变频技术在华龙一号CAV系统中的应用研究

Study on Application of Variable Frequency Technology in HPR1000 CAV System

"华龙一号"是我国具有自主知识产权的三代核电品牌,在技术上实施了一系列技术改进措施,其中包括双层安全壳设计。双层安全壳的设计不仅能抗大型飞机撞击,而且在事故情况下,反应堆压力容器、内层安全壳和外层安全壳构成多重安全防御屏障,极大地降低了放射性气体泄漏。为了精准控制双层安全壳环形空间负压,"华龙一号"双层安全壳环形空间通风(CAV)系统采用变频控制方式控制风机。重点分析了CAV系统控制逻辑方案,以及变频器技术的应用和变频技术方案的设计特点。这套变频控制系统不仅实现了精细控制环形空间压力,有效控制事故工况下放射性物质向环境释放的功能,而且在保证机组运行安全的基础上提高了电厂经济性,为变频器技术在核电厂安全级系统的推广应用起到了良好的示范作用。

HPR1000 is a generation III nuclear power brand with independent intellectual property rights,which implements a series of technical improving measures,including double layer containment design.The design of double layer containment can resist crash of big airplane,in the event of an accident,reactor pressure vessel,inner containment and outer containment constitute multiple security defense barriers and greatly reduce the leakage of radioactive gases.In order to accurately control the negative pressure of the double layer containment annular space,the fans of HPR1000 containment annulus ventilation(CAV)system are controlled in variable frequency mode.The control logic scheme of CAV system,the application of variable frequency technology,and the design features of the scheme are analyzed emphatically.This variable frequency control system not only realizes the accurate pressure control and limits the radioactive gases from inner containment to the environment,but also improve economy of power plant on the basis of safe operation,which has played a good demonstration role for the promotion and application of variable frequency technology in the safety level system of nuclear power plants.