This document presents a subdegree precision sun tracker designed for microconcentrator photovoltaic modules. It aims to achieve a cost target of 100€/m2 for the tracker system. A lightweight structure was designed using commercially available parts that can withstand wind speeds accounting for 95% of direct solar radiation. The tracking control relies on high accuracy solar positioning data, parameter fitting to account for installation errors, and automatic calibration of low-cost sensors against array power output. A cost analysis was conducted to compare the microconcentrator technology to conventional flat panel photovoltaics, estimating the cost of electricity based on projected module costs and efficiencies.
This document summarizes a research paper that presents a simulation of incremental conductance maximum power point tracking (IncCond MPPT) used in solar array power systems with a direct control method. The proposed system eliminates the proportional–integral control loop typically used in MPPT systems. The IncCond algorithm is used to track the maximum power points as it performs precise control under changing atmospheric conditions. Simulation results using MATLAB and SIMULINK indicate the feasibility and improved functionality of the proposed system.
This document summarizes research on predicting mismatch losses in utility-scale photovoltaic systems. The key findings are:
1) For a 1 MW array with a common 5W module power tolerance, mismatch loss is 0.501% of total power. Loss increases with wider distributions.
2) For a 5W distribution, loss decreases as array size increases up to 1.5MW, above which it remains constant.
3) For the same sized array, string inverters offer a constant, minimal advantage over central inverters with respect to mismatch. The difference in losses remains small as array size increases.
Power amplifier performance improvement using tunable matchingIAEME Publication
This document discusses improving the performance of power amplifiers in mobile devices using a tunable matching network (TMN). It begins by introducing the issues of impedance mismatch between power amplifiers and antennas in mobile devices operating over multiple frequency bands and environments. It then presents the design of a TMN using a π-network architecture with switches to cover 700-915MHz and 1500-2100MHz bands. The document evaluates the TMN connected to a multiband power amplifier in simulation. It finds that optimizing both the S11 parameter and transducer gain of the TMN improves output power by up to 3dB and power added efficiency by up to 10% under worst-case VSWR conditions compared to no TMN. The
International journal of engineering and mathematical modelling vol1 no1_2015_1IJEMM
The degradation of the weather conditions is dangerous for driving and should incite drivers to reduce the car speed. The present work solves this problem of the speed limit in city road and highway by changing automatically the authorized speed with the weather conditions.
The new developed stand-alone speed limit road sign is intelligent and is capable to analyze the weather context using sensors, and to display the most adapted speed limit according to the surrounding environment. Several scenarios have been proposed to develop a pre industrialized prototype and to analyze them according to different criteria (cost, consumption, endurance and reliability). In addition, the system is an autonomous stand alone and uses the solar energy as source of supply. The pre-industrial prototype of the system was successfully achieved. However to develop a "low cost" system a new concept of meteorological sensors was done, for the low consumption of the display we use the LED (light emitting diode) components.
1) The document describes a project to develop a lightweight, flexible solar panel that can be mounted on a backpack to recharge lithium-ion batteries for military use.
2) A key goal was to maximize power generation per unit mass and area. The panel uses gallium arsenide solar cells with an efficiency of 20-23% arranged in a 10x3 array weighing 270g.
3) Thirteen prototype systems were tested by Marines in February 2012. The tests aimed to evaluate how well the solar panels could recharge batteries under field conditions.
Concentration Photovoltaics (CPV) has experienced a large thrust in the last couple of years as it is starting to deliver very promising technologies into the market. The role played by the Institute of Concentration Photovoltaics (ISFOC) in Puertollano, Spain, has been key to the growth of the industry helping the development of the first commercial products and their deployment. Multijunction solar cells with commercial efficiencies close to 40%, innovative optical designs that minimise losses and novel approaches to the tight CPV tracking requirements are the main technical advances that are easing up the way of CPV deployment.
The ISFOC project has been financed by the Spanish Government and through the installation of up to 3MW of various CPV technologies is helping to define the standards for the industry and their evaluation of power and energy performance. Further on, ISFOC will be open for collaboration in applied research and technology on all the key areas of CPV which is to become a major sector in renewable energy generation across the globe. This webinar will review the current status of the ISFOC project and the technical and commercial opportunity for CPV.
This document summarizes a NASA internship report on developing an extendable electrostatic satellite capture arm and reactive satellite simulator. The capture arm uses electrostatic adhesion, which requires only contact and no moving parts, to manipulate satellites. It has a spiralift linear actuator for extension and an electrostatic gripper end effector. Testing showed electrostatic adhesion can manipulate various materials. A reactive satellite simulator was also designed to simulate a tumbling satellite for capture tests. The capture arm and simulator were built and tested to validate electrostatic gripping for potential in-space application.
A cellular base station antenna configuration for variable coverageIJECEIAES
The field coverage offered by the base station antenna in GSM systems influences the reception and interference performances. The coverage can be varied by scanning the mainbeam direction or varying the shape of the radiation pattern. In cellular system applications, a simple technique is desirable to achieve this goal. A simple technique to vary the coverage of cellular base station is investigated. The technique uses two conventional antennas tilted by a certain angle and fed by the same signal but at variable amplitudes. It is demonstrated that the field across one half of the covered sector can be gradually increased while that at the other half is reduced by varying the excitations of the two antenna elements. This can be deployed in a simple electronic means in response to the changing scenario rather readjusting the direction of the base station antenna.
This document summarizes a research paper that presents a simulation of incremental conductance maximum power point tracking (IncCond MPPT) used in solar array power systems with a direct control method. The proposed system eliminates the proportional–integral control loop typically used in MPPT systems. The IncCond algorithm is used to track the maximum power points as it performs precise control under changing atmospheric conditions. Simulation results using MATLAB and SIMULINK indicate the feasibility and improved functionality of the proposed system.
This document summarizes research on predicting mismatch losses in utility-scale photovoltaic systems. The key findings are:
1) For a 1 MW array with a common 5W module power tolerance, mismatch loss is 0.501% of total power. Loss increases with wider distributions.
