Patent ID: 8625245

Claim:
A method for protecting an electronic switch ( 4 ) incorporated in an automotive vehicle comprising a power supply battery ( 3 ), in order to control the power supply of an electric load ( 2 ) having a startup period before reaching a steady operating state, said protection method consisting: in the steady state of the electric load ( 2 ), in implementing a protection strategy based on the use of a table of so-called overload intensity values IS such that each value of IS=IT+ΔI, with IT being the theoretical intensity of the current flowing through the electronic switch ( 4 ) for a given value of the voltage at the terminals of the power supply battery ( 3 ), and ΔI being a predetermined value representative of an electric overload, said protection strategy consisting: in regularly measuring the value of the voltage at the terminals of the power supply battery ( 3 ) and a value representative of the current IL flowing through the electronic switch ( 4 ), and in comparing each measured intensity value IL with the value IS corresponding to the same voltage of the table of overload intensities, and in counting the overshoots of the overload values IS so as to interrupt the operation of the electronic switch ( 4 ) when the number of overloads undergone reaches a predetermined value, and, during each startup period of the electric load ( 2 ), in inhibiting the protection strategy for a predetermined time period according to the electric characteristics of said electric load, said protection method being characterized in that a table of overload intensity values IS is established showing: for values of the voltage at the terminals of the power supply battery ( 3 ) that are greater than a predetermined voltage value VNbat, values IS=IT+ΔIc, with ΔIc being identical for all said values, and, for values of the voltage at the terminals of the power supply battery ( 3 ) that are less than or equal to VNbat, a constant value IS such that IS=IT(VNbat)+ΔIc, with IT(VNbat) being the theoretical intensity of the current for the voltage VNbat.