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Main characteristics and advantages of static VAR compensators (SVC) based on thyristor-switched schemes are presented. The operating features of compensator circuits when forming inductive and capacitive reactive power are considered. The reactive power regulation principles that provide the sinusoidal form of reactive current are explained on examples of operation of inductive and capacitive SVCs. The specificity of the operation of SVC control systems ensuring reliable operation in transient and steady-state working modes is discussed. The tasks of experimental research of SVC physical models are formulated. Experimental results obtained on the SVC physical models illustrating main characteristics of such devices are presented.

Technical solutions for optimizing the flame aerodynamics and the design of tangentially arranged burners in a TGMP-314 boiler are proposed. The implementation of these solutions will make it possible to achieve more reliable operation of the boiler during fuel oil combustion, smaller amount of NOx emissions during the combustion of gas and fuel oil, and a somewhat lower air excess factor in the furnace.

This paper analyzes the general issues of sectionalizing 110- and 220-kV distribution grids, including by current limiting. The results of calculations of transients in the event of various disturbances in the distribution network, taking into account the operation of emergency control devices, are presented. The results of comparative analysis of sectionalized and desectionalized distribution grids are presented. The authors hereof propose introducing a load increment safety factor to quantify how sectionalization or desectionalization could affect grid reliability. The paper further substantiates the need for accounting excess disturbances in sectionalized grids to design and implement measures to minimize accident-related losses. It analyzes the effectiveness of applying automatic load transfer (ALT) and draws recommendations on how to implement it.

The article is devoted to calculations of load on rollers of a curvilinear continuous casting machine during bending of the ingot in the levelling section. The calculation takes into account the elastic and plastic characteristics of metal and the flexibility of the roller apparatus. Determination of load on rollers together with meeting other requirements such as reducing the cooling water consumption, minimizing the energy consumption enables optimizing the technology of slab cooling in the secondary cooling zone (SCZ) and obtaining metal of the required quality.

The temperature dependence of the electrical conductivity of the molten eutectic GdCl3(0.515)–KCl(0.485) containing up to 3.3 mol % gadolinium oxide is studied. The temperature dependences of the conductivity of the molten GdCl3–KCl–Gd2O3 system are approximated by second-order polynomials. The formation of gadolinium oxychlorides is confirmed by spectral studies of the solidified melt.

Two approaches to synthesis of unsymmetrical disulfides based on different types of thiol activation, namely, an electrochemical method in the presence of a redox mediator and a microwave irradiation, were discussed. The mediated electrosynthesis procedures were carried out by the oxidative coupling of thiols or by the thiol-disulfide exchange in the presence of redox pairs—substituted o-aminophenol/o-iminobenzoquinone. It has been established that the formation of unsymmetrical disulfides under electrochemical conditions occurs as a result of both the oxidative coupling of sulfur-centered radicals, and a redox-mediator promoted thiol-disulfide exchange, which led to a high yield of heterodimeric products (89%–99%). The microwave-assisted synthesis made it possible to obtain the target products with yields of 13%–86% depending on different irradiation parameters such as power, temperature, and irradiation duration. However, this method requires a rigorous selection of conditions for each reaction and is therefore inferior to the electrochemical approach.

Beyond the anticipated experience associated with tourism destinations, the United Nations World Tourism Organization (UNWTO) has further tasked (especially the destination countries) on the importance of tourism to achieving the 2030 Sustainable Development Goals (SDGs). From this dimension, this study employed the ecological footprint of the 10 most visited countries (France, Spain, United States, China, Italy, Mexico, United Kingdom, Turkey, Germany, and Thailand) over the period 1995-2016. Specifically, the study employed an econometric approach and found that increase in tourism arrivals and globalization is detrimental to the attainment of sustainable environmental quality in a long term. Precisely, a 1% increase in international arrivals and globalization is responsible for a 0.18 and 0.89% increase in ecological footprint in the long-run. These impacts of tourism activities and globalization are detrimental to the environmental quality of the destination countries. Meanwhile, the real income per capita and biocapacity in the destination countries improve the environmental quality of the panel of destination countries in the long-run. In addition, the study found significant evidence of Granger causality from tourism and real income to ecological footprint without feedback, the globalization-ecological footprint Granger causality nexus is with feedback. Moreover, potentially effective policies for government and other stakeholders especially toward attaining Global goals were proffered in the study.

We have developed algorithms and programs for automated tests of synchronous machines. The programs were made using the LabVIEW development system. They are interrelated and have been combined into one software system. An approximation of its characteristics using regression equations of different orders with mean-square rate control is used in the algorithms to determine static parameters. A combined optimizing algorithm that is based on the least squares method and alternating-variable descent method is used to determine dynamic parameters. A new effective and adaptive method of sliding trigonometric interpolation is used to filter out possible noise in measuring channels of voltage and current sensors, while determining the parameters of sinusoidal signals in the stationary modes and dots of envelope curves in the transient modes. To reduce the time needed to obtain static characteristics, the software has a special virtual instrument with a field current control loop with a PID controller that provides desired field forcing. The SMTest software system has been tested using HIL modeling and laboratory test stations. Analysis of test results shows that, even when the acquired signal has a 30% noise level, the calculation error in the determination of parameters does not exceed 6%. The software, when used in stationary or mobile test stations, allows automating the process of obtaining characteristics and determining the main static and dynamic parameters of midand high-power rotor synchronous machines.