2) For a 5W distribution, loss decreases as array size increases up to 1.5MW, above which it remains constant.
3) For the same sized array, string inverters offer a constant, minimal advantage over central inverters with respect to mismatch. The difference in losses remains small as array size increases.
Power amplifier performance improvement using tunable matchingIAEME Publication
This document discusses improving the performance of power amplifiers in mobile devices using a tunable matching network (TMN). It begins by introducing the issues of impedance mismatch between power amplifiers and antennas in mobile devices operating over multiple frequency bands and environments. It then presents the design of a TMN using a π-network architecture with switches to cover 700-915MHz and 1500-2100MHz bands. The document evaluates the TMN connected to a multiband power amplifier in simulation. It finds that optimizing both the S11 parameter and transducer gain of the TMN improves output power by up to 3dB and power added efficiency by up to 10% under worst-case VSWR conditions compared to no TMN. The
International journal of engineering and mathematical modelling vol1 no1_2015_1IJEMM
The degradation of the weather conditions is dangerous for driving and should incite drivers to reduce the car speed. The present work solves this problem of the speed limit in city road and highway by changing automatically the authorized speed with the weather conditions.
The new developed stand-alone speed limit road sign is intelligent and is capable to analyze the weather context using sensors, and to display the most adapted speed limit according to the surrounding environment. Several scenarios have been proposed to develop a pre industrialized prototype and to analyze them according to different criteria (cost, consumption, endurance and reliability). In addition, the system is an autonomous stand alone and uses the solar energy as source of supply. The pre-industrial prototype of the system was successfully achieved. However to develop a "low cost" system a new concept of meteorological sensors was done, for the low consumption of the display we use the LED (light emitting diode) components.
1) The document describes a project to develop a lightweight, flexible solar panel that can be mounted on a backpack to recharge lithium-ion batteries for military use.
2) A key goal was to maximize power generation per unit mass and area. The panel uses gallium arsenide solar cells with an efficiency of 20-23% arranged in a 10x3 array weighing 270g.
3) Thirteen prototype systems were tested by Marines in February 2012. The tests aimed to evaluate how well the solar panels could recharge batteries under field conditions.
Concentration Photovoltaics (CPV) has experienced a large thrust in the last couple of years as it is starting to deliver very promising technologies into the market. The role played by the Institute of Concentration Photovoltaics (ISFOC) in Puertollano, Spain, has been key to the growth of the industry helping the development of the first commercial products and their deployment. Multijunction solar cells with commercial efficiencies close to 40%, innovative optical designs that minimise losses and novel approaches to the tight CPV tracking requirements are the main technical advances that are easing up the way of CPV deployment.
The ISFOC project has been financed by the Spanish Government and through the installation of up to 3MW of various CPV technologies is helping to define the standards for the industry and their evaluation of power and energy performance. Further on, ISFOC will be open for collaboration in applied research and technology on all the key areas of CPV which is to become a major sector in renewable energy generation across the globe. This webinar will review the current status of the ISFOC project and the technical and commercial opportunity for CPV.
This document summarizes a NASA internship report on developing an extendable electrostatic satellite capture arm and reactive satellite simulator. The capture arm uses electrostatic adhesion, which requires only contact and no moving parts, to manipulate satellites. It has a spiralift linear actuator for extension and an electrostatic gripper end effector. Testing showed electrostatic adhesion can manipulate various materials. A reactive satellite simulator was also designed to simulate a tumbling satellite for capture tests. The capture arm and simulator were built and tested to validate electrostatic gripping for potential in-space application.
A cellular base station antenna configuration for variable coverageIJECEIAES
The field coverage offered by the base station antenna in GSM systems influences the reception and interference performances. The coverage can be varied by scanning the mainbeam direction or varying the shape of the radiation pattern. In cellular system applications, a simple technique is desirable to achieve this goal. A simple technique to vary the coverage of cellular base station is investigated. The technique uses two conventional antennas tilted by a certain angle and fed by the same signal but at variable amplitudes. It is demonstrated that the field across one half of the covered sector can be gradually increased while that at the other half is reduced by varying the excitations of the two antenna elements. This can be deployed in a simple electronic means in response to the changing scenario rather readjusting the direction of the base station antenna.
High concentration photovoltaics: potentials and challengesLeonardo ENERGY
The document summarizes key topics in high concentration photovoltaics (HCPV), including:
- HCPV aims to lower the cost of expensive III-V solar cells by reducing their area through high optical concentration.
- HCPV systems use optics to concentrate sunlight onto small, high-efficiency multi-junction solar cells.
- Advanced optics designs like free-form surfaces can provide high concentration ratios and tolerances needed for HCPV to be cost-effective.
- The document compares different HCPV systems in terms of their efficiency, concentration ratio, and acceptance angle tolerance.
IRJET- Distance Algorithm for Transmission Line with Mid-Point Connected ...IRJET Journal
This document discusses distance protection of a transmission line with a STATCOM installed at the mid-point. It begins with an introduction to FACTS devices and their impact on transmission line protection schemes. It then reviews the modeling and operation of STATCOM and distance relays. The performance of a two-zone distance protection scheme is evaluated for different fault conditions using EMTDC/PSCAD simulation. To address misoperations of the conventional distance relay when the line is compensated by STATCOM, an adaptive distance protection algorithm is presented and its flow diagram is shown. The algorithm adaptively selects the protection zones based on the STATCOM injection current and measured relay quantities to improve the reliability of distance protection.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
BridgeTech STT Corporate Presentation September 2008Peter A. Khoury
Solar Thermal Technologies presents on their solar energy technology. They aim to make solar energy cost competitive with fossil fuels through their GyroSolé system, which uses concentrated solar heat, thermal energy storage, and an innovative heat engine to generate electricity. Their technology was developed at Lawrence Livermore National Labs and they project rapid sales growth and profitability over the next 5 years as their systems target the residential and commercial markets.
A cube sat communication design for In-Space Assembly Ensaf Atef
A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. As is typical in all conventional thermal power stations the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity. The conversion to electrical energy takes place indirectly, as in conventional thermal power plants.
