Threshold decision is an important function of nuclear instrument control system based on physical parameters threshold decision. Because the conventional decision methods lack correlation with time and conditions, by...Threshold decision is an important function of nuclear instrument control system based on physical parameters threshold decision. Because the conventional decision methods lack correlation with time and conditions, by analyzing the existing methods, some optimized methods are adopted. Considering safety, those methods are improved in data processing algorithms, floating threshold with multiple values, association with specific working condition, etc. These measures im- prove the nuclear instrument control system in fault tolerance and fault diagnosis, especially, the shutdown number of nucle- ar power plant decreases.展开更多
In this paper,the network reliability of an actual digital instrument and control system (DICS) network is analyzed by using GO-FLOW methodology (GFM).The evaluations of common-cause failure (CCF) and uncertainty are ...In this paper,the network reliability of an actual digital instrument and control system (DICS) network is analyzed by using GO-FLOW methodology (GFM).The evaluations of common-cause failure (CCF) and uncertainty are incorporated.Three significant CCF groups (real time servers,gateways,reactor protection system) and three typical time intervals (10 min,1 h,and 24 h) are selected in the analysis.It is concluded that the network contribution of CCF accounts for over 68% of the system failure probability.The result indicates that GFM is suitable for the network reliability analysis.展开更多
Abstract In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observa- tion and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Teles...Abstract In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observa- tion and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Telescope systems usually suffer some uncertain disturbances, such as wind load, nonlinear friction and other unknown disturbances. To ensure tracking precision, an acceleration feedback loop which can in- crease the stiffness of such a system is introduced. Moreover, to further improve the tracking precision, we introduce the DOC method which can accurately estimate the disturbance and compensate it. Furthermore, the analysis of tracking accuracy used by this method is proposed. Finally, a few comparative experimental results show that the proposed control method has excellent performance for reducing the tracking error of a telescope system.展开更多
The NPP (nuclear power plant) being vital objects of an energy infrastructure must be protected against malicious actions affecting their safety, and cyber security plays a key part in attaining this goal. The paper...The NPP (nuclear power plant) being vital objects of an energy infrastructure must be protected against malicious actions affecting their safety, and cyber security plays a key part in attaining this goal. The paper considers, implemented by the authors within the project of advanced digital control system for NPP with the reactor VVER-1000, a system of unauthorized access protection, partially built up on the technology of AA (active audit) and expert system. The AA technology is based on response of the system on deviation of current signature of the automated process control system from stable state rather than on a certain signature of attack and relies on the estimation of the behavioral models of the particular digital control system. The advent of active audit reflects the current situation in the digital control systems where complex distributed platforms are used to construct automated process control system. The active audit allows one to make the digital control system functionally closed, provided that it is determinate. The methodology of the active audit does not give u external (barrier) and traditional (password, antivirus) methods of unauthorized access protection. These methods can be used when it is appropriate to achieve a required protection level.展开更多
In order to improve the power of initiating explosive warheads, besides exploring new type of high explosive, multipoint initiation technology becomes the research focus. With research on electronic safety and arming ...In order to improve the power of initiating explosive warheads, besides exploring new type of high explosive, multipoint initiation technology becomes the research focus. With research on electronic safety and arming devices (ESADs), pulse power devices and slapper detonators, a hardware control circuit was designed for multipoint initiation control system based on complex programmable logic device ( CPLD ). In addition, a real-time monitoring interface based on virtual instru- ments technology was designed by the prevailing software of Laboratory Virtual Instrument Engineer- ing Workbench (LabVIEW). It provides users a real-time status of the hardware circuit system. Mo- reover, a series of experiments were done on the software and hardware platform. The results show that the signals transmission, collection, analysis and display can be realized reliably through a serial port line. It is verified that using a serial bus controller for multiple initiators is reasonable. Successful design of the platform will play an important foundation for the theory and engineering of the fu- ture weapon system. Surely, it will become one of the development directions for intelligent initia- tion system.展开更多
人机接口设备是核电厂安全级仪控系统(Digital Instrumentation and Control System,DCS)的重要部件,鉴定试验要求在试验应力下对其进行操作,并测试其功能和性能。核电DCS设备鉴定的部分试验条件十分严酷,很难在试验中对设备进行操作。...人机接口设备是核电厂安全级仪控系统(Digital Instrumentation and Control System,DCS)的重要部件,鉴定试验要求在试验应力下对其进行操作,并测试其功能和性能。核电DCS设备鉴定的部分试验条件十分严酷,很难在试验中对设备进行操作。之前采用的方法是测试人员穿防护设备进入温箱等严酷环境进行测试,既影响了试验效率,又可能对测试人员造成健康上的损害。本文首先分析了鉴定试验的环境特点;然后提出采用步进电机进行精确控制的方法,实现对人机接口设备的自动操作;最后结合鉴定试验特点,给出对机械臂的防护措施。基于该测试方法集成的自动测试装置已投入鉴定试验活动中,并实现了远程全自动操作。展开更多
基金Research Project of Hunan Province Education Department(No.14C0972)
文摘Threshold decision is an important function of nuclear instrument control system based on physical parameters threshold decision. Because the conventional decision methods lack correlation with time and conditions, by analyzing the existing methods, some optimized methods are adopted. Considering safety, those methods are improved in data processing algorithms, floating threshold with multiple values, association with specific working condition, etc. These measures im- prove the nuclear instrument control system in fault tolerance and fault diagnosis, especially, the shutdown number of nucle- ar power plant decreases.
