Technique of creating a sub-line diagnostics status turbine unit thermal power plant based on an analysis of its diagnostic features. Rapid assessment of the technical state of turbine unit allows an early stage to detect the possibility of an emergency and to localize it. It involves the integration of the subsystems of the existing process control system (PCS), which will allow more efficient use of its information, hardware and software. Evaluation of the technical condition of the turbine unit thermal power plant is proposed to determine the use of modern intelligent technologies. The proposed method was used in the development of rapid diagnostic subsystems technical state of turbine of thermal power in Almaty.
PL
Zaproponowano metodykę opracowania podsystemu dynamicznej diagnostyki stanu turbogeneratora elektrowni cieplnej, która bazuje na analizie jego cech diagnostycznych. Dynamiczna ocena technicznego stanu turbogeneratora pozwala na wykrycie we wczesnym stadium awaryjnych sytuacji i jej lokalizacji. Proponuje się integrację tego podsystemu z istniejącym systemem automatycznego sterowania procesem technologicznym, co pozwoli bardziej efektywnie wykorzystać jego informacyjne, techniczne i programowe zabezpieczenia. Ocena technicznego stanu turbogeneratora elektrowni cieplnej proponuje się określić z wykorzystaniem współczesnych technologii inteligentnych. Zaproponowana metodyka była wykorzystana przy opracowaniu podsystemu diagnostyki dynamicznej stanu technicznego turbogeneratora w elektrowni cieplnej w Ałmaty.
One of the methods of obtaining energy from renewable sources is the biomass gasification. For economic reasons, and taking into account the security aspects, it is important to ensure that the process is optimal. The gasification process can be optimized regarding the product energy, especially concentration of hydrocarbons and their derivatives or tar substrates, such optimization requires precise knowledge of temperatures in the gasification reactor. The temperatures inside the reactor determine the speed and quality of gasification process and are one of the most important parameters for control and monitoring systems of gasifier operation. Thermocouples are most widely used for temperature monitoring. That is the reason why it is important to acquire precise temperature readout regardless of aging processes. The significance of accurate temperature determining has been demonstrated with the use of a simplified mathematical model of a reactor assuming ideal reagents mixing. The presented mass and energy balance equations have led to determine the temperature changes during the analyzed process. The final equation is a base for the optimization of the gasification process and contains quantity of measured temperature. The main problem is the accuracy of temperature measurement. The authors have developed the in-situ method of diagnostics of thermocouples, that allows determination of the relative deviation of the sensor thermoelectric force during its operation. Besides characteristic parameters such as material properties the model includes the internal heat transfer, as well. The presented diagnostic method consists in determining the electromotive force of a newly installed sensor, and then determination of characteristic parameters using two selected values of testing current. During operation of the monitored sensor, periodic determination of the relative deviation of the Seebeck coefficient is required. This relative deviation should be compared to its permissible level, that is specified for the process being monitored. The proposed method belongs to the class of comparative ones, where the comparison is related to the indications of the same sensor (the new one and in-service). Experimental verification of the presented method was carried out using gasifier with nominal thermal load of 50kW, fed with wood pellets. The temperature of synthesis gas was measured by the two sensors, the reference sensor and the second one, that was driven by pulses of a testing current. For both current directions the thermoelectric force has been determined. The difference of the obtained electromotive forces is diagnostic information, that is needed to calculate the relative change of the Seebeck coefficient. The proposed solution allows diagnosing thermocouples located in confined areas. Moreover, additional benefit is the possibility of sensors diagnosis without stopping the process being monitored. It is important for both economic and technological reasons.
One of the methods of increasing the overall biomass share in the electricity and heat production is its gasification and subsequent co-combustion of the obtained syngas in conventional power boilers. The process of biomass gasification is relatively well controlled and understood. It does not change the fact that the syngas composition depends on many process factors, as well as the composition of the charge batch. Unfortunately, it means that the obtained product is not homogeneous in time. Consequently, the use of such fuel for electricity production may present a number of problems from the control point of view. Therefore, both during the syngas production and the co-firing process, it is advisable to use information on the composition of produced syngas, or at least its main components. It is possible to use optical methods, which are an interesting alternative to classical methods, even despite unfavorable measurement conditions. The article presents selected optical method for the synthesis gas monitoring. The results of simulation studies are presented, confirming the possibility of determining the concentration of interesting components in the syngas mixture.
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The paper evaluated the vascular tone and character of the local blood flow using photoplethysmographic device to determine the viability of the studied organ and prospects for its preservation.
PL
W pracy przedstawiono ocenę sygnału naczyniowego i charakter lokalnego przepływu krwi z użyciem urządzeń fotopletyzmograficznych do oceny żywotności badanego narządu i perspektywy jego zachowania.
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