An active filter is coupled to a dc line of a converter such as a dc-dc converter. The active filter traps a harmonic frequency component of chopped current on the dc line. A passive EMI filter may also be coupled to the dc line to remove higher harmonic frequency components of the chopped current on...http://www.google.fr/patents/US6414866?utm_source=gb-gplus-shareBrevet US6414866 - Active filter for a converter having a DC line
