The development and integration of high voltage/high temperature components that can be space qualified will lead to increases in system level performance as they will tend to increase efficiency and decrease mass at the system architecture level. Such performance improvements are necessary if NASA is to realize several operational concepts such as very high power Solar Electric Propulsion (SEP). In a simplistic but specific realization, higher voltage parts allow power generation at higher voltages on the arrays themselves, this higher voltage allows for the same power to be transferred at lower current thereby reducing cable mass at the system level.
Silicon MOSFET?s seem to be reaching the ?end of the road? as far as improvements to the technology for power, speed and performance. SiC MOSFET technology offers high-temperature and high-power operation far superior that that of Silicon MOSFETs. It is generally felt that SiC is early in its life cycle and there are many applications that could benefit from this technology. SiC extreme high electron mobility and low temperature coefficient enables a very low RDS(ON). This device would have superior switching characteristics due to the high critical field, high electron mobility, high saturation velocity and low gate-drain capacitance of the SiC device. This also allows for short delay times and excellent controllability in low duty-cycle applications. SiC devices also have significantly lower output capacitance when compared to Silicon MOSFET?s of similar RDS(ON). SiC offers the benefits of the least power consumption while providing for the lowest energy loss at extremely high temperatures requiring limited external cooling.
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