Shield transfer for a plug connection

Abstract

Contact arrangement (300) for the transfer of a shielding layer (304) surrounding a first component, in particular an electrical line (221), to a shielding of another component (200, 203); wherein - the contact arrangement (300) comprises a plurality of contact elements (302), each of which is designed to electrically conductively contact the shielding of the other component; - the contact elements (302) are distributed over a circumference of the shielding layer (304); and - a first subset of the contact elements (302) is designed to enable a contact resistance to the shielding of the other component (200, 203) which is 10%, 20%, 50% or more lower than a contact resistance enabled by a contact element (302) of a complementary second subset of the contact elements (302).

Description

The invention relates to a plug connection for transmitting electrical energy. In particular, the invention relates to an efficient screen transfer for such a plug connection.An electric drive vehicle (e.g. a PHEV, plug-in hybrid electric vehicle, or a BEV, a battery electric vehicle) comprises at least one electrical energy store (e.g. a battery) which can be connected to a charging station and charged via a charging device of the vehicle. The electrical energy from the electrical energy store can be conducted via electrical lines to an electric drive motor of the vehicle in order to operate the drive motor and to drive the vehicle. The electrical lines for transmitting electrical drive energy can be referred to as power lines. Typically, a direct current is transmitted from the electrical energy store to the drive motor (in particular to an inverter of the drive motor) via a pair of power lines. The voltage between a pair of power lines is typically in the range of 300V or more. The power lines can therefore also be referred to as high-voltage (HV) lines.A line for transmitting electrical energy typically has a shielding surrounding the line, in particular an EMC (electromagnetic compatibility) shielding. At a contact point of the line with another component (e.g. at a plug connection), a screen transfer typically takes place from the screen layer of the line to the screen of the other component in order to ensure continuous EMC shielding.The present document is concerned with the technical object of providing a cost-effective and reliable screen transfer for a (DC) power line, in particular for an at least partially electrically driven vehicle.The object is achieved by the independent claim. Advantageous embodiments are described inter alia in the dependent claims. It is pointed out that additional features of a claim dependent on an independent claim can form a separate invention which is independent of the combination of all features of the independent claim without the features of the independent claim or only in combination with a subset of the features of the independent claim and which can be made the subject matter of an independent claim, a divisional application or a subsequent application. This applies in the same way to technical teachings described in the description, which may form an invention independent of the features of the independent claims.According to one aspect, a contact arrangement for transferring a shielding layer of a first component (in particular an electrical line) to a shielding of another component is described. The screen layer surrounds (completely) the first component (in particular the electrical line). The shielding layer is typically electrically conductive and is configured to electrically and / or magnetically shield the first component (in particular the electrical line). The other component can be, for example, an electrical load (for example, an inverter and / or an electric machine) or an electrical energy store of a vehicle. Electrical energy (in particular a direct current) for operating the other component can be transmitted via the electrical line. In this case, the electrical line can be designed to transmit electrical powers of 5 kW, 10 kW, 50 kW or more. The current flowing through the line may include a DC portion and an AC portion. The DC component can be greater than the AC component by a factor of 10 or more. The alternating current component can be effected, for example, by switching elements of an inverter. The AC component may comprise frequencies of 100 kHz, 1 MHz or more.A contact arrangement for an electrical line is described below in order to enable screen transfer to the screen of another component. It is pointed out that the contact arrangement can be used in a corresponding manner for the screen transfer from a screen of another component (in particular an energy store and / or an electrical load) to the screen layer of an electrical line.The contact arrangement comprises a plurality of contact elements which are each designed to make electrically conductive contact with the shielding of the other component. In this case, the contact elements are distributed, in particular uniformly, over a circumference of the shielding layer. For example, the contact arrangement may comprise 10, 20 or more contact elements which are arranged (uniformly) distributed over the periphery of the shielding layer, i.e. over a cross section of the shielding layer. By providing a plurality of contact elements arranged in a distributed manner, a low transfer impedance of the shielding layer to the shielding can be ensured even at relatively high frequencies of the alternating current component of the current flowing in the line. Reliable electrical and / or magnetic shielding is thus made possible even for relatively high frequencies.The contact arrangement can be part of a plug component (e.g. a plug or a socket) for a plug connection, which connects the electrical line to the other component in an electrically conductive manner. The contact arrangement can be designed to be "pluggable" in this case. In particular, the contact arrangement