A novel transient stability index based on grid reduction method to analyze power systems with high penetration of non-synchronous generation

The integration process of renewable energy sources brought challenges for system operators around the world. The new technologies – especially wind and solar generation – have different characteristics than synchronous generators. Due to the changes in the generation mix, grid calculation methods need to be reviewed to cope with the system models. The scope if this work is the generator-driven stability phenomena. A new classification is proposed to distinguish stability categories based on the system’s generation mix. This highlights the need for novel calculation methods in stability calculations due to major changes in the physical properties of the input data. Then this paper proposes a novel transient stability index (re-revised transient stability index), which is capable of quantitatively describe the transient stability of the system when the generation mix contains high amounts of non-synchronous generators. The method was tested on the IEEE 9 – BUS model and the Hungarian power grid model to provide results for comparison and practical applications as well. Based on the simulation results, the method showed that non-synchronous generation lowers the critical clearing time of power systems.