Voltage stability enhancement of Class 1E bus in NPPs using voltage-reactive power controls

Presented in this study is the cooperation of voltage-reactive power controllers for securing the voltage stability when a disturbance of off-site power system in nuclear power plant is occurred. In a case of nuclear power plant, a power system is made up of redundant power system for the safety. And the power of vital loads for the safety is supplied by the Class 1E buses which are linked to offsite power system. In a recent power grid system, the voltage of off-site power system becomes unstable as the increase of renewable energy such as wind generation. In this study, the cooperation of voltage-reactive power controller is suggested to enhance the voltage stability of Class 1E buses.