Study On Main Circuit Of High-voltage Converter For The AC Motor Controller

The AC-motor, especially the squirrel cage AC-motor, for it's simply structure, solidity, low-cost and other characteristics, is wildly used in industry. After more than a century of development, the method of AC-motor speed control is more maturing, and the best method is Variable-frequency Regulating Speed Technology. As the development of modern industry, the way of motor is high-voltage and large-capacity, but in the filed of high voltage AC-motor speed control, most of it still adopt constant speed.Until the end of 20 century, the need of saving energy is release by the birth of high power electronic converters. The Multilevel power converter has the ability to make lower voltage semiconductors be stably used to medium-voltage and large-capacity applications while reducing the high order harmonics produced with PWM control efficiently. Now, due to expanding to medium-voltage field easily, cascaded multilevel power converters have been utilized in medium-voltage motor drives and reactive power compensations of power system.This entire subject is to research Cascaded Mutilevel High-voltage Converter applying in the filed of AC-motors speed control based on 10kV,250kW high-voltage converter. At the same time of analysing in its principle and structure, the main circuit harmonic is improved. The High-voltage converter is difficult to make into universal converter, and Virable-frequency AC motors is needed. Through the research of this new motor, we can used VVVF technology more effectively. In addition, emulational software MATLAB7.0/Simulink6.0 is used for phase-shift, multilevel and others.According to the subject, this research provides instruction for high-voltage converter structure optimization and compatible devices. Through the experiment to provide the best solution for debugging and simulation of continuous improvement.