DE102018002166A1 - A method for charging an energy storage of a motor vehicle, and motor vehicle - Google Patents

Abstract

The invention relates to a method for charging an energy store (16) of a motor vehicle (10) with electrical energy, in which at least one electrical machine (18) of the electric motor (10) designed to drive the motor vehicle (10) and to be supplied with electrical energy by the energy store (16) Motor vehicle (10) receives mechanical energy, which is converted by the electric machine (18) into electrical energy provided by the electric machine (18), the energy storage (16) supplied and stored in the energy storage (16), wherein the electric machine (18) receives the mechanical energy provided by a relative to the motor vehicle (10) external device (20) and converts it into electrical energy.

Description

The invention relates to a method for charging an energy store of a motor vehicle according to the preamble of patent claim 1. The invention also relates to a motor vehicle according to the preamble of patent claim 5.

Such methods for charging energy storage devices of motor vehicles and such motor vehicles are already well known from the general state of the art and in particular from the production of standard vehicles. In the method, at least one designed to drive the motor vehicle and supplied from the energy storage with electrical energy electrical machine of the motor vehicle with mechanical energy, so that the electric machine receives mechanical energy. Since the electric machine is designed to drive the motor vehicle, the electric machine is also referred to as a traction machine. The mechanical energy received by the electric machine is converted into electrical energy by the electric machine. The electrical energy is provided by the electric machine, supplied to the energy storage and stored in the energy storage, whereby the energy storage is charged with the electrical energy.

Usually, such a charging of the energy storage is carried out in the context of a so-called recuperation, in the context of which kinetic energy of the moving motor vehicle is converted into mechanical energy. Thus, the electric machine is driven by the mechanical energy received from the electric machine while the motor vehicle is moving. In this case, the electric machine is always driven by the motor vehicle itself or by means of components of the motor vehicle itself and is supplied with the mechanical energy.

Furthermore, the DE 10 2015 225 441 A1 an energy storage cell balancing system for a vehicle disposed in a high-voltage storage, the high-voltage storage having a plurality of structurally autonomous running energy storage modules.

Moreover, from the DE 10 2009 024 628 A1 a charging method for at least one electrical energy storage in a motor having at least one electric drive motor vehicle known.

Object of the present invention is to develop a method and a motor vehicle of the type mentioned in such a way that the energy storage can be charged particularly cheap in a very short time.

This object is achieved by a method having the features of patent claim 1 and by a motor vehicle having the features of patent claim 5. Advantageous embodiments with expedient developments of the invention are specified in the remaining claims.

In order to further develop a method specified in the preamble of claim 1 such that the energy storage can be charged in a particularly short time and particularly favorable, it is provided according to the invention that the electric machine receives the mechanical energy provided by a device external to the motor vehicle and converted into electrical energy, in particular while the motor vehicle is stationary, that is, while the motor vehicle is at a standstill and thus does not move. In other words, it is provided in the context of the inventive method that the mechanical energy that is received by the electric machine is not or not only provided by the motor vehicle itself, but the mechanical energy for driving the electric machine is from that of the Motor vehicle different and with respect to the motor vehicle external device provided and supplied, for example, the electric machine directly or via at least a portion of the motor vehicle. By the feature that the mechanical energy provided by the device is supplied directly to the electric machine, it is to be understood that the electric machine directly supplies the mechanical energy provided by the device, thereby bypassing components of the motor vehicle other than the electric machine Device receives. By the feature that the mechanical energy supplied by the device is supplied to the electric machine via at least part of the motor vehicle, it is to be understood that at least one or more components of a powertrain of the motor vehicle that are different from the electric motor are used to control those of to transmit the mechanical energy provided with respect to the motor vehicle external device from the device to or on the electric machine.

Usually, it is provided to provide electrical energy for charging energy stores of motor vehicles by means of external power sources with respect to the respective motor vehicle. According to the invention, it is now provided, however, to provide mechanical energy for charging the energy store, which receives mechanical energy from the electric machine and in electrical energy is converted. The mechanical energy for charging the energy storage is not provided by means of the motor vehicle itself, but by means of the device with respect to the motor vehicle external device, whereby the energy storage particularly fast, that can be charged in a short time and very cheap.

