Расчетная оценка безотказности многоканального преобразователя напряжения c ротацией силовых каналов
Dependability of power electronics products designed for power supply of electronic equipment, largely determine its dependability, because failure of the power supply system, as a rule, leads to failure of the equipment as a whole. Therefore, the secondary power supply must be highly reliable. To ensure the required dependability of power supplies, various methods of their construction and redundancy are used. Early stages of design determine the dependability that will be implemented in the manufacture and maintained during operation. At these stages, dependability prediction are of paramount importance.
The complexity of power supply architectures and the use of redundancy in them leads to the complexity of analytical of their dependability prediction and requires the involvement of highly qualified specialists. The use of specialized software that implements simulation modeling in the calculation of structurally complex power supplies also causes certain difficulties associated with the construction of formal models and their verification. Therefore, the improvement of analytical methods to obtain estimates of the dependability of power sources is currently being given a lot of attention.
At present, one of the promising directions of improving the reliability of voltage converters is the use of backbone-modular architecture, mixed redundancy and rotation of the major and redundant power channels. For such a converter, an analytical method for calculating the lower and upper estimate of the reliability function is proposed, which is based on the use of a standardized model for the group "sliding loaded redundancy". It is shown that the channel rotation as the reliability characteristics of the channels can be used cyclic failure rate.
In contrast to the known, the developed method allows to obtain these estimates as a function of time and taking into account the failure rates of the converter channels not only in the operating mode, but also in the standby mode.
An example of calculating the limits of the reliability function of the converter by the proposed method is given, and to confirm the results of the calculation of the same example by simulation. In addition, it is shown that the reduction of the full rotation cycle of the channels increases the uniformity of the resource consumption by the channels with an "absolutely reliable" switch and does not affect the reliability of the converter, and the "unreliable" switch leads to a decrease in reliability.
For the effective functioning of the onboard avionics, require sealing. Gasket failure rate directly affects the probability of successful operation of the device in a sealed condition. Gasket failure rate, in turn, depends on many factors.
The considered model of the failure rate of CMOS VHSIC design proposed in the article Piskun G.A., Alekseev V.F., "Improvement of mathematical models calculating of CMOS VLSIC taking into account features of impact of electrostatic discharge", published in the first issue of the journal "Technologies of electromagnetic compatibility" for the year 2016. It is shown that the authors claim that this model "...will more accurately assess the reliability of CMOS VHSIC design" is fundamentally flawed and its application will inevitably lead to inadequate results. Alternatively, the proposed model of the failure rate of CMOS VHSIC design, which also allows to take into account the views of ESD, but based on the use of resistance characteristics of CMOS VHSIC to the effects of ESD.
The article considers the questions assessing the reliability of mechanical components used in the electronic equipment in the early stages of design. The calculations of failure rates springs shock absorbers according to various methods. It is shown that the use of models failure rates of mechanical elements, taking into account the peculiarities of their structural and technological performance, not only allows us to solve the problem of calculating, but also to ensure the required level of reliability and mechanical components, and containing electronic equipment.
The current period of creation of the electronic equipment of a responsible and special purpose is characterized by universal introduction of the Quality Management Systems at the enterprises developers and producers of electronic equipment. Quality Management System and its component – Dependability Management System are aimed at providing the guaranteed level of indicators of quality (including and dependability indicators).
In the reliability prediction method recommended by the Russian standards influence of procedures of Dependability Management System is considered with the help of «Coefficient Quality Production Equipment» (КА). This coefficient considers and reflects an average difference in failure rate of elements in the equipment developed and manufactured on requirements of various standard documentation (1 – for a complex of the standards «Moroz …» or 0,2 – for the situation «RK-…»).
However, such approach to forecasting reliability prediction of electronic equipment at the early design stages, based on use of average statistical data rather approximate. It doesn’t consider neither features of Dependability Management System of the concrete enterprise, nor completeness of the Support Reliability Program when developing.
Therefore more adequate approach to an assessment of value of the coefficient КА realized in methodology 217PlusTM is represented. According to this methodology when forecasting value of the coefficient КА are used not only statistical estimates, but also an expert assessment of Dependability Management System effectiveness during the developing and production of the equipment.
The article discusses all the features of application of methodology 217PlusTM for an assessment of the coefficient КА: mathematical model of multiple-factor coefficient of quality of production, analysis of influence of its components on the general level and functional model of reliability prediction process.
Consider the dependence of coefficient of quality equipment from a variety of factors and its influence on the reliability of modern software and hardware systems. In terms of reliability software and hardware systems are serial connection elements. For them, the prediction model of the failure rate in the mode of operation depends on the technical means failure rate, the Software Tool failure rate and coefficient of quality equipment.
DepCoS – RELCOMEX is an annual series of conferences organized by Wrocław University of Technology to promote a comprehensive approach to evaluation of system performability which is now commonly called dependability. In contrast to classic analyses which were concentrated on reliability of technical resources and structures built from them, dependability is based on multi-disciplinary approach to theory, technology, and maintenance of a system considered to be a multifaceted amalgamation of technical, information, organization, software and human (users, administrators, supervisors, etc.) resources. Diversity of processes being realized (data processing, system management, system monitoring, etc.), their concurrency and their reliance on in-system intelligence often severely impedes construction of strict mathematical models and calls for application of intelligent and soft computing methods.
This book presents the proceedings of the Ninth International Conference on Dependability and Complex Systems DepCoS-RELCOMEX, which took place in Brunów Palace, Poland, from 30th June to 4th July, 2014. The articles selected for this volume illustrate the variety of topics that must be included in system dependability analysis: tools, methodologies and standards for modelling, design and simulation of the systems, security and confidentiality in information processing, specific issues of heterogeneous, today often wireless, computer networks, or management of transportation networks.
Mathematical models of failure rate of refusals the elements applied in calculations of reliability of the onboard electronic equipment are considered. Possibility of application the models given in foreign standards, for forecasting of reliability of completing elements is shown.
DepCos-RELCOMEX is an annual series of conferences organized by the Institute of Computer Engineering, Control and Robotics (CECR), Wroclaw University of Technology, since 2006.
Contemporary technical systems are integrated unities of technical, information, organization, software and human resources. Diversity of the processes being realized in the system, their concurrency and their reliance on in-system intelligence significantly impedes construction of strict mathematical models and calls for application of intelligent and soft computing methods.
The submissions included in this volume illustrate variety of problems that need to be explored in the dependability analysis: methodologies and practical tools for modelling, design and simulation of the systems, security and confidentiality in information processing, specific issues of heterogeneous, today often wireless, computer networks, or management of transportation networks.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.