Design and evaluation of a novel AC line filter “Pentaleads ® ” having quasi-distributed constant structure

A novel common-mode AC line filter “Pentaleads ® ” having five leads including an extra lead for grounding was developed. In order to realize an effective insertion loss in wide frequency range without using Y-capacitors, simple and unique quasi-distributed constant structure was adopted. The novel filter shows broad-band attenuation characteristics beyond 10MHz which is nearly equal to a filter circuit consisted of a conventional line filter with Y capacitors of 3300pF. The novel filter enables not only realizing its attenuation characteristics broad, but also extremely low leakage current which is approximately only 1/20 of that of an equivalent LC structured filter.