Innovative strategies for protection security assessment

Protection security assessment of power grids is getting an important task in the course of a decarbonized power generation and a competitive energy business. The analysis of past blackouts studied by the North American Electric Reliability Council (NERC) shows that protection relays are involved in about 75% of all major disturbances. Protection security assessment can be investigated under two different aspects: on the one hand the behavior regarding selectivity, speed and sensitivity and on the other hand the behavior regarding the response on dynamic network phenomena as voltage stability and transient stability. This paper is focused on the protection response on dynamic network phenomena and presents innovative strategies for this investigation aspect. Applicable protection models and the simulation environment based on PSS^®NETOMAC will be described. Case studies on real networks show the way of investigation and the achieved improvement of dynamic protection security based on the applied innovative strategies.