Bjorklund had 11 points and 13 rebounds while Lawrence Alexander scored 12 points with a game-best seven assists as the Bison (4-0) won their home opener.
Dylan Hale sank two free throws that put North Dakota State ahead to stay 56-55 with 2:12 to go.
Felt hit a 3-pointer and Taylor Braun sank a free throw to put the Bison up 60-55 with 1:07 left.
Brown responded with three free throws to trim it to 60-58 with 36 seconds to play, but the Phoenix got no closer.
The Bison were outrebounded 42-36 but forced 18 turnovers while committing only eight.