一种提取太阳电池参数新方法

提出一种提取太阳电池光生电流、反向饱和电流、理想因子、串联电阻和并联电阻等5个参数的新方法。通过引入Lambert-W函数显化太阳电池电流-电压(I-V)特性方程,对光照I-V数据进行非线性全局拟合,从而获得太阳电池的光生电流等5个待定参数值。实验表明,待定参数的拟合结果具有较高准确性。     

太阳电池基本参数的实验与分析

通过对太阳电池在光照时等效电路的电路方程进行推导,得到了太阳电池在光照条件下串联电阻和分流电阻的数学表达式.根据实际测得的硅太阳电池伏安特性曲线和输出功率曲线,对其串联电阻与分流电阻进行了推算.     

GaAs异质面太阳电池光谱响应和暗J-V特性的拟合分析

本文用LPE法制备了GsAs异质面太阳电池,测量了电池的光谱响应(SR)和暗J—V特性,推导了它们的理论公式,用这些理论公式对测量值进行了曲线拟合。从SR拟合求得三个区的少子扩散长度、AlGaAs层厚度、结深、前表面和界面复合速度等七个结构参数。从暗∫—V特性拟合求得扩散电流密度分量、复合电流密度分量、结品质因子和串并联电阻等五个电学参数。最后分析拟合结果,讨论了这些参数对电池效率的影响,提出提高效率的方法。     

纳米硅/晶体硅异质结电池的暗Ⅰ-Ⅴ特性和输运机制

采用HWCVD技术在p型CZ晶体硅衬底上制备了纳米硅/晶体硅异质结太阳电池,测量了晶体硅表面在不同氢处理时间下的异质结的暗Ⅰ-Ⅴ特性和相应的电池性能参数.室温下的正向暗Ⅰ-Ⅴ特性采用双二极管模型来拟合,可将0～1V的电压范围区分为4个区域:旁路电阻(0～0.15V)、非理想二极管2(0.15～0.3V)、理想二极管1(0.3～0.5V)和串联电阻(>0.5V).拟合结果表明,适当的氢处理时间(～30s)可有效降低非理想二极管的理想因子n2,即降低界面复合电流,表明具有好的界面特性.对于282～335K的暗Ⅰ-Ⅴ温度特性的研究表明,在0.15～0.3V的低电压范围,暗电流主要由耗尽区的复合电流提供,0.3～0.5V电压范围,对输运起主要作用的是隧穿过程,该过程可用通过界面陷阱能级的隧穿模型来解释.     

纳米硅/晶体硅异质结电池的暗Ⅰ-Ⅴ特性和输运机制

采用HWCVD技术在p型CZ晶体硅衬底上制备了纳米硅/晶体硅异质结太阳电池,测量了晶体硅表面在不同氢处理时间下的异质结的暗Ⅰ-Ⅴ特性和相应的电池性能参数.室温下的正向暗Ⅰ-Ⅴ特性采用双二极管模型来拟合,可将0～1V的电压范围区分为4个区域:旁路电阻(0～0.15V)、非理想二极管2(0.15～0.3V)、理想二极管1(0.3～0.5V)和串联电阻(>0.5V).拟合结果表明,适当的氢处理时间(～30s)可有效降低非理想二极管的理想因子n2,即降低界面复合电流,表明具有好的界面特性.对于282～335K的暗Ⅰ-Ⅴ温度特性的研究表明,在0.15～0.3V的低电压范围,暗电流主要由耗尽区的复合电流提供,0.3～0.5V电压范围,对输运起主要作用的是隧穿过程,该过程可用通过界面陷阱能级的隧穿模型来解释.     

提取太阳电池参数的解析方法和显函数方法的研究

对提取太阳电池参数的解析和显函数两种方法进行了比较研究。结果表明,两种方法均可以正确拟合太阳电池电流-电压特性,显函数方法的拟合精度比解析方法高约1倍,而解析方法的运行时间约是显函数方法的1%。在解析方法中,最大功率点选取将影响拟合参数的结果;而显函数方法,初始值的选取将影响太阳电池参数的拟合结果,选择合适的初始值可以大大提高太阳电池参数的拟合精度。     

