Shevchenko V. Scientific and Technical Principles of Maintaining the Competitiveness of Turbogenerators and Ensuring their Efficiency During Long-term Operation

Technical and technological measures to improve the energy efficiency of new turbogenerators and turbogenerators that have been in operation for a long time, by scientifically substantiating the choice of design parameters and manufacturing technologies, developing diagnostic and repair methodologies to ensure further operation and sustainable operation of the modern power grid. technical competitiveness of new turbogenerators on the world market are developed in the work. The most probable development scenario was established to confirm the prospects of carrying out work on the turbogenerators study and to determine promising directions for the creation of new and modernization of already operating generators using the theory of cyclic development. The subject of research was electromagnetic, mechanical and thermal processes in turbogenerators. The study object was new turbogenerators and turbogenerators that have been operating for a long time at TPP and NPP units, their characteristics and the choice of directions for improvement, taking into account the peculiarities of modern operating conditions. Techniques for the modernization of turbogenerators and coolers with the condition of increasing power without changing the weight and dimensions and replacing the cooling medium (hydrogen with air) were proposed. For the first time, the thermal and mechanical condition of turbogenerators modernized elements was determined by simulation; the influence of the rate of load change on the degree of the deformation winding rods and the insulation is established; the influence of the scheme of assembly of the stator cores, the influence of the quality of core crimping on the operational reliability and durability of turbogenerators, which improves the quality of design. The need to take into account the state of turbogenerators when determining the sequence of their inclusion in the power system is proven in the work, and also found that it is advisable to maintain the nominal parameters of the Ukrainian power system by turbogenerators with a capacity of 200-300 MW of thermal power plants. The use of NPP turbogenerators for this is unacceptable. An algorithm for calculating the maximum permissible wear of turbogenerator elements is proposed and a system for registering their actual state in on-line mode is proposed. Methods of diagnostics of turbogenerators and their cooling systems defects are offered, and also receptions of elimination of defects on blocks of stations are developed; the influence of the arrangement of heat exchangers of turbogenerators and the number of strokes of cooling gas on thermal stresses, distribution of the maximum temperature and its difference on a surface of tubes of heat exchangers is established. The methodology for calculating the forces acting between the sheets of the turbogenerator’s stators laminated cores has been developed. It was found that the action of these forces can be one of the reasons for the destruction of the cores not only in the end zones, but also in the middle of the generator. Assessment of the turbogenerator and its elements technical condition was carried out in order to determine the possibility of their further operation and to establish the amount of necessary repairs, to establish the possibility of rehabilitation or complete replacement. In the development of new turbogenerators focused on world standards in the field of turbogenerators.