Look at the AC-DC application especially the one's that have a range of 85-120Vac. I am guessing this is the range around the 160Vdc you keep on referring.
After rectification, peak voltage is 85*1.41=119V~120*1.41=169.2. To keep the bus voltage stable at the peak rectified voltage, a input bulk capacitor is used. A flyback circuit is most appropriate for your application. An application note of a flyback circuit is attached.
Switching Power Supply Design, Abraham Pressman (Author), Keith Billings (Author), Taylor Morey (Author) would be a good book to start.