Electrical filter for reducing sub-harmonics or intermediate harmonics

摘要

The filter has at least one parallel circuit with an ohmic damping resistance (R1,R3,R3') and a filter choke (L1,L3) in series with a filter capacitor (C1,C31,C31'). The resistance value of the damping resistance ensures a current amplification by the filter of between 3 and 5 times at its lowest frequency pole, which is a whole multiple of the supply network frequency (fN).