Conference Power Plants 2010 | Konferencija Elektrane 2010

List of Accepted Papers for Conference

List of submitted papers and abstracts that have been accepted for the presentation at the Conference Power Plants 2010 | Konferencija Elektrane 2010

• OSNOVNE SPECIFIČNOSTI POJEDINIH DELOVA POSTROJENJA ZA SPALJIVANJE TKO SA ISKORIŠĆENJEM TOPLOTE DIMNIH GASOVA

  Šefik Bajmak - University of Priština, Kosovska Mitrovica, Serbia
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: SefikBajmak
  Abstract text

  Pojedini delovi postrojenja za spaljivanje tvrdog komunalnog otpada sa iskorišćenjem toplote dimnih gasova su zbog osobine samog otpada , vrlo specifične i razlikuju se od odgovarajućih delova postrojenja koja su predviđena za rad sa klasičnim čvrstim gorivima. U radu će biti reći o mehanizmu sagorevanja goriva, skladište za otpad, čelične rešetke , ozid ložišnog prostora i kotlu utilizatoru i onome što ih čini specifičnim. Biće prikazan postpak proračuna i izbor skladišta za otpad, levkasti uređaj, proračun i izbor čeličnu rešetku i njeno toplotno optrećenje , opis ozida ložišnog prostora i ložišna komora i proračun toplotnog optrećenja, i opis i tehničke tehnološke karakteristike kotla utilizatora, i analiza preostale pomoćne oprema.

• PROPOSAL FOR ADDITION OF IEC 34-4 STANDARD IN PART FOR DETERMINATION OF POTIER REACTANCE

  Miloje M. Kostić - Electrical Engeneering Institute Nikola Tesla, Belgrade, SERBIA
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: generator
  Abstract text

  In this paper is proposed change and addition of the Standard IEC 34-4/1985, "ROTATION ELECTRICAL MACHINES, Part 4: Methods for determining synchronous machine quantities from tests" in part for determination of Potier reactance [1]. One is proposed that it determined by of the excitation current corresponding to the rated voltage and armature current value i’ = ian∙sinφn, at zero-power factor (overexcitation), and for some characteristic values which would be convenient for construction of turbogenerator capable curve (P-Q curve). Namely, on the base of ones investigations results [2] author comes to new conclusion: that the Potier reactance values depend practically only from of turbogenerator reactive currents (iaQ = ian∙sinφ), for given voltage values. This new rule is proved: a) first, by qualitative analysis, and b) then it is checking on the example of the considering turbogenerator GTHW 360 (360 MW), for the region of active and reactive loads relevant values [2, 4]. Potier reactance values (xP) are determined with sufficiently accuracy by new method which is published recently by this author [3]. Standard graphical method is used for determination of Potier reactance by the following data [1]: a) from the no-load saturation and sustained three-phase short-circuit characteristics, and b) of the excitation current corresponding to the rated voltage and rated armature current at zero power-factor (overexcitation). If, during overexcitation test at zero power-factor, the voltage and current differs from rated value by not more then ± 0.15 per unit, a graphical method is used for the determination of the excitation current corresponding to the rated voltage and current [1]. On the contrary, author this paper proposes that overexcitation test at zero power-factor be performed for three (four) values armature current (Ia) and corresponding generator voltages, i.e.: 1. Ia1 = Ia,max > IaN∙sinφN (i.e. Q1 > QN), which is corresponding to excitation rated current (If = IfN) and UG1 = UG at Q1 = Qmax > QN; 2. Ia2 = IaN∙sinφN (i.e. Q= QN) and UG2 = UG at Q2 = QN; 3. Ia3 = 0.5IaN∙sinφN (i.e. Q≈ 0.5QN) and UG1 = UG at Q1 = 0.5QN; and 4. Ia4 = (Ia1 Ia2 )/2, if Ia1> (1.3÷1.4) IaN∙sinφN. For different reduced excitation current values (for rated voltage and armature current) if (A1) < if (A2) < if (A3) different values of Potier reactance are obtaining, i.e.: xP (A1) < xP (A2) < xP (A3) On the base of these characteristic values of Potier reactance one would be constructed the corresponding capability curve (P-Q curve) of the test generator. PREDLOG ZA DOPUNU STANDARDA IEC 34-4 U DELU ZA ODREĐIVANJE POTJEOVE REAKTANSE M. M. Kostić* Elektrotehnički institut Nikola Tesla, Beograd, SRBIJA* Abstract: U radu se predlaže promena i dopuna relevantnog standarda IEC 34-4/1985: "ROTACIONE ELEKTRIČNE MAŠINE, Deo 4: Metode za određivanje parametara sinhronih mašina na osnovu ispitivanja", u delu koji se odnosi na određivanje Potjeove reaktanse [1]. Daje se predlog da se ona određuje iz ogleda reaktivnog opterećenja sa strujom i’ = ian∙sinφn, kao