The invention is based in particular on the following finding: With the electrification of drive trains of motor vehicles, the pollutant and CO ₂ emissions in the automotive sector are reduced. The energy required for driving the electrical machines of the motor vehicles is usually stored by a storage device designed as a battery. This is used depending on the application (partially electrified, fully electric, combination with fuel cell, passenger cars, trucks, etc.) in different embodiments and with different sized storage capacities.

The storage capacity of storage devices such as batteries is low compared to the energy content of fuel relative to the total weight of the energy storage device (battery versus fuel tank). The charging of an empty battery storage is more or less time-consuming depending on the possible charging power, but much more time-consuming than refilling a fuel tank with, for example, liquid or gaseous fuel. For example, the charging of electric vehicles often requires hours in which the driver can not use his vehicle, which today significantly impairs the acceptance of electrified vehicles.

• - Einsatz von sogenannten Wandboxen mit erhöhter Ladeleistung, wobei eine solche Wandbox auch als Wallbox bezeichnet wird
• - Schnellladesäulen mit erhöhter Ladeleistung
• - Gleichstromladen mittels sogenannter DC-Lader (DC-Charger)

To shorten the charging time of electrified powertrains today, several options are already known. These include:

• - Use of so-called wall boxes with increased charging power, such a wall box is also referred to as Wallbox
• - Fast charging stations with increased charging power
• - DC charging by means of so-called DC-Lader (DC-Charger)

All approaches have in common that the electrical power or the electrical energy is increased when charging to reach a limit. This limit can be the maximum current path of the electrical power network or even the thermal load of individual components. Alternatively, the use of replacement batteries should be considered as known. Replacing a dead battery with a full battery, however, has proven ineffective in practice, as the batteries must be complex integrated into the vehicle architecture of each manufacturer depending on its module kit.

The invention now provides for charging the energy store by means of the electric machine installed in the motor vehicle. For this purpose, the designated also as a traction machine electric machine, for example, designed as a hybrid or electric vehicle motor vehicle is driven by the electrical machine from the outside, that is supplied by means of the external relative to the motor vehicle mechanical power or mechanical energy. The mechanical energy transmitted in this way is converted into electrical energy by appropriate use of the electrical machine in the motor vehicle and stored in the energy accumulator designed, for example, as a battery. In other words, the electrical energy provided by the electric machine is stored in the energy store. The electric machine is, since it is part of the vehicle's powertrain and designed for use with this, ideally suited for charging the vehicle-side, designed for example as a battery energy storage.

In order to drive the electrical machine of the motor vehicle by means of the mechanical energy provided by the device, for example a charging device is used which can be embodied in different embodiments. All embodiments may have in common that transmitted to drive the electric machine torque between the vehicle wheels of the motor vehicle and the electric machine is transmitted to the drive train. Depending on the particular embodiment, an additional coupling may be provided which mechanically separates the vehicle wheels of the motor vehicle, which are generally drivable by the electric machine, from the electric machine for the period of loading. As a result, the electric machine, in particular its rotor can be driven by means of the aforementioned mechanical energy without the vehicle wheels of the motor vehicle being driven.

In a first embodiment, the connection device may comprise a shaft connection of the electric machine. In this case, the electric machine has, for example, the possibility of connecting a shaft to the electric machine by means of a connection suitable therefor, for example a pin, a polygonal profile or the like. This can be done for example via an underbody of the motor vehicle. By means of this shaft, a torque is then transferred to the electrical machine during charging from outside, which converts this mechanical energy into electrical energy Energy converts and stores the latter in the energy store.

In a second embodiment of the charging device, this may have a shaft connection with a differential gear. The necessary for the transmission of torque shaft is connected in the range of the differential gear with the drive train of the motor vehicle.

In a third embodiment, a shaft connection of a drive wheel may be provided. The shaft provided for transmitting the torque is connected in the region of at least one drive wheel of the motor vehicle to the drive train of the motor vehicle. This can for example be done directly on a rim or in the region of a brake disc of the drive wheel.

