Analysis for Effects of Temperature Rise of PV Modules upon Driving Distance of Vehicle Integrated Photovoltaic Electric Vehicles

The development of vehicle integrated photovoltaics-powered electric vehicles (VIPV-EV) significantly reduces CO2 emissions from the transport sector to realize a decarbonized society. Although long-distance driving of VIPV-EV without electricity charging is expected in sunny regions, driving distance of VIPV-EV is affected by climate conditions such as solar irradiation and temperature rise of PV modules. In this paper, detailed analytical results for effects of climate conditions such as solar irradiation and temperature rise of PV modules upon driving distance of the VIPV-EV were presented by using test data for Toyota Prius and Nissan Van demonstration cars installed with high-efficiency InGaP/GaAs/InGaAs 3-junction solar cell modules with a module efficiency of more than 30%. The temperature rise of some PV modules studied in this study was shown to be expressed by some coefficients related to solar irradiation, wind speed and radiative cooling. The potential of VIPV-EV to be deployed in 10 major cities was also analyzed. Although sunshine cities such as Phoenix show the high reduction ratio of driving range with 17% due to temperature rise of VIPV modules, populous cities such as Tokyo show low reduction ratio of 9%. It was also shown in this paper that the difference between the driving distance of VIPV-EV driving in the morning and the afternoon is due to PV modules’ radiative cooling. In addition, the importance of heat dissipation of PV modules and the development of high-efficiency PV modules with better temperature coefficients was suggested in order to expand driving range of VIPV-EV. The effects of air-conditioner usage and partial shading in addition to the effects of temperature rise of VIPV modules were suggested as the other power losses of VIPV-EV.

Study on Image Recognition Algorithm for Residual Snow and Ice on Photovoltaic Modules

The accumulation of snow and ice on PV modules can have a detrimental impact on power generation,leading to reduced efficiency for prolonged periods.Thus,it becomes imperative to develop an intelligent system capable of accurately assessing the extent of snow and ice coverage on PV modules.To address this issue,the article proposes an innovative ice and snow recognition algorithm that effectively segments the ice and snow areas within the collected images.Furthermore,the algorithm incorporates an analysis of the morphological characteristics of ice and snow coverage on PV modules,allowing for the establishment of a residual ice and snow recognition process.This process utilizes both the external ellipse method and the pixel statistical method to refine the identification process.The effectiveness of the proposed algorithm is validated through extensive testing with isolated and continuous snow area pictures.The results demonstrate the algorithm’s accuracy and reliability in identifying and quantifying residual snow and ice on PV modules.In conclusion,this research presents a valuable method for accurately detecting and quantifying snow and ice coverage on PV modules.This breakthrough is of utmost significance for PV power plants,as it enables predictions of power generation efficiency and facilitates efficient PV maintenance during the challenging winter conditions characterized by snow and ice.By proactively managing snow and ice coverage,PV power plants can optimize energy production and minimize downtime,ensuring a sustainable and reliable renewable energy supply.

Maximizing Solar Potential Using the Differential Grey Wolf Algorithm for PV System Optimization

Maximum Power Point Tracking(MPPT)is crucial for maximizing the energy output of photovoltaic(PV)systems by continuously adjusting the operating point of the panels to track the point of maximum power production under changing environmental conditions.This work proposes the design of an MPPT system for solar PV installations using the Differential Grey Wolf Optimizer(DGWO).It dynamically adjusts the parameters of the MPPT controller,specifically the duty cycle of the SEPIC converter,to efficiently track the Maximum Power Point(MPP).The proposed system aims to enhance the energy harvesting capability of solar PV systems by optimizing their performance under varying solar irradiance,temperature and shading conditions.Simulation results demonstrate the effectiveness of the DGWO-based MPPT system in maximizing the power output of solar PV installations compared to conventional MPPT methods.This research contributes to the development of advanced MPPT techniques for improving the efficiency and reliability of solar energy systems.

