Despite the Moon having a low conductivity surface anyway - the question for me would be, is there any point in Luning what will (at least in the short term) be a DC power bus system?
For exactly the same reasons as we earth power systems here.
With the power supply derived from solar and/or Radio isotope Thermoelectric Generators, coupled with battery storage, I can't see the benefit in having AC systems, at least to begin with.
To an extent, yes.
But going DC isn't as simple as it first seems.
If you have battery storage, then you have choices to make :
DC-DC conversion (both ways) between battery and bus to maintain fixed bus voltage. There's power loss, weight, and volume as downsides to this method.
Let bus voltage change with battery voltage. That eliminates the big DC-DC converter, but then all your loads become larger. Each DC;DC converter attaching a load is sized on voltage and current. It now needs to be designed (from an insulation * electronics voltage rating PoV) to suit the maximum bus voltage, while everything also has to be sized to support the higher current at minimum bus voltage. So effectively every device becomes bigger. With large loads, that can be a significant issue.
Why might one want a fixed reference?
If one had absolutely no 'earth'-refencing, then I can't see that there would be any point in 'fault protection'. The only hazard w would then presumably resullt from someone touch both sides of the supply simultaneously - and nothing can protect against that, since a human (or alien
) body would be indistinguishable from any other 'load'?
Where to start !
I guess the first point would be to look at the regs for having an IT system. Considering the people involved, I guess that would be allowed as all would be trained in various things, and the system would be run by "skilled persons".
But being IT doesn't make it touch safe - far from it. A typical large power system has a lot of capacitance and leakage (mostly capacitance, think big filters in DC-DC converters for starters), so it will be very much "earth" referenced when it comes to touch voltages.
What IT does give you is the ability to continue operating in the presence of a single line/"earth" fault. As soon as one of those occurs, the rest fo the system is definitely not touch safe.
And of course, with an IT system, you must have an "earth" fault detection system - otherwise you will not know when that first fault occurs, so will not be able to clear it, and so will be no better off than with a TT or TN system.
