A method of assembling an inverter structure (1) includes: winding a coil set (12) around a bobbin (11), the bobbin (11) including a first side (11a) and a second side (11b) opposite to each other; inserting a first core pillar (21) of a first iron core (20) into a through hole (110) of the bobbin (11); sequentially placing a first insulation body (30), a middle iron core (40) and a second insulation body (50) into the through hole (110) from a second side (11b) of the bobbin (11); and inserting a second core pillar (61) of a second iron core (60) into the through hole (110) from the second side (11b) of the bobbin (11) and arranging the second core pillar (61) to be in contact with the second insulation body (50).