Vehicle-mounted PFC boost inductor of new energy automobile

Abstract

The utility model discloses a new energy automobile vehicle-mounted PFC boost inductor, and belongs to the new energy automobile power drive and photovoltaic boost inductor technical field, a skeleton fixing sensing structure comprises a leading-out terminal copper bar, a thermosetting resin skeleton, a fixing nut and an NTC temperature sensor, an injection molding insulation layer is higher in compactness and free of air holes, and the safety of the whole structure is improved. On the premise that the safety requirement is met, the safety distance between the coil and the magnetic core can be shortened, so that the size of the inductor is reduced, the vehicle-mounted boost inductor framework prepared through the integrated injection molding technology is high in structural strength, the vehicle-mounted boost inductor framework is fixed to a vehicle system through the injection molding framework, and the working environment of strong vibration of a vehicle can be met; the technology is simple, automation is easier to achieve, the production cost can be reduced, the boost inductor adopts one or more of low-loss iron silicon, iron silicon aluminum or iron nickel as the magnetic core, the resin for injection molding has good heat dissipation performance, and the working temperature can be 125 DEG C or below under the large-current and high-voltage condition.

Description

Technical Field

[0001] The utility model relates to a vehicle-mounted PFC boost inductor for new energy vehicles, belonging to the technical fields of power drive of new energy vehicles and photovoltaic boost inductors. Background Art

[0002] The explosive growth in the demand for new energy vehicles; with the strong support of national policies, downstream vehicle enterprises have increased their efforts in developing new energy business, promoting the launch of high-quality new energy vehicle models, improving the cruising range, optimizing the intelligent driving experience, and further improving supporting facilities. The consumer demand has increased significantly. The sales volume of new energy vehicles in 2022 was 6.887 million, and the ownership of new energy vehicles reached 16.2 million in the first half of 2023, with a year-on-year increase of nearly 53%. Currently, most of the existing DC fast charging infrastructure basically serves 400V vehicles. Therefore, if we want to complete the ecological construction of the 800V platform, in addition to upgrading the in-vehicle accessories, we also need to support corresponding charging facilities externally. Among them, the in-vehicle accessories include components such as the core three-electric system, air conditioner compressor, DCDC (DC transformer), and OBC (on-board charger), and the external support is charging piles and charging stations, etc.

[0003] For example, the vehicle-mounted PFC inductor disclosed in the application number: 202321329678.5 includes a bottom plate, a toroidal magnetic core, a limiting component, and a coil winding. Among them, the toroidal magnetic core is arranged on the bottom plate, and the bottom of the toroidal magnetic core is fixedly connected to the bottom plate; the bottom plate is provided with a limiting component outside the toroidal magnetic core, and the limiting component abuts against the toroidal magnetic core. The limiting component is used to position the toroidal magnetic core in a direction parallel to the bottom plate; the coil winding is wound around the toroidal magnetic core, and the fixed structure of the toroidal magnetic core is improved to achieve effective positioning and stable installation of the toroidal magnetic core, so that the internal structure of the vehicle-mounted PFC inductor can adapt to the vibration conditions of vehicle-mounted products and meet the strict requirements of vehicle-mounted products for installation firmness.

[0004] Based on retrieval and analysis, the deficiencies of the existing technology are found:

[0005] There is little research on vehicle-mounted PFC boost inductors for new energy vehicles in the market, and products with advanced processes and designs of advanced boost inductors for new energy vehicles are all in the hands of enterprises in Japan, the United States, etc. Under this background, the present invention has developed a pfc boost inductor that can meet the applications in fields such as new energy electric vehicles and photovoltaics. The present invention provides a new method for preparing vehicle-mounted boost inductors, and all aspects of its performance are close to the relevant products studied abroad, with a relatively low operating temperature and can be used in the vehicle-mounted power drive module of new energy vehicles.

[0006] The application of electronic components in the field of new energy vehicles needs to consider the impact of harsh automotive environments such as oil stains and dust on inductors, as well as the radiation interference from surrounding components and the strong vibrations during vehicle operation. It is necessary to fix the inductor and provide protection such as dust and moisture prevention to improve its performance and reliability. For the boost inductor used in internal components, potting glue or one-piece injection molding processes can be adopted. Although the potting glue process is simple and feasible, it also exposes some disadvantages, such as being prone to generating bubbles, which pose significant hidden dangers in aspects such as the insulation safety performance of the boost inductor. Therefore, a vehicle-mounted PFC boost inductor for new energy vehicles is required as a boost component in the on-vehicle charger of the 800V boost platform. Therefore, a vehicle-mounted PFC boost inductor for new energy vehicles is needed to improve the above deficiencies. Summary of the Invention

[0007] The main purpose of the present invention is to provide a vehicle-mounted PFC boost inductor for new energy vehicles.

