HIGH VOLTAGE CONTACT SYSTEM

Abstract

High-voltage contact system (100), with: two high-voltage contacts (101, 102) designed to form a high-voltage connection in a battery-powered vehicle; a temperature sensor (103) arranged between the two high-voltage contacts (101, 102) and configured to detect a temperature based on the temperatures of both of the two high-voltage contacts (101, 102); and a thermally conductive, electrically insulating element (104) which embeds the temperature sensor (103) and contacts the two high-voltage contacts (101, 102), wherein the thermally conductive, electrically insulating element (104) forms a thermal bridge between the two high-voltage contacts (101, 102) and the temperature sensor (103), so that the temperature sensor (103) can detect the temperature based on the temperatures of both of the high-voltage contacts (101, 102), characterized in that that the thermally conductive, electrically insulating element (104) is an elastomer and the contact between the thermally conductive, electrically insulating element (104) and the two high-voltage contacts (101, 102) is formed by overpressing the elastomer over the two high-voltage contacts (101, 102) or by pressing the two high-voltage contacts (101, 102) into the elastomer, wherein the overpressing or pressing in forms an air gap-free thermal bridge between the thermally conductive, electrically insulating element (104) and the two high-voltage contacts (101, 102).

Description

Technical field

[0001] The present invention relates to a high-voltage (HV) contact system with two high-voltage contacts for forming a high-voltage connection, for example with a drive unit or with a high-voltage battery of a battery-powered vehicle. The invention relates in particular to techniques for temperature measurement with a temperature sensor for both DC contacts of a high-voltage contact system. State of the art

[0002] Measuring temperatures in high-voltage connector systems and high-voltage contact systems in the automotive industry helps prevent thermal overload of the connector system and its associated wiring. Furthermore, it allows for the detection of potential mechanical damage and / or aging effects that could lead to elevated or even critical temperatures within the connector system, enabling timely measures to prevent further damage. Current standard solutions measure the contact poles (+ or -) using a single temperature sensor each. Using two temperature sensors would require more installation space, increase the complexity of the connector system, and consequently, result in higher manufacturing costs.

[0003] Monitoring the temperature of two contacts with a common temperature sensor is known, for example, from CN 1 13 594 799 A, which forms the basis of claim 1. CN 2 17 562 844 U discloses a power connector for electrical connection to the charging port, and US 2016 / 0 104 978 A1 discloses an electrical accessory. JP 2002-352 635 A describes a power cable for supplying power to an electrical device. JP H04-2 480 U discloses a system for correcting axis misalignment. DE 10 2020 116 533 A1 discloses a high-current contacting device. DE 10 2018 133 100 A1 reveals a temperature sensing unit and DE 10 2019 114 229 A1 reveals a charging plug. Description of the invention

[0004] One object of the invention is therefore to create an improved contact system for the electrical contacting of the contact poles of the high-voltage battery, in which the temperature of the contact poles can be monitored in a space-efficient and cost-effective manner.

[0005] The problem is solved by the subject matter of independent claim 1. Advantageous embodiments of the invention are specified in the dependent claims, the description, and the accompanying figures.

[0006] The inventive solution is based on the idea of ​​using a temperature sensor that is thermally coupled to both DC contacts (positive and negative) via a thermally conductive and insulating elastomer. The temperature sensor can be positioned centrally between the two DC contacts (DC+ and DC-) and encased (e.g., overmolded or embedded) in a thermally conductive, insulating elastomer that contacts both DC contacts. This silicone adheres, for example, to a rigid component to ensure creepage resistance, optionally through a two-component injection molding process. The compression between the elastomer and the high-voltage contacts allows for efficient thermal heat transfer, eliminating the need for additional heat-conducting elements such as gap fillers (i.e., materials for filling air gaps).This means that the complexity and cost of the sensor system can be reduced to a minimum, while still achieving sufficiently good temperature measurement.

[0007] This inventive solution enables cost-effective temperature measurement while simultaneously reducing installation space. The complexity of the connector system can thus be reduced (or simplified). Both high-voltage contacts can be measured with just one sensor. Thermal overload in the connector system or cable harness ("derating") can be detected early. Furthermore, mechanical damage, such as that caused by aging, which results in increased thermal stress, can be detected.

[0008] According to a first aspect, the problem described above is solved by a high-voltage contact system comprising: two high-voltage contacts configured to form a high-voltage connection in a battery-powered vehicle; a temperature sensor arranged between the two high-voltage contacts and configured to detect a temperature based on the temperatures of both of the two high-voltage contacts; and a thermally conductive, electrically insulating element embedding the temperature sensor and contacting the two high-voltage contacts, wherein the thermally conductive, electrically insulating element forms a thermal bridge between the two HV contacts and the temperature sensor, so that the temperature sensor can detect the temperature based on the temperatures of both of the high-voltage contacts.

