Built-in common-mode electric reactor of three-phase electric reactor

The invention relates to a built-in common-mode electric reactor of a three-phase electric reactor, and aims to provide the built-in common-mode electric reactor of the three-phase electric reactor used for two groups of three-phase inversion output side filtering circuits in a parallel operation for filtering difference mode harmonics as well as common-mode harmonics. The built-in common-mode electric reactor of the three-phase electric reactor comprises six iron core columns, five upper iron yokes, and five lower iron yokes, wherein each iron core column is wound by a coil separately; an air gap is formed in each iron core column; the six iron core columns are divided into two groups by taking three iron core columns as one group; one iron core column group is arranged between one upper iron yoke and one lower iron yoke in parallel while the other iron core column group is arranged between another upper iron yoke and another lower iron yoke in parallel; the last three upper iron yokes are arranged above the