An active-damped LLCL filter for grid-tied three-phase voltage source inverter with PR current control

Abstract

For the grid connection of voltage source inverters (VSIs), the power passive filters are a standard solution for grid-current harmonic attenuation. However, these types of filters may cause resonance between the inverter and the grid. Passive and active damping techniques are employed for resonance attenuation. Efficiency concerns have set active damping techniques as a promising solution for the resonance problem compared to the passive damping techniques. Characteristics, performance, effect of different active damping schemes, and stability analysis were investigated for the LLCL passive filter in literature. In this paper, the characteristics and performance, of active damping technique applied to an LLCL passive power filter interfacing a three-phase VSI to the grid are investigated. Stability analysis is conducted for the LLCL-based grid-connected VSI. The presented concept has been elucidated by simulation results using Matlab/Simulink platform and validated through experimental results. 2016, Institution of Engineering and Technology. All rights reserved.