Development and application of diagnostic methods and equipment for process monitoring and management; improvement of equipment regarding occurring processes; contemporary production organization, methods and tools for equipment maintenance.
Papers selected for Conference Session titled : Thermal / hydro / wind and other Power Plants exploitation problems
Tobias Bönsel, Dr.Rolf Graf , Bogusław Krztoń - Foster Wheeler Graf Wulff GmbH, Germany
Abstract
Tightening environmental regulations are lowering the requirements for emissions from power plant and industrial facilities around the world. Newer, stricter standards are being required by more governments for pollutants that are already being regulated—SOx, NOx and particulate matter. In addition, metals, acid gases, and organic compounds are setting requirements for flue gas cleaning systems. USA’s EPA Mercury and Air Toxics Standards (MATS) rule enacted in December 2011 and the upcoming IED requirements become completly in force by January 2016 in Europe. Due to the new requirements for flue gas acids like SOx,HCl, HF, dust and many other multi-pollutants, owners of coal fired,oil fired and waste fired power plants are continuously evaluating the merits of adding back-end air quality control systems (AQCS).
This paper takes a special focus to the first operation experiences of Basin Dry Fork station project, which entered in commercial operation 2011, featuring best available dry flue gas scrubbing technology (BAT) for the first time worldwide in single unit size for a 420 -450MWe coal fired boiler plant. It will be shown how the technology is able to meet the strict emission requirements and even more. Furthermore, experiences from an oil-fired refinery boiler in Europe taken into operation in Jan.2012 are highlighted.
The dry technology of Circulating Fluidized Bed Scrubbing (CFBS) is a viable pathway for addressing multi-pollutant control in a cost effective manner. Combining lime hydration and storage equipment, a circulating fluidized bed upflow reactor/absorber and downstream fabric filter, all CFBS system equipment can be installed in one building or outdoor. Construction costs can be reduced as the major system components can be pre-assembled on the ground and lifted into place during system erection.The technology provides high pollutant removal efficiencies up to 99% for SO2, SO3, HCl and HF. Further on the absorber/fabric filter arrangement is highly adaptable for sorbent injection for removal of heavy metals including mercury.
Z. Kovačević, M. Spasojević, A. Ostojić, S. Milić - 1Energoprojekt-Hidroinženjering, Energoprojekt Entel
Abstract
This paper presents the one-dimensional model of unsteady flow in HPP Iron Gates 1 and 2 reservoirs, caused by the combination of both HPP regimes and natural waves entering reservoirs. The model results are used as basis for energy production analysis. The area modeled includes the Danube River between the gauging station Lom (rkm 743+300) and the city of Novi Sad (rkm 1254+150), the Sava River between its mouth (rkm 0+000) and the city of Sabac (rkm 102+850), the Tisa River between its mouth (rkm 0+000) and the city of Novi Becej (rkm 62+350), as well as the mouth areas of smaller tributaries of the Danube (Tamis, Velika Morava, Mlava, Nera, Pek, Porecka, and Timok) and the Sava (Kolubara). The model includes the HPP Iron Gates 1 structure, as well as both HPP Iron Gates 2 structures, one on the Danube River, and the other on the Gogos side channel. The model’s domain is split into three subdomains, the first one covering area upstream from the HPP Iron Gates 1, the second one covering area between HPP Iron Gates 1 an HPP Iron Gates 2, and the third one covering area downstram from the HPP Iron Gates 2. The model’s formulation, calibration, and verification are based on existing bathymetric, discharge, and free-surface elevation data. The model is based on the HEC-RAS program.
M. H. Benišek and I. O. Božić - University of Belgrade, Faculty of Mechanical Engineering
Abstract
Hydraulic turbines’ energy characteristics have been determined by model tests in laboratories and then recalculated to prototype characteristics. Some of the most significant scale-up formulae for dimensionless total hydraulic losses recalculations are given chronologically in this paper. In addition, according to the rare and valuable experimental results of four different dimension models and a prototype of geometrically similar Kaplan turbine, the novel relation of dependency between total hydraulic losses and turbine Reynolds numbers for optimal operation regimes is obtained. Based on this relation, a new scale-up formula is proposed by the authors.
Dane D. Džepčeski, Slobodan S. Bogdanović, Dušan B. Arnautović, Vladimir S. Stanojčić, Jelena S. Pavlović - Electrical engineering institute „Nikola Tesla“ a.d., Koste Glavinića 8a, Belgrade, Serbia - Member of University of Belgrade , Dušan M. Trišić, Boris V. Jovanović - PD „Drinsko-Limske hidroelektrane“, Trg Dušana Jerkovića 1, Bajina Bašta, Serbia
Abstract
In this paper test results of characteristics and parameters of an turbine governing system of one hydro power unit, when unit operates in primary frequency control, are presented. Test results were taken over from the report of testing that was carried out for the needs of power system operator, that is for provider of system service of grid frequency control. Short overview of characteristics and parameters of turbine governing system is shown side by side with test results in order to provide better background for presentation and interpretation of these results. Test results are presented together with criteria defined in current standards and policies that refer to the primary frequency control. Test preparation and testing procedures are described. The results are processed in such a way as to enable their comparison with the corresponding test results obtained from any other unit.
