摘要
直流微电网是通过直流总线聚合分布式发电资源的小型配电网系统.本文针对含有构网转换器和馈网转换器的单总线直流微电网系统,提出一类混合分布式二次均流调压控制策略,实现快速且精确的直流总线电压调控和分布式发电资源电流分配.在控制设计中,对具有电压源特性的构网转换器采用V-I下垂控制策略,对具有电流源特性的馈网转换器采用无下垂形式的二次控制策略.然而,混合模式的反馈设计使得系统的动态矩阵不再具备对称性.对此,本文在稳定性分析中构建由电流误差和电压误差线性融合的误差闭环系统,将微电网的稳定性问题转换成秩一矩阵摄动的特征值分析问题,进一步结合图论和广义负定矩阵性质,推导出使系统稳定的参数取值条件.最后通过数值模拟和硬件实验验证了该方法的有效性.
DC microgrid is a small-scale distribution network system that aggregates distributed generation sources via a DC bus.We present a hybrid secondary controller for a single-bus DC microgrid with grid-forming and grid-feeding converters,to accurately achieve voltage regulation of the DC bus and current sharing among distributed generation sources.In the controller design,a V-I droop based secondary control strategy is adopted for grid-forming converters that operate as voltage sources,while a droop-free based secondary control strategy is adopted for grid-feeding converters that operate as current sources.However,mixing these two different secondary controllers results in an asymmetric dynamical matrix for the system.To address this,a linear combination of current and voltage errors is introduced,along with an associated closed-loop system.The microgrid control problem is transformed into a stability problem of rank-one perturbations in matrices.Furthermore,by graph theory and properties of generating negative definite matrices,the stability criterion is derived.Finally,the effectiveness of the method is verified through numerical simulations and hardware experiments.
作者
刘骁康
王致恒
邢兰涛
王燕舞
张承慧
Xiaokang LIU;Zhiheng WANG;Lantao XING;Yanwu WANG;Chenghui ZHANG(School of Arti cial Intelligence and Automation,Huazhong University of Science and Technology,Wuhan 430074,China;School of Control Science and Engineering,Shandong University,Jinan 250061,China)
出处
《中国科学:信息科学》
北大核心
2025年第10期2622-2636,共15页
Scientia Sinica(Informationis)
基金
国家自然科学基金(批准号:62233006,62473164)资助项目。
关键词
直流微电网
分布式二次控制
均流调压
稳定性分析
微电网控制
DC microgrids
distributed secondary control
voltage regulation and current sharing
stability analysis
microgrid control
