A droop control incorporated dc equivalent power flow method for distribution and low voltage systems

Rapid growth in the use of distributed generations in low voltage (LV) and medium voltage (MV) network is attributed the distribution systems 'active', which has made distribution power flow analysis a hot area of research. In this paper, a droop control based distribution power flow formulation is proposed and realized in the dc domain, which is independent of the various assumptions made in existing distribution power flow methods, e.g., unconstrained slack bus capacity, fixed power loads and generations, low R/X ratio etc. And, these assumptions are ill-suited to low and medium voltage systems in both autonomous and grid-connected topology, usually powered by small generators, intermittent renewable sources and also considering the high-resistance interconnecting power lines. The proposed method ensures performance enhancement with better load sharing among sources within the allowable limit. An optimization based numerical solution approach is used for solving the proposed technique. The performance of the system is investigated using a 10-bus low voltage microgrid system and on three IEEE distribution networks, viz., 12-bus, 33-bus, and 69-bus systems. The effectiveness of the proposed method is investigated and compared with existing literature works in terms of reduced power losses, improved voltage profile, R/X sensitivity, and maximum loading point. (C) 2015 Elsevier B.V. All rights reserved.