SiC-Based High Voltage Capacitor Charging Innovations

The Navy is currently developing a Pulsed Power System (PPS) to power an Electromagnetic Railgun (EMRG). The PPS uses a capacitor bank as the source of the very high current required by the EMRG for operation. EMRG requirements necessitate the use of a high power density (>3MW/m3) DC/DC converter capable of a 10 capacitor recharge rate per minute. This capacitor bank is comprised of 325 kJ capacitor rep-rate modules which must recharge to 10kV from the ships 650-1100 VDC power. The capacitor bank charger must have a peak-to-average power ratio of no more than 1.1 over the charge cycle. There are no direct commercial solutions to this capacitor bank charger application. In this Phase I SBIR we propose to develop a high energy density capacitor charger that has a 3MW/m3 power density that is accomplished by having SiC based multiple DC-DC converter stages that are initially paralleled then connected in series as the capacitor voltage rises, and to oil fill the charger to minimize the volume required to meet the voltage isolation and corona elimination requirements. The successful development of this technology will enables the EMRG while reducing the overall size and weight of the weapon system.