Method for controlling the primary ignition current of an internal combustion engine with controlled ignition

A method for controlling a primary current in an ignition coil of an internal combustion engine with controlled ignition, in which the current is established in an inductive primary circuit over a given duration, referred to as the conduction time and determined by calculation and/or as a function of measurements carried out in the primary circuit,

• characterized in that the conduction time is calculated according to the following steps:
• predetermining the predetermined conduction time (tdi),
• carrying out at least one measurement of the current (Ici) in the primary circuit at an instant (ti) lying in the last tenth of the predetermined conduction time (tdi) but before the end of the predetermined conduction time,
• estimating the current (Ifi) only at the end of the predetermined conduction time (tdi), as a function of the measurement or measurements carried out during said last tenth,
• optimally correcting the conduction time (tdi) for the ignition cycle during which the last current measurement was carried out, as a function of the previous estimate and the current (Itarget i) desired at the end of the conduction time.