AC/DC SMPS- How to do PWM
This should really be a comment since this is mostly a shopping question, but seeing how you've asked this like 3-4 times...

Poweresim is a reasonable way to get something whipped up (using TL494) when you are as inexperienced as you are with SMPS. Or use one of the easier (but more expensive) chips from various mfg. Most have their own on-line tools for doing a quick spec [just with their own chips usually]. Since you seem to have trouble finding them, here are a few:


TI: web-based "Webench" (registration req. for simulation) and downloadable
Fairchild: on-line  Power Supply WebDesigner and downloadable (registration req.)
NXP: http://nxp.transim.com/
Linear: LTpowerCAD
ON: GreenPoint
Analog Devices: ADIsimPower
ST: eDesignSuite (registration req.)
Maxim: EE-SIM (registration req.)


Avnet has a nice list: Avnet - Power Simulation Design Tools by Supplier

There is a longer list: Power Electronics Design Simulation Analysis Tools at PowerGuru.org

Alas it has proven difficult to find a recent [comparative] review of these on-line tools. I found one from 2004, which is very dated.

And for recommendation on more in-depth/background material: Reddit - Good Resources for Learning SMPS Design for ACDC