Implementation of ANFIS-Based PID Controller in a Three-Phase Solar PV-Integrated UPQC for Power Quality Improvement

The incorporation of renewable energy sources into the grid presents challenges like reactive power compensation, harmonics, voltage sags, and swells, which impact power quality. This paper proposes a single-stage PV-linked Unified Power Quality Conditioner (PV-UPQC) for a three-phase grid-connected system to address these issues while optimizing PV energy utilization. The system employs Perturb and Observe (P&O) MPPT for maximum power extraction and an Adaptive Neuro-Fuzzy Inference System (ANFIS)-based PID controller for dynamic inverter switching, ensuring precise tuning and adaptability. Simulation analyses under various load scenarios and grid disturbances demonstrate the system’s capability to enhance power quality. The ANFIS-PID controller achieves superior performance with balanced gain values (Kp = 1, Ki = 1, Kd = 0.01), reducing steady-state error and improving response time. It maintains a refined DC link voltage range of 660–700 V, outperforming other methods. The outcomes verify that the proposed PV-UPQC system effectively integrates renewable energy, stabilizes voltage, and mitigates power quality issues, making it an ideal solution for modern grid-connected applications.