WO2009065645A1

WO2009065645A1 - Electrical plug-in contact of an electric drive system

Info

Publication number: WO2009065645A1
Application number: PCT/EP2008/062675
Authority: WO
Inventors: Peter Bucher; Volker Hartmann
Original assignee: Continental Automotive Gmbh
Priority date: 2007-11-20
Filing date: 2008-09-23
Publication date: 2009-05-28
Also published as: DE102007055235B3

Abstract

The invention relates to an electrical plug-in contact (1) of an electric machine (23, 25) of an electric drive system (20) for a motor vehicle, particularly a hybrid vehicle. Said electrical plug-in contact (1) comprises a plug-in housing (8) with a connection element (10, 12) that can be contacted from outside and is connected in an electrically conducting manner to a terminal (4, 6) of the electric machine (23, 25). The plug-in housing (8) at least partly surrounds an electrical connecting lead (9) between the connection element (10, 12) and the machine terminal (4, 6) such that a heat sink is formed.

Description

description

Electrical plug contact of an electric drive system

The present invention relates to an electrical plug contact of an electrical machine of a drive system of a motor vehicle, in particular of a hybrid vehicle.

In electrical connections of electric drive systems in hybrid vehicles supply connections are necessary, which are suitable for high voltages of currently, for example, 300 volts and for high currents. This applies in particular to the electrical machines used in hybrid drive configurations (hybrid drives) in motor vehicles.

As a central problem, the relatively high temperatures (ambient or surface temperatures) in the area of the power actuators and in the region of the winding head of the machine have been exposed to which the respective electrical connections are exposed. Nevertheless, the electrical connections should be quickly and easily connected to prevent obstruction of the production processes and to keep the cost of maintenance as low as possible. At the same time, the electrical connections should be producible and mountable at a reasonable cost.

In electrical drive technology, in particular in hybrid technology for motor vehicles, screw connections and connections can be used which, however, do not meet the desired requirements with regard to time-saving contacting and cost-effective manufacturability as well as service and maintenance.

The invention is therefore based on the object to provide a suitable for high-voltage and / or high-current drive systems of motor vehicles plug contact. A corresponding connector system with such a connector contact and a suitable pluggable mating contact should also be quick and easy to use or assemble and inexpensive to produce.

This object is achieved by the features of claim 1. For this purpose, an electrical plug contact is provided with a plug housing and with a contactable from the outside connecting element, which is in electrically conductive connection with a terminal of the electrical component of the drive system. The plug housing surrounds an electrical connection line between the connection element and the system, component or machine-side connection to form a heat sink for cooling the plug contact. Plug-in contact is understood to mean both a plug contact (male) and a socket contact (female).

The invention is based on the consideration that electrical plug-in contacts or connection systems can be used as high-voltage connection in electric drive systems of motor vehicles and hybrid vehicles even in areas of high ambient or surface temperatures, if the current carrying capacity can be increased for a given conductor and / or contact cross-section. Since the current-carrying capacity of a commercially available plug-in contact with conventional surface quality continuously decreases with increasing temperature due to their temperature dependence and always drops independently of the conductor cross-section at a certain temperature value of typically about 170 ⁰ C to zero, can by targeted cooling of the plug contact whose current load capacity to higher ambient temperatures of z. B.

200 ° C shifted and / or the surface or contact temperature to a temperature level with increased current carrying capacity can be reduced.

Now, those electrical components of a hybrid propulsion system whose high voltage terminals are exposed to high ambient temperatures are typically air or fluid cooled. Due to the cooling, especially in the area of Internal combustion engine, the heat generated due to high operating temperatures ambient heat or in the range of power actuators dissipated there due to occurring power losses heat (heat loss). These cooling points are therefore particularly suitable for providing a heat sink for a connection provided or arranged there, which causes an increase in current carrying capacity. The use of these heat sinks in turn therefore not only allows the use of comparatively easy to handle plug contacts. Rather, due to optimized cooling due to the heat sink achieved by the thermal decoupling of the plug contact from the local hotspots, z. B. from the machine-side winding head, the possibility of reducing the contact cross-section.

In an advantageous embodiment, therefore, the plug housing is connected to a housing portion of a cooled electrical component. When using the plug-type contact on an electrical machine of the drive system or hybrid drive, at least one line section of the electrical connection line is suitably thermally coupled to the housing section of the electrical machine. The machine housing of the electrical machine is usually cooled by means of a fluid. As a result of the thermal connection of the connecting line or its line section to the housing portion of the particular water-cooled machine housing, the heat sink is introduced into the connector housing in a particularly simple and reliable manner.

