海上风电水下压缩空气储能系统运行及变工况分析

Operation and Varying Load Analysis of Offshore Wind-Underwater Compressed Air Energy Storage System

水下压缩空气储能是一种能够利用水下静压储存压缩空气的技术,该技术与海上风电相结合,可以大规模储存具有波动性、间歇性的海上风电,从而使电力输出满足用电负荷需求。因此,建立了一个海上风力发电与水下压缩空气储能系统相结合的物理模型。首先,在充-储-释理想运行模式仿真下,确定了在储气压力约束下的系统最优额定工况;然后,为了扩大储能系统变工况运行范围,优化了水下压缩空气储能系统的变工况空气流量和导热油流量;最后,在真实海上风机发电和海岛用电负荷数据下,建立了一个由3 MW×2海上风电与3 MW/45MWh水下压缩空气储能组成的系统,并模拟真实海上风电和用电负荷运行模式进行了运行仿真。结果显示,在充-储-释理想运行模式下,系统可在10%~120%工况范围内运行,且系统循环效率范围为48.1%~58.4%;在模拟真实海上风电和用电负荷运行模式下,系统循环效率为53.7%,并且弃风率减少至0.58%,负荷满足率提升至99.57%。

Underwater compressed air energy storage(UWCAES) is a large-scale energy storage technology that can take advantage of hydro-static pressure in the deep ocean.Integrating the UWCAES into offshore wind power generation can store fluctuate and intermittent wind energy,so that the output power can be smoothed to satisfy the user electricity demand.In this paper,the physical model of the wind power generation and UWCAES integrated system has been built.Based on this model,the optimal nominal working condition has been determined under an ideal charge-store-discharge operation mode with the air storage pressure constraint.Then,in order to expand the working condition range,the air and thermal oil flow rate of UWCAES have been optimized under the variable working condition.Finally,an integrated system of a 3 MW×2 wind power and a 3 MW/45 MWh UWCAES have been tested under the real wind power and the user electricity demand data.Results show that,under the ideal charge-store-discharge operation mode,the integrated system can work within the range of 10% to 120%,and the round-trip efficiency is 48.1%~58.4%.Besides,the operation simulation under the real wind power and user load data also shows that,the integrated system round-trip efficiency is 53.7%,and the wind curtailment rate is declined to 0.58% and the load satisfaction ratio is promoted to 99.57%.