Output Power Of Solar Array Research Articles

Mission-oriented dynamic reconfiguration of airborne photovoltaic array based on multidisciplinary model

The solar-powered stratospheric airship is demonstrated overwhelming superiority because of affordable cost, recyclable material and low carbon emission. Progress has been made in the schemes of energy system consisting of curved photovoltaic array, storage, and energy management devices. However, research on various flight conditions and the resulting presence of non-uniform irradiance on the airborne solar array is rare. Moreover, the methods to reduce the power losses of on-board solar array are not investigated. This paper proposed a dynamic reconfiguration method to improve the output performance of on-board solar array in different mission conditions. The partial shading conditions of airborne and ground-based solar arrays are compared. The multiple traveling salesman problem with solar array is introduced. The Simulated annealing algorithm is adopted. The real-time optimization of solar array is obtained with the dynamic reconfiguration method according to the operating condition consisting of various parameters. The results show the proposed method effectively improves the output power of solar array compared with common total-cross-tied connections. The improvements of daily output energy of the airborne array are more than 13.7 %. The work provides a conducive reference for realizing the utilization prospect of solar energy system on aerial vehicles in a low carbon future.

Online Learning-Based Surrogate Modeling of Stratospheric Airship Solar Array Output Power

The stratospheric airship is a type of aerostat that uses solar energy as its power source and can fly continuously for months or even years in near space. The rapid and accurate prediction of the output power of its solar array is the key to maintaining energy balance and extending flight time. This paper establishes an online learning model for predicting the output power of the solar array of stratospheric airships. The readings of radiometers arranged on the surface of the airship are used as features for training the model. The parameters of the model can be updated in real-time during the flight process without retraining the entire model. The effect of radiometer placement on the model accuracy was also analyzed. The results show that for the continuous flight of 40 days, the online learning model can achieve an accuracy of 88% after training with 10 days of flight data and the accuracy basically reaches its highest level after 20 days. In addition, placing the radiometers at the four corners of the array can achieve a higher prediction accuracy of 95%. The online model can also accurately identify and reflect the effect of module efficiency attenuation or damage and maintain high accuracy.

Performance analysis of winnowing dynamic reconfiguration in partially shaded solar photovoltaic system

To extract maximum power out of solar PV array when there is partial shadowing, a dynamic reconfiguration is required. Partial shade has significantly decreased output power, which lowers PV panel’s efficiency. Numerous strategies have been put out to prevent power loss reduction when partial shade occurs. Existing techniques have not been able to provide better power extraction at extremely low irradiation. The proposed winnowing technique for dynamic reconfiguration is appropriate to get rid of power loss due to mismatch under very low radiation. The suggested approach enhances the output power under partially shade condition in low-irradiation. Fifteen different shading scenarios and six reconfiguration switching patterns were investigated to confirm the proposed concept. The proposed winnowing technique increases the solar PV array output power up to 59.3% by effectively decreasing mismatch losses in the solar PV system.

Mismatch loss analysis of solar array output power on stratospheric airship during flight

Stratospheric airships are long-endurance aerostats and have broad applications. All of the energy required for their operation is obtained from solar radiation, which makes accurate calculation of the energy output from the solar array crucial to the design and flight planning of the airships. However, the status of each photovoltaic module in the solar array may differ due to the airship curvature, resulting in mismatch losses and lowered output power, which has not been widely studied. In this paper, an irradiation model and a thermal model are established based on the actual arrangement of the modules. The output power model is established considering the non-uniform radiation in the array. The mismatch losses of the array are analyzed under different flight conditions. The output power of the solar array is decreased by up to 31.6% compared to the ideal state. Moreover, the proportion of mismatch losses increases with latitude, but the maximum mismatch loss power occurs at mid-latitudes. Then, an array reconfiguration method is proposed based on the irradiance dispersion index and position dispersion index. The reconfigured array increases output power by 11.5% and can maintain energy balance in continuous flight. The results can be used to correct the overestimation of the output power during the airship design or to guide the configuration of the solar array.

