Research On Double-fed Speed-regulating Control System Of Winding Induction Motor

Energy saving and efficiency are the main development direction of modern AC variable speed technology, energy-saving and high-performance motor drive is important for energy savings, improve product quality and productivity. By controlling the slip of the motor to achieve speed-controlling, double-fed speed-regulating control system of Winding induction motor has many advantages. It achieves the advantage of using small-capacity power converter control the speed of high-power motor to save costs, meanwhile, improves the quality in using power through regulating the motor power factor. Therefore, a further researching of double-fed speed-regulating control system for induction motor is meaningful.Firstly, the model and the principle of double-fed speed-regulating control system of induction motor is introduced. The AC-DC-AC dual PWM converter is chosen as the main circuit structure of the doubly-fed speed-regulating control system. Under this speed controlling system, the model of the induction motor on the three-phase stationary reference frame is given and simplified. And a equivalent circuits of the induction motor is proposed. Secondly, the Topology structure of rotor side converter and the Space Vector Pulse Width Modulation technology (SVPWM) is introduced. And rotor side converter control system is designed based on the basic theory of SVPWM and the rotor flux oriented control strategy. The torque and reactive power of the induction motor achieves decoupling. Under this system, the induction motor can be regulated flexibility among synchronized, sub-synchronous, super-synchronous speed operating states, adjusted, meanwhile, the power factor can be changed. Thirdly, the Topology structure and the control principle of grid side converter is introduced. The model based on switching function of grid side converter is given. Grid side converter control system is designed with using the grid voltage vector directed double-loop control strategy. Double-fed flow of slip energy and rectifier operating in unit power is achieved.At last, focusing on designing above, simulation models of doubly-fed control system is established in the Simulink, and the results of simulation prove the control system has good dynamic response and high steady state accuracy, verify the control system design is correctness and reasonableness. In addition, the hardware circuit preliminary design of doubly-fed speed-regulating control system is proposed based on TMS320F28335 of TI company, which can make a suggestion for further founding experimental platform of the double-fed speed-regulating control system.