can be designed in such a way that the contact elements each contact the shield of the other component (for example, complementary contact elements of a complementary plug-in component of the other component) when the plug-in component is plugged together with the complementary plug-in component.For example, an empty region can be arranged between two directly adjacent contact elements. The contact arrangement can thus be formed from a sequence of contact elements and intermediate void regions which extends around the circumference of the line. A contact arrangement having N contact elements (e.g. N=10, 20 or more) can have N empty regions. A blank region can be configured to receive a complementary contact element of the shielding or of the contact arrangement of the other component, so that an electrically conductive connection is produced between the contact element of the shielding of the other component and the two directly adjacent contact elements. A contact element of the contact arrangement can thus be designed to establish an electrically conductive connection to exactly one or two complementary contact elements of the shielding of the other component (e.g. within the scope of a plug connection). Thus, a reliable screen transfer for providing a high-quality screen for high-frequency current components can be ensured.The contact elements of a contact arrangement can be divided into a first subset and into a complementary second subset, such that the first subset and the second subset together result in the totality of the contact elements of the contact arrangement. The first subset preferably comprises exactly one contact element and the second subset comprises the remaining contact elements of the contact arrangement. A particularly cost-effective contact arrangement for screen transfer can thus be provided.The first subset of the contact elements can be configured to enable in each case a transition resistance to the shielding of the other component which is lower, in particular lower by 10%, 20%, 50% or more, than a transition resistance enabled in each case by a contact element of the complementary second subset of the contact elements. In particular, any contact element of the first subset can enable a lower contact resistance for screen transfer than any contact element of the second subset.The provision of at least one contact element with a relatively low contact resistance ensures a low DC resistance of the screen transfer for the DC component of a current flowing through the line. However, the provision of a particularly low transition resistance is typically associated with special measures which lead to additional costs. Due to the fact that these particular measures are implemented only for a first subset of the contact elements (and not for the entirety of the contact elements), a cost-effective screen transfer can be enabled. Overall, a cost-effective and reliable screen transfer for an electrical line is thus made possible, through which both a direct current and an alternating current flow.A low contact or transition resistance can be effected by one or more different measures. In this case, the contact or transition resistance can comprise an impurity layer portion which is effected by an impurity layer (in particular an oxide layer) formed on the surface of a contact element. Alternatively or additionally, the contact or contact resistance can comprise a narrow resistance component which is caused by a roughness or by an unevenness of the surface of a contact element.A contact element of the first subset may have a lower susceptibility to the formation of a foreign layer (in particular a lower oxidation capability) than a contact element of the second subset. In a corresponding manner, the complementary contact element of the shielding, which forms an electrically conductive connection with a contact element of the first subset, can also have a reduced susceptibility to the formation of a foreign layer.At least the surface of a contact element of the first subset can comprise a noble metal, in particular gold and / or silver, or consist of a noble metal. On the other hand, a contact element and / or the surface of a contact element of the second subset cannot comprise any noble metal, in particular no gold and / or silver. The use of noble metals can thus be restricted to the one or more contact elements of the first subset. Thus, the costs for a contact arrangement for screen transfer can be reduced to a particular extent.Alternatively or additionally, a contact element of the first subset can have a lower roughness, in particular a lower average roughness, than a contact element of the second subset. In a corresponding manner, the complementary contact element of the shielding, which forms an electrically conductive connection with a contact element of the first subset, can also have a reduced roughness. A reduced roughness can be effected, for example, by surface processing (for example by grinding) of the surface of a contact element of the first subset. Thus, the density resistance portion of the contact resistance can be reduced.Alternatively or additionally, a contact element of the first subset can have a larger surface, in particular a surface which is larger by 10%, 20%, 50% or more, for contacting the shielding of the other component than a contact element of the second subset. The use of contact elements of different sizes also makes it possible to bring about a locally reduced contact resistance or transition resistance of at least one contact element.According to a further aspect, a plug-in component for a plug-in connection of an electrical line to another component (e.g. an electrical load or an energy store of a vehicle) is described. The electrical line is surrounded by a shielding layer. Furthermore, the other component has a shielding. The plug component can be designed as a plug or as a socket. The male component may be connected to the electrical lead to form a