Development of Helically Winding Machine for Force-Balanced Coil and Winding Technique

Abstract

Strong electromagnetic force caused by high magnetic fields and coil current is a serious problem in Superconducting Magnetic Energy Storage (SMES) systems and magnetically confined fusion devices. In facing this problem, we proposed the concept of Force-Balanced Coil (FBC) applied to SMES and fusion devices. The FBC is a helically wound toroidal coil which balances the centering force with the hoop force. The helical winding of the FBC is modulated in order to reduce the torsional force. However, the winding of the FBC is a three-dimensional complex shape so that it may be difficult to manufacture the modulated helical windings. To overcome this difficulty, we developed a helically winding machine. In this paper, we discuss the winding techniques by using the winding machine and improve the shape of the helical windings from the view point of the reduction of the time consumed in winding the coil.