Voltage-Fed single stage inverter for generating systems with Multi-Input inverter using Pulse Width Modulation

A voltage-fed single-stage multiple-input inverter is developed for hybrid wind/photovoltaic energy generating systems. In this research proposes a revolutionary multi-input inverter that simplifies and reduces the power system's cost. Inverter comprises the DC-DC converters and full-bridge ac inverters, which are buck/buck-boost. This study proposed a multi-input converter for hybrid photovoltaic and wind energy systems, with the basis and enhanced functionalities created by the scholars included in the design. A Novel Predictive Current Control Algorithm (NPCCA) is proposed for Hybrid a renewable energy source which depends on improved space-vector Pulse-Width-Modulation (PWM) to provide high-quality current and quick dynamic reaction to incorporate changes. Also discussed are the solar array and wind turbine output power characteristics. The Maximum Power Point-Tracking (MPPT) methodology is accomplished using the perturbation and observation methods to resist all non-linearities in the typical I-V curves. The proposed multi-input converters results in lower production costs for the converters since they use fewer semiconductors and take up less space. Soft-starting and circuit safety features are added for real-world uses. The simulation outcome of the NPCCA framework attained in terms of accuracy is 92% and efficiency is 92% when compared with the other existing approaches.

Perovskite Solar Cells and Thermoelectric Generator Hybrid Array Feeding a Synchronous Reluctance Motor for an Efficient Water Pumping System

Nowadays, water pumping systems based on photovoltaics as a source of electricity have widely increased. System cost and efficiency still require enhancement in order to spread their application. Perovskite solar cells (PSCs) are the most hopeful third-generation photovoltaic for replacing the silicon-based photovoltaic thanks to their high power conversion efficiency, reaching 25.8%; tunable band-gap; long diffusion length; low fabrication temperature; and low cost. In this work, for the first time, we proposed a high-power-density hybrid perovskite solar cell thermoelectric generator (TEG) array for feeding a synchronous reluctance motor (SynRM) driving a water pump for use in an irrigation system. A control technique was used to achieve two functions. The first function was driving the motor to obtain the maximum torque/ampere. The second was harvesting the maximum perovskite solar cell array output power on the basis of the maximum power point tracking (MPPT) algorithm using the perturbation and observation approach. Thus, the proposed hybrid perovskite solar cell–thermoelectric generator feeds the motor via an inverter without DC–DC converters or batteries. Accordingly, the short life problems and the high replacement cost are avoided. The proposed complete system was simulated via the MATLAB package. Moreover, a complete laboratory infrastructure was constructed for testing the proposed high-power-density hybrid perovskite solar cell–TEG array for the water pumping system. The results revealed that using the high-power-density hybrid perovskite solar cell–TEG array, both the motor’s output power and the pump’s flow rate were improved by 11% and 14%, respectively, compared to only using the perovskite solar cell array. Finally, both the simulation and experimental results proved the high-performance efficiency of the system in addition to showing its system complexity and cost reduction.

MAXIMUM POWER TRACKING OF A SOLAR SYSTEM USING IMPROVED PARTICLE SWARM OPTIMIZATION ALGORITHM

For photovoltaic systems to be more efficient, maximum power point (MPP) tracking of the solar arrays is necessary. The output power of solar arrays is influenced by two factors: temperature and solar irradiation. It is also possible that a traditional MPP tracker would operate incorrectly because to the mismatch effect produced by partial shadow. There are many maximum values for the solar array power–current characteristics when it is partly shaded. For PV systems in partly shadowed conditions, this research provides an MPPT approach with enhanced particle swarm optimization algorithm.

