Stability of the Small-Scale Interconnected DC Grids via Output-Feedback Control


A decentralized nonlinear model and controller is proposed to stabilize the interconnected small-scale islanded dc grids in the presence of renewable energy sources with proven stability in this paper. The dc interconnected network comprises dc sources along with resistive and constant-power loads (CPLs). Though the dc sources are photovoltaic (PV) in this paper, the proposed controller can be applied to other types of low-inertia intermittent sources as well. All sources and/or CPL loads are connected to the grid through simple dc-dc converters (DDCs) to avoid power electronic complexities. The negative-resistance CPLs can destabilize the grid in the presence of the DDC dynamical components. The decentralized nonlinear output-feedback controller mitigates rapid voltage and power oscillations caused by the disturbances and measurement noises, and stabilizes the grid. Since the proposed output-feedback controller needs only partial knowledge of the local converter states, the number of measure points reduces leading to a simple implementation. Simulation results on a small-scale dc grid are provided to show the performance of the proposed controller.


Electrical and Computer Engineering


This work was supported by NSF CAREER ECCS under Grant 1151141.

Keywords and Phrases

Controllers; DC-DC converters; Decentralized control; Electric inverters; Electric power system control; Electric power system interconnection; Electric power transmission networks; Feedback control; Power converters; Renewable energy resources; Constant power load (CPLs); DC distribution system; Micro grid; Neural networks (NN); Nonlinear output feedback controller; Output feedback; Output feedback controller; Output feedback controls; Feedback; Microgrids

International Standard Serial Number (ISSN)

2168-6777; 2168-6785

Document Type

Article - Journal

Document Version


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