Análise de controladores de corrente de um sistema de geração fotovoltaico com mitigação de correntes harmônicas na rede elétrica

Abstract

In this work the behaviour of a grid connected photovoltaic (PV) power generation system was evaluated. The PV system has a nominal generation capacity of 6.7KWp and the applications of Proportional Integrative (PI) and Proportional Multiresonant (P-Multiresonant) current controllers in the current control loops are analyzed.A non-linear load is connected to the common coupling point (CAP) and demands a non-sinusoidal current that must be fully supplied. An active power filter (APF) is added to the CLR through an algorithm that allows to compensate the harmonic components present in the grid currents. The system structure consists of a PV arrangement with modules in series. The model of the PV modules is single diode with parameters obtained from the manufacturer BYD with model B6K-36, which in turn is connected to the boost type elevating converter. The boost converter is connected to the CLR by means of a DC bus, with fixed voltage. In this scheme, the CLR controllers, in αβ coordinates, are responsible for controlling the DC bus voltage, the current supplied to the PAC, the active and reactive powers. The results were obtained using Matlab/Simulink computer simulation software. Two case studies are analysed to investigate the effectiveness of the current controllers employed in the CLR. In case 1, the PV system operates with the PI current controller of the CLR, in the conditions without PAF actuation and with PAF actuation, and in case 2, the PV system operates with the P-Multi-resonant current controller, in conditions with PAF actuation or without PAF actuation to the CLR. The T HDi (Total Harmonic Distortion) of 19.4% was reduced to 4.06% (case 1) and the T HDi of 10.14% was reduced to 1.04% (case 2) when the PV system operates in its nominal conditions. Thus, the controller used in case 2 proved to be more effective for PV generation and power quality improvement.