What is the operating voltage of a spacecraft?

Heritage Spacecraft Operating Voltage •Low power spacecraft use well-established low voltage systems (28V DC ) with well understood interactions in space environment •Larger (>10kW) commercial communication satellites distribute 70 and 100 V DC •International Space station regulates solar array voltage at 160 V DC –Distribution voltage is 120 V

Is selection of a spacecraft bus voltage trivial?

Conclusions •Selection of a spacecraft bus voltage not trivial “But it's just ohms law” L. Pinero •System voltage decisions are often required early with limited data •Selection of bus voltage is driven by the need to minimize distribution mass and I2R loses •Channelizing distribution needs to be considered to optimize bus to bus cable ampacity

What is the distribution voltage of a solar array?

•Larger (>10kW) commercial communication satellites distribute 70 and 100 V DC •International Space station regulates solar array voltage at 160 V DC –Distribution voltage is 120 V DC •NASA is currently developing other architecture for 120V

Should voltage selection be limited based on mass and available volume?

•Voltage selection should optimize mass and available volume •Ultimately voltage selection is limited based on parts availability, plasma interactions, heritage and safety As future spacecraft power exceed 50 kW system designers will be forced to increase bus voltages beyond the norm References