Linear power generator

A linear power generator includes a columnar or cylindrical center yoke made of a soft magnetic material and an outer yoke made of a soft magnetic material. In the center yoke, rod-shaped permanent magnets magnetized in a circumferential direction are arranged in the circumferential direction in an outer circumference of the center yoke such that opposed magnetic poles of the permanent magnets adjacent to each other become identical, the permanent magnets are extended in an axial direction, and the center yoke includes plural center-side projecting portions linearly arranged in the circumferential direction. The cylindrical or columnar outer yoke includes plural winding portions, plural groove portions, and an outer-side projecting portion. The winding portions are arranged in the circumferential direction about a center axis. The groove portions are arranged at positions opposed to the permanent magnets.