Design (Block diagram/topology) of high-current (I>100 A) power supply
You can use a multiphase buck converter such as this one: -




Input is 30 volts to 70 volts
Output is 12 volts at 180 amps (2.16 kW)


Note that this is a 6 phase device and the full circuit is shown in the data sheet on page 46.

To get down to the required input voltage range for the LTC7871 use an isolating forward converter to produce circa 50 or 60 volts (45 amps) from the power factor corrected rectified input AC voltage.