Method for the contactless charging of the battery of an electric automobile

A system for contactless charging by magnetic induction of a battery of an electric automotive vehicle comprising a receiving resonant circuit which includes a receiving coil, the system comprising:

• an emitting resonant circuit comprising an emitting coil;
• an inverter across terminals of which is linked the emitting coil;
• an analog and digital motherboard on which are disposed an analog circuit and a control board, a current and a voltage across the terminals of the emitting coil being measured and processed by the analog circuit that computes an absolute value of a phase shift between the current and the voltage, a phase shift signal arising from the analog circuit being injected as an input into the control board which emits as an output setpoints to the inverter;
• and
• an analog-digital converter for converting the phase shift into a numerical value,
• the control board being configured to slave a frequency of the setpoints dispatched to the inverter to a value of the phase shift, for magnetic coupling between the emitting coil and the receiving coil when the vehicle is positioned above the emitting coil,
• wherein the slaving is implemented by a proportional integral regulator, a value of a proportional gain of the proportional integral regulator and a value of an integral gain of the proportional integral regulator optimize a rate of convergence of the frequency of the inverter to the predetermined value.