Inverse decoupling control of induction motor driven by current controlled voltage source inverter

In the rotor-field-oriented frame, the current controlled voltage source inverter is used to drive an induction motor. By using high gain controller in the current inner loop, the two stator current components are regarded as the two stator reference currents approximately. Consequently, the dynamic behavior of the stator current can be ignored and the complex 4th-order induction motor model with stator voltages as control variables is simplified to 2nd-order one with stator currents as control variables. The state feedback linearization method is employed to obtain the inverse system of induction motor. It decouples the multivariable, nonlinear and strongly coupling induction motor into two independent 1st-order linear subsystems, to realize the close-loop controls of which, two integral-proportional controllers are designed. The hysteresis-band comparators are used to produce PWM signals for the current reference tracking of inverter, which realizes the fast dynamic response of driving system. Simulation results verify the effectiveness and superiority of the proposed approach.