The invention discloses an integrated structure of an
inducer and a
capacitor in an EMI wave filter realized through a flexible circuit board, the integrated structure comprises a three
magnetic core column closed
magnetic circuit. An air gap is arranged on the middle
magnetic core column of the closed
magnetic circuit, a cylindrical dual-surface flexible circuit board is respectively wound on two side
magnetic core columns and is composed of a first insulating layer, a first
copper foil, an isolation medium layer, a second
copper foil, and a second insulating layer which are overlapped. The first
copper foil, the isolation medium layer and the second
copper foil of the cylindrical dual-surface flexible circuit board form a common mode
capacitor in the EMI wave filter, two cylindrical dual-surface flexible circuit boards form a common mode
inductor in the EMI wave filter through a
coupling inductor formed by the side magnetic core columns, two cylindrical dual-surface flexible circuit boards form a difference mode
inductor in the EMI wave filter respectively through a
magnetic circuit composed of the side magnetic core columns and the middle magnetic core column. The integrated structure of the
inducer and the
capacitor provided by the invention is favorable for decreasing the volume of the EMI wave filter, and improving the
power intensity of a power electronic convertor.