Research on Collaborative Control and Operating Characteristics of Subsystems in Gravity Compressed Air Energy Storage

Gravity compressed air energy storage, as an energy type energy storage system, is a novel form of energy storage system that transfers mechanical energy from solid heavy energy storage media to thermal energy from compressed gas and electrical energy. It combines the versatility of gravity energy storage with the high energy density of compressed air energy storage technology. Aiming at the gravity compressed air energy storage system, this paper proposes a gravity compressed air energy storage control strategy to achieve the switching between the two operating states of releasing power and absorbing power in the energy storage system, as well as accurate tracking of the power demand on the grid side through the coordinated control of the two. First, based on the architecture of the hybrid energy storage system constituted of gravity compressed air energy storage, a gravity compressed air energy storage simulation model was constructed using the PSCAD/EMTDC platform. Second, a control method was provided for gravity compressed air energy storage, in which the gravity energy storage portion reacts to the power demand command issued by the grid side, and the compressed air energy storage part responds to the power demand command absorbed by the grid side. Finally, the effectiveness of the suggested technique was confirmed using the developed gravity compressed air energy storage simulation model, and the energy storage system's operating characteristics were investigated.