High energy density capacitors for ETC gun applications

Driven by the significantly reduced electric energy requirements of large caliber ETC guns applied with improved electrothermal plasma ignition methods capacitive pulsed power supply technologies are becoming a dominant solution for the integration of such weaponization into the structure of a combat fighting vehicle. Due to the limited weight and volume restrictions given in such vehicles integrated and reliable pulsed power supply modules with high energy density components have to be developed fulfilling the electric requirements of the applied ETC technology in terms of discharge current, discharge power, pulse shape and pulse duration. One of the most critical component of this PPS technology is the high voltage discharge capacitor itself. Therefore currently running investigations within the German R&D program on ETC PPS technologies concentrate on the feasibility and the development of high energy density capacitors which electrical characteristics are matched properly to the requirements of an electrothermal plasma ignition system of a large caliber ETC gun. The paper gives the latest results of the ongoing investigation. Based on the electric requirements of ETC guns, capacitor windings made from conventional dielectric materials with improved metallization and impregnation technologies are developed and tested. Up to now energy densities of up to 2.7 MJ/m³ were obtained with these windings. Based on the results, a full scale ETC capacitor was set-up containing 118 kT electric energy at full charge voltage of 35 kV with an energy density of 2 MJ/m³. First discharge tests were performed successfully with this capacitor leading into the continuation of the selected approach. The paper concludes with a summary of the results and with an outlook on the further procedure