METHOD AND DEVICE FOR OPERATING A SWITCHING ELEMENT

Abstract

The invention relates to a method (10) and to a device (ALE) for operating a switching element (LHS), said method comprising the following steps: a temperature (Tmp) of the switching element (LHS) is determined (22) and said switching element (LHS) is operated (26) in accordance with the determined temperature (TmP).

Claims

1. A method (20) for operating a switching element (LHS), comprising the following steps: determining (22) a temperature (Tmp) of the switching element (LHS), operating (26) the switching element (LHS) depending on the determined temperature (Tmp).

2. The method as claimed in claim 1, comprising the further step of: determining (23) a permissible load current (Iz) through the switching element (LHS) depending on the determined temperature (Tmp), wherein the switching element (LHS) is operated using a load current (I) that is not greater than the permissible load current (Iz).

3. The method as claimed in claim 1, comprising the further steps of: comparing (24) the determined temperature (Tmp) with a temperature threshold value (Tsw), heating (25) the switching element (LHS) as long as the determined temperature (Tmp) is lower than the temperature threshold value (Tsw).

4. The method as claimed in claim 3, characterized in that the switching element (LHS) is heated (25) by a predefinable load current (Iv) through the switching element (LHS).

5. The method as claimed in claim 3, comprising the further step of: when the determined temperature (Tmp) is greater than the temperature threshold value (Tsw), operating (26) the switching element (LHS) using a load current (I) that is not greater than a predefined maximum load current (Imax).

6. The method as claimed in claim 5, comprising the further step of: providing an overvoltage network, to limit a voltage potential that arises at the predefined maximum load current (Imax).

7. A device (ALE) for operating a switching element, which device is configured to perform the method (20) as claimed in claim 1.

8. An electrical system (10), comprising a device (ALE) as claimed in claim 7 and at least one switching element (LHS) for switching a load current (I) within a vehicle.

9. A non-transitory computer readable medium containing a computer program, configured to perform all the steps of the method (20) as claimed in claim 1.

10. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The invention will be described in more detail below with reference to a few figures, in which:

[0030] FIG. 1 shows a schematic illustration of an electrical system.

[0031] FIG. 2 shows a method for operating a switching element.

DETAILED DESCRIPTION

[0032] FIG. 1 shows a schematic illustration of an electrical system. The electrical system 10 comprises at least one switching element LHS, in particular a power semiconductor switch, which conducts a current I from the potential T+ to the potential T− in the closed state, and an actuation logic unit ALE for actuating the switching element LHS. A temperature sensor is provided to determine the temperature Tmp. The actuation logic unit ALE actuates the switching element depending on the determined temperature Tmp. Furthermore, a comparator unit V for comparing the determined temperature Tmp with a predefinable temperature threshold value Tsw is illustrated. The comparator V is connected to the actuation logic unit ALE. The actuation logic unit ALE can determine a permissible load current Iz depending on the determined temperature Tmp. The temperature Tmp can be supplied, as illustrated, to the actuation logic unit ALE by means of the comparator V, or else can be read in directly by the actuation logic unit ALE.

[0033] FIG. 2 shows a method 20 for operating a switching element LHS. The method begins with step 21. In step 22, a temperature Tmp of the switching element LHS is determined. In step 23, a permissible load current Iz through the switching element LHS can be determined depending on the determined temperature Tmp. In step 24, the determined temperature Tmp can be compared with a temperature threshold value Tsw. As long as the determined temperature Tmp is lower than the temperature threshold value Tsw, the method can branch off to step 25. In step 25, the switching element LHS is heated. Said heating can take place, in particular, by means of operating the switching element LHS using a low load current I. The method branches off from step 25 back to step 22, where the temperature Tmp is determined again. In step 26, the switching element LHS is operated depending on the temperature Tmp. In this case, the load current I through the switching element LHS is, in particular, not greater than the permissible load current Iz or, if the determined temperature Tmp is greater than the temperature threshold value Tsw, the load current I through the switching element LHS is not greater than the maximum load current Imax. The method ends with step 27.