中文摘要：

针对多微网系统频率控制问题,对微网能量平衡控制、二次频率调整及联络线功率控制等进行了研究,提出了多微网系统二次频率控制策略。按所提控制策略,通过微网中心控制器进行二次频率调整,根据系统频率偏差和联络线功率偏差确定各微网需要调节的功率总量,并按一定的原则分配至调频DG,各DG调整出力将微网频率调整至目标值,并将联络线功率恢复至计划值;以两微网系统为例,对单网内发生负荷波动及双网同时发生负荷波动的情况进行了仿真。研究结果表明,所提控制策略可在系统发生负荷波动时快速恢复联络线功率,同时保证微网系统频率的稳定。

英文摘要：

Aiming at the problem of frequency regulation for multi-microgrid system,power balance,secondary frequency regulation and tieline power control were studied. A novel secondary frequency control strategy was proposed. A microgrid central controller（ MGCC） was designed to undertake the task of frequency regulation. According to deviations of system frequency and tie-line power,the expected total power was calculated,which was allocated to the DGs taking part in the secondary frequency regulation. The DGs adjust their outputs to balance the system power vacancy. Simulation studies were performed on a double-microgrid system. Load fluctuations in one microgrid and in both microgrids were carried out respectively on the test system. The results indicate that the proposed control strategy can help to recover the tie-line power to the planned value and maintain the frequency stable.