Induction motor sensorless vector control with an adaptive speed observer and direct electrical angle correction in coordinate transformations

The article describes the method for implementation of the induction motor sensorless control system based on the adaptive rotor speed observer with continuous angle correction in coordinate transformation based on a phase-locked loop. The method is chosen because of a simpler model implementation to real object adjustment. It is a very convenient method for educational purposes to be included in the Masters and Bachelors programs. The analysis of the control system simulation results using speed estimation without angular correction block showed poor control quality due to the angular error accumulation in the velocity integration process. At the same time, the transition processes were followed by undesirable nonlinear distortions. The speed observer implementation uses the original method of correction at angular error calculations on the basis of phase mismatch determination of the stator current measured and reference vector. The control system quality was proven by simulation tests of the control system model in the Mexbios Development Studio environment. The model simulation results confirm efficiency of the proposed methods which are used by the induction motor sensorless vector control.