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Results for “Module Reliability”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 397 records · Page 22

Reliability analysis of laminated CMC components through shell subelement techniques

An updated version of the integrated design program C/CARES (composite ceramic analysis and reliability evaluation of structures) was developed for the reliability evaluation of CMC laminated shell components. The algorithm is now split in two modules: a finite-element data interface program and a reliability evaluation algorithm. More flexibility is achieved, allowing for easy implementation with various finite-element programs. The new interface program from the finite-element code MARC also includes the option of using hybrid laminates and allows for variations in temperature fields throughout the component.

Starlinger, A.↗

Challenges and opportunities for the mechanical reliability of metal halide perovskites and photovoltaics

The unproven reliability of perovskite photovoltaics (PVs) is likely to pose an important technical hurdle in the path towards the widespread deployment of the technology. The overall reliability of perovskite PVs is directly afected by the mechanical reliability of the metal halide perovskite material, cells and modules, but this issue has been largely overlooked. Here we stress the importance of addressing the mechanical reliability issue comprehensively. We highlight the important challenges and opportunities, together with best practices, pertaining to the three key interrelated elements that determine the mechanical reliability of perovskite PVs: driving stresses, mechanical properties and mechanical failure. Here, we discuss how to measure the driving stresses and mechanical properties accurately, together with their evolution over time, and the need to understand the relevant failure mechanisms and coupled efects. This efort will inform scientifc approaches to making perovskite PVs more reliable and durable and help them reach their full potential.

14 SOLAR ENERGY↗

Transor analysis

Reliability and failure modes of adaptive restoring circuit module Transor

LOGIC CIRCUIT↗

Photovoltaic fleet degradation insights

Abstract In the PV Fleet Performance Data Initiative, high‐frequency data from commercial and utility‐scale photovoltaic (PV) systems have been collected to examine performance loss rates (PLRs) at a fleet scale. To date, performance data from more than 7.2‐gigawatt (GW) capacity, 1700 sites and 19,000 inverters—approximately equivalent to 6% to 7% of the entire US PV market—have been collected. An overall PLR of −0.75%/year was found, which is in line with historical and recent findings. Tracked silicon (Si) and cadmium telluride (CdTe) performed comparably with all fixed‐tilt systems. Higher PLRs were found for hotter temperature zones; cooler climates exhibit a median −0.48%/year loss, which increases to −0.88%/year in hotter climates. High‐efficiency module technologies showed median PLRs in line with conventional Si technologies but demonstrated markedly different PLR behavior when filtered only for low‐light conditions <600 W/m 2 . Causes for this technology‐dependent behavior are under investigation.

14 SOLAR ENERGY↗

Chapter 11: Combined and Sequential Accelerated Stress Testing for Derisking Photovoltaic Modules

Application of stress factors in the combinations and sequences as they occur in the natural environment better reproduces failures seen in the field. Further, choice of sample type for testing that best represents the final product is most likely to yield relevant results. Tests meeting these criteria are more likely to discover potential weaknesses that are not a priori known in new module designs, reduce risk, accelerate time to market, achieve bankability and reduce costly overdesign.

14 SOLAR ENERGY↗

Experimental Validation of a Module Cell Cracking Model

The What's Cracking app can predict how changes in crystalline silicon photovoltaic (PV) module materials, design, and mounting affect its susceptibility for cell fracture under uniform loading. This work has experimentally validated the app. A set of commercial crystalline silicon PV modules was obtained for this study. The modules were uniformly loaded at three different mounting points, and their subsequent cell fractures were recorded. A large sample size allowed for the development of an experimental statistical model for cell fracture. Here, the comparison of the experiment to predictions from the app is in excellent agreement. Both experimental and modeling results also elucidate how moving the module mounting points toward the center of the module increases the probability of cell fracture.

14 SOLAR ENERGY↗

Evaluation of PV Module Field Performance

This paper describes an effort to inspect and evaluate PV modules in order to determine what failure or degradation modes are occurring in field installations. This paper will report on the results of six site visits, including the Sacramento Municipal Utility District (SMUD) Hedge Array, Tucson Electric Power (TEP) Springerville, Central Florida Utility, Florida Solar Energy Center (FSEC), the TEP Solar Test Yard, and University of Toledo installations. The effort here makes use of a recently developed field inspection data collection protocol, and the results were input into a corresponding database. The results of this work have also been used to develop a draft of the IEC standard for climate and application specific accelerated stress testing beyond module qualification. TEP Solar Test Yard, and University of Toledo installations. The effort here makes use of a recently developed field inspection data collection protocol, and the results were input into a corresponding database. The results of this work have also been used to develop a draft of the IEC standard for climate and application specific accelerated stress testing beyond module qualification. TEP Solar Test Yard, and University of Toledo installations. The effort here makes use of a recently developed field inspection data collection protocol, and the results were input into a corresponding database. The results of this work have also been used to develop a draft of the IEC standard for climate and application specific accelerated stress testing beyond module qualification.

14 SOLAR ENERGY↗

Mathematics of Gas Ingress of Hermetic Packages

Herein, we have derived a gas ingress and egress equation from the first principles of ideal gases. This work is intended to benefit the hermetic microelectronics packaging community, but it may be applied to other fields that require a deep understanding of gas ingress and egress dynamics. The equation outlined herein encompasses package material properties, package characteristics, hermetic testing conditions, and service conditions. It serves as a practical utility for calculating package pressure changes due to gas ingress and egress and, therefore, a power tool for component and system service life predictions.

