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Analysis of Solar PV cell Performance with Changing Irradiance and Temperature
Pradhan Arjyadhara,Ali S.M,Jena Chitralekha
International Journal of Engineering and Computer Science , 2013,
Abstract: Solar energy is most readily available source of energy. It is Non polluting and maintenance free. To make best use of the solar PV systems the output is maximized either by mechanically tracking the sun and orienting the panel in such a direction so as to receive the maximum solar irradiance or by electrically tracking the maximum power point under changing condition of insolation and temperature. The overall performance of solar cell varies with varying Irradiance and Temperature .With the change in the time of the day the power received from the Sun by the PV panel changes. Not only this both irradiance and temperature affect solar cell efficiency as well as corresponding Fill factor also changes. This paper gives an idea about how the solar cell performance changes with the change in above mentioned factors in reality and the result is shown by conducting a number of experiments.
Availability, Performance and Reliability Evaluation for PV Distributed Generation  [PDF]
Abdulrahman K. Al-Sefri, Abdullah M. Al-Shaalan
World Journal of Engineering and Technology (WJET) , 2019, DOI: 10.4236/wjet.2019.73032
Abstract: Nowadays, renewable energy resources play an important role in replacing conventional energy resources such as fossil fuel by integrating solar, wind and geothermal energy. Photovoltaic energy is one？of？the very promising renewable energy resources which grew rapidly in the past few years, it can be used to produce electric energy through photovoltaic process. The primary objective of the research proposed in this paper is to facilitate the increasing penetration levels of PV systems in the electric distribution networks. In this work, the PV module electrical model is presented based on the mathematical equations and was implemented on MATLAB to simulate the non-linear characteristics I-V and P-V curves with variable input parameters which are irradiance and temperature based on Riyadh region. In addition, the reliability evaluation of distribution networks, including distributed generators of solar photovoltaic (PV) with varying output power capacity is presented also. The Monte Carlo simulation algorithm is applied to test the distribution network which is RBTS Bus 2 and the same has been conducted on the original case of distribution network substation 7029 which is located at KSA Riyadh. The two distribution networks have been modified to include the PV’s distributed generators. The distributed generators contribute to supply a part of the load during normal mode and supply the entire load during component failure or failure of grid operation supply. The PV stochastic models have been used to simulate the randomness of these resources. Moreover, the study shows that the implementation and integration of renewable resources as distributed generations have improved the reliability of the distribution networks.
Options for Control of Reactive Power by Distributed Photovoltaic Generators  [PDF]
Petr Sulc,Konstantin Turitsyn,Scott Backhaus,Michael Chertkov
Physics , 2010, DOI: 10.1109/JPROC.2011.2116750
Abstract: High penetration levels of distributed photovoltaic(PV) generation on an electrical distribution circuit present several challenges and opportunities for distribution utilities. Rapidly varying irradiance conditions may cause voltage sags and swells that cannot be compensated by slowly responding utility equipment resulting in a degradation of power quality. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We discuss and compare via simulation various design options for control systems to manage the reactive power generated by these inverters. An important design decision that weighs on the speed and quality of communication required is whether the control should be centralized or distributed (i.e. local). In general, we find that local control schemes are capable for maintaining voltage within acceptable bounds. We consider the benefits of choosing different local variables on which to control and how the control system can be continuously tuned between robust voltage control, suitable for daytime operation when circuit conditions can change rapidly, and loss minimization better suited for nighttime operation.
Impact of PV Distributed Generation on Loop Distribution Network  [PDF]
Mohammad A. Alrumaih, Abdullah M. Al-Shaalan
Journal of Power and Energy Engineering (JPEE) , 2019, DOI: 10.4236/jpee.2019.78002
Abstract: The rapid spreading of the Photovoltaic (PV) Systems as Distributed Generation (DG) in medium and low voltage networks created many effects and changes on the existing power system networks. In this work, two methods have been used and applied to determine the optimal allocation and sizing of the PV to be installed as DGs (ranging from 250 kW up to 3 MW). The first one is to determine the location according to the maximal power losses reduction over the feeder. The second one is by using the Harmony Search Algorithm which is claimed to be a powerful technique for optimal allocation of PV systems. The results of the two techniques were compared and found to be nearly closed. Furthermore, investigation on the effects on the feeder in terms of voltage levels, power factor readings, and short circuit current levels has been done. All calculations and simulations are conducted by using the MATLAB Simulation Program. Some field calculations and observations have been expended in order to substantiate the research findings and validation.
