Optimized Control and Modeling of a Multi-Level Inverter with PSO MPPT for Enhanced Grid Integration of PV Systems

Renewable energy systems face persistent challenges in grid integration due to environmental variability and power quality issues, particularly under partial shading conditions (PSC), where conventional Maximum Power Point Tracking (MPPT) techniques often fail to track the global optimum. While advances in inverter topologies and MPPT strategies have improved performance, many recent implementations still exhibit high total harmonic distortion (THD) levels (1.72–4.58%) and instability during dynamic conditions. This paper presents a robust integration of a 7-level Neutral Point Clamped (NPC) inverter with a Particle Swarm Optimization (PSO)-based MPPT algorithm enhanced by dynamic inertia adjustment (0.4–0.9), aimed at improving power quality and tracking efficiency. Simulations under dynamic irradiance levels (1000–400 W/m²) demonstrate a significant reducstion in current THD to 1.54%, outperforming existing methods. The proposed PSO approach achieves 7.5% higher power extraction than the Perturb and Observe (P&O) method (100kW vs. 93kW), with 8.3% improved voltage stability and a 50% reduction in voltage ripple (±5V vs. ±10V). These results highlight the system’s suitability for utility-scale photovoltaic (PV) integration, offering enhanced efficiency, improved grid stability.