The heat sink is created by a targeted heat dissipation within the plug housing along the connecting line in or on the cooled machine housing. The heat sink introduced into the plug housing and thus into the machine-side plug-in contact already effects, in a simple and reliable manner, sufficient thermal decoupling of the externally contactable connection or connection element of the plug contact from the machine-side connection. This in turn is a counter contact (male or female), which is electrically and / or mechanically mounted to complete the plug connection system to the terminal or to the connection element of the plug contact, also thermally decoupled. In other words, as a result of the introduction of the heat sink into the plug contact, heat conduction of the operationally high temperatures via the corresponding machine-side phase connection to the plug connection system or to the respective plug or counter contact is avoided.

In an expedient development, a thermally conductive connection element is arranged between the connection line and the machine-side housing section. The connection element is electrically insulating and expediently elastic or plastically deformable. It is clamped within the plug-in housing of the plug-in contact between the connecting line or the corresponding line section and the machine-side housing section.

The connection line or its line section is therefore located in the connection element with deformation of the connection element. Alternatively, the connection element can also be designed in the form of a solid encapsulation or encapsulation of the connection line or its line section. Preferably, the line section, i. H. at least this region of the connecting line pressed by means of a pressure element against or against the connecting element.

An embodiment of the invention will be explained in more detail with reference to a drawing. Show:

1 shows schematically a drive system of a hybrid vehicle with electrical high-voltage components, and Figure 2 shows a schematic sectional view of the structure of an electrical plug-in contact with incorporated heat sink. Corresponding parts are provided in both figures with the same reference numerals.

FIG. 1 schematically shows a drive system 20 of a motor vehicle with a combustion engine 21, which is also referred to below as a hybrid drive system or hybrid drive, and which has a drive shaft 24, eg, a gearbox 22 connected to a first electric machine 23. B. the front axle of the hybrid drive system 20 coupled. A second electric machine 25 is analogous via a gear 26 with a further drive shaft 27, z. B. with the rear axle of the hybrid vehicle or hybrid drive 20 coupled. The electrical machines 23, 25 are, for example, synchronous or asynchronous machines.

As electrical and / or electronic components, which are connected to each other and to the electric machines 23, 25 via high-voltage lines 28, 29, the hybrid drive system 20, in addition to the electric machines 23, 25, essentially comprises a cooled power actuator in the form of a converter unit 30 a high-voltage battery (eg 300V battery) 31 associated relay or contactor (main contactor) 32, an electric air conditioner 33 and a heater 34 and a 230V portable AC power connection 35 on. About Niedervoltleitungen 36 are a 12V battery 37 and

Low-voltage or low-voltage loads 38 connected to the inverter unit 30 and to a central vehicle or vehicle power supply control part 39 which is connected via low-voltage signal lines 40 to the inverter unit 30 and the internal combustion engine 21 and to the high-voltage battery 31 with integrated contactor 32 ,

The converter unit 30, which is connected to the two electrical machines 23, 25 via corresponding signal lines 40, comprises in particular a discharge unit 41, one or more inverters 42 and, in general, one Converter (converter) 43, in particular a DCDC converter. The vehicle or on-board control part 39 comprises a higher-level vehicle control 44, which includes a motor control unit 45, an energy management system 46 and a drive control unit. 47 are subordinate.

With the electric machines 23,25, the electrical or electronic components are connected via high-voltage terminals, which are designed as plug contacts 1. Thus, the first electric machine 23 is electrically connected via a high-voltage or high-voltage line 28 to a converter unit 30. For this purpose, a machine-side plug contact 1 and a converter-side plug contact 1 'are provided. Analogously, the second electrical machine 25 is electrically connected via a high-voltage line 28 to the converter unit 30, to which in turn a machine-side plug contact 1 and a converter-side plug contact 1 'are provided.

The schematic representation of Figure 2 illustrates such an electrical plug contact 1, which allows contacting of the operationally thermally loaded electrical machine 23,25 or other electrical aggregate of the drive system 20 by means of a plug connection. Of the electrical machine 23 and 25, only one hereinafter referred to as the machine-side housing portion section of a housing 2 can be seen, the fluid-cooled, z. B. is cooled with water and this example, a number of fluid channels 3 has.

Through the machine-side housing section 2 phase or connecting lines 4 are guided, which is realized in the embodiment shown by openings 5 suitable size. The electrical machine has a plurality of electrical connection lines 4, which are in particular winding wire connections of stator windings. Of these phase or connecting lines 4 is only a single line visible, noticeable. The line end 6, referred to below as the machine-side connection, of the respective connection lines 5 opens into a cavity 7, which is formed by a preferably shielded plug-in or plug housing 8.

The plug housing 8 surrounds an electrical connecting line 9 between the machine-side terminal 6 and a connecting element 10. The connection between the machine-side terminal 6 and the connecting line 9 is designed as a welded or crimped connection.

The connection element 10 is formed by a socket 11 with a contact lug or a conductor contact 12. This is designed in the form of a round or flat conductor contact and may be part of the connecting line 9 or connected to this electrically conductive. The contact lug or the conductor contact 12 is arranged in the socket 11 touch safe (finger-safe).

