Reliability Of Modules Research Articles

Sustainable Solar Module Through the Substitution of Materials by Renewable Encapsulation, Recycled Backsheet, and Lead‐Free Interconnection

ABSTRACTSustainability and resource‐efficiency are the major topics for the 21st century. Most of the PV modules are manufactured of glass, polymers, metals, and silicon‐based solar cells. All these materials have the potential to be substituted by sustainable products. The substitution of materials for PV modules is challenging because of issues in significant unknown risks for short‐ and long‐term reliability of the PV module. Investigations for material and process routes of a 100% renewable solar module are necessary. This study investigates the suitability and reliability of different materials. For example, the reliability of an electrically conductive adhesive (ECA) to a leaded‐solder reference is under investigation as well as various polymers (recycled, bio‐based, or biodegradable). In the first step, the interconnections are tested with a standard module encapsulation bill of materials (known good reference). In the second step, the module encapsulation and backsheet materials are substituted by their sustainable counterparts. The goal is to identify the most promising material combinations for further integration of lead‐free interconnected solar cells. Reliability is assessed using accelerated ageing tests in accordance with IEC 61215/IEC 61730 with standard test duration and extended test duration for each material and interconnection batches. The condition of the samples is assessed by regular visual inspection, power measurements, and electroluminescence images. The study aims to demonstrate and assess the suitability and reliability of the selected material combinations to enable the steps toward a renewable material solar module.

Reliability assessment of the thyristor module of high-voltage hybrid switchgears in reservation conditions

In the article, the authors proposed a methodology for evaluating the main indicators of the operational reliability of a high-voltage thyristor module, which is an element of electric power equipment, using the example of the design of such electrical devices as hybrid switches and converters in the structure of traction substations, power supply systems of metallurgical complexes, etc. The proposed method makes it possible to estimate the prob-ability of failure-free operation of the real design of the thyristor module, taking into account its design and implementation scheme, as well as the level and depth of redundancy of the semiconductor devices included in it. As initial data, the proposed method involves the use of electrical load parameters in terms of voltage and current and their redistribution as the reserve resource is exhausted, taking into account the design features of both the electrical device itself and the power supply network where it is located. is established. The proposed method makes it possible to evaluate the effectiveness of the influence of design factors (the number of semiconductor devices, the principle and depth of redundancy, the economic component, etc.) on the main indicators of the operational reliability of the corresponding types of high-voltage equipment, taking into account the electrical load and its changes. The proposed method was tested on the example of a real scheme of the thyristor module of the on-load tap-changer switching device, which was in industrial operation for a long time in the most unfavourable conditions in the power supply structure of the metallurgical industry, where there is high switching frequency, load fluctuations, etc. The implementation of this technique in the conditions of designing high-voltage switching and converting electrical equipment, as well as its operation in the power supply structure, allows to evaluate the influence of the structural features of the semiconductor part, taking into account the load mode, as well as the influence of external and operational factors. A more accurate determination of the effectiveness of the proposed methodology for predicting operational reliability indicators depending on the mode and depth of the load and the type of backup system can be achieved by conducting an additional series of experimental tests on the choice of the type of theoretical system. distribution law and determination of its parameters for specific designs of electrical devices. Thus, a conclusion was made about the possibility of using the obtained results to evaluate the parameters of the operational reliability of the above-mentioned high-voltage equipment, which is used as part of switchgear and power supply systems in both high and low voltage conditions.

Quantifying Measurement Uncertainty in Photovoltaic Module Performance at Standard Test Conditions: A Machine-Based Approach

This paper presents an in-depth analysis of measurement uncertainty in the output parameters of photovoltaic (PV) devices, focusing specifically on measurements conducted under standard test conditions (STC). Accurate characterization of module I-V performance is crucial for PV manufacturers, researchers, and investors alike. The study provides a comprehensive overview of the measurement procedures for both performance and temperature coefficient of PV modules, with a strong emphasis on the detailed calculation of associated uncertainties. Notably, the research was conducted under real-world sunlight conditions, with special attention given to reference devices such as reference cells, modules, or pyranometers, which play a pivotal role in determining overall uncertainty components. By utilizing a diverse array of machines from various sources, the results obtained are applicable across a wide range of measurement configurations. Furthermore, adherence to the ISO/IEC 17025 series of standards ensures a standardized and reliable approach. The novelty of this research lies in its comprehensive approach to uncertainty analysis, encompassing both performance and temperature coefficient measurements under real-world conditions. By providing valuable guidelines for PV module characterization and reliability assessment, particularly in uncertainty estimation, this study contributes significantly to the advancement of photovoltaic technology.