male connection with a complementary male component of the other component. On the other hand, the plug component can be connected to the other component in order to form a plug connection with a complementary plug component of the electrical line.The male component may include a housing. Furthermore, the plug-in component can comprise at least one contact part (e.g. a pin) for contacting the electrical line with the other component. Furthermore, the plug-in component comprises a contact arrangement described in this document for contacting the shielding layer with the shielding of the other component. The contact elements of the contact arrangement can be designed in such a way that the contact elements can be plugged together with contact elements of the complementary plug-in component of the plug-in connection that are arranged in a complementary manner.According to a further aspect, a vehicle, in particular a road motor vehicle, for example a passenger car or a truck or a bus, is described, which comprises the plug-in component described in this document. In particular, the vehicle can comprise an electrical line for transmitting electrical energy to an electrical load of the vehicle. In addition, the vehicle can comprise a plug-in component described in this document for electrically contacting the electrical line with the electrical load.It should be noted that the methods, devices, and systems described herein may be used both alone and in combination with other methods, devices, and systems described herein. Furthermore, any aspects of the methods, apparatus, and systems described herein may be combined in a variety of ways. In particular, the features of the claims can be combined with one another in many ways.The invention is described in more detail below with reference to exemplary embodiments. Figure shows FIG. 1 is a block diagram of an example charging system for an energy storage of a vehicle; FIG. 2 ashows an exemplary inverter for a drive machine of a vehicle; FIG. 2 b shows an example wiring inside a vehicle; and FIGS. 3 aand 3 b show exemplary screen transfer contact arrangements.As stated at the beginning, the present document is concerned with the reliable and efficient transfer of the shielding of a line to the shielding of another component (or in the opposite direction), in particular within the scope of a plug connection.FIG. 1 shows a block diagram of an exemplary charging system 100 having a charging station 110 and a vehicle 120 in this context. The vehicle 120 comprises an electrical energy store 122, which can be charged with electrical energy from the charging station 110. The vehicle 120 comprises a charging interface, in particular a charging socket 121, to which a corresponding plug 111 of a charging cable 112 can be plugged. The charging socket 121 and the plug 111 form a plug-in system.The vehicle 120 comprises a control unit 123 which is configured to control a charging process at the charging station 110. For this purpose, the control unit 123 of the vehicle 120 may be configured to communicate with the charging station 110 according to a predefined communication protocol.FIG. 2 ashows an exemplary inverter (or inverter) 200 which is configured to generate phase voltages 211 (i.e. AC voltages) for the coils of an electric drive machine 203 of the vehicle 120 on the basis of an on-board power supply voltage VB 210 (i.e. a DC voltage). The vehicle electrical system voltage 210 can be provided by the energy store 122 of the vehicle 120 via electrical power lines 221. The inverter 200 (or inverter) comprises a plurality of switches 202, which in the example shown are each arranged in a half bridge for each phase. The switches 202 are controlled by a control unit 201 in order to generate the phase voltages 211 for the electric machine 203. The control signals may be transmitted to the switches 202 via control lines 222.FIG. 2 b shows an example wiring in a vehicle 120. In particular, FIG. 2 b shows one or more signal lines 222 which connect the control unit 201 to an electrical load 200, 203 (e.g. the inverter 200 and / or the electric drive machine 203) by means of a signal plug connection 232 in order to transmit control signals to the electrical load 200, 203. Furthermore, FIG. 2 bshows one or more power lines 221 which connect the electrical load 200, 203 to the electrical energy store 122 via a power plug connection 231 in order to transmit electrical supply energy to the electrical load 200, 203.The lines 221, 222, in particular the power lines 221, typically have shielding. In this case, a shielding or a shielding layer usually completely encloses a line 221 in order to ensure reliable electrical and / or magnetic shielding. FIG. 3 bshows the cross section of an exemplary line 221 and a shielding layer 304 enclosing the line 221.At a contact point to another component 200, 203, in particular at a plug connection 231, the shielding layer 304 typically also has to be reliably transferred to shielding of the other component 200, 203 in order to ensure continuous electrical and / or magnetic shielding. For this purpose, the shielding layer 304 may comprise a plurality of contact elements 302 at the contact point, wherein the individual contact elements 302 may each form an electrically conductive connection to at least one corresponding contact element of the other component. The contact elements 302 can be distributed (optionally uniformly) over the circumference of the line 221 or of the shielding layer 304, in order to enable the lowest possible contact resistance over the entire circumference of the shielding layer 304.A line 221 can thus have a circumferential shielding 304, wherein the shielding 304 can have a plurality of contact elements 302 for the shielding transfer at a contact point. The contact elements 302 may comprise noble materials such as gold or silver. For example, the contact elements 302 can have a base structure made of a copper alloy coated with a noble