I have 10 years work experience and a masters. I have been desiring to do a PhD for some time now. Is it possible to do a PhD in 3 years from a top 50 university ?
No, I don't think you'll be able to do it in 3 years, though I think 4 might be a possibility. If you want to get into academia, you might need more time than that, though, in order to establish a publication record before going on the job market. Ultimately, you're going to need to tell us what field you're thinking about before we can give advice.