Analysis of the Effect of Temperature and Relative Humidity on the Reliability of a Photovoltaic Module

Photovoltaic energy occupies a significant place in the renewable energy market, with photovoltaic (PV) modules playing a vital role in converting solar energy into electricity. However, their effectiveness is likely to be affected by variations in environmental conditions, including temperature and relative humidity. The study examines the impact of these major climatic factors on the reliability of PV modules, aiming to provide crucial information for optimizing and managing these systems under varying conditions. Inspired by Weibull’s law to model the lifespan of components, we proposed a mathematical model integrating a correction factor linked to temperature and relative humidity. Using this approach, simulations in Matlab Simulink reveal that increasing temperature and relative humidity have an adverse impact on the reliability and lifespan of PV modules, with a more pronounced impact on temperature. The results highlight the importance of considering these environmental parameters in the management and optimization of photovoltaic systems to ensure their long-term efficiency.

PV Capacity Evaluation Using ASTM E2848: Techniques for Accuracy and Reliability in Bifacial Systems

A variety of test methodologies are commonly used to assess if a photovoltaic system can perform in line with expectations generated by a computer simulation. One of the commonly used methodologies across the PV industry is an ASTM E2848. ASTM E2848-13, 2023 test method provides measurement and analysis procedures for determining the capacity of a specific photovoltaic system built in a particular place and in operation under natural sunlight. This test method is mainly used for acceptance testing of newly installed photovoltaic systems, reporting of DC or AC system performance, and monitoring of photovoltaic system performance. The purpose of the PV Capacity Test and modeled energy test is to verify that the integrated system formed from all components of the PV Project has a production capacity that achieves the Guaranteed Capacity and the Guaranteed modeled AEP under measured weather conditions that occur when each PV Capacity Test is conducted. In this paper, we will be discussing ASTM E2848 PV Capacity test plan purpose and scope, methodology, Selection of reporting conditions (RC), data requirements, calculation of results, reporting, challenges, acceptance criteria on pass/fail test results, Cure period, and Sole remedy for EPC contractors for bifacial irradiance.

基于PVsyst的单面与双面光伏组件最佳安装倾角对比

随着光伏发电技术不断进步,单面光伏组件与双面光伏组件的价差不断缩小。得益于发电量增益大,双面光伏组件在实际项目中受到愈来愈多的青睐。当光伏发电项目采用单面或双面光伏组件时,光伏组件的最佳安装倾角成为一个重要的考虑因素。选取了3个太阳能资源等级地区,利用PVsyst对在这3个地区建设的光伏电站分别采用单面和双面光伏组件时的安装倾角与光伏电站首年发电量及光伏组件正面接收的太阳辐照量之间的关系进行了仿真模拟。得到以下结论:1)以光伏电站首年发电量最大为衡量标准时,双面光伏组件的最佳安装倾角大于或等于有阴影遮挡的单面光伏组件的最佳安装倾角,但小于无阴影遮挡的单面光伏组件的最佳安装倾角。2)就单面光伏组件而言,无阴影遮挡条件下增加光伏组件安装倾角带来的发电量增益高于有阴影遮挡安装条件时。3)在无阴影遮挡情况下,在一定范围内增大单面光伏组件的安装倾角可以相应提升其发电量;相对于双面光伏组件,无阴影遮挡的单面光伏组件通过适当提高其安装倾角所获得的发电量增益较小,且增大安装倾角,光伏阵列之间的间距也需要相应增加,这会增大用地量,从而增加项目总成本。因此,在实际项目中,尽可能采用双面光伏组件是一个较为理想的选择。

基于PVLIB的光伏组件串联数量计算条件及方法分析

为得到更为高效且合理的光伏组件串联数量的计算条件和计算方法,选取位于不同纬度、不同气候类型的119个拟定项目地点,基于PVLIB和NASA的气象数据获取119个拟定项目地点的20年逐小时气象数据,对采用不同计算条件时得到的光伏组件开路电压及其对应的光伏组件串联数量进行了分析。分析结果显示:基于200 W/m^(2)太阳辐照度及历史最低气温计算得到的光伏组件串联数量与基于多年逐时气象数据计算得到的光伏组件串联数量结果相近,且计算方法较为简便,不需要长序列逐时气象数据,可用于光伏电站设计中光伏组件串联数的计算条件。

