Analysis of operating conditions of a 1,060 MW TPP with 4х100+3х220 MW units connected to 110kV and 220 kV power systems
Students Name: Okhota Serhii Rostyslavovych
Qualification Level: magister
Speciality: Electrical Energetics, Electrical Engineering and Electromechanics
Institute: Institute of Power Engineering and Control Systems
Mode of Study: full
Academic Year: 2023-2024 н.р.
Language of Defence: ukrainian
Abstract: As of January 2022, several key aspects of energy development in Ukraine were as follows: Diversification of energy sources: Ukraine tried to reduce its dependence on imported natural gas from Russia. This included increasing the use of renewable energy sources such as wind and solar power. Energy efficiency: The government worked on programs and measures to improve energy efficiency in various sectors of the economy. This included the modernization of the housing stock, the introduction of energy-saving technologies in industry and other measures. Expanding the use of renewable energy sources: Wind power and solar energy have received more attention and investment to increase the share of renewable sources in electricity production. Energy sector reform: Ukraine continued to implement structural and institutional reforms in the energy sector to improve its efficiency and competitiveness. Implementation of European Union legislation: Ukraine actively cooperated with the European Union and implemented standards and norms common to the EU to address issues related to energy security and sustainable development. Fighting corruption: The government has taken steps to fight corruption in the energy sector to ensure a more transparent and efficient allocation of resources. At the moment, the direction of Ukraine’s development has shifted somewhat in the direction of protecting the existing energy system from the Russian invasion. The research object is a condensing power plant with a capacity of 1060 MW with 3x220+4x100 MW units. The subject of the research is established and post-accident modes of operation of the power plant. The purpose of the work is to analyze the results of calculating the stable and post-emergency modes of operation of the power plant in relation to the carrying capacity of overhead lines, their overloads and forming a conclusion about the possibility of implementing the developed condensation power plant [3][4]. The work analyzed the results of the calculation of the stable and post-emergency modes of operation of the power plant in relation to the carrying capacity of overhead lines, their overloads, and concluded about the possibility of implementing the developed condensing power plant. The following conclusions were made in the work: 1. Calculated power flows through the windings of block transformers and the communication autotransformer of the adopted version of the structural scheme of the 1060 MW KES with 3x220+4x100 MW blocks. 2. According to the calculated power flows for the 220 MW block connected to the 220 kV RP, a block transformer of the TDC type -250000/220 was selected. 3. Based on the estimated power flows for the connection between the 220 kV RP and 110 kV RP, a communication autotransformer was selected in the form of a group of three autotransformers ATDCTN -125000/220/110 4. For RP 220 kV, a scheme with two non-sectioned working and bypass bus systems with one switch per circuit, as well as bypass and bus connecting switches, was selected. The 220 kV substation is connected to power system No. 1 by seven overhead lines. 5. For RP 110 kV, a scheme with two non-sectioned working and bypass bus systems with one switch per circuit, as well as bypass and bus connecting switches, was selected. The 110 kV substation is connected to power system No. 2 by four overhead lines. 6. According to the maximum self-demand capacity of the block of 220 MW, the self-demand working transformer TRDNS-25000/35 was selected. 7. According to the maximum self-demand capacity of the block of 100 MW, the TDNS-16000/35 self-demand working transformer was selected. 8. One reserve transformer of own needs TRDN-32000/110 was selected for the backup of the KES self-demand system. 9. For 220 kV overhead lines, the AS-300 wire is selected. 10. For 110 kV overhead lines, the AC-240 wire is selected. 11. A simplified main diagram of electrical connections of the CHP was developed. 12. An alternate scheme for calculating the short-circuit currents of the power plant has been developed. 13. Defined parameters of the elements of the substitute scheme. 14. Calculation of short-circuit currents at five calculation points. 15. For each calculation point, the value of the overtransient short-circuit current at the moment of the short-circuit, its periodic and aperiodic component, the shock current of the short-circuit and the thermal impulse of the short-circuit are determined. 16. According to the results of the calculation of short-circuit currents, switches, disconnectors, current and voltage measuring transformers and current-conducting parts for 220 and 110 kV distribution devices of the power plant were selected. 17. According to the results of the calculation of short-circuit currents, the switches, disconnectors and current conductors of the 220 and 100 MW generators were selected. In the "Dakar" program complex, a power plant scheme was created for calculations. The following operating modes of the power plant for maximum and minimum load were calculated: • Maximum • Minimal • Post-emergency (shutdown of the 220 kV line) • Post-emergency (shutdown of the 110 kV line) • Post-emergency (turning off the generator connected to RP-110 kV) Under established operating modes, all parameters of the mode (currents in the lines, generation power) are within normal limits.