Method and device for adapting a voltage limit in an onboard electrical system

1. A method for controlling a voltage limit for a maximally permissible operating voltage in an on-board electrical system of a vehicle, comprising:

regulating an actual voltage of the on-board electrical system to a desired voltage, wherein the desired voltage is less than the maximally permissible operating voltage;

one of limiting and short-circuiting the actual voltage if the actual voltage exceeds the maximally permissible operating voltage in the on-board electrical system; and

adapting the voltage limit in dependence on vehicle data by one of raising and lowering the voltage limit, wherein the voltage limit is adapted temporarily from a first value that is above a voltage of a battery of the on-board electrical system to a second value that is above the first value.

2. The method as recited in claim 1 , wherein the vehicle data indicate a speed of the vehicle and the voltage limit is adapted in dependence on the speed.

3. The method as recited in claim 2 , wherein the voltage limit is raised if a predefined speed of the vehicle is exceeded.

4. The method as recited in claim 3 , wherein the voltage limit below the predefined speed is set to a predefined value.

5. The method as recited in claim 4 , wherein the predefined value is below 60 V.

6. The method as recited in claim 1 , wherein a voltage value that indicates a load dump in the on-board electrical system is set in dependence on the voltage limit produced by the adapting.

7. The method as recited in claim 6 , wherein the voltage value that indicates the load dump in the on-board electrical system is in each case above the voltage limit produced by the adapting by a predefined amount.

8. The method as recited in claim 1 , wherein the vehicle data are data that indicate an actuation of a brake pedal, and the voltage limit is adapted in dependence on the actuation of the brake pedal.

9. The method as recited in claim 8 , wherein the voltage limit is raised upon actuation of the brake pedal, and the raised voltage limit is lowered after a predefined period of time after a release of the brake pedal.

10. The method as recited in claim 1 , wherein the vehicle data indicate an acceleration of the vehicle, and the voltage limit is adapted in dependence on the acceleration.

11. The method as recited in claim 1 , wherein:

when the vehicle data indicates an unlocking of an engine hood, the voltage limit is lowered, and

when the vehicle data indicates a locking of the engine hood, the voltage limit is raised.

12. A device for controlling a voltage limit for a maximally permissible operating voltage in an on-board electrical system of a vehicle, comprising:

an arrangement for regulating an actual voltage of the on-board electrical system to a desired voltage, wherein the desired voltage is less than the maximally permissible operating voltage;

an arrangement for one of limiting and short-circuiting the actual voltage if the actual voltage exceeds the maximally permissible operating voltage in the on-board electrical system; and

an arrangement for adapting the voltage limit in dependence on vehicle data by one of raising and lowering the voltage limit, wherein the voltage limit is adapted temporarily from a first value that is above a voltage of a battery of the on-board electrical system to a second value that is above the first value.

13. The device as recited in claim 12 , wherein:

when the vehicle data indicates an unlocking of an engine hood, the voltage limit is lowered, and

when the vehicle data indicates a locking of the engine hood, the voltage limit is raised.