metal. As a result, a low DC resistance and a low transfer impedance can be ensured. The contact elements 302 may be distributed over the perimeter of the shielding layer 304, as shown in FIG. 3 b.The provision of a plurality of contact elements 302 each comprising noble metals is associated with relatively high costs. Experiments have shown that it is sufficient (in particular to provide a low transfer impedance) to use a circumferential screen contact made of a relatively base material (e.g. a copper or tin alloy). Thus, even at relatively high frequencies, a relatively low transfer impedance can still be ensured. High frequencies can arise, for example, during switching operations of the switching elements 202 in an inverter 200.Furthermore, at least one of the contact elements 302 may comprise a relatively noble material (e.g. gold or silver). Thus, a relatively low DC resistance can be made possible even at relatively low frequencies.Thus, a contact arrangement 300 for screen transfer of the shielding 304 of an electrical line 221 may be provided, comprising a plurality of contact elements 302 distributed over the perimeter of the shielding 304. By providing a plurality of circumferential contact elements 302, a relatively low transfer impedance can be made possible even at relatively high frequencies. Only a subset of the contact elements 302 (optionally only a single contact element 302) may comprise a noble metal to provide a low junction resistance. Thus, a relatively low DC resistance can be made possible (for relatively low frequencies).Typically, a relatively low contact resistance or transition resistance of the entire screen transfer can already be produced with a single noble contact element 302. All further contact elements 302 may be made of less noble material such as a copper-based alloy. Noble materials are, for example, gold and silver or coatings thereof.As the frequency of the transmitted current increases, the required number of contact elements 302 that must be distributed over the circumference of the shielding 304 typically also increases. However, these contact elements 302 may be made of a base material.In the case of a transmitted current having a frequency of, for example, 0 Hz, only the DC resistance, which is essentially determined by the one or more contact elements 302 having a noble material, acts. The use of multiple noble contact pads 302 typically does not cause a substantial reduction in DC resistance.For a transmitted current with a frequency of 2 MHz, for example, a uniform distribution of (base) contact elements 302 over the circumference of the shielding 304 is typically advantageous in order to enable a low transfer impedance. If, for example, only a single contact element 302 (i.e. only a single contact point) were present, then the entire current would flow via this contact point. This may lead to an asymmetry of the Farday cage provided by the shielding 304, and thus to a disturbance of the EMC.Typically, the distance between adjacent contact elements 302 should be reduced as the frequency of the transmitted current increases. In this case, the relevance of the transition resistance at the individual contact elements 302 (or contact points) decreases with increasing frequency. On the other hand, the relevance of a uniform distribution of the contact elements 302 over the circumference increases with increasing frequency. As the frequency increases, the amplitude of the transmitted current typically decreases. As a result, the minimum distance required between the contact elements 302 decreases to shield the transmitted current, as the current with the relatively small amplitude could otherwise skip through the gaps between the contact elements 302.FIG. 3 ashows a contact arrangement 300 for a screen transfer as part of a plug component 310 for a plug connection 231. The contact arrangement 300 comprises a plurality of contact elements 302 evenly distributed over the perimeter of the shielding layer 304. Between two adjacent contact elements 302 there is a void space or a void region 303 into which a complementary contact element of a complementary plug-in component of the plug-in connection 231 can be inserted. Thus, an electrically conductive connection can be established between at least one contact element 302 of a first plug component 310 (e.g. a plug) and at least one contact element of a complementary second plug component (e.g. a socket).The contact elements 302 are distributed over the entire circumference of the shielding layer 304 in order to enable reliable shielding transfer even at relatively high frequencies. In this case, the number of contact elements 302 typically increases with increasing frequency.A subset of the contact elements 302 (e.g. only exactly one contact element 302) has a lower contact or transition resistance than the other contact elements 302. The one or more contact elements 302 of this subset may be referred to as low-impedance and / or noble contact elements 302. The contact (DC) resistance of the one or more noble contact elements 302 may be 10%, 20%, 50% or more below the contact (DC) resistance of the other (non-noble) contact elements 302. By providing at least one noble contact element 302, reliable screen transfer at low frequencies (in particular at a direct current) can be ensured.The plug-in component 310 illustrated in FIG. 3 afurther comprises one or more contact parts 301 for contacting one or more electrical lines 221 surrounded by the shielding layer 304.It is thus possible to enable screen transfer with a relatively small number of noble contact elements 302 (preferably only a single noble contact element 302). This allows reliable and cost-effective screen transfer to be effected.The present invention is not limited to the exemplary embodiments shown. In particular, it should be noted that the description and figures are intended to illustrate only the principle of the proposed methods, apparatuses and systems.

