【作者】 高健；

【导师】 周求湛；

【作者基本信息】 吉林大学 ， 通信与信息系统， 2012， 硕士

【摘要】 随着太阳能电池在人类社会的广泛应用，尤其是作为供电系统的重要组成部分应用于在轨运行的空间站、宇宙飞船以及人造卫星等高端应用领域，并且这些实际应用环境与太阳能电池的生产测试环境相比差别较大，因此自太阳能电池问世以来，其可靠性研究一直在持续进行。低频噪声作为一种高效、无损的方法，一直是半导体器件可靠性研究的重要工具之一。低频噪声源于半导体器件内部载流子的无规则运动，不可避免，而过激低频噪声则是表征器件可靠性的重要指标。目前，已经发现太阳能电池中存在的过激噪声有1/f噪声，G-R噪声，RTS噪声以及猝发噪声，其中后三种类型的低频噪声在频域均表现为G-R谱，而RTS噪声与猝发噪声则在时域上表现为明显的持续时间不同而幅度相近的脉冲序列。虽然，国内外对于基于低频噪声的太阳能电池可靠性筛选有了初步的研究，但通过阅读大量的文献发现，目前研究还存在如下问题：(1)对于太阳能电池的低频噪声有了一定的认识，但是却未研究其实际的电信号表现形式，及其对短路电流与开路电压这两个重要参数的影响，未建立一个适用于全面分析太阳能电池噪声特性的模型；(2)没有对太阳能电池电流噪声和电压噪声的提取方法进行研究，进而没有提出一种综合这两种噪声的可靠性筛选方法；(3)对于广泛应用的太阳能电池组件的可靠性研究还仅限于目测，或测量开路电压、短路电流等参数以及长时间的应力实验等方式，而基于低频噪声这种无损、方便、高效的可靠性评估方法研究甚少；(4)对于实际应用的太阳能电池组件，其噪声参数的研究目前仍是空白。因此，基于低频噪声对于短路电流和开路电压的影响，构建太阳能电池的E_n-I_n噪声模型并对噪声参数进行提取，综合考虑测得的各噪声参数，对太阳能电池进行可靠性筛选，并在模型的基础上对组件的噪声参数进行研究，以便实现对组件进行基于低频噪声的可靠性评估的研究。因此，本课题从以下几个方面进行研究：(1)提取太阳能电池的等效二端口网络并构建其E_n-I_n噪声模型根据太阳能电池的等效电路，提取太阳能电池的等效二端口网络；分析太阳能电池的低频噪声类型及其噪声产生机理，以电流噪声源与电压噪声源这两种形式，合理地将太阳能电池的内部噪声源等效到二端口网络输出端，构建太阳能电池的E_n-I_n噪声模型。(2)研究太阳能电池E_n-I_n模型的噪声参数提取及测试方案根据二端口网络理论，将太阳能电池内部或表面缺陷引起的噪声功率等效到输出端，研究噪声模型的电流噪声参数与电压噪声参数与输出噪声功率的关系，得到两个噪声参数的提取方法；从而依据噪声参数的提取方法确定实际的测试电路。(3)研究太阳能电池的可靠性筛选方法对太阳能电池的电流噪声功率谱与电压噪声功率谱进行谱成分分析，提取1/f谱成分的频率范围与频率指数，G-R谱成分的转折频率与幅度，提取1/f谱频率范围内随偏置条件变化最敏感的频率点与G-R谱幅度作为两个敏感参数对太阳能电池进行可靠性筛选分类；考虑到这两种点频噪声信息表征不完整性，为了得到更加细致准确的筛选分类结果，从全频段分析噪声功率谱，将Gower相似系数作为敏感参数，采用逐步分类的方法进行可靠性筛选分类。(4)研究双电池连接的简单太阳能组件的噪声参数计算方法本设计仅考虑以只有两个太阳能电池单体按照串联、并联这两种基本连接形式构成的简单组件，分别研究了这两种形式组件网络噪声参数的计算方法，进而得到一般性规律，为复杂组件的噪声特性研究做铺垫。更多还原

