인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
지원사업
학술연구/단체지원/교육 등 연구자 활동을 지속하도록 DBpia가 지원하고 있어요.
커뮤니티
연구자들이 자신의 연구와 전문성을 널리 알리고, 새로운 협력의 기회를 만들 수 있는 네트워킹 공간이에요.
초록·키워드
Grid-forming inverters (GFMs) can contribute to enhancing the voltage and frequency stability of power systems. However, small-signal instability accompanied by low-frequency oscillations may occur depending on grid strength and control parameters. This paper develops a state-space model and a dq-axis admittance model for a GFM inverter employing virtual synchronous generator (VSG) control. Based on these models, the small-signal stability of the multi-input multi-output (MIMO) system is analyzed using the generalized Nyquist criterion. The accuracy of the developed model is validated by comparing the admittance derived from the state-space model with that extracted from PSCAD simulations. It is also confirmed that the oscillation frequency of the dominant mode calculated from the state-space model agrees with that observed in the PSCAD active power response. In addition, eigenvalue trajectories associated with variations in the short-circuit ratio (SCR) and damping coefficient are analyzed, demonstrating that the stability margin tends to decrease as grid strength increases. To mitigate the deterioration of stability under strong-grid conditions, virtual impedance is applied, and the admittance characteristics, generalized Nyquist plots, and active power responses before and after its application are compared. The results demonstrate that virtual impedance improves the oscillation damping performance and small-signal stability of the GFM-VSG system under strong-grid conditions.
본문·목차
인공지능 문자 인식 모델을 통해 추출된 텍스트로, 일부 오타나 오류가 포함될 수 있으나 지속적으로 개선 중입니다.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.