scholarly journals A Comprehensive Evaluation on Types of Microcracks and Possible Effects on Power Degradation in Photovoltaic Solar Panels

2020 ◽  
Vol 12 (16) ◽  
pp. 6416
Author(s):  
Mathhar Bdour ◽  
Zakariya Dalala ◽  
Mohammad Al-Addous ◽  
Ashraf Radaideh ◽  
Aseel Al-Sadi
Keyword(s):  
Power Loss ◽  
Power Plants ◽  
Comprehensive Evaluation ◽  
Decision Makers ◽  
Solar Panels ◽  
Pv Systems ◽  
Competitive Prices ◽  
Different Shapes ◽  
Operation Phase

Photovoltaic (PV) panels installation has become one of the major technologies used for energy production worldwide. Knowledge and competitive prices are the main reasons for the spread usage and expanded exploiting of PV systems. Accordingly, this creates several challenges for manufacturers and customers, mainly, the quality of PV panels to withstand environmental conditions during service lifetime. Hence, the quality of PV panels is a vital aspect. By thinking of PV power plants, it appears that some factors should be considered, like the developing microcracks (µcracks). An issue like that increases the chances of having power loss during the operation phase. Notably, µcracks develop in different shapes and orientations; the variation depends on what causes them. This study is a presentation and summary of data collected from different projects in Jordan to describe the effect of each µcracks shape on power loss, aiming to give decision makers an indication to decide whether to replace the faulty panels or not, depending on their own conditions and projects sizes. Hence, in this study, it was found that the µcracks have impacted power loss differently and recorded power reduction of percentages of 0.82–3.21% for poly-crystalline technology. Variation in power degradation depends on the module situation; whether it is stocked in facility or operated on-site. In the mono-crystalline technology case, the power losses varied between 0.55% and 0.9%, with the exception of some samples from both technologies that have effects other than microcracks, which affected power severely. Furthermore, a general overview is provided for µcracks before installation.

scholarly journals Changes of Insulation Properties of Photovoltaic Cables Caused by Ageing Treatment

2020 ◽  
Vol 6 (1) ◽  
pp. 6-9 ◽  
Author(s):  
Juraj Packa ◽  
Vladimir Kujan ◽  
Daniel Štrkula ◽  
Vladimír Šály ◽  
Milan Perný
Keyword(s):  
Power Plants ◽  
Real Life ◽  
Life Time ◽  
Operating Conditions ◽  
Solar Panels ◽  
Font Size ◽  
Long Term Stability ◽  
Cable Systems

<span style="font-family: 'Times New Roman',serif; font-size: 10pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">An important part of the photovoltaic power plants are cable systems. The dielectric properties of cables, reliability and durability depend on quality of production processes, operating conditions and degradation factors, as well. Expected lifetime of cable systems is more than 20-30 years in general. Their failure free operation and long-term stability of properties has a direct impact on the economic return of the investments. According to our experiences the tests in compliance with valid standards are not adequate to verify real life time during operation. Photovoltaic cables intended for use in outdoor applications for the connection between the solar panels and possible connection between panels and inverter were chosen for our experiments. <span style="-ms-layout-grid-mode: line;">The changes </span>of insulation resistance and breakdown voltage caused by some degradation factors, mainly water, are presented. This research was inspired by real failure in operation.</span>

scholarly journals PERANCANGAN INVERTER SATU FASA OFF-GRID MENGGUNAKAN DSPIC30F4011 DENGAN KONTROL ARUS METODE PROPORTIONAL RESONANT

TRANSIENT ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 753
Author(s):  
Segal Mancini Suroso ◽  
Iwan Setiawan ◽  
Bambang Winardi
Keyword(s):  
Power Plants ◽  
Harmonic Distortion ◽  
Current Control ◽  
System Response ◽  
Output Current ◽  
Current Output ◽  
Current Harmonics ◽  
Pv Systems ◽  
Bridge Type

The availability of fossil as fuel in conventional power plants is running low. This causes the use of renewable energy such as photovoltaic (PV) technology becomes very important. PV systems required inverters for converting DC voltage into AC voltage, where the quality of the inverter output current is very influential on the quality of power. Therefore, it is necessary to control the inverter current output which serves to improve the system response and minimize the current harmonics. In this research, a H-Bridge type of one phase Inverter is designed using 16-bit DSPIC30F4011 microcontroller with current control proportional resonant method. The inverter output current is fedback by the ACS712-05B current sensor. The test is carried out with the reference current range of 1 - 3 A on the load variation 7 Ω and 12 Ω. The test results show the actual current waveform of the inverter output is able to follow the reference current changes. Inductor value that not suitable and the effect of switching cause the ripple is still happening. The higher the output voltage of the inverter will result in the total current harmonic distortion becoming smaller.

