功率控制棒棒位标定试验堆芯过热分析

核电机组在并网前的启动物理试验,需要完成一次功率控制棒负荷曲线标定试验（RGL04试验）。试验的内容是通过快速降负荷来校核事先输入的功率棒棒位与汽轮机负荷的对应关系曲线（G9曲线）。宁德、阳江等CPR1000机组在该试验中先后出现堆芯过热较大现象,对可能导致试验过程中堆芯过热的各种因素进行了分析与评估,通过计算等温温度系数理论值来预测堆芯的过热度,并给出了过插控制棒的建议措施来降低试验中堆芯的过热度。

Overheating study in power plant control rod banks calibration test

Power control banks-turbine load test (RGL04 test) is to be performed to verify the accuracy of calibration curve by quickly reducing the power before nuclear power plants connecting to power grid. Overheating phenomenon occurred during the tests in CPR1000 units of nuclear power plants in Ningde and Yangjiang units. This paper analyzes and evaluates the causes and the factors that lead to overheating during the RGL04 test. The overheat of the core can be predicted by calculating the theoretical value of isothermal temperature coefficient. A sound advice to avoid large superheat is given at the end of this paper.