isolated buck converter idea
By using this method, one can eliminate the cost of transformers in isolated buck converters. A control circuit will control the pulse width into the smoothing capacitor through a negative feedback loop (AKA, as the voltage on the storage cap rises to a target value, the PWM will decrease until the high current capacitor is permanently connected to the DC supply. as the voltage drops, the duty cycle will increase to a 50% maximum.)
I am just curious why this might not work, and if it does, does such a system already exist?