[0008] The purpose of the present invention can be achieved by adopting the following technical solutions:

[0009] A vehicle-mounted PFC boost inductor for new energy vehicles includes an aluminum alloy heat dissipation base for heat conduction;

[0010] The aluminum alloy heat dissipation base is covered with a heat conduction pad, on which a plastic insulation skeleton is installed. A magnetic core is installed inside the plastic insulation skeleton. The plastic insulation skeleton is made of injection-molded thermosetting resin. A coil is wound around the plastic insulation skeleton, and the coil is wound by flat copper wire;

[0011] Skeleton fixing sensing structures are respectively installed on both sides of the flat copper wire.

[0012] Preferably, the skeleton fixing sensing structure includes a lead-out terminal copper bar, a thermosetting resin skeleton, a fixing nut, and an NTC temperature sensor;

[0013] A lead-out terminal copper bar is installed on one side of the flat copper wire, a fixing nut is installed on one side of the lead-out terminal copper bar, the fixing nut is fixed on the thermosetting resin skeleton, and an NTC temperature sensor is installed at the other end of the plastic insulation skeleton.

[0014] Preferably, the flat copper wire, the heat conduction pad, the thermosetting resin skeleton, the fixing nut, the lead-out terminal copper bar, the aluminum alloy heat dissipation base, the plastic insulation skeleton, and the NTC temperature sensor are formed by injection molding in an integrated manner.

[0015] Preferably, the magnetic core is pressed from low-loss iron silicon powder, iron silicon aluminum powder, and carbonyl iron powder.

[0016] Preferably, the resin for the injection-molded thermosetting resin and the thermosetting resin skeleton is PBS resin, phenolic resin, epoxy resin, polyimide resin, polytetrafluoroethylene (PTFE), or BT resin. The processing temperature of the injection-molded thermosetting resin and the thermosetting resin skeleton is 140 - 260 °C.

[0017] Preferably, the resin molding processing temperature of the injection-molded thermosetting resin and the thermosetting resin skeleton is 140 - 260 °C, the injection pressure is 45 - 90 Mpa, and the holding pressure time is 12 - 18 s.

[0018] The beneficial technical effects of the present utility model:

[0019] A vehicle-mounted PFC boost inductor for new energy vehicles provided by the present utility model

[0020] 1. The injection-molded insulating layer has a higher density and no air holes. On the premise of meeting the safety regulations requirements, the safety distance between the coil and the magnetic core can be shortened, thereby reducing the volume of the inductor.

[0021] 2. The vehicle-mounted boost inductor skeleton prepared by the one-piece injection molding process has high structural strength. It is fixed to the vehicle system through the injection-molded skeleton, which can meet the working environment of strong vibrations in the vehicle. Moreover, this process is simple and easier to automate, which can reduce its production cost.

[0022] 3. The boost inductor uses one or more of low-loss iron-silicon, iron-silicon-aluminum, or iron-nickel as the magnetic core, and the resin for injection molding has good heat dissipation. The working temperature can be below 125 °C under the conditions of high current and high voltage. Description of the Drawings

[0023] Figure 1 It is a schematic diagram of the boost inductor structure according to a preferred embodiment of a vehicle-mounted PFC boost inductor for new energy vehicles of the present utility model;

[0024] Figure 2 It is an exploded schematic diagram of the boost inductor structure according to a preferred embodiment of a vehicle-mounted PFC boost inductor for new energy vehicles of the present utility model.

[0025] In the figure: 1, magnetic core; 2, plastic insulation skeleton; 3, coil; 4, injection-molded thermosetting resin; 5, aluminum alloy heat dissipation base; 6, heat conduction pad; 7, lead-out terminal copper bar; 8, flat copper wire; 9, thermosetting resin skeleton; 10, fixing nut; 11, NTC temperature sensor. Detailed Embodiments

[0026] To make the technical solution of the present utility model clearer and more definite for those skilled in the art, the present utility model will be further described in detail below in conjunction with embodiments and drawings, but the implementation manners of the present utility model are not limited thereto.

[0027] As Figure 1 - Figure 2 shown, a vehicle-mounted PFC boost inductor for a new energy vehicle provided in this embodiment includes an aluminum alloy heat dissipation base 5 for heat conduction;

[0028] The aluminum alloy heat dissipation base 5 is covered with a heat conduction pad 6, a plastic insulation skeleton 2 is installed on the heat conduction pad 6, a magnetic core 1 is installed inside the plastic insulation skeleton 2, the plastic insulation skeleton 2 is made of an injection-molded thermosetting resin 4, and a coil 3 is wound around the plastic insulation skeleton 2; the coil 3 is wound by flat copper wires 8;

[0029] Skeleton fixing and sensing structures are respectively installed on both sides of the flat copper wire 8.

