Static two-group excitation control system for hydrogenerator
Students Name: Tyryk Mykhailo
Qualification Level: master (ESP)
Speciality: Electrical Energetics, Electrical Engineering and Electromechanics
Institute: Institute of Power Engineering and Control Systems
Mode of Study: full
Academic Year: 2019-2020 н.р.
Language of Defence: ukrainian
Abstract: Purpose of work - the choice of excitation system for the Hydro Accumulative Power Plant Hydrogenator of Dnister, the choice of the system of automatic regulation of excitation and adjustment of its regulators, computer simulation of the main operating modes of the proposed excitation system, namely: the initial excitation of the hydro-generator without load, regulation of the hydro-generator load in the power system and short circuit in the power system. The object of research - synchronous hydrogenator with static excitation system. The subject t of research - operating modes of hydrogenator with static excitation system, synthesis of automatic excitation control system. In the master’s qualification work, there were analyzed the types of hydrogenators, their disadvantages and positive aspects. In particular, there were analyzed the hydrogenators used at the Hydro Accumulative Power Plant of Dnister, and there were also given the characteristics of a synchronous machine. In the master’s qualification work also various types of excitation systems of a hydrogenator, its negative and positive sides have been investigated. In the work the types of systems of automatic regulation of excitation were also investigated and mathematically automatic regulator of excitation was described and principal schemes to the execution system were given. Also, automatic regulators of excitation of strong action are considered and their structural schemes are given. As it is known, in the main modes of operation of synchronous generators are: start, automatic regulation of excitation on different parameters, excitation voltage boost at supply voltage deflection and at shock load applied to the shaft of generators, extinguishing the magnetic field, to create high-quality conditions for self-start and elimination of emergency condition, exactly for that in the master’s qualification work were also considered regulations using PI regulators, and their mathematical record is given. The main stage of the master’s qualification work was the choice of regulation of excitation of the hydrogenator and as a result of the conducted analysis for regulation of excitation of the hydrogenator thyristor system of excitation of direct action, which provides high speed regulation of excitation, so the peculiarity of the dual-group system of regulation of excitation is the presence of two sets of valves, which can work both jointly and separately, and as a result of which the use of such a system allows the thyristor system of regulation of excitation. In the master’s qualification work for regulation of generator output voltage was used proportional regulator with flexible feedback on the excitation voltage of the generator. The next stage of the master’s qualification work was to perform calculations of hydrogenator parameters, which were necessary to create a mathematical-computer and was also made by the calculations of the graph of angular characteristics of the synchronous machine, and the stability of the synchronous machine, which by calculations was from 0 ° -75 °. In the environment of MatLab Simulink the model of system of generation of the electric power with the hydrogenator and excitation system by means of which the system of automatic regulation is synthesized and the basic modes of operation are investigated, namely: computer modeling of a mode of initial excitation on idle run, computer modeling of a mode of change of loading, computer modeling of a mode of change of short circuit, also master’s qualification work separately is focused on influence of parameters of the regulator on static and dynamic.