Apstrakt
U radu su prikazani rezultati ispitivanja sistema turbinske regulacije jednog hidroagregata prilikom rada agregata u primarnoj regulaciji učestanosti. Kroz prikaz rezultata ispitivanja opisani su poredbeni kriterijumi koji su definisani u važećoj regulativi i standardima koji se odnose na oblast primarne regulacije učestanosti. Primenjenom metodologijom ispitivanja i analize dobijenih rezultata pokušano je određivanje opšteg pristupa koji omogućava jednostavno poređenje kvaliteta učešća ispitivanih agregata u primarnoj regulaciji učestanosti. Svi prikazani rezultati preuzeti su iz rezultata ispitivanja koja su vršena za potrebe realizacije eksperimentalnog dela studije „Sistemski parametri regulacije pobude i turbinske regulacije u elektranam EPS-a“.
Nemanja Milojčić, Dušan Arnautović, Zoran Ćirić, Đorđe Stojić, Slavko Veinović, Predrag Ninković, Mladen Ostojić, Blagota Jovanović, Rajko Prole, Dane Džepčeski, Marko Janković, Tomislav Gajić, Dušan Joksimović, Mladen Milošević, Milan Milinković, Jelena Pavlović, Jasna Dragosavac, Vladimir Stanojčić - Electrical Engineering Institute "Nikola Tesla" - University of Belgrade, Belgrade, Koste Glavinica 8a
Abstract
In this paper integrated system which is developed for micro, mini and small hydropower plants is presented. The system is complete and uniform set of equipment which can be adapted to different unit powers and different configurations of the main and auxiliary unit equipment in the HPP. Main parts of the system are: LV AC distribution panel, DC distribution panel with rectifier, central control system for main unit and auxiliary equipment, excitation system, turbine governor, synchronizer and electrical protections system. Implemented part of the system and equipment on the 200 kVA unit in mini HPP "Moravica" - Ivanjica are described.
Apstrakt
U radu je predstavljen razvijen integrisani sistem za upravljanje radom mikro, mini i malih hidroelektrana. Sistem predstavlja jedinstvenu celinu koju čini oprema koja se lako može prilagoditi za različite snage hidroagregata i konfiguracije glavne i pomoćne opreme u hidroelektrani. Osnovni elementi sistema su: niskonaponski naizmenični razvod napajanja, jednosmerni razvod napajanja sa ispravljačem, centralni sistem upravljanja agregatom i pomoćnom opremom, sistem pobude agregata, sistem turbinske regulacije, sinhronizator i sistem električnih zaštita agregata. Dat je opis dela sistema i opreme koja je instalirana u MHE "Moravica" - Ivanjica na hidroagregatu snage 200 kVA.
Saša Dragoljub Milić - Electrical Engineering Institute Nikola Tesla, University of Belgrade, Belgrade, Serbia , Nebojša Karanović, Zoran Kršenković - CE Djerdap Hydroelectric Power Plants Ltd. Serbia
Abstract
In this paper we propose a novel laser monitoring system of vessel detection in the lock of hydropower plant Djerdap on Danube river in Serbia. The lock consists of one chamber and top and bottom gates. The proposed monitoring system is a stand-alone class, based on remote laser detection of vessel in the area of gates at both ends of the lock. The system is useful for continuous remote monitoring without interruption water transport. It consists of following parts: four laser sensors (two sensors per gate), two programmable logic controllers, alert device and industrial computer with a few application softwares, database and interface for connection to SCADA. The communication among system parts is done by optical network with appropriate active and passive network components. The paper describes in detail the monitoring concept, placement and routing of sensors and a computer program which performs object detection in the visual field of laser sensors. This monitoring system has a vital role in keeping water transport operations safe, preventive maintenance and avoidance of vessel damaging in the area of gates at both ends that control level of water in the chamber.