半透明光伏组件在BIPV中的优化应用研究

因半透明光伏组件能够同时实现光伏发电和保持透光性,其在现代绿色建筑中的应用潜力被广泛认可。采用数值模拟方法,基于半透明光伏组件在实际光伏建筑一体化(BIPV)项目中的适用性研究,进一步分析了其在满足建筑用能和采光质量条件下的优化应用。研究结果表明:优化设计对改善建筑室内光环境和提升节能降碳效益具有积极影响,并确认了合理优化采光分布的重要性。研究结果为半透明光伏组件在BIPV中的应用提供了实用的设计策略和实践参考。

MPPT Control System for PV Generation System with Mismatched Modules

Nowadays, in a household PV （photovoltaic） generation system, it is generally connecting PV modules in series and then output to the power-conditioner. However, when PV modules are mismatched, it will lead to a wrong MPPT （maximum power point tracking） to all modules and a power decreasing of the whole system. Aiming at this problem, this paper presents the idea which improves the MPPT without changing the conventional power-conditioner, by adding a Buck type DC-DC （direct current） converter behind each module. Simulations of PSIM （power simulation） and experiments are taken to prove this theory. The result shows that, by this idea, the generated power of the conventional PV generation system can be greatly increased under the condition of mismatch.

一种新型PV AC Module的研究

为了解决传统的两级式光伏交流模块PV AC module存在的结构复杂、成本高、效率低等问题,提出了一种新型PV AC module。该AC module的前级为传统的Boost变换器,完成光伏组件的最大功率点跟踪和光伏接口电压的泵升;后级采用高增益集成式逆变器,实现直流母线电压的泵升和并网发电功能。分析了PV AC module的系统结构,工作原理及控制策略,并通过一套250 W/40 kHz的样机仿真模型,验证了方案的可行性与理论分析的正确性。研究结果表明:该新型PV AC module具有结构简洁、控制简单、成本低、效率高等优点。

积尘形态及密度对太阳能PV/T系统的性能影响研究

在室外搭建太阳能光伏/热(PV/T)系统实验测试平台,研究积尘形态及密度对系统性能的影响。研究结果表明:积尘形态主要影响太阳能PV/T系统的光热效率,积尘密度主要影响系统的光电效率。与松散积尘相比,粘结积尘对系统光热效率及综合效率的影响更大。当松散积尘密度从0变化至33.79 g/m^(2)时,系统的光热效率下降率仅为2.32%,而系统的光电效率下降率高达48.65%。在该文实验中,随着积尘密度的增大,太阳电池的工作温度依次为53.99、52.92、50.73和55.58℃,呈先降后增的变化趋势。故少量积尘不会使太阳能PV/T系统中太阳电池的工作温度升高而影响其正常工作。

Photovoltaic Cells and Modules towards Terawatt Era

Progresses in photovoltaic technologies over the past years are evident from the lower costs, the rising efficiency, to the great improvements in system reliability and yield. Cumulative installed power yearly growths were on an average more than 40% in the period from 2007 to 2016 and in 2016, the global cumulative photovoltaic power installed has reached 320 GWp. The level 0.5 TWp could be reached before 2020. The production processes in the solar industry still have great potential for optimization both wafer based and thin film technologies. Trends following from the present technology levels are discussed, also taking into account other parts of photovoltaic systems that influence the cost of electrical energy produced. Present developments in the three generations of photovoltaic modules are discussed along with the criteria for the selection of appropriate photovoltaic module manufacturing technologies. The wafer based crystalline silicon(csilicon) technologies have the role of workhorse of present photovoltaic power generation, representing more than 90% of total module production. Further technology improvements have to be implemented without significantly increasing costs per unit, despite the necessarily more complex manufacturing processes involved. The tandem of c-silicon and thin film cells is very promising. Durability may be a limiting factor of this technology due to the dependence of the produced electricity cost on the module service time.

