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The atmospheric electric current, "air–earth current", flows between the low ionosphere and Earth's surface. The source of this current is the potential difference between the global equalizing layer called the ionosphere and the ground surface. According to Wilson's concept of the Earth's Global Electric Circuit, in the areas of so-called fair weather, based on current measurements at the Earth's surface, it is possible to conclude the global electrical processes in the ionosphere and higher layers. The theoretical basis for this inference is the law of continuity of electric current or the principle of conservation of electric charge. We present the results of simulations of the distribution of electric field lines for sensors with different geometries placed in a uniform electric field, representing the atmospheric electric field. The sensors are metal surfaces on which electric charges are induced or deposited. In the external measuring circuit to which the sensor is connected, an electric current [A] will flow, related to the air–earth current density [A/m2], but their relationship may be challenging to interpret. We analyze the impact of sensor geometry on the possibility of interpreting the atmospheric electric conduction and atmospheric displacement current based on the current measured in the external circuit. This present method can be used for the geometric construction of new sensors at the stage of determining the electrical characteristics of the sensor (e.g., effective collecting area). It can support the comprehensive design of a measurement system at the interface between an atmosphere, sensor, and electronic equipment. [ABSTRACT FROM AUTHOR]

Photovoltaic power plants are gaining in popularity and availability every year, resulting in a massive increase in their number and size. However, each such investment involves allocating large land areas, the cost of which may be high. For this reason, there has been an increasing interest in the use of post-industrial wastelands in the form of artificial water reservoirs which often occupy large areas. Because their use as places of recreation can be dangerous for people, it is a cheap alternative for the foundation of a floating photovoltaic power plant. In addition, it has an advantage over the land version in that it is possible to produce a more significant amount of energy by using the sun's rays reflected from the water's surface. Despite these undeniable advantages, such a structure poses several technological challenges. This article focuses on the aspect of lightning protection, which is particularly important due to the structure's location in the open, and also a specific ground type with noticeably different mechanical and electrical characteristics than typical soil. Aspects such as the lightning hazard, arrangement of lightning rods, down conductors, lightning equipotential bonding, and various earthing configurations are discussed. The presented analysis is based on geometric models and simulations made in the Ansys/Maxwell 3D environment and is supplemented with calculations in Matlab/Simulink. [ABSTRACT FROM AUTHOR]

The aim of the considerations presented in the article was a stand-alone ground-based photovoltaic power plant. The article is devoted to the qualitative analysis of some lightning protection configurations. These types of constructions often require an individual look at the design and execution of lightning protection installations, which causes problems with the selection of optimal solutions. These problems relate primarily to the way the lightning rods are arranged to create protection zones, but also to the way they are attached: to the supporting structure for PV modules or as free-standing. Another problem raised in the article is the way how lightning current is discharged from rods to the ground and how it is dispersed there. Due to the vast area of such facilities and the requirements for electrical safety, it is necessary to consider and design a ground system with optimal electrical parameters, but also technical and economic ones. All these elements have their impact on the value of voltages induced in the electrical installation, which is also presented in the content of the article as the magnetic field distribution and calculation of induced voltages in an exemplary configuration. Finally, this article will compare described technical solutions encountered in selecting the best protection method for this type of photovoltaic installation. [ABSTRACT FROM AUTHOR]

This paper presents the possibilities of reducing emergency situations and reducing the time of failure in the power grid. The paper contains a detailed description of the method (algorithm) of operation in emergency situations on the example of a Gas-Insulated Switchgear (GIS) located in one of the system-forming (node) stations in the power grid. The level of detail contained in this paper, which has not been previously encountered in previous publications, favors an in-depth understanding of the possible solutions that result from these emergencies. The above method (algorithm) of activities has been developed based on three levels of research: simulation, theoretical and practical. This means that the simulation analysis that was performed based on theoretical information was experimentally tested as part of an emergency situation in one of the system-forming (nodal) stations in the power system. In order to achieve the result described in this article, one of the most promising types of devices used in power systems was selected - the GIS. This has been confirmed by numerous analyzes of the effectiveness of these devices included in this article. The paper contains a detailed description of the individual steps in the field of corrective actions and aimed at minimizing downtime. In addition, this article provides guidance to monitor possible emergencies that are designed to increase the reliability of the power grid. [ABSTRACT FROM AUTHOR]