Voltage and Frequency for Spacecraft and Moonbase Systems

Electrical components and mechanisms can be produced in any voltage or frequency. Since airplane avionics are all 28 VDC, however, the spacecraft and exploration base should be the same in the interests of using low-cost, existing parts.

In the early days of the space station, there was a movement to use 240 VAC at 20,000 Hz for the main power transmission buss. The argument in favor of the higher frequency is that the components are smaller and more efficient, and the high frequency is beyond the range of human hearing. However, since this would have required the great expense of new technology development, the space station program decided on the standard voltages and frequencies.