Characteristic Study of Solar Photovoltaic Array Under Different Partial Shading Conditions

Photovoltaic (PV) systems are frequently exposed to partial or complete shading phenomena. Partial shading has a profound impact on the performance of solar power generation. The operational performance of PV arrays under partial shading shows multiple maximum power point peaks, therefore it is challenging to identify the actual maximum power point. This paper investigates the impact of partial shading location on the output power of solar photovoltaic arrays with various configurations. Multiple photovoltaic strings, in both parallel and series configurations, are considered. Different random shading patterns are considered and analyzed to determine which configuration has higher maximum power point. The sensitivity of the partial shading can change according to the partial shading types, shading pattern, and the configuration used to connect all PV modules. Moreover, the study also investigates the output of the PV array with shading two random models, two consecutive models, and three random and consecutive modules. Experimental results validate the analysis and demonstrate the effect of various partial shading on the eficiency and performance of the PV system.

An optimization approach for improving the solar array output power of stratospheric aerostat

Solar array is an integral part to the stratospheric aerostat energy system. The output power optimization of solar array needs to be conducted under the weight limitation for stratospheric aerostat long endurance mission. In the present paper, a rotatable system for optimizing the solar array output performance is proposed. Based on the theoretical model consisting of solar radiation model, energy model and optimization model, a MATLAB program is developed to calculate the thermal performance and output performance of solar array. The effects of latitude and flight date on the output performance are investigated in detail, the optimization results are obtained by comparing the rotatable solar array system with the traditional fixed solar array system. Studies have shown that the solar array output power is produced earlier with the rise of latitude and the output power peak value in summer solstice is greater than the values at other flight dates. The rotatable solar array system can comprehensively improve the solar array output power and the output power increment after optimization at high latitude is more than low latitude. The present work has valuable reference in solar array output power optimization and may be used to guide the design of the stratospheric aerostat energy system.

Layout optimization of stratospheric balloon solar array based on energy production

Solar array plays a decisive role in the energy system of stratospheric balloon. Optimizing the layout of solar array is beneficial to the improvement of energy production, but the research about this subject is rare. This paper established a theoretical model consisting of thermal and energy model, weight/lift equilibrium. A MATLAB computer program is developed to simulate the output power of solar array and the energy harvesting along with connection length and balloon diameter. Through comparative analysis, the theoretical model is proved to be feasible. Further, the effects of connection length, balloon diameter and the ratio of connection length to balloon diameter are discussed in detail. The results show that solar array total output power is sensitive to the variation of the connection length, balloon diameter and the ratio of connection length to balloon diameter. Moreover, the layout of solar array can be optimized though increasing the ratio of connection length to balloon diameter, however, the total output power would not increase when the ratio of connection length to balloon diameter is greater than 1.5. Therefore, Choosing the proper ratio of connection length to balloon diameter might be an effective approach for optimizing the stratospheric balloon energy system.

Propose a MPPT Algorithm Based on Thevenin Equivalent Circuit for Improving Photovoltaic System Operation

Various maximum power point tracking methods (MPPT) for photovoltaic (PV) power systems have been considered and developed to maximize the delivered possible power. The output power of PV cells with nonlinear characteristics is affected by temperature, solar irradiation and load. In this paper, a modelized photovoltaic source is proposed, based on the Thevenin equivalent circuit at the beginning. A ordinarily employed solar system model is linearized into simple Thevenin source-resistance representation. Next, a control algorithm associated with the relationship between controller’s PWM duty cycle of the MPPT boost converter and solar array output power, namely proposed MPPT algorithm, is introduced. This proposed method is compared with an existing popular MPPT algorithm to confirm its superior performance by using the MATLAB/SIMULINK simulation. Finally, a 50W DC-DC boost converter prototype is implemented and tested to verify the feasibility of the proposed control scheme.

