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reliability evaluation of Machine Center Components Based on Cascading Failure Analysis

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 933-942页

作者： Ying-Zhi Zhang Jin-Tong Liu Gui-Xiang Shen Zhe Long Shu-Guang Sun College of Mechanical Science and Engineering Jilin University College of Management Science and Engineering Shandong Normal University

In order to rectify the problems that the com- ponent reliability model exhibits deviation, and the evalu- ation result is low due to the overlook of failure propagation in traditional reliability evaluation of machine center components, a new reliability evaluation method based on cascading failure analysis and the failure influ- enced degree assessment is proposed. A direct graph model of cascading failure among components is established according to cascading failure mechanism analysis and graph theory. The failure influenced degrees of the system components are assessed by the adjacency matrix and its transposition, combined with the Pagerank algorithm. Based on the comprehensive failure probability function and total probability formula, the inherent failure proba- bility function is determined to realize the reliability evaluation of the system components. Finally, the method is applied to a machine center, it shows the following： 1） The reliability evaluation values of the proposed method are at least 2.5% higher than those of the traditional method; 2） The difference between the comprehensive and inherent reliability of the system component presents a positive correlation with the failure influenced degree ofthe system component, which provides a theoretical basis for reliability allocation of machine center system.

关键词： s Cascading failure Machine centercomponents reliability evaluation Pagerank algorithmInfluenced degree

reliability evaluation of avionics system with imperfect fault coverage and propagated failure mechanisms

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Chinese Journal of Aeronautics 2020年第12期33卷 3437-3446页

作者： Ying CHEN Song YANG Rui KANG Science and Technology on reliability and Environmental Engineering Laboratory Beihang UniversityBeijing 100083China

Fault tolerance designs are essential techniques for systems that require high levels of reliability,such as aircraft or spacecraft control *** Fault Coverage(IFC)may lead to the failure of a system or subsystem even with adequate *** studies of IFC mostly concentrated on evaluating Coverage Factor(CF),whereas the system failure behaviors with IFC have rarely been *** that occur in low-layer may be covered by ***,if the coverage is imperfect,uncovered failure will have functional and physical impact on the system *** this thesis,the failure behavior and reliability of IFC of multi-layer systems are studied and a Binary Decision Diagram(BDD)-based modeling and simulation method are proposed to evaluate system *** a case,the failure behavior of an aero engine electronic controller with IFC is *** results show that the IFC may impact system behavior without taking the IFC into account,the system maintenance intervals may reduce,and thus the maintenance costs will increase.

关键词： Acceleration Binary Decision Diagram(BDD) Failure mechanism Imperfect Fault Coverage Multi-layer system reliability evaluation

reliability evaluation of Wind Power Converter Under Fault-tolerant Control Scheme with Quantification of Temperature and Humidity Effects

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Journal of Modern Power Systems and Clean Energy 2023年第5期11卷 1700-1710页

作者： Xueying Yu Bo Hu Kaigui Xie Changzheng Shao Yunjie Bai Wenyuan Li Jinfeng Ding State Key Laboratory of Power Transmission Equipment and System Security Chongqing UniversityChongqing 400030China

Wind power converter(WPC)is a key part of a wind power unit which delivers electric energy to power *** of a large number of semiconductors,WPC has a high failure *** paper proposes a method to accurately evaluate the reliability of WPC,which is crucial for the design and maintenance of wind ***,the index of effective temperature(ET)is presented to quantify the effects of temperature and humidity on the semiconductor operation.A novel method is proposed to evaluate the lifetime and calculate the aging failure rates of the semiconductors considering the fluctuations of ***,the failure mode and effect analysis(FMEA)of WPC is investigated based on the topology and control *** conventional two-state reliability model of the WPC is extended to the multi-state reliability model where the partial working state under the fault-tolerant control scheme is ***,a reliability evaluation framework is established to calculate the parameters of the WPC reliability model considering the variable failure rates and repair activities of *** studies are designed to verfify the proposed method using a practical wind turbine.

关键词： Effective temperature(ET) fault-tolerant control scheme humidity reliability evaluation wind power converter(WPC)

reliability evaluation method and algorithm for electromechanical product

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Journal of Central South University 2014年第10期21卷 3753-3761页

作者：刘勇军范晋伟李云 College of Electromechanical Engineering and Applied Electronics Technology Beijing University of Technology

The reliability of electromechanical product is usually determined by the fault number and working time traditionally. The shortcoming of this method is that the product must be in service. To design and enhance the reliability of the electromechanical product, the reliability evaluation method must be feasible and correct. reliability evaluation method and algorithm were proposed. The reliability of product can be calculated by the reliability of subsystems which can be gained by experiment or historical data. The reliability of the machining center was evaluated by the method and algorithm as one example. The calculation result shows that the solution accuracy of mean time between failures is 97.4% calculated by the method proposed in this article compared by the traditional method. The method and algorithm can be used to evaluate the reliability of electromechanical product before it is in service.

