A Novel Two-layer Control Strategy for LHSS - SMES Participate in Power Auxiliary Service

The liquid hydrogen Storage System (LHSS) combined superconducting magnetic energy storage (SMES) have both features of power-type and energy-type energy storage, and is capable of providing power grid auxiliary services. This paper analyzes basic structure of LHSS combined SMES. Requirements for participating in grid auxiliary services and the VSG control strategy are also analyzed in this paper. A novel two layer control strategy which focus on upper layer energy control and lower layer power control is proposed in this paper. A study case is given to verify the effectiveness of the proposed control strategy.