HIGH-VOLTAGE TEMPERATURE MEASURING ARRANGEMENT AND CHARGING CONNECTOR AND ELECTRIC VEHICLE THEREFORE

Abstract

The invention relates to a high-voltage temperature measuring arrangement for measuring the temperature of an electrically conductive component during operation with high voltage, wherein the high-voltage measuring device comprises: the electrically conductive component and a temperature measuring device with a temperature sensor, wherein the temperature measuring device is sintered onto at least a portion of the component for thermally conductive connection to the component.

Description

TECHNICAL FIELD

[0001] The present invention relates to a high-voltage temperature measuring arrangement. The invention further relates to a high-voltage charging connector with at least one such high-voltage temperature measuring arrangement and to an electric vehicle with at least one such high-voltage temperature measuring arrangement. BACKGROUND OF THE INVENTION

[0002] High-voltage applications are used, for example, in electric vehicles and dedicated charging connectors such as charging plugs. The high electrical voltages and, for example, high charging power when charging batteries often require complex electrical insulation or lead to significant thermal stress. Temperature measurement is therefore often used in high-voltage interfaces to protect surrounding components and contact parts from thermal overload. Furthermore, temperature measurement can warn of critical abnormalities, such as contact wear and contact oxidation, which can result in increased connection resistance.However, problems often occur in connection with temperature sensors for such interfaces, such as undesired loosening of the fastening of the temperature sensors, limited thermal loads due to the fastening, for example solder, or insulation faults.

[0003] It is therefore desirable to create a reliable temperature measurement and monitoring system for high-voltage contacts with little effort and low cost. SUMMARY OF THE INVENTION

[0004] The invention relates to a high-voltage temperature measuring arrangement for measuring the temperature of an electrically conductive component during operation with high voltage, wherein the high-voltage temperature measuring arrangement comprises the electrically conductive component, a temperature measuring device with a temperature sensor, an electrically insulating material, and a printed circuit board, wherein the temperature measuring device is thermally conductively connected to the electrically conductive component by sintering, wherein the printed circuit board is arranged at a distance from the electrically conductive component and is electrically and directly or indirectly mechanically connected to the temperature sensor for transmitting measuring signals, and the electrically insulating material surrounds at least the temperature measuring device at least in sections.

[0005] It can be a high-voltage temperature measuring arrangement of an electrically conductive component, in particular a high-voltage contact or a high-voltage interface between two electrically conductive contact parts that are subjected to high voltage and electrically connected by the electrically conductive component. This interface can be located in the charging path between the charging interface and the battery, in particular in the charging socket, in the traction path between the battery and the electric drive, or in other high-voltage paths between the battery and other electrical components.

[0006] According to the invention, the electrically conductive component and the temperature measuring device, in particular a section of the ceramic body of the temperature measuring device, are connected by sintering. This means that there is a material bond between the component and the temperature measuring device, in particular the ceramic body, which was achieved by the heat input during sintering. In other words, the temperature measuring device is sintered onto the electrically conductive component. In particular, sintering involves a regrouping at the molecular level, which creates the connection between the component and the second surface area. Sintering can be carried out with or without pressure. The sintering process can be referred to as so-called silver sintering. According to the criteria of DIN 1910, the sintering process can be categorized as a diffusion welding process. A sintering paste with a high silver content can be used to create the bond.The process can proceed as follows: (1) paste application, especially by stencil printing, (2) pre-drying, (3) positioning of the components to each other, (4) (pressure) sintering (e.g. at 150 to 300°C; at 0 to 25 MPa; during t = 2 - 5 min).

[0007] The temperature measuring device is thus connected to the electrically conductive component, which is subjected to high voltage. The temperature measuring device is electrically insulated from the electrically conductive component (by the ceramic body), but is thermally conductively connected to the electrically conductive component in order to detect its temperature. This is made possible by the ceramic body, which is thermally conductive but not electrically conductive.

[0008] The electrically insulating material in the sense of the present invention can be realized as a casting compound and / or as a sheath.

