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21.
《Progress in Photovoltaics: Research and Applications》2017,25(12):1059-1067
Space photovoltaics is dominated by multi‐junction (III‐V) technology. However, emerging applications will require solar arrays with high specific power (kW/kg), flexibility in stowage and deployment, and a significantly lower cost than the current III‐V technology offers. This research demonstrates direct deposition of thin film CdTe onto the radiation‐hard cover glass that is normally laminated to any solar cell deployed in space. Four CdTe samples, with 9 defined contact device areas of 0.25 cm2, were irradiated with protons of 0.5‐MeV energy and varying fluences. At the lowest fluence, 1 × 1012 cm−2, the relative efficiency of the solar cells was 95%. Increasing the proton fluence to 1 × 1013 cm−2 and then 1 × 1014 cm−2 decreased the solar cell efficiency to 82% and 4%, respectively. At the fluence of 1 × 1013 cm−2, carrier concentration was reduced by an order of magnitude. Solar Cell Capacitance Simulator (SCAPS) modelling obtained a good fit from a reduction in shallow acceptor concentration with no change in the deep trap defect concentration. The more highly irradiated devices resulted in a buried junction characteristic of the external quantum efficiency, indicating further deterioration of the acceptor doping. This is explained by compensation from interstitial H+ formed by the proton absorption. An anneal of the 1 × 1014 cm−2 fluence devices gave an efficiency increase from 4% to 73% of the pre‐irradiated levels, indicating that the compensation was reversible. CdTe with its rapid recovery through annealing demonstrates a radiation hardness to protons that is far superior to conventional multi‐junction III‐V solar cells. 相似文献
22.
《Organic Electronics》2014,15(9):2059-2067
Polymer solar cells (PSCs) are of great interest in the past decade owing to their potentially low-cost in the manufacturing by the solution-based roll to roll method. In this paper, a novel inverted device structure was introduced by inserting a high conductive PEDOT:PSS (hcPEDOT:PSS) layer between the Au nanoparticles (NPs)-embedded hole transport layer (PEDOT:PSS) and the top electrode layer. Power conversion efficiency (PCE) initially reached up to 4.51%, illustrating ∼10% higher compared with the device similarly enhanced by Au NPs plasmonics where only one PEDOT:PSS layer with the embedded Au NPs was used in single bulk heterojunction inverted PSCs based on the poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methylester (P3HT:PCBM). The PCE was further improved from 4.51% to 5.01% by adding the high-boiling point solvent of 1,8-diiodooctane (DD) into the active layer, presenting ∼20% enhancement in PCE through dual effects of introducing the high boiling point solvent and the high conductive PEDOT:PSS layer. Morphologies of the active layers were characterised by SEM and AFM separately in the paper. 相似文献
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针对小型光伏微电网系统由于受投资成本限制造成的经济性差、能源利用手段单一以及监控系统功能不完整的问题,设计了一种基于光电光热一体化(Photovoltaic-photothermal, PVPT或PV/T)技术的简单改进方案。并在此基础上探讨了基于前端组件温度-功率关系的混合控制方法的可行性。利用PVPT原理的优点综合提升小型光伏微电网系统的整体经济效益。实验结果表明,改进方案能有效地增加系统的发电效率,丰富用户的光能利用手段。而以此改进方案为基础的混合温度功率控制方法调控过程平滑,调控区间较小,可作为小型光伏微电网系统的后备控制和功率微调控制。由于该改进方法成本较低、结构简单,满足小型光伏微电网系统运营特点的要求,具有一定的应用潜力。 相似文献
25.