How to Combine SHJ Cell-Edge Passivation and Module Reliability?

The use of cut-cells in most of the current modules is now the norm to maximise the final product performances. But the integration of such new cell configurations also comes with new challenges, especially if small cell size dimensions such as shingle are considered. Indeed, specific edge passivation processes are often used to recover for the cut-cell losses. Alumina Oxide or Polymer deposition are the most studied approaches, with in general promising benefits proven at cell level. However, only few communications after module integration are available, in particular about the impact of these additional layers on final module reliability. We show for example that it is crucial to avoid direct deposition of AlOX over the cell metal pattern in the future interconnection area, as TC (Thermal Cycling) resilience of such modules is clearly degraded. Proper edge localization of the AlOX layer is needed to recover the initial reliability behaviour. To preserve the interconnection quality, three different approaches are investigated: (1) edge localisation of the layer by wafer stacking during deposition (2) introduction of adapted copper plating solutions allowing metal growth through the passivation layer (3) edge passivation process directly applied on final strings just before lamination.

Indium Reduction Above 70% in SHJ Solar Cells: Study of the Module Stability

This work focuses on reducing In-based TCO thicknesses to their minimum in SHJ solar cells with the goal to demonstrate the possibility of a drastic reduction of indium consumption in the fabrication process. On the front side, the reduction of the ITO thickness down to 15 nm implies to deposit an additional anti-reflective layer. Three anti-reflective dielectric layers have been studied (SiNx, SiOx and a bilayer SiNx/SiOx) in solar cell and module configurations to maximize the performances and evaluate the module stability under UV exposure. Lower Jsc losses after 120 kWh of UV exposure are measured with the use of thinner ITO layers, in agreement with a lower EQE deterioration in the IR range. The use of SiNx dielectric results in the highest stability under UV and to the best performances after 120 kWh. Following further optimizations of the dielectrics and TCO, the 15 nm of ITO/SiNx option was combined with a thin IMO:H TCO on the rear side. TCO thicknesses down to 30 nm were studied on the rear side resulting in overall indium reduction of 77.2% with very limited efficiency loss at the cell level (below 0.1% absolute after light-soaking). Module reliability of these very low indium content solar cells was studied under UV and damp heat treatments highlighting lower degradations than reference cells for UV and promising results after damp heat test.

Thermo-mechanical stress modelling and fracture analysis on ultra-thin silicon solar cell based on super multi-busbar PV modules

Thinning of crystalline silicon (c-Si) wafers will reduce material cost and improve productivity, which significantly impacts the development of solar photovoltaic (PV) industry. However, this process leads to reduction in mechanical strength of the cell and increased solar cell fracture during the manufacturing process. This study investigates the mechanical property of full wafers and half wafers with varying thicknesses, both before and after the slicing process. Thermo-mechanical stress in half cells was analyzed using finite element modeling (FEM) to clarify the origin of cracks, the influence of Si thickness on cracking and the process impacts on eventual cell breakage. Fracture analysis was implemented not only in soldering process but also during lamination and dynamic mechanical loading (DML) tests. Our findings reveal that the thinner solar cells become even more fragile and susceptible to fracture or power attenuation during the module manufacturing process and operation as well. FEM simulations also verify that the highest stress occur in the thinnest Si wafers after soldering, lamination and DML processes, respectively. However, the choice of 16 Cu ribbons with a diameter of 0.26 mm, which is verified and confirmed as the optimal super multi-busbar (SMBB) technology for the ultra-thin solar cells based PV module, can help to reduce the cell stress and improve the module reliability in mass production.

