Application control configurations in a photovoltaic inverter operating in a microgrid

This work presents the development and implementation of four control configurations for photovoltaic inverter. These configurations are: Proportional Integral plus Resonant controller, Proportional Integral plus Repetitive controller, Proportional Integral-Proportional plus Resonant Controller and Two Degrees of Freedom plus Repetitive control with the aim of reducing the Total Harmonic Distortion in Voltage. These techniques are useful in island mode operation of an inverter when it is working as a voltage source in microgrid. In this operation mode, these control techniques are successfully applied when the inverter feeds linear and nonlinear loads. The purpose is to keep the output voltage waveform, frequency and amplitude according to the standard IEEE 519. It is use is justified because currently most of the loads have nonlinear characteristics which increase considerably the Total Harmonic Distortion in voltage. A comparative analysis derived from inverter simulations with nonlinear loads has been performed in order to validate those control techniques, considering that its application to feed line loads proves to be effective.