To provide a method and a device for winding a conductor while it is being twisted to minimize a loss in alternating currency of a superconductive conductor used in a coil in a device capable of storing an energy as magnetism, by allowing the superconductive conductor that an electric resistance is zero at a critical temperature or less to be coiled and allowing current to flow in the coiled conductor.

Paying an attention to a fact that a loss in alternating current (coupling loss) of a magnetic field applied to a superconductive formed stranded wire present in the interior of the conductor is minimized when the magnetic filed is in parallel with the stranded wire, the coupling loss can be decreased if winding is performed on each conductor in the cross-section of the coils while the conductors are being twisted so as to align a pre-calculated magnetic field angle with the conductor angle as shown in Fig. 1.