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Study of Voltage Stability Due to Shading Effects on Photovoltaic Penetration in PKMT Distribution System
摘要： PV output power is firmly influenced by temperature and solar irradiation that fall on the surface of the PV modules. Shading which cross-wising the surface of PV modules is major factor that prevails the degradation of its performance. The shading in PV arrays is caused by the presence of cloud, dust, fog, trees, the shadow near buildings, and so on. As the result of the shading effect, the voltage and current outputs fluctuate which would in turn reducing the efficiency of the PV output. The voltage and current of PV solar cells will drop from partial shading effect experiment which consists of 20%, 40%, 60%, 80%, and 100% shading area. This paper shows the effect of PV system over the voltage stability by variating the shading conditions using simulation by ETAP software 12.6.0.
关键词： Voltage Stability,Photovoltaic,Shading Effects,ETAP software
更新于2025-09-16 10:30:52
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Disturbance Characteristics of the Off-Grid Photovoltaic System in the Frequency Range from 9 - 150 kHz with Changing Solar Irradiance and Shading Area
摘要： A solar power plant converts light into electricity using photovoltaics. It uses an inverter to convert DC to AC current to be connected to an AC load. Increasing use of solar panels in household application results in an increase in the use of inverters, in which some might due to the fact that inverters can produce disturbances at a frequency between 9-150 kHz. This study is focused on observing the disturbance characteristics of an off-grid photovoltaic system due to variations of irradiation and shading in the frequency range from 9 - 150 kHz. It is expected that the output of this observation can provide a reference for research in determining the effects on electric power system. This observation provided a shading effect of 0%, 25%, 50%, 75%, and 100% of the photovoltaic area and then conducted observation based on two solar irradiation conditions. Based on the observations, it is identified that in general there are 3 frequency ranges of dominant disturbances, they are: 20-25 kHz, 72-73 kHz, and 144-146 kHz. Their voltage disturbance will decrease with increasing shading area, where at shading conditions of 25% and 50% they will have a value voltage disturbance that tends to be the same as that in the 3 dominant frequency ranges.
关键词： disturbance characteristics,off-grid,shading area,photovoltaic system,solar irradiance
更新于2025-09-16 10:30:52
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Power rating analysis and protection for photovoltaic-isolated port based differential power processing systems
摘要： In a photovoltaic generation system (PGS), photovoltaic (PV) modules are often connected in series for increased string voltage. However, a significant reduction in the actual output power is observed due to the manufacturing tolerance, module aging and partial shaded. Compared with conventional methods such as bypass diodes and PV module reconfiguration, modular distributed architecture especially the differential power processing (DPP) is able to yield high output power even under partial shading conditions. Moreover, the system efficiency is improved since only the differential power is processed by the DPP converters. This paper mainly focuses on the power rating analysis and protection of PV-isolated Port (PV-IP) based DPP systems considering the significant power stress difference among DPP converters under different partial shading conditions. The voltage equalization (VE) control used in this work is able to provide up to 77% efficiency improvement through the simulation evaluation. The protection algorithm is proposed for the PV-IP DPP architecture to improve the system reliability even when some DPP converters are found failed. With the proposed protection strategy, not only the high output power yield can be maintained, but also the modular design of DPP converters with smaller power capacity can be achieved. Simulation and indoor experimental tests under various partial shading conditions were carried out to validate the effectiveness of the proposed power rating analysis and protection scheme.
关键词： Partial shading,Differential power processing (DPP),Power rating,PV submodule integrated converter (subMIC),Optimization,PV-Isolated Port (PV-IP) DPP
更新于2025-09-16 10:30:52
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Effect of adjacent shading on the energy and environmental performance of photovoltaic glazing system in building application
摘要： Photovoltaic (PV) system is a commonly adopted renewable energy system in building application. In most of the assessments on PV system, there is no consideration on adjacent shading effect cast by surrounding buildings which may lead to over-estimation of PV energy generation and inaccurate calculation of energy payback time (EPBT). This paper investigates the effect of adjacent shading on energy generation and EPBT of PV system. A survey had been conducted to identify and select 25 existing commercial buildings with different degrees of adjacent shading (expressed in terms of sky view factors (SVF), ranging from 0.16 to 0.95) and orientations. Through computer simulations using EnergyPlus, it reveals the significance of adjacent shading effect on the PV energy generation as well as EPBT of building-integrated PV glazing system for the 25 selected buildings, in terms of two ratios, namely PV electricity energy ratio (0.18e0.84) and energy payback time ratio (1.17e5.74). Moreover, a correlation between SVF and PV electricity energy ratio was established (PVEE Ratio ? 0.3867 SVF2 t 0.4176 SVF t 0.0975) with which building professionals can evaluate the PV energy generated and EPBT of a building-integrated PV glazing system in building application, under adjacent shading effect.
