Patent ID: 6163117
Filing Date: 2000-12-19
Classification: H02P

Abstract:
A method of operating an electronically commutated motor having at least three stator winding strands and a rotor which, to detect an instantaneous position of said rotor, has a number of signal-producing rotor position sensors which is smaller, by at least one, than a number of rotor position sensors intrinsically necessary for this number of strands in order to control commutation of said motor, having the following steps:(a) deriving within each range of rotor positions in which an adequate association between sensor output signals and rotor position is possible, a virtual rotor position signal (H3B') from the output signals of said rotor position sensors, as a substitute for the output signal of a sensor which is not present; and(b) using, within each range of rotor positions in which an adequate association is not possible, an estimated value for the virtual rotor position signal, which value is a function of an output signal (H1) of at least one of the existing rotor position sensors.