Metodologia para auto-ajuste de controladores de corrente em conversores Fonte de Tensão conectados a redes sujeitas a distúrbios harmônicos

Abstract

This work proposes a new methodology that allows a voltage source converter to connect to a grid with unknown parameters and operate with a self-adjusting closed-loop control, thus avoiding the presence of an operator for the tuning of control parameters, facilitating its self-commissioning. In order to do this, the method utilizes an impedance detection technique based on the injection of an uncharacteristic harmonic signal with a hysteresis band controller, and then automatically adjusts the controllers responsible for asymptotic reference tracking and resonance rejection. In addition, a disturbance rejection analysis is proposed with the objective of tuning resonant controllers based in power quality requirements. Mathematical models are also proposed considering the influence of the grid’s impedance characteristic on the reference tracking and disturbance rejection analyses. The proposals are validated through simulations and experiments