Dynamics Islanding Control for Power Grid With High Penetration of Renewable Energy

Out-of-step (OOS) oscillation is a key link in the power system outage evolution. Precise islanding control can prevent system outages. Renewable energy is connected to the power grid through transverter. From a system construction perspective, it can be regarded as grid-following sources. A large number of inverters lead to more dynamic instability characteristics in the power system, affecting the reliability of existing island control. In this article, the model of oscillation in system with renewable energy is simplified based on the control objective of the converter. The change in OOS oscillation characteristics is analyzed, caused by energy fluctuations. The results show that energy fluctuations during OOS oscillations may affect rotor angle stability and cause the center of oscillation to migrate dynamically over a wide range. This article proposes an islanding control method based on power flow. It only requires dispatchers to obtain power flow information to accurately predict the trend of system instability and dynamically track the center of oscillation. The judgment results can serve as criteria for dealing with the problem of when and where to split the power system. The proposed method has been tested on the IEEE testing system.