[0009] The two high-voltage contacts can, for example, form a high-voltage connection with a traction unit or a drive unit of the battery-powered vehicle, or they can form a high-voltage connection with a high-voltage battery of the battery-powered vehicle, or with a charging socket, or with HV auxiliary consumers of the battery-powered vehicle.

[0010] With such a high-voltage contact system, the temperature of the contact poles can be monitored in a space-saving and cost-effective manner. It has been shown that using a single temperature sensor eliminates the need for a second sensor, thus reducing installation space and costs. This single temperature sensor can monitor the temperatures of both high-voltage contacts simultaneously. By thermally connecting the sensor to the two HV contacts via a thermally conductive, electrically insulating element, the current temperatures of both HV contacts can be measured simultaneously. The temperature sensor does not measure the two temperatures separately, but rather as a single temperature reading that provides information about the thermal state of both HV contacts.

[0011] According to an exemplary embodiment of the high-voltage contact system, the temperature sensor is arranged centrally between the two high-voltage contacts, so that it can detect a temperature that lies between the temperature of one of the two high-voltage contacts and the temperature of one of the two high-voltage contacts.

[0012] The temperature detected by the temperature sensor could, for example, be a temperature that lies between the temperature of the first HV contact and the temperature of the second HV contact. It could be, for instance, an average of the two temperatures or a weighted average where a higher temperature is weighted more heavily than a lower temperature.

[0013] According to the invention, the thermally conductive, electrically insulating element is an elastomer, and the contact between the thermally conductive, electrically insulating element and the two high-voltage contacts is formed by overpressing the elastomer over the two high-voltage contacts or by pressing the two high-voltage contacts into the elastomer.

[0014] With such an elastomer, good heat transfer from the HV contacts to the elastomer can be achieved, since the elastomer is in direct contact with the HV contacts due to the over-pressing or pressing-in process.

[0015] According to the invention, the overpressing or pressing in forms an air gap-free thermal bridge between the thermally conductive, electrically insulating element and the two high-voltage contacts.

[0016] Such overpressure or pressing in allows for good thermal conductivity because no air gaps occur. Therefore, no gap filler material is required.

[0017] According to an exemplary embodiment of the high-voltage contact system, the temperature sensor is embedded in the elastomer or overmolded by the elastomer.

[0018] This achieves the technical advantage that the temperature sensor is directly adjacent to the elastomer, so that the heat is transferred via the contact surface between the elastomer and the temperature sensor, and no thermally insulating material such as air is in between.

[0019] According to an exemplary embodiment of the high-voltage contact system, the high-voltage contact system comprises: a second electrically insulating element arranged between the two high-voltage contacts and configured to electrically isolate the two high-voltage contacts from each other; wherein the thermally conductive, electrically insulating element is formed as a soft component and the second electrically insulating element is formed as a hard component.

[0020] The hard component provides the necessary mechanical stability, while the soft component ensures good heat transfer from the HV contacts to the temperature sensor.

[0021] According to an exemplary embodiment of the high-voltage contact system, the thermally conductive, electrically insulating element is formed as a 2K injection-molded soft component and the second electrically insulating element is formed as a 2K injection-molded hard component.

[0022] This allows the contact system to be efficiently manufactured using 2-component injection molding, in which the temperature sensor is embedded in or overmolded by the soft component.

[0023] According to an exemplary embodiment of the high-voltage contact system, each of the two high-voltage contacts has a notch, and the thermally conductive, electrically insulating element has two grooves which are pressed into the corresponding notches of the high-voltage contacts, each forming air-gap-free connections with the high-voltage contacts.

[0024] The notches ensure good mechanical stability for attaching the electrically insulating element to the HV contacts. Furthermore, the air-gap-free connections to the HV contacts result in good heat transfer.

[0025] According to an exemplary embodiment of the high-voltage contact system, the thermally conductive, electrically insulating element has a third groove that is arranged between the two high-voltage contacts and is attached to the second insulating element, the third groove forming an air-gap-free connection with the two high-voltage contacts.

[0026] The third groove allows the thermally conductive, electrically insulating element to be securely fastened to the second insulating element, for example, via a notch in the second insulating element. The temperature sensor can be located within the thermally conductive, electrically insulating element, either near or inside the third groove, thus minimizing the distance to the two high-voltage contacts and optimizing heat transfer between the two high-voltage contacts and the temperature sensor.

