This paper reports on a study into the effect of trigger voltage polar
ity and main gap voltage polarity on the switching performance of a pu
lse charged trigatron. The four polarity combinations possible, two ho
mopolarity (trigger voltage and main gap voltage of the same polarity)
and two heteropolarity (trigger voltage and main gap voltage of oppos
ite polarity), were studied and compared in terms of their effect upon
the switching range, delay time to breakdown, jitter, and voltage col
lapse time. It was found that the two heteropolarity configurations we
re superior to the homopolarity configurations in terms of the above s
witching characteristics, with the positive trigger/negative main gap
heteropolarity configuration performing the best. The results are disc
ussed, and an explanation of the influence of the polarity configurati
on on switching is suggested in terms of the discharge initiation mech
anisms and subsequent development.