满足风电并网爬坡率标准的风储联合优化控制.docVIP

 Optimal Control of Wind/Storage System Satisfying Ramp Rate Limit in Grid Codes# WANG Ying, DAI Xianzhong, ZHANG Kaifeng** 5 10 15 20 25 30 35 (School of Automation, Southeast University, Nanjing, 210096) Abstract: Wind power ramp rate limit in grid codes must be satisfied when smoothing wind power fluctuations. A methodology is proposed in this paper that can satisfy the ramp rate requirement by using two means, i.e. energy storage system and wind power curtailment. Based on the ultra-short-term wind power prediction, a rolling optimization problem is established to maximize the total profit of wind/storage hybrid system. The proposed method is applied in a case with practical data from an actual wind/storage demonstration project in China and the results show the effectiveness of the method.) Key words: wind power generation, energy storage, power smoothing, ramp rate control 0 Introduction Wind energy has experienced phenomenal growth in recent years. As the wind power fluctuates, the integration of wind poses profound challenges to the operation of grid. Specifically, large changes of wind power within a short period of time are difficult for power system operators to manage. Studies conducted on the CAISO, PJM and ERCOT have shown that large ramps of wind power exist in each of these systems and sometimes lead to large wind ramping events [1]-[2]. For this reason, ramp rate requirements of wind power have been imposed by many grid codes [3]-[4] EltraElkraft, AESO, ERCOT, UK, etc.). In some other countries, such as Ireland and China, ramp rate over 10 min is also prescribed. The idea of using energy storage system to smooth the fluctuations of wind power can be found in [5]-[9]. An optimization problem is proposed to minimize the variance of wind/storage output [5]. Although this method reduces the output fluctuations, the results cannot assure to satisfy the ramp rate limit in grid codes. Different kinds of filters, such as low-pass filter, band-pass fil