"I knew I to make an impression but I feel like I did well and enjoyed my time here," Rigg told BBC Radio Stoke.
"It was a matter of getting my head down, doing what I could and making a new start, which I'm happy to do."
Manager Micky Adams added: "He has the intelligence to play numerous positions and I think potentially he's a good footballer."
Rigg made 26 league appearances during his loan spell at Vale Park, including 17 from the substitutes' bench, scoring three goals.
He becomes the seventh player to commit his future to Vale since the end of the season, with Anthony Griffith, Kris Taylor, John McCombe, Chris Martin, Lewis Haldane and Marc Richards all signing new contracts.
The move will become official when the transfer window opens on 1 July.
Source: BBC Sport
Source: BBC Sport