- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Photovoltaic Module Reliability || Development of Accelerated Stress Tests
摘要： The chapter discusses the development of accelerated stress tests (ASTs) for photovoltaic (PV) modules to identify and mitigate field failure modes. It outlines various ASTs such as Thermal Cycling, Damp Heat, Humidity Freeze, UV Light Exposure, Static Mechanical Load, Cyclic (Dynamic) Mechanical Load, Reverse Bias Hot Spot Test, Bypass Diode Thermal Test, and Hail Test, detailing their parameters and the failure modes they address. The importance of ASTs in improving module reliability and lifetime is emphasized, along with the challenges in accelerating certain processes without altering the failure mechanisms.
关键词： Reverse Bias Hot Spot Test,UV Light Exposure,Damp Heat,Static Mechanical Load,Hail Test,Thermal Cycling,Photovoltaic Module Reliability,Accelerated Stress Tests,Humidity Freeze,Bypass Diode Thermal Test,Cyclic (Dynamic) Mechanical Load
更新于2025-09-19 17:13:59
-
Study on the Stability of Unpackaged CdS/CdTe Solar Cells with Different Structures
摘要： In this work, the stability of unpackaged CdTe solar cells with di?erent con?gurations was investigated according to the International Electrotechnical Commission IEC 61215-2016. The measurements of thermal cycling from -40°C to +85°C and 24-hour temperature cycling from -40°C to +85°C were carried out in CdS/CdTe solar cells with structures of FTO/CdS/CdTe/Au, FTO/CdS/CdTe/back contact/Au, and FTO/MZO/CdS/CdTe/back contact/Au, respectively. The performances of these cells before and after the thermal aging experiments were investigated by using light and dark I‐V together with C‐V. The results reveal varied performance degradation before and after thermal aging in the cells with di?erent structures. Among these, the most deteriorated device is the one without back contact (BC), whose e?ciency decreased by 25.12% after thermal cycling accompanying an obvious roll-over phenomenon when forward bias was greater than open circuit voltage. On the contrary, the reduction in the e?ciency was about 16.80% in the case cells with BC, and the roll-over phenomenon was not so signi?cant. Furthermore, for the devices with optimized front contact of FTO/MZO, the thermal stability was improved obviously. Interestingly, short-circuit current density associated with the carrier concentration of cells remained relatively small variations compared with the change of Voc and ?ll factor. All the results indicated that an e?cient back contact layer and an optimized front electrode were the indispensable structural elements to attain high stabilization in the CdS/CdTe solar cells.
关键词： front electrode,thermal cycling,back contact,CdS/CdTe solar cells,stability
更新于2025-09-19 17:13:59
-
[IEEE 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Paris, France (2019.9.1-2019.9.6)] 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Realizing Asymmetric Boundary Conditions for Plasmonic THz Wave Generation in HEMTs
摘要： As a key component in the wind turbine system, the power electronic converter and its power semiconductors suffer from complicated power loadings related to environment, and are proven to have high failure rates. Therefore, correct lifetime estimation of wind power converter is crucial for the reliability improvement and also for cost reduction of wind power technology. Unfortunately, the existing lifetime estimation methods for the power electronic converter are not yet suitable in the wind power application, because the comprehensive mission profiles are not well specified and included. Consequently, a relative more advanced approach is proposed in this paper, which is based on the loading and strength analysis of devices and takes into account different time constants of the thermal behaviors in power converter. With the established methods for loading and lifetime estimation for power devices, more detailed information of the lifetime-related performance in wind power converter can be obtained. Some experimental results are also included to validate the thermal behavior of power device under different mission profiles.
关键词： power semiconductor device,lifetime prediction,thermal cycling,wind power,IGBT,mission profiles
更新于2025-09-19 17:13:59
-
Sunny with a chance of curtailment: Operating the U.S. grid with very high levels of solar photovoltaics
摘要： With rapid declines in solar photovoltaic (PV) and energy storage costs, futures with PV penetrations approaching or exceeding 50% of total annual U.S. generation are becoming conceivable. The operational merits of such a national-scale system have not been evaluated sufficiently. Here, we analyze in detail the operational impacts of a future U.S. power system with very high annual levels of PV (>50%) with storage. We show that load and operating reserve requirements can be met for all hours while considering key generator operational constraints. Storage plays an active role in maintaining the balance of supply and demand during sunset hours. Under the highest PV penetration scenario, hours with >90% PV penetration are relatively common, which require rapid transitions between predominately conventional synchronous generation and mostly inverter-based generation. We observe hours with almost 400 GW (over 40%) of economic curtailment and frequent (up to 36%) hours with very low energy prices.