Validity and reliability of the career guidance module for excellent performance (PACU) among civil servants

The development of the PACU includes three submodules focused on Motivation, Job Satisfaction, and Resilience. It is grounded in psychological theories such as Self-Determination Theory (SDT), the Theory of Work Adjustment (TWA), the London Career Motivation Theory (LCMT), and Reality Therapy. The development process followed Sidek's Model, a Malaysian-based framework for module development. This study aims to assess the validity and reliability of a counseling module designed for employee career development, called the "Performance Career Guidance Module." To evaluate the module's validity, assessments were obtained from eight experts in counseling, psychology, and counseling practice. Additionally, a pilot test was conducted with 30 government employees to assess the module's reliability. The results indicated a high level of validity, with a score of 0.80. The findings also showed an impressive overall reliability coefficient, with a Cronbach's Alpha value of 0.92. These results highlight the module's effectiveness in enhancing motivation, job satisfaction, and resilience among employees. The high reliability and validity of the module suggest its potential to address workplace challenges effectively. This study contributes to the broader field of counseling, offering valuable insights for counselors addressing various employee issues.

Kolmogorov-Arnold Network in the Fault Diagnosis of Oil-Immersed Power Transformers.

Instabilities in energy supply caused by equipment failures, particularly in power transformers, can significantly impact efficiency and lead to shutdowns, which can affect the population. To address this, researchers have developed fault diagnosis strategies for oil-immersed power transformers using dissolved gas analysis (DGA) to enhance reliability and environmental responsibility. However, the fault diagnosis of oil-immersed power transformers has not been exhaustively investigated. There are gaps related to real scenarios with imbalanced datasets, such as the reliability and robustness of fault diagnosis modules. Strategies with more robust models increase the overall performance of the entire system. To address this issue, we propose a novel approach based on Kolmogorov-Arnold Network (KAN) for the fault diagnosis of power transformers. Our work is the first to employ a dedicated KAN in an imbalanced data real-world scenario, named KANDiag, while also applying the synthetic minority based on probabilistic distribution (SyMProD) technique for balancing the data in the fault diagnosis. Our findings reveal that this pioneering employment of KANDiag achieved the minimal value of Hamming loss-0.0323-which minimized the classification error, guaranteeing enhanced reliability for the whole system. This ground-breaking implementation of KANDiag achieved the highest value of weighted average F1-Score-96.8455%-ensuring the solidity of the approach in the real imbalanced data scenario. In addition, KANDiag gave the highest value for accuracy-96.7728%-demonstrating the robustness of the entire system. Some key outcomes revealed gains of 68.61 percentage points for KANDiag in the fault diagnosis. These advancements emphasize the efficiency and robustness of the proposed system.

Research Progress of Zero-Busbar Technology Based on Heterojunction Photovoltaic Modules

In order to reduce manufacturing costs, the design of silicon-based solar modules is changing from a super-multi-busbar design to a zero-busbar (0BB) design. In this study, two different 0BB technologies based on heterojunction with intrinsic thin-layer solar cells—conventional soldering, and Integrated Film Covering (IFC)—were investigated. IFC-based 0BB technology was found to have a lower contact resistance, which well matches the theoretical calculations and module power testing results. To further measure module reliability, a series of tests on solders and silver pastes were carried out. The results show that Sn43Pb43Bi14 solder is more suitable for soldering-based 0BB technology, whereas Sn32Pb42Bi26 solder is more suitable for IFC-based technology. Additionally, silver paste, which is used for solder ribbon contact areas (SRCAs), is suitable for soldering-based 0BB technology. When Ag@Cu paste is used in SRCAs with IFC-based 0BB technology, a reliable connection can also be achieved. After optimization, modules using both techniques were subjected to and passed lifetime tests, including the thermal cycling, humidity freeze, and hot-spot tests required in IEC standards, as well as more rigorous tests such as thermal–dynamic and thermal–static mechanical loading. The results show that the two technologies have great potential for future mass production.

