'Institute of Electrical and Electronics Engineers (IEEE)'
Doi
Abstract
Theproportional+resonant (PR) controller has been
proposed in the past as a suitable method to control the current
generated by the grid-connected photovoltaic voltage source inverters.
Due to the fact that information regarding the frequency
of the grid is needed to use this control technique, the synchronous
reference frame phase-locked loop (SRF-PLL) is commonly used.
To assure that the total harmonic distortion of the injected current
(THDi) meets the appropriate standards, even if the grid voltage
is polluted and its frequency varies, an adaptive control strategy
is presented in this paper. This control strategy can improve the
behavior of both, the conventional SRF-PLL and the conventional
PR controller, when they are used in a polluted grid with a time
varying frequency. The experimental results obtained by means of
a digitally controlled 10-kVA inverter, show up that the THDi of the
injected current is improved when the proposed adaptive control
strategy replaces the conventional one.This work was supported by the Spanish Ministry of Science and Innovation under Grant ENE2009-13998-C02-02. Recommended for publication by Associate Editor B. Lehman.González Espín, FJ.; Gabriel Garcerá; Patrao Herrero, I.; Figueres Amorós, E. (2012). An Adaptive Control System for Three-Phase Photovoltaic Inverters Working in a Polluted andVariable Frequency Electric Grid. IEEE Transactions on Power Electronics. 27(10):4248-4261. https://doi.org/10.1109/TPEL.2012.2191623S42484261271