The study system in this paper is an islanded DC-microgrid comprising DFIG wind turbines (WTs), microturbine and loads. The main focus of this paper is on local control strategies design for the DFIG-WTs and microturbine to obtain short time-scale coordination, seamless power management and proper load sharing between WTs in the study system. In this work, control strategies related to the DFIG-WTs are extracted and then modified by adding an auxiliary control block, known as wind power curtailment block (WPCB), that adjusts the WT reference power according to the local DC bus voltages. Hence, as long as there is sufficient load demand, the WTs inject available power to the microgrid. Once available wind power exceeds the load demand, WTs adaptively curtail the injected power and seamlessly track the varying load. Next, the control structure of the so-called WPCB is further modified to realize proper load sharing between different WTs. Hence, by using the improved control structure of each WT, not only the proper and seamless power management is realized, but also, the load power is appropriately shared between different WTs according to available wind power. At the end, theoretical results are verified by time-domain simulations in the Matlab-Simulink environment.

本文的研究系统是一个孤岛式直流微电网，包括DFIG风力涡轮机（WTs），微型涡轮机和负载。本文的主要重点是针对DFIG-WT和微型涡轮机的局部控制策略设计，以在研究系统中获得短时间尺度的协调，无缝的电源管理以及WT之间适当的负载分配。在这项工作中，与DFIG-WTs相关的控制策略被提取，然后通过添加一个辅助控制模块（称为风电削减模块（WPCB））进行修改，该控制模块根据本地DC总线电压调整WT参考功率。因此，只要有足够的负载需求，WT就会向微电网注入可用功率。一旦可用风力超过负载需求，WT将自适应地减少注入的功率并无缝跟踪变化的负载。下一个，进一步修改了所谓的WPCB的控制结构，以实现不同WT之间适当的负载共享。因此，通过使用每个WT的改进的控制结构，不仅实现了正确和无缝的功率管理，而且根据可用的风力在不同的WT之间适当地分配了负载功率。最后，在Matlab-Simulink环境中通过时域仿真验证了理论结果。