Method for controlling an at least two-phase brushless motor (M), preferably without a rotor position sensor, comprising at least the steps of: • determining a target phase voltage (U MotorRef ) based on one of ∘ a predetermined target power and an actual power, ∘ a predetermined target speed and an actual speed, ∘ a target current and an actual current, • energising the two phases (U, V, 1N) with a phase voltage (U Phase ) based on the target phase voltage (U MotorRef ) and a detected actual phase voltage, the phase voltage (U Phase ) of the energisation being adjusted by means of PWM control, • comparing the determined target phase voltage (U MotorRef ) with a detected intermediate circuit voltage (U DC ), characterized in that • in response to the comparison , in the case that the determined target phase voltage (U MotorRef ) corresponds to the detected intermediate circuit voltage (U Dc ) minus an optional offset: o identifying an induced voltage {ΔU} of a non-energised phase (U, V, W), o determining a target value of the induced voltage (ΔU ref ) based on the predetermined target power (P ref ) and the actual power (P act ), o comparing the identified induced voltage (ΔU) with the determined target value of the induced voltage (ΔU ref ) and o adjusting the PWM frequency if the difference between the identified induced voltage (ΔU) and the determined target value of the induced voltage (ΔU ref ) is not equal to zero. • determining a target phase voltage (U MotorRef ) based on one of ∘ a predetermined target power and an actual power, ∘ a predetermined target speed and an actual speed, ∘ a target current and an actual current, ∘ a predetermined target power and an actual power, ∘ a predetermined target speed and an actual speed, ∘ a target current and an actual current, • energising the two phases (U, V, 1N) with a phase voltage (U Phase ) based on the target phase voltage (U MotorRef ) and a detected actual phase voltage, the phase voltage (U Phase ) of the energisation being adjusted by means of PWM control, • comparing the determined target phase voltage (U MotorRef ) with a detected intermediate circuit voltage (U DC ), characterized in that • in response to the comparison , in the case that the determined target phase voltage (U MotorRef ) corresponds to the detected intermediate circuit voltage (U Dc ) minus an optional offset: o identifying an induced voltage {ΔU} of a non-energised phase (U, V, W), o determining a target value of the induced voltage (ΔU ref ) based on the predetermined target power (P ref ) and the actual power (P act ), o comparing the identified induced voltage (ΔU) with the determined target value of the induced voltage (ΔU ref ) and o adjusting the PWM frequency if the difference between the identified induced voltage (ΔU) and the determined target value of the induced voltage (ΔU ref ) is not equal to zero. o identifying an induced voltage {ΔU} of a non-energised phase (U, V, W), o determining a target value of the induced voltage (ΔU ref ) based on the predetermined target power (P ref ) and the actual power (P act ), o comparing the identified induced voltage (ΔU) with the determined target value of the induced voltage (ΔU ref ) and o adjusting the PWM frequency if the difference between the identified induced voltage (ΔU) and the determined target value of the induced voltage (ΔU ref ) is not equal to zero. <EOS>