"220V Cooling Fan" distributed power supply system is no longer a uniform supply of DC power to the system, but a system of different devices, different circuit boards, and even for the same circuit board different circuits with different power supplies. System, low frequency circuits and high-frequency circuits, small and large load current load power lines completely separated. Special "220V Cooling Fan" at low voltage and high current load using a high voltage and then transferred to the nearby load buck DC-DC conversion module supplied to the load. Power to each circuit of the system is relatively independent, reducing high current transmission line, so that the total efficiency of the system some improvement, and "220V Cooling Fan" issues of reliability and electromagnetic compatibility is relatively easy to solve.