Reliability of Commercial TOPCon PV Modules—An Extensive Comparative Study

Reliability of Commercial TOPCon PV Modules—An Extensive Comparative Study

Progress in Improving Photovoltaics Longevity

With the increase of photovoltaic (PV) penetration in the power grid, the reliability and longevity of PV modules are important for improving their payback period and reducing recycling needs. Although the performance of PV systems has been optimized to achieve a multi-fold increase in their electricity generation compared to ten years ago, improvements in lifespan have received less attention. Appropriate operation and maintenance measures are required to mitigate their aging. PV cells and modules are subject to various degradation mechanisms, which impact their long-term performance and reliability. Understanding these degradation processes is crucial for improving the lifetime and sustainability of solar energy systems. In this context, this review summarizes the current knowledge on key degradation mechanisms (intrinsic, extrinsic, and specific) affecting PV modules, as well as on-site and remote sensing methods for detecting PV module defects and the mitigation strategies employed for enhancing their operational lifetime under different climatic conditions in the global environment.

The Potential of ‘Self-Ie’ Module as SDG’s Work Performance Intervention for Malaysian Low-Performing Civil Servants

Background: The SELF-IE module was developed by integrating the Reality Therapy Theory and the Transtheoretical Model (TTM) of Bahaviour Change, in order to obtain a module that is suitable for the intended target group. The module was applied in programs involving mental health, physical health, counseling, and financial management that acted as a holistic counseling psychology intervention. Objective: The objectives of this study were to obtain the validity and reliability of the SELF-IE module which involved five (5) experts who are psychology officers, university lecturers, and civil servants. Methods: The validity was measured in terms of content validity, whereas the reliability was determined via the Cronbach's Alpha (α) value calculated by the Statistical Package of Social Sciences (SPSS) Results: After the analysis, it was found that the minimum percentage obtained for content validity was 80.4%. Meanwhile, the reliability showed that the degree of agreement among experts was high, with the value of α = 0.864. Conclusion: The results indicated that SELF-IE module has high validity and reliability; thus, it could be used effectively as counseling psychology intervention to assist the low-performing civil servants. The module possessed the potential to also be applied for the same group of employees in private sector as SDG’s tool for work performance improvement.

Techno-economic viability of sustainable solar co-generation using CPV cells in parabolic dish concentrators: A 20-year perspective

Solar co-generation is a cutting-edge technology that enables the instantaneous production of electricity and heat energy by employing concentrated solar power (CSP) systems. This study presents the development and experimental analysis of a novel small-scale solar co-generation system, utilizing concentrated photovoltaic (CPV) cells integrated into a solar paraboloidal dish concentrator (SPDC) for simultaneous electricity and heat production. The system, designed with a high concentration ratio, employs a CPV module composed of four 1 cm × 1 cm cells mounted on a flat receiver of a parabolic dish concentrator with an aperture area of 12.6 m2. Experimental results, obtained over three consecutive days, demonstrate that the CPV module achieves an electric power output ranging from 480 to 645 W daily, while the SPDC system generates thermal energy between 395 and 725 W. The economic analysis indicates a cost of ₹10.75 per unit of electricity, with a payback period of approximately 13.5 years, assuming a 20-year system lifespan. Additionally, the reliability of the CPV module and the impact of varying encapsulation materials were critically assessed, providing insights into potential improvements and long-term performance. The findings underscore the viability and economic potential of solar co-generation systems employing CPV technology, contributing to the advancement of sustainable energy solutions.

Preparation of Imidazole Compounds as Latent Curing Agents and Their Application in RGB LED Packaging.

LED packaging miniaturization has raised more requirements for LED materials. As a material contacting the LED chip directly, the reliability of LED non-conductive adhesive has also garnered increasing attention. This study optimized the formula for non-conductive adhesives for an imidazole curing system. The optimized composition of the adhesive is 25%wt for the curing agent and 30%wt for the silica. The prepared non-conductive adhesive has a 7-day pot life and 9-month storage stability. The shear strength reached 87 g and 72 g at 25 °C and 160 °C, respectively. The reliability of the LED modules packaged with the non-conductive adhesive was researched. The green and blue light intensity change was 4.7%, 43.7%, respectively, indicating good anti-aging properties. The blue light decay was mainly due to adhesive aging. The non-conductive adhesive effectively prevented "caterpillar" growth. This provides useful and practical guidelines for industry for applications of adhesive in different packages.