The connecting line 9 is expediently designed as an electrical flat conductor, which is guided on the one hand via the conductor or terminal contact 12 of the socket 11 to the outside and on the other hand largely over its entire, hereinafter referred to as line section 13 length within the plug housing 8 is arranged. There lies the line section 13 of the connecting line 9 with a flat side on a connection element 14. This in turn can lie flat on the outer side of the machine-side housing 2 facing the plug housing 8, and thus the cavity 7 enclosed therewith, or be applied there.

The connection element 14 is in particular a highly thermally conductive and electrically insulating silicone polymer film which is clamped within the plug housing 8 of the plug contact 1 between the connecting line 9 or the corresponding line section 13 and the machine-side housing section 2. Such a connection element (Gap Päd) 14 is deformable and thus compensates occurring tolerances, Hö- hen differences and column. It nestles optimally against the surface of the connecting line 9 or the machine-side housing section 2. In principle, the connection element 14 may also be realized as an electrically insulating heat-conducting paste, in particular a flexible or deformable, nonconductive heat-conducting disk or as a casing, encapsulation or coating of the connection line 9.

In the formed between the plug housing 8 and the machine-side housing portion 2 cavity 7 of the plug contact 1, a pressure element 15 is introduced. By means of the pressure element 15 there is a controlled pressing of the connecting line 9 or its line section 13 in the resilient material of the mechanically deformable Anbindungsele- element 14. The connecting line 9 or its line section 13 is pressed into the connection element 14 and can thus practically completely submerge in this ,

As a result, a particularly good heat transfer between the connecting line 9 and the operationally cooled

Guaranteed housing portion 2 and thus introduced a reliable heat sink in the plug housing 8 and in the plug contact 1. In this way, the outwardly guided connection element 10 and in particular the conductor contact 12 of the plug contact 1 is largely shielded from the thermal load. In the case of a partial encapsulation of the connecting line 9 or its line section 13, the connection element 14 and the pressure element 15 can also be made in one piece or in one piece and thus as part of a combined connection and pressure element 14,15.

It is possible by means of the heat sink to be able to use available and mechanically and electrically suitable plug-in contacts 1 for the special application with high adjacent or ambient temperature (thermal load). Within the plug-in contact 1, the increased temperature can be lowered so far and thus the heat input into the plug-in contact 1 can be correspondingly reduced or reduced. avoid that the plug contacts 1 are no longer exposed to an inadmissibly high temperature.

The heat sink is therefore preferably formed on a housing section 2, which, in any case, must be cooled in the region of the winding head owing to the high temperatures of the electric machine, for example 180 ^° C. Thus, it is customary and / or necessary in particular for hybrid vehicles to cool the electric drive assemblies and power components or actuators 30, in particular by means of water-cooled or air-cooled housing regions. In addition, in the plug-in contact 1 or in the connector system with such a plug contact 1 and the associated plug mating contact (not shown) resulting heat due to the invention created heat sink also - at least partially - dissipated.

Due to the increased current carrying capacity of the plug-in contact 1 as a result of the cooling or creation of a heat sink, it can be used for the desired purpose of the high-voltage or high-current connection with a comparatively small contact cross-section.

Claims

claims

1. Electrical plug contact (1) of an electrical machine (23,25) of an electric drive system (20) of a motor vehicle, with a plug housing (8) with a contactable from the outside connecting element (10,12), in electrically conductive connection with a connection (4, 6) of the electrical machine (23, 25), wherein the plug housing (8) has an electrical connection line (9) between the connection element (10, 12) and the connection (4, 6), forming a Heat sink at least partially surrounds.

2. Electrical plug contact (1) according to claim 1, characterized in that the plug housing (8) with a machine-side housing portion (2) of the electric machine of the drive system (20) is connected.

3. Electrical plug contact (1) according to claim 2, characterized in that at least one line section (13) of the electrical connection line (9) to the housing portion (2) is thermally coupled.

4. Electrical plug contact (1) according to claim 2 or 3, characterized in that between the connecting line (9) and the machine-side housing portion (2) a thermally conductive and electrically insulating connection element (14) is arranged.

5. Electrical plug contact (1) according to claim 4, characterized by a connection element (14) in which at least the line section (13) of the connecting line (9) rests.

6. Electrical plug contact (1) according to claim 4, characterized in that the connecting element (14) is deformable, and that the line section (13) of the connecting line (9) with deformation of the connecting element (14) rests in this.

7. Electrical plug contact (1) according to one of claims 4 to 6, characterized in that at least the line section (13) of the connecting line (9) by means of a pressure element (15) against the connecting element (14) is pressed.

8. Electrical plug contact (1) according to one of claims 1 to 7, characterized in that the connection element (10,12) by a conductor contact (12), in particular by a flat conductor or round contact, is formed.