Reliability Of Modules Research Articles

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.

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

An IGBT coupling structure with a smart service life reliability predictor using active learning

Abstract An effective approach is proposed to evaluate the service life reliability of a multi-physics coupling structure of an insulated gate bipolar transistor (IGBT) module. The node-based smoothed finite element method with stabilization terms is firstly employed to construct an electrical-thermal-mechanical (ETM) coupling structure of the IGBT module, based on which the multi-physics responses can be accurately calculated to predict the service life of the IGBT module. By using the high-quality sample data obtained through the ETM coupling model, a Monte Carlo based active learning Kriging metamodel (AK-MCS) is developed to assess the service life reliability of the IGBT module, which can greatly reduce the computational cost needed by the surrogate model construction and reliability analysis. Numerical results show that the proposed ETM coupling structure can produce high-quality sample data of the IGBT dynamics and the AK-MCS machine learning technique can accurately estimate the service life reliability of the IGBT module.

Sequential thermomechanical stress and cracking analysis of photovoltaic modules with full and half-cut cells

The transition from conventional full-cell patterns to half-cell modules in the photovoltaic (PV) industry promises enhanced stability and efficiency. This study investigates the thermomechanical behaviour and stress distribution within half-cell and full-cell PV modules during the manufacturing and operational phases. Using finite element modeling, the research simulates sequentially the manufacturing and operating processes such as laser cutting, soldering, lamination, mechanical loading and thermal cycling. The Extended Finite Element Method (XFEM) predicts crack initiation and propagation in the crack-sensitive regions in PV modules during their entire life. Key findings highlight stress concentrations during manufacturing, influenced by parameters like laser power, scribing length and Silicon wafer size. Mechanical loading (ML) and thermal cycling (TC) induce additional stresses, impacting module reliability. The results are useful for the optimization of material properties and the development of advanced design strategies contributing to the durability and efficiency of PV systems.

Game psychotherapy intervention based on entertainment interactive robots for preventing depression in university students

This study designs an entertainment interactive robot system for gaming psychotherapy intervention and evaluates its effectiveness in preventing depression in students. In terms of the architecture and hardware of the entertainment interactive robot system, the robot adopts high-performance processors and sensors to achieve the ability to quickly respond and accurately perceive user actions. In terms of software, a mathematical model was established based on the structure and kinematic principles of the robot to describe its motion. Preprocess user gesture data by analyzing the features and patterns of user gestures, extracting key action information, and using machine learning algorithms or deep learning models to classify and recognize gestures to determine user intent and action types. Evaluate action recognition and effectiveness, and verify the accuracy and reliability of the gesture interaction module through comparison and testing with actual user gestures. The study designed an entertainment interactive robot assisted game that provides a fun and interactive experience to attract students’ attention and stimulate positive emotions. Through game design and behavioral pattern evaluation, the research team evaluated the preventive effect of entertainment interactive robot assisted games on depression and proposed optimization strategies.

Validity and Reliability of the Spiritual Counselling Intervention Module (MIKS)

Validity and Reliability of the Spiritual Counselling Intervention Module (MIKS)

Avionics Module Fault Diagnosis Algorithm Based on Hybrid Attention Adaptive Multi-Scale Temporal Convolution Network.

Since the reliability of the avionics module is crucial for aircraft safety, the fault diagnosis and health management of this module are particularly significant. While deep learning-based prognostics and health management (PHM) methods exhibit highly accurate fault diagnosis, they have disadvantages such as inefficient data feature extraction and insufficient generalization capability, as well as a lack of avionics module fault data. Consequently, this study first employs fault injection to simulate various fault types of the avionics module and performs data enhancement to construct the P2020 communications processor fault dataset. Subsequently, a multichannel fault diagnosis method, the Hybrid Attention Adaptive Multi-scale Temporal Convolution Network (HAAMTCN) for the integrated functional circuit module of the avionics module, is proposed, which adaptively constructs the optimal size of the convolutional kernel to efficiently extract features of avionics module fault signals with large information entropy. Further, the combined use of the Interaction Channel Attention (ICA) module and the Hierarchical Block Temporal Attention (HBTA) module results in the HAAMTCN to pay more attention to the critical information in the channel dimension and time step dimension. The experimental results show that the HAAMTCN achieves an accuracy of 99.64% in the avionics module fault classification task which proves our method achieves better performance in comparison with existing methods.

