Electrical power supply system for a vehicle

1 . A method for managing the use of an on-board motor vehicle battery charger, the vehicle comprising a supply battery, the on-board charger being connected, on the one hand, to said battery and being intended to be connected, on the other hand, to an electrical power supply network that is external to the vehicle and is able to provide a three-phase voltage, each network phase is characterized by a maximum overall usage power, the on-board charger comprises a plurality of conversion modules, each conversion module comprises a plurality of elementary power conversion units that are independent of one another, each elementary unit being characterized by a maximum usage power threshold, each conversion module being intended to be connected to an external power supply network phase, the method comprising:

a) determining the electrical energy that has passed through each elementary unit since the start of the use of said elementary unit,

b) determining the activation order of the elementary units by ordering the different elementary units from the one having had the least amount of electrical energy passed through it to the one having had the most electrical energy passed through it,

c) determining the power value to be provided by each conversion module on the basis of the voltage that each electrical power supply network phase is able to provide and the maximum overall usage power of each network phase,

d) allocating a maximum power value to each elementary unit from the previously determined list on the basis of:

i) the determined activation order,

ii) the maximum usage power threshold of each elementary unit

iii) the maximum overall usage power of each network phase,

e) determining the instantaneous overall power that the on-board charger has to provide,

f) activating the elementary units on the basis of:

i) the power allocated to each elementary unit,

ii) the instantaneous overall power that the on-board charger has to provide.

2 . The method as claimed in claim 1 , wherein, during the allocation step, the power allocated to each elementary unit is defined as follows: for each elementary unit and following the activation order of the elementary units, the allocated power is:

a) equal to the difference between the maximum overall usage power of the phase connected to said conversion module and the value of the sum of the powers allocated to the other elementary units of the same conversion module,

b) and defined so as to be less than or equal to the maximum usage power threshold.

3 . The method as claimed in claim 2 , wherein, during the activation step, the elementary units to be activated are chosen by selecting, following the activation order, the minimum number of elementary units for which the sum of the maximum allocated powers is greater than or equal to the instantaneous power.

4 . A power supply system for a motor vehicle, comprising:

a) a supply battery,

b) an on-board charger being connected, on the one hand, to said battery and being intended to be connected, on the other hand, to an electrical power supply network that is external to the vehicle and is able to provide a three-phase voltage, each network phase is characterized by a maximum overall usage power, the on-board charger comprises a plurality of conversion modules, each conversion module comprises a plurality of elementary power conversion units that are independent of one another, each elementary unit being characterized by a maximum usage power threshold, each conversion module being intended to be connected to an external power supply network phase,

c) a control unit able to implement the method as claimed in claim 1 .

5 . A motor vehicle comprising a power supply system as claimed in claim 4 .