I have no scientific reasoning behind this... just observations over the years.
If you played good opponents the last few games, go back and look at some old games. I honestly believe there is a correlation between high driving and drawing fouls. Especially if your big guys do not have decently high shot blocking.
So if you are always on the high side of fouls playing against top tier teams, that is a possible explanation for your problems.
You will also see more fouls if you are playing someone who is attacking you inside. There are just so many more shots inside the paint where the big guys have a chance to foul.