CPR1000核电机组延伸运行优化控制

延伸运行（SO）是压水堆核电机组灵活运行的重要手段，研究如何提升机组SO模式下的安全性和经济性具有重要意义。针对某中国改进型三环路压水堆（CPR1000）核电机组某次SO模式下一回路平均温度、堆芯热功率、堆芯轴向功率偏差和温度调节棒棒位等重要参数存在波动的案例，研究表明波动的主要原因是由于该CPR1000核电机组的汽轮机高压调节阀运行在流量特性曲线的陡峭区，导致阀门开度在外部扰动影响下产生波动，并诱发主蒸汽流量、一回路平均温度等重要参数的波动。结合该核电机组设备的运行特性，提出优化高压调节阀流量特性曲线和优化主蒸汽流量限值等策略来提高机组SO期间安全性和经济性。数台CPR1000核电机组采用SO模式的工程实践案例验证了该策略的有效性。 

Optimal Control of Stretch-out Operation for CPR1000 Nuclear Power Unit

Stretch-out operation (SO) is an important means of flexible operation for PWR nuclear power unit. It is of great significance to study how to improve the safety and economy of the unit under SO mode. For the case of fluctuation of important parameters such as primary loop average temperature, core thermal power, core axial power deviation and temperature regulating rod (R rod) position of a Chinese improved three loop pressurized water reactor (CPR1000) nuclear power unit under SO mode, relevant research shows that the main reason is that the high-pressure regulating valve of the steam turbine of the CPR1000 nuclear power unit operates in the steep region of the flow characteristic curve, which causes the valve opening to fluctuate under the influence of external disturbances, and induces fluctuations of important parameters such as main steam flow, average temperature of primary loop, etc. Combined with the operation characteristics of the nuclear power unit, strategies such as optimizing the flow characteristic curve of the high-pressure regulating valve and optimizing the main steam flow limit are proposed to improve the safety and economy of the unit during SO. The effectiveness of the strategy is verified by several engineering cases of stretch-out operation of several CPR1000 nuclear power units.