In order then to supply, for example, the electric machine via the shaft, via the differential gear and / or the drive wheel with the mechanical energy provided by the device so that the electric machine receives the mechanical energy provided by the device external to the motor vehicle, it can be provided. that a vehicle roll, also referred to simply as a roll, is used. Here, the motor vehicle is connected via its connected to the drive train vehicle wheels on at least one driven roller. The same can apply to a device that raises the motor vehicle from the ground in order to allow the wheels to rotate freely, which may be provided for example in wheel hub motors. If, for example, by means of the vehicle roller at least one vehicle wheel of the motor vehicle mechanically connected to the electric machine is driven, the electric machine is driven via the shaft, via the vehicle wheel and / or the differential gear by means of the vehicle roller, whereby the electric machine receives mechanical energy.

The method according to the invention for charging the energy store by means of the mechanical energy to be transmitted externally to the drive train of the motor vehicle provides, for example, a specific operating mode of the motor vehicle. This mode of operation is hereafter called mechanical loading. In the context of mechanical loading, the electric machine mechanically receives at least one torque, which is provided by the device external to the motor vehicle.

• - das Fahrzeug steht bereits über einer geeigneten Antriebsstation, und der Fahrer startet im Anschluss an die Auswahl des Betriebsmodus im Fahrzeug an einem Bedienpult der Antriebsstation den Ladevorgang und die mechanische Verbindung wird in der Folge hergestellt.
• - Das Fahrzeug fährt selbstständig im Anschluss an die Auswahl des Betriebsmodus selbstständig über die Antriebsstation.
• - Das Fahrzeug kommuniziert mit der Antriebsstation, sodass der Ladevorgang nur im Fahrzeug gestattet werden muss.

In order to start the process of mechanical loading, for example, a request by the driver of the motor vehicle is provided. This can drive, for example, to a suitable drive station and activate the mode mechanical loading in the motor vehicle. As a result, the preparations for the mechanical loading are made. This can be done in different ways. The following is conceivable, for example:

• - The vehicle is already on a suitable drive station, and the driver starts after the selection of the operating mode in the vehicle at a control panel of the drive station, the charging process and the mechanical connection is made in the sequence.
• - The vehicle automatically moves on to the drive station following the selection of the operating mode.
• - The vehicle communicates with the drive station, so charging must be permitted only in the vehicle.

After a mechanical connection between the drive station and the drive train of the vehicle, a torque is transmitted to the electric machine at least indirectly or directly from the drive station. Since it is in generator mode, it converts the mechanical energy into electrical energy and stores the latter in the energy store.

• - Das Fahrzeug kommuniziert mit der Antriebsstation, und letztere beendet die Übertragung des Drehmoments und reduziert die Drehzahl der Welle auf Null.
• - Das Fahrzeug kommuniziert nicht mit der Antriebsstation. Die elektrische Maschine verlässt den generatorischen Betrieb, sodass die Antriebsstation, die beispielsweise drehzahlgeregelt betrieben wird, das Antriebsdrehmoment reduziert. Bei Unterschreitung einer bestimmten Drehmomentschwelle schaltet sich die Antriebsstation ab.

The process of mechanical loading can be interrupted by the driver. At the latest when fully charged energy storage, it is automatically canceled, which can be done in different ways. The following is conceivable, for example:

• The vehicle communicates with the drive station, and the latter stops the transmission of torque and reduces the speed of the shaft to zero.
• - The vehicle does not communicate with the drive station. The electric machine leaves the regenerative mode, so that the drive station, which is operated, for example, speed-controlled, reduces the drive torque. When a certain torque threshold is undershot, the drive station shuts down.

• - Größtmögliche Ladeleistung umsetzbar
• - Signifikante Verkürzung der benötigten Ladedauer
• - Steigerung der Kundenakzeptanz von elektrifizierten Fahrzeugen
• - Verglichen zum elektrischen Laden ist die Einrichtung der Infrastruktur bei mechanischem Laden deutlich geringer
• - Keine Verwendung von Ladekabel notwendig (Stolperfallen, Schmutz, Vandalismus)
• - Unabhängigkeit von Energieversorgern zur Errichtung eines flächendeckenden Ladenetzes
• - Vielfältige Möglichkeiten zum Antreiben der Antriebsvorrichtung (elektrisch, motorisch etc.)

