Some parks definitely have power issues, specially if they're older, and these new rigs need more power, so voltage can drop across the park.
Two quick ideas, many people use a Progressive EMS that will shut down the power going to your rig if it senses low incoming voltage. These will save you from burning out the appliances you mentioned. They are a great insurance policy.
Second, you can order a plug in voltage meter from Amazon that you can plug into one of your outlets to watch the voltage, and see if it drops low, below standard 120 volts.