Abstract:

In the modern power system with high penetration of renewable power generation, giving full play to the potential of coordinative and complementary operations between different power generation sources and different energy storage equipments, can alleviate the huge stress on the system's power and electricity balance caused by the volatility of new energy output. This paper proposes an optimal scheduling strategy for power and electricity balance considering multi-energy complementation, such that multi-energy dispatch is coordinated under different time scales and hence the overall operating performance of the system can be improved. First, according to the seasonal and short-term fluctuation characteristics of new energy output, by taking into account the medium and long-term electricity balance as well as short-term power balance, the multi-time scale double-layer optimal scheduling system model is established. Then, through the optimization of the charging and discharging strategy of the hybrid energy storage system, the operation of multiple energy storages is coordinated efficiently and the economic benefit of system operation can be boosted. Finally, case studies are performed to verify the effectiveness of the proposed method on the modified IEEE-RTS 1979 system model. The results indicate that the energy complementation of different time scales and the coordination of different energy storage equipment can be applied to improve the economic benefits of the system while maintaining system power balance.

Key words: power balance, hybrid energy storage system, multiple time scales, multi-energy complementation, optimal dispatch