[0027] This disclosure describes high-voltage (HV) contacts and HV batteries. For high-voltage vehicles to be powered at a level acceptable to the vehicle owner, the electric motors must operate at very high currents and voltages. Systems and components operating in motor vehicles above 25 V AC or 60 V DC are referred to as high-voltage (HV) systems or HV vehicles. Voltages exceeding 25 V AC or 60 V DC can have dangerous effects on the human body. In current HV vehicles, the voltages of the HV system range between 100 V and 800 V DC. The high-voltage systems of most current electric cars operate at a voltage level of around 400 volts.

[0028] This disclosure describes hard and soft components as they are commonly produced in injection molding, particularly two-component (2K) injection molding. In 2K injection molding, the first component is often the robust, shape-defining component. Therefore, it is also referred to as the hard component. Materials used include, for example, PP (polypropylene), PS (polystyrene), PC (polycarbonate) + acrylonitrile butadiene styrene copolymer (ABS), polyamide (PA), or polybutylene terephthalate (PBT). The second component is often soft and elastic. Therefore, it is also referred to as the soft component. Seals are frequently injected directly onto a substrate as a soft component in 2K injection molding. Materials used include, for example, thermoplastic elastomer (TPE), ethylene propylene diene monomer (EPDM) rubber, or liquid silicone rubber (LSR).

[0029] This disclosure describes press-fit and press-fit techniques. In this disclosure, a press-fit technique is defined as a joining technique in which an elastic element or elastomer is pressed or forced over a solid second element, such as HV contacts, to create a tight connection between the two elements. An opening, indentation, or hole in the elastic element is pressed over a corresponding protrusion, such as a groove or pin, in the second element, resulting in a tight, thermally conductive connection between the two elements. The diagonal of the pin cross-section of the second solid element is larger than the diameter of the hole in the elastic element. Pressing the pin edges into the hole of the elastic element creates a thermally conductive connection characterized by high reliability and durability.The overpressure that occurs during pressing can be absorbed either by the deformation in the hole or the deformation of the pin. Brief character description

[0030] The invention will now be described in more detail with reference to exemplary embodiments and the figures. The figures show: Fig. 1 a schematic representation of a contact system 100 according to the invention with a temperature sensor for measuring the temperature of the two HV contacts; Fig. 2 a 2D sectional view of the contact system 100 according to the invention to illustrate the temperature measurement concept; and Fig. 3 a 2D section of the contact system 100 according to the invention to illustrate the temperature measurement connection.

[0031] The figures are merely schematic representations and serve only to illustrate the invention. Identical or equivalent elements are consistently identified by the same reference numerals.

[0032] The following detailed description refers to the accompanying drawings, which form part thereof and illustrate specific embodiments in which the invention can be implemented. It is understood that other embodiments can also be used and structural or logical modifications can be made without deviating from the concept of the present invention. Therefore, the following detailed description is not to be understood as limiting. Furthermore, it is understood that the features of the various embodiments described herein can be combined with one another, unless specifically stated otherwise.

[0033] The aspects and embodiments are described with reference to the drawings, where the same reference numerals generally refer to the same elements. For explanatory purposes, numerous specific details are presented in the following description to provide a thorough understanding of one or more aspects of the invention. However, it may be obvious to a person skilled in the art that one or more aspects or embodiments can be implemented with a lesser degree of specific detail. In other cases, known structures and elements are shown schematically to facilitate the description of one or more aspects or embodiments. It is understood that other embodiments may be used and structural or logical modifications may be made without departing from the concept of the present invention.

[0034] Fig. Figure 1 shows a schematic representation of a contact system 100 according to the invention with a temperature sensor for measuring the temperature of the two HV contacts.

[0035] The high-voltage contact system 100 comprises two high-voltage contacts 101, 102, a temperature sensor 103; and a thermally conductive, electrically insulating element.

[0036] The two high-voltage contacts 101, 102 are designed to form a high-voltage connection in a battery-powered vehicle.

[0037] The two high-voltage contacts can, in particular, form a high-voltage connection with a traction unit or drive unit of the battery-powered vehicle. Furthermore, they can form a high-voltage connection with a high-voltage battery of the battery-powered vehicle, with a charging socket, or with high-voltage auxiliary consumers of the battery-powered vehicle.

[0038] The temperature sensor 103 is arranged between the two high-voltage contacts 101, 102 and is designed to detect a temperature based on the temperatures of both of the two high-voltage contacts 101, 102.

