Solving a Dead-lock Problem of NFO Sinus

Abstract: This thesis presents, analyzes and suggests solutions to the dead-lock problem of the sensorless variable speed drive NFO Sinus. Friction, measurement, parameter estimation and quantization effects are believed possible origins of this problem and is hence studied. A short introduction to ¯eld oriented control of the asynchronous AC motor and the NFO Control strategy is also included. The report is published at LiTH as ISRN LiTH-ISY-EX--06/3945--SE and at LTH under ISRN LUTFD2/TFRT--5780--SE.