• NOVEL DIGITAL GOVERNOR FOR HYDRAULIC TURBINE

  Dane Džepčeski, Dušan Arnautović, Jelena Pavlović, Slobodan Bogdanović - Electrical Engeneering Institute Nikola Tesla, Belgrade, SERBIA
  Session Power Plants life cycle extension, new clean coal technologies | Produženja radnog veka elektrana i novih ekološki čistih tehnologija
  Submitted By: danedzep
  Abstract text

  In this paper electrical part of the novel turbine governing system for the hydraulic turbines is shown. Presented system is designed for station service power generator in HPP „Bistrica“. However, the concept of the system is of general purpose. There is ability to upgrade, both hardware and software, as to functionality of the system. Considerable flexibility of the system structure enables its adaptation to any type of hydraulic turbine, either that the turbine flow is controlled by one or by number of electrohydraulic converters. Special attention is given to the new speed and active power digital governor. Functions and features that a modern turbine regulation system should have are listed and systematized. Implementation of these functions is described and features of the particular turbine governor are shown. Hardware platform and associated software required for the execution of control and regulation functions are presented, as well as realisation of the interface to the superior control system and to the operator. Test setup with the simulator of the turbine governor environment is described. Processes in the turbine instalment are modeled in the simulator. Model of the hydrosystem, intake and penstock, hydraulic turbine, hydraulic servomotor, model of the electric generator and its load are included in the simulator. Regulation loop that consists of the real digital turbine governor based on programmable logic controller and of simulator that is based on digital computer is shown. Analog and digital signals interchange between the governor and the simulator is performed in the real-time, wherewith testing of the regulation function and its adaptation and parametrization in the real-time is enabled. Test results of the novel digital turbine governor on the simulator are shown. Also the comparison of these results with the results of field test of the existing hydro-mechanical turbine governor in HPP „Bistrica“ is presented. НОВИ ДИГИТАЛНИ РЕГУЛАТОР ХИДРАУЛИЧНЕ ТУРБИНЕ (Преференцијална тема 2 и 4) Садржај: У раду је приказан нови електрични део система за турбинску регулацију хидроагрегата. Приказани електрични део система за турбинску регулацију намењен је агрегату сопствене потрошње у ХЕ „Бистрица“. Међутим, концепција система је опште намене. Постоји могућност његове надоградње и проширења како у хардверском тако и у програмском, односно функционалном смислу. Флексибилност структуре омогућава њено прилагођење свакој врсти хидрауличне турбине, било да је проток флуида кроз турбину регулисан радом једног или више електрохидрауличких извршних органа. Посебна пажња посвећена је новом дигиталном регулатору брзине и активне снаге агрегата. Функције и особине које један савремени систем за турбинску регулацију треба да поседује наведене и систематизоване су у раду. Описана је реализација ових функција и приказане су карактеристике турбинског регулатора. Приказана је хардверска платформа регулатора као и придружена програмска подршка, потребна за извршавање управљачких и регулационих функција, као и за реализацију везе са надређеним системом управљања и везе са руковаоцем. У раду је описано испитно поље са симулатором околине турбинског регулатора. У симулатору околине турбинског регулатора моделирани су процеси у турбинском постројењу. Симулатор садржи модел хидросистема, турбине, извршног органа за регулацију турбине, генератора и оптерећења генератора. Приказана је остварена веза између реалног турбинског

