bicategory of fractions and homotopy category

Hi all, has anyone come across this situation? I have a 2-category where the underlying category has a model structure, and the class of equivalences (from the 2-cat structure) is contained in the weak equivalences. The class of weak equivalences admits a bicategory of fractions, and so one can consider that bicategory as the homotopy 'category' in some sense. Cheers, David Roberts