Design, Modeling, and Stability Evaluation of a Grid-Interactive Solar PV-Based Electric Vehicle Charging Station with Conditional Utility Support and Hierarchical Energy Management

Abstract

The rapid proliferation of electric vehicles (EVs) is imposing significant operational challenges on modern distribution networks, particularly in regions with increasing electrification of transportation. Solar photovoltaic (PV)-assisted charging infrastructure offers a sustainable alternative; however, conventional grid-connected architectures often maintain continuous utility interaction, thereby limiting renewable penetration and increasing operational cost. This paper presents a comprehensive design, modeling, and stability analysis of a grid-interactive solar PV-based EV charging station incorporating conditional grid participation and hierarchical energy management. The proposed system integrates a 4 kW PV array, an interleaved DC–DC converter with incremental conductance maximum power point tracking (MPPT), a bidirectional battery interface, and a dq-frame controlled grid inverter connected through a regulated DC bus. Unlike traditional architectures, the grid is activated only when renewable generation and battery support are insufficient to meet EV demand. A complete state-space model of the multi-converter system is developed. Small-signal stability, controller tuning methodology, stochastic EV demand modeling, and techno-economic evaluation are performed. Results demonstrate enhanced renewable utilization, reduced grid dependency (approximately 35% reduction), improved voltage regulation, and compliance with harmonic standards. The proposed architecture provides a scalable and smart-grid-compatible framework for distributed EV charging infrastructure.