By the invention, the charging of the energy storage and thus the electrified motor vehicle in the shortest possible time on favorable terms possible. Further advantages are:

• - Greatest possible charging power feasible
• - Significant reduction in the required charging time
• - Increased customer acceptance of electrified vehicles
• - Compared to electrical charging, the infrastructure of the mechanical charging infrastructure is much smaller
• - No use of charging cable necessary (trip hazards, dirt, vandalism)
• - Independence of energy suppliers for the establishment of a nationwide charging network
• - Various possibilities for driving the drive device (electric, motor etc.)

In order to develop a motor vehicle specified in the preamble of claim 5 type such that the energy storage can be charged very quickly and cheaply, a connecting device is provided according to the invention, via which the electric machine with a relative to the motor vehicle external device coupled and thereby with the of Device provided mechanical energy is supplied. Advantages and advantageous embodiments of the method according to the invention are to be regarded as advantages and advantageous embodiments of the motor vehicle according to the invention and vice versa.

Further advantages, features and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the figure description and / or alone in the single figure can be used not only in the respectively indicated combination but also in other combinations or alone, without the frame to leave the invention.

The drawing shows in the single FIGURE is a schematic side view of an embodied for performing a method according to the invention motor vehicle.

The single FIGURE shows a schematic side view of a motor vehicle 10 , which is designed as a motor vehicle, especially as a passenger car. The car 10 has a drive train 12 on, by means of which the motor vehicle 10 is drivable. This includes the powertrain 12 drivable wheels, of which in the Fig. A wheel designated 14 can be seen. The car 10 is designed as a hybrid or electric vehicle, so that the respective wheel 14 and thus the motor vehicle 10 total can be driven at least electrically.

For this purpose, the motor vehicle includes 10 at least one, for example, as a battery, in particular as a high-voltage battery (HV battery) formed energy storage 16 , in or by means of which electrical energy or electric current can be stored. Furthermore, the motor vehicle includes 10 , especially the powertrain 12 , at least one electric machine 18 , by means of which the at least one wheel 14 and thus the motor vehicle 10 can be driven electrically in total. The electric machine 18 is therefore also called a traction machine. The electric machine 18 is in an engine operation and thus operable as an electric motor. In the engine operation, the electric machine 18 the wheel 14 and thus the motor vehicle 10 drive electrically in total. To the electric machine 18 to operate in the engine operation, the electric machine 18 with in the energy storage 16 stored electrical energy supplied.

The electric machine 18 is also regenerative and thus in a generator mode, that is, as a generator, operable. In the generator mode, the electric machine 18 is mechanically driven by the electric machine 18 receives mechanical energy. This means that the electric machine 18 supplied with mechanical energy. The electric machine 18 converts at least part of the mechanical energy generated by the electrical machine 18 is received into electrical energy by the electric machine 18 is provided in the generator mode. The of the electric machine 18 Provided electrical energy is supplied by the electric machine 18 to the energy store 16 led and into the energy storage 16 stored, causing the energy storage 16 is loaded. In other words, the energy storage 16 with that of the electric machine 18 provided electrical energy, which in the energy storage 16 is stored. As a result, the energy storage 16 loaded.

To now the energy storage 16 To be able to load particularly quickly and cheaply receives the electric machine 18 in the context of a method for charging the energy store 16 from one of the motor vehicle 10 external device 20 provided mechanical energy and converts the mechanical energy that the electric machine 18 from the respect of the motor vehicle 10 external device 20 receives, into electrical energy, that of the electric machine 18 provided. As previously described, that of the electric machine 18 provided electrical energy to the energy storage 16 supplied and stored in this, whereby the energy storage 16 is loaded. For this purpose, the motor vehicle 10, for example, a connecting device 22 on, over which the electric machine 18 with respect to the motor vehicle 10 external device 20 torque transmitting coupled and thereby with that of the device 20 provided mechanical energy is supplied.

