You have also _ImportObj by Max Smirnov for OBJ format...

http://moi.maxsm.net/files/scripts/ImportObj.v.1.5.2015.09.10.zip
Better if your obj is "Ngons" (quadrangles is the best)
150 000 polys is reasonnable

Press Tab and write _importObj
When you have import it : Select by Browser's button "Edges" copy move them ... you have segments as support new drawing...

You can of course Sudvide after it if necessary...
The complete thread ;) http://moi3d.com/forum/messages.php?webtag=MOI&msg=6674.1
http://moi.maxsm.net/files/scripts/Subdiv_beta9.zip
Press Tab and write Subdiv_beta9 (or make a ShortCut)




You have an other native method of subdivision : SubD / Create from file (OBJ format)