Efficient Maximum Power Point Tracking Algorithm for PV Application under Rapid Changing Weather Condition  [PDF]
Khaled M. Bataineh,Amr Hamzeh
ISRN Renewable Energy , 2014, DOI: 10.1155/2014/673840
Abstract: This study presents a novel search algorithm of maximum power point tracking for photovoltaic power generation systems. The I-V characteristics and the P-V power output under specific irradiation and temperature conditions are simulated. The performance of the algorithm under fully shaded and sudden partially shaded conditions as well as variable insulations levels is investigated. The developed algorithm performs a wide-range search in order to detect rapidly changing weather conditions, and keeps the simulated stand-alone or grid-connected systems continuously operating close to the maximum power point. The performance of the developed algorithm, under extremely changing environmental conditions, is found to be superior compared to that of other conventional algorithms. The results of this study show that, under uniform radiations conditions, the developed algorithm takes only half of the time required by the Perturbation and Observe algorithms to reach maximum power point MMP. Furthermore, when PV is subjected to sudden partial shading conditions, the algorithm rapidly detects these changes and reaches the new MMP in less than a second. 1. Introduction It is now widely accepted that the nonrenewable sources in the world are finite and it is only a matter of time before reserves will essentially be consumed [1, 2]. It has been proven that the use of nonrenewable energy sources has severe effect on the environment. Due to environmental awareness and technological advancement, high oil price, and government support, the renewable electricity generation capacity has reached an estimated 240 gigawatts (GW) worldwide in 2007 while it was 160？GW in 2004 [3]. The solar photovoltaic (PV) power system is attractive renewable energy source due to its availability and economic feasibility [4, 5]. Stand-alone PV systems are found suitable for powering remote areas [4]. The power produced by a PV module depends on the operating temperature, the amount of falling solar irradiance over the PV Cells array, and the load connected [5, 6]. The power output of PV cells depends on the nonlinear current voltage (I-V) characteristics relationship. Because of this nonlinear relationship between the current and the voltage of the PV cell, there is a unique maximum power point at particular weather conditions, and this maximum power point keeps changing with the irradiance levels and ambient temperature. Therefore, a maximum power point tracking (MPPT) algorithm is commonly used, to obtain the maximum possible power under varying weather conditions and loads. Because of the
Physical Effects of Distributed PV Generation on California's Distribution System  [PDF]
Michael A. Cohen,Duncan S. Callaway
Physics , 2015,
Abstract: Deployment of high-penetration photovoltaic (PV) power is expected to have a range of effects -- both positive and negative -- on the distribution grid. The magnitude of these effects may vary greatly depending upon feeder topology, climate, PV penetration level, and other factors. In this paper we present a simulation study of eight representative distribution feeders in three California climates at PV penetration levels up to 100\%, supported by a unique database of distributed PV generation data that enables us to capture the impact of PV variability on feeder voltage and voltage regulating equipment. When comparing the influence of feeder location (i.e. climate) versus feeder type on outcomes, we find that location more strongly influences the incidence of reverse power flow, reductions in peak loading and the presence of voltage excursions. On the other hand, we find that feeder characteristics more strongly influence the magnitude of loss reduction and changes in voltage regulator operations. We find that secondary distribution transformer aging is negligibly affected in almost all scenarios.
Safety Impact of Large-Scale Distributed PV Power Access to Power Grids  [PDF]
Hualing Han,Ning Chen,Linan Qu,Tao Shi
International Journal of Computer and Electrical Engineering , 2013, DOI: 10.7763/ijcee.2013.v5.716
Abstract: Photovoltaic (PV) power generation is the fastest growing part of distributed generation technologies. Large-scale PV power connected to the grid is bound to the safe operation of the grid to bring new problems and challenges in China. Based on PSASP, combined with large-scale PV power access to the actual grid, this article establish PV model, do research on the characteristics of large-scale PV power stations and network system. In this article, the characteristics of PV grid-connected systems, stability and other issues accessing to large-scale PV system are discussed.
Performance of CdTe Solar Cells under Diffuse Solar Irradiance
M. Chegaar,A. Guechi
Journal of Engineering and Applied Sciences , 2012,
Abstract: This study investigates how CdTe thin film solar cells perform under varying diffuse solar spectrum due to the changes of environmental parameters. These parameters are, generally, the air mass, the atmospheric water vapour content, the turbidity and the albedo. The solar irradiance striking the solar cell is simulated using the spectral irradiance model SMARTS2 (Simple Model of the Atmospheric Radiative Transfer of Sunshine) for clear skies. The results show the short circuit current increases with increasing turbidity and albedo and it decreases with increasing air mass and atmospheric water vapour content but with different proportions. The performance of the cells is notably reduced, both in terms of efficiency and open circuit voltage, with increasing air mass but the cell performs better with increasing water vapour content, albedo and turbidity.
Antioxidative responses and expression of insecticidal proteins in Bt cotton under high irradiance  [PDF]
Parimala P.,Muthuchelian K.
Journal of Stress Physiology & Biochemistry , 2011,
Abstract: Effect of high irradiance (HI) on the activity of antioxidant enzymes, rate of lipid peroxidation and hydrogen peroxide accumulation were investigated in non Bt and Bt cotton. The accumulation of malondialdehyde (MDA) and H2O2 was higher in Bt cotton. Sustained cultivation of Bt cotton requires stable transgene expression under HI stress. In the present study, Bt toxin proteins (Cry1Ac and Cry2Ab), which are essential for the control of lepidopteron pests, were found to be reduced in Bt cotton under HI stress.
Experimental Study of Environmental Impact on the Efficiency of a House-Hold PV Panel  [PDF]
Yassir Idris Abdalla Osman, Jinping Li, Xiaofei Zhen
Smart Grid and Renewable Energy (SGRE) , 2018, DOI: 10.4236/sgre.2018.97008
Abstract: House-hold PV panels are widely used; however, their performance is significantly degraded under real operating conditions. Environmental factors such as ambient temperature, wind speed, and solar irradiance has a major impact on the house-hold PV panel efficiency. In this paper an experimental study was conducted during the winter period in a single building in Minqin county, Gansu province, China. The experimental measurements were used to quantify the house-hold PV panel performance and operating characteristics. Based on the experimental results the house-hold PV panel performance is basically affected by the PV surface temperature, therefore, multilevel of energy is detected. Approximately 3% efficiency variation is detected due to the impact of the environmental factors.
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