Electronically commutated motor, esp. for driving a fan with variable revolution rate,

摘要

The motor (11) has at least one winding (12,13) with its current controlled by a semiconducting control element (30,38) with a control electrode and an output electrode, between which is connected a series circuit containing a capacitor (42,45) and a resistor (43,46). The control device (70), dependent on a motor operating parameter, influences charging or discharging of the capacitor depending on temperature and/or revolution rate to control the gradient of the switch-off edges of the current pulses flowing in the winding so that it increases with increasing temperature and/or revolution rate. The control device is connected to the capacitor via a diode (53,54).