Energy Acquisition of Solar-Powered Joint-Wing Aircraft Considering Mismatch Power Loss

Solar-powered aircraft can perform long-term flights with clean solar energy. However, the energy derived from solar irradiation is influenced by the time of year and latitude, which limits the energy acquisition ability of solar aircraft with a straight-wing configuration. Hence, unconventional configurations based on increasing wing dihedral to track the sun are proposed to improve energy acquisition at high-latitude regions in winter, which may involve power loss caused by mismatch in the photovoltaic system. However, mismatch loss is seldom considered and may cause energy to be overestimated. In this paper, the energy acquisition characteristics of a joint-wing configuration are presented based on the simulation of an energy system to investigate the mismatch power loss. The results indicate a 4~15% deviation from the frequently used estimation method and show that the mismatch loss is influenced by the curved upper surface, the severity of shading and the circuit configuration. Then, the configuration energy acquisition factor is proposed to represent the energy acquisition ability of the joint-wing configuration. Finally, the matching between the aircraft configuration and flight trajectory is analyzed, demonstrating that the solar-powered aircraft with an unconventional wing configuration is more sensitive to the coupling between configuration and trajectory.

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Solar Energy System for Brunei Residence

International Journal of Engineering Materials and Manufacture ◽

10.26776/ijemm.06.04.2021.07 ◽

2021 ◽

Vol 6 (4) ◽

pp. 312-318

Author(s):

Mohammad Yeakub Ali ◽

Ahmad Syahmi Rahim ◽

Seri Rahayu Ya'akub

Keyword(s):

Solar Energy ◽

Energy System ◽

Simulation Software ◽

Production Performance ◽

Photovoltaic System ◽

Solar Irradiation ◽

Energy Demands ◽

Brunei Darussalam ◽

Electrical Demand ◽

Solar Photovoltaic System

Brunei Darussalam is a country that receives high amounts of solar irradiation annually as it is located near the equator. With the abundance of oil & natural gas resources, the country has one of the cheapest electricity costs in the world. This would in turn make solar power underutilized. The purpose of this project is to design a solar system for Bruneiâ€™s medium sized residence to meet the daily energy demands. A comprehensive analysis was conducted on the solar photovoltaic system for determining the optimum sized parts and components. The design process was divided into detailed sections so that the values are calculated using PVSyst simulation software. The simulation also predicted the specific energy production, performance evaluation, and the losses. Cost analysis was also conducted to find the efficiency and the feasibility of the system. The designed solar energy system has a capacity of 60 kWp, producing 75 MWh of usable energy annually. This system uses 66% of the energy available from the sun to generate electricity which covers the electrical demand of Bruneiâ€™s residences.

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Photovoltaics: Reviewing the European Feed-in-Tariffs and Changing PV Efficiencies and Costs

The Scientific World JOURNAL ◽

10.1155/2014/404913 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

H. L. Zhang ◽

T. Van Gerven ◽

J. Baeyens ◽

J. Degrève

Keyword(s):

Electricity Generation ◽

Photovoltaic System ◽

Process Efficiency ◽

Solar Irradiation ◽

Energy Potential ◽

Levelized Cost ◽

Cost Of Energy ◽

Sustainable Electricity ◽

Near Future

Feed-in-Tariff (FiT) mechanisms have been important in boosting renewable energy, by providing a long-term guaranteed subsidy of the kWh-price, thus mitigating investment risks and enhancing the contribution of sustainable electricity. By ongoing PV development, the contribution of solar power increases exponentially. Within this significant potential, it is important for investors, operators, and scientists alike to provide answers to different questions related to subsidies, PV efficiencies and costs. The present paper therefore (i) briefly reviews the mechanisms, advantages, and evolution of FiT; (ii) describes the developments of PV, (iii) applies a comprehensive literature-based model for the solar irradiation to predict the PV solar energy potential in some target European countries, whilst comparing output predictions with the monthly measured electricity generation of a 57 m² photovoltaic system (Belgium); and finally (iv) predicts the levelized cost of energy (LCOE) in terms of investment and efficiency, providing LCOE values between 0.149 and 0.313 €/kWh, as function of the overall process efficiency and cost. The findings clearly demonstrate the potential of PV energy in Europe, where FiT can be considerably reduced or even be eliminated in the near future.

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Flight Strategy Optimization for High-Altitude Solar-Powered Aircraft Based on Gravity Energy Reserving and Mission Altitude

Applied Sciences ◽

10.3390/app10072243 ◽

2020 ◽

Vol 10 (7) ◽

pp. 2243 ◽

Cited By ~ 3

Author(s):

Mou Sun ◽

Xinzhe Ji ◽

Kangwen Sun ◽

Ming Zhu

Keyword(s):

High Altitude ◽

Trajectory Optimization ◽

Optimization Problem ◽

Kinematic Model ◽

Three Dimensional ◽

Energy System ◽

Solar Irradiation ◽

Gravity Potential ◽

Energy Store ◽

Solar Powered

High-altitude long-duration (HALE) flight capability is one of the ultimate goals pursued by human aviation technology, and the high-altitude solar-powered aircraft (SPA) is the most promising technical approach to achieve this target as well as wide application prospects. Due to the particularity of the energy system, the flight strategy optimization through the storage of gravity potential energy and other methods is a significant way to enhance the flight and application abilities for the SPA. In this study, a flight strategy optimization model has been proposed for the aim of HALE flight capability, which is based on the gravity energy reserving and mission altitude in practical engineering applications. This integrated model contains the five flight path phase model, the three-dimensional kinematic model, aerodynamic model, solar irradiation model and energy store and loss model. To solve the optimization problem of three-dimensional flight strategy, the Gauss pseudo-spectral Method (GPM) was employed to establish and calculate the optimal target as its advantages in treating process constraints and terminal constraints for the multiphase optimization problem. At last, the flight trajectory optimization with minimal battery mass for Zephyr 7 was studied by the GPOPS with some function files in MATLAB. The results indicate that the Zephyr 7 can reduce the battery mass from 16 kg to 12.61 kg for the day and night cycle flight and missions, which equals to increasing the battery specific energy by 23.1%. Meanwhile, the optimization results also show that the attitude angel may contribute to increasing the energy gained by photovoltaic cells. In addition, this optimized flight strategy brings the possibility of monthly or annual continuous flight for SPA as the simulation date is set to the autumnal day.