[0030] The skeleton fixing and sensing structures include a lead-out terminal copper bar 7, a thermosetting resin skeleton 9, a fixing nut 10, and an NTC temperature sensor 11;

[0031] A lead-out terminal copper bar 7 is installed on one side of the flat copper wire 8, a fixing nut 10 is installed on one side of the lead-out terminal copper bar 7, the fixing nut 10 is fixed on the thermosetting resin skeleton 9, and an NTC temperature sensor 11 is installed at the other end of the plastic insulation skeleton 2.

[0032] The flat copper wire 8, the heat conduction pad 6, the thermosetting resin skeleton 9, the fixing nut 10, the lead-out terminal copper bar 7, the aluminum alloy heat dissipation base 5, the plastic insulation skeleton 2, and the NTC temperature sensor 11 are formed by an injection-molded integral molding method.

[0033] The magnetic core 1 is made by pressing low-loss iron silicon powder, iron silicon aluminum powder, and carbonyl iron powder.

[0034] The injection-molded thermosetting resin 4 and the thermosetting resin skeleton 9 adopt resins such as PBS resin, phenolic resin (Phenolic), epoxy resin (Epoxy), polyimide resin (Polyimide), polytetrafluoroethylene (PTFE), or BT resin (BT), and the processing temperature of the injection-molded thermosetting resin 4 and the thermosetting resin skeleton 9 is 140 - 260 °C.

[0035] The resin molding processing temperature of the injection-molded thermosetting resin 4 and the thermosetting resin skeleton 9 is 140 - 260 °C, the injection pressure is 45 - 90 Mpa, and the holding pressure time is 12 - 18 s.

[0036] As Figure 1 - Figure 2As shown in the figure, the working process of a vehicle-mounted PFC boost inductor provided in this embodiment is as follows: Before the process injection molding, the preheating temperature of the assembled inductor is 130°C, the resin molding processing temperature is 140 - 260°C, the injection molding pressure is 45 - 90 Mpa, the holding pressure time is 12 - 18 s, and the welding requirements for welding the copper busbar using argon arc welding technology are as follows: 1. The surface of the welding part is bright and free of burrs; 2. There are no black spots at the welding part; 3. The unpainted part of the pin does not turn black; 4. The welding depth is greater than 1.0 - 3.0 mm. The air shower ultrasonic cleaning steps mainly include: ① Ultrasonic cleaning of the copper busbar inductor assembly, cleaning duration: 3 - 5 min; ② Blowing dry for 1 min; ③ Drying: temperature: 80 ± 10°C, drying duration 30 min; ④ Cooling to room temperature. After the boost inductor is installed with an NTC temperature sensor and tested qualified, it is packaged. The inductor uses flat wound coils neatly arranged symmetrically on both sides. The middle magnetic core is in a strip shape with an air gap opened. The magnetic cores 1 at both ends adopt a U-shaped structure, and the arc surface is located on the outer circular contour of an annular inductor of the same size. Therefore, the effective cross-sectional area of the magnetic core 1 of the inductor will increase significantly, and the space occupancy rate of the coil 3 will increase greatly, so that the space utilization rate of the coil 3 and the magnetic core 1 of the inductor will increase significantly, far exceeding the space utilization rate of the magnetic core material and the winding coil 3 of the annular vertical wound inductor. Therefore, the inductance of the inductor is also greater than that of the annular inductor. When in use, take this inductor and fix it on the heat dissipation base during installation. During the use process, part of the heat generated by the inductor will be dissipated through itself, and at the same time, the heat dissipation pad and the base will also dissipate heat together. The coil 3 adopts a square design structure, which increases the heat dissipation area of the inductor body compared with the annular design, and has a better heat dissipation effect. The effective area of the middle column of the magnetic core 1 will also increase, which can increase its inductance and further reduce the design size. The magnetic core used for this boost inductor is a magnetic core 1 pressed by low-loss iron silicon powder, iron silicon aluminum powder, carbonyl iron powder, or several of these powders. The injection molding resin material uses PBS resin, phenolic resin (Phenolic), epoxy resin (Epoxy), polyimide resin (Polyimide), polytetrafluoroethylene (PTFE), or B-trinitride resin (BT), or one of these resins, and the processing temperature is 140 - 260°C.

[0037] Embodiment

[0038] As Figure 1 - Figure 2 As shown in the figure, before the process injection molding, the preheating temperature of the assembled inductor is 130°C, the resin molding processing temperature is 140 - 260°C, the injection molding pressure is 45 - 90 Mpa, the holding pressure time is 12 - 18 s, and the welding requirements for welding the copper busbar using argon arc welding technology are as follows: 1. The surface of the welding part is bright and free of burrs; 2. There are no black spots at the welding part; 3. The unpainted part of the pin does not turn black; 4. The welding depth is greater than 1.0 - 3.0 mm;

[0039] The steps of air shower ultrasonic cleaning mainly include: ① ultrasonic cleaning of the copper busbar inductor assembly, cleaning time: 3 to 5 minutes; ② blow dry for 1 minute; ③ drying: temperature: 80±10℃, drying time: 30 minutes; ④ cooling to room temperature.

