ANALYSIS OF PASSIVE FILTER COMPENSATING DEVICES AND THEIR EFFECT ON ELECTRICITY QUALITY INDICATORS

ABSTRACT This scientific work examines the key causes of power quality deterioration in modern distribution electrical networks, with particular attention given to the increasing proportion of consumers with nonlinear voltage-current characteristics. Such consumers, during their operation, generate non-sinusoidal current waveforms, which lead to the appearance of high-frequency harmonic components in the network and violate established power quality standards. Among these devices are switched-mode power supplies, adjustable speed drives for electric motors, arc steel-melting furnaces, electronic ballast units for fluorescent and LED lamps, as well as various types of converter equipment. Currents and voltages that contain a significant amount of harmonic content in their spectrum can be represented as a sum of sinusoidal signals with frequencies that are multiples of the fundamental frequency of the supply network (typically 50 Hz). The presence of these harmonics causes additional losses in transformers, overheating of cable lines, malfunctions of protective devices, false triggering of automation systems, and a general reduction in the reliability of the entire power system. To mitigate the negative effects of nonlinear loads on the quality of electrical energy, a set of organizational and technical measures must be implemented. These measures include providing separate power supply lines for powerful and active nonlinear loads, increasing the number of phases in rectifier circuits, and the use of passive, active, or hybrid filters, compensating devices, and matching transformers. The presented study emphasizes the necessity of a comprehensive approach to the analysis and reduction of harmonic distortions, and it proposes effective methods for improving power quality under the growing influence of nonlinear loads in industrial, commercial, and residential sectors of energy consumption.