EFFICIENCY IMPROVEMENT USING PHASE SHIFT FULL BRIDGE CONVERTER

A server power system is generally composed of three different parts, a power factor correction (PFC) stage, a front-end dc/dc converter stage, and a point of load (POL) stage. The PFC stage is used to achieve unity power factor of the system and galvanic isolation and main output voltage regulation are accomplished in the frontend dc/dc stage. Among these parts, the front-end dc/dc converter stage is chosen to be the most critical part to improve the efficiency of server power system because it converts high voltage/low current input into low voltage/high current output, which results in large power loss. In the POL stage, some of total output power from the front-end dc/dc converter is converted to many different levels of load voltages, which are required in server computer.