| Title |
A Study on Speed Control of Variable Frequency Transformer for Suppressing Power System Low Frequency Oscillation |
| Authors |
안병현(Byeong-Hyeon An) ; 박재덕(Jae-Deok Park) ; 김태훈(Tae-Hun Kim) ; 채준수(Jun-Soo Che) ; 표수한(Su-Han Pyo) ; 박태식(Tae-Sik Park) |
| DOI |
https://doi.org/10.5370/KIEE.2022.71.5.675 |
| Keywords |
VFT(Variable Frequency Transformer); LFO(Low frequency Oscillation); Grid-interConnection; PSS(Power System Stabilizer); FLC(Frequency Limit Control); FACTs(Flexible AC Transmission system); DC grid |
| Abstract |
Recently, an energy transition is taking place around the world in the direction of increasing the proportion of renewable energy in order to reduce carbon emission. Accordingly, the problem of unbalanced distribution of power resources and loads has been raised, and the studies on asynchronous grid connection and AC-DC hybrid grid connection based on long distance large capacity power transmission technologies such as HVDC and HVAC are in the spotlight. Such a complex system structure may threaten the stability of the system so consideration of system operation is essential. In particular, Low Frequency Oscillation (LFO) is considered to be a factor that adversely affects power system stability, such as a torsion of a generator shaft or a decrease in generator output. LFO occurring under certain conditions in the power system are characterized by slow attenuation or gradually amplification. As a solution to suppress such LFO, there are PSS (Power System Stabilizer) of a generator system, FLC (Frequency Limit Control) of DC power system, and FACTs (Flexible AC Transmission system) facilities. However, these conventional studies have problems such as control difficulties and high investment costs. In this paper, a LFO suppression method using Variable Frequency |