自适应下垂控制的多光伏源直流微网功率分配

Adaptive Droop Control of Multi-PV Source DC Microgrid Power Distribution

现有直流微网下垂控制普遍采用固定下垂值,因此存在电压恢复能力差且无法应对瞬时电压的问题,为此提出一种自适应比例下垂指数控制的多光伏源直流微网功率分配策略。基于归一化电流分配差值和变流器输出侧电压偏差值的函数,引入比例下垂指数(PDI)算法实现对微网负荷的功率比例分配。在此基础上引入下垂电阻自适应更新策略,借助两个下垂校正因子实时更新下垂电阻值,以解决电压恢复能力差和瞬时电压跌落的问题,同时消除传统下垂控制在电流分配和电压调节之间的矛盾。最后搭建实验样机对所提方案进行验证,实验结果表明所提方案实现了微网负荷的比例分配和负荷电压的快速恢复,从而提高系统的整体性能。

Current DC microgrid droop control generally adopts fixed droop value,so the voltage recovery ability is poor and can not deal with instantaneous voltage problems,so a multi-PV source DC microgrid power distribution strategy with adaptive proportional droop index control is proposed.Based on the function of the normalized current distribution difference and the voltage deviation of the converter output side,the proportional droop index(PDI)algorithm is introduced to realize the proportional power distribution of the microgrid load.On this basis,the droop resistance adaptive updating strategy is introduced,and the droop resistance value is updated in real time with the help of two droop correction factors to solve the problem of poor voltage recovery ability and instantaneous voltage drop,and to eliminate the contradiction between current distribution and voltage regulation in traditional droop control.Finally,an experimental prototype is built to verify the proposed scheme.The experimental results show that the proposed scheme realizes the proportional load distribution and the rapid load voltage recovery of the microgrid,thus improving the overall performance of the system.