Reactor

A reactor comprising:

• an outer peripheral iron core;
• at least three core coils contacting or connected to an inner surface of the outer peripheral iron core;
• each of the core coils including a core and a coil wound onto the core;
• and
• an attachment unit disposed on one end surface of the outer peripheral iron core, for attaching the outer peripheral iron core in a predetermined position, the attachment unit including an end plate and a plurality of extension portions cantilevered to the end plate, each of the plurality of extension portions having a respective base abutting the end plate, the plurality of extension portions each extending in a perpendicular direction from the base to a respective distal end, each respective distal end of the plurality of extension portions abutting the end surface of the outer peripheral iron core at separate respective locations, the plurality of extension portions spaced apart from each other on the end plate to form ventilation ports between the end surface of the outer peripheral iron core and the end plate,
• wherein the outer peripheral iron core has a plurality of holes extending in an axial direction, and each of the plurality of extension portions has a respective hole extending in the axial direction from each respective distal end of the plurality of extension portions, and
• wherein the holes of the outer peripheral iron core and the holes of the extension portions are aligned, such that the attachment unit and the outer peripheral iron core are connected with screws extending through the holes of the outer peripheral iron core and the holes of the extension portions.