摘要
针对独立微电网运行中存在的频率波动与新能源利用率不高的问题,该文提出一种风机和储能装置协同参与调频的新型功率柔性分配策略。首先,分析多种分布式电源在独立微电网中的运行及控制方式;其次,建立独立微电网中风机和储能装置联合参与调频的状态空间模型;然后,以频率偏差最小和能源利用率最高为指标构建滚动时域内的优化目标函数,并根据频率变化实时调整目标函数中风机和储能出力项的权重以优化各自出力。此外,所提策略能够参考风速和储能装置荷电状态的时变特性,在每个时间断面柔性调整约束条件的边界,提高其安全运行水平;最后,基于Matlab/Simulink仿真平台搭建独立微电网模型,并在多种工况下进行仿真研究,仿真结果表明,所提策略在满足风机与储能安全运行的前提下,能实现独立微电网频率控制的同时优化风机和储能装置的有功出力,降低弃风率,达到能量高效利用的目标,并且具有对模型参数依赖度低的特点,鲁棒性较好。
Aiming at the issue of frequency fluctuations and low utilization of new energy in isolated microgrid operation, a flexible power distribution strategy with wind turbine generator(WTG)and energy storage(ES) equipment for frequency regulation is proposed in this paper. Firstly, the operating characteristics and corresponding control modes of various distributed generations in isolated microgrid are analyzed. Secondly, the state space model of isolated microgrid with WTG and ES participating in frequency regulation is established. Then, the optimized objective function in the rolling time domain is constructed with the goal of minimizing frequency deviation and maximizing energy utilization rate. And according to the frequency variation, the weight coefficients of the WTG and ES output power item in the objective function are adjusted in real time. Furthermore, the proposed strategy can flexibly adjust the boundary of the constraint conditions at each time section according to the timevarying characteristics of the wind speed and the state of charge(SOC) of ES, which can improve their safe operation level. Finally, the isolated microgrid model is built in MATLAB/Simulink platform, and the proposed control strategy is verified under different working cases. Simulation results show that,under the premise of satisfying the safety operation, the proposed strategy can realize isolated microgrid frequency control while optimizing the active power output of WTG and ES, reducing the wind power curtailment ratio, and achieving the goal of efficient utilization of energy. One more feature of the proposed strategy is the low dependence on the model parameter, which is conducive to robustness.
作者
张靖
张志文
胡斯佳
李勇
林锦杰
Zhang Jing;Zhang Zhiwen;Hu Sijia;Li Yong;Lin Jinjie(College of Electrical and Information Engineering Hunan University, Changsha 410082 China;Hunan Engineering Research Center of Large-Scale Battery Energy Storage Application Technology, Changsha 410000 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2022年第15期3767-3780,共14页
Transactions of China Electrotechnical Society
基金
国家重点研发计划政府间国际科技创新合作重点项目(2018YFE0125300)
国家自然科学基金项目(52061130217)
湖南省科技重大专项项目(2020GK1013)
湖湘高层次人才聚集工程项目(2019RS1016)
长沙市杰出创新青年计划(KQ2009037)
中央高校基本科研业务费(531118010661)资助。
关键词
独立微电网
调频
功率柔性分配
能量高效利用
风机
储能
Isolated microgrid
frequency regulation
flexible power distribution
efficient utilization of energy
wind turbine generator
energy storage