42 ENGINEERING↗

Tailored approach to study Legionella infection using a lattice light sheet microscope (LLSM)

Legionella is a genus of ubiquitous environmental pathogens found in freshwater systems, moist soil, and composted materials. More than four decades of Legionella research has provided important insights into Legionella pathogenesis. Although standard commercial microscopes have led to significant advances in understanding Legionella pathogenesis, great potential exists in the deployment of more advanced imaging techniques to provide additional insights. The lattice light sheet microscope (LLSM) is a recently developed microscope for 4D live cell imaging with high resolution and minimum photo-damage. We built a LLSM with an improved version for the optical layout with two path-stretching mirror sets and a novel reconfigurable galvanometer scanner ( RGS ) module to improve the reproducibility and reliability of the alignment and maintenance of the LLSM. We commissioned this LLSM to study Legionella pneumophila infection with a tailored workflow designed over instrumentation, experiments, and data processing methods. Our results indicate that Legionella pneumophila infection is correlated with a series of morphological signatures such as smoothness, migration pattern and polarity both statistically and dynamically. Our work demonstrates the benefits of using LLSM for studying long-term questions in bacterial infection. Our free-for-use modifications and workflow designs on the use of LLSM system contributes to the adoption and promotion of the state-of-the-art LLSM technology for both academic and commercial applications.

59 BASIC BIOLOGICAL SCIENCES↗

Stress and Strain Modeling of Low Temperature Cofired Ceramic (LTCC) Seal Frame and Lid

Low temperature cofired ceramic (LTCC) is established as an excellent packaging technology for high reliability, high density microelectronics. LTCC multichip modules (MCMs) comprising both ‘surface mount’ and ‘chip and wire’ technologies provide additional customization for performance. Long term robustness of the packages is impacted by the selection of seal frame and lid materials used to enclose the components inside distinct rooms in LTCC MCMs. An LTCC seal frame and lid combination has been developed that is capable of meeting the sealing and electromagnetic shielding requirements of MCMs. Here, we analyze the stress and strain performance of various seal frame and lid materials, sealing materials, and configurations. The application for the MCM will affect selection of the seal frame, lid, and sealing materials based on this analysis.

36 MATERIALS SCIENCE↗

Thermal design verification testing for the ATS-F and -G spacecraft.

There is a wide fluctuation in the internal power dissipation from the components within the earth viewing module (EVM). The electronic component functional reliability required for a two-to-five year mission is the most significant factor for the thermal design criteria. A mathematical thermal model of the EVM and the orbital environment is used to predict the performance of the thermal control system. Comparisons of the results obtained in chamber thermal balance tests with the data computed on the basis of the theoretical model provide the means for validating the thermal design.

Coyle, M.↗

Development of a flat cable system

A flat conductor cabling system for electrical/electronic interwiring is described. Six major items comprise the system: the cables, splices - one for flat cable to round wires and one for flat cable to flat cable; a series of flat cable connectors; the distributor, which is used for interconnecting the circuits; and a repair technique for the falt cable. Polyarylene, a new high performance melt-processable insulation material, permits the design of a completely standardized, modular flat conductor flat cable. The development of an advanced heat-shrinkable plastics technology involving the use of selectively bonded plastic film has resulted in the multiple termination module, used for making high-reliability sealed solder terminations to either flat conductor cable or round wires. All necessary tools and application equipment are included in the system design.

Neel, R. M.↗

Systems definition summary. Earth Observatory Satellite system definition study (EOS)

A standard spacecraft bus for performing a variety of earth orbit missions in the late 1970's and 1980's is defined. Emphasis is placed on a low-cost, multimission capability, benefitting from the space shuttle system. The subjects considered are as follows: (1) performance requirements, (2) internal interfaces, (3) redundancy and reliability, (4) communications and data handling module design, (5) payload data handling, (6) application of the modular design to various missions, and (7) the verification concept.

Source record↗

Description and status of NASA-LeRC/DOE photovoltaic applications systems

Designed, fabricated and installed were 16 geographically dispersed photovoltaic systems. These systems are powering a refrigerator, highway warning sign, forest lookout towers, remote weather stations, a water chiller at a visitor center, and insect survey traps. Each of these systems is described in terms of load requirements, solar array and battery size, and instrumentation and controls. Operational experience is described and present status is given for each system. The P/V power systems have proven to be highly reliable with almost no problems with modules and very few problems overall.

Ratajczak, A. F.↗

Description and status of NASA-LeRC/DOE photovoltaic applications systems experiments

In its role of supporting the DOE Photovoltaic Program, the NASA-Lewis Research Center has designed, fabricated and installed 16 geographically dispersed photovoltaic systems. These systems are powering a refrigerator, highway warning sign, forest lookout towers, remote weather stations, a water chiller at a visitor center, and insect survey traps. Each of these systems is described in terms of load requirements, solar array and battery size, and instrumentation and controls. Operational experience is described and present status is given for each system. The P/V power systems have proven to be highly reliable with almost no problems with modules and very few problems overall

Ratajczak, A. F.↗

Advanced rotary engine studies

A review of rotary engine developments relevant to a stratified charge rotary aircraft engine is presented. Advantages in module size and weight, fuel efficiency, reliability, and multi-fuel capability are discussed along with developments in turbocharging, increased mean effective pressure, improved apex seal/trochoid wear surfacing materials, and high strength and temperature aluminum casting alloys. A carbureted prototype aircraft engine is also described.

Jones, C.↗