Vector inversion generator

VIGs are used in military technology, e.g. some directed-energy weapons, as a secondary stage of another pulsed power source, commonly an explosive-driven ferroelectric generator.

Discrete components allow large lumped capacitors to be used thus storing much more energy, but have difficulty replicating the high voltage multiplication ratios and extremely short rise times of spiral transmission line types.

A spiral VIG consists of four alternating conductor-insulator-conductor-insulator sheets, wound into a cylinder, forming a capacitor also acting as a single-ended transmission line, connected to a spark gap switch.

A pulse of output amplitude 2nU (where n is the number of turns of the capacitor and U is the initial voltage it was charged to) and a rise time equal to twice the electrical length of the transmission line.

Ferrites can be attached to the VIG construction to modify its characteristics, typically lowering the resonant frequency and increasing the efficiency.