I have alot of terrific suggestions for your pergola. #1 on my list would be wisteria, its a beautiful vines, grows quickly, is a lovely shade of lavendar/purple and the smell is fantastic. But the only problem with wisteria is you need a VERY strong trellis, it is very heavy and will bring it down if its not strong enough.
Also Goldflame Honeysuckle comes to mind, its different from the typical honeysuckle as its pink and then opens to yellow. This is my most favorite fragrance, it reminds me of when I was a child and we used to break off the tip of the flower and suck the sweet nectar. There is no smell like it and I have only found a spray body mist once, in my whole life that accurately duplicated the fragrance. Unfortunetly Sears stopped making it, and I had only purchased one bottle. :(
The honeysuckle is particulary fragrant at night so if you sit outside after dark it will surround you with its sweet, sweet fragrance. This is what I have growing on my trellis.
You might also want to check out Sweet Autumn Clematis, Akeba vine,or actually any climbing rose.
Hope this helps you,
Deb