Durability of Materials in a Stress-Response Framework: Acrylic Materials for Photovoltaic Systems

2012 ◽  
Vol 1391 ◽  
Author(s):  
Myles P. Murray ◽  
Laura S. Bruckman ◽  
Roger H. French

ABSTRACTIn the development of novel materials for enhanced photovoltaic (PV) performance, it is critical to have quantitative knowledge of the initial performance, as well as the performance of these materials over the required 25-year lifetime of the PV system. Lifetime and degradation science (L&DS) allows for the development of new metrology and metrics, coupled to degradation mechanisms and rates. Induced absorbance to dose (IAD), a new metric being developed for solar radiation durability studies of solar and environmentally exposed photovoltaic materials, is defined as the rate of photodarkening or photobleaching of a material as a function of total absorbed solar radiation dose. In a reliability engineering framework, these quantitative degradation rates can be determined at various solar irradiances making possible real time and accelerated testing. The potential to predict power losses in a photovoltaic system over time caused by the accumulation of this kind of degradation can be calculated for real time applications or extrapolated for accelerated exposure conditions. Three formulations of poly (methyl methacrylate) (PMMA) used for mirror augmented PV systems were analyzed for the changes in IAD after accelerated testing.

2018 ◽  
Vol 218 ◽  
pp. 02004
Author(s):  
Iskandar Handoko Rusiana ◽  
Zainal Yuda Bakti ◽  
Susanto Sambasri

This study investigates the shading on PV systems. Shading has considerable influence on the solar cells characteristics, temperature and radiation on site need to be considered as the basis for designing PV systems. Modeling conducted on a 1 kWp PV system at a latitude of 6°53ˈ2.69̎S and a longitude of 107°32ˈ28.69̎, to find the magnitude of solar radiation, surface temperature, and tilt angle, and partial shadow simulation using PVsyst software. Testing result shows the characteristic PV 1 kWp is obtained with the angle of solar cell shade at 18˚, and azimuth 0˚, the shading per year generates 4.71 kWh/m2in a solar active area at 6.9m2, the power losses of 20.8% of its nominal power.


Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3152 ◽  
Author(s):  
Huadian Xu ◽  
Jianhui Su ◽  
Ning Liu ◽  
Yong Shi

Conventional photovoltaic (PV) systems interfaced by grid-connected inverters fail to support the grid and participate in frequency regulation. Furthermore, reduced system inertia as a result of the integration of conventional PV systems may lead to an increased frequency deviation of the grid for contingencies. In this paper, a grid-supporting PV system, which can provide inertia and participate in frequency regulation through virtual synchronous generator (VSG) technology and an energy storage unit, is proposed. The function of supporting the grid is implemented in a practical PV system through using the presented control scheme and topology. Compared with the conventional PV system, the grid-supporting PV system, behaving as an inertial voltage source like synchronous generators, has the capability of participating in frequency regulation and providing inertia. Moreover, the proposed PV system can mitigate autonomously the power imbalance between generation and consumption, filter the PV power, and operate without the phase-locked loop after initial synchronization. Performance analysis is conducted and the stability constraint is theoretically formulated. The novel PV system is validated on a modified CIGRE benchmark under different cases, being compared with the conventional PV system. The verifications demonstrate the grid support functions of the proposed PV system.


Author(s):  
Mohammed Bouzidi ◽  
Abdelkader Harrouz ◽  
Tadj Mohammed ◽  
Smail Mansouri

<p>The inverter is the principal part of the photovoltaic (PV) systems that assures the direct current/alternating current (DC/AC) conversion (PV array is connected directly to an inverter that converts the DC energy produced by the PV array into AC energy that is directly connected to the electric utility). In this paper, we present a simple method for detecting faults that occurred during the operation of the inverter. These types of faults or faults affect the efficiency and cost-effectiveness of the photovoltaic system, especially the inverter, which is the main component responsible for the conversion. Hence, we have shown first the faults obtained in the case of the short circuit. Second, the open circuit failure is studied. The results demonstrate the efficacy of the proposed method. Good monitoring and detection of faults in the inverter can increase the system's reliability and decrease the undesirable faults that appeared in the PV system. The system behavior is tested under variable parameters and conditions using MATLAB/Simulink.</p>


2020 ◽  
Vol 12 (22) ◽  
pp. 9750
Author(s):  
Ali Hasan Shah ◽  
Ahmed Hassan ◽  
Mohammad Shakeel Laghari ◽  
Abdulrahman Alraeesi

