The new hybrid storage technology developed by Chinese researchers can achieve an efficiency of over 80% and can be applied in distribution and transmission networks. The proposed combination is said to be able to offer the advantages of gravity energy storage and power-based storage systems in one solution.
The researchers named the proposed combination a hybrid-solid gravity energy storage system (HGES) and said this technology could find applications in both districttransmission networks, while resolving By avoiding GES technical problems frequent starting and stopping of the motor, which can cause losses and significant variations in output power. “Various possible system design designs for the proposed HGES have been investigated”, corresponding author of the study, Wenxuan Tongtold pv magazine.
In the proposed system configuration, the GES unit is connected to a power-based storage module. A GES unit is used to draw excess power from the grid or release power when grid demand exceeds production, while a power-based module provides rated power to compensate for the variation in active power operation of the GES system.
The composition of HGES depends type of motor used, electric drives, network access method and power-based energy storage location. “From the point of view of the structural composition of the system, HGES can be divided into mechanical systems, motors, electrical drive systems, grid access systems, and power-based energy storage systems,” the researchers explained.
They also explained that the proper operation of the HGES system is highly dependent power electronics control, noting that in different situations, different control strategies should be applied to achieve the best integrated control effect. In addition, they said, control strategies should also be implemented one type of energy storage system and hybrid energy storage system level.
The academics ran a series of simulations Through Simulink (MATLAB) and found that the proposed system can meet their theoretical expectationsmeasures. “The power-based energy storage of the hybrid gravity storage system can well suppress the inherent power fluctuation problem of GES under the rectangular compensation strategy,” they emphasized. “The response speed of HGES has improved by 1-2 orders of magnitude compared to a single GES system.”
In addition, they claim that the system can achieve an efficiency of over 80 percent, especially if used in distribution and transmission networks. “That’s the ideal energy storage system without obvious performance disadvantages and will be due Thu offer critical technical support for developing renewable energy power systems,” they concluded.
Their findings are presented in the journal “Structure and control strategies of a hybrid solid gravity energy storage system”, published in the journal Journal of Energy Storage. The research team consists of researchers from North China Electric Power University and State Grid Smart Grid Research Institute Co., Ltd.