[0039] The thermally conductive, electrically insulating element 104 embeds the temperature sensor 103 and contacts the two high-voltage contacts 101, 102. The thermally conductive, electrically insulating element 104 forms a thermal bridge between the two HV contacts 101, 102 and the temperature sensor 103, so that the temperature sensor 103 can detect the temperature based on the temperatures of both of the high-voltage contacts 101, 102.

[0040] For example, the temperature sensor 103 can detect a temperature as a thermal average of the temperatures of the two HV contacts 101, 102.

[0041] The thermally conductive, electrically insulating element 104 is an electrically insulating elastomer, such as silicone, which is enriched with additives to improve its thermal conductivity. These additives, for example as micrometer particles embedded in silicone, improve heat transfer within the thermally conductive, electrically insulating element 104.

[0042] The two high-voltage contacts can connect the HV battery to an electric motor of the battery-powered vehicle to drive the vehicle, or to a charging infrastructure to recharge the HV battery.

[0043] The temperature sensor 103, for example, consists of a sensor capsule 103c and two connecting wires 103a, 103b, as shown in Fig. 2 shown in more detail.

[0044] The temperature sensor 103 can be designed, for example, as an NTC, PTC, or platinum sensor, in which the resistance value of the material of the sensor capsule 103c changes with temperature. This temperature change can be displayed via the two connecting wires and, for example, transmitted to a control unit.

[0045] In one embodiment, the sensor capsule is overmolded with silicone (soft component), which constitutes the thermally conductive, electrically insulating element 104 and is thus held in position. The silicone makes contact with both poles or HV contacts 101, 102 through the resulting overpressure. Heat transfer occurs from both contacts 101, 102 via the thermally conductive silicone 104 to the temperature sensor 103.

[0046] Fig. Figure 2 shows a 2D sectional view of the contact system 100 according to the invention to illustrate the temperature measurement concept.

[0047] As above Fig. As already shown schematically in Figure 1, the high-voltage contact system 100 comprises: two high-voltage contacts 101, 102 configured to form a high-voltage connection in a battery-powered vehicle; a temperature sensor 103 arranged between the two high-voltage contacts 101, 102, configured to detect a temperature based on the temperatures of both of the two high-voltage contacts 101, 102; and a thermally conductive, electrically insulating element 104 which embeds the temperature sensor 103 and contacts the two high-voltage contacts 101, 102.

[0048] The thermally conductive, electrically insulating element 104 forms a thermal bridge between the two HV contacts 101, 102 and the temperature sensor 103, so that the temperature sensor 103 can detect the temperature based on the temperatures of both of the high-voltage contacts 101, 102.

[0049] As shown in the illustration in Fig. As can be seen in Figure 2, the temperature sensor 103 is arranged centrally between the two high-voltage contacts 101, 102, so that it can detect a temperature that lies between the temperature of a first 101 of the two high-voltage contacts 101, 102 and the temperature of a second 102 of the two high-voltage contacts 101, 102, for example an average value or a weighted average value of the two temperatures of the HV contacts 101, 102.

[0050] As described above, the thermally conductive, electrically insulating element 104 is an elastomer, in particular a silicone. The contact between the thermally conductive, electrically insulating element 104 and the two high-voltage contacts 101, 102 is formed by either pressing the elastomer over the two high-voltage contacts 101, 102 or pressing the two high-voltage contacts 101, 102 into the elastomer.

[0051] In this process, such over-pressing or pressing in forms an air-gap-free thermal bridge between the thermally conductive, electrically insulating element 104 and the two high-voltage contacts 101, 102.

[0052] The temperature sensor 103 can, for example, be embedded in the elastomer 104 or be overmolded by the elastomer 104.

[0053] As further in Fig. As shown in Figure 2, the high-voltage contact system 100 can comprise a second electrically insulating element 105, which is arranged between the two high-voltage contacts 101, 102 and is configured to electrically isolate the two high-voltage contacts 101, 102 from each other. Preferably, the thermally conductive, electrically insulating element 104 can be configured as a soft component and the second electrically insulating element 105 can be configured as a hard component.

[0054] For example, the thermally conductive, electrically insulating element 104 can be formed as a 2K injection molded soft component and the second electrically insulating element 105 can be formed as a 2K injection molded hard component.

[0055] Fig. Figure 3 shows a 2D section of the contact system 100 according to the invention to illustrate the temperature measurement connection.

