Research on the design and simulation of grid-connected system of vertical gravity energy storage

Due to the characteristics of the body's movement, the output power of the gravity energy storage system is unstable. When the system is connected to the grid, smooth control of the output power is required. To this end, this paper proposes a control scheme that uses multiple units for joint power generation and complements the output power. The system operation parameters are optimized through an optimization algorithm to achieve power smoothing. The optimized gravity energy storage system can output stable power generation and can be equivalent to a controlled current source in grid-connected systems. Based on this, a corresponding gravity energy storage grid-connected system was designed, and the converter adopted a voltage-oriented vector control strategy for grid connection control. Subsequently, grid-connected system simulation and short-circuit fault simulation experiments were carried out. The simulation results show that the output power of the optimized gravity energy storage system is stable, and the minimum power fluctuation rate can reach 6.7%. The designed grid-connected system has a fast response speed and good steady-state characteristics. It can return to the original value after a sudden change of 0.4 s in the system input, so as to achieve the stable grid connection of the gravity energy storage system.