Research And Application Of Controller In Active Power Filter

APF (Active Power Filer) has been extensively applied in harmonic eliminating of power network. Taking the harmonic elimination of a Copper Foil Company as object of study, the thesis is focused on the application of HAPF (Hybrid Active Power Filter) and expands the hardware design of controller, harmonic detection methods and software design of controller, as well as parameter design. The research of HAPF will also build solid base for its universal application in our country, and accumulate experience for its high-voltage and high-power application.The hardware structure of APF controller based on DSP (Digital Signal processor) has been presented, referring to the research achievement inland and aboard. The real-time performance and reliability, as well as compatibility of controller have been analyzed in detail. In order to meet the requirement of dead-time that IPM (Intelligence power module) demands, independent hardware circuit for generating dead-time is designed in this thesis.Harmonic detection is a very important part of APF. Control strategy and performance of APF will be greatly influenced by calculation delay and low-pass filter in many harmonic detection methods. Then an algorithm based on a simplified sliding-window Fourier is presented in this thesis, which makes calculation of harmonic current in APF simply and detects referenced current effectively. And then, the effectivity and feasibility of this algorithm have been proved in the theory of frequency-domain filter.The software design of controller is divided into menu program and control program. The menu program is composed of the display about real-time voltage wave, current wave, spectrum and control variable; the control program includes the sampling and signal analysis, the modulation and triggering of signal and the modification of control variable. At last, the thought and realization of system program are formulated in this thesis.With the appliance of HAPF in Jiang Xi Copper Foil Company, the system topology structure, main circuit design, parameters computation and output filter design are discussed. Furthermore, the feasibility of this equipment has been validated by applying effectiveness.