Dust accumulation on the photovoltaic (PV) surface decreases the solar radiation penetration to the PV cells and, eventually, the power production from the PV system. To prevent dust-based power losses, PV systems require frequent cleaning, the frequency of which depends on the geographical location, PV integration scheme, and scale of the PV power plant. This study aims to measure the drop-in radiation intensity, as well as power output, due to dust and to determine the optimal time interval for PV cleaning in the United Arab Emirates (UAE) climate. In this research, a dusting study experiment was carried out at the Renewable Energy Laboratory, Falaj Hazza Campus, UAE University, Al Ain, UAE, for 3.5 months, from 22 April 2018 to 7 August 2018. To measure the pure radiation losses caused by the dust, four transparent glasses were used to mimic the top glass cover of the PV modules. The dusting induced power losses were measured for four selected PV cleaning frequencies (10 days, 20 days, 1 month, and 3 months). This study revealed that up to 13% of power losses occurred in PV panels that remained dusty for 3 months, compared to panels that were cleaned daily. PV cleaning after 15 days brought the losses down to 4%, which was found the most feasible time for PV cleaning in this study, considering a reasonable balance between the cleaning cost and energy wasted due to soiling.


2018 ◽  
Vol 225 ◽  
pp. 04004
Author(s):  
Tan Dei Han ◽  
Mohamad Rosman M. Razif ◽  
Shaharin A. Sulaiman

Solar photovoltaic (PV) systems has the potential of supplying infinite electricity from renewable energy to rural areas around Malaysia. Various preterm failures happening frequently on the system lead to its drop in efficiency and breakdown. Lack of studies on the system in Malaysia hinders the development in terms of operation and maintenance. There is no proper documentation relevant to the premature failure of the system in Malaysia. The main objective of this project is to study the nature of premature failure of stand-alone solar photovoltaic system in Malaysia in order to improve the operation and maintenance of the system. The present study would provide reference for proper planning on operation and maintenance of the PV system. The study was conducted base on expert’s input and extensive literature survey. FMEA method and ISM approach are applied to analyze the data collected. Poor cooling system have the highest risk priority number. Poor workmanship is the least depending factor for premature failure to happen thus requires most attention. Highest driving force of premature failure is poor monitoring and maintenance. More focus should be given to these premature failure during the planning for operation and maintenance due to its severity and impact.


2020 ◽  
Vol 12 (6) ◽  
pp. 2233
Author(s):  
Tamer Khatib ◽  
Dhiaa Halboot Muhsen

A standalone photovoltaic system mainly consists of photovoltaic panels and battery bank. The use of such systems is restricted mainly due to their high initial costs. This problem is alleviated by optimal sizing as it results in reliable and cost-effective systems. However, optimal sizing is a complex task. Artificial intelligence (AI) has been shown to be effective in PV system sizing. This paper presents an AI-based standalone PV system sizing method. Differential evolution multi-objective optimization is used to find the optimal balance between system’s reliability and cost. Two objective functions are minimized, the loss of load probability and the life cycle cost. A numerical algorithm is used as a benchmark for the proposed method’s speed and accuracy. Results indicate that the AI algorithm can be successfully used in standalone PV systems sizing. The proposed method was roughly 27 times faster than the numerical method. Due to AI algorithm’s random nature, the proposed method resulted in the exact optimal solution in 6 out of 12 runs. Near-optimal solutions were found in the other six runs. Nevertheless, the nearly optimal solutions did not introduce major departure from optimal system performance, indicating that the results of the proposed method are practically optimal at worst.


Author(s):  
T. NARASIMHA PRASAD ◽  
V. LAKSHMI DEVI

Solar energy has become a very potential new energy; Connected directly with grid-connected photovoltaic (PV) systems does not require bulk and lossy battery. Distributed generation and on-site supply of PV system reduces losses of transmission and distribution, and mitigates environment pollution. This paper establishes a Dynamic model of grid-connected PV system by Matlab/Simulink with d-and q-axis as coordinates which is synchronously rotating with the grid voltage to reflect the characteristics of the system accurately. Based on the accurate modeling system, optimum control and fault analysis are studied. The simulation and analysis verify the effectiveness of the proposed algorithm, and demonstrate that the proposed control system has good static performance.


