基于EMD分解的混合储能辅助火电机组一次调频容量规划

Study on primary frequency modulation capacity planning of thermal power unit assisted by hybrid energy storage based on EMD decomposition

高新能源渗透率的新型电力系统更容易发生发电侧与用户侧的负荷失衡,从而造成电网频率波动,这对电网安全带来了巨大的挑战。提升发电侧主动调频支撑成为解决这一问题的关键。储能技术辅助调频主力的火电机组参与发电侧一次调频不仅可以提升电网安全性,也能降低机组磨损,提升机组运行的经济性。现存一次调频储能容量配置方法比较单一。因此,本文提出了一种基于EMD分解的混合储能辅助火电机组一次调频容量规划方法。使用EMD对储能的目标功率进行处理,并将处理后的IMF分量进行重构,从而确定混合储能的功率与能量配额,以归一化成本为最优目标,完成储能系统规划,弥补了现存研究未充分考虑功率高低频响应导致的储能配置方案不合理,不能充分利用不同形式储能特性造成的储能投资成本高、储能系统收益低、调频效果不理想等缺点。并以宿迁660 MW机组为一次调频算例验证了本文方法的可行性与经济性。研究结果可以为参与一次调频的火电机组储能规划提供一定技术参考。

The new power grids with the high penetration of new energies are more prone to load imbalance between the generation side and the user side,resulting in fluctuations in the grid frequency,which brings great challenges to frequency safety.Improving the active frequency modulation support is an effective method for the generation side.The energy storage technology,which assists the thermal power units participating in the primary frequency regulation,can not only improve the safety of power grids,but can also reduce the wear of the units and for more economic unit operations.The existing configuration method of the primary frequency modulation energy storage capacity is relatively simple.Hence,a configuration method is proposed for the hybrid energy storage system to assist the thermal power frequency modulation,based on the empirical mode decomposition(EMD).By adopting the EMD,the hybrid energy storage system power obtained by the target power is processed,and the modal components obtained from the EMD decomposition are reconstructed to determine the energy storage power allocation.Moreover,the power and capacity planning is conducted,and the optimal optimization scheme of the hybrid energy storage system is determined by taking the whole life cycle cost of the hybrid energy storage as the optimization objective.Our proposed method makes up for the unreasonable energy storage configuration scheme without fully considering the high-and low-frequency response of power unit,the high investment cost of energy storage caused by the inability to fully utilize different forms of energy storage characteristics,the low income of energy storage system,and the unsatisfactory frequency modulation effect.Finally,the effectiveness and economic aspects of the above planning methods are verified using a specific example in Suqian.This study can provide some technical references for the planning of hybrid energy storage in the frequency modulation of thermal power units.