Claims

Contact arrangement (300) for transferring a shielding layer (304), which surrounds a first component, in particular an electrical line (221), to a shielding of another component (200, 203); wherein - the contact arrangement (300) comprises a plurality of contact elements (302), which are each designed to contact the shielding of the other component in an electrically conductive manner; - the contact elements (302) are distributed over a circumference of the shielding layer (304); and - a first subset of the contact elements (302) is designed to each enable a contact resistance to the shielding of the other component (200, 203), which contact resistance is 10% lower, 20%, 50% or more lower than a contact resistance enabled by a respective contact element (302) of a complementary second subset of the contact elements (302).Contact arrangement (300) according to Claim 1, wherein - the contact resistance comprises an impurity layer portion which is brought about by an impurity layer formed on a surface of a contact element (302); and - a contact element (302) of the first subset has a lower susceptibility to the formation of an impurity layer than a contact element (302) of the second subset.Contact arrangement (300) according to one of the preceding claims, wherein - the contact resistance comprises a close resistance component which is caused by a roughness of the surface of a contact element (302); and - a contact element (302) of the first subset has a smaller roughness, in particular a smaller average roughness, than a contact element (302) of the second subset.Contact arrangement (300) according to one of the preceding claims, wherein a contact element (302) of the first subset has a surface area for contacting the shielding of the other component (200, 203) that is greater by 10%, 20%, 50% or more than a contact element (302) of the second subset.Contact arrangement (300) according to one of the preceding claims, wherein - at least the surface of a contact element (302) of the first subset comprises a noble metal, in particular gold and / or silver; and - a contact element (302) and / or the surface of a contact element (302) of the second subset comprises no noble metal, in particular no gold and / or silver.Contact arrangement (300) according to one of the preceding claims, wherein the first subset comprises exactly one contact element (302) and wherein the second subset comprises the remaining contact elements (302).Contact arrangement (300) according to one of the preceding claims, wherein - the contact arrangement (300) comprises 10, 20 or more contact elements (302) arranged distributed over the perimeter of the shielding layer (304); and / or - the contact elements (302) are arranged distributed uniformly over the perimeter of the shielding layer (304).Contact arrangement (300) according to one of the preceding claims, wherein - a void region (303) is arranged between two directly adjacent contact elements (302); and - the void region (303) is configured to receive a contact element of the shielding of the other component (200, 203), such that an electrically conductive connection is formed between the contact element of the shielding of the other component (200, 203) and the two directly adjacent contact elements (302).Plug-in component (310) for a plug-in connection (231) of an electrical line (221) with another component (200, 203), wherein the electrical line (221) is surrounded by a shielding layer (304); wherein the plug-in component (310) comprises - at least one contact part (301) for contacting the electrical line (221) with the other component (200, 203); and - a contact arrangement (300) according to one of the preceding claims for contacting the shielding layer (304) with a shielding of the other component (200, 203).Plug-in component (310) according to claim 9, wherein - the plug-in component (310) is formed as a plug; and - the contact elements (302) of the contact arrangement (300) are formed such that the contact elements (302) can be plugged together with contact elements of a complementary plug-in component of the plug-in connection which are arranged in a complementary manner.Vehicle (120), comprising - an electrical line (221) for transmitting electrical energy to an electrical load (200, 203) of the vehicle (120); and - a plug-in component (310) according to one of Claims 9 to 10 for electrically contacting the electrical line (221) with the electrical load (200, 203).

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