Performance Degradation and Protective Effects of Atomic Layer Deposition for Mg‐based Thermoelectric Modules

AbstractThermoelectric technology has witnessed a resurgence in recent years due to increasing demands for sustainable energy sources and efficient cooling systems. Recently, the introduction of Te‐free thermoelectric modules using non‐toxic, abundant materials including p‐type MgAgSb and n‐type Mg3(Sb,Bi)2 marked a significant breakthrough. Despite promising performance, questions persist regarding long‐term robustness and stability, especially in harsh environments. In this study, a thorough exploration of thermoelectric modules is conducted, focusing on their performance degradation under various conditions. Through elemental mapping analysis, degradation mechanisms are identified within the modules during cycling in argon environments, where atomic migrations and the formation of complex oxides at contact regions are key factors. Furthermore, cycling tests in air reveal significant degradation, prompting the exploration of protective strategies. Surface coatings using atomic layer deposition (ALD) emerge as a promising solution, particularly by HfO2, demonstrating superior protective effects. Furthermore, re‐soldering effectively restores module performance is found, highlighting the importance of developing advanced soldering techniques to promote magnesium‐based thermoelectric technology as a sustainable alternative to Bi2Te3. These findings emphasize the importance of exploring novel contact materials and demonstrate the potential of ALD as a universal approach to enhancing module reliability and robustness.

Comprehensive review on performance, reliability, and roadmap of c‐Si PV modules in desert climates: A proposal for improved testing standard

AbstractDesert regions have emerged as ideal places for GW utility‐scale photovoltaic (PV) module installations because of their ultra‐large spaces, abundance of high‐irradiance sunshine hours, and clear sky. However, the harsh desert climate presents challenges to the reliability and bankability of PV modules. This review provides an in‐depth understanding of the unique desert parameters impact, desert‐induced degradation modes, status, and required properties of the bill of materials (BOMs) and suggestions for the development of desert standards. The review reveals that the climatic conditions in the desert are considerably harsher than those in the moderate climate. The main degradation mechanisms caused by the desert are ultraviolet (UV)‐induced discoloration, thermomechanical flaws of interconnects, and glass abrasion (because of soiling). The development of desert modules may necessitate the use of new‐generation modules with low‐temperature coefficients, high efficiency, high bifaciality, stability under UV light, and elevated temperatures. For the desert module application, options include advanced back sheets and encapsulants that are thermally and UV stable, free of acetic acid groups, and have a low water vapor transfer rate. The degradation modes induced by desert climate are not sufficiently addressed by the present environmental and safety standards through accelerated aging tests. As a result, this article provides a summary of current standards and recommends creating a new testing proposal called the “Hot Desert Test Cycle (HDTC)” sequence that is specific to the desert climate. This comprehensive review catalyzes the PV community to explore novel designs and develop desert PV modules while adhering to localized standards.

Encapsulation strategies for mechanical impact and damp heat reliability improvement of lightweight photovoltaic modules towards vehicle-integrated applications

Lightweight modules are essential for next-generation vehicle-integrated photovoltaic (VIPV) applications, such as solar-powered cars, allowing integration of solar cells beyond the roof, and on the hood, boot and body panels, and thereby extending the driving range. However, the lightweight module's reliability and corresponding degradation mechanisms under various environmental stresses are less researched. In this work, we investigate interconnection and encapsulation strategies to improve reliability against damp heat and mechanical impact. We fabricated lightweight mini modules, weighing around 3.45 kg/m2, and conducted hail impact and damp heat tests. These tests result in different failures, such as cracks in the solar cell, module delamination, and microcracks in the backsheet. By carrying out failure mechanism analysis and altering the fiber reinforcement in backsheet and encapsulation materials, we can increase resilience to these failure modes, thus providing guidance for the design of lightweight PV modules for next-generation VIPV.

Frequency Regulation Adaptive Control Strategy of Wind Energy Storage System for Wind Speed Uncertainty

In order to reduce the negative influence of wind speed randomness and prediction error on frequency modulation, the reliability of the wind storage system was assessed effectively. In the wind storage frequency modulation system, a state of charge (SOC) adaptive adjustment method for wind speed randomness is proposed. Firstly, through the correlation analysis between the standby capacity of frequency modulation and the output power of wind turbine, the uncertainty of its frequency modulation capacity is revealed. Secondly, in view of the uncertainty of wind turbine frequency modulation, the output power of energy storage frequency modulation is optimized with the goal of minimizing the frequency modulation power deviation of the wind storage front under the framework of model predictive control, and the improved whale optimization algorithm (WOA) is used to solve the problem. Finally, the simulation results show that, under the given 5 min continuous disturbance, the root mean square of frequency regulation of the proposed restoration method is reduced by 56.65% compared to the SOC recovery base point set to 0.5. Under continuous large perturbations, the maximum frequency deviation is reduced by 0.0455 Hz. This effectively shows that this method can not only improve the frequency modulation reliability of wind power system but also improve the continuous frequency modulation capability of energy storage system.