3 nm环栅场效应管射频小信号等效电路模型

针对3 nm环栅场效应晶体管,提出了一种射频小信号等效电路模型及基于有理函数拟合的解析模型参数提取方法。首先,在关态条件下提取不受偏置影响的非本征栅/源/漏极电阻、栅到源/漏电容、衬底电容和电阻。然后,在不同偏置条件下提取受偏置影响的本征模型参数。使用Sentaurus TCAD和Matlab对器件进行仿真并拟合得到相关参数,在ADS中验证等效电路模型。结果表明,在10 MHz~300 GHz频率范围内,TCAD仿真与等效电路仿真S参数的最大误差低于2.69%,证实了所建立模型及建模方法的准确性。该项研究成果对射频集成电路设计具有参考价值。     

Cu(In1-xGax)Se2薄膜太阳电池的J-V特性

对Cu(In1-xGax)Se2(CIGS)太阳电池J-V特性曲线进行了测试和分析,采用Matlab软件进行计算,得到电池的二极管品质因子、反向饱和电流密度、串联电阻、并联电阻等特性参数.采用数值逼近法,将得到的参数回归J-V方程,与测试结果符合较好.对不同光照强度下电池的特性参数进行计算,发现并联电阻随光照强度增加而降低,并分析了原因.     

Ⅲ-Ⅴ族化合物HBT模型参数提取

对Ⅲ-Ⅴ族化合物HBT模型本征集电极和发射极电流方程进行了改进,加强了模型的拟合能力.给出了HBT在零偏和冷偏下的等效电路模型,为精确提取基-射、基-集结本征和外围结电容,开发出一种新的、从零偏条件下测量所得S参数中直接提取本征、外部结电容的方法,该方法同时允许本征集电极电阻(Rci)的解析提取.运用该方法精确提取了一发射结面积为180μm2的GaAs HBT器件参数,验证结果表明,算法精度可达40GHz.     

Ⅲ-Ⅴ族化合物HBT模型参数提取

对Ⅲ-Ⅴ族化合物HBT模型本征集电极和发射极电流方程进行了改进,加强了模型的拟合能力.给出了HBT在零偏和冷偏下的等效电路模型,为精确提取基-射、基-集结本征和外围结电容,开发出一种新的、从零偏条件下测量所得S参数中直接提取本征、外部结电容的方法,该方法同时允许本征集电极电阻(Rci)的解析提取.运用该方法精确提取了一发射结面积为180μm2的GaAs HBT器件参数,验证结果表明,算法精度可达40GHz.     

Cu(In1-xGax)Se2薄膜太阳电池的J-V特性

对Cu（In1-xGax）Se2（CIGS）太阳电池J-V特性曲线进行了测试和分析,采用Matlab软件进行计算,得到电池的二极管品质因子、反向饱和电流密度、串联电阻、并联电阻等特性参数，采用数值逼近法,将得到的参数回归J-V方程,与测试结果符合较好，对不同光照强度下电池的特性参数进行计算,发现并联电阻随光照强度增加而降低,并分析了原因。     

Detailed Analysis of Temperature Characteristics of an InGaP/InGaAs/Ge Triple-Junction Solar Cell

Temperature characteristics of an InGaP/InGaAs/Ge triple-junction solar cell were analyzed in detail using an equivalent circuit calculation. The current–voltage (I–V) characteristics of single-junction solar cells (InGaP, InGaAs, Ge solar cells) were measured at various temperatures. Fitting of I–V curves between measured and calculated data was carried out, and the diode parameters and temperature exponents of the single-junction solar cells were extracted. The parameters for each single-junction solar cell were used in the equivalent circuit model for the triple-junction solar cell, and calculations of solar cell performance were carried out. Measured and calculated results of the I–V characteristics at various temperatures agreed well.     

Explanation for the dark I–V curve of III–V concentrator solar cells

The measurement of the dark I–V curve is one of the most straightforward methods for characterizing solar cells. Consequently, an accurate knowledge of its meaning is of high relevance for the comprehension and technological feedback of these devices. In this paper, an explanation of the dark I–V curve for concentrator III–V solar cells is presented using a 3D (three‐dimensional) model in order to provide a proper data fit that provides meaningful physical parameters that are also compatible and coherent with a data fit from illumination curves. The influence on the dark I–V curve of the most significant series resistance components of concentrator solar cells is also analysed concluding that only the vertical component as well as the front contact‐specific resistance can be assessable by means of this characterization method while both emitter and metal sheet resistances cannot be detected. For comparison purposes, the same experimental data have been fitted by means of a traditional two‐diode model showing that, although an accurate dark I–V curve fitting can be achieved, the extracted parameters are unable to reproduce illumination data since lumped models assume the same ohmic losses distribution for both dark and illumination conditions. Copyright © 2007 John Wiley & Sons, Ltd.     

