Research On Three-Level Inverter SVPWM Modulation And Asynchronous Motor Vector Control System Of Intelligent

With the rapid development of power electronic technology and microprocessor technology,AC speed regulating system has achieved significant results,but the application of AC speed regulating system in the field of high pressure and high power is still limited by the voltage grade and current capacity of power electronics device.With the proposed of multilevel topological structure in the power electronic technology,effective to solve the technical bottleneck of the high pressure high power speed regulation system, and diode clamped three-level topology has been widely used. This thesis researches on the vector control system based on this topological structure.Firstly, the thesis introduces the diode clamped three-level topology and the principle of SVPWM,and based on the theory of60degree coordinate.simplified the algorithm of three level SVPWM,modeling and simulating to the modifiled three level SVPWM algorithm in Matlab/Simulink simulation platform,the simulation results show that the algorithm is correct. Then based on the mathematical model of asynchronous motor in the three-phase static coordinate,through the coordinate transformation,getting the mathematical model of induction motor in two-phase static coordinate and two-phase rotating coordinate. Secondly,it discusses the basic concept of induction motor vector control and the basic principle of rotor field-oriented, given the speed and magnetic chain double closed loop vector control system scheme,designed the speed fuzzy PI controller and voltage feedforward decoupling controller,through Matlab/Simulink modeling and simulation,confirm that the control system has good dynamic performance,steady precision.At last, it introduces the hardware circuit design of the three-level inverter control system based on TMS320F28335and implements the improved three-level SVPWM algorithm based on the three-level inverter experimental platform; and the result of the experiment proves the improved three-level SVPWM algorithm is correct. It also does some research on vector control system of three-level inverter and the result of the experiments proves that the control system achieves the purpose of decouple control on the flux and torque of the induction motor, and has a quick dynamic response.