【Abstract】 With the wide application of solar cells in human society, especially as an importantpart of the power supply system used in the field of high precision, such as the orbit spacestation, spacecraft and satellites and other spacecraft power supply and the environment isvery different from that in which solar cells are produced and tested, since solar cells are putinto use, the research on their reliability study is always ongoing.Low-frequency noise as an efficient, non-destructive method has been used as an im-portant tool for the reliability analysis of semiconductor devices. Low-frequency noise gen-erates from the irregular movement of the internal carrier in semiconductor device, and isinevitable. It has been obtained that the extreme low-frequency noise is an important indica-tor of the characterization of device reliability. At present, it has been found that the maintypes of extreme noise existed in the solar cell are1/f noise, GR noise, RTS noise and burstnoise, and the latter three types of low-frequency noise in the frequency domain expressed asthe G-R spectrum, while the RTS noise and burst noise are specially expressed as pulse se-quences made up with different duration and same amplitude pulsed in the time domain.Although the reliability screening methods of solar cells based on low-frequency noisefilter have some preliminary researches, there still exits some problems as follows to besolved from reading the extensive literature:(1) although there is a certain understanding ofthe low-frequency noise in solar cells, the what shape the noise signal expresses as, voltageor current, have not been studied, and also how the different shape noise in solar cells disturbits two important parameters which are short-circuit current and open-circuit voltage, the es-tablishment of a noise model for solar cells is needed;(2) the extraction method of voltagenoise and current noise in solar cells has not been studied;(3) for the reliability study of thewidely used solar modules is limited to visual observation, or measurement of parameterssuch as the open circuit voltage, short circuit current and a long period of stress experiments,while the non-destructive, convenient, efficient method based on low-frequency noise forsolar cells reliability estimation are little studied;(4) it is still blank in the field of noise pa-rameters study of the solar modules which are common used in practical applications.Therefore, considering the short-circuit current and open circuit voltage influenced by the low-frequency noise in solar cells, establish the E_n-I_n noise model and extract its noiseparameters, comparing all the measured noise parameters, study the reliability screeningmethod, and study the noise parameters of solar cell modules with the basis of the single so-lar cell noise model in order to obtain the modules reliability assessment method based onthe low-frequency noise, which is essential. Therefore, the following aspects are studied inthis paper:(1) Build the equivalent two-port network of the solar cells and extract the E_n-I_n noisemodelBuild the equivalent two-port network of solar cells according to the solar cells equiva-lent circuit; analyze the low-frequency noise types of the solar cells and the noise generationmechanisms, then obtain the two-port network in which the internal noise sources areequivalent to the output as the forms of current noise source and voltage noise source, at last,extract the E_n-I_n noise model of solar cells.(2) Study the extraction and measurement methods of parameters of solar cell E_n-I_nnoise modelConsidering the noise power caused by the internal or surface defects in solar cells isequivalent to the output noise power according to the two-port network theory, study the re-lationship between the noise parameters of current noise and voltage noise and the outputnoise power, then obtain the two noise parameter extraction methods; design the actual testcircuits based on the noise parameter extraction methods.(3) Study the reliability screening methods of the solar cellAnalysis the components of the current noise power spectrum and voltage noise powerspectrum, extract the frequency range and frequency index of1/f spectral composition andthe corner frequency and amplitude of G-R spectral composition. Then find the characteristicfrequency-point noise and the full-band frequency parameter as the basis for solar cells reli-ability screening. The most sensitive frequency point in the1/f spectrum frequency band andthe G-R spectrum amplitude are chosen as the two sensitive parameters for the reliabilityscreening and sorting; while take into account that the above two point-frequency noise cannot represent information completely, so in order to get more detailed and accurate sortingresults, the Gower similarity coefficient is chosen as a sensitive parameter of the full fre-quency band, and use the one by one classification method for the reliability of sorting.(4) Study the calculation method of noise parameters in the simple dual-connected solarcell modules This paper only considers the simple components composed of only two solar cellsconnected with the form of series or parallel, study the methods of the network noise pa-rameters calculation methods respectively, and then obtain the general law for the furtherstudy of the complex solar cell modules’ noise characteristics.更多还原