Enhancing Smart Grid Performance: A Multi-Objective V2G and Capacitor Allocation with Rigorous Load Modeling

Abstract

This paper presents a comprehensive strategy to enhance the performance of smart distribution grids through a multi-objective optimization approach targeting both power loss minimization and voltage stability improvement. A novel voltage stability index (VSI) is derived from the bi-quadratic load flow formulation, integrated with a modified load flow algorithm based on the Bus-Injection to Branch-Current (BIBC) and Branch-Current to Bus-Voltage (BCBV) matrices, enabling efficient computation for large-scale radial distribution networks (RDNs). Unlike conventional approaches, this work incorporates detailed load modeling, including constant power, constant current, constant impedance (CP, CI, CZ), composite (ZIP), and exponential models, to capture realistic system behavior under varying load conditions. Simulation studies on IEEE 29- and 85-bus test feeders validate the proposed strategy. Results show that, for the 29-bus RDN, optimal allocation of Vehicle-to-Grid (V2G) units and Shunt Capacitors (SCs) reduces real power losses by 45% (from 46.8 kW to 25.7 kW) and improves the minimum bus voltage from 0.8348 p.u. to 0.9631 p.u.. For the 85-bus RDN, losses are reduced by 44% (from 316.1 kW to 176.1 kW), with the minimum bus voltage improving from 0.8454 p.u. to 0.9245 p.u.. Moreover, the minimum VSI increased from 0.7289 to 0.8868 in the 29-bus system and from 0.5764 to 0.8149 in the 85-bus system, confirming substantial gains in system resilience. Comparative analysis demonstrates that rigorous load modeling significantly influences the identification of critical nodes and the optimal placement of compensating devices. The proposed approach consistently improves voltage profiles, enhances stability margins, and reduces network losses more effectively than conventional methods.

Article Content

Keywords

Article Info