关键词： Photovoltaic generation,energy storage,net load,renewables,energy prices,solar energy,thermal cycling,curtailment,production cost modeling,ramping
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Effect of Peak Temperature and Ramp Rate on Thermal-Cycling Results of PV Modules
摘要： Extended thermal cycling was carried out on commercial crystalline silicon solar cell modules with four different temperature profiles. The standard profile followed IEC 61215-2:2016 MQT 11, cycling between the standard temperature range from -45 and 85°C, with the standard ramp rate of 100°C/hr. A high-peak profile cycled between -45 and 100°C, with the standard ramp rate. A fast-ramp profile cycled the standard temperature range, with a faster ~180°C/hr ramp rate. Finally, a high-peak-and-fast-ramp profile cycled the extended temperature range (-45 to 100°C) with the faster ramp rate (~180°C/hr). STC power measurements were obtained after every 100 cycles. Our results show that the peak temperature has a statistically significant effect on the power loss, and that the effect can be explained with the Coffin-Manson-style relationship proposed in IEC 62892.
关键词： photovoltaic module,thermal cycling
更新于2025-09-19 17:13:59
-
Mechanical Reliability of Photovoltaic Cells under Cyclic Thermal Loading
摘要： Metallic coatings placed on solar cell should retain their structural integrity over the life-span of the devices in order to ensure their reliable functioning. One critical component of such a life-assessment exercise is based on their response to the cyclic thermal stresses generated due to the temperature fluctuation, which is inevitable during regular operation of a solar cell and the difference in the thermal expansion coefficients of metal coatings and Si. Here, we have studied the impact of accelerated thermal cycling on the integrity of the semiconductor–metal layer in a commercial monocrystalline Si based photovoltaic solar cell comprising Ag finger-lining and Al backside coating. We observed that, compared to Si-Ag interface, the Al-Si interface was significantly weaker, wherein cracks easily nucleated and grew during thermal cycling between ?40°C and 90°C. The experimental results were augmented with finite element method (FEM), including extended-FEM (XFEM), simulations using geometry based on the actual microstructure of various metal-Si interfaces in the solar cell module. FEM-based simulations suggest excessive stress concentration at the interface of Al-Si eutectic-Al layers due to the irregular wavy nature of this interface. XFEM results indicate the critical role of the interfacial adhesion strength and roughness of the eutectic-Al interface on the crack growth and its propagation path. Based on the obtained results, a discussion on the fabrication of solar cell modules resistant to thermal stress induced structural damage is presented.
关键词： thermal cycling,metal-Si interface,Fracture,Si based solar cells,XFEM
更新于2025-09-12 10:27:22
-
AIP Conference Proceedings [AIP Publishing 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Fes, Morocco (25–27 March 2019)] 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Development and investigation of linear Fresnel lens for concentrator space solar arrays
摘要： Highly efficient ultra-lightweight doubled linear Fresnel-lens concentrators of solar light, which operate in tandem with multijunction InGaP/GaAs/Ge solar cells, have been developed and fabricated. The concentrators have a total photoactive area of (50 × 100) mm2, with the total thickness of ≤0.35 mm and optical focus of 32 mm. The Fresnel profile of each linear lens in the concentrator is formed from silicone rubber on ≤ 100 μm radiation-hard glass. The efficiency of the linear lens concentrators was 90% for the AM0 spectrum (1367 W/m2). The efficiency of the concentrators was examined before and after the irradiation and thermal-cycling tests. A 10% decrease in the efficiency of the linear lens concentrators is observed upon irradiation with 1 MeV electrons at a fluence of 3×1015 cm-2 and a <10% decrease upon thermal-cycling after the radiation treatment. The optical efficiency of the linear lens concentrators decreased by 13% after crush-testing with the total damage area being 2.5%.
关键词： solar concentrator,space solar arrays,Fresnel lens,radiation hardness,thermal cycling
更新于2025-09-11 14:15:04
-
Equi-biaxial compressive strain in graphene: Grüneisen parameter and buckling ridges
摘要： Here we report equi-biaxial compressive strain in monolayer graphene on SiO2 and Si3N4 substrates induced by thermal cycling in vacuum. The equi-biaxial strain is attributed to the mismatch in coefficient of thermal expansion between graphene and the substrate and sliding of graphene on the substrate. Importantly, the induced buckling ridges in graphene exhibit a pattern representing the symmetry of graphene crystal structure, which agreed well with our molecular dynamics (MD) simulations. Furthermore, these thermally-induced buckling ridges were found reminiscent of those in graphene synthesized by the CVD and SiC sublimation methods, suggesting the same origin of formation of the buckling ridges.
关键词： biaxial strain,thermal cycling,graphene,buckling ridges,molecular dynamics simulation,Grüneisen parameter
更新于2025-09-09 09:28:46