- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Effect of short-circuit stress on the degradation of the SiO2 dielectric in SiC power MOSFETs
摘要： This paper presents the impact of a short-circuit event on the gate reliability in planar SiC MOSFETs, which becomes more critical with increased junction temperature and higher bias voltages. The electrical waveforms indicate that a gate degradation mechanism takes place, showing a large gate leakage current that increases as the gate degrades more and more. A failure analysis has been performed on the degraded SiC MOSFET and then compared to the structure of a new device to identify possible defects/abnormalities. A Focused-Ion Beam cut is performed showing a number of differences in comparison to the new device: (i) cracks between the poly-silicon gate and aluminium source, (ii) metal particles near the source contact, and (iii) alterations in the top surface of the aluminium source. The defects have been correlated with the increase in gate-leakage current and drain-leakage current.
关键词： Focused-Ion Beam,Short circuit,Gate-oxide breakdown,Gate oxide,Degradation,Defects,Reliability,SiC MOSFET,Failure analysis,SEM
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE Power & Energy Society General Meeting (PESGM) - Portland, OR, USA (2018.8.5-2018.8.10)] 2018 IEEE Power & Energy Society General Meeting (PESGM) - Study of Impact of Cloud Distribution on Multiple Interconnected Solar PV Plants Generation and System Strength
摘要： Dependence of solar power generation on solar irradiance results in sudden and dramatic variations in power generation following significant changes in cloud distribution over a solar PV plant. Currently, this phenomenon is being one of the most challenging issues in resource planning and maintaining the reliability of modern power grids with high penetration of solar power. The dramatic variation of solar power generation has a direct impact on system strength at the Points of Interconnection (POIs). Hence, the power quality of the system is compromised, especially because solar PV plants are usually interconnected to distribution systems and near load zones. In this paper, an Artificial Neural Network (ANN) based approach is developed to forecast the clouds distribution for the estimation of sudden and dramatic variations in the solar irradiance. This estimate is used to evaluate the system strength in terms of voltage stability at each POI. We apply newly developed methodology to measure the system strength known as Site-Dependent Short Circuit Ratio (SDSCR), which provides more accurate results of system strength evaluation. The validity and effectiveness of the developed approach is confirmed through comparing its results versus the cloud distribution data provided by weather satellites.
关键词： Artificial neural network,renewable energy,system strength,voltage stability,short circuit ratio
更新于2025-09-23 15:22:29
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[IEEE 2018 Second International Conference on Computing Methodologies and Communication (ICCMC) - Erode (2018.2.15-2018.2.16)] 2018 Second International Conference on Computing Methodologies and Communication (ICCMC) - A STUDY ON MODELING AND SIMULATION OF PHOTOVOLTIC ARRAYS USING SINGLE DIODE METHOD
摘要： This paper presents a method of modeling and simulation of photovoltaic arrays. The main objective of this study is to achieve a circuit based simulation model of a photovoltaic cell and to scrutinize the results and compare them with respect to change in environmental parameters like irradiation and temperature. The proposed method of single diode model is implemented in MATLAB software based on the particular environmental condition. And on the basis of this study simulation results and ideal theoretical values are compared.
关键词： Renewable energy sources,MATLAB software,PV system,Single diode method,Open circuit current and short circuit voltage
更新于2025-09-23 15:21:01
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Failure analysis of 650?V enhancement mode GaN HEMT after short circuit tests
摘要： The paper presents the results of a post failure analysis performed on commercial 650 V GaN power HEMT after short circuit destructive tests. The used experiment set up includes a protection circuit able to avoid the explosion of the sample during the test. Moreover, it limits the energy involved in the failure and facilitates the identification of the areas where the failure is initiated. The post failure analysis confirms that DUTs exhibit two kinds of failures. In the first failure mode, for which large energies are dissipated in the device before the failure, the damaged area of the chip is quite large and is located close to external drain contacts. In this area, very likely, the temperature exceeds the melting temperature of the metallization. The second failure mode is observed for higher values of the drain voltage and involves lower energies dissipated in the DUT during SC before the failure. In this case, the damaged area is very small and is located below the source field plate at gate edge on the drain side. 2D finite element simulations show that in this region the dissipated power density becomes very high and can cause the local temperature to exceed the temperature limit of GaN/AlGaN structure.
关键词： GaN power HEMT,Short circuit,Failure analysis
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Distribution Feeder Fault Comparison Utilizing a Real-Time Power Hardware-in-the-Loop Approach for Photovoltaic System Applications
摘要： Power outages are a challenge that utility companies must face, with the potential to affect millions of customers and cost billions in damage. For this reason, there is a need for developing approaches that help understand the effects of fault conditions on the power grid. In distribution circuits with high renewable penetrations, the fault currents from DER equipment can impact coordinated protection scheme implementations so it is critical to accurately analyze fault contributions from DER systems. To do this, MATLAB/Simulink/RT-Labs was used to simulate the reduced-order distribution system and three different faults are applied at three different bus locations in the distribution system. The use of Real-Time (RT) Power Hardware-in-the-Loop (PHIL) simulations was also used to further improve the fidelity of the model. A comparison between OpenDSS simulation results and the Opal-RT experimental fault currents was conducted to determine the steady-state and dynamic accuracy of each method as well as the response of using simulated and hardware PV inverters. It was found that all methods were closely correlated in steady-state, but the transient response of the inverter was difficult to capture with a PV model and the physical device behavior could not be represented completely without incorporating it through PHIL.
