The Research On High Speed Control Schemes For Induction Motors

With the rapid development of technology, high-performance CNC machine is a keyto enhance China’s machinery and equipment manufacturing industry. The high-speedspindle drive system of induction motor is an important part of CNC machine. The thesismainly studies the high-speed induction motor control strategy and identification of therotor time constant.Indirect field oriented technology (IFOC) is used as the basic control scheme of thesystem. PI controller with decoupling is used as current loop controller and the voltageoutput uses space vector pulse width modulation technique. Deriving the ideal current andvoltage vector trajectory and combing with conventional field-weakening method, anoptimized voltage closed-loop field-weakening allocation strategy is presented. Then theimpact of excitation current, the torque current, the magnetic field orientation angle andthe electromagnetic torque output as well as torque model, model of voltage, active andreactive model of model reference adaptive system (MRAS) method parameter sensitivityare analyzed. The reactive power model has the smallest sensitivities and an identificationmethod based on the excitation reactive power model is proposed. The model of reactivepower can reduce the load current of the motor condition to improve the robustness of theidentifications. Finally, the experiment platform is built and the experimental results verifyprevious theoretical analysis and programs. And the work is summarized and the prospectis put forward.