Shaver motor speed control

A drive control for driving a dc motor of an electrical household appliance, in particular a hair cutting device such as an electric razor, shaver or epilator, at constant rotational speed, the drive control comprising:

• a detection means for determining a parameter indicative of the actual rotational speed of the dc motor,
• a closed loop control for adjusting a supply voltage (Um) to the dc motor based on a control deviation between a target value and the actual value of the parameter indicative of the rotational speed of the dc motor, wherein the closed loop control has
• a fast control and a slow control for adjusting the supply voltage with the fast control providing a faster correction of the control deviation than the slow control, and
• a processor means for determining a switching criterion for switching between the fast control and the slow control,
• wherein at least one first switching criterion from the slow control to the fast control and at least one second switching criterion, different from the at least one first switching criterion, from the fast control to the slow control are provided, and wherein the close loop control is adapted for switching from the fast control to the slow control, and from the slow control to the fast control, based on the first and second switching criteria.