How to clean melted plastic from stove
While it may be possible to refine the exact tools when we know how the stove is structured, the main approach is always going to be physical labour.  You need to scrape/chip/peel it off.  If you're lucky, there was a layer of grease that stopped it sticking too badly.

On a glass-ceramic top you can use a scraper (a glass-scraper like a razor blade in a handle was actually supplied with mine when I fitted one, but this may not be tough enough). On the solid disc type you might be best using a screwdriver or an old paring knife.  Be careful of your hand and eyes of course.

When dealing with a similar case (a friend put a plastic tray in an oven and we only realised he'd done it when we smelt it) it proved best to wait for it to go completely cold, at which point it would chip or peel; when still warm it tended to smear and stick.  That was stainless steel wire shelves and a cast iron base so a wire brush was useful for the last bits in fiddly places.  You may not be able to use one on (all of) your stove.  You really do need to get it all off before you get it hot again.