[0040] After the boost inductor is installed with the NTC temperature sensor, it is tested and packaged.

[0041] The flat vertically wound coils of the inductor are neatly arranged symmetrically on both sides, the middle magnetic core is in strip shape with an air gap, and the magnetic cores 1 at both ends are in U-shaped structure, and the arc surface is located on the outer circular contour of the toroidal inductor of the same size. Therefore, the effective cross-sectional area of ​​the magnetic core 1 of the inductor will be significantly increased, and the space occupancy rate of the coil 3 will be greatly improved, so that the space utilization rate of the coil 3 and the magnetic core 1 of the inductor is greatly increased, which far exceeds the space utilization rate of the magnetic core material and the winding coil 3 of the toroidal vertically wound inductor. Therefore, the inductance of the inductor is also greater than the inductance of the toroidal inductor.

[0042] When using, take out the inductor and fix it on the heat dissipation base when installing it. During use, part of the heat generated by the inductor will be discharged through itself, and the heat dissipation pad and the base will also dissipate heat together. The square design structure of the coil 3 increases the heat dissipation area of ​​the inductor body compared to the ring design, and the heat dissipation effect is better. The effective area of ​​the middle column of the magnetic core 1 will also increase, which can increase its inductance and further reduce the design size;

[0043] The magnetic core used in the boost inductor is a magnetic core 1 pressed by low-loss iron silicon powder, sendust powder or carbonyl iron powder or several of them. The injection molding resin material adopts PBS resin, phenolic resin (Phenolic), epoxy resin (Epoxy), polyimide resin (Polyimide), polytetrafluoroethylene (PTFE) or B-triazine resin (BT) or one of them, and the processing temperature is 140-260°C.

[0044] The above is only a further embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the scope disclosed by the present invention according to the technical solution and concept of the present invention, which fall within the protection scope of the present invention.

Claims

1. A PFC boost inductor for a new energy vehicle, comprising an aluminum alloy heat sink base (5) for heat conduction; Features: The aluminum alloy heat dissipation base (5) is covered with a heat conductive pad (6), a plastic insulating frame (2) is installed on the heat conductive pad (6), a magnetic core (1) is installed in the plastic insulating frame (2), the plastic insulating frame (2) is made of injection-molded thermosetting resin (4), a coil (3) is wound on the plastic insulating frame (2), and the coil (3) is wound by a flat copper wire (8); Frame-fixed sensing structures are respectively installed on both sides of the flat copper wire (8).

2. The PFC boost inductor for new energy vehicles according to claim 1, characterized in that: The frame-fixed sensing structure comprises a lead-out copper bar (7), a thermosetting resin frame (9), a fixing nut (10) and an NTC temperature sensor (11); A lead-out copper bar (7) is installed on one side of the flat copper wire (8), a fixing nut (10) is installed on one side of the lead-out copper bar (7), the fixing nut (10) is fixed on a thermosetting resin frame (9), and an NTC temperature sensor (11) is installed on the other end of the plastic insulation frame (2).

3. The PFC boost inductor for new energy vehicles according to claim 2, characterized in that: The flat copper wire (8), the thermal pad (6), the thermosetting resin frame (9), the fixing nut (10), the lead-out copper busbar (7), the aluminum alloy heat dissipation base (5), the plastic insulation frame (2) and the NTC temperature sensor (11) are prepared by integral injection molding.

4. The PFC boost inductor for new energy vehicles according to claim 3 is characterized in that: The magnetic core (1) is formed by pressing low-loss iron silicon powder, sendust powder and carbonyl iron powder.

5. The PFC boost inductor for new energy vehicles according to claim 4, characterized in that: The injection molding thermosetting resin (4) and the thermosetting resin skeleton (9) use PBS resin, phenolic resin (Phenolic), epoxy resin (Epoxy), polyimide resin (Polyimide), polytetrafluoroethylene (PTFE) or B-triazine resin (BT) resin, and the processing temperature of the injection molding thermosetting resin (4) and the thermosetting resin skeleton (9) is 140-260°C.

6. The PFC boost inductor for new energy vehicles according to claim 5, characterized in that: The resin molding processing temperature of the injection-molded thermosetting resin (4) and the thermosetting resin skeleton (9) is 140-260° C., the injection pressure is 45-90 MPa, and the holding time is 12-18 seconds.

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