With the developments of the AC-drive techniques and their widely industrial and agricultural applications, many researchers paid their attentions to the high performance control of the induction motor. In this thesis, our research focuses on the high performance induction motor drive system, which is based on the vector control techniques. Three aspects, parameter identification, rotor flux observer and close-loop controller design, are deeply studied theoretically. In addition, a vector control platform based on rotor-field-oriented is also developed and the corresponding simulation and experiment results are provided. 1. We introduce the developments of the vector control of induction motor.The contents involve motor parameter identification, rotor flux observer, high performance controller and speed estimation.And their developing trends are also detailed discussed. 2. The state space equations of induction motor are systemically summarized and the principles of the rotor-field-oriented vector control are evaluated in this section. 3. We propose a novel method for the off-line identification of motor parameters. In our method, by injecting DC or single phase AC excitation signals, we estimate the motor parameters based on the stable mathematical model and the obtained data. In addition, we also give an identification error analysis and compensation from three aspects, dead time, diode voltage drop and phase lagging. 4. To solve the problems of errors in magnitude and phase angle using low-pass filter, we propose an rotor flux estimation method based on the improved stator voltage model. Because the variations of rotor resistance and speed can also degrade the accuracy of rotor flux observer, a novel rotor flux observer based on the close loop Extended State Observer method is proposed, which compensates the observing value of rotor flux into the known models and composes a close-loop rotor flux observer with strong robustness. 5. Based on the model of induction motor in field-oriented coordinates, we design the controller for speed and rotor flux using an adaptive backstepping method, in which we define the suitable Lyapunov functions to guarantee the stability of the system and obtain the final control law and parameter updating law. The proposed approach can asymptotically track the rotor speed and flux reference signals under parameter uncertainties and load torque disturbance. 6. An experimental platform of the vector control induction motor drives is designed and built, based on which the primary experiments are developed.
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