Investigation on the effects of shadow on output performance and thermal characteristic of the solar array on stratospheric aerostat

The attenuation of solar direct radiation passing through stratospheric balloon has great impacts on solar array output performance and thermal characteristic. The thermal characteristic of solar array with balloon shadows taken into account is rare. In this study, we established a theoretical model which consists of solar radiation model, shadow model, thermal model and energy output power model to evaluate their power performance and thermal characteristic under shaded conditions. Based on the theoretical model, a MATLAB simulation program was developed. For model validation, solar array performances are simulated and compared with literature results. Comparing the results of calculation whether balloon shadow is considered or not, the balloon shadow greatly affects the output power and temperature of solar array. Effects of the date, latitude, rope length on the output performance and thermal characteristic of solar array were investigated in detail. The results show that the balloon shadow covering the solar array effectively reduces the direct solar radiation received by the solar array, which has contributed to the decline of the output power and average temperature of the solar array. In addition, it is found that choosing the appropriate rope length can effectively reduce the detrimental effects of the balloon shadow.

Optimization design of a thermal protection structure for the solar array of stratospheric airships

Abstract Renewable power system using solar array is one of the most critical subsystems for stratospheric airships. It is important of thermal protection for the stratospheric airship, because excessive temperature of solar cell may reduce its conversion efficiency and age the envelope material underlaid solar cells. Multi-objective optimization of a thermal protection structure with heat dissipation and insulation layers for solar array of a stratospheric airship is performed in this paper. The optimization process is carried out by a Nondominated Sorting Genetic Algorithm to decrease the sensitivity toward weights or demand levels. The specific temperature difference, which indicates the ratio of temperature reduction and structure density, and the output power of solar array are used to present the optimization aims. Three geometric variables related to the number of fins, width ratio of fins and thickness ratio of dissipation and insulation layer are selected as the design variables. Pareto optimal fronts representing the trade-offs between the performance parameters are obtained at last and optimization results are compared with previous studies and the thermal protection effects and output power of the solar array are both more excellent. Furthermore, the simulation of the thermal protection structure with optimization parameters are carried out at last.

Research on optimal solar array layout for near-space airship with thermal effect

The output performance of solar array on near-space airship can be effectively improved by the layout optimization of solar array. This paper studied the effect of layout parameters on output energy of solar array on the airship with and without thermal effect, and particularly the optimization of solar array layout under the thermal effect. Based on the thermal model of solar array and the layout optimization model, a Matlab numerical program is adopted to calculate the output power or energy of solar array and latitudes and the change trend of optimum layout parameters for whole year and different latitude. The theoretical model is clearly verified comparing with the experimental result of temperature distribution of solar array. The effect of layout parameter on the thermal performance of airship was then analyzed by CFD simulation. The results show that the output performance of solar array is significantly improved through optimized layout and the output power or energy is decreased when considering thermal effect. The optimization of layout parameter may increase average temperature of airship and the velocity of internal helium of airship. Therefore, it is valuable to investigate the thermal effect of solar array in practical engineering of solar power system.

A thermal model to investigate the power output of solar array for stratospheric balloons in real environment

It is very important to solve the energy problem of stratospheric balloon to operate at high altitude for extended durations. Solar energy is the ideal power choice for long endurance stratospheric balloon. This study outlines a simplified numerical model validated using field data covers the thermal model of solar array that is not affected by balloon inside environment as airship does, the solar radiation model, the power output model. The predicted and measured solar array temperature and output power values yield correspondence with deviations below 2.16%, 6.6%, respectively. Based on this numerical model, computer program has been developed and simulated. The simulation was applied to a stratospheric balloon flight in one of the cities of Turkey’s atmospheric conditions including real wind data. The output performance of solar array with and without thermal effect is reported. Furthermore, transmissivity of external encapsulation, wind speed on thermal performance and power output of solar array is discussed in detail. The results would be helpful for the design, operation of stratospheric balloon solar power system.

