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cddsfcer This work presents a model of a transformer substation with parallel connection of independent consumers via vacuum switches. Several options of an electric arc model are considered upon switching off a vacuum switch such as: KEMA model and "black box" model. Modern computer models of vacuum switches were analyzed. Since the model data were not suitable for the conditions of the experiment, a simulation computer model was developed that reflects the specifics of the operation of the substation and of the transition process upon disconnection of one or several vacuum switches. The results of the developed methodology of analyzing transition processes were verified. To check the results of computer simulation, an experimental model was constructed, it consisted of: an electric load (inductive nature), a power supply, two vacuum switches, and a measuring circuit. The circuit is switched on and off using a pneumatic system controlled by a microcontroller. The primary purpose of the work is to check mutual influence of vacuum switches upon parallel disconnection, since there may be a restrike caused by effects of switching overvoltage between neighboring switches upon irregular disconnection. The effects of a transition process in one switch on the total current of the entire system were identified. A stand for a projected trial was demonstrated as well. With continuing development of science and technology, high voltage electrical equipment performance has been improved very fast, and dashed out some of the new switch gear, for example, the F-C circuit. Through understanding and analyzing the principle, characteristic and function, etc of F-C circuit , describes its advantages in some areas relative to the circuit breaker, For example, the protection of a more timely, overvoltage lower, functions in line with more reasonable; the lower cost for. Purpose is to allow engineers to correct reasonable selection of high voltage switch when used in the design and to promote domestic F-C circuit development. The design, operation and use are characterized for high voltage vacuum contactors in underground coal mines endangered by methane and coal dust explosions. Design of a vacuum contactor is shown in a scheme. Vacuum contactors are superior to electromagnetic contactors. Vacuum contactors have a reduced size and weight and are characterized by improved commutation properties. Under vacuum conditions, intensity of electric discharges is lower than in an electromagnetic contactor. Reliability of vacuum contactors is 16 to 20 times higher than that of electromagnetic contactors (90% of metal vapors caused by an electric arc settle on contact surface). No time consuming buildup removal or cleaning is necessary. Optimizing contactor position in a power system in underground mines is discussed. Efficiency of using vacuum contactors and the RC systems is discussed. Vacuum contactor is an electrically controlled switch that is used to make or break an electrical circuit with the help of vacuum interrupter, relay, and fuse. The drivers of the this market are influenced by the trends in the commercial sector and by the trends in the process and manufacturing industry. Growth in the related as well as complementary markets, such as motors, capacitors, switchgear, and transformer, also contribute towards the growth of vacuum contactors. The global vacuum contactor market size is estimated to reach $4,814.6 Million by 2020 from $3,426.8 Million in 2015. Vacuum contactor is an electrically controlled switch that is used to make or break an electrical circuit with the help of vacuum interrupter, relay and fuse. It is mainly found in motor starters, switchgear and control gear of medium voltage fast switching devices. The drivers of the high voltage vacuum contactormarket are influenced by the trends in the process industries, manufacturing industries, commercial and large residential sectors that use HVAC systems. This market study covers medium voltage vacuum contactors of various voltage ratings, applications, and end-users for arriving at the global market size from 2013 to 2020. In terms of voltage rating, the vacuum contactor market is segmented into four divisions: less than 5kV, 5-10 kV, 10-15 kV and more than 15kV. On the basis of application the vacuum contactors market is classified into six segments: motors, transformers, capacitors, reactors, resistive loads and others (such as generators, pumps, variable frequency drives, feeders, power transmitters and switchgears). Motors, transformers and capacitors are the top three applications of this industry that covers more than 65% market share. On the basis of end-use, the vacuum contactor market is segmented into six sectors: utilities, industrial, commercial, mining, oil & gas and other medium voltage end-users. The other sector includes marine, water & waste water pumping, street lighting and transportation sector. In terms of region, the single phase vacuum contactor is segmented on the basis of its market presence in the following regions namely North America, South America, Europe, Asia-Pacific and Middle East & Africa. These regions are further classified on the basis of top countries and their end user analyses have been made. Asia-Pacific held the largest market share owing to growth in industrialization and urbanization, followed by Europe and North America. The global vacuum contactor market is projected to witness high growth on account of rising energy demand, growing commercial and industrial sector, and increased up-gradation of electrical infrastructure. The market was valued at $3,210 Million globally in 2014 and is projected to grow at a CAGR of 7.04% from 2015 to 2020. The Asia-Pacific region holds a majority of market share owing to urbanization and significant development in process industries such as paper & pulp, cement, metal processing industries, and growth in manufacturing industries, followed by North America and Europe. In terms of individual countries, the U.S. and China show high growth potential. This growth can be attributed to the increasing demand for reliable power and investments for replacing aging T&D infrastructure in the U.S. and progressive economic growth of China. Amongst the end-users, utilities sector is estimated to hold the major market share owing to increasing installation of power infrastructure. North American region is currently focussing on grid modernization and replacement of existing power infrastructure. Few countries in Europe are shifting towards renewable sources for power generation that has boosted the low voltage vacuum contactor market in the region. Vacuum contactor finds vast application in industrial and commercial sectors as well. In terms of growth strategies, market players have mainly been forming mergers and acquisitions in order to expand as well as strengthen their market foothold. Contracts & agreements is the most commonly adopted strategy that is followed by mergers & acquisitions, and expansions. This shows a mix of both organic and inorganic growth strategies. Leading players in the industry, based on their recent developments and other strategic industrial activities, include ABB Ltd. (Switzerland), Eaton Corporation Plc. (Ireland), Mitsubishi Electric Corporation (Japan), Schneider Electric SE (France), and Siemens AG (Germany). With continuing development of science and technology, high voltage electrical equipment performance has been improved very fast, and dashed out some of the new switch gear, for example, the F-C circuit. Through understanding and analyzing the principle, characteristic and function, etc of F-C circuit , describes its advantages in some areas relative to the circuit breaker, For example, the protection of a more timely, overvoltage lower, functions in line with more reasonable; the lower cost for. Purpose is to allow engineers to correct reasonable selection of high voltage switch when used in the design and to promote domestic F-C circuit development.