基金Supported by Nuclear Safety Research Association and Tohoku University for Nuclear Researchers Exchange Program 2010National High Technology and Development Program ("863"Program)of China(No.2007AA041009)
文摘In this paper,the network reliability of an actual digital instrument and control system (DICS) network is analyzed by using GO-FLOW methodology (GFM).The evaluations of common-cause failure (CCF) and uncertainty are incorporated.Three significant CCF groups (real time servers,gateways,reactor protection system) and three typical time intervals (10 min,1 h,and 24 h) are selected in the analysis.It is concluded that the network contribution of CCF accounts for over 68% of the system failure probability.The result indicates that GFM is suitable for the network reliability analysis.
基金supported by the Quantum Communication Project,one of the Strategic Pilot Projects,Chinese Academy of Sciences
文摘Abstract In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observa- tion and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Telescope systems usually suffer some uncertain disturbances, such as wind load, nonlinear friction and other unknown disturbances. To ensure tracking precision, an acceleration feedback loop which can in- crease the stiffness of such a system is introduced. Moreover, to further improve the tracking precision, we introduce the DOC method which can accurately estimate the disturbance and compensate it. Furthermore, the analysis of tracking accuracy used by this method is proposed. Finally, a few comparative experimental results show that the proposed control method has excellent performance for reducing the tracking error of a telescope system.
文摘The NPP (nuclear power plant) being vital objects of an energy infrastructure must be protected against malicious actions affecting their safety, and cyber security plays a key part in attaining this goal. The paper considers, implemented by the authors within the project of advanced digital control system for NPP with the reactor VVER-1000, a system of unauthorized access protection, partially built up on the technology of AA (active audit) and expert system. The AA technology is based on response of the system on deviation of current signature of the automated process control system from stable state rather than on a certain signature of attack and relies on the estimation of the behavioral models of the particular digital control system. The advent of active audit reflects the current situation in the digital control systems where complex distributed platforms are used to construct automated process control system. The active audit allows one to make the digital control system functionally closed, provided that it is determinate. The methodology of the active audit does not give u external (barrier) and traditional (password, antivirus) methods of unauthorized access protection. These methods can be used when it is appropriate to achieve a required protection level.
文摘In order to improve the power of initiating explosive warheads, besides exploring new type of high explosive, multipoint initiation technology becomes the research focus. With research on electronic safety and arming devices (ESADs), pulse power devices and slapper detonators, a hardware control circuit was designed for multipoint initiation control system based on complex programmable logic device ( CPLD ). In addition, a real-time monitoring interface based on virtual instru- ments technology was designed by the prevailing software of Laboratory Virtual Instrument Engineer- ing Workbench (LabVIEW). It provides users a real-time status of the hardware circuit system. Mo- reover, a series of experiments were done on the software and hardware platform. The results show that the signals transmission, collection, analysis and display can be realized reliably through a serial port line. It is verified that using a serial bus controller for multiple initiators is reasonable. Successful design of the platform will play an important foundation for the theory and engineering of the fu- ture weapon system. Surely, it will become one of the development directions for intelligent initia- tion system.
文摘人机接口设备是核电厂安全级仪控系统(Digital Instrumentation and Control System,DCS)的重要部件,鉴定试验要求在试验应力下对其进行操作,并测试其功能和性能。核电DCS设备鉴定的部分试验条件十分严酷,很难在试验中对设备进行操作。之前采用的方法是测试人员穿防护设备进入温箱等严酷环境进行测试,既影响了试验效率,又可能对测试人员造成健康上的损害。本文首先分析了鉴定试验的环境特点;然后提出采用步进电机进行精确控制的方法,实现对人机接口设备的自动操作;最后结合鉴定试验特点,给出对机械臂的防护措施。基于该测试方法集成的自动测试装置已投入鉴定试验活动中,并实现了远程全自动操作。