Decentralized Cooperative Control for Smart DC Home With DC Fault Handling Capability

Abstract

This paper presents a decentralized cooperative control (DCC) method along with a fault segment identification (FSI) scheme to achieve the control and protection objectives for a smart dc home by using only local measurements. The dc home is interfaced with the utility grid via a new modular multilevel converter configuration. Distributed generators are also integrated into the dc home via power converters to guarantee sufficient energy capacity and to support ac and dc loads consumption in the off-grid mode. The proposed DCC method ensures accurate current sharing, dc bus voltage regulation, and fast restoration after the fault clearance. On the other hand, the main objective of the proposed FSI scheme is to quickly identify and isolate the faulty segment to protect the sensitive power electronic components in the dc home from the high fault current. The FSI technique identifies the faulty segment by using only the information extracted from the local current sensor. Time-domain simulation studies using detailed nonlinear models confirm the effectiveness of the proposed control and protection schemes under various normal and faulted operating scenarios. Hardware-in-the-loop studies demonstrate the feasibility of hardware implementation and verify the proposed system performance.