Partial shading conditions of photovoltaic (PV) modules often occurs in urban areas leading to losses in electricity power generation of the PV power plant. The purpose of this study is to present how the PV power plant with high value of inverter power sizing factor (K_inv) can achieve high performance and power production under partial shading conditions with high shading losses. In this paper the results of long-term monitoring, performance analysis and experimental results are presented, while the results are compared to the estimated values calculated using PVsyst software. The study focused on the PV power plant at the Faculty of Technical Sciences (FTS) in Novi Sad, Republic of Serbia, for the period between the years 2012 and 2019. It has been shown that the values of PV power plant performance parameters are better than expected (very high), and resemble the power plants operating without shading. The high value of the inverter power sizing factor may lead to occasional saturation of the inverter when certain conditions are met, but most of the times it allows the inverter to operate at a more optimal power level. PV module soiling and power degradation is within the limits mentioned in the literature. The increase in K_inv in the partial shading conditions favorably affects the performance, does not degrade the efficiency of the inverter at saturation, reduces the effect of soiling and aging of PV modules, leading to higher power production.

The amendment of the Law on Energy and the adoption of the new Law on Renewable Energy Sources enabled a sudden increase in the installed capacity of photovoltaic (PV) power plants in the Republic of Serbia in 2022. Thanks to the new modality called prosumers, interest in the construction of PV power plants has increased, both with households and with commercial entities. The general situation in the world, crises, pandemics and wars have caused a drastic increase in the price of energy products, and therefore electricity. To contribute to the reduction of the negative impact of climate change, it is an ideal opportunity to use the production of electricity from one's own power plant to compensate for an increased cost of energy. The most affordable and simplest is the construction of the PV power plant because solar energy reaches every roof. This paper describes the possibilities of building PV power plants in the status of prosumers from the technical and legal aspects. In addition to examples from practice, the current state of installed capacities of PV power plants in the Republic of Serbia in the status of prosumers is given.

This paper examines the control strategy adopted for six-phase machines that have been designed as double three-phase machines without a displacement between the magnetic axes of the two sets of three-phase windings (6PH-ZS). The approach is based on vector control principles, enabling the independent control of direct- and quadrature-current components in both three-phase windings. The advantages of such an approach stem from the flexibility of the current distribution between windings, which aims to achieve the required flux and torque. The proposed control strategy is considered for both motor and generator operating regimes. However, an additional quasi-transformer regime is also addressed. While the classic operation regime requires the machine to produce either driving or generating/braking torque, the quasi-transformer regime enables the control of electric power flow between two three-phase windings. A theoretical analysis of the machine model and control algorithm for the flow of electric power through machines is presented for the three aforementioned operating regimes. Verification of the proposed control algorithm is performed through extensive experimental verification.

The rapid growth of urban freight transport and e-commerce has significantly increased the demand for environmentally friendly last-mile delivery solutions. This study proposes a strategic MCDM framework for selecting the most suitable charging infrastructure configuration for electric delivery vehicles. The approach combines the extended FullEX method for criteria weighting and the Additive Ratio Assessment (ARAS) method for ranking alternative charging strategies. Three alternatives are considered: depot/logistics charging, urban public charging, and transport hub charging. The evaluation is based on six criteria grouped into economic, technical, logistical, and environmental–social categories. To ensure the reliability and consistency of the analysis, expert opinions and findings from the literature are incorporated into the evaluation process. The proposed framework provides practical decision support for urban planners and logistics operators seeking to develop efficient, sustainable, and well-balanced charging infrastructure for electric delivery vehicles.