AP1000 shutdown operation

Westinghouse Electrical Company developed the third generation AP1OOO technology. The first reactors have been built in Sanmen and Haiyang of China. Now, these two sites have been in commissioning phase. Thus it's necessary to study operation of AP1OOO deeply, which includes some new design especially. These new design features result in significant changes in unit operation, especially in shutdown operation, comparing to traditional pressurized water reactor. This paper introduces some major operation and cautions, identifies pressure and temperature limitation and control method during shutdown operation, summarizes limiting condition of operation and major risks during various modes and conditions. It's helpful for the technical commissioning and operation personnel to understand the shutdown operation of the plant. (authors)