针对目前光伏发电过程中由于"弃光"现象导致能源利用率低和经济性差等问题,提出一种基于XGBoost算法融合多种特征的短期光伏发电量预测的方法。文中介绍了XGBoost算法的基本原理,引入正则化惩罚函数和误差函数来构建光伏预测模型的目标函数;分析了光伏发电量和各特征之间的皮尔森相关系数,同时对特征的异常数据进行预处理。在训练过程中为了避免对模型超参数的影响,采用K折交叉验证(K Fold Cross Validation)对数据的训练集、验证集和测试集进行划分。训练完模型参数后把测试集数据放到光伏预测模型中,预测得到未来三天的光伏发电量。对比实验选择SVM和LSTM两种预测方法进行,实验结果表明XGBoost算法在预测光伏发电中具有较高的准确性和实用性。 相似文献
26.
本文推导了在外加e-偏振非相干均匀背景光照下开路光伏光折变晶体中的亮空间孤子的演化方程,给出了方程的数值积分形式的解,并且得到了小振帐条件下亮孤子解析角以及孤子宽度的解析表达式,本文还讨论了外加e-偏振非相干均匀背景光对开路光伏孤子的影响,结果表明,若外加e-偏振非相干均匀背景光的强度远远大于晶体的暗辐照强度,则不利于开路光伏孤子的形成。ee 相似文献
27.
Alberto Jimnez‐Solano Jos‐Maria Delgado‐Snchez Mauricio E. Calvo Jos M. Miranda‐Muoz Gabriel Lozano Diego Sancho Emilio Snchez‐Cortezn Hernn Míguez 《Progress in Photovoltaics: Research and Applications》2015,23(12):1785-1792
Herein, we present a prototype of a photovoltaic module that combines a luminescent solar concentrator integrating one‐dimensional photonic crystals and in‐plane CuInGaSe2 (CIGS) solar cells. Highly uniform and wide‐area nanostructured multilayers with photonic crystal properties were deposited by a cost‐efficient and scalable liquid processing amenable to large‐scale fabrication. Their role is to both maximize light absorption in the targeted spectral range, determined by the fluorophore employed, and minimize losses caused by emission at angles within the escape cone of the planar concentrator. From a structural perspective, the porous nature of the layers facilitates the integration with the thermoplastic polymers typically used to encapsulate and seal these modules. Judicious design of the module geometry, as well as of the optical properties of the dielectric mirrors employed, allows optimizing light guiding and hence photovoltaic performance while preserving a great deal of transparency. Optimized in‐plane designs like the one herein proposed are of relevance for building integrated photovoltaics, as ease of fabrication, long‐term stability and improved performance are simultaneously achieved. © 2015 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd. 相似文献
28.
Francisco Gallego‐Gómez Eva M. García‐Frutos José M. Villalvilla José A. Quintana Enrique Gutierrez‐Puebla Angeles Monge María A. Díaz‐García Berta Gómez‐Lor 《Advanced functional materials》2011,21(4):738-745
A new carbazole‐related small molecule exhibiting self‐assembly into ordered nanostructures in solution‐processed cast films has been synthesized and its charge‐photogeneration and ‐transport properties have been investigated. Large photoconductivity was measured in the amorphous state while an enormous improvement in the photoconduction properties was observed when the molecules spontaneously organized. Photocurrents increased upon self‐assembly by up to four orders of magnitude, mostly due to the drastic enhancement of the charge photogeneration. A greatly favorable arrangement of the aromatic cores in the resulting nanostructures, which were characterized by X‐ray analysis, may explain these improvements. Photocurrents of mA cm?2, on/off ratios of 104 and quantum efficiencies of unity at low field and light intensity, which are among the best values reported to date, along with the simplicity of fabrication, give this readily‐available organic system great potential for use in plastic optoelectronic devices. 相似文献
29.
阐述了两级式光伏并网发电控制系统的结构及其控制过程,建立了光伏阵列模型和光伏并网发电系统模型,利用光伏阵列模型模拟了光照条件变化时光伏并网系统的输出情况进行仿真分析。实验表明,此两级式光伏并网发电系统能迅速有效地跟踪到光伏阵列的最大功率点,而且能够控制并网电流的波形,使逆变器的输出电流与电网电压同频同相,保证电流输出波形为正弦波。 相似文献
30.