Burning Smell. A electrical burning smell was coming from behind the frezer. Unplugged it and

Question

A electrical burning smell was coming from behind the frezer. Unplugged it and smell went away. Wondering what I should replace first. The freezer was working ok at the time.Had a power outage today.
When power was restored I smelt a electrical burning smell coming from the bottom of the fridge/freezer and then it tripped the electrical safety switch and I could not reset safety switch untill fridge was unplugged.
What is possibly wrong with it and has the power outage got anything to do with it(sudden power surge?).