The operation efficiency increase of the turbogenerator cooling system of the PT-60-130/13 turbine at the Bila Tserkva TPP.
Students Name: Maksymets Alona Mykolaivna
Qualification Level: magister
Speciality: Heat and Power Engineering
Institute: Institute of Power Engineering and Control Systems
Mode of Study: part
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: Maksymets А.M., Rymar T.I. (supervisor). The operation efficiency increase of the turbogenerator cooling system of the PT-60-130/13 turbine at the Bila Tserkva TPP. Master’s thesis. – Lviv Polytechnic National University, Lviv, 2022. Extended abstract Today, the central part of electricity in Ukraine is produced at thermal and nuclear power plants, where turbogenerators work [1]. Most turbine units have already served their regulatory term, and some are on the verge of expiry due to insufficient financing from the energy industry. Under this mode of operation of electric machines, uniform loads in the electrical network are complicated, which is caused both by the overloading of generators (transition to emergency modes of operation due to the malfunction of generators at stations or an increase in the amount of consumed energy), and their shutdown (decrease in the amount of consumed energy ). The solution to this problem is partially modernizing existing units to increase their capacity and the step-by-step parallel replacement of the rest of the outdated turbogenerators with more powerful and lighter ones. In general, during modernization, the amount of copper in the winding is most often increased by reducing the thickness of the insulation (using new materials) and reducing the length of the stator and rotor cores, as well as trying to lighten the auxiliary units in the unit and improve the ventilation systems of electric machines [2-5]. Therefore, during modernization, the parameters of temperature and force loads on structural elements may change, which requires verification calculations. In most cases, simplified methods are used for calculating ventilation and thermal processes and the strength of the structure, where one- or two-dimensional problems are solved. As a result, the average values of the parameters in certain sections are obtained and compared with the values given in the regulatory documentation. In this case, possible calculation inaccuracies are compensated by increased reserve factors, which are selected based on the experience of operating electric machines. Study object – the turbogenerator cooling system of the РТ-60-130/13 turbine of Bilotserkivskaya CHРP. Scope of research – systematic approaches to solving the problems of calculation substantiation of increasing the maximum power of the turbogenerator in the case of air cooling due to internal cooling of the stator winding with compressed air. Goal of research: ensuring the efficient operation of the thermal and electrical parts of the РТ-60-130-13 turbine unit of Bilotserkivskaya СНPP, improving the cooling system for uninterrupted operation of the turbo unit. The master’s thesis examines the option of replacing the hydrogen-cooled turbogenerator, which has completed its service life, with a more efficient and economical air-cooled turbogenerator. The search for new solutions and technologies for increasing the cooling efficiency and improving the design of the air-cooled turbogenerator in the direction of increasing its unit power and reliable substantiation of new design solutions related to the thermal state of the active zone, operational and structural-technological properties of such turbogenerators was carried out. In the third section, the latest technologies of domestic and foreign companies to increase the efficiency of turbogenerators are considered: a multi-jet scheme of ventilation of a turbogenerator; U-shaped channels that provide adequate cooling of the active steel of the stator in the compartments of the stator cores. A study of the characteristics of the radial-axial air cooling system was conducted. The comparison and distribution of heat transfer coefficients show that in the radial sections of the ventilation tract, cooling is 1.5 times higher than with the U-shaped channel. The new cooling system has the following comparative advantages over the existing system. An increase in the total cooling surface in the toothed area. Addition of heat transfer coefficients in radial channels by 1.5-1.6 times. The coefficients of heat transfer in relatively short axial channels are quite high. The calculation of the maximum temperatures of the toothed zone was performed. The desired temperature excess is 17°C less than in the previous design. In the fourth chapter, the payback period for the РТ-60-130/13 turbine reconstruction is defined as 4.2 years. In the energy industry, this is a good indicator since, in the energy sector, the payback period is up to 5 years. Keywords: CHРP, turbogenerator, cooler, radial-axial air cooling system. References 1. Semerak, М. М., Sybota, А. V., Zheliak, V. І. (2013) Modeling of thermogasodynamic parameters of a hydrogen jet in case of depressurization of the turbogenerator body of an electric station. Visnyk of the Lviv State University of Life Safety. – № 7. – P. 225 – 229. 2. Kobzar, K. O., Tretiak, O. V., Shut, O. Yu., Poliienko, V. R., Hakal, P. H., Piatnytska, Ye. S. (2018) Development and implementation of promising methods of calculation and modeling in the design and operation of powerful turbogenerators and hydrogenerators for thermal power plants, nuclear power plants, hydroelectric power plants, gas power plants. Visnyk of NTU "KhPI". Collection of scientific papers. Ser. Electric machines and electromechanical energy conversion. Kharkiv, NTU "KhPI". № 5 (1281). P. 38 – 45. 3. Tretiak, O., Kobzar, K., Repetenko, M. (2018) The methodology for calculating of gas coolers for turbogenerators in three-dimensional setting. European Sciences review. Vol. 1, № 9 – 10. P. 119 – 123. 4. Kuzmin, V. V., Zozulin, Yu. 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