A Three-Phase Uninterruptible Power Supply using Multivariable Repetitive Robust Model Reference Adaptive Control

Abstract: This paper presents a multivariable repetitive robust model reference adaptive controller (MIMO RMRAC-RP) applied to a three-phase uninterruptible power supply (UPS). Using ab0 transformation and balanced three-phase load, the plant can be considered weakly coupled, and then a multivariable law may have its parameters reduced in number, reducing the computational effort to adapt them. For this MIMO RMRAC-RP with reduced number of parameters, the augmented error equation is written, and the adaptation algorithm convergence mathematical proves are developed, as well as the proof of the overall closed-loop system stability, despite the presence of unmodeled dynamics and bounded disturbances. Experimental results confirm good performance for linear and non-linear balanced three-phase loads. Key-Words: Multivariable control Model reference adaptive control Robust adaptive control Repetitive control Uninterruptible power suppl