关键词： reliability evaluation mean time between failures probability density function electromechanical product

reliability evaluation of All-User Terminals in LEO Satellite Communication Network Based on Modular Reduction

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China Communications 2022年第2期19卷 235-246页

作者： Yangyang Du Sifeng Liu Zhigeng Fang Su Gao College of Economics and Management Nanjing University of Aeronautics&AstronauticsNanjing 211106Jiangsu ProvinceChina Institute of Telecommunication Satellite China Academy of Space Technology(CAST) Beijing 100094China

LEO satellite communication network has a large number of satellites distributed in low orbits,which leads to multiple coverage of many areas on the *** is hard work to describe and evaluate the reliability of LEO satellite communication *** solve this problem,the reliability of all-user terminals in LEO satellite communication network is defined,and the corresponding reliability evaluation method is proposed in the *** to the large scale of the interstellar network,a modular reduction algorithm using the modular network instead of the original network for state decomposition is proposed in this *** study shows that the calculation time of the proposed method is equivalent to 6.28%of the original state space decomposition *** this basis,the reliability of LEO satellite communication network is further *** is found that the reliability of LEO satellite network was more sensitive to the reliability of Inter-Satellite link and the satisfaction of global coverage in the early stage,and it is more sensitive to the reliability of the satellite in the later *** satellite-ground link has a relatively constant impact on of LEO satellite network.

关键词： reliability evaluation LEO satellite communication network modular approach full probability formula all-user terminals

reliability evaluation of tidal and wind power generation system with battery energy storage

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Journal of Modern Power Systems and Clean Energy 2016年第4期4卷 636-647页

作者： Mingjun LIU Wenyuan LI Juan YU Zhouyang REN Ruilin XU State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400030China Chongqing Electric Power Research Institute Chongqing 401123China

This paper presents a method for reliability evaluation of a hybrid generation system of wind and tidal powers with battery energy *** a system may widely exist in coastal areas and islands in the future.A chronological multiple state probability model of tidal power generation system(TPGS)considering both forced outage rate(FOR)of the TPGS and random nature of tidal current speed is *** the evaluation of FORs of TPGS and WPGS(wind power generation system),the delivered power related failure rates of power electronic converters for TPGS and WPGS are considered.A chronological power output model of battery energy storage system(BESS)is derived.A hybrid system of tidal and wind generation powers with a BESS is used to demonstrate the effectiveness of the presented *** case studies,the effects of various parameters on the system reliability are investigated.

关键词： Generation system Tidal power generation Wind power generation Battery energy storage reliability evaluation

reliability evaluation Method Based on Double Beta Prior Distribution for the Pyrotechnic Device

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Journal of Shanghai Jiaotong university(Science) 2019年第5期24卷 622-627页

作者： CHENG Li YANG Yuanyuan MU Huina YANG Xiaoyu LI Li WEN Yuquan State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

On the basis of the Bayesian principle, a method of selecting the double beta distribution as a priori distribution is proposed for the system reliability evaluation when the available field test samples are small for pyrotechnic device. Under the condition of different field and historical data, the mean square error(MSE) and coverage ratio(CR) of the reliability evaluation are compared by numerical simulation when the conjugate distribution and uniform distribution are selected as the priori distribution. Finally, the rationality and engineering applicability of the proposed method are verified through an example of the reliability evaluation of a typical pyrotechnic device.

关键词： double beta distribution Bayesian principle reliability evaluation

reliability evaluation of Two-Phase Degradation Process with a Fuzzy Change-Point

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 867-872页

作者： LIU Kai DANG Wei ZOU Tianji LÜCongmin LI Peng ZHANG Haitao Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing 100094China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China

For some products,degradation mechanisms change during testing,and therefore,their degradation patterns vary at different points in time;these points are called *** to the limitation of measurement costs,time intervals for degradation measurements are usually very long,and thus,the value of change-points cannot be ***,a certain degradation measurement is selected as the change-point in a two-phase degradation *** to the tendency of the two-phase degradation process,the change-point is probably located in the interval between two neighboring degradation measurements,and it is a fuzzy *** imprecision of the change-point may lead to the incorrect product’s reliability evaluation *** this paper,based on the fuzzy theory,a two-phase degradation model with a fuzzy change-point and a statistical analysis method are ***,a two-phase Wiener degradation model is developed according to the membership function of the ***,the reliability evaluation is carried out using maximum likelihood estimation and a fuzzy simulation ***,the proposed methodology is verified via a case *** results of the study show that the proposed methodology can achieve more believable reliability evaluation results compared with those of the conventional approach.

关键词： two-phase degradation Wiener process fuzzy change-point membership function reliability evaluation statistical analysis

reliability evaluation on CNC lathes based on the modified L-M method

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Journal of Harbin Institute of Technology(New Series) 2009年第5期16卷 665-668页

作者：于捷石耀霖申桂香贾亚洲 Laboratory of Computational Geodynamics Graduate University of Chinese Academy of Sciences Mechanical Engineering College Changchun University Mechanical Engineering College Jilin University

Equivalent ways commonly used in engineering works are not effective to estimate the reliability of tandem system based on L-M method. One modified L-M method is an important means to estimate the reliability of CNC lathes. A method of using two named confidence limits for the estimation is put forward. Fitting resuits of the sub-systems of CNC machine tools are estimated. And the scattered level of confidence limits facing the reliability matrix of sub-systems can be clearly seen.

关键词： L-M method CNC lathes reliability evaluation confidence limits scattered level