Classification Analysis of Communication System of Nuclear Power Plant

The communication system of nuclear power plants in China is not a safety class system, but it plays an important role in the safe operation of nuclear power plants. Under emergency state, the communication system is a prerequisite for accident management. In order to ensure communication on-site and off-site, diverse communication sub-systems are designed throughout the nuclear power plant, including various communication means for voice, data and images. For an advanced generation II pressurized water reactor (PWR) nuclear power plant (NPP) in China, there are various subsystems, including normal telephone system, safety telephone system, grid telephone system and so on. Although NPPs have designed diverse communication sub-systems, there is not any clear classification of the sub-systems, which is not enough for the reliability of communication sub-systems under accident conditions. Therefore, it can hardly ensure effective communications between different emergency response organizations and this will influence the mitigation of the accident. In order to identify the importance of different communication sub-systems, to optimize the design of communication system, and to improve the reliability and efficiency of nuclear power plant communication system, it’s necessary to analyze the function and operation of each sub-system, as well as to develop the classification method of nuclear power plant communication system. Considering the availability and reliability of onsite and offsite communication under emergency conditions, slightly considering economic issue, this paper determines 7 assessment factors and develops a set of scoring methods for communication system classification. On this basis, this paper completes the classification of the communication system for an advanced generation II PWR NPP, which provides a reference for communication system classification and provides the technical basis for design modification of the communication system.