Operation of Voltage Reactive Power Control Devices based on Cooperation between Two-Voltage Class Transmission Network with PV Systems to Reduce Power Loss

2020 ◽  
Vol 140 (6) ◽  
pp. 484-494
Author(s):  
Akihisa Kaneko ◽  
Shinya Yoshizawa ◽  
Yasuhiro Hayashi ◽  
Shuhei Sugimura ◽  
Yoshinobu Ueda ◽  
...  
Keyword(s):  
Power Control ◽  
Power Loss ◽  
Reactive Power ◽  
Transmission Network ◽  
Reactive Power Control ◽  
Pv Systems ◽  
Control Devices

Justification for Unscheduled Maintenance of Solar Panels Used as a Power Supply for Sprinkler Machines

2020 ◽  
Vol 67 (1) ◽  
pp. 16-21
Author(s):  
Sergey M. Bakirov ◽  
Sergey S. Eliseev
Keyword(s):  
Power Supply ◽  
Power Loss ◽  
Renewable Energy Sources ◽  
Operating Mode ◽  
Dust Storms ◽  
Research Purpose ◽  
Solar Panels ◽  
Solar Module ◽  
Empirical Observation ◽  
Modern Level

The modern level of agriculture is described by the introduction of renewable energy sources. New generation sprinkler machines are being put into production, in the power system of which solar panels are used. One of the factors that negatively affect the performance of solar cells in an open field is their dusting, which is formed as a result of dust storms and wind. Cleaning of the battery panels is carried out in various ways: manual, semi-automatic and automatic. Dust cleaning is included in maintenance. (Research purpose) The research purpose is to determine the conditions for performing the maintenance, which consists in cleaning solar panels in the field. (Materials and methods) Theoretical (analysis, hypothesis design), empirical (observation, testing), experimental (ascertaining experiment) methods has been used during research. (Results and discussion) The article describes an introduced parameter for estimating the level of dusting. The power loss indicator shows the ratio of the power of the dusted module to the power of the clean module. Unscheduled maintenance is affected by the distance of the solar module from the repair point, the power of the solar module, the loss from dusting, the frequency of maintenance and cost indicators. (Conclusions) It has been found the dependence of maintenance period of the solar module of the sprinkler machine on the distance to the sprinkler machine, to the point of maintenance and repair, the power loss coefficient in case of dusting of the solar module, the cost of performing maintenance, as well as the frequency of maintenance. Article describes the boundaries of the choice of operating mode of the sprinkler between unscheduled maintenance for cleaning the solar module and the acceptance of additional power of the sprinkler power supply system according to the criterion of minimum operating costs.

scholarly journals Meaningful, but effective? A critical evaluation of Ireland’s citizens’ dialogues on the future of Europe

Politics ◽  
2021 ◽  
pp. 026339572199148
Author(s):  
Anthony Costello
Keyword(s):  
European Union ◽  
Public Relations ◽  
Public Discourse ◽  
Critical Evaluation ◽  
Participatory Approach ◽  
Decision Makers ◽  
Deliberative Process ◽  
Political Will ◽  
The Future

On the 25 March 2017, leaders of the EU27 and European Union (EU) institutions ratified the Rome Declaration. They committed to invite citizens to discuss Europe’s future and to provide recommendations that would facilitate their decision-makers in shaping their national positions on Europe. In response, citizens’ dialogues on the future of Europe were instituted across the Union to facilitate public participation in shaping Europe. This paper explores Ireland’s set of dialogues which took place during 2018. Although event organisers in Ireland applied a relatively atypical and more systematic and participatory approach to their dialogues, evidence suggests that Irelands’ dialogues were reminiscent of a public relations exercise which showcased the country’s commitment to incorporating citizens into the debate on Europe while avoiding a deliberative design which could have strengthened the quality of public discourse and the quality of public recommendations. Due to an absence of elite political will for a deliberative process, as well as structural weaknesses in design, participants’ recommendations lacked any clear and prescriptive direction which could shape Ireland’s national position on the future of Europe in any constructive or meaningful way.

