Flexible Power Regulation Control Strategy for Gravity Energy Storage System

Driven by the “carbon neutrality and carbon peaking” goal, gravity energy storage has become an important support technology for new power systems due to its advantages of environmental protection, no self-discharge and flexible layout. Aiming at the power fluctuation problem caused by mass block scheduling in the charging and discharging process of gravity energy storage and the active/reactive power response demand of the grid, this study takes the ramp gravity energy storage as the object, and respectively constructes the simulation model of the gravity energy storage system including two types of motors (electrically excited synchronous motor and doubly-fed motor) and three typical control strategies (vector control, direct power control and sliding mode control). The corresponding mathematical model and power coordination control strategy are established. The simulation results show that the electrically excited synchronous motor system with sliding mode control has the best dynamic response and steady-state accuracy in terms of active/reactive power regulation performance. The doubly-fed motor combined with sliding mode direct power control strategy also shows good adjustment ability and robustness.