双层氮化硅薄膜对晶硅太阳电池性能的影响

利用管式PECVD在晶硅太阳电池上制备3种不同结构的Si Nx∶H减反射膜:第一子层(靠近基底硅)折射率大于第二子层的双层减反射膜、第一子层折射率小于第二子层的双层减反射膜、单层减反射膜。通过光学和电学性能的比较可看出,第一种类型太阳电池的短路电流、开路电压和电池效率的分布区间均相对集中,其短路电流和开路电压均高于其他样品。该结果主要归结于该类型双层Si Nx∶H减反射膜不但光学匹配性好,而且对太阳电池的表面及体钝化效果最优。     

正向偏置电压修复钙钛矿太阳电池的研究

采用偏置电压调控钙钛矿太阳电池离子迁移,抑制钙钛矿离子在界面的堆积、填充太阳电池缺陷,恢复老化太阳电池的性能。在对老化太阳电池引入正向偏置电压修复手段后,太阳电池光电转换效率从老化后的17.8%恢复到21.5%;在100 h的最大功率点跟踪中引入偏置电压修复手段后,获得3.1%总能量增益。通过自主搭建的集成表征环境,原位实时测量偏压修复太阳电池前后太阳电池电学性能和光学特性的变化规律,建立偏压调控钙钛矿离子迁移的物理模型,探究偏置电压修复太阳电池的背后机理。结果表明,该修复策略可通过调控离子迁移,钝化缺陷、优化载流子提取和输运、进而修复太阳电池。     

基于恒负载下太阳电池自身温度对其发电性能影响的实验研究

基于分布式太阳发电储热供暖系统,针对多晶硅太阳电池自身温度对其发电性能的影响进行实验研究。在自然条件下对太阳电池加恒阻值的远红外发热纤维软板进行实验,测试其输出电压、输出电流及其对应的光伏电池表面光照强度、太阳电池自身温度,并对测试数据进行整理、分析,研究太阳电池自身温度对其发电性能的影响。结果表明:太阳电池表面光照强度一定时,随着太阳电池自身温度的升高,太阳电池输出电压、电流及输出功率明显减小,太阳电池的光电转换率呈线性下降趋势。     

CdS／CdTe－CdS／Cu_2S异质二重结薄膜太阳电池的设计与计算

根据半导体材料的性能参数，考虑光电压Ｖ和耗尽区宽度Ｗ的变化对光电流ＪＬ的影响，较严格地计算了ＣｄＳ／ＣｄＴｅ和ＣｄＳ／Ｃｕ２Ｓ两种异质结单晶薄膜太阳电池的光伏特性曲线。然后在的条件下，对由上述两种异质结构成的二重结太阳电池的ＣｄＴｅ、Ｃｕ２Ｓ厚度进行匹配，计算各种组合下二重结太阳电池的光伏特性曲线。理论证明最佳匹配厚度Ｈｍａｘ约为９．０６μｍ，最大短路电流、开路电压、转换效率分别为１４．２２ｍＡｃｍ－２、１．３Ｖ和１４、６８％。     

太阳电池内部电阻对其输出特性影响的仿真

通过对太阳电池的等效电路进行分析,建立了太阳电池的计算机仿真模型,定量地模拟了在一定光照下太阳电池内部的等效并联电阻及串联电阻对其伏安特性、开路电压、短路电流及填充因子的影响的程度。仿真结果表明：等效并联电阻产生的漏电流会影响太阳电池的反向特性和正向小偏压特性,且并联电阻影响其开路电压,但对短路电流基本没有影响；等效串联电阻会影响太阳电池的正向伏安特性和短路电流,而对开路电压没有影响；另外,并联电阻的减小和串联电阻的增大都会使太阳电池的填充因子和光电转换效率降低。仿真结果与实际测量的数据取得了相一致的结论。     