CdTe/CdS多晶薄膜太阳能电池正向电流的计算机模拟分析

应用数值方法来解CdTe／CdS异质结J－V特性，进而得出其二极管理想因子、激活能以及异质结空间电荷区党度。结果表明，CdTe一侧空间电荷区复合是主导CdTe／CdS异质结传输电流的主要机制。说明在CdTe基太阳能电池制造中，控制多晶薄膜化学缺陷对提高电池能量转换效率的重要意义。     

太赫兹平面肖特基二极管参数模型

根据太赫兹平面肖特基二极管物理结构,在理想二极管SPICE参数模型的基础上建立了二极管小信号等效电路模型。依据该二极管等效电路模型设计了基于共面波导（CPW）去嵌方法的二极管S参数在片测试结构,并对其在0.1~50 GHz、75~110 GHz频率范围内进行了高频小信号测试,利用测试结果提取了高频下二极管电路模型中各部分电容、电阻以及电感参数。将相应的高频下电容与电阻参数分别与低频经验公式电容值和直流I-V测试提取的电阻值进行了对比,并利用仿真手段对高频参数模型进行了验证。完整的参数模型以及测试手段相较于理想二极管SPICE模型和传统的参数提取方法可以更为准确地表征器件在高频下的工作状态。该建模思路可用于太赫兹频段非线性电路的优化设计。     

Fill factor analysis of solar cells' current–voltage curves

After completion of the solar cell manufacturing process the current–density versus voltage curves (J(U) curves) are measured to determine the solar cell's efficiency and the mechanisms limiting the efficiency. An accurate and robust analysis of the measured curves is essential. In this work it is shown that fitting the two‐diode model is inappropriate to quantify recombination in the space charge region and ohmic losses due to series resistance. Three fill factors, namely the fill factor of the illuminated J(U) curve, the pseudo fill factor of the sunsVoc curve and the ideal fill factor of the single diode model, are the base of a quick loss analysis that is evaluated in the present paper. It is shown that for an accurate analysis the distributed character of the series resistance and the network character of the solar cell cannot be neglected. An advanced current–voltage curve analysis including fill factors and fit is presented. Copyright © 2010 John Wiley & Sons, Ltd.     

Numerical simulation of tunnel diodes for multi‐junction solar cells

This work presents efforts to simulate numerically the current voltage (IV) curve of a III–V based Esaki tunnel diode. Using a tunneling model, which takes into account the full nonlocality of the barrier, a good agreement between measured and simulated IV curves of a GaAs tunnel diode was achieved. The influence of a series resistance effect as well as the importance of trap assisted tunneling (TAT) could be shown. In addition, we present a two‐dimensional model of a III–V multi‐junction solar cell including the numerical model of the investigated Esaki tunnel diode. Copyright © 2008 John Wiley & Sons, Ltd.     

纳米硅/晶体硅异质结电池的暗I-V特性和输运机制

采用HWCVD技术在P型CZ晶体硅衬底上制备了纳米硅／晶体硅异质结太阳电池,测量了晶体硅表面在不同氢处理时间下的异质结的暗I-V特性和相应的电池性能参数．室温下的正向暗I-V特性采用双二极管模型来拟合,可将0～1V的电压范围区分为4个区域：旁路电阻（0～0．15V）、非理想二极管2（0．15～0．3V）、理想二极管1（0．3～0．5V）和串联电阻（〉0．5V）．拟合结果表明,适当的氖处理时间（～30s）可有效降低非理想二极管的理想因子n2,即降低界面复合电流,表明具有好的界面特性．对于282～335K的暗I—V温度特性的研究表明,在0．15～0．3V的低电压范围,暗电流主要由耗尽区的复合电流提供,0．3～0．5V电压范围,对输运起主要作用的是隧穿过程,该过程可用通过界面陷阱能级的隧穿模型来解释．     

Improved equivalent circuit and analytical model for amorphoussilicon solar cells and modules

An improved equivalent circuit for hydrogenated amorphous silicon (a-Si:H) solar cells and modules is presented. It is based on the classic combination of a diode with an exponential current-voltage characteristic, of a photocurrent source plus a new term representing additional recombination losses in the i-layer of the device. This model/equivalent circuit matches the I(V) curves of a-Si:H cells over an illumination range of six orders of magnitude. The model clearly separates effects related to the technology of the device (series and parallel resistance) and effects related to the physics of the p-i-n junction (recombination losses). It also allows an effective μτ product in the i-layer of the device to be determined, characterizing its state of degradation