Photovoltaic system

The use of the internet of things (IoT) in solar photovoltaic (PV) systems is a critical feature for remote monitoring, supervising, and performance
evaluation. Furthermore, it improves the long-term viability, consistency,
efficiency, and system maintenance of energy production. However, previous researchers' proposed PV monitoring systems are relatively complex and expensive. Furthermore, the existing systems do not have any backup data, which means that the acquired data could be lost if the network connection fails. This paper presents a simple and low-cost IoT-based PV parameter monitoring system, with additional backup data stored on a microSD card. A NodeMCU ESP8266 development board is chosen as the main controller because it is a system-on-chip (SOC) microcontroller with integrated Wi-Fi and low-power support, all in one chip to reduce the cost of the proposed system. The solar irradiance, ambient temperature, PV output voltage and PV output current, are measured with photo-diodes, DHT22, impedance dividers and ACS712. While, the PV output power is a product of the PV voltage and PV current. ThingSpeak, an open-source software, is used as a cloud
database and data monitoring tool in the form of interactive graphics. The results showed that the system was designed to be highly accurate, reliable, simple to use, and low-cost.

The increasing energy demand and the target to reduce environmental pollution make it essential to use efficient and environment-friendly renewable energy systems. One of these systems is the Photovoltaic (PV) system which generates energy subject to variation in environmental conditions such as temperature and solar radiations. In the presence of these variations, it is necessary to extract the maximum power via the maximum power point tracking (MPPT) controller. This paper presents a nonlinear generalized global sliding mode controller (GGSMC) to harvest maximum power from a PV array using a DC-DC buck-boost converter. A feed-forward neural network (FFNN) is used to provide a reference voltage. A GGSMC is designed to track the FFNN generated reference subject to varying temperature and sunlight. The proposed control strategy, along with a modified sliding mode control, eliminates the reaching phase so that the sliding mode exists throughout the time. The system response observes n...

Photovoltaics is a promising technology to produce sustainable energy, thanks to the high amount of energy emitted by the sun. One way of having solar cells with low production costs is to apply thin-film technology and with earth-abundant raw materials. A keen interest is arising in kesterite compounds, which are chalcogenides composed of abundant and non-toxic elements. They have already achieved excellent performance at the laboratory level. Here, we report the synthesis and characterization of mixed chalcogenides based on copper, zinc, iron, and tin. Solutions have been studied with different zinc and iron ratios. The distortion of the elementary cell of kesterite increases with the addition of iron until a phase transition to stannite occurs. The process of synthesis and deposition proposed herein is cheap and straightforward, based on the sol-gel technique. These thin films are particularly attractive for use in cheap and easily processable solar cells. The synthesized layers ...

This study investigates the techno-economic feasibility of installing a 3-kilowatt-peak (kWp) photovoltaic (PV) system in Kathmandu, Nepal. The study also analyses the importance of scaling up the share of solar energy to contribute to the country's overall energy generation mix. The technical viability of the designed PV system is assessed using PVsyst and Meteonorm simulation software. The performance indicators adopted in our study are the electric energy output, performance ratio, and the economic returns including the levelised cost and the net present value of energy production. The key parameters used in simulations are site-specific meteorological data, solar irradiance, PV capacity factor, and the price of electricity. The achieved PV system efficiency and the performance ratio are 17% and 84%, respectively. The demand–supply gap has been estimated assuming the load profile of a typical household in Kathmandu under the enhanced use of electric appliances. Our results sh...

In this project the main focus is on using MPPT control of standalone-PV with battery to supply power to the loads. The system comprises of a battery, PV panel and a boost converter circuit. The project consists of both software and hardware design. The boost converter tracks the maximum power point(MPP) of the PV panel by controlling the duty cycle and giving it as gate pulse to the boost converter whereas the function of battery is to maintain a constant dc-link voltage. The inverter is used to supply ac power to the loads. The filter is also designed to reduce the harmonics and to obtain perfect sinusoidal output, which may otherwise damage the loads, so that total harmonic distortion is according to IEEE STANDARD. Perturb and observe method is used as MPPT (Maximum Power Point Tracking) control algorithm. MATLAB SIMULINK is used to create a simulation model of the Standalone-PV system and the output is verified. After verification of simulation, the whole set up is designed in h...

In the world, energy demand continues to grow incessantly. At the same time, there is a growing need to reduce CO 2 emissions, greenhouse effects and pollution in our cities. A viable solution consists in producing energy by exploiting renewable sources, such as solar energy. However, for the efficient use of this energy, accurate estimation methods are needed. Indeed, applications like Demand/Response require prediction tools to estimate the generation profiles of renewable energy sources. This paper presents an innovative methodology for short-term (e.g. 15 minutes) forecasting of Global Horizontal Solar Irradiance (GHI). The proposed methodology is based on a Non-linear Autoregressive neural network. This neural network has been trained and validated with a dataset consisting of solar radiation samples collected for four years by a real weather station. Then GHI forecast, the output of the neural network, is given as input to our Photovoltaic simulator to predict energy production in short-term time periods. Finally, experimental results for both GHI forecast and Photovoltaic energy prediction are presented and discussed.

