Estudo comparativo de controladores de tensão aplicados a inversores monofásicos

Abstract

This work presents a comparative study between control strategies for the output voltage of inverters. The proposed controllers are applied to the output stage of an Uninterruptible Power Supply (UPS) single-phase. Three control methodologies are discussed: in the first, the internal model principle is applied for the design of a resonant controller in the form of a transfer function; in the second, the model of the resonant controller is written in the form of a state space and a feedback control of states is performed with gains generated by an optimal controller of the Linear Quadratic Regulator (LQR) type; the third one employs a single-phase transformation of coordinates αβ − dq and it is possible to use a simpler proportional integral (PI) controller. Real-time simulation results (HIL - Hardware-In-the-Loop) are performed to validate the performance of controllers against load variations and tracking of the reference signal.