基于混合储能的电网友好型分布式电源的控制策略研究

本文提出了一种由间歇式可再生能源发电系统、能量型和功率型混合储能系统组成的分布式电源的控制策略．该控制策略包括直流母线电压控制和交流换流器的电网自适应控制两部分．首先，本文提出了直流侧可再生能源发电及混合储能系统之间的协调控制策略，并利用直流母线电压分区控制和DC／DC变换器多运行模式归一化模型有效地实现了直流母线电压稳定及各种运行模式的平滑切换，优化了锂电池的充放电过程，提高了储能系统的技术和经济性能；其次，提出了基于电压源下垂控制的交流侧挟流器的电网自适应控制策略，引入了虚拟阻抗和自同步控制，提高了分布式电源的电网适应性，最后，通过PSCAD／EMTDC的建模仿真，验证了本文控制策略的有效性．

Study on Control Strategy of Grid-friendly Distributed Energy Resources Based on Hybrid Storage System

This paper proposed a novel control strategy of distributed energy resources （DR） com- prised of distributed intermittent renewable energy generation, high energy density storage system-lithi- um battery （LB）and high power density storage system-super capacitor （SC）. The proposed control strategy of DR comprises two control loops： coordinated control of dc-link system and adaptive control of AC converter. In this paper, first, coordinated control of de-link system is introduced, a novel dc link voltagezone controiand a unified multi-mode control model are adopted to realize stable dc-link voltage and smoothly transfer between multi operationmodes, meanwhile the charging/discharging of LB is opti- mized. Second, theadaptive control of ac converter based on voltage source converter （VSC） droop con- trol is introduced, virtual impedance and re-synchronous control are adopted to enhance the grid adapta- bility of DR. Finally, the performance of the proposed control strategy is verified by digital time-domain simulation studies in PSCAD/EMTDC software environment.