current controlled harmonic filter with intelligent adaptation
SOFIA® raises the bar in voltage controlled harmonic filtering. With a rising number of controlled loads, such as frequency converters or switch-mode power supplies, the number of loads with non-linear U-I-characteristic rises. This affects the electrical power supply grids in a way, as if they are a current source, which injects integer multiples of the fundamental current. These currents are named harmonics.
In the first instance harmonic currents stress the grid above the technically necessary level thus, that circuit breakers, transformers, transmission lines and o on must carry higher currents. Secondary the harmonic currents cause a distortion of the grid voltage. These currents with higher frequency feed against the grid impedance and thus cause distortion of the grid voltage. Furthermore resonances and effects from switching mode frequencies cause a deviation from the ideal voltage waveform.