Reliability analysis of centralized protection system considering the impact of messages under multi-operating states

The operation of centralized protection system highly depends on reliable communication messages. A method was proposed to quantitatively evaluate reliability of messages under the redundancy check mechanism in smart substation. Subsequently, corresponding reliability models were established based on detailed analysis of different centralized protection strategies under normal and fault states of power grids, as well as message loss and message error. Finally, contrastive analysis was carried out to demonstrate the impact of messages on centralized and distributed protection systems. Results indicate that the influence of communication messages on the reliability of centralized protection systems is lower.