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Nowadays, in developed time, there is no sense to speak about importance of different kinds of energy, especially electroenergy. For today’s person impossible image his life without electricity. But, like any other commodity, electricity has such sagnificants like quality, which depends on different factors. Now, when quantity of electrical receivers, which have not long volt-amper characteristics, grow. So electromagnetic compatibility falls down and falling down makes such consequences: breakage of electric receivers, wrong work of defensive and managing systems, huge loosings of electroenergy, in different accidents – growing worse of humans health, falling down of capacity for work, consequently and falling down of labour productivity.
Parameters EMC in the nets with doubled reactor were discerned in my master’s work.
Aim: Definition of parameters of quality of electroenergy in the nets with doubled reactor, influence of double reactor to this parameters, comparing of individual reactor with group reactor and doubled reactor, also evaluating of effective of using of doubled reactor.
Task of the work: Definition of parameters of EMC in the nets with double reactor.
New: Definition of calculated maximum of vibration of voltage in the net with double reactor for normal regime.
Questions of guaranteeing of quality of elecroenergy in electrical nets widely showed in the works of such scientists: I. V. Gegelenko, A. P. Lyutiy, G. M. Kayalov, V. G. Kuznecov, E. G. Kourenniy, A. K. Shidlovskiy and so on.
Doubled reactor is electrical equipment, used for lowering currents of short circuit . Doubled reactor is a single winding with middle infer, calculated for summary current of brunches. This infer is connected to the united tires on the exit of transformer, and the ends of these windings – to the burden. Doubled reactor has to brunches, winded together. Current goes throw these brunches.
During opposite and equal currents are crossing throw one of the reactor’s coil reactive resistance is lowering for the quantity connection coefficient. Last is the most important advantage of doubled reactor. This characteristic gives the opportunity to low voltage in reactor during normal regime in two times. Doubled reactors have lowed dynamic stability, if two brunches are connected in parallel regime for three phased short circuit. Such regime is impossible. In spite of equivalent reactivity of two brunches during such regime is less more then two times of reactivity of each brunch, current of grows to the impossible limits.
Connection coefficient of doubled reactor is limited by allowed voltage level in the brunch, which is switched off, when there is short circuit in another brunch.
According to the standard GOST 13109-97, system of indicators of quality of electroenergy are formed by:
- range of voltage dimantions ;
- dose of flicker ;
- coefficient of distortion of sinusoidal curve of voltage ;
- coefficient of harmonic component of voltage ;
- coefficient of asymmetry of voltage according to the back sequence ;
- coefficient of asymmetry of voltage according to the zero sequence ;
- deflection of frequency ;
- duration of voltage valley ;
- impulse voltage ;
- coefficient of time of overvoltage ;
Principles of rate settings of quality indicators consist of: a) indicators have energetic sense, they characterize power of distortion of curve voltage; degree of negative influence energy to the electrical equipment and technological processes; b) limited allowed values of quality indicators are choosed from technical-economic factors; c) quality indicators are formed during appointed time with set probability for receiving reliable values; d) allowed quality indicators are shown on the electrical equipment terminals and in the units of electrical nets.
System of quality indicators can be used in planning practice, allowing to make mass metrological securing of indicators control with help of easy and cheep instruments and also realize technological means for normalization of electroenergy quality.
Wind energy generators are intensive sources of electromagnetic radiation (mostly vibration of voltage). In fig. 1 is shown general circuit of powerful wind energy generator.
Nowadays received results – effectiveness of doubled reactor according to the range of deflections and dose of voltage vibration depends on character of connection between burned of brunches. During the calculation definite fields of coefficient values, when doubled reactor increases range of deflections and dose of voltage vibration, were found.
Practical value – received results can be used for electrical nets planning, choosing equipment for limiting of short circuit currents.
*Note: Deflections and vibrations of voltage were considered, but all conclusions can be spreaded for another quality indicators of electroenergy. Latest results would be put to the site after ending master’s work
1. ГОСТ 13109-97. Межгосударственный стандарт. Электрическая энергия. Совместимость технических средств электромагнитная. Нормы качества электрической энергии в системах электроснабжения общего назначения. – Введ. в Украине с 01.01.2000. – Введ. в Украине с 01.01.2000.
2. Жежеленко И. В., Саенко Ю. Л. Качество электроэнергии на промышленных предприятиях. 4-е изд., перераб. и доп. -М.: Энергоатомиздат, 2005-261 с.
3. Кузнецов В. Г., Куренный Э. Г., Лютый А. П. Электромагнитная совместимость. Несимметрия и несинусоидальность напряжения. – Донецк: Норд-Пресс, 2005. –250с.
4. Прокопчик В. В. Повышение качества электроснабжения и эффективности электрооборудования предприятий с непрерывными технологическими процессами.- Гомель: Изд-во Гомельского гос. техн. ун-та, 2002- 283 с.
5. Шидловский А. К., Куренный Э. Г. Введение в статистическую динамику систем электроснабжения. – Киев: Наукова думка, 1984. –271с.
6. CEI/IEC 61000-4-15. Electromagnetic compatibility – Part 4, Section 15: Flickermeter – Functional and design specification. 1997.
7. Мукосеев Ю.Л. Электроснабжение промышленных предприятий. – М: Энергия, 1973. – 584 с.
8. Ермилов А. А., Соколов Б. А. Электроснабжение промышленных предприятий - 4- е изд., перераб. и доп. - Г.: Энергоатомиздат, 1986 - 144 с.
9. Липский A. M. Качество электроснабжения промышленных предприятий.- Киев–Одесса: Вища школа, 1985- 160 с.
10. Жежеленко И.В. Электромагнитная совместимость в системах промышленных предприятий.-Электрика, №10, 2008.
http://www.kudrinbi.ru/public/20451/index.htm
11. Рай А. В. Автореферат на тему: «Эффективность сдвоенных реакторов в условиях электромагнитной совместимости».
http://www.masters.donntu.ru/2008/eltf/ray/diss/index.htm