Shaun Wright-Phillips insists he is happy again at QPR after turning down "offers and opportunities" to move in January.
Blackburn goalkeeper Paul Robinson has told Sky Sports he will leave the club this summer and could move abroad.
The 23-year-old has signed a three-year contract at The Valley and becomes the Championship club's ninth new recruit of the summer.
Tucudean has flown out to Charlton's training camp in Spain and could feature in their friendly matches against a Gibraltar XI on Wednesday evening and Atletico Clube de Portugal on Saturday.
He follows Yoni Buyens, Igor Vetokele, Franck Moussa, Andre Bikey, Tal Ben Haim, Johann Berg Gudmundsson and youngsters Zak Ansah and Kurtis Cumberbatch in moving to The Valley this summer.