关键词： faults,photovoltaic inverter,short-circuit analysis,hardware-in-the-loop
更新于2025-09-23 15:19:57
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Determination of the series resistance of a solar cell through its maximum power point
摘要： A simple analytical approach has been developed to determine the series resistance, Rs, of a solar cell. The method adopted here depends only on the knowledge of the open-circuit voltage, Voc, and the current and voltage at the maximum power point, Isc and Vmp respectively. This approach, based on a knowledge of these operating output parameters of the cell, provides a theoretical framework for an existing computer simulated approach which has been widely used in industries.
关键词： series resistance,short-circuit current,five-parameter model,light generated current,solar cell,shunt resistance
更新于2025-09-23 15:19:57
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[IEEE 2018 International conference on Computing, Electronic and Electrical Engineering (ICE Cube) - Quetta, Pakistan (2018.11.12-2018.11.13)] 2018 International Conference on Computing, Electronic and Electrical Engineering (ICE Cube) - Impact of PV Penetration on Short Circuit Current of Radial Distributed Feeder and Existing Power System Protection of NUST
摘要： Integration of distributed generation into existing network can solve the problem of increasing energy demand which is due to exponential growth in world population. Integration of distributed generation has increased due to its immense advantages like low loading of transmission network, improvement in voltage profile and decrease in line losses. Despite of many advantages distributed generation also poses various adverse effects on network like harmonics, network protection, frequency instability and increase in short-circuit current level. However, it is difficult to eliminate the fault behavior due to dispersed nature of distributed generation that might affect the performance of power system protection. This is due to the change in power flow and magnitude of fault current. In this paper the effect of distributed generation on fault current level and protection of radial distribution feeder of National University of Science and Technology is studied. Three phase fault is simulated and analyzed for radial distribution network of National University of Science and Technology in MATLAB Simulink.
关键词： short circuit current,distribution system,three phase fault,PV penetration,MV distributed network,Distributed generation
更新于2025-09-19 17:15:36
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[IEEE 2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN) - Zagreb, Croatia (2019.7.2-2019.7.5)] 2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN) - Implement of 100-Gbps optical transceiver firmware for optical communication systems
摘要： This paper proposes a new fast technique, in which the slope of a photovoltaic (PV) inverter current is utilized to predict if the current is expected to exceed its rated value due to any grid faults. Two applications of this technique are demonstrated. In jurisdictions where grid codes require distributed generators (DGs) to disconnect after a fault occurrence, such as in Ontario, Canada, this technique is utilized to rapidly disconnect the PV solar system even before the inverter short circuit current actually exceeds the rated current of the inverter, thereby obviating the problem of any adverse short circuit current contribution into the grid. However, in regions where grid codes require DGs to stay connected and provide grid support, such as low-voltage ride through, this technique can be used to rapidly and autonomously transform the PV solar farm into a dynamic reactive power compensator STATCOM (termed PV-STATCOM) for providing voltage support function. In this paper, the PV-STATCOM is used to stabilize a critical induction motor load in the vicinity of the solar farm, which would have otherwise become unstable due to the grid fault. PSCAD-based simulation studies are performed on a realistic distribution network to demonstrate the effectiveness of this technique.
关键词： STATCOM,Distributed generator (DG),inverter,flexible AC transmission system (FACTS),protection,short circuit current,PV-STATCOM,photovoltaic (PV) systems
更新于2025-09-19 17:13:59
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Record Photocurrent Density over 26a??mAa??cm <sup>a??2</sup> in Planar Perovskite Solar Cells Enabled by Antireflective Cascaded Electron Transport Layer
摘要： Here an antireflective cascaded SnO2/TiO2-Cl electron transport layer (ETL) is devised to enhance the performance of planar perovskite solar cells (PSCs). The primary optical reflection of planar PSCs at the front side can be dramatically reduced by using cascaded ETL. Based on this strategy, we achieved a record-high short-circuit current density of 26.1 mA cm-2 and a high PCE of 22.9% in FAPbI3-based planar PSCs.
关键词： planar perovskite solar cells,cascaded electron transport layers,anti-reflection,bilayer,short-circuit current density
更新于2025-09-19 17:13:59
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Boosting ultrathin aSi-H solar cells absorption through a nanoparticle cross-packed metasurface
摘要： Hydrogenated amorphous silicon (a-Si:H) solar cells have some performance limitations related to the mobility and lifetime of their carriers. For this reason, it is interesting to explore thin-film solutions, achieving a tradeoff between photons optical absorption and the electrical path of the carriers to get the optimum thickness. In this work, we propose the insertion of a metasurface based on a cross-patterned ITO contact film, where the crosses are filled with nanospheres. We numerically demonstrate that this configuration improves the photogenerated current up to a 40% by means of the resonant effects produced by the metasurface, being independent on the impinging light polarization. Light handling mechanisms guide light into the active and auxiliary layers, increasing the effective absorption and mitigating the Staebler-Wronski effect. The selection of optimum materials and parameters results in nanospheres of ZnO with a 220 nm radius.
关键词： a-Si hydrogenated solar cell,Short-circuit current,Metasurface,Absorption enhancement,Nanostructure
更新于2025-09-19 17:13:59