Loading...
Search for:
photovoltaic-system
0.012 seconds
Total 84 records
Fast and simple open-circuit fault detection method for interleaved DC-DC converters
, Article 7th Power Electronics, Drive Systems and Technologies Conference, PEDSTC 2016, 16 February 2016 through 18 February 2016 ; 2016 , Pages 440-445 ; 9781509003754 (ISBN) ; Zolghadri, M. R ; Ouni, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Interleaved DC-DC boost converters are interesting choices in applications like fuel cells and photovoltaic systems. Although this converter offers low current ripple, but an open-circuit switch fault can lead to unacceptable current ripples. In this paper, a very fast and simple method is proposed to detect an open-circuit switch fault and its location. This method doesn't need any additional sensors, is efficient in CCM and DCM modes of operation, and can detect the fault in less than one switching period. Moreover, this method is suitable for implementation on an FPGA, due to the use of simple math and state machine blocks. Simulations are carried out to validate the effectiveness of this...
Explicit degradation modelling in optimal lead-acid battery use for photovoltaic systems
, Article IET Generation, Transmission and Distribution ; Volume 10, Issue 4 , 2016 , Pages 1098-1106 ; 17518687 (ISSN) ; Rajabi Ghahnavieh, A ; Sharif University of Technology
Institution of Engineering and Technology
2016
Abstract
Lead-acid battery is a storage technology that is widely used in photovoltaic (PV) systems. Battery charging and discharging profiles have a direct impact on the battery degradation and battery loss of life. This study presents a new 2-model iterative approach for explicit modelling of battery degradation in the optimal operation of PV systems. The proposed approach consists of two models: namely, economic model and degradation model which are solved iteratively to reach the optimal solution. The economic model is a linear programming optimisation problem that calculates the optimal hourly battery use profile based on an assumed value of the battery degradation cost. The degradation model,...
Optimal deployment of renewable electricity technologies in Iran and implications for emissions reductions
, Article Energy ; Volume 91 , 2015 , Pages 882-893 ; 03605442 (ISSN) ; Shafiei, E ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
In this paper, special focus is paid to the long-term adoption of renewable electricity technologies and their implications for emissions reductions in Iran. MESSAGE, as a bottom-up energy supply optimization model, is used to assess the lowest-cost technology options. The potential impacts of transitioning to a renewable electricity supply are quantified, and the investment requirement to achieve a low-carbon generation mix is estimated. Alternative scenarios are defined to evaluate the impact of fossil fuel prices, the carbon tax and government incentives on the utilization of renewable resources, national renewable targets, and emissions reductions. The prioritization of non-hydro...
Incorporation of CsPbI3 Perovskite Quantum Dots as Interrfacial Layer for Highly Efficient Cs0.05MA0.95PbI3 Perovskite Solar Cells
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
Despite the excellent photovoltaic performance of perovskite solar cells (PSCs), the instability of PSCs under severe environment (e.g., humidity, intense light) limits further commercialization of such devices. Therefore, in recent years, many researches are conducted on utilizing Perovskite Quantum Dots (PQDs) to enhance performance of PSCs. Herein, CsPbI3 PQDs interfacial layer is incorporated in the perovskite/hole transport material (HTM) interface, on the purpose of increasing charge carrier mobility and preventing electron-hole recombination to increase performance of the PSCs. CsPbI3 PQDs is synthesized at 170℃ with oleic acid and oleylamine as organic ligands by hot-injection...
Scenario Evaluation for Nearly Net Zero Energy Greenhouse Considering Photovoltaic, Industrial Symbiosis and Ground to Air Heat Transfer
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
To meet the high energy demand in greenhouse cultivation, clean technologies have been suggested. This research provides a computational and modeling framework to examine the integration of three systems including a photovoltaic panel, earth_air heat exchanger, and industrial symbiosis, to produce three types of energy (electricity cooling, and heating) in a Venlo-type greenhouse. To estimate the minimum energy required to maintain environmental parameters in optimal plant conditions, an energy demand model was developed with the ability to consider the effect of energy stored in the ground. For a greenhouse in Tehran, the annual heating requirement was calculated as 432 kWh/m2 and 227...
