Dynamic model of a storage system with real-time simulation for power system reliability

The paper deals with the upgrading of the primary distribution networks applying the smart grid strategies. In particular, a new research field is devoted to the application of storage systems for the power quality improvement and the better exploitation of renewable sources. In this context, this work proposes the use of a storage based on lithium-ion batteries for the black start and island operation of a portion of the medium voltage network. The innovation of the idea proposed is related to a soft start of the system that reduces transient overvoltages and transient inrush current components in order to reduce the stress of the system and allow the supply in island through direct current/alternating current converters. Simulations carried out on a dedicated model implemented in real-time digital simulator are reported and analyzed. These tests are the basis for a full-scale prototype installation of the storage in a real Italian network as a part of a big project founded by the Italian Energy Authority.