• Control of combustion process in steam boilers of Thermal Power Plant “Nikola Tesla B” (2 x 620 MWe)

  Zoran Stojanović, Miloš Milić, Milorad Jovanović - Thermal Power Plants „Nikola Tesla“ Obrenovac, Serbia
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: ZoranStojanovic
  Abstract text

  Steam boilers of the Thermal Power Plant „Nikola Tesla B“ (TENT B) are designed for the lignite from the coal mine „Kolubara“ as the main fuel. The main design parameters of the guarantied coal for the steam boilers of TENT B are as follows: the lower heat capacity value is 6.999 MJ/kg, the moisture content is 47.8 %, the ash content is 19% and the content of sulphur is 0.5 %. The divergence of the coal quality parameters within the range of ±5 % enables the optimization of the combustion process in the furnaces of the steam boilers of TENT B. However, due to the lack of homogenization, i.e. the equalization of the coal quality, the lower heat capacity of the coal supplied to the Thermal Power Plant is in the range from 5 till 9 MJ/kg. Having in mind the increased needs for the electricity in the Republic of Serbia, the management of TENT decided to start the activity on the increase of the rated electric power of the Units of TENT B from 620 to 670 MWe. The increase of the Units power requires better control of the combustion process in the boiler furnace with the aim of optimal heat transfer to the heated surfaces. A set of measures and activities that are called the control of the combustion process have been taken with the aim of proper combustion organization (the fire adjustment). In order to enable the control of the combustion process the thermotechnical analyses of the Units have been performed, several design projects have been done (the increase of the fan mill capacities, calculation of the boiler thermal and hydraulic processes, etc. ), the built in of louvers in order to properly distribute the coal dust, the installment of the cameras for the visual observation of the combustion and the pyrometers for the observation of the fire position, as well as other projects that are underway and that will contribute to the safety, availability, reliability, increase of the energy efficiency and increase of the power of the Units at TENT B. The paper presents the advances, the applied equipment and the reconstructions that enable the combustion control in the boilers of the Units of TENT B. Управљање процесом сагоревања у котловима блоковаТЕНТ Б (2 х 620 MW) АБСТРАКТ Котлови блокова ТЕНТ Б, пројектовани су за основно гориво – лигнит из лежишта „Колубара“. Основни пројектни параметри гарантованог угља за котлове ТЕНТ Б су: доњи топлотни ефекат (ДТЕ) 6,999 MJ/kg, садржај влаге 47,8 %, садржај пепела 19%, садржај сумпора 0,5 %. Одступање параметара квалитета угља у границама ± 5%, омогућавају оптимизацију процеса сагоревања у ложиштима котлова ТЕНТ Б. Међутим, због недостатка хомогенизације тј. уједначавање квалитета угља, квалитет испорученог угља за термоелектране креће се у границама од (5 ÷ 9) MJ/kg. Имајући у виду повећане потребе за електричном енергијом у републици Србији, Пословодство ТЕНТ_а донело је Одлуку да се на основу пројекта ЕКО-РАМ приступи активностима на повећању номиналне снаге блокова ТЕНТ Б са 620 на 670 MW

• INFLUENCE OF COAL QUALITY TO AUXILIARY POWER CONSUMPTION OF POWER UNITS IN THE THERMAL POWER PLANT "KAKANJ"

  Ilijas Hasanbegović, dipl.ing.maš., Tica Dino, dipl.ing.maš. - Thermal Power Plant "Kakanj", Kakanj, Bosnia and Herzegovina
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: DinoTica
  Abstract text

