The power supply system of data room is a kind of uninterrupted power supply system for it rooms such as information center and dispatching center of the power plant and power grid. The system is the core of the entire electric system. All data that are collected from basic equipment will be transferred through information communication center. In case of the information communication room paralysis of the whole power system or the power supply failure, it will lead to the failure of the whole power system, which can no longer work normally. Therefore, the main challenge for future development is how to ensure the high reliable operation and intelligent operation and maintenance of the electric IT information room.