Wide-Temperature High Frequency Capacitors for Power Conditioning

Phase II of the present program will produce capacitors and modules that meet the Air Force need for ultra-stable electrical properties (loss<0.1%, permittivity ~2,000<+/- 5% from -55 300 degrees C) with high insulation resistance (>>1-OhmF at 250 degrees C), and graceful performance degradation. Initial optimization work by the team of Active Signal Technologies, Alfred University, Novacap and Lockheed Martin will enable a down-selection between two dielectric formulations and two alternative processing routes based on full characterization and testing of MLCs and 6 - 10-uF modules prepared from the candidate systems scaled up and fabricated in a manufacturing plant. One material system uses niobium substitution of the baseline NBT dielectric while the other integrates the outstanding properties of a high-temperature-stable (NBT-ST) and a low-temperature-stable (PMN-ST) dielectric material. Module development will proceed from a compact low inductance prototype developed in Phase I through iterations of fuse development at the 6 and 10-uF scale to demonstrate individual drop-out of failing capacitors under extreme testing conditions without energetic or propagating damage to the remainder of the module. The down-selected dielectric system will be further refined and used to prepare a large batch of ~1-uF capacitors for manufacture of the final deliverable 20-uF fused module.