Author(s):  
Syafaruddin Syafaruddin

It is crucial to improve the photovoltaic (PV) system efficiency and to develop the reliability of PV generation control systems. One of the approaches to increase the efficiency of PV power generation system is to operate the PV systems optimally at the maximum power point. However, the PV system can be optimally operated only at a specific output voltage; otherwise the output power fluctuates under intermittent weather conditions. In addition, it is very difficult to test the performance of PV systems controller under the same weather condition during the development process where the field testing is costly and time consuming. For these reasons, the presentation is about the state of the art techniques to track the maximum available output power of photovoltaic systems called maximum power point tracking (MPPT) control systems. This topic could be also one of the most challenges in photovoltaic systems application that has been receiving much more attention worldwide. The talks will cover the application of intelligent techniques by means the artificial neural network (ANN) and fuzzy logic controller scheme using polar information to develop a novel real-time simulation technique for MPPT control by using dSPACE real-time interface system. In this case, the three-layer feed-forward ANN is trained once for different scenarios to determine the global MPP voltage and power and the fuzzy logic with polar information controller takes the global maximum power point (MPP) voltage as a reference voltage to generate the required control signal for the power converter. This type of fuzzy logic rules is implemented for the first time in MPPT control application. The proposed method has been tested using different solar cell technologies such as monocrystalline silicon, thin-film cadmium telluride and triple junction amorphous silicon solar cells. The verification of availability and stability of the proposed system through the real-time simulator shows that the proposed system can respond accurately for different scenarios and different solar cell technologies. In other cases, one of the main causes of reducing energy yield of photovoltaic systems is the partially shaded condition. Although the conventional MPPT control algorithms operate well in a uniform solar irradiance, they do not operate well in non-uniform solar irradiance conditions. The non-uniform conditions cause multiple local maximum power points on the power-voltage curve. The conventional MPPT methods cannot distinguish between the global and local peaks. Since the global power point may change within a large voltage window and also its position depends on shading patterns, it is very difficult to recognize the global operating point under partially shaded conditions. From these reasons, the presentation will address the effectiveness of the proposed MPPT method to solve the partially shaded conditions under the experimental real-time simulation technique based dSPACE real-time interface system for different size of PV arrays, such as 3x3(0.5kW) and 20x3(3.3kW) and different interconnected PV arrays, for instance series-parallel (SP), bridge link (BL) and total cross tied (TCT) configurations.


Author(s):  
Carlos Andrés Ramos-Paja ◽  
Daniel Gonzalez-Motoya ◽  
Juan Pablo Villegas-Seballos ◽  
Sergio Ignacio Serna-Garces ◽  
Roberto Giral

The wide range of step-up and step-down input-output voltage characteristic of the Cuk converter makes it a good candidate to interface photovoltaic arrays in both classical and distributed maximum power point tracking systems. Because its two inductor structure, Cuk converters have continuous input and output currents, which reduce the additional filtering elements usually required for interfacing dc/dc converter topologies. However, PV systems based on Cuk converters usually do not provide formal proofs of global stability under realistic conditions, which makes impossible to ensure a safe operation of the PV installation. Therefore, this paper proposes a high performance sliding-mode controller for PV systems based on Cuk converters, which regulates the PV voltage in agreement with the commands imposed by a MPPT algorithm, rejecting both load and environmental perturbations, and ensuring global stability for real operation conditions. Finally, the performance of the regulated PV system is tested using both simulations and experiments.


2019 ◽  
Vol 9 (2) ◽  
pp. 29-35
Author(s):  
Rachid Belaidi ◽  
Boualem Bendib ◽  
Djamila Ghribi ◽  
Belkacem Bouzidi ◽  
Mohamed Mghezzi Larafi

The main goal of maximum power point (MPP) tracking control is to extract the maximum photovoltaic (PV) power by finding the optimal operating point under varying atmospheric conditions to improve the efficiency of PV systems. In recent years, the field of tracking the MPP of PV systems has attracted the interest of many researchers from the industry and academia. This research paper presents a comparative study between the modern fuzzy logic based controller and the conventional perturb & observe (P&O) technique. The comparative study was carried out under different weather conditions in order to analyse and evaluate the performance of the PV system. The overall system simulation has been performed using Matlab/Simulink software environment. The simulation results show that the dynamic behaviour exhibited by the modern fuzzy controller outperforms that of the conventional controller (P&O) in terms of response time and damping characteristics.   Keywords: MPPT, photovoltaic system, fuzzy logic control, P&O algorithm.


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