Design optimization of linear transformer driver (LTD) stage cell capacitors

Optimizing the design of linear transformer driver (LTD) stage capacitors is important to achieve a very low inductance and short pulse output in pulsed power generators. The stage consists of many LTD capacitor cells. The LTD performance is dependant on the characteristics of each capacitor. The capacitor construction causes distributed transmission line properties that impact the transfer of energy in terms of efficiency and time. This paper focuses on the characterization and analysis of linear transformer driver (LTD) cell capacitors in pulsed power generators using both an analytical equivalent circuit model and a SPICE simulation model. The new models of the capacitor were verified through frequency (1 MHz to 50 MHz) and time domain measurements. The measurements of the capacitor´s behavior provided insight for the comparison between the analytical and SPICE models. The results were matched to the models representing the capacitor. In addition, placements of tabs, connecting to capacitor windings, were characterized to determine impact on the performance of the capacitor