Resiliency oriented control of a smart microgrid with photovoltaic modules

The resiliency of a standalone microgrid is of considerable issue because the available regulation measures and capabilities are limited.Given this background,this paper presented a new mathematical model for a detailed photovoltaic(PV)module and the application of new control techniques for efficient energy extraction.The PV module employs a single-stage conversion method to integrate it with the utility grid.For extraction the maximum power from PV and integrate it to power grid,a three-phase voltage source converter is used.For obtaining the maximum power at a particular irradiance a maximum power point tracking(MPPT)scheme is used.The fuzzy logic control and adaptive network-based fuzzy inference system are proposed for direct current(DC)link voltage control.The proposed model and control scheme are validated through a comparison with the standard power-voltage and current-voltage charts for a PV module.Simulation results demonstrate that the system stability can be maintained with the power grid and in the island mode,in contrast with the MPPT.

基于PVsyst的光伏系统研究

基于PVsyst软件,以吐鲁番地区某民居为模拟对象,对当地的气象数据进行分析,并构建了一套安装在屋顶的光伏并网发电系统。对光伏并网系统的安装倾角进行优化,并对光伏组件进行选型,对系统损失进行分析。最后根据模拟结果,对影响系统发电效率的因素进行分析并提出了一些优化方案,以及得出吐鲁番地区19.1 kW的光伏并网系统全年发电量为27.9 MW·h,系统效率为80.9%,能量回收期为2.98年,每年可减少32790 kg的CO_(2)排放量,具有一定的环境效益;若按新疆光伏上网电价0.262元(/kW·h)进行计算,每年还可带来7309.8元的收入。该研究对实际光伏并网系统的设计施工具有一定的参考意义。

Effect of Dust and Shadow on Performance of Solar Photovoltaic Modules: Experimental Analysis

This study presents an experimental performance of a solar photovoltaic module under clean,dust,and shadow conditions.It is found that there is a significant decrease in electrical power produced(40%in the case of dust panels and 80%in the case of shadow panels)and a decrease in efficiency of around 6%in the case with dust and 9%in the case with the shadow,as compared to the clean panel.From the results,it is clear that there is a substantial effect of a partial shadow than dust on the performance of the solar panel.This is due to the more obstruction of the sunlight by the shadowed area compared to the dust.The dust being finer particles for the given local experimental condition did not influence the panel than the shadow.The main outcome of this study is that the shadowing effect may cause more harm to the PV module than dust for the given experimental conditions.However,Further long-term studies on the effect of dust and shadow are needed to understand the effect on performance degradation and module life.

Investigation of the Performance of CIS Photovoltaic Modules under Different Environmental Conditions

This work investigates the effects of temperature and radiation intensity on the parameters of a copper indium diselenide (CIS) photovoltaic module. The module performance parameters are determined from calculated module parameters. An outdoor experimental setup is installed to carryout a series of I-V curve measurements under different irradiance and temperature conditions for the module. A numerical model which considers the effect of series and shunt resistances is developed to evaluate the different parameters of PV modules. Orthogonal distance regression (ODR) algorithm is adapted for fitting I-V measurements and extracting module parameters from I-V measurements. The values of module parameters, series resistance Rs, shunt resistance Rsh, diode ideality factor n and reverse saturation current Io determined from I-V measurements at different irradiation intensity and temperature range are in good agreement with the corresponding parameters obtained from the developed numerical model. The module parameters extracted from I-V measurements are employed to calculate the module performance parameters, i.e. open circuit voltage Voc, fill factor FF and module efficiency η at different irradiation intensity and temperature range. Present results indicate that the largest drop in open circuit voltage Voc due to about 20℃ increase in temperature is approximately 8.8% which is not compensated for by the relatively small increase in short circuit current, (2.9% in Isc), resulting in a reduction in maximum power of about 6.3%. Results let us conclude that the shunt resistance RSh increases with radiation at low radiation values (2). As radiation increases at high radiation values (> 400 W/m2), RSh begins to decease sharply and dramatically. Also, as the light intensity incident on the solar module increases, the series resistance and the output voltage decrease. When the irradiance intensity increases, the series resistance decreases but with a very low rate at the two studied temperatures ranges. The low rate decrease of Rs is found to have little effect on module performance in comparison with the significant change of other module parameters. The ideality factor n and saturation current Io decrease first sharply in the low range of radiation intensity (2) and this decrease becomes smaller for irradiance values greater than 400 W/m2. The previous observations and conclusions regarding the module parameters RSh, RS, n and Io obtained at 20℃ observed again at 40℃ but there is a great difference between the peak values of RSh at both temperature levels. Present results also show that module efficiency decreases with increasing irradiance intensity due to the combined effect of both Voc and FF.

