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Abstract

Content

Introduction

The development of electrification and automation of various sectors of the economy contributed to the formation of modern highly mechanized production, in which the interaction of many categories of workers with electric become an everyday.

With the massive use of electrical great importance attaches to the protection of personnel and other individuals associated with the operation of electrical installations, electric shock.

Providing electrical safety is a complex issue that depends on the implementation of the technical and organizational protective measures prescribed by the applicable rules and regulations. In solving this problem it is necessary to simultaneously address the other – ensuring continuity of supply.

To solve this problem is widely used protective shunt single-phase electrical damage, the essence of which lies in the automatic artificial grounding faulty phase. The device is faulty phase selection - one of the units of the system necessary to ensure electrical safety and security of electricity supply. The device is the "intelligent" part of the system that determines the faulty phase and make a decision about how to disable it faulted phase.

1. Theme urgency

Providing electrical safety of electrical installations is an important and challenging task. The urgency of this task can not be in doubt. For security devices are set high demands for speed and reliability. Improper operation, delayed response of such systems can lead to loss of life. Protective systems must evolve and improve with the development of electronics, new methods and principles. In the information age, the age of digital electronics, such systems must acquire the features of intelligent systems. High performance protective systems can reduce the damage caused to a person fell under voltage electrical systems, operating reliability, good stability – reduce the number of false positives, and therefore does not interfere with the production process.

2. The purpose and objectives of the research, the expected results

Purpose - to develop and explore the high-speed system for the identification of damaged phase.

The requirements for this system are inconsistent. On the one side you need maximum performance (human powered). On the other hand, random grafting intact "healthy" phase to the tripping operation is not allowed.

It defines the objectives of the study:

  1. Develop an algorithm that implements a fast way to determine the faulty phase;
  2. Develop a mathematical model of the algorithm;
  3. Explore the limits of reliable operation of the algorithm;
  4. Investigate and minimize the destabilizing influences;
  5. Run a prototype of the system and to its experimental research in the laboratory.

Research object: three-phase electrical network with isolated neutral.

Research subject: a fast and reliable method for determining the faulty phase.

3. Overview of Research and Development

Faulted phase selection device (HLA) are one of the most important blocks of systems security bypass. Due to the high functional responsibility FVS their design and implementation scheme developed most fully in comparison with other units of the protective bypass.

At present, a classification of HLA [1] on the mean values, which are responsive to the measuring bodies:

  1. to decrease the absolute values of the faulted phase voltage or to increase the absolute values of the two phases intact;
  2. the sum or difference of the reference vectors of phase voltages and residual voltage (ANP);
  3. the difference of the absolute values of the phase voltages and PNP;
  4. on the shift angle between the phase voltage and PNP;
  5. the difference of the absolute values of stress and damaged advanced phases;
  6. a combination of several enumerated values;

In modern methods of identifying the faulty phase enormous contribution made Seppo Hanninen, Helsinki University of Technology [2]. His method has high sensitivity and is suitable for the determination of high impedance circuits. The method is based on the analysis of transients that occur when damaged phase and even has the ability to localize the fault on the analysis of wave propagation in the network.

In the Donetsk National Technical University of theme definition faulty phase in networks with isolated neutral is engaged Chernous E.V. He is the author of numerous articles, he proposed a method for rapid determination of the faulty phase in networks with isolated neutral.

This master's work is not completed yet. Final completion: December 2013. The full text of the work and materials on the topic can be obtained from the author or his head after this date.

References

1. Защитное шунтирование однофазных повреждений электроустановок./ Шуцкий В. И., Жидков В. О., Ильин Ю. Н. – М.: Энергоатомиздат, 1986. – 152 с.:ил.
2. Электронная библиотека Aalto University [электронный ресурс] – режим доступа:
http://lib.tkk.fi/Diss/2001/isbn9513859614/isbn9513859614.pdf
3. Об оценке электробезопасности сети с изолированной нейтралью –Чорноус Е. В., Ковалев А. П., Чорноус В. П. // Электричество. ­ 2006. ­ №5. ­ C
4. Аппараты защиты от токов утечки в шахтных электрических сетях – Дзюбан В. С. – М., Недра, 1982. 152 с.
5. Заявка Патент UA на корисну модель № 51307, Україна, МПК H02H 3/16, G01R 31/08, СПОСІБ ВИЗНАЧЕННЯ ПОШКОДЖЕНОЇ ФАЗИ З ВИТОКОМ НА ЗЕМЛЮ В ЕЛЕКТРИЧНІЙ МЕРЕЖІ З ІЗОЛЬОВАНОЮ НЕЙТРАЛЛЮ, Чорноус Є.В., -u201000703, опубл. 12.07.2010, бюл. № 13.
6. Об альтернативном варианте защиты шахтной участковой сети от однофазной утечки // Чeрноус Е.В., – Электричество. – 2009.  – №8. – C.33 – 36.
7. О динамических свойствах быстродействующего алгоритма выбора поврежденной фазы сети с изолированной нейтралью //Чeрноус Е.В., – Наукові праці Донецького національного технічного університету № 10(180), 2011
8. Быстродействующий способ определения повреждений фазы шахтной участковой сети //Чeрноус Е.В., Богданов Д.А. – Кафедра гірничої електротехніки і автоматики ім.Р.М.Лейбова. 10-я международная научно-техническая конференция аспирантов и студентов "Автоматизация технологических объектов и процессов: Поиск молодых". Тезисы доклада. .
9. ГОСТ 12.1.038 – 82. Электробезопасность. Предельно допустимые уровни напряжений прикосновения и токов. Издательство стандартов, 1983
10.Научные основы (теория) электробезопасности.// Малиновский А.А., Никонец Л.А., Голубов С.В. , 2008 – 224с.