Alternating current (AC) electrical drive control without mechanical sensors
is an active research topic. This paper studies the observability of both
induction machine and synchronous machine sensorless drives. Observer-based
sensorless techniques are known for their deteriorated performance in some
operating conditions. An observability analysis of the machines helps
understanding (and improving) the observer's behavior in the aforementioned
conditions.Comment: arXiv admin note: text overlap with arXiv:1512.0366