关键词： Adjacent shading effect,Sky view factor,Photovoltaic system in building application,Embodied energy in photovoltaic system,Energy payback time
更新于2025-09-16 10:30:52
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Fractional Chaos Maps with Flower Pollination Algorithm for Partial Shading Mitigation of Photovoltaic Systems
摘要： Solar Photovoltaic (PV) systems have become prominent and have attained the attention of energy engineers, governments and researchers. To achieve the maximum bene?t from the PV system in spite of its nonlinear characteristic and environmental conditions, ?nding a robust maximum power point tracking method is essential. Over two decades, various researchers proposed numerous MPPT methods, but they failed to evaluate their methods on consistency, reliability, and robustness over several numbers of runs. Most of the researchers examined one con?guration and they did not to consider the dynamic change in the irradiation conditions. Therefore, in this manuscript, the authors introduced a novel optimization technique Fractional chaotic Flower Pollination Algorithm (FC-FPA), by merging fractional chaos maps with ?ower pollination algorithm (FPA). The proposed technique, help FPA in extracting the Global Maximum Power Point (GMPP) under different partial shading patterns including with different PV array con?gurations. The proposed FC-FPA technique is tested and evaluated over 5 different patterns of partial shading conditions. The ?rst three patterns are tested over 4S con?guration made with Shell S36 PV module. The other two patterns are applied to the 4S2P con?guration of Shell SM55 PV panels. The performance of the proposed variant is investigated by tracking the GMPP for abruptly changing shade pattern. Exclusive statistical analysis is performed over several numbers of runs. Comparison with perturb and observe MPPT technique is established. These results con?rm that, the proposed method shows fast convergence, zero oscillation and rapid response for the dynamic change in irradiation with consistent behavior.
关键词： maximum power point tracker,?ower pollination algorithm,fractional chaos maps,partial shading conditions
更新于2025-09-16 10:30:52
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Determination of economically optimised building integrated photovoltaic systems for utilisation on facades in the tropical climate: A case study of Colombo, Sri Lanka
摘要： Building integrated photovoltaics (BIPV) are becoming a viable solution for clean on-site energy production and utilisation to combat the existing energy crisis. In tropical climates, although rooftops are ideal for photovoltaic (PV) module integration, the available area may be insufficient to meet building energy demand due to the recent high-rise nature of urban buildings, causing a requirement for the utilisation of facades. However, the high angle of solar elevation means that facades are unfavourably oriented towards receiving incident solar irradiation. In addition, the issue exists of high solar heat gains into built spaces. This paper proposes a method to utilise horizontally inclined photovoltaic modules integrated on solar shading devices in order to combat these issues of unfavourable inclination and solar heat gains in commercial office buildings in Colombo, Sri Lanka. Various strategies are introduced and evaluated in terms of their inclination angles and the distance between installations. The results are analysed in terms of economic potential in order to determine which strategies are capable of producing the most electricity and reducing building cooling loads for the lowest installation costs. The results show that horizontal inclinations of PV on facades are capable of generating nearly 8% more electricity as a percentage of the building energy consumption when compared with traditional vertical PV facade installations.
