METHOD FOR OPERATING A VEHICLE

Abstract

A method for operating a vehicle comprises operating an electric machine and an internal combustion engine as the drive units, by which a total power is generated in synchronous operation for the driving of the vehicle, wherein one portion of the power of the electric machine and one portion of the power of the internal combustion engine is set in dependence on the temperature of at least one of the drive units in the total power for the driving of the vehicle.

Claims

1. A method for operating a vehicle, comprising: operating an electric machine and an internal combustion engine as drive units, by which a total power is generated in synchronous operation for the driving of the vehicle, wherein one portion of the power of the electric machine and one portion of the power of the internal combustion engine is set in dependence on the temperature of at least one of the drive units in the total power for the driving of the vehicle.

2. The method according to claim 1, wherein the portion of the power of the internal combustion engine in the total power is set to be greater than the portion of the power of the electric machine.

3. The method according to claim 1, wherein a definable maximum power is provided by the internal combustion engine and a residual power is provided by the electric machine, the residual power of the electric machine being set from the total power of the drive units minus the maximum power of the internal combustion engine.

4. The method according to claim 1, wherein a portion of the power of the electric machine in the total power is increased when the portion of the power of the internal combustion engine is decreased accordingly.

5. A system for operating a vehicle, comprising: an electric machine and an internal combustion engine as drive units, which are adapted to generating a total power in synchronous operation for the driving of the vehicle, wherein the system comprises at least one thermometer and a controller, and the at least one thermometer is adapted to measure a temperature of at least one drive unit, while the controller is adapted to set one portion of the power of the electric machine and one portion of the power of the internal combustion engine in dependence on the temperature of at least one of the drive units in the total power for the driving of the vehicle.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0022] Embodiments are presented schematically with the aid of the drawings and described schematically and in detail with reference to the drawings.

[0023] FIG. 1 shows in schematic representation a vehicle comprising one embodiment of a system.

[0024] FIG. 2 shows in schematic representation a diagram with operational parameters when implementing one embodiment of a method.

DETAILED DESCRIPTION

[0025] The figures shall be described taken together. The same reference numbers pertain to the same components.

[0026] The vehicle 20 shown schematically in FIG. 1, such as a motor vehicle, comprises an electric machine 22 and an internal combustion engine 24 as its drive units, forming a drive system 26 for the propulsion of the vehicle 20. The embodiment of the system described herein comprises at least one thermometer 28, which is associated with at least one of the two drive units and is adapted to measure its temperature. Furthermore, the system comprises a controller 30, which is adapted to monitor and thus control and/or regulate methods as described herein, as explained with the aid of the diagram in FIG. 2.

[0027] The diagram in FIG. 2 has an abscissa 2, along which is plotted the rotary speed of the drive units in revolutions per minute, and an ordinate 4, along which is plotted the power of a respective drive unit and that of the entire drive system in kW. In the diagram, a first area represents a relaxation region 6 of the electric machine 22, being bounded at the top by a broken-line curve 8 for a maximum power of the electric machine 22 and at the bottom by a solid-line curve 9 for a minimum power of the electric machine 22. Furthermore, a second area represents a relaxation region 10 of the internal combustion engine 24, being bounded at the top by a solid-line curve 12 for a maximum power of the internal combustion engine 24 and at the bottom by a broken-line curve 13 for a minimum power of the internal combustion engine 24. A total target maximum power of the drive system 26 is likewise represented here by a curve 14. The result is the maximum power per curve 14 for a particular rotary speed, such as that from the sum of the maximum power of the internal combustion engine 24 (curve 12) and the minimum power of the electric machine (curve 9). Yet other powers of the internal combustion engine 24 and the electric machine 22 situated between the respective maximum power and the respective minimum power can also add up to give the target power (curve 14) of the drive system 26.

[0028] Accordingly, the diagram shows the necessary powers of the electric machine 22 and the internal combustion engine 24 with which a given and/or target power of the drive system 26 is achieved. The indicated maximum powers (curves 8, 12) of the two drive units are the powers which can be achieved at most in a particular operational situation at a particular rotary speed.

[0029] In this diagram, both drive units have in idealized manner the same rotary speed along the abscissa 2 at one operating point, such that the wheels of the vehicle 20 are driven with the same rotary speed in a hybrid drive. However, the two rotary speeds of the electric machine 22 and the internal combustion engine 24 may be different at one time, yet be synchronized by a transmission.

[0030] One portion of the power (curve 12 or curve 13) of the internal combustion engine 24 in the total power (curve 14) is set greater than the portion of the power (curve 8 or curve 9) of the electric machine 22. Furthermore, the portion of the power of the electric machine 22 and the portion of the power of the internal combustion engine 24 in the total power for the driving of the vehicle 20 are set in dependence on a temperature of at least one of the drive unit, i.e., that of the electric machine 22 and/or that of the internal combustion engine 24, these temperature being measured by the at least one thermometer 28, there being one thermometer 28 associated with each drive unit.

[0031] It is possible for the power of the internal combustion engine 24 to be reduced (negatively pointing arrow 18), starting from a particular maximum value (curve 12), and at the same time for the power of the electric machine 22 to be increased (positively pointing arrow 16), starting from a particular minimum value (curve 9).

[0032] German patent application no. 10 2021 129143.7, filed Nov. 9, 2021, to which this application claims priority, is hereby incorporated herein by reference, in its entirety.

[0033] Aspects of the various embodiments described above can be combined to provide further embodiments. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled.