基于工质焓值的核电机组模型一、二回路传递功率计算方法

A New Method for Calculating Transfer Power Between Primary and Secondary Systems of Nuclear Power Units Based on Enthalpy Drop

针对现有电力系统稳定计算中核电机组模型一、二回路系统之间传递功率难以准确计算的问题,利用核汽轮机饱和湿蒸汽的特点,基于工质焓降原理,提出一种一、二回路系统模型之间的接口方法。通过拟合主蒸汽及给水的比焓,同时考虑旁排与机组热效率,采用计算单位时间内焓降的办法,实现了对核蒸汽供应系统与原动机间传递功率的准确模拟,克服了现有简单套用火电汽轮机入口功率计算方法造成模型动态误差过大的缺陷,提升了核电模型的仿真精度。全范围仿真结果表明,该方法可较为准确地反映核电机组一、二回路间功率变化的动态过程,为研究核电机组与电网之间的相互影响和协调控制提供了技术支撑。

To solve the problem that the transfer power between primary and secondary systems of nuclear power unit models cannot be accurately calculated in power system stability analysis, a new method is proposed using enthalpy drop of wet saturated steam flow in the turbines. The enthalpy drop per unit time in steam generator, combined with thermal efficiency and fitting curves of the enthalpy of main steam and feed water, is used to simulate the power transfer between nuclear steam supply system and prime mover. It improves dynamic simulation accuracy of the nuclear power unit model. The full scope simulation results of the reference nuclear power unit show that the dynamic transfer process can be accurately calculated. It can be used for analyzing interaction and coordination between nuclear power units and power systems.