Device for supplying power to an electrical machine of a motor vehicle

A device for supplying power to a rotary electrical machine of a motor vehicle, the device comprising:

• a first electrical energy storage unit configured to supply power to an on-board network of the motor vehicle;
• a second electrical energy storage unit configured to supply power to the rotary electrical machine;
• an amplifier supplied electrically by the first electrical energy storage unit, and which in turn supplies the second electrical energy storage unit electrically,
• wherein the amplifier comprises an oscillating circuit,
• the oscillating circuit comprising a capacitor with a value C′ and an inductive assembly comprising an inductance with a value L′ and a resistor with a value R′,
• the oscillating circuit having its own pulsation ω such that ω=1/√(L′×C′) and its own frequency f such that f=ω/(2Π), and
• wherein the value of the inductance is variable in a predetermined manner so as to increase an electric current supplied by the first electrical energy storage unit to the oscillating circuit into an amplified current supplied by the oscillating circuit to the second electrical energy storage unit.