基于PVsyst的“跟踪支架+双面组件”光伏发电系统的发电量评估方法研究

以内蒙古自治区鄂尔多斯地区某个拟转移所有权的新建光伏领跑者项目为例,对双面光伏组件分别与平单轴和斜单轴跟踪支架结合时光伏发电系统第0年的理论上网电量进行分析,进而得到该项目寿命期内各年的理论上网电量、等效满负荷利用小时数,以及25年的理论年平均上网电量和年平均等效满负荷利用小时数。结果显示:计算得到的项目年平均等效满负荷利用小时数低于可研设计值,高于根据实际上网电量测算得到的值。以期可为项目收购决策和经济性分析提供科学参考及依据。

Comparison between the Energy Required for Production of PV Module and the Output Energy Througout the Product Life Time

Electrical energy consumption is growing and is necessary to improve the technologies related to energy production. We have carried out a pilot study about environmental impacts during the manufacturing process of PV （photovoltaic） modules and compared between the energy requirement for the production of PV cells and modules and generation throughout the life time of the finished good that is PV module. It was taken into account the generation of environmental aspects and impacts in the manufacture of monocrystalline silicon PV modules （consisting of three components： silicon cell, fiat tempered glass and aluminum frame）, and an analysis of a grid-connected PV system using an energetic alternative in residences was considered. Results show that, this kind of renewable energy is really clean and can be considered as a way to change the energy technology.

光伏幕墙辅助双源热泵系统在不同地区的多目标优化配置

为克服单一可再生能源应用的局限性,提出一种光伏幕墙辅助双源热泵系统。利用TRNSYS建立仿真模型,以系统能耗和生命周期成本为目标函数,采用非支配排序遗传算法(NSGA-Ⅱ),对不同地区系统配置规模进行多目标优化设计,并利用加权和法确定均衡解。结果表明:哈尔滨、长春、沈阳3个地区优化后的系统运行能耗比优化前分别增加5.9%、5.0%和3.9%,生命周期成本降低13.6%、17.1%和12.9%;与单目标优化相比,多目标优化在兼顾性能的前提下能明显降低生命周期成本,具有明显的优势。

基于改进EfficientNet的红外图像光伏组件故障识别研究

光伏组件的故障会影响光伏阵列的输出性能,从而降低电站的发电效率,严重时甚至会危害电站的安全运行。传统的方法无法满足目前光伏组件故障检测快速性和正确率需求。因此,本文提出了一种基于改进EfficientNet的光伏组件故障识别方法。首先,利用采集到的光伏组件红外图像建立故障数据集,并利用图像分割和数据增强对数据集进行预处理;其次,基于EfficientNet网络构建故障识别模型,同时在模型中引入双通道注意力模块(CBAM),该模块能够抑制不必要特征的识别,增强模型对空间特征信息的提取能力,进而提高模型的识别准确率;最后,通过对比仿真实验证明模型的有效性和先进性。实验结果表明,该模型的故障识别准确率达到了90.83%,相较于原始的EfficientNet模型提高了2.83%,且模型大小仅为20.3 M,具有良好的实用性,能够满足光伏电站实际应用的需求。