Power Flow Analysis of Islanded Microgrids: A Differential Evolution Approach

Abstract

Power flow (PF) analysis of microgrids (MGs) has been gaining a lot of attention due to the evolution of islanded MGs. To calculate islanded MGs' PF solution, a globally convergent technique is proposed using Differential Evolution (DE)-a popular optimization algorithm for global non-convex optimization. This paper formulates the PF problem as a constrained optimization problem (COP) considering all the operating conditions of the Droop Controlled Islanded MGs (DCIMGs). To solve the proposed COP, DE-NGM, (Epsilon based Differential Evolution with Newton-Gauss-based mutation) is proposed. The proposed algorithm, DE-NGM, is a novel variant of DE since it comprises a novel mutation operator, Newton-Gauss-based mutation (NGM). NGM includes all the important features of DE's mutation strategies as well as reduces the constraint violation by utilizing the information of constraint-space. Numerical experiments validate that the global convergence ability of proposed algorithms in solving COPs than existing state-of-the-art algorithms. Furthermore, the proposed algorithm as a PF tool has better robustness than existing tools on ill-and well-conditioned systems with heavy loads, different limit violations, and inappropriate final solutions (far from the flat start). The performed comparative analysis confirms good agreement of accuracy and efficacy with the existing method for islanded MG's PF.

Steady‐state operating points of islanded virtual synchronous machine microgrid

“…In an IM, DGs are modeled in three modes, that is, PV, PQ, and droop. 3,23,33,47 However, there is an exemption as it is not all DG buses that can be modeled as droop buses. VISMA has an inherent natural droop characteristic and can work without externally added droop.…”

“…Generally, DGs are modeled as PV or PQ buses in the grid grid‐connected system but is impossible in IM to operate all DGs in PQ or PV mode because of the absence of a slack bus. In an IM, DGs are modeled in three modes, that is, PV, PQ, and droop 3,23,33,47 . However, there is an exemption as it is not all DG buses that can be modeled as droop buses.…”

Distributed Dynamic Event-Triggered Control for Voltage Recovery in Islanded Microgrids by Using Artificial Delays

“…To validate the effectiveness of the proposed strategy (20), (22), and (23) in solving voltage recovery problem in MG, here we consider the IEEE 14-bus test system working in islanded mode. Note that, according to the IEEE Standard 1547.4 [48], it is a common practise to properly modify the IEEE 14-bus test system, or even larger IEEE test systems, so to simulate a MG and validate the robustness of the proposed distributed control scheme, along with its scalability requirement (see, e.g., for more details [49], [50]). N = 5 DGs on buses 1, 2, 3, 6 and 8 are involved into the grid, along with M = 9 local loads and twenty power transmission lines, whose parameters are detailed in [51].…”

A Comparison of Power Flow Based on Bus Admittance Matrix for Networked Microgrid Energy Management Gy Management

“…The power flow in NMGs is influenced by both operating modes (e.g., grid connected or islanded mode) and control modes (e.g., primary, secondary, and tertiary control) [12]. The utility grid controls the frequency of NMGs in grid-connected mode by means of the point of common coupling (PCC), while distributed generators (DGs) use the PQ and PV control schemes [13,14]. For NMGs islanded mode, decentralized droop control schemes are used to meet load demands while maintaining system frequency and bus voltages.…”