Research On RAMS Management System And Key Technologies For Nuclear Power Plant Digital I&C System

As the key system of the Nuclear Power Plant(NPP),the digital Instrumentation and Control(I&C)system can be evaluated in aspects of Reliability,Availability,Maintainability and Safety,and can be improved by adopting the RAMS management system.More reliable I&C system will further improve the safety and economy of the NPP as the direct consequence.This paper systematically studied the RAMS management theory including the RAMS organizational arrangements theory,RAMS management actions construction theory and RAMS management operation evaluation theory(i.e.RAMS organizational capability theory,RAMS technology maturity evaluation theory),and set up the RAMS management model for NPP digital I&C system development.Based on proposal of IEC 60300-1 guidelines,this paper developed the RAMS management framework and construction method for NPP digital I&C system,including the RAMS organizational arrangements method,RAMS management actions scheme,RAMS performance evaluation method and key RAMS techniques identification method based on Quality Function Deployment(QFD).On this basis,the RAMS management system applicable to NPP I&C system is established for the first time in the field of nuclear industry in China.The RAMS management system includes RAMS working procedure,technical specification and working templates in product development / engineering application stage of the project.The successful implementation and optimization of RAMS management system for Chinese indigenous NPP digital I&C system,ensured the successful launch of the Firm Sys system,which is the first safety class NPP I&C system.In addition,the identification method based on QFD is applied to determine two key technologies of RAMS for NPP I&C system of CTEC(intelligent diagnosis and cyber security)and the corresponding technical research is carried out.After the practice of implementation of the RAMS management system in CTEC,the following results have been achieved:1)The coverage of organization RAMS capacity,the applicability of the RAMS work procedure and the activity normalization in the Firm Sys project are increased by 20 percentage points.2)Through applying of intelligent diagnosis technology,local alarm manner of NPP I&C system is optimized,such as the reduction of monitoring equipment,extension of alarm indicator category,and reduction of maintenance time(more than 20%).Meanwhile,the remote maintenance technology could send equipment real-time diagnosis information and system log information to the operation and maintenance management platform(Center)to achieve remote real-time monitoring of equipment status,which is the first implementation in the field of remote operation and maintenance for NPP.3)Research on the cyber security technology has optimized the cyber security defense scheme of NPP I&C system,and realized the first NPP I&C system that meets the requirements of China security protection level 4 in China's nuclear power field.