Estudo Comparativo entre Estratégias de Controle Clássico PI e uma Proposta de Controle Adaptativo Aplicadas a um Sistema PV-UPQC Monofásico

This paper presents a comparative analysis involving classical proportional-integral (PI) controllers and an adaptive controller proposal. All the controllers are applied to the single-phase distributed generation control loop composed of a single-stage photovoltaic system integrated into a unified power quality conditioner (UPQC). The integration of the photovoltaic (PV) system with the UPQC allows, at the same time, the injection of active energy into the utility grid and active power-line conditioning. Thus, besides the PV system conventional function, the system also improve power quality indicators once an effective power factor correction is carried out and local loads are fed with sinusoidal and regulated voltage. The proposed adaptive controller is based on the adaptive control reference model and acts by comparing the model dynamics with the process dynamics. Thus, the error between these components is minimized according to a proper adjustment mechanism. As a result, optimal controllers gains are obtained, meaning that the system process output will be as close as possible to the model output. Simulation results are presented to evaluate the system dynamic performances operating with adaptive controllers and classical PI controllers when the system under study is subjected to disturbances like abrupt solar irradiation changes and load transients.