Vojin Kostić - Elektrotehnički institut „Nikola Tesla”, Univerzitet u Beogradu, Beograd , Dragutin Salamon - Elektrotehnički fakultet, Univerzitet u Beogradu, Beograd, Srbija , Aleksandar Pavlović, Saša Milić - Elektrotehnički institut „Nikola Tesla”, Univerzitet u Beogradu, Beograd
Abstract
U radu je dat prikaz poboljšane U-I metode za merenje impedanse sistema uzemljenja. Sistemi uzemljenja imaju veoma važnu ulogu tokom normalnog režima rada i tokom perioda trajanja kvara u elektroenergetskom sistemu. Prema važećim propisima obavezno je vršiti periodična ispitivanja sistema uzemljenja da bi se procenila bezbednost ljudi i opreme u periodu normalnog rada i prilikom kvarova. Nedostatak dosadašnjih merenja je što se u velikim elektroenergetskim objektima (termoelektrane, hidroelektrane) nisu mogle izbeći velike smetnje koje su ponekad bile veće od stvarne vrednosti merene pojave. Modifikacijom postojeće metode merenja moguće je izbeći navedeni problem.
Abstract:
This paper presents improved U-I method for the earthing system impedance measurement. Earthing systems have important part during normal operatning mode and during earth fault condition in power system. According present regulations inspections of earthing systems are obligately in aim to evaluate safety of people and equipment during normal operatning mode and during earth fault condition. Absence of present measurements in large power system objects (thermo and hydro power plants) is interference value which is higher then the thru measurement value. Modification of existing method can avoid foregoing problem.
Key words: earthing system impedance, measurements, interference, modificated method
Vladimir Đ. Vukić - Institute of Electrical Engineering “Nikola Tesla”, University of Belgrade, Belgrade, Serbia
Abstract
Results were presented on examinations of two valve-regulated lead-acid (VRLA) batteries AGM SVT 300 after six-year exploitation in two industrial systems of uninterruptible power supply. Batteries of the same type, with the nominal service life of twelve years, operated with similar load and the number of cells, but in various temperature conditions. Battery B1, operating without a proper air-conditioning for a long time, expressed failure of three battery cells (out of total 106). These failures were followed by significant characteristic degradation of another four cells after completion of the charging process of the previously deeply discharged battery. Due to the abrupt degradation of the battery B1 characteristics, it was concluded that its replacement with the new battery was necessary. In the case of the battery B2, exploited with good air-conditioning, characteristics of the 100 battery cells (out of total 102) were spotless during the discharge of the 80% of nominal capacity, as well as during the following charging. From two cells from the battery line, not being from the same batch as the remaining hundred cells was discharged only 30% of the nominal capacity. At the beginning of the charging process of battery B2, the voltage of the two weak cells rose up to 2.55 V, in order to nearly achieve equalization of all the 102 cells in the battery circuit at the end of the charging process. It was estimated that battery B2 might remain in exploitation for a long time, with the eventual replacement of two weak cells. Voltage variations of the weak battery cells were analyzed, as well as their failure mechanisms. Implemented procedure for equalization of the VRLA battery’s cells after accomplishing charging process was described. A practice of batteries operation with rectifiers that would enable their operation during the entire declared service life was proposed.
N.Kartalović - INT
Abstract
The paper presents the tests and analysis of partial discharge and condition diagnostic of turbo generator stator insulation system. It is particularly emphasized the importance of on-line and off-line partial discharge measurement and also the importance of monitoring. Since 2007, the system for permanent monitoring of partial discharges was installed on two turbo generators. Data collected from years of data monitoring of partial discharges are kept in a separate archive while all other diagnostic tests are stored in a database for the generators. This paper presents the results of the condition diagnostic assessment of turbo generator insulation system in a power plant TENT A. This allowed the identification of trends and correlations between specific values and parameters. Measured and analyzed characteristic of insulation system, such as: the phase winding insulation resistance, dissipation factor and capacitance, AC and DC leakage current, high voltage testing and partial discharge, were of interest. This paper presents some results and analysis which indicate the significant changes in the condition of the insulation system. On the other hand, complex diagnostics of insulation system, which relies on the correlation of certain parameters, especially with a partial discharge, indicates the nature of these changes and their lower importance.
Ana Milosevic - INT
Abstract
This paper presents a complete system for permanent monitoring of partial discharges on hydro generators. As part of the revitalization of aggregates in hydro power plant Djerdap 1, system for monitoring partial discharge installs in all six generators. A system for monitoring partial discharge, type ICMmonitor was successfully put into operation on the new (rehabilitated) generator G6. The system is connected to SCADA system. The paper shows the technical solution of that system. In order to achieve the full capacity of monitoring system, it is necessary to do some preliminary testing, so-called mapping of generator. For this purpose, it was assessed partial discharge signal propagation through a stator winding or through a particular branch of phase. The results provide a spectral analysis of partial discharge signals depending on the position of discharge. The signal attenuation in the single measuring channel, cross-talk or the character of cross-talk between phases is also obtained. The paper presents comparative studies of partial discharge on generator made with built-in monitoring system and with portable test device. The initial parameters give the possibility of an effective condition diagnostics of insulation systems during further exploitation. The analysis of partial discharge monitoring during the first year of generator operation is presented.