[0009] Due to the inherent material properties of ceramic materials, the ceramic body can exhibit particularly high electrical insulation capacity despite a relatively low component thickness. At the same time, the ceramic body can be designed as a thermally conductive technical ceramic, i.e., one optimized for thermal conduction. The ceramic body can thus have a thermal conductivity of at least 10 W / (m K), preferably of at least 20 W / (m K). For example, an Al2O3 ceramic or the like can be used, thus achieving a good compromise between the highest possible thermal conductivity and the lowest possible cost. The ceramic body can therefore simultaneously provide both the electrical insulation between the temperature sensor and the component, which may be carrying high voltage during operation, and the thermal or heat-conducting connection of the temperature sensor to the component.This can thus enable a particularly reliable, yet particularly simple and compact design of the temperature measuring arrangement and the interface as a whole. Furthermore, the interface design proposed here can enable or achieve particularly accurate and dynamic temperature monitoring—i.e., one that reacts particularly quickly and precisely to temperature changes in the component—for example, compared to positioning a temperature sensor or the like further away from the component. The ceramic body can be relatively inexpensive. The ceramic body can have dimensions in the millimeter range, e.g., 3.0 x 1.5 x 0.5 mm.

[0010] The first and second surface regions are electrically insulated from each other by at least a portion of the ceramic body. The first and second surface regions are preferably spaced apart from each other, more preferably arranged on opposite sides of the ceramic body.

[0011] By measuring the temperature at the interface, i.e., the component, an abnormality or fault can be detected quickly, especially while avoiding a sensor time delay. For example, if the temperature rises, the current can be reduced, known as de-rating. Additionally or alternatively, aging processes can be detected. This can improve the reliability of temperature monitoring and, consequently, the overall reliability of an electric vehicle.

[0012] The interface can be designed as a plug-in system or a screw system.

[0013] The component can establish an electrical connection between two contact parts arranged on different sides of the component. For example, a mechanical connection of the two contact parts to the component is provided. In a preferred embodiment, the component can be designed as a rail and connect cable lugs as contact parts.

[0014] The electrical component can be, for example, a busbar, a contact part, a contact pin, or a contact socket. The interface can be located in a charging connector (charging socket) as a charging contact and referred to as a charging pin. The high-voltage charging connector can, in particular, be a high-voltage or high-voltage charging socket, particularly for a motor vehicle. The charging contact or charging pin can be designed as an electrical connection or contact element via which a corresponding voltage or current can be provided or conducted.

[0015] The terms “high voltage” or “high voltage” in the sense of the present invention can refer in particular to applications with or a design for electrical voltages of at least 48 V or at least 100 V or at least 200 V or at least 400 V or more, in particular at currents of several amperes.

[0016] The high-voltage temperature measuring device has a temperature sensor, in particular a low-voltage temperature sensor, which is used to measure the temperature at the interface or component. The operating voltage of the sensor is lower than the high voltage provided or capable of being delivered via the interface during intended operation. For example, the temperature sensor can be configured or designed for an operating voltage of less than 48 V, for example, 12 V or less. This operating voltage can be a supply voltage and / or a working or measuring voltage of the temperature sensor.

[0017] The temperature measuring device according to the invention is sinterable. For this purpose, the temperature measuring device is preferably designed such that the temperature sensor is applied to the ceramic body and the ceramic body is bonded to the component during sintering. In particular, a copper rail as a component (by means of DCB, direct copper bonded) is envisaged for this. The temperature measuring device is arranged in particular as an SMD component (SMD: surface-mounted device) on a side or surface of the ceramic part facing away from the component, on or at the latter. The ceramic body can therefore be arranged, for example, in direct or immediate contact with a surface or outer side of the temperature measuring device. This makes it possible to achieve a particularly low heat transfer resistance or a particularly large-area heat-conducting contact between the ceramic body and the component. The temperature sensor can, for example,a sinterable SMD 1206 SC sensor.

[0018] The temperature sensor is preferably designed to be substantially planar, in particular for planar connection to the first surface region of the ceramic body.

[0019] Preferably, the second surface area is metallized for connection to the component and / or there is sintering paste between the second surface area and the component. The sintering process can be carried out using a sintering paste that is applied between the second surface of the ceramic body and the component. Unlike an adhesive, the sintering paste consists of silver, copper, titanium, etc. It can therefore have a much higher thermal conductivity than many adhesives. The sintering paste can in particular contain silver. This can be so-called “silver sintering”. One advantage of silver can be that it can be used across the entire high-voltage application range, in particular up to temperatures of 200 °C. A sintering paste can strengthen the connection during sintering. The thermal conductivity of the sintering paste can be at least 100 W / mK.Alternatively or additionally, the second surface area can be metallized prior to the sintering process to improve the bondability to the electrically conductive component. Otherwise, the sintering paste might not bond directly to the ceramic, i.e., the ceramic body.

