A defensive queen sacrifice

In this game I had a defensive queen sac in mind if my opponent would have played the move 35...Qg5 :
en.lichess.org/WR3xQWV6/white#69

I have documented the queen sac in this study :
en.lichess.org/study/1HST4jZ3

very interesting game. Thanks for sharing.

It's not an actual sacrifice because you are getting the queen back and a won endgame a few moves later. I believe even I would have been able to calculate all that at a long game. I cannot do that at a 5 minutes game though!
In my recent long game against a 2200 I did a similar thing.
en.lichess.org/S4sGVLbJ
41. Rf7 Here I saw that eventually I exchange everything, losing a pawn in a process. However I also saw that I have connected passers and a won endgame because my opponent would not be able to do much on the queen side. So I was fine with losing a precious passed pawn in exchange of getting a won endgame.

@Tangelo777 #3
Nice simplification tactics with Rf7 in your game.
You had to see that a pawn breakthrough for black was not going to work out on the queenside.