scholarly journals Influence of Parasitic Resistances on the Input Resistance of Buck and Boost Converters in Maximum Power Point Tracking (MPPT) Systems

Electronics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1464
Author(s):  
Marcin Walczak ◽  
Leszek Bychto
Keyword(s):  
Input Resistance ◽  
Load Resistance ◽  
Maximum Power ◽  
Solar Panels ◽  
Maximum Power Point ◽  
Boost Converters ◽  
Pv Systems ◽  
Point Tracking ◽  
Pv Panel ◽  
Power Point

DC/DC converters are widely used in photovoltaic (PV) systems to maximize the power drained from solar panels. As the power generated by a PV panel depends on the temperature and irradiance level, a converter needs to constantly modify its input resistance to remain at the maximum power point (MPP). The input resistance of a converter can be described by a simple equation that includes the converter load resistance and the duty cycle of the switching signal. The equation is sufficient for an ideal converter but can lead to incorrect results for a real converter, which naturally features some parasitic resistances. The goal of this study is to evaluate how the parasitic resistances of a converter influence its input resistance and if they are relevant in terms of MPPT system operation.

Evaluation of the development ability of medical association based on evidential reasoning and prospect theory

2021 ◽  
pp. 1-18
Author(s):  
Tao Zhang ◽  
Shizheng Li ◽  
Jin Wang
Keyword(s):  
Prospect Theory ◽  
Comprehensive Evaluation ◽  
Risk Attitude ◽  
Decision Makers ◽  
Evidential Reasoning ◽  
Evaluation Index System ◽  
Evaluation Index ◽  
Equivalent Transformation ◽  
Qualitative And Quantitative ◽  
Quantitative Indexes

China has proposed medical couplet body to alleviate residents’ difficulties in seeking medical treatment, and the future development ability of medical couplet body has gradually become a research interest. On the basis of prospect theory, this study constructs a comprehensive evaluation index system with qualitative and quantitative indexes, clear hierarchy, and diverse attribute characteristics. The development ability of medical couplet body is also comprehensively and systematically evaluated. In addition, the evidential reasoning method is proposed on the basis of the equivalent transformation of prospect value. Furthermore, the validity and feasibility of the model are proven through experiments, and the influence of decision makers’ risk attitude on the evaluation results is discussed.

scholarly journals Comprehensive Evaluation of PAXgene Fixation on Oral Cancer Tissues Using Routine Histology, Immunohistochemistry, and FTIR Microspectroscopy

Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 889
Author(s):  
Pooja Lahiri ◽  
Suranjana Mukherjee ◽  
Biswajoy Ghosh ◽  
Debnath Das ◽  
Basudev Lahiri ◽  
...  
Keyword(s):  
Comprehensive Evaluation ◽  
Antigen Retrieval ◽  
Tissue Fixation ◽  
Ftir Microspectroscopy ◽  
Protein Secondary Structures ◽  
Associated Proteins ◽  
Cancer Tissues ◽  
Formalin Fixed ◽  
Fixation System

The choice of tissue fixation is critical for preserving the morphology and biochemical information of tissues. Fragile oral tissues with lower tensile strength are challenging to process for histological applications as they are prone to processing damage, such as tissue tear, wrinkling, and tissue fall-off from slides. This leads to loss of morphological information and unnecessary delay in experimentation. In this study, we have characterized the new PAXgene tissue fixation system on oral buccal mucosal tissue of cancerous and normal pathology for routine histological and immunohistochemical applications. We aimed to minimize the processing damage of tissues and improve the quality of histological experiments. We also examined the preservation of biomolecules by PAXgene fixation using FTIR microspectroscopy. Our results demonstrate that the PAXgene-fixed tissues showed significantly less tissue fall-off from slides. Hematoxylin and Eosin staining showed comparable morphology between formalin-fixed and PAXgene-fixed tissues. Good quality and slightly superior immunostaining for cancer-associated proteins p53 and CK5/6 were observed in PAXgene-fixed tissues without antigen retrieval than formalin-fixed tissues. Further, FTIR measurements revealed superior preservation of glycogen, fatty acids, and amide III protein secondary structures in PAXgene-fixed tissues. Overall, we present the first comprehensive evaluation of the PAXgene tissue fixation system in oral tissues. This study concludes that the PAXgene tissue fixation system can be applied to oral tissues to perform diagnostic molecular pathology experiments without compromising the quality of the morphology or biochemistry of biomolecules.

Sign in / Sign up

Export Citation Format

Share Document