关键词： facades,office building,photovoltaic integrated shading systems,building integrated photovoltaics,optimisation
更新于2025-09-16 10:30:52
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Impact of Bypass Diode Forward Voltage on Maximum Power of a Photovoltaic System under Partial Shading Conditions
摘要： The maximum power of a photovoltaic system can reduce significantly under partial shading conditions. Bypass diodes can be used in photovoltaic systems to bypass the shaded photovoltaic modules during partial shading. The bypass diode possesses a forward voltage that introduces a voltage drop in the photovoltaic system upon activation. Therefore, the maximum power of a photovoltaic system can reduce further during partial shading due to the forward voltage of the bypass diode. This paper presents an investigation into the effect of bypass diode forward voltage on the maximum power of a photovoltaic system under partial shading conditions. The results indicated that the forward voltage of the bypass diode did not necessarily decrease the maximum power of the photovoltaic system. This depends on whether the maximum power is delivered at a lower or higher voltage. When the maximum power is delivered at a higher voltage, it is insusceptible to the forward voltage. Conversely, when the maximum power is delivered at a lower voltage, it is susceptible to the forward voltage. In the worst-case scenario, the forward voltage of the bypass diode reduced the maximum power of the photovoltaic system by 16.48%, which was already subject to partial shading loss.
关键词： P-V characteristics,solar energy,Photovoltaic,bypass diode,partial shading
更新于2025-09-12 10:27:22
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[IEEE 2019 International Conference on Power Generation Systems and Renewable Energy Technologies (PGSRET) - Istanbul, Turkey (2019.8.26-2019.8.27)] 2019 International Conference on Power Generation Systems and Renewable Energy Technologies (PGSRET) - Modeling Photovoltaic String in PLECS Under Partial Shading
摘要： The industry of solar energy and its application areas have developed and received much attention over the last two decades. Therefore, the types of photovoltaic (PV) system simulations are investigated and mostly discussed models close to the physical behaviour of a PV panel or system. Under the real conditions such as cloud coverage, the shadows of nearby objects, dusty air, and dirty surface area, etc. result in partial shading issue, which is the core problem of predicting how the system behaves electrically. This paper describes the electrical behaviour model of an established PV string consisting of an experimental curve of CHN250-60P panel shown in the datasheet. The simulation model is performed through the instrumentality of Piecewise Linear Electrical Simulation (PLECS) Block-set in MATLAB/Simulink platform. With the proposed model, the I-V and P-V curves of the system can be represented according to the values of a 3D Lookup Table (LUT). Consequently, the simulation results are dealt with partial shading issue to verify a correct model in different solar irradiance and temperature.
关键词： modeling,Photovoltaic systems,PLECS?,MATLAB,partial shading
更新于2025-09-12 10:27:22
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A capacitor based fast I-V characteristics tester for photovoltaic arrays
摘要： In order to efficiently evaluate the operating status of photovoltaic (PV) arrays, a design of fast current-voltage (I-V) characteristic tester is proposed in this paper. The tester uses the dynamic capacitor charging method to quickly sweep I-V characteristic curves. Then, a new artificial bee colony and Nelder-Mead simplex (ABC-NMS) hybrid algorithm is used to extract parameters of the single diode model of PV arrays. The experimental results show that the tester can quickly measure high-quality I-V curves of PV array and achieve accurate model parameters extraction. In addition, the root mean square error (RMSE) of curve fitting can be used to effectively indicate the partial shading condition.
关键词： I-V characteristics testing,ABC-NMS algorithm,dynamic capacitor charging,PV arrays,parameter extraction,partial shading
更新于2025-09-12 10:27:22
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Effect of partial shading patterns and degrees of shading on Total Cross-Tied (TCT) photovoltaic array configuration
摘要： Effect of partial shading on PV modules is simulated. Three standard configurations of PV array consisting of series-parallel (SP), bridge-linked (BL), and total cross-tied (TCT) are studied. Nine PV panels are arranged in 3x3 array. The suitable solar radiation level to start reconfiguring the PV array according to shading pattern is investigated. Partial shading of 1, 2 and 4 panels in 9 are simulated. From the simulation results, it is found that the reconfiguration of PV arrays may not increase the power output higher than 5% when there are shaded greater than 50% of the total area. Therefore, it is unnecessary to reconfigure the PV array. Conversely, if shaded area is less than 50% reconfiguring can improve the power output. Moreover, different shading patterns provide different power outputs even if the shaded areas are equal and the points to start reconfiguring the array are different for various shading patterns.
关键词： bridge-linked,partial shading.,Solar reconfiguration,total cross-tied
更新于2025-09-12 10:27:22