  The thermal power plant Kakanj fires mixture of seven different kind of coals. These coals differs according to chemical composition as well as lower heat value. Lower heat value of the coal lies within the range of 8.000-16.000 kJ/kg, while ash content varies between 13% and 49%. During inadequate mixing of coal at the depot, quality of coal that is fired in boilers, causes certain problems in boiler operation. These problems manifest in increase of temperatures of flue gases along the furnace, increased amperage of coal feeder lines, extended duration of coal and ash transport. This paper shows how chemical composition and lower heat value influence to increase and decrease of auxiliary power consumption of units in the Thermal power plant Kakanj.

• EXPERIENCES WITH THE HYBRID FILTER OF THE UNIT 5 IN THE THERMAL POWER PLANT "KAKANJ"

  mr Kemal Bečić dipl.ing., Dino Tica dipl.ing., Enez Đakovac, dipl.ing. - Thermal Power Plant "Kakanj", Kakanj, Bosnia and Herzegovina
  Session Environmental aspects of power generation | Ekološki i klimatski aspekti rada elektrana
  Submitted By: DinoTica
  Abstract text

  Modern electrostatic precipitators and bag filters achieve dedusting efficiency of more than 99,95%. While efficiency of dedusting of electrostatic precipitators considerably decreases for particles of size 0,1-1 m, fabric filters withhold high efficiency of dedusting in wider range of particle sizes. However, fabric filters often experience problems with bag cleanability and high pressure drop, resulting in large and costly casings. Hybrid filters are new concept of dedusting that combines advantages of electrostatic precipitators and bag filters. Because of mentioned characteristics »hybridization« of electrostatic precipitators on existing thermal power units is interesting alternative. Bad experiences in operation of electrostatic precipitator in the Thermal power plant Kakanj, as well as necessity of fulfilling legal limitations of particles emission lead to decision to upgrade existing unit 5 precipitator with bag filter. This paper outlines experiences collected during the operation of hybrid filter of the unit 5 in the Thermal power plant Kakanj, which could be useful since so far there was no experience with such plants in Bosnia and Herzegovina.

• Širina zone hlađenja vlažnog rashladnog tornja bloka A5 110MW TE ''Kolubara A''

  Mirjana S. Laković - Mašinski fakultet u Nišu, Slobodan V. Laković - Mašinski fakultet u Nišu, Mladen Stojiljković - Mašinski fakultet u Nišu
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: lmirjana
  Abstract text

  Postrojenja koja koriste povratne sisteme za hlađenje kondenzatora su podložnija dnevnim promenama uslova rada usled promena parametara atmosferskog vazduha. Dok kod sistema sa protočnim hlađenjem temperatura rashladne vode utiče u smislu promene srednje temperature prirodnog vodotoka kojim se hlađenje kondenzatora vrši, kod postrojenja koja koriste rashladne tornjeve stalna promena i temperature i relativne vlažnosti vazduha značajno utiče na temperaturu vode ohlađene u tornju. Ova promena temperature na izlazu iz rashladnog tornja znači i promenu temperature rashladne vode kondenzatora, što opet vodi promenama uslova rada kondenzatora u vidu promene pritiska kondenzacije i mogućnosti kondenzatora da odvede otpadnu toplotu iz ciklusa po kome postrojenje radi. Promena temperature atmosferskog vazduha, te temperature rashladne vode za odvođenje otpadne toplote iz kondenzatora termoelektrana neminovna je kako na godišnjem, tako i na dnevnom nivou. Na osnovu podataka o rashladnim tornjevima i samom postrojenju, dobijenim sa referentnog postrojenja TE ’’Kolubara A’’ na osnovu uvida u dokumentaciju, uradjena je automatizacija proračuna sistema rashladne vode referentnog postrojenja, sa ciljem da se što bolje sagleda rad navedenih tornjeva u promenljivim uslovima. Na osnovu matematičkog modela i konstrukcionih podataka o rashladnim tornjevima bloka A5 termoelektrane ’’Kolubara A’’ u Velikim Crljenima kod Lazarevca, dobijena je zavisnost temperature ohlađene vode od više različitih uticajnih parametara. U ovom radu prikazana je dnevna promena temperature vode ohlađene u tornju za slučajno izabran prosečan letnji dan, kao i promena temperature ohlađene vode na godišnjem nivou, pri čemu su korišćeni parametri atmosferskog vazduha dobijeni sa automatske meteorološke merne stanice ''Kolubara A''.

