Analysis tools for assessing the impact of wind power on weak grids

The integration of inherently variable wind generation into weak grids, particularly sub-transmission networks that are characterized by low X/R ratios, affects bus voltages, regulating devices and line flows. The meshed structure of these networks adds to the complexity, especially when wind generation is distributed across multiple nodes. This paper considers a range of techniques for analyzing the impact of wind variability on weak grids. Sensitivity analysis, based on the power-flow Jacobian, is used to highlight the sections of the system that are most severely affected by wind-power variations. A continuation power flow is used to determine parameter changes that reduce the impact of wind-power variability. It is also used to explore interactions between multiple wind-farms. Two optimization problems have been formulated to identify line segments that are most vulnerable to congestion as wind-power varies. The DC optimization is computationally more efficient, whereas the AC sensitivity-based optimization provides greater accuracy.