不同天气太阳电池板输出电压全日响应特性

开展武汉地区不同天气太阳电池板输出电压全日响应特性的实验观测,对水平0°以及正南方30°、60°这3个不同角度布置的太阳电池板输出电压特性开展连续测试,得到3个不同角度太阳电池板在4种天气下的全日响应曲线,提出5个表征太阳电池板日照利用效率的特征参数,分析特征参数的变化规律以及4种天气对这些特征参数的影响。研究发现,天晴或多云时太阳电池板输出电压全日幅值曲线近似为方波,阴雨时则为拱形波,晴天输出电压响应快,输出电压稳定。晴天时输出电压90%峰值持续时间是总持续时间的86%,多云时为84%,阴天时为68%,雨天时为64%,晴天及多云天气太阳电池板日照利用效率较高。     

迭层太阳电池中电流、电压及功率分配的理论分析

为了从理论上了解迭层太阳电池的工作特性,根据单结太阳电池直流模型提出了迭层电池的直流模型。并在模型基础上给出了描述迭层电池工作特性的方程组。在迭层电池模型和方程组的基础上,讨论了迭层电池开路状态和短路状态下电池内部电流,电压及功率分配。重点讨论了迭层电池对外做功情况下电流,电压功率在迭层电池中的分配。论证了迭层电池中,要求获得最大的功率输出。其子电池电流必须满足匹配关系。     

测量方式对太阳电池输出性能测试的影响

通过对二线与四线接法测试单晶硅太阳电池I-V曲线的实验结果对比,分析串联内阻对于太阳电池短路电流、开路电压、填充因子及最大输出功率测量结果的影响.结果发现串联内阻越大,太阳电池的短路电流、填充因子及最大输出功率测量结果越小,但对开路电压基本无影响.且太阳电池接收光强越大即输出电流越大时,串联内阻的影响也越大.二线法因串...     

弱光下晶体硅太阳电池的开路电压

讨论了弱光下影响晶体硅太阳电池开路电压的主要因素。要提高弱光下开路电压主要应提高太阳电池的并联电阻。     

一种计算空间电池阵输出的新方法

在求解太阳电池阵输出的方法中,有的方法能求出输出功率,但不能求出输出电流、输出电压;有的虽能求出输出电流、电压,但未考虑太阳辐射光强对它们的影响。本文提出一种新的方法,能求出太阳电池阵工作温度、输出电流和输出电压,并考虑了太阳辐射光强的影响。该方法包括一个I-V特征关系式和一个能量平衡模型。光强和太阳电池的温度是I-V特征关系式中的变量。能量平衡模型是在稳态、忽略太阳电池的热容条件下建立的。用该种方法分析了安装在太阳能飞机上的太阳能电池阵。     

Optimum matching of ohmic loads to the photovoltaic array

Optimum matching of loads to the photovoltaic (PV) generator is most desirable for more accurate sizing, higher system performance and maximum utilization of the costly solar array generator. The quality of load matching depends on the PV array characteristics, the load characteristics, and the insolation profile. A matching factor is defined as the ratio of the load energy to the array maximum energy over a one day period. Optimum matching is achieved by determining the optimal array parameters with respect to the load parameters. Optimization is done using direct-search techniques. Results show that the theoretical optimum matching factor for an ohmic load is 94.34%. For an electrolytic load the matching factor could reach 99.83%. A maximum power tracker can be eliminated if optimum matching is achieved.     

卫星太阳翼在轨输出功率预测模型

该文介绍一种卫星太阳翼在轨功率输出预测方法,由单体太阳电池根据固体物理理论推导出来直流理论分析模型获得其等效电路,通过对单体太阳电池串、并联后组成的太阳翼电气电路,获得太阳翼等效电路,并根据该等效电路推导出太阳翼的直流分析模型。将太阳翼的直流分析模型转化为由单片太阳电池片开路电压Voc、短路电流Isc、最大功率点电压Vmp、最大功率点电流Imp这4个参数决定的太阳翼工程应用方程。同时,通过地面试验获得单体太阳电池的电压和电流衰降系数,获取太阳翼实际在轨不同时刻的开路电压VAoc、短路电流IAsc、最大功率点电压VAmp、最大功率点电流IAmp,并通过计算获取太阳翼工作点电压、电流,得到太阳翼的在轨预测工作输出功率。通过将该文模型预测值与太阳翼实际在轨输出电流、电压遥测值进行比较,验证该预测模型的有效性。该预测模型可通过单体太阳电池的4个工程参数,获得整个太阳翼的直流分析模型,便于太阳翼设计阶段建模分析的工程化应用。     

