Efficiency analysis of PV power plants shaded by MV overhead lines

Abstract

This paper deals with the occurrence of hot spot phenomena in photovoltaic (PV) systems under partial shading caused by objects on some parts of the modules. An interesting case of diffuse shadows is determined by overhead distribution lines whose path crosses or are in the proximity of the PV power plants. Investigating the impact of these shadows on reducing the power production of PV or on damaging the PV modules as the modules' temperature is increasing, is of high interest. At the SolarTech laboratory of Politecnico di Milano, the conditions for hot spot phenomena occurrence due to the overhead lines shading the PV cells were reproduced. Two experimental campaigns were carried out to investigate the currentvoltage and power-voltage characteristics, and the energy production. In each experimental campaign, the built shading structure was considered fixed and different shading conditions were created based on the natural displacement of the sun. The hot spot phenomena was revealed on a field PV installation in Italy, caused my medium voltage overhead lines shading the PV cells, using infrared imagery.

An Economic Analysis of the Shading Effects of Transmission Lines on Photovoltaic Power Plant Investment Decisions: A Case Study

“…Concerning Hungary, there are no research results available currently that are related to the investigations presented in this paper. Although some international research has touched upon certain aspects of the matter (e.g., Dolara et al, 2016 [ 29 ]; International Energy Agency, 2018 [ 17 ]; Chen et al, 2020 [ 14 ]), its complexity was not scrutinized. In addition, the results of the investigations herein can provide help with the formulation of the most suitable PV power plant construction strategies in Hungary and all around the world.…”

“…These diodes have their operating points, which have to be reached; otherwise, no electricity can be diverted, i.e., the cells will consume a part of the generated energy, creating [ 19 ] a hot spot phenomenon [ 20 ]. The electric characteristics related to the partial shading of PV modules have been treated in detail in several articles [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ], and it has been established that this phenomenon [ 29 ] leads to a higher rate of PV module failures and the accelerated aging of cells [ 11 ]. It is important, however, to mention that, at present, there is already a technological solution [ 20 ] that can efficiently handle the hot spot phenomenon [ 30 ] and the problems of loss by shading [ 31 ] in the case of crystalline PV modules [ 32 ].…”

An Evolutionary-Based MPPT Algorithm for Photovoltaic Systems under Dynamic Partial Shading

“…In a real world scenario, the shading process of a photovoltaic generator can be either deterministic or random. A deterministic partial shading process occurs in fixed PV installations; it is related to the motion of the sun in the sky and the fixed objects nearby to the PV generator [27], like trees, buildings, poles, etc., that can cause partial occlusion from the sun in some hours of the day. A deterministic partial shading process is usually a very slow process.…”

Hot Spot Analysis of Photovoltaic Module under Partial Shading Conditions by Using IR-Imaging Technology

“…A. Dolara et al (2016) [13] explained the hot spot phenomena which occurred in PV systems during the normal operation of modules under partial shading condition due to overhead line wires with a path crossing the PV filed. Small increase in temperature was recorded during the I-V curve measurement.…”