Rational Mode Parameters of Power Units Operating in Modern Energy Market Conditions

DOI https://doi.org/10.15407/pmach2024.01.035
Journal Journal of Mechanical Engineering – Problemy Mashynobuduvannia
Publisher Anatolii Pidhornyi Institute for Mechanical Engineering Problems
of National Academy of Science of Ukraine
ISSN  2709-2984 (Print), 2709-2992 (Online)
Issue Vol. 27, no. 1, 2024 (March)
Pages 35-45
Cited by J. of Mech. Eng., 2024, vol. 27, no. 1, pp. 35-45



Anatolii O. Tarelin, Anatolii Pidhornyi Institute of Mechanical Engineering Problems of NAS of Ukraine (2/10, Pozharskyi str., Kharkiv, 61046, Ukraine), e-mail: tarelin@ipmach.kharkov.ua, ORCID: 0000-0001-7160-5726



The paper analyzes the operation of condensing and heating turbines in modern energy market conditions with an assessment of the impact of operating parameters of live and secondary steam on economic indicators. It has been shown that when operating at variable loads, the most effective in terms of high-pressure turbines is a rational reduction in the initial pressure ps (sliding pressure), which leads to an increase in thermal efficiency by 1-1.5%. The experimental results of a study of the vacuum effect in the condenser on fuel consumption are presented in the paper as well. Using a specific example of the K-320-26.5 turbine unit, the need for a rational choice of cooling water flow in winter season to ensure optimal vacuum is shown. The issue of choosing a rational steam reheat temperature tr is examined in more detail. It has been established that one of the main reasons for the decrease in the efficiency of turbine units when operating in variable modes is the irrational use of the reheat temperature and the heat of phase transition in the flow part of the low pressure cylinder. The physical explanation of these processes in the turbine as tr decreases is given in detail. It has been shown that, as a result of analyzing the operation of turbine units of various capacities, a rational choice of reheat temperature (reducing tr by 10-20 °C) increases thermal efficiency by 1-2 %, and turbine efficiency – by 0.4-1.0 %. It is recommended to consider the pressure of the hot steam of the high pressure cylinder (рs), the pressure in the condenser (рc=f(tcirc.water)), as well as the reheating temperature tr, which altogether leads to a reduction in heat consumption by 2.5-3.5 % as rational parameters of steam when operating in variable modes. In order to increase the economic efficiency of the operation of turbine units of TPPs and CPPs at reduced loads, it is recommended to revise the regulatory documentation on the current amendments for changes in the reheat temperature. It is stated that with strict adherence to the recommendations discussed above, fuel savings at TTPs and CHPs in Ukraine can amount to 250–300 thousand tons of coal per year.


Keywords: steam turbine, variable loads, mode parameters, fuel consumption, efficiency.


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Received 21 November 2023

Published 30 March 2024