Adaptive Modulation Frequency Selection System in Power Active Filter

The article presents a system of automatic control of the power active filter with an adaptive structure for selecting the frequency of power switches. Determination of the switching frequency is based on the frequency spectrum of the load current, the value of the cutoff frequency of the transistors and the magnitude of power losses in the power switches. The proposed control system, depending on the harmonic composition of the load current, allows to reduce the modulation frequency and, thus, to reduce its own power losses in the active power filter.