The document describes the development of an automatic MATLAB-based tool for measuring beam emittance at the Idaho Accelerator Center. An optical transition radiation screen and camera were installed to capture beam images during a quadrupole scan. MATLAB codes were developed to extract beam sizes from the images, perform a polynomial fit to determine emittance, and control the scan automatically via EPICS and MATLAB Channel Access. The tool was tested by measuring the emittance of the HRRL accelerator, reducing measurement time and error compared to manual methods.
A Triple Band Notched Reconfigurable Micro strip Fed UWB Applications AntennaAM Publications
-In this paper a compact ultra wide band (UWB) triple band notched reconfigurable micro strip antenna is proposed. The bands 2.6GHZ-3.11GHZ (WIMAX) and 5.0GHZ-5.6GHZ (WIFI) and 7.4-8.6(C BAND) are notched from the antenna operating frequency. The triple band notched antenna is designed by itching two slots having different shapes on the radiating patch. One slot is of T shaped and the other slot is of rectangular shaped. Design specifications for notching the desired bands are provided. The results are simulated using HFSS and compared with the experimental results which suggest that the antenna can be used very efficiently in the UWB range without much interference.
Adobe gets real (or fake) about content marketingTraction
Presentation from Traction and Adobe on 3 shifts content marketing have had on how Adobe approaches marketing. Originally presented at the 2013 iMedia Brand Summit.
The document discusses a new machine called a "Powerformer" that can generate high voltage electricity more efficiently than conventional power plants. A Powerformer is a generator that uses high voltage cables in its stator winding, allowing it to directly connect to high voltage grids without needing a step-up transformer. This improves efficiency and reduces costs compared to plants that require transformers. The first Powerformer installation was a 11 MVA, 45 kV machine connected to the grid in Sweden. Powerformers offer higher efficiency, lower maintenance costs, and better power transfer from generator to grid than conventional systems.
The document discusses electric traction systems used in India. It describes how 25kV AC power from overhead lines is transformed and converted to operate DC series motors to power electric locomotives. Three main stages are involved: an input converter transforms and rectifies AC to DC, a DC link further smoothes the power, and a drive converter generates three-phase AC for induction traction motors using thyristors. The document outlines the components and functions of the electric traction system, including catenaries, pantographs, circuit breakers, transformers, rectifiers, and DC series traction motors.
This document describes a bus tracking application for students. The application uses GPS to track the real-time location of buses and send bus locations to students when requested. It also generates predicted arrival times at stops. The application was developed using Eclipse, Android SDK, and integrates Google Maps. It has modules for location information, maps, and bus/route details stored in a MySQL database.
Electric traction involves using electric power for traction systems like railways and trams. It provides advantages over steam and diesel traction like higher power-to-weight ratio, regenerative braking, and lower emissions. Common voltages used include 1.5kV DC, 25kV AC. Traction motors are usually DC or induction types. Electrification requires overhead wires or third rails to transmit power. India uses mainly 25kV AC overhead systems like other large networks. Electric traction is more energy efficient and reduces dependence on fossil fuels.
This document describes the development of a prototype solar tracker. It presents equations to predict solar irradiance and track the sun's movement. A one-axis tracker was built using a microcontroller, motor, and sensor to align a solar panel based on the sun's position. Experimental data collected over three days showed the tracking panel generated an average of over 18% more power than a stationary panel.
A hybrid electric vehicle combines an electric motor with an internal combustion engine to improve fuel efficiency. There are two main types of hybrid configurations - parallel and series. In a parallel hybrid, both the engine and electric motor can power the wheels directly. In a series hybrid, the engine charges the battery which powers the electric motor to turn the wheels. Fuel cell hybrid vehicles use hydrogen to power an electric motor, providing emissions-free propulsion. Driving at a constant speed, avoiding abrupt stops, and driving more slowly can improve the fuel efficiency of any hybrid vehicle.
This paper discusses Inspira's work developing sun tracking control systems for concentrating photovoltaic (CPV) technologies. It presents an overview of three projects: 1) Developing the EPS-Tenerife sun tracking control unit for BP Solar's EUCLIDES one-axis CPV system using a novel hybrid sun tracking strategy. 2) Upgrading the strategy through the Ificles project to work for two-axis trackers. 3) Inspira's latest system, SunDog, which uses a general error model for one- or two-axis trackers. Reliable, low-cost sun tracking is identified as a key challenge holding back CPV technologies from widespread adoption.
Modified variable neighborhood search algorithm for maximum power point track...TELKOMNIKA JOURNAL
Photovoltaic (PV) systems are being increasingly popular for power generation from solar radiation as the usage of renewable energy grows. To improve the efficiency, the system should operate at its the maximum power point. Hence, several algorithms have been developed for this purpose. Continuous tracking for the maximum power point often leads to heavy energy loss. Furthermore, partial shading can dramatically lower the performance of the system. A modified variable neighborhood search algorithm is proposed resulting zero oscillations around the operating point. A set of variables are used to improve the system’s configurability in various atmospheric and geographical conditions. Simulation result proves the operation of the proposed algorithm, its accuracy, and its fast response time.
The MCSP system is a mobile concentrating solar power technology being developed to efficiently charge electronic devices from solar energy. It uses a ball lens and dual-axis tracking mechanism to concentrate sunlight over 500 times onto small multi-junction solar cells. This allows the system to generate enough electricity with 2.5 times less cell material than flat plate PV systems. It is designed to be compact, portable, and provide off-grid power to consumer electronics using natural resources with minimal components and maintenance.
Partial Shading in Building Integrated PV System: Causes, Effects and Mitigat...IJPEDS-IAES
This paper is aimed to provide a holistic understanding on the issues related
to partial shading: its causes, the theoretical and physical reasons behind it,
its implications on the BIPV system. Furthermore the possible mitigation
techniques using the software (MPPT) and hardware solutions are discussed.
Finally an example is given to illustrate the impact of partial shading and the
economic benefits of employing various partial shading mitigation
techniques into the BIPV system To aid the unfamiliar readers in this subject, a brief but comprehensive overview of important PV concepts are also given.
