Method and apparatus for determining the AC component of a current produced by the mechanical commutation of a DC motor

摘要

The method involves measuring the current and estimating a periodic component of the current. The estimation is aided by an observing device (2) with a mathematical model (30) of the direct current motor (6). A determination is made for the change portion from a difference from the estimated periodic component and the measured current. By evaluating a difference signal from the estimated periodic component and the measured current an engine angle of rotation is determined. A feedback of a difference from an estimated and a measured parameter in the model of the direct current motor is accomplished and weighted. An independent claim is included for an AC component determining apparatus.