Protection Security Assessment with Guiding Optimization Criteria based on Stability Indices

Major disturbances in recent years have shown that protection systems play an important role in the actual course of events and that improper behavior can have a strong negative impact. Regular review of protection settings and adaptation to new conditions is therefore an important task in modern power grids to ensure overall system security. Changing grid structures, volatile feeders, more dynamic loads and higher loading rates are the challenges that need to be met.This paper presents an innovative protection security assessment system that has been designed to provide sound feedback on system stability in order to effectively guide an optimization method. This allows all setting values of all protection devices of a system-wide grid to be checked simultaneously, adapted to new situations and beeing optimized. For this purpose, the system uses new indices, which are introduced, described in detail and demonstrated by means of a case study. Finally, a comparison with classical protection criteria is made.