Electricity

Physical and Monetary Electricity Intensity (End User Expenditures in GDP Fractions). Electricity Prices in Russia, the United States and Other Countries

2025-08-08T07:54:25+00:00

The article analyzes interrelation between the gross domestic product (GDP) and electricity consumption in the economy of different countries. It is noted that the level of electricity consumption in a country in a particular year is determined by the GDP physical and monetary intensity. The GDP physical electrical intensity is defined as the ratio of net electricity consumption to the GDP volume. According to the economic theory, in performing international comparison, a GDP should be calculated in dollars according to purchasing power parity over the entire GDP basket ($PPP). The GDP monetary electricity intensity in a particular year is defined as the expenditures of electricity end users taking into account all taxes in GDP fractions. It is shown that among large and largest countries around the world, Russia in 2023 was in the 12th place in terms of physical electrical intensity and was close to the United States, and in monetary terms it was in the 27th place out of 48 large countries with populations of more than 9 million people, with developing or developed economies. The ratio of the GDP monetary to physical electrical intensity is equal to the price (expenditures of end users) for 1 kWh of electricity in $PPP. Accordingly, when comparing electricity prices internationally in different countries, they should be recalculated for $PPP. In 2023, the price for electricity in Russia was 1.6 times higher than it was in the United States, and significantly higher than that in the hydrocarbons and coal exporting countries, as well as in the largest industrial countries (China, South Korea, etc.).

Calculating the Number of Lightning Induced Outages of a Double-Circuit 110 kV Overhead Power Line

2025-08-08T08:00:26+00:00

The voltage surges in a double-circuit 110 kV overhead power line are analyzed using the methods of grounding theory, and the probability of insulation back flashovers is quantified using the dangerous currents method. The article proposes a new approach to the choice of calculated lightning strike points – in the overhead ground wire at a distance of a quarter of a span. In the frequency-dependent high-resistance soil model recommended by the CIGRE standard, the grounding conductor pulse impedance is less than the stationary one, therefore, voltage surge levels at the pulse front decrease, and insulation back flashovers occur during pulse decay. The expected number of lightning outages of a 110 kV double-circuit overhead power line does not exceed the average operating values with a grounding rods resistance of up to 15 Ω. A typical four-leg grounding device (with legs up to 60 m) satisfies the specified resistance in the soil with a resistivity of up to 1500 Ω·m. If its resistivity is higher, it is recommended to strengthen the tower grounding systems with a counterpoise grounding device, hang a second overhead ground wire under the overhead power line wires, or lay it on the ground surface. Means for protection against double–circuit overhead power line outages, namely, increasing the number of insulators in one circuit and installation of line surge arresters, are studied.

Development of a Device for Diagnosing Unbalanced Short Circuits in 10 kV Overhead Power Lines

2025-08-08T08:11:02+00:00

The article addresses the development, based on the Arduino platform, of an intelligent microprocessor device intended to determine the type and place of an unbalanced short circuit fault in 10 kV overhead power lines. The device analyzes phase currents and voltages, as well as their zero and negative sequence components. An algorithm based on a pre-trained neural network of the multilayer perceptron type (MLP) has been implemented, which is capable of classifying, in real time, 12 different types of short circuit faults, including single-phase, two-phase and three-phase short circuits, as well as ground faults. The neural network was trained, based on the data obtained, in the MATLAB/Simulink environment, followed by integrating the algorithm into the Arduino environment. Laboratory tests of the mock-up with simulation of emergency modes have confirmed high accuracy (more than 95%), high response speed (the response time is less than 80 ms), and stability of the device performance. The hardware solution features compactness, low power consumption, simple configuration, and the ability to visualize the result. The proposed device can be effectively integrated into local relay protection and monitoring systems. Its application is especially relevant in 6-10 kV distribution networks under the conditions of limited financing, remoteness of facilities and the need to improve the power supply reliability.

