scholarly journals A Review of Prognostics and Health Management Applications in Nuclear Power Plants

Author(s):  
Jamie Coble ◽  
Pradeep Ramuhalli ◽  
Leonard Bond ◽  
J. Wesley Hines ◽  
Belle Upadhyaya

The US operating fleet of light water reactors (LWRs) is currently undergoing life extensions from the original 40- year license to 60 years of operation. In the US, 74 reactors have been approved for the first round license extension, and 19 additional applications are currently under review. Safe and economic operation of these plants beyond 60 years is now being considered in anticipation of a second round of license extensions to 80 years of operation. Greater situational awareness of key systems, structures, and components (SSCs) can provide the technical basis for extending the life of SSCs beyond the original design life and supports improvements in both safety and economics by supporting optimized maintenance planning and power uprates. These issues are not specific to the aging LWRs; future reactors (including Generation III+ LWRs, advanced reactors, small modular reactors, and fast reactors) can benefit from the same situational awareness. In fact, many small modular reactor (SMR) and advanced reactor designs have increased operating cycles (typically four years up to forty years), which reduce the opportunities for inspection and maintenance at frequent, scheduled outages. Understanding of the current condition of key equipment and the expected evolution of degradation during the next operating cycle allows for targeted inspection and maintenance activities. This article reviews the state of the art and the state of practice of prognostics and health management (PHM) for nuclear power systems. Key research needs and technical gaps are highlighted that must be addressed in order to fully realize the benefits of PHM in nuclear facilities.

2021 ◽  
Vol 9 ◽  
Author(s):  
Xingang Zhao ◽  
Junyung Kim ◽  
Kyle Warns ◽  
Xinyan Wang ◽  
Pradeep Ramuhalli ◽  
...  

In a carbon-constrained world, future uses of nuclear power technologies can contribute to climate change mitigation as the installed electricity generating capacity and range of applications could be much greater and more diverse than with the current plants. To preserve the nuclear industry competitiveness in the global energy market, prognostics and health management (PHM) of plant assets is expected to be important for supporting and sustaining improvements in the economics associated with operating nuclear power plants (NPPs) while maintaining their high availability. Of interest are long-term operation of the legacy fleet to 80 years through subsequent license renewals and economic operation of new builds of either light water reactors or advanced reactor designs. Recent advances in data-driven analysis methods—largely represented by those in artificial intelligence and machine learning—have enhanced applications ranging from robust anomaly detection to automated control and autonomous operation of complex systems. The NPP equipment PHM is one area where the application of these algorithmic advances can significantly improve the ability to perform asset management. This paper provides an updated method-centric review of the full PHM suite in NPPs focusing on data-driven methods and advances since the last major survey article was published in 2015. The main approaches and the state of practice are described, including those for the tasks of data acquisition, condition monitoring, diagnostics, prognostics, and planning and decision-making. Research advances in non-nuclear power applications are also included to assess findings that may be applicable to the nuclear industry, along with the opportunities and challenges when adapting these developments to NPPs. Finally, this paper identifies key research needs in regard to data availability and quality, verification and validation, and uncertainty quantification.


Author(s):  
P.V. Varde ◽  
Michael G. Pecht

There is a growing trend in applying a prognostics and health management approach to engineering systems in general and space and aviation systems in particular. This paper reviews the role of prognostics and health management approach in support of integrated risk-based applications to nuclear power plants, like risk-based in-service inspection, technical specification optimization, maintenance optimization, etc. The review involves a survey of the state-of-art technologies in prognostics and health management and an exploration of its role in support of integrated risk-based engineering and how the technology can be adopted to realize enhanced safety and operational performance. An integrated risk-based engineering framework for nuclear power plants has been proposed, where probabilistic risk assessment plays the role of identification, prioritization and optimization of systems, structures, and components, while deterministic assessment is performed using a prognostics and health management approach. Keeping in view the requirements of structural reliability assessment, the paper also proposes essential features of a ‘Mechanics-of-Failure’ approach in support of integrated risk-based engineering. The performance criteria used in prognostics and health management has been adopted to meet requirements of risk-based applications.


2012 ◽  
Author(s):  
Jamie B. Coble ◽  
Pradeep Ramuhalli ◽  
Leonard J. Bond ◽  
Wes Hines ◽  
Belle Upadhyaya

2019 ◽  
Vol 11 (4) ◽  
pp. 305-310
Author(s):  
R. Z. Aminov ◽  
E. Yu. Burdenkova ◽  
A. V. Portyankin

A method is presented for estimating the possible annual risk that a hydrogen superstructure at a nuclear power plant (NPP) may have in the production of explosive hydrogen. With the observance of safety rules in terms of receiving, storing, transporting and using hydrogen, it is possible to minimize the occurrence of fi re and explosion hazard situations on the hydrogen superstructure. Scheduled repair and overhauls with all diagnostics reduce emergencies and equipment failures in the same way. However, there is a likelihood for the equipment to be found in an abnormal state (breakdown, fi re and explosion) as a result of hydrogen leaks. Depressurization of equipment with leakage of explosive hydrogen in enclosed spaces concurrently with adverse attendant factors may lead to the destruction of the electrolysis plant due to fi re and explosion. With the help of the state graph, the probabilities of a failure of electrolysis equipment because of unplanned breakdowns and possible fi res or explosions indoors due to depressurization of equipment are estimated. To this effect, possible scenarios of breakdowns of the electrolyzer in one and two workshops are considered. In the calculations of the state graph, a system of linear equations was composed for steady-state values only. The calculations have shown that for a configuration involving two electrolysis plants, the possible annual risk would increase. Minimizing the annual risk can be achieved through boosting the capacity of the electrolysis plant still in operation by increasing its productivity in hydrogen and oxygen. The effect will only be achieved if the cost of electricity from nuclear power plants is kept within 0.81 rubles/(kW·h) with a peak electricity tariff at 3.5 rubles/(kW·h).


