Control Strategy and Simulation Analysis of Direct-Drive Fan and Weak Power Grid based on RTDS

As renewable energy becomes more prevalent in power systems, direct-drive wind turbines, a type of clean energy, are gaining prominence globally. However, their interconnection to the grid presents challenges due to the unpredictability of their power output, especially in weak grid environments. This paper introduces a control strategy for direct-drive wind turbines and weak grids using a Real-Time Digital Simulator (RTDS). The strategy aims to understand the oscillation issues in these systems. Simulations show that with higher series inductance and weaker grids, the oscillation frequency decreases. Higher wind speeds lead to lower oscillation frequencies, suggesting that lower wind speeds are more likely to cause oscillations. When multiple wind turbines are simulated, the number of turbines increases, leading to higher oscillation frequencies, indicating that more turbines are more prone to oscillations.