Investigation and implementation of a nonlinear decoupled power control for a single-phase grid-connected power inverter via an LCL filter

Abstract

This paper proposes the study and the implementation of a nonlinear decoupled control approach for the active (P) and the reactive (Q) power in a Single-Phase Grid-Connected Power Inverters (SPG-PIs) application, by using the Proportional Multi-Resonant (PM-R) and the IP Anti-Windup (IP/A-W) controllers. The proposed control technique is characterized by a simple structure that requires less calculation. It is designed to ensure the decoupled P/Q power control guarantees high levels of stability and security of the system operation. In the proposed control scheme, internal feedback, employing the P-MR controllers, is designed for controlling the voltage and the current, and external feedback controls and regulates the powers grid by employing the nonlinear IP/A-W regulators capable to ensure the stability of the system operation with the security functioning. The proposed control method is tested in Matlab/Simulink interface and is validated experimentally on a test bench by using the dSPACE 1202. Obtained results validated the proposed controller performance and prove an acceptable efficiency of the P-MR and the IP/A-W controllers with a Total Harmonic Distortion (THD) conformed to the Algerian local Grid-Code (AGC).