Abstract: Due to the displacement between armature and stator axes of helical explosive magnetic flux compression generators(HMFCGs), the continuous contact between stator and expanding armature may be altered to skipping, which is a major factor affecting output characteristics of HMFCGs because the flux pocketed in the skipped portion is lost. The condition of flux loss because of displacement between armature and stator axes of simple cylindrical and conical generators is mathematically analyzed, and a brief expression is derived which can be used to determine the exact condition of a given generator geometry. Based on the expression, identification of turn-skipping condition and calculation of turn-skipping ratio of a given generator geometry can be obtained by numerical calculation code on Matl