Analysis And Design Of Three Phase Shunt Active Filter

The wide use of power electronic equipment makes harmonic problem deteriorated increasingly. Harmonic becomes the primary factor influencing power quality. As an effective means of harmonic restraint, active power filtering (APF) technique becomes the research focus of scientific and technological personnel. The ordinary countermeasure is to compensate the respective load attribute on the spot of the loads, but it is hard to avoid attending one thing and losing sight of another, when the compensation is not made by unitizing math mode. Now the use of active power filter is an important trend for harmonic restraint and reactive power compensation. The countermeasure we adopt is to regard harmonic, reactive power and negative power as a kind of distorted wave, so we can compensate together. Our work is adopting some algorithm to integrate the distorted wave in the load current and controlling the compensation equipment according to some control technique, so that the compensation equipment can produce the distorted wave and achieve the compensation purpose. The paper summarizes APF respectively from topological configuration of main circuit, detection arithmetic of compensation component and control strategy. It introduces the detecting method of compensation component based on Park transformation theory in detail. The paper builds an integrated simulation model including respective subsystems for three phase shunt power active harmonic compensation system based on SIMULINK function of MATLAB. The simulation result is correct, proves the validity of the detecting method and can reflect dynamic change. A control system of active power filter based on Digital Signal Processor is presented, and also the configuration and function of the control system is introduced. When we detect the current distortion, LPF influences the systemic feature of the shunt-APF. In this paper, the main design idea about LPF is according to the principle of IIR low pass filter approach. The correctness and effectiveness of the method are verified experimentally.