Improvement of Shade Resilience in Photovoltaic Modules Using Buck Converters in a Smart Module Architecture

Abstract

Partial shading has a nonlinear effect on the performance of photovoltaic (PV) modules. Different methods of optimizing energy harvesting under partial shading conditions have been suggested to mitigate this issue. In this paper, a smart PV module architecture is proposed for improvement of shade resilience in a PV module consisting of 60 silicon solar cells, which compensates the current drops caused by partial shading. The architecture consists of groups of series-connected solar cells in parallel to a DC-DC buck converter. The number of cell groups is optimized with respect to cell and converter specifications using a least-squares support vector machine method. A generic model is developed to simulate the behavior of the smart architecture under different shading patterns, using high time resolution irradiance data. In this research the shading patterns are a combination of random and pole shadows. To investigate the shade resilience, results for the smart architecture are compared with an ideal module, and also ordinary series and parallel connected architectures. Although the annual yield for the smart architecture is 79.5% of the yield of an ideal module, we show that the smart architecture outperforms a standard series connected module by 47%, and a parallel architecture by 13.4%.

Photovoltaic System Design and Performance

“…The method was developed to improve the detection of shaded PV systems, and it was experimentally validated. In order to mitigate shadow-induced losses in PV modules, Mirbagheri Golroodbari et al [11] developed a smart PV module architecture consisting of 60 silicon solar cells. This module optimally consists of ten groups of six series-connected solar cells in parallel to a DC−DC buck converter.…”

PV System Design and Flight Efficiency Considerations for Fixed-Wing Radio-Controlled Aircraft—A Case Study

“…It is the author's opinion that modern fault diagnosis via thermal imaging or electrical measurements could be used in order to avoid take-off of faulty UAVs [42]. However, it is expected that flexible solar modules have high reliability and certain resistibility on impact [28]. UAVs are exposed to frequent vibrations during landing and in the air, so there is the possibility of mechanical failure on the UAV.…”

“…Tests were repeated three times at the aforementioned locations and results coincide with measurements taken earlier at other locations (e.g., Viškovo, near Rijeka, Croatia-also 300 m above sea level). For a larger planes (wingspan > 2 m), multiple power converters could be used in order to improve the resilience of the UAV PV system in regards to the shade problem [28,41,43]; otherwise, photovoltaic converters could add additional weight which UAVs cannot sustain during longer flights.…”

“…It was taken that PV panels could generate 15 W. This statement could be sustained by the calculation involving solar radiation of 1100 W/m 2 , solar cell efficiency η of 23% and dimensions of solar panel of 0.2 m·0.3 m (S = 0.06 m 2 ). By multiplying these values [28], an electrical power of 15 W could be obtained: P = P S ·S·η = 1100 × 0.06 × 0.23 = 15.18 W.…”

“…In this paper results are obtained by changing the limited number of parameters of fixed-wing UAV as in a recent publication [26].Concerning the solar radiation in kW/m 2 , different data obtained for different areas of the world could be found in the literature. Solar radiation measured in the United Kingdom (UK) is quite low, with maximum values of daily solar radiation below 1 kW/m 2 [27][28][29]; furthermore, frequent cloud appearance results in intervals with solar radiation below 500 W/m 2 . On the other hand, in India and Australia, a solar radiation of 135 kW/m 2 is used frequently in calculations.…”