponding two second termination portions (1031) and the first termination portion (1021).

4. The high-temperature resistant housing structure for SiC power devices according to claim 1, characterized in that: Positioning holes (1022) are provided on the bottom front side of the DC1 power terminal (102) and the bottom front side of the DC2 power terminal (103). Positioning protrusions (1041) are fixedly connected to the front and rear sides of the insulating layer (104), and the positioning protrusions (1041) are movably locked in the corresponding positioning holes (1022).

5. The high-temperature resistant housing structure for SiC power devices according to claim 4, characterized in that: The front side of the insulating layer (104) has a front groove that can be movably fitted onto the bottom of the outer side of the DC1 power terminal (102), and the rear side of the insulating layer (104) has a rear groove that can be movably fitted onto the bottom of the outer side of the DC2 power terminal (103).

6. The high-temperature resistant housing structure for SiC power devices according to claim 1, characterized in that: The plastic frame (1) has three rectangular spaces located between the corresponding DC1 power terminal (102), DC2 power terminal (103), and AC power terminal (101).

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