High concentration photovoltaics: potentials and challengesLeonardo ENERGY
The document summarizes key topics in high concentration photovoltaics (HCPV), including:
- HCPV aims to lower the cost of expensive III-V solar cells by reducing their area through high optical concentration.
- HCPV systems use optics to concentrate sunlight onto small, high-efficiency multi-junction solar cells.
- Advanced optics designs like free-form surfaces can provide high concentration ratios and tolerances needed for HCPV to be cost-effective.
- The document compares different HCPV systems in terms of their efficiency, concentration ratio, and acceptance angle tolerance.
IRJET- Distance Algorithm for Transmission Line with Mid-Point Connected ...IRJET Journal
This document discusses distance protection of a transmission line with a STATCOM installed at the mid-point. It begins with an introduction to FACTS devices and their impact on transmission line protection schemes. It then reviews the modeling and operation of STATCOM and distance relays. The performance of a two-zone distance protection scheme is evaluated for different fault conditions using EMTDC/PSCAD simulation. To address misoperations of the conventional distance relay when the line is compensated by STATCOM, an adaptive distance protection algorithm is presented and its flow diagram is shown. The algorithm adaptively selects the protection zones based on the STATCOM injection current and measured relay quantities to improve the reliability of distance protection.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
BridgeTech STT Corporate Presentation September 2008Peter A. Khoury
Solar Thermal Technologies presents on their solar energy technology. They aim to make solar energy cost competitive with fossil fuels through their GyroSolé system, which uses concentrated solar heat, thermal energy storage, and an innovative heat engine to generate electricity. Their technology was developed at Lawrence Livermore National Labs and they project rapid sales growth and profitability over the next 5 years as their systems target the residential and commercial markets.
A cube sat communication design for In-Space Assembly Ensaf Atef
A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. As is typical in all conventional thermal power stations the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity. The conversion to electrical energy takes place indirectly, as in conventional thermal power plants.
The document describes the development of an automatic MATLAB-based tool for measuring beam emittance at the Idaho Accelerator Center. An optical transition radiation screen and camera were installed to capture beam images during a quadrupole scan. MATLAB codes were developed to extract beam sizes from the images, perform a polynomial fit to determine emittance, and control the scan automatically via EPICS and MATLAB Channel Access. The tool was tested by measuring the emittance of the HRRL accelerator, reducing measurement time and error compared to manual methods.
A Triple Band Notched Reconfigurable Micro strip Fed UWB Applications AntennaAM Publications
-In this paper a compact ultra wide band (UWB) triple band notched reconfigurable micro strip antenna is proposed. The bands 2.6GHZ-3.11GHZ (WIMAX) and 5.0GHZ-5.6GHZ (WIFI) and 7.4-8.6(C BAND) are notched from the antenna operating frequency. The triple band notched antenna is designed by itching two slots having different shapes on the radiating patch. One slot is of T shaped and the other slot is of rectangular shaped. Design specifications for notching the desired bands are provided. The results are simulated using HFSS and compared with the experimental results which suggest that the antenna can be used very efficiently in the UWB range without much interference.
Adobe gets real (or fake) about content marketingTraction
Presentation from Traction and Adobe on 3 shifts content marketing have had on how Adobe approaches marketing. Originally presented at the 2013 iMedia Brand Summit.
The document discusses a new machine called a "Powerformer" that can generate high voltage electricity more efficiently than conventional power plants. A Powerformer is a generator that uses high voltage cables in its stator winding, allowing it to directly connect to high voltage grids without needing a step-up transformer. This improves efficiency and reduces costs compared to plants that require transformers. The first Powerformer installation was a 11 MVA, 45 kV machine connected to the grid in Sweden. Powerformers offer higher efficiency, lower maintenance costs, and better power transfer from generator to grid than conventional systems.
The document discusses electric traction systems used in India. It describes how 25kV AC power from overhead lines is transformed and converted to operate DC series motors to power electric locomotives. Three main stages are involved: an input converter transforms and rectifies AC to DC, a DC link further smoothes the power, and a drive converter generates three-phase AC for induction traction motors using thyristors. The document outlines the components and functions of the electric traction system, including catenaries, pantographs, circuit breakers, transformers, rectifiers, and DC series traction motors.
This document describes a bus tracking application for students. The application uses GPS to track the real-time location of buses and send bus locations to students when requested. It also generates predicted arrival times at stops. The application was developed using Eclipse, Android SDK, and integrates Google Maps. It has modules for location information, maps, and bus/route details stored in a MySQL database.
Electric traction involves using electric power for traction systems like railways and trams. It provides advantages over steam and diesel traction like higher power-to-weight ratio, regenerative braking, and lower emissions. Common voltages used include 1.5kV DC, 25kV AC. Traction motors are usually DC or induction types. Electrification requires overhead wires or third rails to transmit power. India uses mainly 25kV AC overhead systems like other large networks. Electric traction is more energy efficient and reduces dependence on fossil fuels.
This document describes the development of a prototype solar tracker. It presents equations to predict solar irradiance and track the sun's movement. A one-axis tracker was built using a microcontroller, motor, and sensor to align a solar panel based on the sun's position. Experimental data collected over three days showed the tracking panel generated an average of over 18% more power than a stationary panel.
A hybrid electric vehicle combines an electric motor with an internal combustion engine to improve fuel efficiency. There are two main types of hybrid configurations - parallel and series. In a parallel hybrid, both the engine and electric motor can power the wheels directly. In a series hybrid, the engine charges the battery which powers the electric motor to turn the wheels. Fuel cell hybrid vehicles use hydrogen to power an electric motor, providing emissions-free propulsion. Driving at a constant speed, avoiding abrupt stops, and driving more slowly can improve the fuel efficiency of any hybrid vehicle.
This paper discusses Inspira's work developing sun tracking control systems for concentrating photovoltaic (CPV) technologies. It presents an overview of three projects: 1) Developing the EPS-Tenerife sun tracking control unit for BP Solar's EUCLIDES one-axis CPV system using a novel hybrid sun tracking strategy. 2) Upgrading the strategy through the Ificles project to work for two-axis trackers. 3) Inspira's latest system, SunDog, which uses a general error model for one- or two-axis trackers. Reliable, low-cost sun tracking is identified as a key challenge holding back CPV technologies from widespread adoption.