Soldering Pressure Effect on Lifetime of Thermoelectric Modules under Thermal Cycling.

For practical industrial applications, enhancing the longevity and the reliability of thermoelectric modules (TEMs) is equally as crucial as improving their conversion efficiency. This study proposes a strategy for extending the lifespan and introduces the quality evaluation criteria for the most extensively used commercial bismuth telluride TEM. By varying the soldering pressure during module assembly, its impact on the quality of the module's internal interfacial connections was investigated, via analyzing its contact resistivity, shear modulus, and antifatigue ability through thermal cycling tests. The findings reveal that increasing the soldering pressure leads to a slight reduction in interfacial contact resistivity and has no significant effect on the shear modulus but notably enhances the module's antifatigue ability during thermal cycling tests. According to the SEM results, it can be evidently deduced that the aforementioned phenomena are directly correlated with the size and quantity of voids distributed in the solder layer, which is regarded as the origin of antifatigue ability. Thus, it can be inferred that augmenting the soldering pressure represents an effective approach to prolonging the lifespan of TEMs assembled by using the soldering method. Furthermore, the existence of voids within the solder layer can serve as a criterion for an initial assessment of module longevity. This study provides a reference for both the industrial assembly and lifespan evaluation of commercial bismuth telluride TEMs.

Optimal design of water immersion sensor layout for helicopter emergency flotation system based on the nsgaII algorithm

Aiming at the problem of sensor layout in an emergency flotation system, a sensor layout scheme design method based on the NSGAII method is proposed. The ALE method is used to simulate the water landing process of the helicopter on different pitch angles. The logic relationship of the 4/5 voting system is used to improve the sensor module reliability. Further, a mathematical model of layout scheme is established to maximize the detection coverage and minimize the force acting on the water immersion sensors when helicopter emergent water landing as the objective functions. Based on the mathematical model of water immersion sensor layout optimization constructed in this paper, NSGAII is used to solve this problem. The results show that the proposed method can realize the optimization of the layout of the water immersion sensor, the detection coverage of optimized schemes is increased by 3.26% on average compared with the value under the original scheme, and the force acting on the water immersion sensors is reduced by 61.86%.

Analysis and prediction of the performance and reliability of PV modules installed in harsh climates: Case study Iraq

The increasing global demand for renewable energy necessitates a comprehensive understanding of solar photovoltaic (PV) system performance and reliability, particularly in harsh climates such as Iraq. Despite ambitious targets to diversify its energy sector, Iraq faces challenges in the deployment of PV projects due to limited field experience. In this study, we assess the reliability and performance of two different PV systems installed in Basrah and Baghdad, aged 3.5 and 8 years, respectively. Field analysis reveals prevalent issues including glass and cell breakage, delamination, solder bond fatigue, and encapsulant discoloration, contributing to medium degradation rates of 0.91 %/year and 2.6 %/year in Basrah and Baghdad, respectively. Our investigation attributes higher degradation rates not only to ageing but also to suboptimal operation and maintenance (O&M) practices. Additionally, since the two systems are from different manufacturers, we verify that the measured higher degradation rates are mainly attributed to harsh operating conditions rather than differences in manufacturing processes. To extrapolate our findings countrywide, we employ a physics-based model to simulate the degradation rates. Based on the simulated degradation, we proposed four degradation rate zones across the country with degradation rates ranging from 0.62 %/year to 0.96 %/year. By applying these rates to estimate lifetime energy yield across different zones, we demonstrate the trade-offs between higher irradiance zones with reduced PV lifetime and low irradiance zones with longer PV lifetimes. In the study, we compared energy yield simulations using fixed degradation rates with those employing climate-dependent degradation rates. Our analysis revealed that in certain locations in Iraq, employing a fixed degradation rate underestimates the yield by approximately 9.7 %. Conversely, in other locations, it results in overestimations ranging from approximately 10.5 %–31.1 %, highlighting the importance of accurate degradation rate modelling for PV system assessment. Furthermore, we simulate the impact of soiling losses on energy yield, revealing potential losses of up to 70 % depending on location and cleaning schedules. Our findings contribute valuable insights into PV system degradation across harsh climates, addressing critical gaps in global degradation rate data and facilitating more accurate climate-dependent assessments of PV performance and reliability.