Currently, electric power companies and consumers pay great attention to improving the quality of generated and distributed electricity. The main goal is to produce clean electricity and distribute it to end users with acceptable electricity quality characteristics in a cost — effective manner. Currently, the importance of electricity quality aspects has increased due to the rapid development of power electronic devices and renewable energy sources under the auspices of smart grids. In addition, the deregulation of the electricity market has led to the emergence of a competitive market in which numerous utility companies are trying to supply the best products (generated electricity) to customers by supplying them with the highest quality electricity. As a result, the quality of electricity will play a significant role in modern electric power systems. However, there are also difficulties before it becomes possible to apply the limits of electricity quality indicators more widely. One of the difficulties is that there is currently no single generally accepted definition of electricity quality due to the different perspectives and phenomena of electricity quality. In addition, the quality of electricity has different interpretations for people in different electrical organizations. Some define the quality of electricity as the quality of voltage, others as the quality of current, and some practice the quality of electricity as the reliability of the system.

Metal-enclosed isolated-phase bus systems are widely used for the electrical connection of generators with step-up unit transformers and auxiliary transformers of power plants. An increase in the capacity of generators and step-up unit transformers requires an increase in the rated current and voltage of bus systems. Operation with high currents leads to heating of the elements of the current line. Also, an increase in operating currents results in an increase in shock currents in the short-circuit mode, leading to an increase in mechanical stress on the structural elements of the power line. In this regard, it also becomes relevant to conduct tests for heating with rated current and tests for resistance to short circuits of phase-shielded current lines. To calculate short-circuit currents and select the parameters of the test equipment, it is necessary to know the reactance and impedance of the current line, which depend on its design and can be determined by measurements and calculations. The paper provides information about the design features of metal-enclosed isolated-phase bus. An analysis of the data on the impedance of bus system was carried out. The results of calculations using analytical formulas and using the finite element method are presented, and a method for measuring the impedance of a bus system is described. It is shown that the impedance of the bus system can be significantly less than the impedance of the busbars for connection to the test installation.

This paper presents an automated electric drive with an original frequency converter design, in which a transistor switch and a freewheeling diode are additionally introduced into the DC link, allowing for regulation of the voltage and power supplied to the voltage inverter input. The paper presents the results of computer modeling of the proposed automated electric drive system, adapted for use in fuel and energy complex facilities.