Optimizing Power Quality and System Stability in Grid-Connected Renewable Energy and BESS for Industrial and Commercial Loads

The integration of grid-connected renewable energy sources and Battery Energy Storage Systems (BESS) in industrial and commercial applications presents challenges in maintaining power quality and system stability. The presence of linear, non-linear, and unbalanced loads, along with three-phase induction motors, leads to voltage fluctuations, harmonic distortion, and power imbalances. Additionally, the intermittent nature of solar energy further complicates system stability. This paper proposes an adaptive control strategy for multifunctional grid-tied inverters to mitigate power quality disturbances and optimize energy management between renewable sources, BESS, and the grid. Based on Conservative Power Theory (CPT), the strategy enables real-time extraction and compensation of oscillating power terms in the abc frame. A three-phase grid-tied inverter with an LCL filter is used in a laboratory-scale prototype to evaluate the system’s effectiveness under various load conditions. Simulation results confirm that the proposed strategy reduces total harmonic distortion (THD), improves voltage regulation, and enhances frequency stability. Additionally, it ensures stable induction motor operation with constant torque and improves overall power quality in industrial and commercial settings. These findings validate the practical applicability of the proposed method for enhancing the performance and reliability of grid-connected renewable energy systems.