— At present vehicles are majorly facing two problems. One is fuel (petrol or diesel) and other is accidents. The problems due to fuel are overcome with non-conventional sources like solar, fossil fuels, etc.. Now a day's road accident is a major problem all over the world. Many innocent people are losing their lives. A majority of accidents are due to drunken driving, drowsiness and rash driving. To prevent road accidents we must have particular vehicle protection equipment. To prevent these situations, here we are designing a prototype solar powered vehicle with next generation features. In this paper we are using some sensors to detect ongoing situation like drunken and drowsiness of the driver. So when the driver was unable to handle the situation, then the vehicle will automatically take its control and automatically vehicle is protected.

The main purpose of this paper is to offer a useful battery model for simulation of stand-alone photovoltaic applications. At present, many models for battery behaviour simulation are available. Owing to the complex response of this element, these models are mainly concerned with stationary working point conditions. This paper presents an enhancement of a generic battery model, achieving a dynamic battery model for photovoltaic applications. It includes the use of automatic parameter extraction techniques and the solving of numerical calculation problems. It also introduces some new concepts, such as the maximum available capacity and the level of energy. Finally, a battery state of health estimation, has been added to complete the battery behaviour description, including non-ideal effects, such as battery capacity reduction and self-discharging current. Copyright © 2003 John Wiley & Sons, Ltd.

"The concept of injecting photovoltaic power into the utility grid has earned widespread acceptance in these days of renewable energy generation & distribution. Grid-connected inverters have evolved significantly with high diversity. Efficiency, size, weight, reliability etc. have all improved significantly with the development of modern and innovative inverter configurations and these factors have influenced the cost of producing inverters. This paper presents a literature review of the recent technological developments and trends in the Grid-Connected Photovoltaic Systems (GCPVS). In countries with high penetration of Distributed Generation (DG) resources, GCPVS have been shown to cause unwanted stress on the electrical grid. A review of the existing and future standards that addresses the technical challenges associated with the growing number of GCPVS is presented. Maximum Power Point Tracking (MPPT), Solar Tracking (ST) and the use of transform-less inverters can all lead to high efficiency gains of Photovoltaic (PV) systems while ensuring minimal interference with the grid. Inverters that support ancillary services like reactive power control, frequency regulation and energy storage are critical for mitigating the challenges caused by the growing adoption of GCPVS. Anjali | Gourav Sharma""A Review on Grid-Connected PV System"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-4 , June 2017, URL: http://www.ijtsrd.com/papers/ijtsrd2195.pdf
Article URL: http://www.ijtsrd.com/engineering/electrical-engineering/2195/a-review-on-grid-connected-pv-system/anjali"

paper  can  be  assisted  and  will  save  time  of building  a  literature about  PV  by  this  review  that  is considered  part  of  a  series  compares  the  performance  of  PV technologies.  In  this  paper,  a  comparison  survey  is  included which  investigates  the  3  generations  of  PV  cells  with  the  latest characteristics.

— A High step-up converter, which is suitable for renewable energy system, is proposed in this paper. The photovoltaic systems provide promising ways to generate clean electric power. A Full-bridge dc–dc converter with a conversion ratio around nine times, soft start-up, and soft switching features for battery charging/discharging is proposed. The converter is equipped with an active fly back and two passive capacitor–diode snubbers, which can reduce voltage and current spikes and reduce voltage and current stresses. It can achieve near zero-voltage-switching and zero-current switching Through a Fly back converter and coupled inductors; a Luo converter obtains high step-up gain without operating at extreme duty ratio. Finally, the prototype circuit with 12V input voltage, 400 V output, and 2kW output power is operated to verify its performance. The highest efficiency is 97.1%.

Harvesting solar energy using photovoltaic (PV) cells is the most simple, efficient, and reliable approach to power marine electronics.  Installing PV above or under water provides cooling that increases power conversion efficiency and cleaning. Previous work quantified the performance of PV with different submerged environments and showed promising results in harvesting available underwater solar energy. These studies were limited to commercially-available silicon-based PV. Subsequent, theoretical studies point to enormous potential of using wide-band-gap PV in underwater conditions. With this motivation, for the first time, underwater measurements using dye-sensitized solar cells (DSSCs) employing wide-bandgap ruthenium sensitizers (1.8 eV) have been carried out here. The DSSCs were fabricated and characterized under submerged conditions up to 20 cm. Four replicates provided data detailing DSSCs potential for underwater PV applications when compared with the previously collected data for mono-crystalline, poly-crystalline and amorphous silicon PV. Although the light intensity under water decreases with an increase in depths, the rate of decrease in power output for DSSMs was only 40.68%, which was less than the traditional monocrystalline and polycrystalline silicon PV by approximately 20 to 25%. Also, compared to amorphous silicon PV, DSSCs showed a slightly better performance by 2-3%, which clearly displays the capability of DSSMs to harvest indirect/diffused lights in comparison to conventional Si/thin film PV. Compared to the conventional imported-semiconductor silicon-based PV, indigenously-fabricated DSSCs using locally-sourced materials showed tremendous relative increase in performance in underwater conditions. Further work is needed to optimize DSSCs to increase absolute PCE. Even given the studies limitations, it can be concluded that with the added advantages of simple fabrication process and cost-effectiveness, DSSMs have enormous future potential for underwater PV applications.