Design and Optimization of Floating Structure in Floating Solar Power Plants
, M.Sc. Thesis Sharif University of Technology ; Abbaspour Tehrani, Majid (Supervisor) ; Khorasanchi, Mahdi (Supervisor)
Abstract
In the initial part of this research, 10 selected dams out of 647 existing dams in Iran were selected using ArcGIS software, based on 3 indicators of height above sea level, temperature, horizontal solar radiation and wind speed, and the shadow model was calculated by calculating the radiation angle. The solar radiation on the reservoir water level of one of the selected dams, which is Durood Zan Dam, was checked on 4 days of the year. In the next stage, the design of the floating part of the power plant and its related components, in 3 parts including the main door, the door The pontoon and the main pontoon were done. Platform dimensions were optimized during the design process and to...
Design of an Integrated Iot and Renewable Energy System to Optimize Fuel Consumption In a Container Ship
, M.Sc. Thesis Sharif University of Technology ; Abbaspour, Madjid (Supervisor) ; Khorasanchi, Mahdi (Supervisor)
Abstract
One of the main methods to reduce fuel consumption and emissions is using renewable energy resources. This research proposes a hybrid renewable energy system on a container ship which includes one photovoltaic solar system, and one kite system. The photovoltaic system produces a part of the ship's electric power consumption and the kite system produces propulsion force using wind energy and transmitting this force to the ship through towing rope. Different components of these renewable energy systems are connected with the internet of things technology. In the internet of things structure design section, in addition to the conceptual design of different layers with emphasis on the processing...
Expansion Planning of Active Distribution Networks in the Gradual PV
Increase
,
M.Sc. Thesis
Sharif University of Technology
;
Ehsan, Mehdi
(Supervisor)
Abstract
Due to the increasing influence of distribution generation , their effect in planning can't be ignord , especially solar panels ,which are incresing rapidly. The main purpose of this thesis is to an active distribution network that annually load bus and the amount of photovoltaic production in it increases and plan dynamically. In the planning that is done , uncertanty in the amount comsumption load and uncertanty in the pattern of sunlight and also annual innterest rates in the classical system we have planned by optimizing the network expansion costs , in addition to supplying the load bus, we can keep the voltage drop bus and line filling within the allowable . To do this , we considered...
Fabrication and Characterization of Cu2SnS3 and Cu2ZnSnS(e)4 Absorber Layers by Spray Pyrolysis Method
, M.Sc. Thesis Sharif University of Technology ; Mahdavi, Mohammad (Supervisor)
Abstract
The Cu2ZnSnS(e)4 (CZTS(e)) quaternary and Cu2SnS3 (CTS) ternary componds with suitable optical and electrical properties have been considered as an emerging semiconductors for fabrication of thin-fim solar cells. So far, two technologies based on CdTe and CuInGaS(e)2 absorbers have achived efficiencies above 20%. However, these compounds contain toxic element Cd and rare elements such as In and Ga which, limited the development of these solar cells.In this research a 3-stage method was used for fabrication of CZTS(e) thin Films. In the first stage, CTS layers were deposited by spray pyrolysis method, in the second one, ZnS layers were also deposited on CTS layers by spray pyrolysis method...
Analysis and Improvement of Grid Voltage Quality Issues in Presence of High PV Penetration
, M.Sc. Thesis Sharif University of Technology ; Parniani, Mostafa (Supervisor)
Abstract
Nowadays, concerns about the reduction of fossil fuels and environmental issues, have made renewable resources more important. Among these resources, photovoltaic (PV) systems are more popular than others, due to their environmental compatibility and unlimited availability of sunlight. Increasing the penetration level of PV systems in electricity networks presents various technical and control challenges such as voltage and frequency variations; and protection and harmonics issues. In this thesis, voltage rise problem due to reverse power flow in distribution feeders is discussed. This is one of the main obstacles to the expansion of these resources in distribution networks.Various solutions...
