Performance Evaluation of Three‐Phase Grid‐Connected Inverter With Improved SMC‐Based MPC Control Method

ABSTRACT Grid‐connected inverters are widely used in power systems that utilize renewable energy sources. The filter and control method to be used for these grid‐connected inverters plays an important role. Various filter topologies are employed to reduce the harmonics of the grid current. The LCL filter is superior to existing filters in terms of harmonic suppression performance and overcoming unwanted resonant effects. In addition, model predictive control (MPC) techniques are widely used in the literature to regulate the grid dynamics in grid‐connected inverters. Conventional MPC has the advantages of fast dynamics and easy applicability. This paper proposes new MPC methods for a 3‐phase LCL ‐filtered grid‐connected inverter system. The traditional MPC approach may suffer from instability in the case of a poor choice of control parameters. In the proposed method, the traditional MPC method is reformulated to shape the closed‐loop energy. Lyapunov approximation is used to ensure the stability of the proposed control methods, and the control input is determined by assessing the instantaneous stability of the system. The effectiveness of the proposed control methods and the conventional MPC method is tested in the Matlab/Simulink environment by changing the grid reference current step, and it is supported by the implementation of the processor‐in‐the‐loop (PIL). The DSP evaluation board F28379D is used to perform the experimental validation. As a result of the simulation study and PIL implementation, the proposed MPC methods provide better steady‐state performance than the conventional MPC methods.