Research On The Control Scheme Of PWM Rectifier In Asymmetry Power System

In power system, the converters produce serious harmonic, because of the extensive using of converter device. PWM rectifier is one kind. Though this kind of pollution has been controlled to a certain extent with the development of modern power electronics theory, it is still grave critical. It is urgent to solve the pollution which comes from electronic device applying three-phase PWM converter in asymmetry power system, and it becomes the researching hotspot in the field of power electronics. It is significance to research it.The thesis researches the work principle of PWM converter deeply, starts from the reason and characteristics of the asymmetry power system, use the control theory of SVPWM, basing on the PWM rectifier's commonly mathematics model, d-q model equivalent transformer modeland optimization. It illustrates the theory and structure——restraining DCvoltage harmonic using SVPWM in asymmetry power system.At last, the thesis analyzes the fundamental of SVPWM, and then chooses the kernel parameter, found simulation model using MATLAB6.5. It is true that controlling independently using double coordinate system is better in restraining DC voltage harmonic than using identical system. Thus, realizing non-convalesce error, reducing harmonic and energy loss caused by the twice harmonic in asymmetry power system, obtaining quickly following performance and high resistive performance.