Module Stellarator System Made of L =±2 Helices with Different Pitch Angles

Abstract

A new design method for the modularization of helical coils of a stellarator type has been proposed. This is an extension of the interchangeable module stellarator (IMS) method, and L=±2 helices with different pitch angles are utilized. This modular coil system exerts less error field effects on magnetic properties, so it may have large magnetic surfaces. The magnetic axis exists nearly at the coil center without any additional fields. It may have larger transform than that designed from the original IMS method.