Research On One-cycle Control Active Power Filters

The harmonic caused by a lot of electronic equipment was studied, particularly the power inverter and identifies solutions in the paper. A great amount of power harmonic is produced along with the development of power electronics and the wide application of power electronics equipments. Much attention had paid to correct power harmonic all over the world. Active power filter (APF) is regarded as an effective way to correct power harmonic.One cycle control theory developed since 1990s is a large signal and nonlinear technology, which features the goodness of simple circuit structure, high control precision, and fast response velocity, and has been applied in many fields. The research and the experiment on the one cycle-control in the active filter's application conducted. New development of one-cycle control is survey, which includes the feasibility, modeling, steady state and dynamic study as well as some improvement in one-cycle control. And analyses the various control methods of the active power filter based on OCC theory, and its advantages and disadvantages compared.Except giving OCC equation through mathematic deduction, the paper also explains the theory of OCC APF in running principle. The important signal Vm can be calculated based on the relationship between those voltages and currents signal and their change. At the same time, the parameters choice principle of PI controller is introduced. The principle can give the guidance for parameters calculating. And through simulation of OCC APF by PSIM7.0, the validity of the OCC theory is proved.And then compared the three bridge arm APF and the four bridge arm APF of three-phase four-wire system, derived the Equations of three-phase four-wire control system with four bridge arm APF. Based on OCC equation, hardware circuit is designed which can control main topology running for harmonic suppression and reactive power compensation. Finally through simulation of OCC APF for the power inverter which is most widely used in power electronics by MATLAB7.1, the correctness and feasibility of the control method is proved.At last, author verifies the OCC theory analysis and simulation result through three phase OCC APF experimentation, the analysis and result of the experiment whitch can prove that OCC theory is correct and feasible.