[0020] According to the invention, the arrangement further comprises a printed circuit board, which is arranged at a distance from the component and is connected to the temperature sensor for transmitting measurement signals. Measurement signals can thus be forwarded from the temperature sensor to the printed circuit board and then evaluated. The printed circuit board can be a PCB (printed circuit board) or FPC (flexible printed circuit). The printed circuit board can extend away from the component and / or be arranged at least partially on the casing.

[0021] One or more temperature sensors or one or more arrangements according to the invention can be connected to the same circuit board. More preferably, the connection between the circuit board and the temperature sensor(s) is made by means of at least one electrically conductive connection, for example, a wire bond or a spring contact. For example, an aluminum wire with a diameter of 100 to 500 µm can be used.

[0022] Preferably, the arrangement comprises an electrically insulating sheath that at least partially surrounds the electrically conductive component and / or at least partially surrounds the temperature measuring device at a distance therefrom. This can be an electrically insulating material within the meaning of claim 1.

[0023] The jacket can be in contact with the surface of the component, at least in sections. The jacket can be advantageous in terms of tracking resistance. In particular, tracking requirements can be better met. The jacket can comprise plastic and can be produced, for example, by injection molding or 3D printing. In one embodiment in which the jacket is produced by injection molding, the arrangement can be inserted into an injection mold and then overmolded with the jacket. If the jacket is produced by 3D printing, the jacket is manufactured separately and must then be attached to the component. In this case, the jacket can be designed, for example, as a clip that then grips the component. The clip can, for example, be designed in two pieces, with the two halves of the clip being screwed together.Preferably, the temperature measuring device is at least partially, and more preferably completely, free from the casing. When the casing is molded onto the component using the injection molding process, a gap between the casing and the temperature measuring device ensures that the temperature measuring device is not damaged. It is conceivable that one casing may at least partially contain multiple temperature measuring devices.

[0024] Preferably, the casing has at least one recess (relative to the surrounding casing) in which the temperature measuring device is arranged, at least in part. This allows the temperature measuring device to be protected by the casing. The recess can be designed as a cavity and represent a hollow space. In other words, the recess in the casing can be cup-shaped. The recess can have a surface area of approximately 100-150 mm 2 and, for example, a depth of 2-3 mm.

[0025] Preferably, the temperature sensor, preferably the temperature measuring device, is covered with at least one potting compound as an electrically insulating material. The potting compound can thus protect the temperature sensor, in particular the electrical connection that runs from the temperature sensor to the circuit board. Preferably, the potting compound is located at least partially in the recess in the casing. Further preferably, the potting compound can at least partially fill the recess in the casing and cover the temperature measuring device. This enables protection of the temperature sensor, wherein this protection includes the electrical connection to the circuit board and is therefore provided after the temperature sensor is connected to the circuit board. The potting compound can also serve to hermetically seal the temperature sensor, in particular the temperature measuring device, particularly in cooperation with the casing.This can prevent an unwanted air gap between the conductive component, the temperature sensor and the circuit board.

[0026] The potting compound can have a thermal expansion similar to that of ceramic or plastic. The potting compound can be designed to prevent gap formation, particularly given the different thermal expansion coefficients of the electrically conductive component, the temperature sensor, the connection, and the ceramic body. Polyurethane can be used as the potting compound. The thermal conductivity of the potting compound can be between 0.1 and 1 W / mK.

[0027] The invention further relates to a high-voltage charging connector with an arrangement according to the invention. The high-voltage charging connector can be a charging plug with at least one charging contact for connecting to an electrical contact of a charging port of an electric vehicle for charging the electric vehicle with high voltage, wherein the charging contact corresponds to the electrically conductive component or is electrically conductively connected to the electrically conductive component, and the charging connector has at least one arrangement according to one of the preceding claims. The charging connector can be the charging plug of an electric charging station. The charging contact can be designed as a charging pin. This allows the temperature of the contacts involved in charging the electric battery to be monitored. In particular, heating can occur during charging due to the high current output.