Evaluating the Impact of Edge-Seal on the Performance of Double-Glass Solar Photovoltaic Modules

Solar energy is a vital component of the renewable energy landscape. Nevertheless, photovoltaic (PV) modules face numerous challenges during operation due to environmental stress factors, which can lead to various degradation issues such as delamination, encapsulant discoloration, corrosion of cell metallization, and potential-induced degradation. Ethylene-vinyl acetate (EVA), despite being a prominent encapsulant material, is notably vulnerable to moisture. Upon degradation, EVA releases acetic acid, severely impacting the long-term performance of PV modules. This study investigates the effectiveness of using a polyisobutylene-based edge-seal to minimize moisture ingress in double-glass modules. One-cell mini-modules encapsulated with EVA, with and without edge-seal, are subjected to damp heat testing (85°C / 85% RH) for up to 5000 hours and their performance are evaluated though current-voltage characteristics. Mini-modules without edge-seal exhibit a significant 70% loss in power, primarily due to a 37% decrease in short-circuit current, a 56% decrease in fill factor, and a staggering 650% increase in series resistance. However, mini-modules with edge-seal see only a 33% loss in power, driven mainly by a 21% decrease in fill factor and a 76% increase in series resistance. The use of edge-seal does not completely prevent but effectively reduces moisture ingress and mitigates its detrimental effects on module performance. Additionally, the Network Structural Equation Modeling approach is applied to analyze current-voltage characteristics, enabling the identification of statistically significant relationships, the construction of degradation pathway diagrams, and the determination of key factors contributing to power degradation. This analysis reveals increased series resistance and reduced fill factor as primary causes of power degradation for both mini-module configurations. Although the encapsulant materials exhibit minimal degradation in optical, chemical, and thermo-chemical properties, the presence of moisture within the module construction can still cause corrosion of cell metallization. This results in a decline in power performance even without substantial acetic acid formation. This study highlights the critical importance of preventing moisture ingress to enhance the durability and reliability of PV modules, ensuring their optimal performance throughout their intended service lifetime.

Validity and Reliability of the Oil Palm Fertilizer Infographic Mobile App Module to Enhance Knowledge Practices in Palm Fertilization among Smallholders

Implementing best practices in oil palm fertilisation is pivotal for enhancing fresh fruit bunch production within the oil palm cultivation sector. However, small-scale farmers in Malaysia still encounter a notable deficiency in understanding fertiliser management. Therefore, providing easily accessible and comprehensible sources of palm fertilisation information is crucial, with a focus on materials containing verified and dependable content from the Malaysian Palm Oil Board (MPOB). This study aims to evaluate the validity and reliability of the oil palm fertiliser infographic mobile app module for smallholders. The module’s content was made simpler by referring to multiple documentation sources regarding recommended palm fertilisers by the Agronomic Unit of the MPOB. The infographic module is designed to encourage best practices in palm fertilisation for smallholders through a user-friendly mobile app platform. A module draft was submitted to five specialists in palm fertiliser and module development to assess its validity. Several improvements were made based on the comments and feedback gained from these experts. 55 individuals, including smallholders, contributed to evaluating the module’s reliability and the impact of the knowledge practices in palm fertilisation. The entire module’s content attained a validity rate of 90%, confirming the acceptance of its content validity. Furthermore, the module recorded a Cronbach’s alpha value of 0.981, indicating a high level of reliability. The utilisation of this module within the mobile app platform suggests that the application could effectively improve users’ knowledge of palm oil fertilisation practices. These findings demonstrated that the Infographic Oil Palm Fertilizer is appropriate and successful in achieving the intended learning objectives.

