A Speed Sensorless Control Of Induction Machine Based On Single Dc Current Sensor

This paper proposes a speed sensorless control of induction machine based on single DC current sensor. To estimate the rotor flux accurately and robustly to parameter, we adopt the adaptive full order observer with feedback matric. At the same time, to estimate the speed as quick as possible and less steady error, the paper design the adaptation mechanism based on the transfer function of the error equation. The current is vital to flux observer, and it is also the reference of the speed estimation. In order to improve the reliability of current detection and reduce the cost. we cancel the AC current sensors, replace them with a single DC current sensor to reconstruct the phase currents. However, the phase current is not always available if the voltage vector located where active voltage vector applied too short to sample the DC current sensor. We propose a method to reduce the unmeasurable area by shifting the carrier phase. the validity is verified by simulations.