A control method of a direct current electric motor comprising a rotor and an inductor circuit (A, B) for driving the rotor, which is configured to rotate continuously and is equipped with permanent magnets, the method comprising a step of measuring (101, 111, 115), from a start time point, a time drift (Cv) in the rotor rotation by comparing a detected number of rotation cycles of the rotor with a reference number of nominal rotation cycles for the rotor corresponding to a nominal rotational speed, the nominal rotation cycles being determined by a reference clock signal; characterised in that the method comprises a step of defining (121, 125, 129, 131, 141) N speed threshold(s) with N being greater than zero, at least one of the speed threshold(s) being a variable speed threshold (dt_T1, dt_T2) depending on the measured time drift in the rotor rotation, the N speed threshold(s) defining N+1 rotational speed ranges for the rotor; the method further comprising a periodic sequence of the following steps: - measuring a time parameter (dt_Peak) of the direct current electric motor, the value of which is determined by the instantaneous rotational speed of the rotor; - adjusting the at least one variable speed threshold in function of the measured time drift for controlling an average number of rotation cycles or turns of the rotor per time unit; - based on the measured time parameter, determining (133, 137, 141) in which one of the N+1 rotational speed ranges the rotational speed of the rotor is; and - selecting (135, 139, 143) an action among a group of different defined actions relative to the control of an electrical current through the inductor circuit, based on the determined rotational speed range in the preceding step, to control the rotational speed of the rotor, wherein the group of different defined actions comprises the following actions: - applying one or more energy pulses across at least a portion of the inductor circuit; - no drive action in the current sequence; and - short-circuiting at least a portion of the inductor circuit. characterised in that the method comprises a step of defining (121, 125, 129, 131, 141) N speed threshold(s) with N being greater than zero, at least one of the speed threshold(s) being a variable speed threshold (dt_T1, dt_T2) depending on the measured time drift in the rotor rotation, the N speed threshold(s) defining N+1 rotational speed ranges for the rotor; the method further comprising a periodic sequence of the following steps: - measuring a time parameter (dt_Peak) of the direct current electric motor, the value of which is determined by the instantaneous rotational speed of the rotor; - adjusting the at least one variable speed threshold in function of the measured time drift for controlling an average number of rotation cycles or turns of the rotor per time unit; - based on the measured time parameter, determining (133, 137, 141) in which one of the N+1 rotational speed ranges the rotational speed of the rotor is; and - selecting (135, 139, 143) an action among a group of different defined actions relative to the control of an electrical current through the inductor circuit, based on the determined rotational speed range in the preceding step, to control the rotational speed of the rotor, wherein the group of different defined actions comprises the following actions: - applying one or more energy pulses across at least a portion of the inductor circuit; - no drive action in the current sequence; and - short-circuiting at least a portion of the inductor circuit. - measuring a time parameter (dt_Peak) of the direct current electric motor, the value of which is determined by the instantaneous rotational speed of the rotor; - adjusting the at least one variable speed threshold in function of the measured time drift for controlling an average number of rotation cycles or turns of the rotor per time unit; - based on the measured time parameter, determining (133, 137, 141) in which one of the N+1 rotational speed ranges the rotational speed of the rotor is; and - selecting (135, 139, 143) an action among a group of different defined actions relative to the control of an electrical current through the inductor circuit, based on the determined rotational speed range in the preceding step, to control the rotational speed of the rotor, wherein the group of different defined actions comprises the following actions: - applying one or more energy pulses across at least a portion of the inductor circuit; - no drive action in the current sequence; and - short-circuiting at least a portion of the inductor circuit.