Open AccessAdaptive control technique for suppression of resonance in grid‐connected PV inverters
Author(s) -
Goh Hongsoo,
Armstrong Matthew,
Zahawi Bashar
Publication year - 2019
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2018.5170
Subject(s) - photovoltaic system , control theory (sociology) , inductance , controller (irrigation) , grid , inverter , grid connected photovoltaic power system , capacitor , electrical impedance , equivalent impedance transforms , harmonic , computer science , electronic engineering , maximum power point tracking , engineering , physics , electrical engineering , voltage , acoustics , mathematics , control (management) , agronomy , geometry , artificial intelligence , biology
Grid operating conditions have a significant effect on the harmonic and resonant performance of grid‐connected photovoltaic (PV) inverters and changes in grid impedance can cause a notable change in the resonant excitation between the PV inverter and the grid. This study proposes an adaptive control algorithm for grid‐connected PV inverters to suppress the resonance condition excited by grid inductance variation, resulting from the dynamic changes in the operating conditions of the distribution network. The causes of resonance between grid‐connected PV inverters and the distribution grid are discussed and the design of an active band‐pass filter for capturing resonance is described. The proportional gain within the proportional–integral controller is then adaptively controlled in real time to compensate for changes in the grid impedance and suppress resonant excitation while maintaining excellent low‐order harmonic performance compared with alternative fixed gain controller techniques, particularly for systems with high values of grid inductance. The performance of the proposed controller is experimentally verified using a 240 V, 2 kVA single‐phase grid‐connected inverter.