Research on Coordinated Reactive Power and Voltage Control Strategy for Regional Power Grids with High Penetration of Renewable Energy

The large-scale integration of renewable energy brings a great challenge to the voltage stability and reactive power balance of power grids. Unpredictable, intermittent, and irregular renewable energy sources can amplify the voltage fluctuations greatly. Thus the problem of power surplus emerges more frequently, leading to a more difficult control task. For renewable energy power plants in certain locations, it is beneficial to make use of the seasonal information and the pattern of power generation during the day or night. Meanwhile, the utilization of the traditional Automatic Voltage Control (AVC) and the coordination of the reactive power resources among different power plants can help to maintain the reactive power balance and the voltage stability in the regional power grids. Therefore, this work establishes a reactive power and voltage distribution model for the renewable energy power plants. Furthermore, based on this model, it proposes a coordinated control strategy for reactive power and voltage, by taking into account the coordination of various time scales as well as multiple reactive power resources. It has been shown to achieve a more stable control for reactive power and voltage in regional power grids. The results are validated via comprehensive simulation studies.