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Hydropower, wind power, and photovoltaic power generation are the most common clean energy sources and are important ways to achieve “carbon neutrality” and “carbon peak”. With the adjustment of China’s energy structure, wind power and photovoltaic power generation have entered the peak period of development, but the above two forms of power generation have a certain degree of instability, which has increased the risk of safe and stable operation of the power grid. In contrast, hydroelectric power generation has good stability, and giving full play to the excellent peak and frequency modulation functions of hydro-generator sets is of great significance to ensuring the safe and stable operation of the power grid. This requires the hydro-generator unit to have good reliability during the service period. Through the evaluation of the unit’s health status, the unit’s health status can be predicted, and the maintenance strategy can be given to eliminate the fault in the budding state. This article summarizes the health status assessment methods of hydro-turbine generator sets, and puts forward five health status levels: “healthy”, “good”, “attention”, “abnormal” and “dangerous”. This paper has carried out a quantitative calculation on the health status of a certain hydraulic turbine. The results show that the degree of health of the turbine is “healthy”, “good”, “attention”, “abnormal” and “dangerous” respectively and the degrees are 0.065, 0.632, 0.279, 0.024, 0. According to the principle of maximum membership, it can be judged that the turbine is in “good” status. The evaluation result is consistent with the actual operation of the unit, indicating that the evaluation method studied in this paper has a certain practicability and can provide scientific guidance for the health evaluation of the hydroelectric generating unit.

International audience; This study is aimed at increasing the performance and reliability of silicon-based heterojunction solar cells with advanced methods. This is achieved by a numerical electro-optical modeling and reliability analysis for such solar cells correlated with experimental analysis of the Cu2O absorber layer. It yields the optimization of a silicon tandem heterojunction solar cell based on a ZnO/Cu2O subcell and a c-Si bottom subcell using electro-optical numerical modeling. The buffer layer affinity and mobility together with a low conduction band offset for the heterojunction are discussed, as well as spectral properties of the device model. Experimental research of N-doped Cu2O thin films was dedicated to two main activities: (1) fabrication of specific samples by DC magnetron sputtering and (2) detailed characterization of the analyzed samples. This last investigation was based on advanced techniques: morphological (scanning electron microscopy—SEM and atomic force microscopy—AFM), structural (X-ray diffraction—XRD), and optical (spectroscopic ellipsometry—SE and Fourier-transform infrared spectroscopy—FTIR). This approach qualified the heterojunction solar cell based on cuprous oxide with nitrogen as an attractive candidate for high-performance solar devices. A reliability analysis based on Weibull statistical distribution establishes the degradation degree and failure rate of the studied solar cells under stress and under standard conditions. View Full-Text

The purpose of the article is to improve the integral criterion of assessment of environmental condition of the territory with the index of its environmental reserve level. Originality of the achieved result is in application of the indicators characterizing ecosystem degradation process for quantitative description of the territory’ environmental response on negative impact factors influence. The advantage of the proposed integral criterion is in formalized representation of environmental reserve level indexes. It allows to apply achieved values for assessment of environmental condition of the territory in simulation quantitative experiments for investigation of the object states concerning to occurrence of extreme situations of different kind at the wastes storage place. Usage of the improved environmental reserve criterion allows forming of complex assessment of environmental condition of the territory in short-term perspective, and at the same time to forecast degradation process development in it., Усовершенствован интегральный критерий оценивания экологического состояния территории по показателю уровня ее экологического резерва. Новизна полученного результата состоит в использовании в качестве откликов окружающей среды на влияние факторов негативного воздействия величин, характеризующих процессы деградации в экосистемах. Формализованное представление показателей уровня экологического резерва предоставляет возможность использовать их для оценивания экологического состояния территории в имитационных числовых экспериментах, касающихся исследования состояний места хранения отходов, которые соответствуют реализации в нем чрезвычайных ситуаций различного происхождения. Применение усовершенствованного критерия экологического резерва позволяет формировать комплексную оценку экологического состояния территории в краткосрочной перспективе, а также прогнозировать развитие процесса деградации в ней., Вдосконалено інтегральний критерій оцінювання екологічного стану території за показником рівня її екологічного резерву. Новизна отриманого результату полягає у використанні в якості відгуків довкілля на дію факторів негативного впливу величин, які характеризують деградаційні процеси в екосистемах. Формалізоване представлення показників рівня екологічного резерву надає можливість використовувати їх для оцінювання екологічного стану території у імітаційних числових експериментах з дослідження станів місця зберігання відходів, що відповідають реалізації в ньому надзвичайних ситуацій різного походження. Використання вдосконаленого критерію екологічного резерву дозволяє формувати комплексну оцінку екологічного стану території у короткотерміновій перспективі, а також надавати прогноз розвитку процесу деградації в ній.

This study determines the early deterioration condition of critical components for a wind turbine generator system (WTGS). Due to the uncertainty nature of the fluctuation and intermittence of wind, early deterioration condition evaluation poses a challenge to the traditional vibration-based condition monitoring methods. Considering the its thermal inertia and strong anti-interference capacity, temperature characteristic parameters as a deterioration indication cannot be adequately disturbed by the uncontrollable noise and uncertainty nature of wind. This paper provides a probability evaluation method of early deterioration condition for critical components based only on temperature characteristic parameters. First, the dynamic threshold of deterioration degree function was proposed by analyzing the operational data between temperature and rotor speed. Second, a probability evaluation method of early deterioration condition was presented. Finally, two cases showed the validity of the proposed probability evaluation method in detecting early deterioration condition and in tracking their further deterioration for the critical components.

This document describes processing basic measurement signals, which were used in test sequence with different coders. The determination of degradation degree of these signals and the elimination of these coders influences on these signals was the aim of this paper. At the end of this paper the test sequence is defined. We can use this sequence for intrusive measurement VTQoS in the networks, using the coders with lower transfer rate.