Nikola Tesla Institute
Ilija Klasnić
Excitation Systems for Motor-Generators in the Bajina Bašta Pumped-Storage Hydropower Plant
ABSTRACT
The Bajina Bašta hydropower plant and the Bajina Bašta pumped-storage hydropower plant in Perućac are the largest hydroelectric facility built on the Drina River. The Bajina Bašta pumped-storage hydropower plant is of great importance to the Serbian power system due to its ability to operate in both generator and motor modes, which increases system flexibility in terms of production and consumption management. Periods of low electricity consumption are used to fill the upper reservoir by operating the plant in motor mode. When the system requires additional energy, the units switch to the opposite mode, and by releasing water from the higher-altitude reservoir, the turbines are driven to generate electricity. Also, due to its ability to quickly start and quickly change the operating mode from generator to motor and vice versa, this plant can quickly respond to system disturbances and replace any other unit in the Elektroprivreda Srbije system. Therefore, the revitalization of the Bajina Bašta pumped-storage hydropower plant, which should extend the lifespan of the units by several decades, is of great importance to the power system. In 2024, the first unit was revitalized, while the revitalization of the second unit is planned for 2025. The Nikola Tesla Electrical Engineering Institute participated in the revitalization by replacing the excitation systems. Within the energy part of the excitation system, components with top performance were installed: excitation transformers, switches, thyristor bridges, demagnetization equipment, etc. The basis of the control part of the excitation system consists of certified INTROL excitation regulators, within which sequential automats for all operating modes of the units were implemented: generator mode, motor mode, synchronous start, electric braking, and testing for testing purposes. INTROL regulators enable various control modes: automatic stator voltage regulation, automatic reactive power regulation, and automatic power factor regulation, along with which limiter functions and a power system stabilizer were implemented. Thyristor bridges and excitation regulators are implemented redundantly in a 1+1 configuration. After installation and connection, the excitation system was adjusted and tested, which showed good system performance, enabling reliable and stable operation of the units in all operating modes with automatic limitation of operation within the limits defined by the operating diagram.
Keywords: Excitation system, Motor, Generator, Revitalization
Biography of the presenter
Ilija Klasnić completed his bachelor studies in 2012 at the Faculty of Electrical Engineering, University of Belgrade, Department of Power Converters and Drives. He completed master academic studies in 2013 and successfully defended his doctoral dissertation titled “Estimation and Prediction of the Hydrogenerator Rotor Thermal Capability and Influence on the Reactive Power Capabilities” on September 29th, 2023, at the Faculty of Electrical Engineering, University of Belgrade.
Since February 2013, he has been employed at the Nikola Tesla Institute of Electrical Engineering in Belgrade, where he has been engaged in the design and commissioning of excitation systems of synchronous generators, site acceptance and performance testing of rotating electrical machines, testing of power converters, consulting services in the field of power engineering, and thermal modeling of synchronous generators.
He is the author or co-author of several papers published in journals with an impact factor and at national and international conferences. He received the award for the best paper by a young researcher in the Power Engineering section at the 58th ETRAN Conference.
He serves as the secretary of the Study Committee STK A1 Rotating Electrical Machines within CIGRE Serbia, as well as a regular member of the STK A1 Rotating Electrical Machines within International CIGRE.
