Oddly for a patent, the language here appears potentially ambiguous, so it may be necessary to proceed with caution.

First of all, this 'driving power' — it is not clear from the text given if this is simply 'power used to drive this unit'; in which case using both 'driving' and driven' together like this appears slight overkill!

BUT maybe what they means is 'the driving power used to propel the vehicle' — as distinct, say, from some other auxiliary source of power. In that sense, the reason for using 'driven' (= this unit) and 'driving' (= the vehicle as a whole) would be clear; this is what I have suggested above with the use of 'motrice'.

Again, 'power' is not without ambiguity; given this is a patent, I'm assuming they are seeking to avoid tying it down to any specific form of power, such as electrical, mechanical, etc. In which case, my instinctive feeling (albeit as a non-native speaker) would be that 'force' is more appropriate here than (say) 'énergie'.