Modified variable neighborhood search algorithm for maximum power point track...TELKOMNIKA JOURNAL
Photovoltaic (PV) systems are being increasingly popular for power generation from solar radiation as the usage of renewable energy grows. To improve the efficiency, the system should operate at its the maximum power point. Hence, several algorithms have been developed for this purpose. Continuous tracking for the maximum power point often leads to heavy energy loss. Furthermore, partial shading can dramatically lower the performance of the system. A modified variable neighborhood search algorithm is proposed resulting zero oscillations around the operating point. A set of variables are used to improve the system’s configurability in various atmospheric and geographical conditions. Simulation result proves the operation of the proposed algorithm, its accuracy, and its fast response time.
The MCSP system is a mobile concentrating solar power technology being developed to efficiently charge electronic devices from solar energy. It uses a ball lens and dual-axis tracking mechanism to concentrate sunlight over 500 times onto small multi-junction solar cells. This allows the system to generate enough electricity with 2.5 times less cell material than flat plate PV systems. It is designed to be compact, portable, and provide off-grid power to consumer electronics using natural resources with minimal components and maintenance.
Partial Shading in Building Integrated PV System: Causes, Effects and Mitigat...IJPEDS-IAES
This paper is aimed to provide a holistic understanding on the issues related
to partial shading: its causes, the theoretical and physical reasons behind it,
its implications on the BIPV system. Furthermore the possible mitigation
techniques using the software (MPPT) and hardware solutions are discussed.
Finally an example is given to illustrate the impact of partial shading and the
economic benefits of employing various partial shading mitigation
techniques into the BIPV system To aid the unfamiliar readers in this subject, a brief but comprehensive overview of important PV concepts are also given.
An efficient optical inspection of photovoltaic modules deploying edge detec...IJECEIAES
With the enhanced industrial and domestic energy needs, there is a great urge for renewable energy sources because of their eco-friendly nature. Solar energy is crucial among renewable energy sources and there is a great need to optimize and enhance the performance of solar energy usage that is mainly dependent on the system components. The current work has been aimed to discuss the fault detection of photovoltaic (PV) modules by evaluating an efficient, facile inspection algorithm electrical analysis for real-time applications. The paper presents a real-time experimental model for infrared thermography using a thermal imager mounted on a tripod at a suitable distance from the PV modules to capture the images in the best possible way. A novel hybrid algorithm has been proposed and the fault detection along with the electrical parameter analysis has been accurately performed on the PV modules to analyze and process various externally induced faults in the PV systems.
Sizing of Hybrid PV/Battery Power System in Sohag cityiosrjce
This paper gives the feasibility analysis of PV- Battery system for an off-grid power station in Sohag
city. Hybrid PV-battery system was used for supplying a combined pumping and residential load. A simple cost
effective method for sizing stand-alone PV hybrid systems was introduced. The aim of sizing hybrid system is to
determine the cost effective PV configuration and to meet the estimated load at minimum cost. This requires
assessing the climate conditions which determine the temporal variation of the insolation in Sohag city. Sizing
of the hybrid system components was investigated using RETscreen and HOMER programs. The sizing software
tools require a set of data on energy resource demand and system specifications. The energy cost values of the
hybrid system agrees reasonably with those published before.
The document discusses sizing a hybrid PV/battery power system in Sohag City, Egypt to meet the power demands of a combined pumping and residential load. It analyzes the feasibility of the system using the RETscreen and HOMER software programs, which require meteorological data and load profiles. The optimal system configured by HOMER consists of 25kW of PV panels, 40 batteries, and a 100kW power converter with a net present cost of $84,171 and cost of energy of $0.151/kWh.
Design of PV backup system for data centerMohamed Abbas
This document details the design of a backup PV system for a data center in Bogota, Colombia. Section I introduces the problem of weekly blackouts at the data center and the financial incentive to install a greener PV-storage backup system instead of a diesel generator. Section II discusses optimizing the panel tilt and azimuth for the location, determining the optimal configuration is 9 degrees tilt and 128 degrees azimuth. Section III analyzes the data center's load profile and effects of blackouts. Section IV provides details on selecting and sizing PV modules, charge controllers, batteries and inverters to meet the load requirements within constraints of the components.
IRJET - Maximum Power Extraction by Introducing P&O Technique in PV GridIRJET Journal
This document discusses maximum power point tracking techniques for photovoltaic systems. It begins with an introduction to MPPT and its importance for extracting maximum power from solar panels. It then describes the perturb and observe (P&O) algorithm, which is one of the most widely used MPPT techniques. The P&O algorithm periodically perturbs the operating voltage of the PV array and compares the power before and after to track the maximum power point. The document also discusses improved P&O algorithms and other techniques like incremental conductance. It provides comparisons of different MPPT methods and concludes that an adaptive step size in P&O can achieve fast tracking with minimal oscillations near the maximum power point.
IRJET- Design and Simulation of Solar PV DC Microgrid for Rural ElectrificationIRJET Journal
This document summarizes a research paper that analyzes and designs a DC microgrid system for rural electrification in India. Key points:
1) The microgrid uses distributed solar PV generation, with maximum power point tracking converters connecting the solar panels. Fanout nodes distribute power to local clusters of homes, and power management units at each home regulate usage and integrate battery storage.
2) Experimental results from a 400W prototype demonstrate the steady-state operation and stability of the system when power from the solar source is varied. The microgrid is able to maintain a stable distributed voltage while enabling power sharing between components.
3) Calculations estimate the levelized cost of electricity for the microgrid design would be lower
IRJET- Comparison between Ideal and Estimated PV Parameters using Evolutionar...IRJET Journal
This document discusses comparing the ideal and estimated parameters of photovoltaic (PV) panels using evolutionary algorithms. It begins by introducing microgrids and their importance in integrating renewable energy sources like solar PV. It then describes the ideal and practical electrical models of PV panels, noting that practical models account for additional factors. The document aims to estimate the parameters of single-diode and two-diode PV panel models using various optimization algorithms, compare the estimated models to experimental results, and compare the estimated models to the specifications provided by the panel manufacturer.
