Method for operating a motor vehicle

Abstract

A method for operating a motor vehicle, which is equipped with a plurality of wheels and with a plurality of electric machines. Each electric machine can be coupled to at least one wheel and be operated in a plurality of operating modes. The respective electric machines perform rotations in a first engine operating mode in a first direction of rotations. Electric energy is converted to mechanical energy. The at least one wheel is rotated in a forward direction, whereby the vehicle is driven with the at least one wheel. The respective electric machines perform rotations in a second generator operating mode in a second direction of rotations, which is opposite to the first direction of rotations, whereby electric energy is converted to mechanical energy.

Claims

1. A system for operating a vehicle, comprising: a plurality of wheels and with a plurality of electric machines, wherein each electric machine is coupled to at least one wheel and can be operated in a plurality of operating modes; wherein each respective electric machine can perform rotations in a first direction of rotation in a first operating mode so that electric energy is converted to mechanical energy, wherein the at least one wheel can be rotated in a forward direction, whereby the vehicle can be driven with at least one wheel; wherein each respective electric machine can perform rotations in a second engine operating mode in a second direction of rotation that is opposite to the first direction of rotation, wherein electric energy can be converted to mechanical energy, whereby the motor vehicle can be braked with at least one wheel; wherein a third generator operating mode is provided for each respective electric machine, wherein at least one wheel can be rotated in the forward direction, wherein the mechanical energy resulting from the movement of at least one wheel can be converted in the third generator operating mode to electric energy, whereby the motor vehicle can be braked; wherein the system is provided with at least one control device that is provided in the vehicle to control and regulate the plurality of electric machines, which is designed to cause at least one first electric machine in the second generator operating mode and at least one second electric machine to be operated in the third operating mode; and wherein electric energy, which can be converted by at least one second electric machine from mechanical energy can be converted directly by at least one first electric machine to mechanical energy.

2. The system of claim 1, wherein the vehicle is equipped with at least one electric energy storage device, in which can be stored electric energy from at least one electric machine that is converted in the third generator operating mode from mechanical energy, and can be extracted from the electric energy which is converted by at least one electric machine in an engine operating mode to mechanical energy.

3. The system of claim 2, wherein the at least one first electric machine is operated in the second engine operating mode and the at least one second electric machine is operated in the third generator operating mode in the case when an amount of electric energy stored at least in the at least one electric storage device is greater than a definable threshold value.

4. The system of claim 1 wherein the at least one first electric machine is operated in the second engine operating mode and the at least one second electric machine is operated in the third generator operating mode when the vehicle is to be braked.

5. The system of claim 1, wherein the at least one first electric machine is operated in the second engine operating mode and the at least one second electric machine is operated in the third generator operating mode when the vehicle is traveling downhill.

6. The system of claim 1, wherein in the case when the at least one first electric machine is operated in the second engine operating mode and the at least one second electric machine is operated in the third generator operating mode, a torque of the motor vehicle is adjusted.

7. The system of claim 2, wherein in the case when at least one first electric machine is operated in the second engine operating mode and the at least one second electric machine is operated in the third engine operating mode, at least one part of the electric energy that is required from the at least one first electric machine in the second engine operating mode is extracted from the at least one electric energy storage device.

8. The system of claim 2, wherein in the case that the at least one first electric machine is operated in the second generator operating mode and the at least one second electric machine is operated in the third generator operating mode, at least one part of the electric energy that is generated by the at least one second electric machine in the third engine operating mode is stored in the at least one electric energy storage device.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows in a schematic representation a motor vehicle which is provided with an embodiment of the system according to the invention for carrying out an embodiment of the method according to the invention.

DETAILED DESCRIPTION OF THE FIGURES

(2) FIG. 1 shows in a schematic representation a motor vehicle 2, which is equipped with a front axle 4 and with a rear axle 6. In this case, on the front axle 4 is provided a left front wheel 8 and a right front wheel 10. On the rear axle 6 is provided a left rear wheel 12 and a right rear wheel 14. In addition, each wheel 8, 10, 12, 14 is associated with an electric machine 16, 18, 20, 22, wherein to the front left wheel 8 is assigned a front left electric machine 16, to the front right wheel 10 is assigned a front right electric machine 18, to the rear left wheel 12 is assigned a rear left electric machine 20, and to the rear right wheel 14 is assigned a rear right electric machine 22. In addition, to the wheels 8, 10, 12, 14 and the electric machines 16, 18, 20, 11, the vehicle 2 comprises as further components at least one electric energy storage device 24, wherein only one such an electric energy storage device 24 is shown here, at least one sensor 26 and at least one control device 28. Monitoring to determine whether the vehicle 2 is traveling downhill, etc., is performed with the at least one sensor 26.

(3) At the same time, at least one of the named components of the vehicle 2 can be also designed as a component of an embodiment of the system 30 according to the invention, and used for carrying out the method according to the method of this invention. The control device 28 is designed to carry out a function, for example an operating mode, or to control and/or regulate with at least one of the component of the vehicle 2, for example one of the named electric engines 16, 18, 20, 22 and/or the system 30, as well as to control at least one step of the embodiment of the method.

(4) In this case, each electric engine 16, 18, 20, 22 can be operated in different operating modes. At the same time, a respective electric machine 16, 18, 20, 22 can be operated as an engine, wherein the at least one electric component of the electric machines 16, 18, 20, 22 provides electric energy, which is converted by respective electric machines 16, 28, 20, 22 to mechanical energy, so that the wheels 8, 10, 12, 14 which are associated with and/or coupled to the respective electric machines 16, 18, 20, 22 are set in motion. In this case it is possible for respective wheels 8, 10, 12, 14 to be operated during the operation of the associated electric machines 16, 18, 20, 22 as an engine either in the first operation mode in a first direction or the forward direction, or to be impacted mechanically in a second operating mode in a second rotational direction or the reverse direction.

(5) At the same time is possible to provide the electric energy of the respective electric machines that is required for this purpose from the at least one electric energy storage device 24 as will be explained later in more detail, namely to provide it from at least one other electric machine 16, 18, 20, 22 which are used as components of the vehicle 2 and/or of the system 30.

(6) In a further operating mode, namely the third operating mode, the respective electric machines 16, 28, 20, 22 are operated as a generator, wherein mechanical energy which results from the rotations of each wheel 8, 10, 12, 14, which are associated with the electric machines 16, 18, 20, 22, is converted to electric energy and it is provided to at least one other component of the vehicle 2 and/or of the system 30, which is to say to an electric energy storage device 24 and/or another electric machine 16, 18, 20, 22.

(7) In the embodiment of the method, at least one first electric machine 16, 18, 20, 22 is operated in the second operating mode, namely an engine operating mode, and at least one second electric machine 16, 18, 20, 22 is operated in the third operating mode, namely a generator operating mode, wherein electric energy from at least one second electric machine 16, 18, 20, 22 is obtained from mechanical energy and converted directly, immediately and at the same time from the at least one first electric machine 16, 18, 20, 22 to mechanical energy.