摘要 |
Electrical direct current actuators, which have a distinct low-pass behavior with respect to the actuating signal, are frequently used in electronic control and regulation devices. Typical examples of such actuators are d.c. motors or electromagnets. In order to minimize the power losses when controlling such electric d.c. actuators, the associated power amplifiers usually are controlled by a pulse-width modulated actuating signal in the kHz frequency. In order to ensure that the actuator also is activated with the predefined actuating signal when there are variations in the supply direct voltage, the calculated actuating signal is multiplied by a scaling factor in a first functional module, with this scaling factor being obtained in another functional module on the basis of the relationship between the actual supply voltage and the nominal supply voltage. This rescaled actuating signal is then fed to the pulse-width modulator instead of the output actuating voltage causing the pulse duty factor to be adapted to the actual supply voltage. |