适应于海岛独立微网的交直流混合风力发电系统及其优化调度策略

Hybrid AC/DC Wind Energy System in an Independent Island Microgrid and Its Optimal Dispatching Strategy

独立海岛交直流微电网（independent island hybrid microgrid,IIHM）能有效解决海岛供电难题,但可再生能源出力的波动加剧了交直流子微网的功率不平衡情况,导致功率在传输变换过程中产生较大损耗。因此,该文设计了一种交直流无刷双馈风力发电机（hybrid brushless doubly-fedinduction generator,HBDFIG）,通过主动调节发电机转速与控制绕组电流频率,可在发电侧将功率按一定比例直接分配到交流与直流子微网。在此基础上,以保障负荷全部供电为前提,以消耗海岛内发电燃料最少为目标,提出了含HBDFIG的IIHM优化发电调度策略。算例结果表明HBDFIG及其优化发电调度策略可减少功率在微网内的传输变换损耗,提高供电效率,延长常规燃料补给周期,降低海岛微网综合运行成本。

Independent island hybrid microgrid （IIHM） can provide island power supply effectively. But the fluctuation of renewable energy exacerbates power unbalance in the AC/DC sub-microgrid, which leads to more power loss in the process of power transmission and transformation. In this paper, a hybrid brushless doubly-fed induction generator （HBDFIG） was proposed. It can adjust the generator speed and the current frequency of control winding actively, which can directly distribute the power to AC/DC sub-microgrid in proportion. On this basis, we proposed the optimal power dispatching strategy of IIHM with HBDFIG. The strategy is based on the premise of meeting all the load demand and the objective function of consuming the minimum fossil fuel in the island. The simulation results show that HBDFIG and its power dispatching strategy can decrease the power loss of power transmission and transformation, improve the power supply efficiency, extend the replenishment cycle of fossil fuel and decrease the overall operation cost of IIHM.