Here's the datasheet for the UC2909/UC3909: http://focus.ti.com/lit/ds/symlink/uc2909.pdf
Scroll to the bottom of page 8, and look at "Figure 3. Off line charger with primary side PWM"
So far I have an idea of how I am going to power the individual 12 and 24V charging circuits. I am determining which regulators I am going to go with and going to do some testing with LT Spice. But, I can't get past the issue regarding the input voltage range that I am working with. If you don't mind, would you be able to offer some places where I can read up PWM an ac signal?
Look up the topic of buck regulators in google. You have to use buck regulation if you don't have a step-down transformer otherwise you are going to have a dangerous situation and a lot of heat. Basically, you need a switching type regulator, another topic to google.
I've been doing more research on parts and it seems that I might have make several models. Obviously, I wanted to make just one model to work with my universal input voltage to charge 12 and 24V batteries. I just can't find any transformers to work at such a wide range.