Electric blanket controllers and inverters

Has anyone come across electric blankets with analog controllers. We have cooked three electronic controlled ones over the last few years due to what turns out to be a problem with the type of power that comes off inverters. When we are on generator or shore power there is no trouble but if we forget to unplug the blanket when we head down the road and have the inventor on for some reason it cooks a large bit of electronics inside the controller, actually gets hot and smells like cooked plastic and melts part of the controller. My sweetie likes to have it keep the bed warm for her and when we have an opportunity to boondock it leaves her less than uncomfortable for the night which makes for things being testy. Thought maybe a heated throw would work but haven't found one with a manual controller. They all seem to have the auto shut off as a feature which means they will be electronic. Does anyone understand why the inverter power is such a problem? Thanks for any help possible.