The former Chelsea goalkeeper moved to Dean Court last month.
Petrovic told the club's website: “Firstly, I’m really happy to be here. From day one, everyone helped me settle very well to be honest. I think we have a really good group of people and I’m excited for what is to come.
“It’s been very helpful having most of pre-season here because, for almost all of it, I was with the team. I now know what I have to do and I am prepared for the season.
“It is very important for me to be settled here and to have time to settle my life outside of football too.
“As much as being with the team helps, I’m really happy to have gone through the whole pre-season with the coaches and the coaching staff too. It’s important for me to take all the information in and find out what they want from me.
“It's also about learning the mentality of the club and the people around, that is very important to know what you have to expect and how to be. You have to be prepared for everything.”