Method and device for protecting an electrical architecture

1. A method for protecting an electrical architecture comprising a protective device provided with a protective fuse that is able to melt in an impaired mode of operation during which a break current, with a magnitude higher than a threshold, flows in the architecture, the method comprising, in a nominal mode of operation, the following:

periodically estimating a temperature of said fuse, and

controlling a magnitude of a useful current flowing in said fuse such that the estimated temperature remains lower than a melting temperature of said fuse,

wherein said controlling the magnitude of useful current reduces the temperature of said fuse to below a threshold fuse temperature, responsive to said periodically estimating the temperature resulting in the estimated temperature of the fuse exceeding the threshold fuse temperature, while at the same time limiting the useful current flowing in said fuse to no more than a second maximum magnitude, and

wherein the threshold fuse temperature is less than the melting temperature of said fuse.

2. The method as claimed in claim 1 , further comprising defining a first limit setpoint for the magnitude of the current at a first maximum magnitude flowing in said fuse.

3. The method as claimed in claim 1 , wherein said controlling comprises defining the second maximum magnitude as a second limit setpoint for the useful current magnitude when the estimated temperature of said fuse is higher than the threshold fuse temperature.

4. The method as claimed in claim 1 , wherein said periodically estimating the temperature of the fuse comprises:

measuring the magnitude of the current flowing in said fuse, and

calculating the temperature of the fuse based on the measured magnitude of the current flowing in said fuse and of a data model linking temperatures with magnitudes relating to said fuse.

5. The method as claimed in claim 1 , wherein said periodically estimating the temperature of the fuse comprises:

measuring the magnitude of the current flowing in a strip of said fuse, and

calculating the temperature of the fuse based on the measured magnitude of the current flowing in the strip of said fuse and of a data model linking temperatures with magnitudes relating to said fuse.

6. The method as claimed in claim 1 , further comprising determining a threshold temperature based on a difference between the melting temperature of the fuse and a temperature variation relating to a power that the fuse is liable to dissipate, the power being lower than a melting power of the fuse.

7. The method as claimed in claim 1 ,

wherein said periodically estimating comprises adjusting a measured or calculated temperature of the fuse based on a determined ambient temperature of said fuse, and/or

wherein said periodically estimating and said controlling are implemented by an analog or PID controller algorithm.

8. A non-transitory computer readable medium storing a computer program that, when executing by a processing unit, causes the computer to execute the method as claimed in claim 1 .

9. The method as claimed in claim 1 , wherein said controlling the magnitude of useful current reduces the temperature of said fuse to below the threshold fuse temperature and to a predetermined stable temperature between the threshold fuse temperature and a hysteresis temperature.

10. The method as claimed in claim 1 , wherein said periodically estimating the temperature of said fuse is performed directly via a temperature sensor positioned to sense temperature of a strip of said fuse.

11. A device for protecting an electrical architecture, the device comprising:

a protective fuse configured to melt in an impaired mode of operation during which a break current, with a magnitude higher than a threshold, flows in the architecture; and

circuitry configured to

periodically estimate a temperature of said fuse in a nominal mode of operation, and

control a magnitude of a useful current flowing in said fuse in the nominal mode of operation such that the estimated temperature remains lower than a melting temperature of said fuse,

wherein the controlling the magnitude of useful current reduces the temperature of said fuse to below a threshold fuse temperature, responsive to the periodically estimating the temperature resulting in the estimated temperature of the fuse exceeding the threshold fuse temperature, while at the same time limiting the useful current flowing in said fuse to no more than a second maximum magnitude, and

wherein the threshold fuse temperature is less than the melting temperature of said fuse.

12. The device as claimed in claim 11 , further comprising:

at least one temperature sensor to sense the temperature of the fuse,

a device to determine an ambient temperature of the fuse and/or at least one device to measure the magnitude of the current flowing in said fuse, and/or

the circuitry is connected to said at least one temperature sensor, to the at least one device to measure the magnitude of the current flowing in the fuse, and to the device to determine the ambient temperature of the fuse.

13. A vehicle, comprising an electrical architecture provided with the device as claimed in claim 11 .

14. The vehicle as claimed in claim 13 , wherein the vehicle is an electric or hybrid vehicle.