Systematic evaluation of hybrid active EMI filter based on equivalent circuit model

A systematic classification and identification of hybrid active EMI filter (HAEF) configurations is given: their insertion losses, impedance compatibilities, transfer functions, potential applications and their comparative features. The basis of discussion is an equivalent circuit model, which includes all possible combinations of active and passive elements and matches these to the desirable attributes. The evaluation indicates those topologies that are known and those topologies that are relatively new.