Replacement of Pt with Graphene Derivatives in Counter Electrode of Dye-Sensitized Solar Cells
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Mohammad Reza (Supervisor) ; Askari, Masoud (Supervisor)
Abstract
Dye-Sensitized solar cells are the third generation of solar cells that have the potential to increase efficiency as much as solar cells of previous generations, along with lower prices. The cathode electrode of the pigmented solar cell as one of the essential components of the cell plays the role of accelerating the oxidation reaction reduction of the electrolyte. Platinum often is used as a catalyst layer. To reduce production costs and maintain cell viability, platinum should replace with other materials at a lower cost and higher electrochemical activity. Recently, carbon materials have been considered for the production of inexpensive solar cells with suitable performance. Among...
Simulation and Implementation of Active Energy Management Algorithm on Residential Photovoltaic System with Storage
, M.Sc. Thesis Sharif University of Technology ; Abbaspour, Ali (Supervisor)
Abstract
In majority of the (standalone or grid-connected) PV Systems, predefined rule-based algorithms are utilized in order to manage and control the flow of power. The function of these algorithms is to send the generated energy from solar panels either to load for consumption, or to battery for storage, or to the grid for sale. Their performance is based on predefined instructions and regardless of load change and consumption patterns. Therefore the total efficiency of these systems depend greately upon individual user’s load type and consumption pattern. In current research, an optimum and dynamic energy management algorithm is proposed using dynamic programming (DP) method, in order to increase...
Design and Implementation of a Modular 3-Ph Grid Connected Solar Inverter
, M.Sc. Thesis Sharif University of Technology ; Zolghadri, Mohammad Reza (Supervisor) ; Attarodi, Mojtaba (Co-Supervisor)
Abstract
Recently a new topology, namely “common ground inverter” is introduced which since it enjoys a direct connection between AC neutral and DC ground, essentially solves the problem of leakage current in grid connected applications. Moreover, a reduced implementation price and a simple control scheme is associated with this system. The Aforementioned features have absorbed a lot of attention for further research regarding this topology. In this research one of the three introduced topologies is considered in details and its function in supplying local loads and Grid is put to the test. Moreover, important efforts have been taken to improve the properties of the inverter in terms of efficiency,...
Performance Improvement of Grid-connected Quasi-Z-Source Photovoltaic Inverter to Reduce Leakage Currents
, Ph.D. Dissertation Sharif University of Technology ; Zolghadri, Mohammad Reza (Supervisor)
Abstract
A quasi-Z-source inverter is a beneficial structure in photovoltaic applications. In a transformerless grid-connected inverter system, the common-mode voltage fluctuations cause the leakage current flow through the ground. The low-frequency harmonics of the common-mode voltage results in the malfunction of the residual current device. On the other hand, the high-frequency harmonics of the common-mode voltage cause EMI problems, additional loss and disturbance in the output currents. In this thesis, some methods are presented to reduce the leakage current in a three-phase quasi-Z-source inverter. First, different shoot-through implementation methods are investigated. By modifying the number...
Design and Analysis of DC-DC and DC-AC Photovoltaic Converter
,
M.Sc. Thesis
Sharif University of Technology
;
Atarodi, Mojtaba
(Supervisor)
;
Zolghadri, Mohammad Reza
(Supervisor)
Abstract
Over the past decade there has been dramatic increase in fossil fuel’s usage; As a consequence, world now faces problems such as: air pollution, climate change, global warming and ozone layer depletion. In addition, depletion of the fossil energy resources is growing as a serious issue. Renewable energy(RE) sources are the most promising solution to these problems. Global investment in clean energy was increased by 16% in 2014 and solar power is anticipated to become the world’s largest source of electricity by 2050 .The German government has planned to achieve a goal of 8 percent renewables for gross power consumption by 2050 .RE is still more expensive than traditional one and faces a...