[0028] The invention further relates to an electric vehicle with a high-voltage interface. The interface can be located in the vehicle in the charging path between the charging interface and the battery, in the traction path between the battery and the electric drive, or in further high-voltage paths between the battery and further electrical units. The electric vehicle can be provided with at least one high-voltage interface that connects a first electrically conductive contact part, in particular a charging connection, to a second electrically conductive contact part, in particular an electrical contact of a high-voltage charging connector for charging the electric vehicle, wherein the first or second contact part electrically conductively connects an electrically conductive component to the other contact part, and the high-voltage interface has at least one high-voltage temperature measuring arrangement according to one of the preceding claims. The first and second contact parts can, for example,Cable lugs, where the electrically conductive component represents a rail that electrically connects the two contact parts.

[0029] Furthermore, the invention relates to a method for providing a high-voltage temperature measuring device on an electrically conductive component. The method is preferably used to manufacture the high-voltage temperature measuring arrangement according to the invention. The method comprises providing a (sinterable) temperature measuring device with a temperature sensor and preferably a ceramic body with a first and a second surface region, wherein the first surface region is thermally conductively connected to the temperature sensor for measuring the temperature of the first surface region, and sintering the temperature measuring device onto the component, whereby the second surface region is integrally connected to at least a portion of the electrically conductive component by heat input.

[0030] Preferably, the second surface area is metallized at least in sections before sintering and / or sintering paste is applied to the second surface area.

[0031] Preferably, after sintering, an electrically insulating jacket is applied which surrounds the conductive component at least in sections and / or surrounds the temperature measuring device at least in sections at a distance.

[0032] Preferably, after sintering, preferably after arranging the jacket, a printed circuit board is electrically conductively connected to the temperature sensor by means of at least one connection, preferably a wire bond or a spring contact.

[0033] Preferably, after connection to the circuit board, a potting compound is poured at least partially onto and / or around the temperature measuring device, preferably into a recess in the casing.

[0034] The invention further relates to the use of the arrangement according to the invention in a high-voltage charging connector or an electric vehicle. SHORT DESCRIPTION OF THE CHARACTERS Fig. 1(a) shows a perspective view of a high-voltage temperature measuring arrangement according to the invention. Fig. 1(b) shows a sectional view of the high-voltage temperature measuring arrangement of Fig. 1(a). Fig. 2 shows a schematic sectional view referring to a section of Fig. 1(b). Fig. 3 shows in perspective view the Fig. 3(a), the frontal view 3(b), the cross-sectional view 3(c) along the line AA, and the enlargement of the area B in Fig. 3(d) a high-voltage temperature measuring arrangement according to the invention in a charging plug. DETAILED DESCRIPTION OF THE INVENTION

[0035] The Fig. Figure 1(a) shows a high-voltage temperature measuring arrangement 1 according to the invention for measuring the temperature of an electrically conductive component 2 of a high-voltage interface during high-voltage operation. The component 2 can connect two contact parts (not shown) and thus establish an interface between these two contact parts. Fig. Figure 1(a) shows the electrically conductive component 2, which is designed as a flat rail. Furthermore, this embodiment has a temperature measuring device 4, which comprises a temperature sensor 4a and a ceramic body 4b, which are shown in the schematic sectional view in Fig. 2 Shown in detail.

[0036] The Fig. 2 shows that the ceramic body 4b has a first surface region 9 and a second surface region 10 formed on opposite sides of the ceramic body 4b. The temperature sensor 4a is arranged on the first surface region 9 to measure the temperature of the first surface region 9. The temperature of the first surface region 9 essentially corresponds to the temperature of the electrical component 2, whose heat is conducted to the temperature sensor 4a via the ceramic body 4b. The second surface region 10 of the temperature sensor 4a is sintered onto at least a portion of the component 2.

[0037] The Fig. 2 shows a layer of sintering paste 8 which is present between the second surface area 10 and the component 2.

[0038] The Fig. 1(a) and Fig. 1(b) shows the circuit board 6, which is connected to the temperature sensor 4a via the electrically conductive connection 7. In particular, two electrically conductive connections 7, for example, wire bonds, are provided. The circuit board 6 is spaced from the component 2 and mechanically connected via a jacket 3.

