Power is provided by the exhaust turbine, which drives the inlet turbine to generate pressure.
But the oil from the PCV valve is fed into the inlet air, before that air enters the turbo (it has to be fed in befor the turbo, because after the turbo the pressure is too high). Thus the oil in that air enters the turbo, the intercooler and then back into the engine.
Whether you need oil in the turbo's chamber is a different question entirely and depends on whether the turbo's bearings are connected to the engine's lubrication system. If it is, then adding oil to the air going through the turbo should not be advantageous in any way whatsoever. The reason I say this is because there should be no contact between the turbo impellors and casing, and there are oil seals between the chambers and the bearings, so this oil cannot reach the bearings anyway. The oil in the bearings is pressurized far higher than the air in the chamber anyway, so if the seal fails, the oil in the air still won't reach the bearings, instead the oil from the bearings would enter the air and the engine would lose oil pressure.
I personally remain to be convinced that recirculating the oil can be advantageous to the engine in any way, and the only advantage I am aware of is cleaner emissions.
.... I have taken my breather off the intake and pass it through two catch bottles before expelling direct to atmosphere under the car into a chassis member under the rear seats. The amount of oil that does condense off the end of the pipe hardly collects dust, so I think it is clean enough. But give that same pipe a vacuum on it's end (like it will have in your air intake), and it creates a lot more oil vapour and soils the intake pipe fast.