Renewable power system simulation and endurance analysis for stratospheric airships

Composition of renewable power system for stratospheric airships is introduced, curved paving model of solar array is established, the high accuracy calculation method for output power of solar array is proposed, and operation process of renewable power system is simulated. On basis of this, endurance of the stratospheric airship is evaluated, and the influence of some important factors on endurance is analyzed, including wind resistance strategy, photoelectric transformation efficiency of solar array and the specific energy of lithium battery. Simulation results show that, 1) endurance of the stratospheric airship can be improved by adjusting power sequential during day and night with maneuverable wind resistance strategy, for the case in this paper, endurance increases 24.2 h compared with fixed point wind resistance strategy, 2) endurance can be greatly improved in a certain range through increasing photoelectric transformation efficiency of solar array and the specific energy of lithium battery, for cases in this paper, endurance increases 73.5 h and 47.5 h respectively, 3) to realize closed cycle of renewable power system during day and night, attenuation of radiation flux with the change of date must be considered in design of renewable power system, and sufficient redundancy should be designed for solar array.

Simplified Analytical Model for Investigating the Output Power of Solar Array on Stratospheric Airship

Solar energy is the ideal power choice for long-endurance stratospheric airships. The output performance of solar array on stratospheric airship is affected by several major factors: flying latitude, flight date, airship’s attitude and the temperature of solar cell, but the research on the effect of these factors on output performance is rare. This paper establishes a new simplified analytical model with thermal effects to analyze the output performance of the solar array. This model consisting of the geometric model of stratospheric airship, solar radiation model and incident solar radiation model is developed using MATLAB computer program. Based on this model, the effects of the major factors on the output performance of the solar array are investigated expediently and easily. In the course of the research, the output power of solar array is calculated for five airship’s latitudes of 0°, 15°, 30°, 45° and 60°, four special dates and different attitudes of five pitch angles and four yaw angles. The effect of these factors on output performance is discussed in detail. The results are helpful for solving the energy problem of the long endurance airship and planning the airline.

Optimum area of solar array for stratospheric solar-powered airship

An optimization model of the optimum area of solar array for a stratospheric solar-powered airship is developed. The objective of the optimization is to reduce the mass of the solar array on an airship by keeping the equilibrium between output power and weight of solar array as a constraint. Based on several parameters of the typical existing airships, the optimization works are carried out to verify the effectiveness of the optimization model. Furthermore, the effects of the wind velocity, airship’s latitude and working date on the optimum area are analyzed in detail. The results of this study demonstrate that the optimization model is a good tool for the preliminary design of solar array on an airship. It can also be found that these influence factors have significant influences on the optimum area, and these factors should be considered together to obtain an optimum and balanced design due to the strong dependence on each other.

Output performance analyses of solar array on stratospheric airship with thermal effect

Output performance analyses of the solar array are very critical for solving the energy problem of a long endurance stratospheric airship, and the solar cell efficiency is very sensitive to temperature of the solar cell. But the research about output performance of solar array with thermal effect is rare. This paper outlines a numerical model including the thermal model of airship and solar cells, the incident solar radiation model on the solar array, and the power output model. Based on this numerical model, a MATLAB computer program is developed. In the course of the investigation, the comparisons of the simulation results with and without considering thermal effect are reported. Furthermore, effects of the transmissivity of external encapsulation layer of solar array and wind speed on the thermal performance and output power of solar array are discussed in detail. The results indicate that this method is helpful for planning energy management.

Modelling and Simulation of Solar PV Array Field Incorporated with Solar Irradiance and Temperature Variation to Estimate Output Power of Solar PV Field

Photovoltaic systems are designed to feed either to grid or direct consumption. Due to global concerns, significant growth is being observed in Grid connected solar PV Plants. Since the PV module generates DC power, inverter is needed to interface it with grid. The power generated by a solar PV module depends on surrounding such as irradiance and temperature. This paper presents modelling of solar PV arrays connected to grid-connected plant incorporated with irradiance and temperature variation, to design simulator to study and analyse effect on output power of solar PV arrays with irradiance and temperature variation, also to estimate the output power generated by PV arrays. The mathematical model is designed implemented separately on simulator for each PV components connected in PV systems, which are PV cell, Module, sting, array and field of arrays. The results from simulation based on model are verified by the data collected from power plants and experiments done on solar PV cell.