The General Principles and Development of Active Power Filter

With the increasing popularity of power electronic devices, they are causing more and more harm to the power grid, especially through the influence of harmonic and reactive power. Due to their inherent limitations, conventional passive filter devices cannot effectively compensate for harmonics and reactive power, which seriously affects the stability of the power system. Therefore, active filter technology has become a hot topic in the field of power electronics. It can dynamically suppress harmonics in the power grid and simultaneously compensate for reactive power. This paper briefly introduces the basic theory of active power filters, review their development process, and discusses their types and main technologies. Active power filters are expected to be increasingly used in the future to reduce the adverse effects of power electronic devices on the grid.