The Fault Tolerance Design of Digital Control System in Korea

摘要

Among the 20 operating units of Nuclear Power Plants (NPPs), 8 units have adopted digital control system instead of conventional control system since 1987 in Korea. Additional 6 units are under construction and they are designing the control system using the advanced features of the digital control system. In case of SKN 1&2 and SWN 1&2, redundant multi-loop control cards are used combined with the control switches, while introducing the screen-based soft control for the radwaste control system. The latest two units(SKN 3&4) are being designed using the concept of complete soft control. Analysis and study was performed on the failure of the communication system of the digital control system, the output signal condition due to the failure of the control card, the fail position status of the interface equipment, and their effects on the operation. This study was to contribute to the stable operation, the improved performance and the maintenance by maintaining the proven equipment status in case of failure and also to utilize them in the design of the future digital control system.