Author(s):  
William D. Rezak

One of America’s best kept secrets is the success of its nuclear electric power industry. This paper presents data which support the construction and operating successes enjoyed by energy companies that operate nuclear power plants in the US. The result—the US nuclear industry is alive and well. Perhaps it’s time to start anew the building of nuclear power plants. Let’s take the wraps off the major successes achieved in the nuclear power industry. Over 20% of the electricity generated in the United States comes from nuclear power plants. An adequate, reliable supply of reasonably priced electric energy is not a consequence of an expanding economy and gross national product; it is an absolute necessity before such expansion can occur. It is hard to imagine any aspect of our business or personal lives not, in some way, dependent upon electricity. All over the world (in 34 countries) nuclear power is a low-cost, secure, safe, dependable, and environmentally friendly form of electric power generation. Nuclear plants in these countries are built in six to eight years using technology developed in the US, with good performance and safety records. This treatise addresses the success experienced by the US nuclear industry over the last 40 years, and makes the case that this reliable, cost-competitive source of electric power can help support the economic engine of the country and help prevent experiences like the recent crisis in California. Traditionally, the evaluation of electric power generation facility performance has focused on the ability of plants to produce at design capacity for high percentages of the time. Successful operation of nuclear facilities is determined by examining capacity or load factors. Load factor is the percentage of design generating capacity that a power plant actually produces over the course of a year’s operation. This paper makes the case that these operating performance indicators warrant renewed consideration of the nuclear option. Usage of electricity in the US now approaches total generating capacity. The Nuclear Regulatory Commission has pre-approved construction and operating licenses for several nuclear plant designs. State public service commissions are beginning to understand that dramatic reform is required. The economy is recovering and inflation is minimal. It’s time, once more, to turn to the safe, reliable, environmentally friendly nuclear power alternative.


2018 ◽  
Vol 183 (4) ◽  
pp. 503-513 ◽  
Author(s):  
Tae Young Kong ◽  
Gamal Akabani ◽  
John W Poston

Abstract One of the most important issues in the nuclear power industry is the implementation of the 2007 Recommendations of the International Commission on Radiological Protection (ICRP) published in ICRP Publication 103. These recommendations include the implementation of the concept of dose constraints for occupationally exposed workers at nuclear power plants (NPPs). When considering these changes from a cost–benefit standpoint, the implementation of dose constraints is still highly controversial. This study analysed annual occupational dose distributions to determine whether a dose constraint is needed for occupationally exposed workers at the US NPPs. Results of the analysis showed that the use of dose constraints had no positive impact on radiation safety of workers at NPPs in the USA. In fact, it appears that the implementation of dose constraints will impose an unnecessary regulatory burden on licensees. Based on these results, implementation of dose constraints is not recommended.


Author(s):  
Juyoul Kim ◽  
Batbuyan Tseren

Assessing workers’ safety and health during the decommissioning of nuclear power plants (NPPs) is an important procedure in terms of occupational radiation exposure (ORE). Optimizing the radiation exposure through the “As Low As Reasonably Achievable (ALARA)” principle is a very important procedure in the phase of nuclear decommissioning. Using the VISIPLAN 3D ALARA planning tool, this study aimed at assessing the radiological doses to workers during the dismantling of the reactor pressure vessel (RPV) at Kori NPP unit 1. Fragmentation and segmentation cutting processes were applied to cut the primary component. Using a simulation function in VISIPLAN, the external exposure doses were calculated for each work operation. Fragmentation involved 18 operations, whereas segmentation comprised 32 operations for each fragment. Six operations were additionally performed for both hot and cold legs of the RPV. The operations were conducted based on the radioactive waste drum’s dimensions. The results in this study indicated that the collective doses decreased as the components were cut into smaller segments. The fragmentation process showed a relatively higher collective dose compared to the segmentation operation. The active part of the RPV significantly contributed to the exposure dose and thus the shielding of workers and reduced working hours need to be considered. It was found that 60Co contained in the stainless steel of the reactor vessel greatly contributed to the dose as an activation material. The sensitivity analysis, which was conducted for different cutting methods, showed that laser cutting took a much longer time than plasma cutting and contributed higher doses to the workers. This study will be helpful in carrying out the occupational safety and health management of decommissioning workers at Kori NPP unit 1 in the near future.


1998 ◽  
Vol 30 (2) ◽  
pp. 145-151
Author(s):  
I. A. Vystavkin ◽  
V. M. Torop ◽  
O. V. Biryukov

Sign in / Sign up

Export Citation Format

Share Document