Any way to run the power cord to an adjacent power pole?
If the campground voltage is low due to load the current draw of your devices would go up possibly beyond the capacity of the breakers. So it may be doing its job by tripping due to overload. I'm remembering my semester of electrical engineering that Power = volts x amps. The power is what the a/c requires and the volts is the campground level (normally 120 +/- 10%.
I'm no electrician but I have replaced c/b in home panels when the breakers went bad.
The c/g electrician should have one but a clamp on ammeter is available from many sources for less than $20. It would measure the a/c current but you have to separate the conductors since one cannot clamp on the entire power cord.