| As a non-linear and multi-coupled system, the control of the AC induction motor (ACIM) has long been challenging. Thanks to the vector control algorithm, ACIM can offer the same control capabilities and dynamic performance as traditional high-performance DC motors. With the vector control algorithm, the stator current of ACIM can be expressed in two orthogonal axes, and thus the rotor flux part and torque are de-coupled. In this paper, a design of closed-loop rotor flux oriented vector-control system of induction motor is presented based on 56F8346 from Motorola.In this paper, the theory of vector-control and corresponding mathematical model are addressed in great details. The strategy of rotor-flux-oriented vector control for ACIM is given. The design of speed-, flux-, and current-closed-loop controllers is described. To address the problem that the rotor flux depends heavily on motor parameters, an updated model is presented by combining the strengths of both voltage model and current model. With the updated model, the rotor flux estimation accuracy and robustness to motor parameters are also improved. The operating principles of SVPWM and associated control algorithms are also covered in the paper. By using SVPWM to control the magnitude and phase angles of the spatial voltage vector, the speed control of the drive system in this paper can reduce the output of current harmonics, lower the torque ripple, and improve the energy efficiency.In order to improve the PFC (Power Factor Correction), a boost-APFC-based power driver for the vector-control ACIM is designed in this paper. Based on the state space equations of ACIM, a simulation model of the control system of ACIM is designed by using Matlab/Simulink. The results of experimentation and simulation indicate that the method of rotor flux oriented vector-control for AC the induction motor is of good dynamic and stability performance. At the end of paper, the conclusion and further research expectation are presented.
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