2023 6th International Conference on Energy, Electrical and Power Engineering (CEEPE) Energy, Electrical and Power Engineering (CEEPE), 2023 6th International Conference on. :781-787 May, 2023
Subject
Power, Energy and Industry Applications Linear systems Analytical models Uncertainty Computational modeling Voltage Power system stability Stability analysis safe operation region (SOR) stability time-varying system operating point full operating space
The uncertainty of renewable energy generation makes the operating point of the grid-connected inverter (GCI) exhibits strong time-varying characteristic. This fact further causes the challenge that traditional stability analysis methods based on the linear time-invariant (LTI) model may be incompetent to characterize the dynamic properties of inverters under all operating conditions. To address this problem, this paper proposes a new stability analysis method for GCIs considering the time-varying characteristics of operating points. This method can describe the output limit of the GCI over its full operating space, which in turn facilitates the prediction of possible instability problems during its full operation process. First, the internal mechanism that the operating point affects system stability is explained. Then, the safe operation region (SOR) of GCI is accurately described considering the influence of the operating point. On this basis, the influence of several factors on the SOR is discussed, including filter impedance mismatch, line impedance variation, and grid voltage disturbance. Finally, the correctness of the proposed method is verified by simulation and experiment. The proposed method has wide application potential in engineering scenarios such as analyzing the operation limits of power electronic equipment, guiding converter design, and assisting power devices to play its extreme performance.