The 23-year-old, who joined the club from Crewe Alexandra in summer 2012, has played in all but two of Villa's Premier League fixtures this season.
Despite not being one of the star names in the team, Petrov believes that Westwood is an unsung heroes for the Villans.
"Westy has been great," the Bulgarian told the club's official website. "Some people watching him in his position don't see what he's doing. He gives the security to the team. He does the hard work. He does the dirty work. He is there for the team."
Westwood's only goal of the season so far came during Villa's 2-2 draw with West Bromwich Albion in the Premier League last month.