Self Electricity Generation and Energy Saving By Solar Using Programmable Sys...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Theoretical work submitted to the Journal should be original in its motivation or modeling structure. Empirical analysis should be based on a theoretical framework and should be capable of replication. It is expected that all materials required for replication (including computer programs and data sets) should be available upon request to the authors.
The International Journal of Engineering & Science would take much care in making your article published without much delay with your kind cooperation.
The document describes key components of solar tracking systems for concentrating photovoltaics (CPV), including trackers, drives, control units, and accuracy monitoring. It outlines requirements and specifications for CPV trackers. Common tracker designs are described, including a pedestal tracker designed by Inspira. Inspira's SunDog is introduced as a generic sun tracking control unit using a hybrid error model approach. Methods for monitoring sun tracking accuracy with Inspira's system based on an image sensor are also presented. Examples from testing Inspira's control units and trackers on the monitoring system are provided.
Development of Improved MPPT Algorithm Based on Balancing PSO for Renewable E...ssuser793b4e
Maximum Power Point Tracking (MPPT) is the method of operating the photovoltaic system in a manner that allows the modules to effectively transfer all the power generated from the panel to the load.Maximum Power Point (MPP) tracking technique based on Balancing Particle Swarm Optimization (BPSO) were successfully developed in this paper to solve the problem of premature convergence and also latency in convergence/tracking. The performance of the developedBPSO was evaluated at solar irradiance of 1000W/m2, 500W/m2 and 600W/m2 at constant temperatures of 25oC simultaneously.From the BPSO simulation results, it was observed that, it took the developed model0.23secs to locate the Global maxima (GP) with a very high-power output. The developed model achieved this by balancing the panel conductance with the load conductance and also compare the output power with the global peak power, if the newly output power is greater than the global peak power the MPP tracker settles at the newly detected output power but if it is less than that it maintains its previous MPP position.The developed BPSO algorithm settled at GP of 255.063W at 0.2292secs and at this point, the source impedance balances with that of the load impedance which results to negligible change in conductance. From the validation result, the convergence time of the scanningparticle swarm optimization and BPSO technique at MPP was 0.40secs and 0.23secs which showed that BPSO has42.7%relative improvementin terms of premature convergence and tracking speed. The simulation was done using 2020B MATLAB SIMULINK.
IRJET- Optimization of Renewable Energy Sources for DC MicrogridIRJET Journal
The document discusses optimization of renewable energy sources for DC microgrids. It proposes integrating wind and solar energy generation with battery storage in a microgrid connected to buildings. This hybrid system improves reliability by reducing storage needs when the generation sources have opposing output cycles. The document models and simulates such a system, showing the wind and solar outputs, storage controller, and grid connection. Integrating distributed renewable sources with storage in microgrids helps stabilize grids with intermittent generation and maximize use of transmission infrastructure.
Renewable Energy Driven Optimized Microgrid System: A Case Study with Hybrid ...IRJET Journal
This document summarizes a research study on designing an optimized hybrid microgrid system to meet the thermal and electrical demands of a building in a cost-effective way. The microgrid integrates solar PV, battery energy storage, and thermal energy storage. It was designed to reduce the building's energy consumption and carbon footprint. A case study of a campus in India analyzed reducing cooling loads by 50% using efficient chilled water and thermal energy storage. Shifting night cooling loads to daytime using thermal energy storage helped maximize solar energy use and reduce needed battery storage. The optimized microgrid design met the campus's total annual electrical load of 770,000 kWh through efficiency measures and renewable energy integration.
IRJET- Frequency Control of Distributed Generators in Microgrid with ANFIS Co...IRJET Journal
This document describes a microgrid system with distributed generators including solar panels, wind turbines, and a diesel generator. Energy storage devices like batteries and fuel cells are also included. Frequency control of the system is challenging due to varying renewable energy output. The document proposes using an Artificial Neuro-Fuzzy Inference System (ANFIS) controller to improve frequency control performance compared to conventional controllers like PI. MATLAB/Simulink models are developed to simulate the microgrid components and evaluate the ANFIS controller.
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This document summarizes a research paper on assessing the power quality of a photovoltaic (solar panel) system. It begins with an abstract stating that maximum power point tracking techniques are used to optimize solar energy production. It then provides background on photovoltaic systems, including their components like solar panels, batteries, inverters, and mounting systems. The document states that photovoltaic systems have issues with low power conversion efficiency and variability due to weather, and that maximum power point tracking techniques are used to increase efficiency by maintaining the solar panels' operating point at their maximum power point.
Proven PV Cottage Industry in Malaysia. The production of solar panel has created jobs for local community. Unlike normal solar panel factory, high capital and heavy equipments are needed. PV Cottage can contribute in generating local economy and provide localized supply of solar panels.
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Similar to A subdegree precision sun tracker for 1000 x microconcentrator modules (20)
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Automatic dynamic focusing through interfaces (abstract)Jose Miguel Moreno
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Automatic dynamic focusing through interfaces (abstract)
A subdegree precision sun tracker for 1000 x microconcentrator modules
1. A SUBDEGREE PRECISION SUN TRACKER
FOR lOOOX MICROCONCENTRATOR MODULES
lgnacio Luque-Heredia', Carlos Martin', hlaria T. Madanes', Jose M. Moreno', Josd L. Auger', Vincent Bodin',
Jeslis Alonso', Vicente Diaz', and Gabriel Sala'
1. INSPIRA, SL C/Chile, IO. 28290 Las Matas, Madrid - Spain
PhiFax: +34 91630 45 34/4087,e-mail: iluque@inspira.es
2. ISOFOTON, SA, Pol. Ind. Sta. Crur, C/La Gitanilla, 26,29006 Malaga- Spain
3. Instituto de Energia Solar, E.T.S.I. Telecomunicaci6n, Ciudad Universitaria, 28040 Madrid - Spain
ABSTRACT to come, which in many cases could profit from sunlight
concentration means when secking, at least in its first
In this paper we present a subdegree precision stages, for cost effcctiveness.
