Research on protection control strategy of pressurized water reactor nuclear power units for typical power system faults.

• Based on MATLAB/Simulink simulation platform, a simulation model of nuclear power unit is built and verified. • According to two typical faults in power system, the influence of grid faults on the operation characteristics of nuclear power units is studied. • According to the fault condition of power system, the influence of the difference coefficient of primary frequency modulation and frequency modulation dead zone on the operation characteristics of nuclear power units is studied. • The influence of overspeed protection controller on nuclear power units is analyzed and an optimized overspeed protection scheme is established in view of the load step drop condition caused by failure of fault cutting. With the development of nuclear power industry in China, the proportion of nuclear power generation in the total power generation is constantly rising. As the power system is always faced with the threat of faults of different degrees, these faults will not only affect the power quality, but also are potential risks for nuclear power units with high safety requirements. Therefore, it is necessary to study the influence of typical power system faults on nuclear power units. The corresponding control strategies for typical power system fault conditions are studied. The primary frequency regulation (PFR) parameter optimization scheme and overspeed protection optimization scheme proposed in this paper can effectively solve the frequency disturbance and steam turbine overspeed problems caused by power system faults. The research results can provide reference for large PWR nuclear power units to deal with typical power system faults, and have certain engineering application value. [ABSTRACT FROM AUTHOR]