No abstract

No abstract

NationalAeronautics and

Advanced power systems which generate, control, and distribute electrical power to many large loads are a requirement for future space exploration missions. The development of high temperature insulating materials and power components constitute a key element in systems which are lightweight, efficient, and are capable of surviving the hostile space environment. In this work, experiments were carried out to evaluate film and ceramic capacitors for potential use in high temperature applications. The capacitors were characterized in terms of their capacitance stability and dielectric loss in the frequency range of 50 Hz to 100 kHz at temperatures of 20 "C to 200 "C. D C leakage current measurements were also obtained as a function of temperature. The effects of thermal stressing, in air and without electrical bias, on the properties of the capacitors were determined as a function of thermal aging up to 12 weeks. The results obtained indicated that short-term thermal aging had minimal influence on the dielectric properties of both the teflon and ceramic type capacitors that were characterized in the frequency range of 50 Hz to 100 kHz at temperatures of 20 "C to 200 "C.

No abstract