The Research On Control Technology Of Hybrid Power Filter

In the current society, electric energy is gradually becoming the most closely linked with people's life. With the development of science and technology, electric motor and nonlinear power electronic devices have been widely used. These appliances not only consume active power, but also generate reactive power and a large number of harmonic current. This will not only increase the burden on the grid will also cause a threat to other electricity equipment.Hybrid active power filter has absorbed the active power filter and the traditional passive filter,it can better eliminate reactive power and suppress harmonics. Hybrid active power filter will become the development trend of the future filter device.In this paper, the fundamental principle of hybrid active power filter is studied firstly,including the principle of active power filter, the principle and parameter design of single tuned filter, principle of thyristor controlled reactor and thyristor switched capacitor.The topology of hybrid active power filter is studied and the characteristics of various structures are studied.Then the core problem of hybrid active power filter is studied, which is the detection of harmonic and reactive current. I_p and i_q harmonic detection algorithm based on instantaneous reactive power theory is studied. The reactive power compensation method for the system is studied by means of calculating compensation. The compensation susceptance calculation formulas were deduced and the calculation method of the positive sequence current, negative sequence current.Then, the DC voltage control of active power filter is studied. The traditional PI control mode is analyzed. A new type of PI control mode is proposed, which is based on the traditional PI control mode.Finally, the hybrid active power filter system is designed. Including the design of the main circuit topology, the selection of the active part of the switch tube, the design of the active part output filter, the design of various control circuits and the design of related software. The simulation and experimental verification of the whole system are carried out.