A rotor comprising: a rotor core; and a cover disposed on one axial side of the rotor core, wherein the cover comprises a first cover disposed on any one side of the rotor core and a second cover disposed on the other side of the rotor core, wherein the cover comprises a body portion and a plurality of wing portions extending in the axial direction which are formed on the axially external surface of the body portion, wherein the wing portion is disposed between an outer boundary, of the cover, which is a circular curve, and an inner boundary, which is a circular curve, both boundaries and having the same center, wherein the wing portion comprises an inside portion and an outside portion, wherein, a first point is the intersection point between a cord line between a leading edge and a trailing edge of the wing portion and the inner boundary and a second point is the intersection point between an intermediate boundary, which is a circular curve disposed between the outer boundary and the inner boundary and having the same cernter, and the cord line and a third point is the intersection point between the cord line and the outer boundary, wherein the inside portion includes a first inlet angle at a first point and a first outlet angle at a second point, wherein the outside portion includes a second inlet angle at the second point and a second outlet angle at a third point, wherein the first point is located on the inner boundary, the second point is located on an intermediate boundary, and the third point is located on the outer boundary, wherein at least one of the number and position of the wing portions of the first cover is different from the number or position of the wing portions of the second cover wherein at least one of the first inlet angle, the first outlet angle, the second inlet angle, and the second outlet angle of the wing portion of the first cover is different from the first inlet angle, the first outlet angle, the second inlet angle, or the second outlet angle of the wing portion of the second cover, characterized in that the radius of the intermediate boundary is a value obtained by adding the radius of the inner boundary to 50% to 70% of a difference between the radius of the outer boundary and the radius of the inner boundary, the second inlet angle being within a range of 50° to 70°, the first outlet angle being within a range of 60° to 80°, and the second outlet angle being within a range of 50° to 70°. a rotor core; and a cover disposed on one axial side of the rotor core, wherein the cover comprises a first cover disposed on any one side of the rotor core and a second cover disposed on the other side of the rotor core, wherein the cover comprises a body portion and a plurality of wing portions extending in the axial direction which are formed on the axially external surface of the body portion, wherein the wing portion is disposed between an outer boundary, of the cover, which is a circular curve, and an inner boundary, which is a circular curve, both boundaries and having the same center, wherein the wing portion comprises an inside portion and an outside portion, wherein, a first point is the intersection point between a cord line between a leading edge and a trailing edge of the wing portion and the inner boundary and a second point is the intersection point between an intermediate boundary, which is a circular curve disposed between the outer boundary and the inner boundary and having the same cernter, and the cord line and a third point is the intersection point between the cord line and the outer boundary, wherein the inside portion includes a first inlet angle at a first point and a first outlet angle at a second point, wherein the outside portion includes a second inlet angle at the second point and a second outlet angle at a third point, wherein the first point is located on the inner boundary, the second point is located on an intermediate boundary, and the third point is located on the outer boundary, wherein at least one of the number and position of the wing portions of the first cover is different from the number or position of the wing portions of the second cover wherein at least one of the first inlet angle, the first outlet angle, the second inlet angle, and the second outlet angle of the wing portion of the first cover is different from the first inlet angle, the first outlet angle, the second inlet angle, or the second outlet angle of the wing portion of the second cover, characterized in that the radius of the intermediate boundary is a value obtained by adding the radius of the inner boundary to 50% to 70% of a difference between the radius of the outer boundary and the radius of the inner boundary, the second inlet angle being within a range of 50° to 70°, the first outlet angle being within a range of 60° to 80°, and the second outlet angle being within a range of 50° to 70°.