Kollektorloser Gleichstrommotor

摘要

The d.c. motor has stator coils (L1-L4) to which commutation signals are successively applied via switches (S1-S4). The commutation signals are generated by a PLL circuit (17) which receives a pulsed signal (U4) depending on the rotor frequency which is taken from a stator coil (L1). The PLL circuit (17) generates an output voltage (U5), the frequency of which corresponds to a whole multiple of the rotor frequency. This signal is taken to a counter (35), the status of which is decoded by a decoder (36). The commutation signals are thereby successively generated, their frequency and phase being automatically matched to the current rotor frequency.