Modeling of wind power plant collector system in power system planning stability studies

The paper discusses modeling of the collector system of a wind power plant in power system planning stability studies. Numerical experiments performed for a variety of wind turbine generator (WTG) devices use their vendor-specific stability models and are run on large power system databases assuming realistic contingency scenarios. Simulations have provided evidence that collector system aggregation can affect fault ride through capability assessment. In particular, the assessment of percentage of the total plant capacity remaining online post-contingency can change; the use of a single WTG equivalent does not necessarily ensure the worst case scenario. Due to concerns about the trustworthiness of some vendor-specific WTG stability models, further analyses based on EMTP-type simulation tools are needed. Meanwhile, it is recommended that a planning stability study include sensitivity analysis to justify the level of collector aggregation.