"The general trends in the past decade of increasing solar cell efficiency, decreasing PV system costs, increasing government incentive programs, and several other factors have all combined synergistically to reduce the barriers of entry for PV systems to enter the market and expand their contribution to the global energy portfolio. The shortcomings of current inverter functions which link PV systems to the utility network are becoming transparent as PV penetration levels continue to increase. In this paper an analysis of solar system connected with the grid has been done. The system is subjected with two types of perturbations, i.e. variable load and the variable irradiance level which changes the output of the solar system. The design, modeling, and analysis of a grid-tied PV system are performed in the MATLAB software simulation environment. Solar cell works on the principle of photo voltaic effect, which has nonlinear voltage and current characteristics. These characteristics are improved with the help of maximum power point tracking (MPPT) controller. MPPT controller helps to feed the inverter with maximum power from the solar system. Results indicate that in the presence of grid disturbances the inverter can react dynamically to help restore the power system back to its normal state. A harmonic analysis was also performed indicating the inverter under study met the applicable power quality standards for distributed energy resources Anjali | Gourav Sharma""Power Quality Improvement in Grid Connected PV System"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-4 , June 2017, URL: http://www.ijtsrd.com/papers/ijtsrd2196.pdf
Article URL: http://www.ijtsrd.com/engineering/electrical-engineering/2196/power-quality-improvement-in-grid-connected-pv-system/anjali"

The Maximum Power Point Tracking (MPPT) is a technique used in power electronic circuits to extract maximum energy from the Photovoltaic (PV) Systems. In the recent decades, photovoltaic power generation has become more important due its many benefits such as needs a few maintenance and environmental advantages and fuel free. However, there are two major barriers for the use of PV systems, low energy conversion efficiency and high initial cost. To improve the energy efficiency, it is important to work PV system always at its maximum power point. So far, many researches are conducted and many papers were published and suggested different methods for extracting maximum power point. This paper presents in details implementation of Perturb and Observe MPPT using buck and buck-boost Converters. Some results such as current, voltage and output power for each various combination have been recorded. The simulation has been accomplished in software of MATLAB Math works.

In this work, the effect of some parameters on tin-based perovskite (CH3NH3SnI3) solar cell were studied through device simulation with respect to adjusting the doping concentration of the perovskite absorption layer, its thickness and the electron affinities of the electron transport medium and hole transport medium, as well as the defect density of the perovskite absorption layer and hole mobility of hole transport material (HTM). A device simulator; the one-dimensional Solar Cells Capacitance Simulator (SCAPS‑1D) program was used for simulating the tin-based perovskite solar cells. The current-voltage (J-V) characteristic curve obtained by simulating the device without optimization shows output cell parameters which include; open circuit voltage (Voc) = 0.64V, short circuit current density (Isc) = 28.50mA/, fill factor (FF) = 61.10%, and power conversion efficiency (PCE) = 11.30% under AM1.5 simulated sunlight of 100mW/cm2 at 300K. After optimization, values of the doping concent...

Renewable Energy Resources are best practices possible today to stand against increasingly risk of climate changes and global warming of the world and the most important sources of such types of resources of energies can be Wind and Solar energies which are most the efficient relatively. These clean power resources are used as in Distributed Generation (DGs) units technology to be defined as newer sources of power, which are in direct relation with the use of micro and smaller in capacity power generating units that are installed in distribution part of each power combined system or all the possible locations that loads and energy consumers are concentrated. Hybrid systems are of different states. One of the practices possible to provide these hybrids is combination of grid connected wind turbines and solar photovoltaic generators that together each could sit instead of the other one in a grid connection state when one of them cannot generate the required electricity for consumption by load properly. Moreover, Solar cells can generate the electricity required in the day while wind turbines can compensate the needs in the night by wind energy. The proposed architecture consists of solar PV and wind energy system. In solar PV system MPPT technique is applied to maximize power output, a boost converter is employed to raise DC voltage and its output is fed to a three phase PWM inverter for converting DC voltage to AC at 50Hz frequency. In wind energy conversion system Permanent Magnet Synchronous Generator (PMSG) is driven by two masse drive train based wind turbine with zero pitch angles. Simulation study of the proposed system is carried out with MATLAB Simulink and simulation results are provided.

A novel high step-up converter, which is suitable for renewable energy system is proposed in this paper. A voltage multiplier cell composed of switched capacitors and diodes. The configuration of the proposed converter not only reduces the current ripple and also increases the life span of converters. Due to the lossless passive clamp circuits, the leakage energy is recycled to the output terminals. Hence large voltage spike is avoided. Even the low voltage stress makes the low-voltage-rated MOSFETs can be adopted for reductions of conduction losses and cost. Efficiency improves because the energy stored in leakage inductances is recycled to the output terminal. This design analysis is simulated using hardware which illustrate the better performance of the converter.