Actuality of the problem
5572 fires arose in Donetsk region during 2008 (2007 - 5866, -5,0%), with a direct damage of 50 million 652
thousands Uah (in 2007 - 39 millions 068 thousands Uah, +29,7%), side losses made up 104 million 810 thousands Uah (in 2007 are 106 million 298 thousands Uah, -1,4 %),
573 men (2007 - 572-0,2%), including 5 children, perished afire (2007 - 29, -82,8%). On fires 185 people (2007 - 219, -15,5%), including 13 children, were injured last
year (2007 - 23, - 43,5%). More than 20% fires in the Donetsk region take place through fault of electric sources.
The resulted information testify that development of new, more exact as compared to the existent methods of
estimation and prognostication of fire hazard of the systems of power supply 380/220 V is an important scientific technical task, the decision of which serves to strengthening
of the economy of Ukraine.
The work is devoted to the question of prevention of igniting in electric networks, and also to the estimation and
prognostication of events which can result the fires in apartments.
Purpose and tasks of work
is Grounding of methods and means of fire safety of dwellings apartments.
For achievement of the put purpose the next tasks of research were defined:
1. To expose reasons on which fires are in networks of 380/220 V;
2. To conduct the review of existent methods of estimation of fire safety of the electric wirings;
3. To develop a mathematical model, explaining the process of origin of fires in dwellings apartments;
4. To make examples of calculations of fire safety of network of 380/220 V and to investigate basic factors which influence on probability of igniting in the networks of apartments during a year.
Approbation of work
Master's degree job Performances were given a report at scientific conference of students of the electrical Engineering faculty of speciality "Electrotechnical systems of electrical consumption" (Science day, 2009).
The first section
is Devoted to the analysis of reasons on which fires are in networks of 380/220 V and the estimation of statistical
fire strength of the electric wirings security is produced.
The analysis of reasons of fires for period 2004 - 2008 established, that a positive tendency was set in relation to
violation of rules of device and exploitation of electric settings (-2,5%) . Considerable growth of fires from violation of rules of device and exploitation of electric settings
happened in cities: Artemovsk (+32,1%), Druzhkovka (+26,7%), Kharcyzsk (+31,8%), Shakhtersk (+32,4%) and Amvrosievskom (+45,5%), Mar'inskom (+12,5%)
districts.
Figure 1 - The dinamics of fires
from the electrical plants in Donetsk region
(animation: volume - 29,8 КБ; size - 614х344;
a delay between frames - 100 мс;
a delay between last and the first frames - 200 мс; quantity of recycle - 7)
The second section
is Devoted to the analysis of existent methods of estimation of fire safety of the electric wirings.
It is rotined that development of mathematical models with the use of chains is Markov with the eventual number of the states and continuous time allows more precisely, than existent methods to forecast probability of origin of igniting during exploitation of the electric wirings.
The third section
is Devoted to the development of mathematical model which allows to find out influence of device of the protective
disconnecting on fire safety of network of power supply of buildings [7]. In obedience to this model probability of finding of the system in each of the possible states
during time t determined from the following system of equalizations [8]:
The fourth section
The example of calculations of fire safety of network of 380/220 V and to research of factors, influencing on probability of igniting in the networks of apartments are resulted.
Conclusion
1. Prognosis of the number of fires from the currents of short circuit in Donetsk region for 2008 showed that the number of fires
makes up 1 527, and in 2009 will make up 1 605.
2. Using statistical information about fires from the different types of electric plants of apartments in Donetsk region after 2000, statistical level of their fire
strength of N security was defermined Н = 6,35*10-4 1/year and a confidence interval is got j0,95 = [2,41*10-4; 10,27*10-4].
3. It is set that if in the system of power supply of apartment for the increase of fire safety of network the protective disconnecting is used, then intensity of ignition in a network will decrease in 297 times.
4. The degree of influence of prophylactic examinations of the system of disconnecting of protective interconnect vehicle (circuit breaker) and device of the protective disconnecting is set on fire
safety of network.
Literature
1. Пустыльник Е.И. Статистические методы анализы и обработки наблюдений - М.: Наука,
1968. - 288 с.
2. Котов А. Оцінка рівня вибухопожежної небезпеки технологічних установок
і об'єктів різного призначення з використанням розрахунку ризику. Пожежна безпека - №12 -
1998. - С. 39 - 40.
3. Иванов Е. Электрооборудование как источник пожара. Новости электротехники - №6 - 2001./ -
Режим доступа к статье: http://www.news.elteh.ru/arh/2001/12/18.php
4. Волошаненко О. Електротехнічні вироби - причина пожежі. Пожежна безпека / О. Волошаненко, Р. Кравченко -
№1 - 1999. - С. 26-27.
5. Васин А.А. О прогнозировании экзогенных пожаров по Донецкой области. Сборник научных трудов ДонГТУ /
Васин А.А., Ковалев А.П., Шевченко О.А., Чурсинова А.А., Нагорный М.А.
Серия: «электротехника и
энергетика» - № 4: Донецк: ДонГТУ, 1999. - С. 214-216.
Режим доступа к статье: http://masters.donntu.ru/2005/eltf/timofeev/library/library/article1.htm
6. ГОСТ 12.1.004-91 «Пожарная безопасность»./ -
Режим доступа к статье: http://www.gostbaza.ru/Index/3/3254.htm
7. Васин А.А. Патент № 2172050 Россия. Устройство для защитного отключения электрических сетей /
А.А. Васин, М.А. Нагорный, И.В. Белоусенко, М.С. Ершов, Д.И. Дубровский, С.И. Кавицкий,
А.П. Ковалев, В.П. Муха, О.А. Шевченко - Приоритет от 21.01.2000 г. Опубл. 10.08.2001,
Бюл. № 22. - 8 с.
8.
Шевченко О.А. О влиянии устройства защитного отключения на пожарную безопасность сети
380 - 220 В в жилых квартирах. - Сборник научных трудов ДонНТУ. Серия: «электротехника и
энергетика», выпуск 50. - Донецк: ДонНТУ, 2002. - С. 141-143./ -
Режим доступа к статье: http://masters.donntu.ru/2005/eltf/timofeev/library/library/article4.htm
9.
Ковалев А.П. Оценка экономической эффективности работы средств защиты,
обеспечивающих пожарную безопасность электрических проводок./ А.П. Ковалев, О.А. Шевченко
- Сборник научных трудов ДонНТУ.
Серия: «электротехника и
энергетика», выпуск 50. - Донецк: ДонНТУ, 2002. - С. 144-146./ -
Режим доступа к статье: ../library/article1.htm
10.
Кашолкин Б.И. Тушение пожаров в электроустановках./ Б.И.Кашолкин, Е.А. Мешалкин - М.: Энергоатомиздат, 1985. - 112 с.
At writing of the given abstract a master’s work has not been finished yet. Date of the work’s final end is on December, 1st, 2009. Full text of work and materials on a theme can be received from the author or her supervisor after the named date.
