Yes well there are a number of factors which coincidently can cause your circuit breakers/rcd to trip.
first thing we always do, as with any fault on a circuit is to isolate and make safe. your safety is our main priority.
now if you have had a new consumer unit installed by a qualified electrician, then it would be safe to say that the wiring regulations and circuit parameters should have been met in accordance with bs7671, although we would test to prove this ensuring the electrical supply is safe to work on.
we would then need to determine the route in which fault is being introduced to the circuit, i.e a short circuit or an earth fault.
this can be determined by a simple insulation resistance test between the conductors. disconnecting the cooker and testing individually would be the best way to localise the fault and further provide a more accurate diagnostic.
i this case it sounds like a build up of voltage leaking somewhere on the circuit of cooker “nuisance tripping”.
easily fixed once faulty parts are located removed and replaced.
(apologies with the lack of capital letters in this answer, for reasons unknown, the site showing only lower case)