As above, swap out smoke detector for heat detector.
In the short term though, when was the last time you cleaned the head of the smoke detector? If the air flow from new oven is stronger than the last one and there is dirt/dust in the smoke head, the air movement might be moving the dirt in the head, prompting the alarm to go off.
We've just replaced our old Neff oven with a mid-range Bosch one. Each time we open the oven door to check on food, the smoke alarm goes off. Surely this isn't usual? DP says it because the fan isn't as effective. I'm wondering if there is something else going on... but I have no idea what. We've cooked off the new oven small in accordance with the instructions. Any ideas?