Hi and welcome to the forum. We are probably going to get more advice and information than you can absorb with that question from a lot of experts on this forum. I'll try to just give you some generic information that might help you since I have no idea what your setup looks like or now much power you actually use
Just so you know: Charging from your truck trailer connection is only going to give you maybe 10 amps/hour into your battery. If your TT is like most (mine included) with your Refer running on propane and not using anything else except the standard parastic loads (radio memory and detectors) you are using approximately 20 AH per day so you are at a negative of 10 AH per day minimum using this method, and that doesn't include using lights. If you are a very very lite power user and you have a big 12volt battery you might be able to do a week using this method before the battery becomes too weak to power the trailer but you are slowly killing that battery
A better way to do what you are doing is to use jumper cables from your truck to the TT battery. You can replenish that ~20 amphours and more in the 1 hour you are running the truck.
The easiest way to do what you want is get a generator and charge your battery through the power cord using the converter for around 3 hours a day. If you want a really quite generator (like a Honda) that is going to cost around $1000 but you can run your microwave and other 110 stuff except the AirCond (unless you get a big generator)
If you don't need 110 volt stuff then solar will do the trick quitely and automatically. A 200Watt solar system self installed in going to run you around $500
If you plan to do a lot of boondocking (drycamping) I would personnally recommend you get a dual battery setup (most including me use 6v golf cart batteries) and at least the 200W solar setup.
