"I made a point of wrapping everything up before coming to train with the national team," he told journalists at Brazil's base camp outside Rio de Janeiro, where they are preparing to launch their FIFA World Cup campaign on 12 June.
"It's a new phase, a new project, a new country, a new language," Luiz explained. "I was very happy at Chelsea, I won titles, but I had arrived at the end of a cycle. I'm going to start a new cycle in Paris.
"It's going to be announced when the (transfer) window opens. But I can already say I've reached a deal with Paris and I'm very happy to be going there."
PSG are reportedly paying £50m for Luiz, a world-record fee for a defender. Asked about playing at PSG alongside Thiago Silva, he said his Brazil team-mate and fellow defender was a "marvellous person who always makes me really happy. We've never been rivals. He's a great leader," he said.
At Chelsea, Luiz was primarily used in a defensive midfield role by Blues manager Jose Mourinho after being unable to break up the central defensive partnership of John Terry and Gary Cahill. The 27-year-old, who joined the west Londoners from Benfica for £21.3m in January 2011, made only 19 appearances in the English Premier League this season, although he did help Chelsea eliminate PSG from the Champions League quarter-finals.