The invention relates to a method of controlling a permanent-magnet synchronous machine (3) comprising a stator and a rotor. The method comprises a step of determining an estimated position ($) of the rotor, a step of determining a second direct voltage setpoint (νδ2*) which is alternately equal to a first direct voltage setpoint (νδ1*) or equal to the first direct voltage setpoint (νδ1*) plus a predetermined periodic signal (G). The step of determining an estimated position ($) of the rotor comprises a step of determining a coupling term (Δϊγ), a step of determining a speed of rotation of the rotor (Ω5) as a function of said coupling term (Δϊγ), and a step of determining the estimated position ($) of the rotor by integrating the speed of rotation of the rotor (Ω5).