The electric machine 18 , in particular its rotor, for example, via a shaft directly with the device 20 connected torque transmitting. If the device 20 now provides at least one torque and thus mechanical energy, then the torque or that of the device can 20 provided mechanical energy via the shaft directly to the electric machine 18 be transferred, so that the electric machine 18 the from the device 20 provided electrical energy, bypassing the rest, from the electric machine 18 different powertrain 12 receives.

Furthermore, it is conceivable that the electric machine 18 with that of the device 20 provided electrical energy via at least one of the electric machine 18 different component of the powertrain 12 is supplied. As the component, for example, a differential gear is used, via which the wheels 14 of the electric machine 18 can be driven electrically. Alternatively or additionally, as the component, one of the wheels 14 or both wheels 14 used. For example, the differential gear and / or the wheels 14 by means of the device 20 powered by the device 20 provided mechanical energy first on the differential gear or on the wheels 14 is transferred, so in the sequence, the electric machine 18 via the differential gear and / or the wheels 14 from the device 20 or from the device 20 powered mechanical energy.

The charging of the energy storage described above 16 preferably takes place while the motor vehicle 10 is at a standstill.

To the energy storage 16 using the electric machine 18 of the motor vehicle 10 To load, for example, a circuit arrangement for the recovery of electrical energy from kinetic energy of the motor vehicle 10 used. Overall, it can be seen that at least one of the device 20 provided mechanical torque to the electric machine 18 is transmitted to thereby gain from externally supplied mechanical energy electrical energy for charging the energy storage 16. Because the device 20 is an external device relative to the motor vehicle 10, the torque or the mechanical energy for charging the energy storage 16 from outside the motor vehicle 10 of the electric machine 18 fed.

The supply of the electric machine 18 with the provided from outside mechanical energy, for example, via a shaft connection to the differential gear, via a shaft connection to at least one of the wheels 14 and / or via a shaft connection to the electric machine 18 , In this way, the energy storage 16 be charged efficiently and effectively, especially during the motor vehicle 10 stands still.

LIST OF REFERENCE NUMBERS

10

motor vehicle

12

powertrain

14

wheel

16

energy storage

18

electric machine

20

contraption

22

connecting device

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015225441 A1 [0004]
• DE 102009024628 A1 [0005]

Claims (5)

Method for charging an energy store (16) of a motor vehicle (10) with electrical energy, in which at least one electric machine (18) of the motor vehicle (10) that is designed to drive the motor vehicle (10) and can be supplied with electrical energy by the energy store (16) receives mechanical energy which is converted by means of the electric machine (18) into electrical energy provided by the electric machine (18), supplied to the energy store (16) and stored in the energy store (16), characterized in that the electrical Machine (18) receives from a relative to the motor vehicle (10) external device (20) provided mechanical energy and converted into electrical energy. Method according to Claim 1 , characterized in that the electrical machine (18) receives the mechanical energy provided by the device (20) directly and thereby bypassing components of the motor vehicle (10) that are different from the electric machine (18) from the device (20). Method according to Claim 1 , characterized in that the mechanical energy provided by the device (20) is transmitted to the electric machine (18) via at least one component of a drive train (12) of the motor vehicle (10) that is different from the electric machine (18). Method according to Claim 3 , characterized in that as the component at least one wheel (14) and / or at least one transmission, in particular a differential gear, and / or at least one shaft of the drive train (12) is used. Motor vehicle (10), with at least one energy storage device (16) for storing electrical energy, with at least one for driving the motor vehicle (10) formed and of the energy storage (16) can be supplied with electrical energy electrical machine (18) which is adapted thereto receive mechanical energy, convert the received mechanical energy into electrical energy, provide the electrical energy and supply it to charge the energy store (16), characterized by a connection device (22) via which the electric machine (18) is moved with respect to the Motor vehicle (10) external device (20) can be coupled and thereby supplied with the mechanical energy provided by the device (20).

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