Development of a Grid Adaptability Evaluation Method for Systems with Renewable Energy Connected to Weakly-Synchronized Sending-End DC Power Grid

With the increasing proportion of power electronic equipment, the inertia of power system continues to decrease, and the stability of synchronous power grid based on rotor operation equation has changed greatly. For the systems with renewable energy connected to weakly-synchronized sending-end DC power grid, due to overvoltage, oscillation and other problems, the operation risks of power grid are increased. At present, the existing monitoring methods are not able to obtain the in-depth information of grid connection adaptability and support capacity. A new grid adaptability evaluation method considering the SCADA data is proposed. According to the application scenarios, a multi-level architecture is designed, which carries out evaluation index calculation at the station-level for high real-time requirements, and transfers the results to superior-level for comprehensive analysis. The method can be popularized and applied to the grid operation monitoring of renewable energy, which may plays an important role in improving the stability of weakly-synchronized sending-end DC power grid.