Verifying and Assessing the Reliability of the Learning Module of Positive Design and Innovative Technology in the Integration Approach of Spiritual Knowledge

This study was carried out to determine the validity and reliability of the learning module known as The Learning Module of Positive Design and Innovative Technology in The Integration Approach of Spiritual Knowledge (PRBTIFIIS). The PRBTIFIIS module has been built to develop the positive innovative thinking of Form 2 students through a knowledge integration approach with the application of the value of trust and obedience to God, human responsibility as a servant and caliph. The PRBTIFIIS module is built based on the Sidek Module construction model that uses the basic theory of Reverse Maslow's Theory, and Sidek's Learning Theory. A level of validation of the module content was carried out by five experts in the studied field. The content validity of the PRBTIFIIS Module is calculated using the Tuckmen and Waheed Level of Mastery Validity formula. The data obtained is 98.7%. The reliability of the module was obtained from 16 second-grade students who participated in the implementation of the pilot study. The Cronbach's Alpha score obtained for the reliability of the module was 0.97. The findings of the study show that the developed PRBTIFIIS Module has high validity and reliability and the PRBTIFIIS module is available to test its effectiveness.

Thermal and hydraulic performance of 3D printed jet impingement configuration for SiC power modules in aerospace propulsion inverters

Efficiently controlling the temperature of power electronic inverters is crucial for aerospace applications with high power density. Effective thermal management strategies could enhance the power output of power inverters to their maximum rated capacity. Jet impingement is a promising technology with outstanding heat transfer characteristics, making it a sophisticated aid for cooling innovation in power inverters. A numerical comparative study was conducted between jet impingement and traditional pin finned heat sink. In our case study, the pin fin could not effectively regulate the junction temperature to a level below 150 °C. By using a 3D printed jet impingement housing composed of polymer, the weight of the power module thermal management system could be decreased by 71 % compared to a metallic pin finned heat sink. Moreover, this approach aids in lowering the junction temperature to 129 °C, under the same boundary conditions. Additionally, a numerical study was conducted on power modules with thermal imbalance used in aerospace inverters. The study proposed various configurations of jet impingement to reduce temperature differences between power module switches, as well as minimize the pressure drop across the jet impingement housing. The primary objective is to minimize the temperature disparity between the unbalanced switches in order to improve the overall reliability and lifespan of the power module, while decreasing the pressure drop. Among all the options, the optimum design achieves a minimal temperature difference of 24 °C between the power module switches, while the pressure drop reaches 12 kPa.

Unveiling the origin of metal contact failures in TOPCon solar cells through accelerated damp-heat testing

Tunnel oxide passivated contact (TOPCon) solar cells are expected to dominate the global photovoltaic market in the coming decade thanks to rapid advancements in power conversion efficiency (PCE). However, there are concerns about the reliability of TOPCon modules, particularly in hot and humid conditions. The current module-level fundamental analysis strategies for TOPCon solar cells provide too slow feedback for rapid process development. This study explores the degradation of metal contacts in TOPCon solar cells under accelerated testing conditions of 85 °C and 85 % relative humidity (DH85). The degradation was induced by two commonly used sodium-related salts, sodium bicarbonate (NaHCO3) and sodium chloride (NaCl), in the testing of the solar cells. When applied to the front side, NaHCO3 caused a ∼5%relPCE reduction after 100-h DH85 exposure, while NaCl leads to a more significant ∼92%relPCE reduction. The primary cause of degradation is a considerable increase in series resistance (Rs), likely due to electrochemical reactions within the Ag/Al paste. When the salts are applied to the rear of the TOPCon solar cell, the degradation becomes more complex. NaHCO3 increases recombination and results in a deterioration of the contact, resulting in a ∼16%relPCE reduction after 100-h DH85 testing. Conversely, NaCl primarily causes a decline in open-circuit voltage (Voc) and a ∼4%relPCE loss. This manuscript primarily investigates degradation mechanisms related on the rear side, with a focus on significant oxidation occurring at the interface between Ag and Si. These findings highlight the susceptibility of TOPCon solar cells to contact corrosion, emphasizing the electrochemical reactivity of metallisation as a potential risk for long-term TOPCon module operation. This study provides crucial insights into TOPCon cell degradation mechanisms, which are essential for optimising performance and enhancing the long-term reliability of TOPCon modules.

Validity and Reliability of the Choice Theory Reality Therapy Group Guidance Module for School Truancy

Validity and Reliability of the Choice Theory Reality Therapy Group Guidance Module for School Truancy