Research And Application Of Performance Improvement Technology For CPR1000 Nuclear Power Units

In recent years,nuclear power has become an important part of China’s energy strategy.In September 2019,"Nuclear Safety in China" was issued,which clarified China’s determination and action for safe and efficient use of nuclear energy.By June 2019,China had 47 nuclear power units in operation,ranking third in the world,and 11 nuclear power units under construction,ranking first in the world.China’s nuclear power units have gone through many stages of development and different models have different characteristics.However,to ensure nuclear safety and improve the economic benefits of nuclear power units has always been an eternal topic in the field of nuclear power.This research,taking the CPR1000 Nuclear power unit of a southeast coastal nuclear power plant as an example,the typical situation of unit output reduction or limitation of each unit since the first unit commercial operation of the nuclear power plant is analyzed,the factors affecting the power generation capacity of CPR1000 Nuclear power generation unit are analyzed,and the solutions of each influencing factors are calculated and studied.The main research contents are as follows:(1)The research analyzes the characteristics of CPR1000,analyzes the main factors that affect the output capacity,and expounds the analysis method of the thermal performance of CPR1000;(2)The calculation and analysis of the influence of the leakage of the main steam system on the output of the unit are given.The system model of the leakage of the main steam system is established and verified by the example test;(3)Modeling and analysis are carried out for the troubleshooting of the whole thermal system of the secondary circuit of the nuclear power unit,and the application example analysis is given;(4)For the problem of low outlet pressure at the secondary side of the steam generator,the influence on the overall performance of the unit is calculated and analyzed in detail,the causes of scaling at the secondary side of the steam generator are studied and analyzed,the heat transfer model is established,and the short,medium and long-term solutions are given.(5)Aiming at the problem of nuclear thermal power and electric power fluctuation of CPR1000 unit,the adjustment possibility of electric power limitation is analyzed,and the optimization scheme and verification result of thermal power control mode are given.In view of the problem of affecting the output of CPR1000 units,the relevant research in this paper has been verified in the previous overhauls of a nuclear power plant.Up to now,the total output of four units of a nuclear power plant has been increased or restored to 27 WM,with obvious economic benefits.This research is of great significance in the industry.