Reactive Power Compensation under the Conditions of Distorted Currents and Voltages

2025-08-08T08:19:48+00:00

Matters concerned with improving the energy efficiency of modern industrial enterprises are addressed. The article presents the results of an instrument-assisted analysis aimed at studying the performance of power supply systems of industrial enterprises in the agricultural sector with an installed capacity of 7–15 MV•A containing their own generation facilities. Such enterprises are characterized by high reactive power absorption and the presence of spontaneous higher harmonic current components caused by the availability of nonlinear loads. Such conditions result in a high failure rate of reactive power compensation (RPС) devices. Despite the satisfactory total harmonic distortion coefficient (THD) for voltage, which does not exceed 5.5 %, the THD for current reaches 70 % or more. The cumulative effect from such operating conditions is the development of an emergency mode in the power supply system. The article considers methods for solving the problems of current and voltage waveform distortion and stabilizing the electric power quality in the presence of RPC devices. The electromagnetic transients that occur during the operation of combined reactive power compensation and harmonic filtering devices are simulated for a power supply system fragment. On the simulated oscillograns of currents, voltages, active and reactive power, the article has demonstrated the effects on decreasing the waveform distortion level and how the RPC devices operate at their connection point given a determinate level of the harmonic spectrum and the operation of several passive filters.

Analytical Characteristics of a Synchronous Generator

2025-08-08T08:31:20+00:00

The basic characteristics of synchronous electric machines are conventionally constructed based on the results of experimental studies. Methods for constructing them based on the results of analytical calculations are not given in the known literature. Therefore, it is difficult to assess the extent to which the analytical design calculation results comply with the requirements specification, and agree with the results of computer simulation and experimental studies. The article describes methods for constructing the main characteristics of synchronous electric machines on the basis of analytical calculations. Mathematical derivations of functions on the basis of a phasor diagram are given. The extended phasor diagram of a salient pole generator and the algorithm of its construction are given. It is shown that the form of some characteristics does not depend on whether the generator is a salient- or nonsalient pole one. The influence of the armature winding reduced resistance, which is characteristic of medium- and low-capacity power machines, is taken into account. The choice of the magnetomotive force value of the inductor for compensating the armature reaction field to maintain the nominal voltage value is substantiated. On the basis of the obtained characteristics, the ultimate overload capacity is estimated. The article also presents a method for evaluating the field winding parameters and the necessary field current regulation depth to ensure the preset voltage stabilization time in response to changes in the connected load value and type. By using the analytical characteristics, the performance of the electrical machine being designed can be evaluated in different modes of its operation, its shortcomings can be revealed, and necessary changes can be introduced already at the preliminary design calculation stage. The proposed analytical formulas can be algorithmized for the possibility to automatically obtain the calculation results in the form of typical conventional diagrams.

Incorporation of Splitter Units into Process Instrumentation and Control Systems with an RS-485 Interfaces

2025-08-08T08:48:13+00:00

The article addresses matters concerned with achieving more reliable operation of a process instrumentation and control system (PICS) taking as an example the relay processing based electrical interlocking system, which uses an RS-485 interface. It is proposed to incorporate splitter units into the RS-485 interface, a solution that makes it possible to achieve more reliable operation of the automatic and remote-control system and decrease the damage when monitoring and control of facilities is lost. The use of splitter units facilitates and speeds up the process of finding and replacing failed monitoring and control cards, specifically, matrix input devices and discrete end devices. It is shown that splitter units can also be incorporated in other PICS, the components of which use the RS-485 serial interface. The article is intended for specialists in automation, automatic and remote-control systems, as well as for researchers who deal with achieving more reliable and efficient operation of PICS.

Trends in the Development of Electrical Machines for Motor Vehicles and Aircraft

2025-08-08T08:56:13+00:00

The article presents a comprehensive analysis of patent activity in the field of electrical machines (subclass H02K) for the period 2004-2024. The key technological trends and priority areas in the development of the industry are identified. Special attention is paid to the dynamics of patenting and the geographical distribution of innovative activity. The patents issued for the past decade are ranked by groups and subgroups in the H02K subclass, as well as by the types of electrical machines. Based on a patent analysis, the dominant technological areas were identified, among which permanent magnet synchronous machines, new generation cooling systems, and integrated electromechanical solutions can be highlighted. A comparative assessment of the patent portfolios of leading industrial companies and new technology players is given, and the positions of Russian developers in the global technology market are analyzed. The study results demonstrate the growth of patent activity in the last decade, caused by the demand for energy efficient and environmentally friendly technologies. The materials of the article will be of interest for specialists in the field of electrical machinery construction, innovation management and patent analysis.

Kahraman Rahimovich Allaev (to the 80th Anniversary of the Birth)

2025-08-08T08:58:11+00:00