Research On Control Strategy Of Series Hybrid Active Power Filter

Hybrid active power filter is one of the important research directions in active power filter. This paper analysis and researches the hybrid series active power filter on LC resonance in-depth.This paper discusses the importance of power quality and introduces the harm of harmonic, the traditional methods of harmonic suppression and the advantages of active power filter. The research purposes of this paper are proposed based on the domestic and foreign present situation and the technical progress of harmonic suppression. Firstly, the working principle and filter characteristics of the hybrid series active power filter have made a detail research. The simulation results show that the filter characteristics of the hybrid series active power filter have been great improved compared with the traditional method.Stability is the prerequisite of the system normal operation. From the start, the network inductance, system time delay and passive power filter parameters are analyzed making use of Routh criterion. The analysis shows that:the larger the network inductance is and the smaller the time delay is, the larger the K will be and the better the harmonic suppression performance will be. In order to improve the stability of the system, the PD compensation is connected in the main circuits. Analysis results show that:stability margin increases and harmonic compensation characteristics are improved.The DC-link voltage affects the filter performance, thus the paper introduces the fuzzy control theory and applies the theory to the control of DC-link voltage. The combine of PI controller and the fuzzy controller solves the static and dynamic performance of the DC-link voltage. By Matlab software, the DC-link voltage control effect is analyzed. The simulation results show the effectiveness of the fuzzy PI control.