Catalysis of the reaction: 3'-phosphoadenylyl sulfate + alpha-D-glucosaminyl-(heparan sulfate)(n) = 3-sulfo-alpha-D-glucosaminyl-(heparan sulfate)(n) + adenosine 3',5'-bisphosphate + H+.
heparan sulfate D-glucosaminyl 3-O-sulfotransferase 3 activity