Stability Analysis of Primary Plug-and-Play and Secondary Leader-Based Controllers for DC Microgrid Clusters
Stability Analysis of Primary Plug-and-Play and Secondary Leader-Based Controllers for DC Microgrid Clusters
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DOI：
10.1109/tpwrs.2018.2884876
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发表时间：
2019-05-01
影响因子：
6.6
通讯作者：
Ferrari-Trecate, Giancarlo
中科院分区：
文献类型：
--
作者：
Han, Renke;Tucci, Michele;Ferrari-Trecate, Giancarlo
本文提出了一种新的微电网(MG)集群递阶控制方案，该方案将原子直流MG与ZIP负载互联，每个MG由并网和馈网变流器组成。在初级，我们开发了一种新的即插即用(PnP)电压/电流控制器，以实现本地基准电压支持和电流馈电功能。每个镇定控制器的系数都用显式不等式表示，它只与MG的局部电气参数有关。此外，我们还给出了保证电力系统无源性和渐近稳定的ZIP负载的一个充分条件。并证明了性能对系统不确定性的稳健性。在第二级，提出了一种基于领导者的电压/电流控制器，以实现对MG集群的电压和电流的调节，而不需要为每个MG指定单独的设置点。所提出的分布式控制器需要一个通信网络，其中每个调节器只与其通信邻居交换信息。利用所提出的方案，每个MG可以无缝地插入/拔出，而与其他MG的电力线参数和型号无关。形式化地证明了MG簇的闭环稳定性独立于簇的拓扑结构。此外，通过广泛的硬件在环测试验证了理论结果，表明了闭环系统对负载扰动、即插即用操作和通信网络中的噪声/延迟的鲁棒性。
In this paper, we propose a new hierarchical control scheme for microgrid (MG) clusters, given by the interconnection of atomic dc MGs with ZIP loads, each composed by both grid-forming and grid-feeding converters. In the primary level, we develop a new Plug-and-Play (PnP) voltage/current controller in order to achieve simultaneous voltage support and current feeding function with local references. The coefficients of each stabilizing controller are characterized by explicit inequalities, which are related only to local electrical parameters of the MG. Moreover, we provide a sufficient condition on the ZIP loads to guarantee passivity and asymptotic stability of electric system. The robustness of performance to system uncertainties is also demonstrated. In the secondary level, a leader-based voltage/current controller is proposed to achieve both voltage and current regulation for the MG cluster without specifying the individual setpoints for each MG. The proposed distributed controller requires a communication network where each regulator exchanges information with its communication neighbors only. With the proposed scheme, each MG can plug-in/out seamlessly, irrespective of the power line parameters and models of other MGs. Closed-loop stability proof of MG clusters is formally proved independently of the cluster topology. Moreover, theoretical results are validated by extensive hardware-in-loop tests showing robustness of the closed-loop cluster against perturbations in the loads, PnP operations, and noises/delays in the communication network.