[0039] The Fig. 1(a) and Fig. 1(b) show the electrically insulating jacket 3, which at least partially surrounds the component 2. The jacket 3 has a recess 11, which is designed as a cavity. Fig. 1(b) shows that the depression 11 extends through the entire depth of the shell 3, so that the shell 3 has no bottom in the depression 11, but is interrupted. Then the shell 3 encloses in the Fig. 1(b) the component 2 from all sides, ie encloses the component 2 completely all the way around.

[0040] The Fig. 1(b) further shows that the temperature measuring device 4 is arranged within the recess 11. The recess 11 is so wide that the temperature measuring device 4 is spaced apart from the casing 3. In particular, the temperature sensor 4a is free from the casing 3. The recess 11 is circular in a plan view, as in Fig. 1(a). The recess 11 is located substantially in the center of the casing 3 to protect the temperature sensor 4a, which is housed in the recess 11, from leakage currents.

[0041] The Fig. 1(b) shows the potting compound 5 filling the recess 11 and covering the temperature measuring device 4. The potting compound 5 thus encloses the temperature measuring device 4, with only the connections 7 protruding from the potting compound 5. The height of the jacket 3 can be higher than the potting compound 5.

[0042] During the production of the high-voltage temperature measuring device according to the invention, the temperature measuring device 4 can first be provided with the temperature sensor 4a and the ceramic body 4b. The second surface region 10 is connected to at least a portion of the electrically conductive component 2 by sintering. Prior to this, the second surface region 10 can be metallized, at least in sections. Metallization is recommended for sintering. Alternatively or additionally, a sintering paste 8 can be applied to the second surface region 10 prior to sintering. After sintering, the jacket 3 can be provided, for example by overmolding the component 2 or by attaching a plastic clip, which was produced, for example, by 3D printing. After the jacket 3 has been arranged, the circuit board 6 can be connected to the temperature sensor 4a by means of the connections 7.Subsequently, potting compound 5 can be introduced and thus the temperature measuring device 4 can be enclosed, in particular, in the recess 11 of the casing 3.

[0043] The Fig. Figure 3(a) shows a perspective view of a charging plug, with a portion thereof omitted for better visibility of the high-voltage temperature measuring arrangement 1 according to the invention. The printed circuit board 6 is arranged towards the front of the charging plug. Two charging pins 12 are provided as electrically conductive components, with the temperature measuring device 4 being arranged in the Fig. 3(a) is shown.

[0044] In the frontal view 3(b) the line AA is shown, along which the cross section for the cross-sectional view 3(c) was taken. Fig. Figure 3(c) shows the sheath 3 around a part of the electrical component 2, which is part of the charging pin 12. In the enlargement of area B of the Fig. 3(c) are in Fig.3(d) shows the electrically conductive component 2, the potting compound 5, the jacket 3, the connection 7 and the temperature measuring device 4. REFERENCE SYMBOL 1 high-voltage temperature measuring arrangement 2 electrically conductive component 3 coats 4 Temperature measuring device 4a Temperature sensor 4b Ceramic body 5 Potting compound 6 circuit board 7 Connection 8 Sintering paste 9 first surface of the ceramic body 10 second surface of the ceramic body 11 Deepening 12 charging pin