pedestal sun tracker developed for IOOOX Oriented towards one of the referred very high
microconcentrator modules. Setting a cost target of concentration attempts already on its pre-industrial stage
lOO€/m', a lightweight structure has been designed that, [7], we present here thc first prototypes of a pedestal
fully made out of commercially availablc parts, stays subdegree precision sun trackcr. This novel concentration
operative for wind speeds which account for at least 95% concept is to he rcleased with the appearance and
ofthe available direct solar radiation. dimensions of a convcntional flat PV panel, but housing
Thc electronic tracking control unit relies on a instead a parquet of IOOOX and i1.5"acceptance angle
strategy which resorts to high accuracy solar ephemeris, non-imaging lenses, which focuses on an array of Imm'
parameter fitting for a model of installation and Ill-V cells with expected module cfficicncies in the 23%
manufacturing crrors, an adaptive algorithm for absorbing to 26% range.
unforeseen or time varying errors, and automatic At the onset stagc we reckoned thc importance, in
calibration of cheap sun pointing sensors against array order to fulfil the posed cost targets, of constraining our
power output. tracker design, both drives and structure, within the
possibilities of commercially available parts, both in the
construction and automation industrics, thus avoiding
1. INTRODUCTION premiums imposed by specially manufactured
components. In the other hand bcing the manufacturing
Since in the late sevcnties, concentration systems cost of the structure mostly driven by its overall weight,
first captivated the interest of the solar community, when emphasis was placcd in lightening and additionally
it went on stage as a clear track towards strong PV cost devising efficient wind managemcnt strategies.
reduction, a reasonable amount of field cxperience has Regarding the tracking control we set off from our
been acquired which clearly keeps on pointing out its previous experience in the design and production of the
underlying tracking systems as onc of its most error pronc EPS-TENERIFETh' tracking control units for BP Solar's
components [1][2], and probably one of the overloads EUCLIDESTM concentration technology [8], based on an
which is delaying this technology's definitive industrial hybrid strategy powered by high accuracy solar ephemeris
take ofE cornplemcnted by an adaptive alignment routine.
But thc low reliability of tracking systems is not at
all unjustificd; what past PV concentration episodes have
shown is that it is really no small Sent to design tracking 2. COST ANALYSIS
structures and drives highly precise in aiming heavy loads
~ and even more with recent rising trends in the A" initial cost targct of io~€/rn'of aperture was set
concentration factors - and stiff enough to withstand for the trackcr, target which includes the tracking structure
additional wind loads. Neither is it an easy task to and drives and the tracking control unit, hut lcaves aside
develop reliable sun tracking control systems immune the cost of land, land preparation, foundation, in-field
enough to factors such as overcast and hazy skies, assembly and DC wiring.
softwarc failures, extreme weather conditions, or low cost Under this assumption and in order to perform an
low qualification installation crews. All of which is to he electricity cost comparison between present commercial
attained bound by strong cost constraints and with little flat plate technology and microconcentrator modules. we
option, in principle, to learning curvc discounts. follow the method proposed by Foetzberger and Stahl 191
Being this the situation, serious R&D effort in for the cost of cnergy estimation for tracking and non-
concentration tracking systems, will be required in order tracking PV systems, now updated with cost figures
to breed a safe mount not only for the promising very foresecn by Luque and Yamaguchi [IO] for future IOOOX
high concentration concepts now under progress in microconcentrator modules, and convcntional PV cost
different countries [3][4][5][6], hut also to ease the estimates used in recent concentration cost assessments
introduction and implementation of those aery high [Ill,(see Table I). The estimation has been made for a
efficiency 3". generation leapfrogging PV dcvelapments short term scenario. in which microconccntrator
Poster 857
2. 3rd World Confireme on Photovolruic Enrrgv Converriun Moy 11-18,2003 030ko. Japon
technology cnters the market based on GaAs one junction Being the weight of the structure highly influenced
cells, with a 265 Urn2 module, cost which is almost by the desired capability to withstand wind loads, this has
present prototype cost estimate, and a 19% module to be reasonably well set. The highest the Wind Speed
efficiency, while 550 € h z , 15% modules represent present Operative Threshold (WSOT) - the wind speed below
flat plate PV. Note that in the long term the use of W O which the tracker, whichever its position, is able to
junction cells and consideration of learning cost reduction maintain accurate tracking and over which stowing is
rates could drive to a microconcentrator module cost in the ordered the higher the direct solar radiation intake but
~
100 Wm2range and 37% module efficiencies. also the sturdier and therefore more expensive the
tracking structure results. The optimum which brings into
Table I. Data used for the cost of electricity comparison line these two opposing trends, will be the WSOT which
between IOOOX microconcentrator module technology and results in the cheapest cost of solar energy due to
conventional flat plate PV. tracking, i.e. the cumulated direct solar energy input
allowed divided by the tracker's overall cost.
Concentrarion cells ( ~ r n ~ ) . 134.000 Afler the basic structural design concept of the
Concentrarionfactor 1.000 pedestal tracker design was accomplished, a simplified
Optics, heat sink & assemblv (€/mz) 131 model was analysed to determine how the increase in its
Microconcentrotor module efficiency (%) 19 WSOT affectcd the overall tracking cost due to its
Tracking srructure, driws & control (€/mz) 100 progressive stiffening. WSOT was here defined as the
Cunventionai module (€/m') 550 threshold over which 0.1" or higher tracking error is
Conventional module efficiency P )A 15 causcd by wind load bending of the tracking structure,
Land, land preparation, foundation, in-field both pedestal and aperture. Three different aperture
assembly and DC wirinp 20 surfaces (9, 16, 25rn') were analyzcd (see Fig. 2), where
growing reinforcement was attained by escalating
Thus, "1st. generation" microconcentrator panels, structural components in a discrete manner imposed by
could result between 35% and 68% cheaper, when the constraint of only using standard commercial sizes.
compared to present flat panel photovoltaics, for which Costs estimation was performed for a preliminary low to
polar mounting is assumed, for all latitudes 60" above or medium volume industrial scenario. Linear intelpolation
below equator, and direct radiation ratios ranging from of the cost curves offer aperture cost vs. WSOT increase
50% to 80% (see Fig. I), being highest the cost premium - ratios of 0.78, 0.95 and 1.2 €/m' per kmm, respectively
the concentration to flat panel cost ratio - the highest the for 25, 16 and 9m2apertures, showing also that within this
latitudc and the sky's direct radiation ratio. range the biggest the mounted aperture the lowest the
impact of WSOT increase.
