Adaptive control technique for suppression of resonance in grid‐connected PV inverters. Issue 6 (7th March 2019)

• Record Type: Journal Article
• Authors: Goh, Hongsoo; Armstrong, Matthew; Zahawi, Bashar
• Is Part Of: IET power electronics. Volume 12:Issue 6(2019)
• Page Start: 1479
• Page End: 1486
• Publication Date: 2019-03-07
• Subjects: photovoltaic power systems -- invertors -- adaptive control -- band‐pass filters -- power grids; adaptive control technique -- grid‐connected PV inverters -- grid operating conditions -- harmonic performance -- resonant performance -- grid‐connected photovoltaic inverters -- grid impedance -- PV inverter -- adaptive control algorithm -- resonance condition -- grid inductance variation -- distribution grid -- single‐phase grid‐connected inverter -- resonant excitation suppression -- active band‐pass filter -- voltage 240.0 V -- apparent power 2.0 kVA; Power electronics -- Periodicals; 621.31705
• DOI: 10.1049/iet-pel.2018.5170
• Languages: English
• ISSNs: 1755-4535

Abstract

Abstract : 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.