Claims

[1] High-voltage temperature measuring arrangement (1) for measuring the temperature of an electrically conductive component (2) during operation under high voltage, the high-voltage measuring device comprising: the electrically conductive component (2), a temperature measuring device (4) with a temperature sensor (4a), an electrically insulating material (3, 5), and a printed circuit board (6), wherein the temperature measuring device (4) is thermally conductively connected to the electrically conductive component (2) by sintering, the printed circuit board (6) is arranged at a distance from the electrically conductive component (2) and is electrically and mechanically connected to the temperature sensor (4a) for transmitting measuring signals, and the electrically insulating material (3, 5) surrounds at least the temperature measuring device (4) at least in sections. [2] Arrangement according to claim 1, wherein the temperature measuring device (4) comprises the temperature sensor (4a) and a ceramic body (4b) with a first (9) and a second (10) surface region, wherein the first surface region (9) is thermally conductively connected to the temperature sensor (4a) for measuring the temperature of the first surface region (9) and the second surface region (10) is arranged on at least a portion of the component (2) for thermally conductive connection to the component (2). [3] Arrangement according to claim 2, wherein the temperature measuring device, in particular the second surface region (10), is metallized for connection to the component (2) and / or sintering paste (8) is present between the temperature measuring device, in particular the second surface region (10), and the component (2). [4] Arrangement according to one of the preceding claims, in which the temperature measuring device (4), in particular the temperature sensor (4a), is connected to the printed circuit board (6) for transmitting signals by means of an electrically conductive connection (7), preferably designed as a wire bond or spring contact. [5] Arrangement according to one of the preceding claims, which further comprises an electrically insulating jacket (3) which at least partially surrounds the electrically conductive component (2) and / or at least partially surrounds the temperature measuring device (4) at a distance, wherein optionally the temperature measuring device (4) is at least partially, preferably completely, free from the jacket (3), and in particular the temperature sensor (4a) is free from the jacket (3). [6] Arrangement according to claim 5, wherein the casing (3) has at least one recess (11) in which the temperature measuring device (4) is arranged at least in sections. [7] Arrangement according to one of the preceding claims, in which the electrically insulating material (5), in particular a potting compound, completely covers the temperature measuring device (4) and / or directly surrounds the electrically conductive component (2). [8] Arrangement according to one of the preceding claims 6 and 7, in which the electrically insulating material (5) fills the recess (11) at least in sections. [9] High-voltage charging connector, in particular charging plug, with at least one charging contact for connecting to an electrical contact of a charging connection of an electric vehicle for charging the electric vehicle with high voltage, wherein the charging contact corresponds to the electrically conductive component or is electrically conductively connected to the electrically conductive component, and the charging connector has at least one arrangement according to one of the preceding claims. [10] Electric vehicle with at least one high-voltage interface which connects a first electrically conductive contact part, in particular a charging connection, to a second electrically conductive contact part, in particular an electrical contact of a high-voltage charging connector for charging the electric vehicle, wherein the first or second contact part electrically connects an electrically conductive component to the other contact part, and the high-voltage interface has at least one high-voltage temperature measuring arrangement according to one of the preceding claims. [11] Method for providing a high-voltage temperature measuring device (4) on an electrically conductive component (2) and preferably for producing a high-voltage temperature measuring arrangement (1) according to one of the preceding claims, comprising the following steps: Providing the electrically conductive component (2), a temperature measuring device (4) with a temperature sensor (4a), an electrically insulating material (3, 5), and a printed circuit board (6), and Connecting the temperature measuring device (4) and the component (2) by bonding the temperature measuring device (4) to at least one section of the electrically conductive component (2) by sintering, so that the temperature measuring device (4) is thermally conductively connected to the electrically conductive component (2), wherein in the high-voltage temperature measuring device (4), the printed circuit board (6) is arranged at a distance from the electrically conductive component (2) and is electrically and mechanically connected to the temperature sensor (4a) for transmitting measuring signals, and the electrically insulating material (5) surrounds at least the temperature measuring device (4) at least in sections. [12] Method according to claim 11, wherein the temperature measuring device (4) comprises the temperature sensor (4a) and a ceramic body (4b) with a first (9) and a second (10) surface area, wherein the first surface region (9) is thermally conductively connected to the temperature sensor (4a) for measuring the temperature of the first surface region (9) and the second surface region (10) is arranged on at least a portion of the component (2) for thermally conductive connection to the component (2), wherein the temperature measuring device (4), in particular the second surface region (10), is metallized at least in sections before sintering and / or a sintering paste (8) is applied to the temperature measuring device, in particular the second surface region (10), and / or after sintering, an electrically insulating material, in particular a casting compound (5) and / or a jacket (3), which surrounds the conductive component (2) at least in sections and / or surrounds the temperature measuring device (4) at a distance from it at least in sections, is applied, and / or after sintering, preferably after arranging the electrically insulating material (3, 5), a printed circuit board (6) is electrically conductively connected to the temperature sensor (4a) by means of at least one connection (7), preferably a wire bond or a spring contact, and / or after connection to the circuit board (6), a potting compound (5) is poured at least in sections onto and / or around the temperature measuring device (4), preferably into a recess (11) in the casing (3).

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