[0056] The 2D section is a closer representation of the thermally conductive, electrically insulating element 104 and its contact surfaces to the two HV contacts 101, 102 as well as its contact surface to the temperature sensor 103.

[0057] As in Fig. As can be seen in Figure 3, each of the two high-voltage contacts 101, 102 can have a notch 101a, 102a. The thermally conductive, electrically insulating element 104 can have two grooves 104a, 104b, which are pressed into the corresponding notches 101a, 102a of the high-voltage contacts 101, 102, and each form air-gap-free connections with the high-voltage contacts 101, 102. The air-gap-free connections ensure particularly good heat transfer across these contact surfaces.

[0058] In the presentation of the Fig.3. The thermally conductive, electrically insulating element 104 can have a third groove 104c, which is arranged between the two high-voltage contacts 101, 102 and attached to the second insulating element 105, for example as a 2K injection molded connection. The third groove 104c can form an air-gap-free connection with the two high-voltage contacts 101, 102. This air-gap-free connection ensures particularly good heat transfer via the contact surfaces between the HV contacts 101, 102 and the third groove 104c of the electrically insulating element 104. REFERENCE MARK LIST 100 high-voltage contact system 101 First high-voltage contact 102 second high-voltage contact 103 Temperature sensor 103a / b Connection wires of the temperature sensor 103c Sensor head of the temperature sensor 104 thermally conductive, electrically insulating element 105 second electrically insulating element 104a first groove of the thermally conductive, electrically insulating element 104b second groove of the thermally conductive, electrically insulating element 104c third groove of the thermally conductive, electrically insulating element 101a Notch of the first high-voltage contact 102a Notch of the second high-voltage contact

Claims

[1] High-voltage contact system (100), with: two high-voltage contacts (101, 102) designed to form a high-voltage connection in a battery-powered vehicle; a temperature sensor (103) arranged between the two high-voltage contacts (101, 102) and configured to detect a temperature based on the temperatures of both of the two high-voltage contacts (101, 102); and a thermally conductive, electrically insulating element (104) which embeds the temperature sensor (103) and contacts the two high-voltage contacts (101, 102), wherein the thermally conductive, electrically insulating element (104) forms a thermal bridge between the two high-voltage contacts (101, 102) and the temperature sensor (103), so that the temperature sensor (103) can detect the temperature based on the temperatures of both of the high-voltage contacts (101, 102), characterized by , that the thermally conductive, electrically insulating element (104) is an elastomer and the contact between the thermally conductive, electrically insulating element (104) and the two high-voltage contacts (101, 102) is formed by overpressing the elastomer over the two high-voltage contacts (101, 102) or by pressing the two high-voltage contacts (101, 102) into the elastomer, wherein the overpressing or pressing in forms an air gap-free thermal bridge between the thermally conductive, electrically insulating element (104) and the two high-voltage contacts (101, 102). [2] High-voltage contact system (100) according to claim 1, wherein the temperature sensor (103) is arranged centrally between the two high-voltage contacts (101, 102) so that it can detect a temperature which lies between the temperature of a first (101) of the two high-voltage contacts (101, 102) and the temperature of a second (102) of the two high-voltage contacts (101, 102). [3] High-voltage contact system (100) according to claim 1 or 2, wherein the temperature sensor (103) is embedded in the elastomer (104) or is overmolded by the elastomer (104). [4] High-voltage contact system (100) according to one of the preceding claims, comprising: a second electrically insulating element (105) which is arranged between the two high-voltage contacts (101, 102) and is designed to electrically insulate the two high-voltage contacts (101, 102) from each other; wherein the thermally conductive, electrically insulating element (104) is formed as a soft component and the second electrically insulating element (105) is formed as a hard component. [5] High-voltage contact system (100) according to claim 4, wherein the thermally conductive, electrically insulating element (104) is formed as a 2K injection molded soft component and the second electrically insulating element (105) is formed as a 2K injection molded hard component. [6] High-voltage contact system (100) according to claim 4 or 5, wherein each of the two high-voltage contacts (101, 102) has a notch (101a, 102a) and wherein the thermally conductive, electrically insulating element (104) has two grooves (104a, 104b) which are pressed into the corresponding indentations (101a, 102a) of the high-voltage contacts (101, 102) and each form air-gap-free connections with the high-voltage contacts (101, 102). [7] High-voltage contact system (100) according to claim 6, wherein the thermally conductive, electrically insulating element (104) has a third groove (104c) which is arranged between the two high-voltage contacts (101, 102) and is attached to the second insulating element (105), wherein the third groove (104c) forms an air gap-free connection with the two high-voltage contacts (101, 102).

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