A Lyapunov-Stable Integrated MPC & PLC Strategy for Real-Time Energy Management of Hybrid-Performance Rooftop PV Systems

The rapid expansion of renewables within modern power systems has increased the demand for advanced strategies capable of ensuring both economic and operational reliability. This study introduces a stability-guaranteed, predictive control framework for real-time energy management of hybrid rooftop PV systems. The proposed approach integrates a Siemens S7-314C-2DP programmable logic controller (PLC) with a model predictive controller (MPC) to minimize the levelized cost of electricity (LCOE), reliability, and loss of load probability (LOLP) while accounting for switching penalties, voltage and frequency constraints. Furthermore, a Lyapunov-based stability analysis is employed to formally guarantee asymptotic stability of the hybrid system under all switching scenarios. The PV and battery subsystems are mathematically modeled using nonlinear diode and Thevenin equivalent circuits, and power balance at the point of common coupling (PCC) is explicitly formulated. Field experiments on a 10.2 kW hybrid rooftop PV system, combined with predictive simulations, demonstrate that the proposed strategy reduces LOLP, improves reliability to above 99.04%, and increases net monthly revenue by 1.21 times compared with baseline operation. These findings confirm the feasibility and robustness of integrating theoretical stability guarantees with practical PLC implementation for sustainable rooftop PV energy management. Notably, the optimized configuration led to an increase between 63$ to 72$ of the net monthly income too.