MATCHING OF SEPARATELY EXCITED DC MOTORS TO PHOTOVOLTAIC GENERATORS FOR MAXIMUM POWER OUTPUT

This paper addresses the matching of separately excited dc motors to photovoltaic generators (PVG) for maximum power output. The dc motor is used to drive a centrifugal water pump. A PVG is a nonlinear device having insolation dependent I–V (current–voltage) characteristic, and hence a natural mismatch exists between the motor loads and the PVG. Therefore, considering the high initial cost of PVG, it is of vital importance to develop an appropriate matching process, to utilize PVG efficiently. In this article a procedure is developed to express the field current of the motor directly in terms of the maximum power point current and voltage of the PVG. It is shown that by adjusting the field current according to the developed relation, the motor is forced to follow the maximum power trajectory of the PVG, i.e. the input power of the motor is always equal to the maximum output power of the PVG at any available solar insolation. The effect of temperature on the I–V characteristic of the PVG is neglected at this stage. Finally a general expression is proposed relating the optimum field current directly to the available insolation level, which may be used as base for best matching.     

Optimum load matching in direct-coupled photovoltaic powersystems-application to resistive loads

The load matching factor is used as a measure for the quality of load matching to a photovoltaic (PV) array. An optimization approach is used to solve the load matching problem with the objective of maximizing the load matching factor, and consequently the PV output energy. This approach is then applied to resistive loads (with and without an internal EMF) connected to the array. Results show that optimum matching can be achieved by carefully selecting the array parameters with respect to the load parameters. The temperature of the array has little effect on the optimum matching factor. However, the optimum matching parameters are greatly affected by the array temperature. A maximum power tracker may not be achieved     

A novel on-line MPP search algorithm for PV arrays

A novel maximum power point (MPP) search algorithm for photovoltaic (PV) array power systems is introduced. The proposed algorithm determines the maximum power point of a PV array for any temperature and solar irradiation level using an online procedure. The method needs only the online values of the PV array output voltage and current, which can be obtained easily by using just current and voltage transducers. The algorithm requires neither the measurement of temperature and solar irradiation level nor a PV array model that is mostly used in look-up table based algorithms. Satisfactory results were obtained with the proposed algorithm in a laboratory prototype implementation scheme consisting of a PV array computer emulation model, a chopper controlled permanent magnet DC motor, and a DT2827 data acquisition board with the ATLAB software drivers for interfacing     

基于空间矢量PWM法的光伏水泵变频控制系统

介绍一种基于空间矢量PWM控制的光伏水泵变频控制系统。该空间矢量PWM算法具有对光伏阵列母线电压的动态补偿功能，保证在光伏阵列工作电压大范围变化条件下，变频驱动电机满足恒磁通调速控制。同时结合光伏水泵系统的工作特点，提出了一种简单实用的光伏阵列最大功率点跟踪控制方式，稳定可靠地实现了系统的最大功率点跟踪控制。     

CVT光伏泵水系统瞬态工作点特性分析

采用定电压跟踪器（CVT）的光伏水泵系统在不同地区已成功地投入实际应用。实地运行数据表明，CVT不能适应太阳电池阵列伏安特性的变化，使系统瞬态工作点偏离阵列输出最大功率点，导致系统功率损失。该文报道了2.5kWp，光伏水泵系统的基本构成和典型实地运行数据，并对系统瞬态工作点特性进行了分析讨论。     

A study of water electrolysis with photovoltaic solar energy conversion

The performance of the hydrogen production system consisting of the photovoltaic array and the water electrolysis unit is studied. The results of the calculation are compared with available experimental data and the performance of a hydrogen production plant by means of photovoltaic solar energy conversion is determined for two typical locations. A method for the estimation of the power matching conditions of the system solar array electrolysis unit is formulated to allow conclusions of general validity.