Scaling of operation of a low magnetic-field microsecond plasma opening switch

An inductive voltage adder/inductive energy storage pulsed power generator, ASO-X, with a microsecond plasma opening switch (MPOS) is designed to drive a Z-pinch load. For good performance of a Z-pinch load, the load inductance between the MPOS and Z-pinch load should be low. To satisfy this requirement, the inner coaxial diameter of ASO-X and the length in the MPOS are 80 mm and 150 mm, respectively. The operation of the MPOS is strongly affected by the self magnetic field in the coaxial pulsed power generator. Usually, a good MPOS operation has been achieved at a magnetic field of several Tesla. The maximum amplitude of the magnetic field which is induced by the generator current of ASO-X at a charging voltage of 30 kV is less than 1 T. In spite of this low magnetic flux density, the MPOS operation in ASO-X is satisfactory. The magnetic field becomes less important if one uses a load with a very low inductance. The MPOS operation is analyzed from the viewpoint of an MPOS-Z-pinch scheme.