A magnetic part includes: a magnetic core; a first winding; a second winding that is not short-circuited with the first winding; and a third winding, wherein the first winding, the second winding, and the third winding are wound around the magnetic core, a first magnetic flux is generated in the magnetic core by a first electric current flowing through the first winding, a second magnetic flux is generated in the magnetic core by a second electric current flowing through the second winding in a direction same as the first electric current, a third magnetic flux is generated in the magnetic core by a third electric current flowing through the third winding in a direction reverse to the first electric current, and the first magnetic flux, the second magnetic flux, and the third magnetic flux strengthen one another.