'Institute of Electrical and Electronics Engineers (IEEE)'
Abstract
The Caltech spheromak experiment uses a size A
ignitron in switching a 59-μF capacitor bank (charged up to
8 kV) across an inductive plasma load. Typical power levels in the
discharge circuit are ~200 MW for a duration of ~10 μs. This
paper describes the setup of the circuit and the measurements of
various impedances in the circuit. The combined impedance of the
size A ignitron and the cables was found to be significantly larger
than the plasma impedance. This causes the circuit to behave like
a current source with low energy transfer efficiency. This behavior
is expected to be common with other pulsed plasma experiments
of similar size that employ an ignitron switch
