I had something like that years ago after buying my house from someone that owned it since new and the electric stove had worked fine until one day it did like you said and shut down after using the oven at a high temp or broiler and when turned back on it would be weak and kick off when high temps used.

What I found was a weak breaker that supplied power to the range and would not provide enough power or trip when too much for it.

I replaced the breaker and it worked as it should since then and the oven was able to heat on high temps again.

Don't know if this is your problem, but if your house breakers are older than ten years it could be the fix.

Good luck,

Rob