Research On The Optimization Of Series Hybrid Active Power Filter

It has been a more and more important research project to suppress the power systemsharmonics. And the applying of Active Power Filter(APF) will be the main solution. Toprovide the theoretical feasibility of harmonic suppression in high voltage level, SeriesHybrid Active Power Filter based on Fundamental Magnetic Flux Compensation ispresented. In order to ensure series hybrid active power filter (SHAPF) to operate normallyin a better filtering effect, and to reduce the disturbance variable between the inverters, asingle-phase SHAPF is presented in this paper. It separates the three-phase inverter which isconnected to the secondary of the transformers into three sets of single-phase bridgeinverters. So the currents are completely decoupled. And the next, detailed introduction ofthe principle of control strategy and the simulation research is given. Based on above, aprototype is constructed. The contrast tests show that it has a better filtering effect.Otherwise, as the series transformers are under harmonic voltage which causes distortion inthe output of inverters, so the filtering effect will be affected somehow. It has beenintroduced in this paper to raise the DC voltage of the inverters to induce the proportion ofthe harmonic voltage. And test shows that it is feasible. In the last, a SVPWM controlstrategy is presented. This strategy has advantage of higher voltage utilization, lessharmonic content and fewer switching loss. Therefore, the control strategy of SVPWM withseven segments is introduced. And a program is built in S-Function to realize it. Thismodule is applied to the simulation of the SHAPF. As the simulation results show, it has agood filtering effect and stability.