An Improved Sliding Mode Control for Grid Connected Inverters

Abstract

This research work presents an exponential reaching law with Rotating Sliding Surface (ERL-RSS) based Sliding Mode Control (SMC) for Three-phase inverters connected to a grid. This study addresses the need for effective control techniques in the context of LCL Filter-based Three-Phase Grid-Connected Inverters (LCL-GCIs), which are a vital component of current power systems. SMC is well-known for its fast dynamic response, ability to reduce periodic interferences, and adaptability to non-linear restrictions. However, the existence of undesired chattering effects frequently compromises its robustness. Traditional SMC’s resilience is sometimes challenged by the unwanted chattering phenomena, despite its reputation for quick transient response, competent periodic interference attenuation, and capacity to accept nonlinear constraints. This idea of a unique technique for improving the performance of Three-Phase grid-connected inverters called the Exponential Reaching Law with Rotating Sliding Surface included in the SMC framework to address this trade-off between robustness and chattering significantly increases the performance of the control system. To develop an effective control surface, the proposed technique exploits a time-varying surface that relies on error signals from the grid. The study presents an in-depth analysis as well as a detailed design technique, illustrating the suggested approach’s step-by-step implementation. The suggested ERL-RSS-based SMC is compared to several current control systems in a comparative study. The findings of this analysis demonstrate the effectiveness of the proposed control technique. The work covers the design of a simulation model for a 50kW Grid-Connected Inverter in MATLAB/Simulink. The simulation results show that the suggested SMC technique distributes electricity to the grid effectively, with much lower harmonic distortions and a shorter settling time. This study highlights the ERL-RSS-based SMC’s potential as a robust and high-performance control solution for improving the functioning of Three-Phase grid-connected inverters in current power systems.