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Monitoring Effects of Catchment Management Practices on Phosphorus Loads into the Eutrophic Peel-Harvey Estuary, Western Australia

Water Science & Technology ◽

10.2166/wst.1986.0180 ◽

1986 ◽

Vol 18 (4-5) ◽

pp. 53-61 ◽

Cited By ~ 4

Author(s):

P. B. Birch ◽

G. G. Forbes ◽

N. J. Schofield

Keyword(s):

Management Practices ◽

Major Change ◽

High Flow ◽

Catchment Management ◽

Flow Rates ◽

Early Results ◽

Phosphorus Loads ◽

Time Of Year ◽

High Runoff

Early results from monitoring runoff suggest that the programme to reduce application of superphosphate to farmlands in surrounding catchments has been successful in reducing input of phosphorus to the eutrophic Peel-Harvey estuary. In the estuary this phosphorus fertilizes algae which grow in abundance and accumulate and pollute once clean beaches. The success of the programme has been judged from application of an empirical statistical model, which was derived from 6 years of data from the Harvey Estuary catchment prior to a major change in fertilizer practices in 1984. The model relates concentration of phosphorus with rate of flow and time of year. High phosphorus concentrations were associated with high flow rates and with flows early in the high runoff season (May-July). The model predicted that the distribution of flows in 1984 should have resulted in a flow-weighted concentration of phosphorus near the long-term average; the observed concentration was 25% below the long-term average. This means that the amount of phosphorus discharged into the Harvey Estuary could have been about 2 5% less than expected from the volume of runoff which occurred. However several more years of data are required to confirm this trend.

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Temporal load resolution impact on PV/grid system energy flows

MATEC Web of Conferences ◽

10.1051/matecconf/201824004003 ◽

2018 ◽

Vol 240 ◽

pp. 04003 ◽

Cited By ~ 5

Author(s):

Marek Jaszczur ◽

Qusay Hassan ◽

Janusz Teneta

Keyword(s):

Temporal Resolution ◽

System Analysis ◽

Estimation Error ◽

Energy System ◽

Photovoltaic System ◽

Acquisition Time ◽

Storage Unit ◽

Time Step ◽

Energy Flows ◽

Pv Grid

In this paper, an investigation of the electrical load temporal resolution on the PV/Grid energy system flows, and self-consumption is done in order to determine the optimum parameters for modelling and simulation. The analysed PV/Grid power systems include a photovoltaic system with the nominal power of Pmax@STC=1.5, 2.5, 3.5 kW without storage unit connected to the grid. The results show that the temporal load resolution may have a high impact on energy flows as well as can be a critical issue for the system analysis accuracy even for the single household. It has been found that the load temporal resolution for energy consumption of 1-min yields reliable results, while data resolutions of 5 and 15 min are still sufficient, however, in that case, the daily electrical energy flows and in consequence energy self-consumption estimation error for selected days may exceed 15%. Acquisition time step longer than 15-minutes may increase error above 20% and from the designer’s point of view should not be used. The high and low temporal resolution experimental data of the electricity consumption (load) for a household are available in digital form on the author’s website http://home.agh.edu.pl/jaszczur.

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A Novel DSP-Based MPPT Control Design for Photovoltaic Systems Using Neural Network Compensator

Energies ◽

10.3390/en14113260 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3260

Author(s):

Ming-Fa Tsai ◽

Chung-Shi Tseng ◽

Kuo-Tung Hung ◽

Shih-Hua Lin

Keyword(s):

Neural Network ◽

Maximum Power ◽

Photovoltaic System ◽

Solar Irradiation ◽

Maximum Power Point ◽

Point Tracking ◽

Power Point Tracking ◽

Irradiation Cell ◽

Power Point ◽

Neural Network Compensator

In this study, based on the slope of power versus voltage, a novel maximum-power-point tracking algorithm using a neural network compensator was proposed and implemented on a TI TMS320F28335 digital signal processing chip, which can easily process the input signals conversion and the complex floating-point computation on the neural network of the proposed control scheme. Because the output power of the photovoltaic system is a function of the solar irradiation, cell temperature, and characteristics of the photovoltaic array, the analytic solution for obtaining the maximum power is difficult to obtain due to its complexity, nonlinearity, and uncertainties of parameters. The innovation of this work is to obtain the maximum power of the photovoltaic system using a neural network with the idea of transferring the maximum-power-point tracking problem into a proportional-integral current control problem despite the variation in solar irradiation, cell temperature, and the electrical load characteristics. The current controller parameters are determined via a genetic algorithm for finding the controller parameters by the minimization of a complicatedly nonlinear performance index function. The experimental result shows the output power of the photovoltaic system, which consists of the series connection of two 155-W TYN-155S5 modules, is 267.42 W at certain solar irradiation and ambient temperature. From the simulation and experimental results, the validity of the proposed controller was verified.

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