0.70 -
4 80%
- -G 70% 250 3
&SO% ~
9 m2
16 m2
-25 m2
200 4
IR = 1.20
0.35 . ~ . .- . .-. .. .
~ . ~ ~ ~
O L -
0 20 40 60 80 100
0 IO 20 30 40 50 60 WSOT (kmlb)
Latitude (")
Fig. 2 Overall tracking cost as a function of its WSOT,
Fig. 1 Cost Premium of microconcentrator technology vs. for three different aperture sizes. Linear intclpolation is
conventional flat panel as a function of latitude, for also shown giving the value of the Aperture Cost vs.
different direct solar radiation ratios. WSOT increase ratio IR.
These curves permit the deduction of the tracker's
optimum WSOT for a certain location, provided
3. WIND LOAD ASPECTS O F T H E DESIGN
cumulative direct solar radiation vs. wind speed plots can
be obtained. This type of analysis could be of use when
Steel is the cost driving factor of tracking structures,
tracker design is tailored to the specific climate of a
in such a way that when ordered in volume cost is mainly
determined by weight. In order to converge towards the certain location, which could be justified in case of
medium to big size plants.
referred cost target, weight optimization was sought for
In this direction a case study was performed for
the tracking structure.
Granada (Sp.) in order to determine the optimum WSOT
858 Poster
3. 3rd World Conference on Phoruvoltnic Energv Conversion May /I-18, 2003 Osaka. Jnpon
for a 9m2 aperture model from its cost point of view. One aperture, have been built up to know in which other
year ofcontinuous hourly direct radiation, and wind speed driving and structural variations have been tested (see Fig.
and direction measurements were used for this analysis 3).
which revealed that almost 95% of the yearly direct solar Load simulation, both due to extreme winds and
energy could be captured with a WSOT of 15 kmih and concentrating modules, in the form of distributed sand
that the cheapest WSOT was 25 kmih which would allow bags have been applied to these prototypes in order to
capture of up to 99% of the yearly direct radiation. validate design targets and calibrate CAD Finite Element
Taking a less location sensitive and more general tools. Monitoring of the tracking stmchre elastic
approach, a 43 kmPn WSOT was chosen for our design, behaviour under real wind conditions, is at present being
which permits a worst case 95% direct radiation performed in a LabviewT" environment gathering data
availability, within the big climatic variability inside the from an on-site meteorological station, the systems wind
US limits, as can be derived from the data tapes generated sensors, and high precision inclinometers placed on the
by the US National Climatic Center SOLMET stations shucture.
[121. The extra-costs due to its subdegree accuracy
A system of low cost wind speed sensors have been requirements were analysed, to get a cost comparison to
developed in order to stow the tracker whenever wind conventional flat pancl sun trackers. The analysis was
speed grows over the tracker's WSOT. Reliability is done for the three referred aperture sizes, defining the 43
granted to the system through redundancy in the k d h WSOT for three different conditions: 0.1". I" and
measurements. This system is also capable of breakage bending. This analysis shows that 0.1" stiffness
simultaneously providing global radiation measurements means an extra cost of 20-30 €lm2 over I" or breakage
in the aperture plane, which are used by the tracking conditions which are scarcely I Urn2 apart wherever
control strategy. breakage overcomes in the 3" range.
4. TRACKING STRUCTURE AND DRIVES 5. THE TRACKING CONTROL UNIT
A pedestal configuration was chosen due to its In order to avoid the detected flaws of outright open
relative low cost single point foundation, whcn compared or closed loop strategies employed in the past 1131, a
to other options such as tilt-roll. The pedestal option also hybrid improved method has been developed which resorts
permits reductions of on-site assembly work, which to an assortment of algorithms of proven efficiency.
usually dominate installation costs.
Fig. 3 9m' aperture prototype of the pedestal tracker
Dummy panels with centred hanging sand bags simulate
its real operative load.
Fig. 4 Two examples of the error transform applied to a
Standard I-beams, channels, and structural tubing,
commercially available in the construction industry rectangular grid in the azimuth-elcvation plane
determined by the four angle vector (upper figure
compose the structure, avoiding the cost surcharge
lower graph (0'. 15°,00,Z50))
(O~So,0~,Oo),
required by specifically manufactured parts.
Non back-driving drives arc chosen for both axes; a
Taxonomy of errors for ephemeris based open loop
screw jack is used for the elevation axis, while the azimuth
movement is provided by a worm and worm gear set sun tracking was first done. An specific error model which
which makes the tube holding up the aperture, to turn accounts for all characterization errors, bath stcmming
around an inner concentric post to which it is kept coupled from manufacturing and in-field installation, but leaving
by rolling contact hearings. Three prototypes, 9 m' in aside those which derive from the drive & positioner
Poster 859
4. 3rd World Con/rrence on Fhotovolraic EnergV Conversion Mu.v 11-18,2003 Osaka Jamn
which can he partly suppressed with primary axis position 6. ACKNOLEDGEMENTS
feedback, is derived based on four angles, whose
transforms over the azimuth elevation-plane have been This work has partly been funded by the Direccion
studied (see Fig. 4). General de Investigacion of the Consejeria de Educacibn
AAer a tracking error measurement session, the four de la Comunidad de Madrid under contract no
parameters of the error model are fitted using a nonlinear 09/0105/2000.
least-squares routine. Two error measurement strategies
can be selected depending on the feedback signal used:
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