Fabrication of Nanostructure Cuprous Oxide Films for Photovoltaic Systems
, Ph.D. Dissertation Sharif University of Technology ; Iraji Zad, Azam (Supervisor) ; Mohammadpour, Raheleh (Supervisor)
Abstract
Metal oxide semiconductors are promising materials for photovoltaic systems, because they are chemically stable, almost non-toxic and abundant. These materials are cheap and have low cost fabrication process. Cu2O is the most popular metal oxide semiconductor to absorb light in Photovoltaic (PV) applications, and photocathode in the photoelectrochemical systems.In this project, thermal oxide and electrodeposition methods, both interesting and cheap, were applied for preparing Cu2O films. As inexpensive materials results in low-minority carrier diffusion length, we report on surface engineering of bulk Cu2O photocathode thorough employing nanorods of copper oxide with the average lengths of...
Experimental Investigation of Photovoltaic/thermal-Thermoelectric Hybrid System with Phase Change Material
, M.Sc. Thesis Sharif University of Technology ; Shafiee, Mohammad Behshad (Supervisor) ; Borooshaki, Mehrdad (Supervisor)
Abstract
Nowadays energy consumption increases in our daily life and incredibly enhancement of growth rate can be seen recent years. Hence, the use of renewable energy is prioritized. Solar energy is one of the choices because it is free and available. In this research, it has been tried to get electrical and thermal power at a reasonable cost both during the day and night. The system is equipped with a linear parabolic concentrator with a collector installed in the center of the concentrator which has been installed on its faces photovoltaic cells and thermoelectric modules, and five different systems have been tested with different components. Also, the paraffin has been used as a phase change...
Designing a Smart Micro-grid Connected to Solar PV System for the Energy Department of Sharif University and Developing a Web-based Software for Management
, M.Sc. Thesis Sharif University of Technology ; Boroushaki, Mehrdad (Supervisor) ; Roshandel, Ramin (Supervisor)
Abstract
This project aims to design a smart microgrid connected to the utility grid in order to supply the demand of Energy Engineering Department at Sharif University of Technology. The electrical structure of this micro-grid is included utility grid, photovoltaic system with energy storage system and a consumer. Due to the energy storage system, an operation strategy is presented that is proportionate to the installed capacities in microgrid and based on a price basis that is determined by the micro-grid operator at the beginning of each day, in order to manage energy is provided. Micro-grid energy management is divided into two sections that the implementation of each part is depended to the...
Simulation and Techno–Economical Analysis of an Improved Integrated Concentrated Photovoltaic/Organic Rankine Cycle System
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
The combination of photovoltaic technology and Organic Rankine Cycle reduces the temperature of the solar panel and, on the other hand, generates separate electricity from excess heat. The reason for the use of the Organic Rankine Cycle is the low temperature of the heat source. It is not economical to use other cycles like steam Rankine cycle in low-temperature heat sources. To maximize the plant factor of the Organic Rankine cycle system, especially when there is not enough solar radiation, it is possible to utilize the flue gas heat recovery in office buildings and reduce the cost of electricity generation. In this project, the simulation of this system is carried out for the Energy...
Decentralized Active Power Management in PV/Battery Hybrid Source Islanded Microgrids
, Ph.D. Dissertation Sharif University of Technology ; Oraee, Hashem (Supervisor)
Abstract
Due to environmental concerns and continuous decrease in the price, photovoltaic (PV) generations have been increasing in the recent years. PV units can operate in grid-connected or islanded modes. In grid-connected mode, the PV unit delivers its generated power to the grid; on the other hand, in islanded mode, it supplies the local loads. In this research, a new decentralized power management and load sharing method for a photovoltaic based islanded microgrid consisting of various PV units, battery units and hybrid PV/battery units is proposed. Unlike the previous methods in the literature, there is no need to communication among the units and the proposed method is not limited to the...