Optimal Coordination of Distributed Generation Units and Shunt Capacitors in Egyptian Distribution System Using Sine-Cosine Optimization Algorithm

In its broadest sense, the particular topology of radial distribution networks (RDNs), high resistance-to-reactance (R/X) ratios, the misuse and exploitation of these systems, specifically with increased variable renewable energy sources (VRESs) that are added in these networks, increased load demands, and nontechnical losses are leading to a significant decrease in voltage magnitude of some buses in these networks with a rapid increase in energy losses and voltage drop values. Therefore, improving the power quality (PQ) and reliability performance levels of RDNs has become an authoritative goal for system operators. Accordingly, in this work, smart coordination of distributed generation units (DGUs) and shunt capacitors (SCs) in Egyptian RDN is presented to increase resiliency and enhance the reliability of this system. The sine-cosine optimization (SCO) algorithm was used to solve the formulated multi-objective (MO) constrained optimization problem. The various objectives presented in this work aim to reduce the operating costs of the system and investment expenses for the proposed coordinated DGUs and SCs in the system while maximizing the benefits (savings) of reducing energy loss and contracted power from the utility, in addition to improving the voltage profile and loading capacity of the system. Three different loading levels were investigated in this work. Various linear and nonlinear constraints were taken into account. A weighted sum approach using the well-known analytic hierarchy process (AHP) was used to transform the MO problem into a normalized single-objective (NSO) optimization problem. The results obtained show a significant techno-economic enhancement of the PQ performance level of the system. Besides, SCO’s results outperformed the results attained using other considered algorithms presented in the literature to solve the problem.