The article presents and discusses the results of analysis and experimental studies of the metrological characteristics of Rogowski coils made in HDI PCB (High Density Interconnect Printed Circuit Boards) technology. The purpose of the research and analysis was to determine the possibility of their use in the metering units of automated electrical power systems. Particular emphasis placed on the formation of the resonant characteristics as well as to provide suitable resistance to external interfering electromagnetic fields. This allows, inter alia, the use of Rogowski coils for detection of interfering transmissions PLC high-frequency conductive currents. Basing on the obtained results, conclusions and recommendations for practice are formulated.

Knowledge of the conducted emissions in the frequency range 2–150 kHz contains some gaps related to the impact of the harmonics in the supply voltage on the nature of these emissions. It can be noticed that the conducted emissions from non-sinusoidal power supplies have not been studied sufficiently, and that the impact of this distortion may be greater than the generally known results of emission tests carried out under standardized test conditions. This paper is aimed at investigating experimental cases of the influence of supply voltage waveform distortion on non-intentional emission in the range 2–150 kHz and the efficiency of power line communication based on selected PRIME (PoweRline Intelligent Metering Evolution) power line communication (PLC) technology. A series of experimental laboratory studies were investigated, representing the operation of the investigated PLC system with different types of end-user equipment (LED—Light Emitting Diode, CFL—Compact Fluorescent Lamp, induction motor with frequency converter) working under a distorted supply voltage condition obtained by the programmable power supply for different scenarios of the admissible harmonics contribution in the range 0–2 kHz. The scenarios included limits defined in standards EN 50160 and IEC 61000-4-13. The researchers used spectral analysis with a notation to emission limits, compatibility levels, and mains signalling, as well as statistics of the PLC communication. The obtained results provide important conclusions, which may be applied both in the development of the design of the appliances in question and the higher frequency emission testing methods.

This paper presents and discusses results of analysis from investigations of arc-to-glow transformation phenomenon at contact opening, under dc low-energy (≤10 J) and low-voltage (≤250 V) inductive loads. Dependence of the duration of arcing and glowing on current magnitude, voltage magnitude, properties of the contact material, gas quenching medium velocity and its pressure, as well as contact opening velocity and contact gap are investigated. The transition phenomenon of arc-to-glow is analyzed by means of fast photography and emission spectroscopy. Also discussed is the theoretical evaluation of conditions of arc instability. From the results, possible procedures are formulated to control the arc-to-glow transformation for practical use in dc low-voltage and low-power electrical grids.

The paper discusses the possibility of obtaining the required parameters of Rogowski coils when apply of printed circuit board high density technology. Selected results of investigations are presented and examples of Rogowski coils for use in electrical power system protections are given.

Application of a high-efficiency voice communication systems based on broadband over power line-power line communication (BPL-PLC) technology in medium voltage networks, including hazardous areas (like the oil and mining industry), as a redundant mean of wired communication (apart from traditional fiber optics and electrical wires) can be beneficial. Due to the possibility of utilizing existing electrical infrastructure, it can significantly reduce deployment costs. Additionally, it can be applied under difficult conditions, thanks to battery-powered devices. During an emergency situation (e.g., after coal dust explosion), the medium voltage cables are resistant to mechanical damage, providing a potentially life-saving communication link between the supervisor, rescue team, paramedics, and the trapped personnel. The assessment of such a system requires a comprehensive and accurate examination, including a number of factors. Therefore, various models were tested, considering: different transmission paths and types of coupling (inductive and capacitive), as well as various lengths of transmitted data packets. Next, a subjective quality evaluation study was carried out, considering speech signals from a number of languages (English, German, and Polish). Based on the obtained results, including both simulations and measurements, appropriate practical conclusions were formulated. Results confirmed the applicability of BPL-PLC technology as an efficient voice communication system for the oil and mining industry.

The article presents the structure, principle of operation and measurement properties of the developed control system intended for e-management of detection and measurement of disturbances in the low-frequency bandwidth of the PLC (3 kHz-148 kHz). As a detector, Rogowski’s coil made in high-density printed technology (PCB HDI) was used. The results of testing the parameters of both particular components and the completed system in transient as well as in steady state are presented. Based on the obtained measurement results, appropriate practical conclusions are formulated.