• Analiza pojava u mreži 6 kV pri razvlačenju električnog luka

  Dragan Ristivojević, dipl.el.ing., Zoran Milosavljević, el.tehn. - RB “Kolubara”, Lazarevac, Srbija
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: Zoran.Milosavljevic
  Abstract text

  Razvlačenje električnog luka predstavlja prelazni proces, koji uzrokuje izvesno naprezanje elektroopreme u mreži 6 kV, koja je izolovana. Zanimljivo je analizirati vrednosti naponske i strujne nulte komponente, pogotovu u odnosu na takozvani metalni zemljospoj. Poznato je da su prenaponske pojave veoma izražene u izolovanim mrežama, bilo da se radi o manipulacijama prekidača, ili tzv. intermitenciji, koja nastaje pri razvlačenju električnog luka odnosno ostvarenju nestabilnog zemljospoja. Pojava direktne i inverzne komponente napona i struje pri ovom eksperimentu, je takodje interesantna za analizu.

• Specifičnosti pri merenju otpora uzemljenja U-I metodom

  Slobodan Damnjanović, ing.el.tehn. - PD RB "Kolubara - Površinski kopovi" Lazarevac
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: SlobodanDamnjanovic
  Abstract text

  Koliko god da je naponsko-strujna metoda merenja otpora uzemljenja standardna pri samoj empiriji javljaju se određene specifičnosti. Bitan detalj je izbor pomoćnog uzemljivača. Hoće li to biti uzemljivač stuba koji je preko zaštitnog užeta galvanski spojen sa merenim uzemljivačem, čime je formirana nepoželjna strujna petlja? Može se traka uzemljivača stuba razdvojiti od mase čelično rešetkastog stuba. Tada su dobijeni rezultati tačniji. Ipak dobro je obezbediti poseban pomoćni uzemljivač upotrebom nekoliko međusobno povezanih sondi. Treba postići dovoljno malu vrednost otpora da bi merna struje dostigla vrednost od bar tridesetak ampera, koliko bi bilo dovoljno da se izbegne uticaj lutajućih struja.

• Energy efficiency annual change for the steam block with closed-cycle cooling system

  Mirjana S. Laković - Faculty of Mechanical Engineering Nis, Slobodan V. Laković - Faculty of Mechanical Engineering Nis, Mladen Stojiljković - Faculty of Mechanical Engineering Nis, Dejan Mitrović - Faculty of Mechanical Engineering Nis
  Session Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana
  Submitted By: lmirjana
  Abstract text

  Temperature changes of atmospheric air and thus of temperature of cooling water for the removal of waste heat from power plant condensers is inevitable on the annual and daily basis. Power plants that use closed systems for cooling condensers are vulnerable to daily changes in working conditions due to changes in the parameters of atmospheric air. Change in cooling water temperature leads to increasing of condensing pressure in order to maintain production at desired levels at the expense of increased specific heat rate. This will cause changes of the energy efficiency on the daily and annual level. Based on the meteorological parameters for the considered area, absolute change of condensing pressure due to change in relative humidity and temperature of atmospheric air for a given plant is calculated for 2009. Taking into account the premise that with the increase of pressure in the condenser of 1 kPa, efficiency decreases to 1.0 - 1.5%, annual energy efficiency of the plant change in the function of changes in temperature and relative humidity of atmospheric air is obtained.