The Development Of New Hybrid Active Power Filter Based On Dsp Srthaf

The harmonic of power system has brought great harm to social production and the life of people. In recent years, more and more serious harmonic pollution has aroused the extensive attention of all society, and various devices of harmonic elimination also emerge as the times require. In order to meet the needs of society and combining the actual condition of factory, this dissertation develops a novelSeries Resonant Type Hybrid Active Filter--SRTHAF, which is mainly used toeliminate the harmonic in metallurgical works. The research of SRTHAF will also build solid base for its universal application in our country, and accumulate experiences for its high-voltage and high-power application.This dissertation firstly discusses the causation and harm of harmonic, and analyses the present research situation, classification and basic working principle of APF. Based on these, SRTHAF is proposed. SRTHAF combines APF(Active Power Filter) and PF(Passive Filter), and has the advantages of injection type APF. Therefore, SRTHAF is a novel harmonic elimination scheme which has large capacity and low cost. Through analyzing SRTHAF circuit structure, the switch-function model of SRTHAF is established, which can be used to study its control strategy.Through the compare of the existing harmonic detection methods, the ip,iq algorithm based on the instantaneous power theory is introduced briefly. Traditional ip,iq algorithm will be improved by adopting DSP. It will have more rapid handling speed and more strong detection performance.Deep research on the control strategy of APF is made in this dissertation. The traditional control methods (such as proportional-integral control, sliding-mode control, synchronous revolving PI control, and so on) can not meet all the demands of algorithm, real time, speed, robustness and control precision. Therefore, fuzzy PI intelligent control method is proposed which realizes the combination of fuzzy control and traditional PI control. Fuzzy PI control strategy makes SRTHAF have fast dynamic respond speed and stable harmonic eliminating effect, and further improves the control property of APF.Finally, the device of SRTHAF based on DSP is established according to the actual harmonic and reactive power compensation demand of metallurgical works. The dissertation explains the circuit design, components selection and software flowchart in detail. The result of calculation and experiment analysis shows that the device has very good harmonic and reactive power compensation function. SRTHAF has large capacity and low cost, which suits-metallurgical enterprise very much.