This paper presents a methodology to estimate, in the design stage, the total harmonic distortion of the current injected into the power grid by two-stage voltage source inverters (VSI). As such inverters operate in a closed loop, the quality of the grid current is highly dependent on the dynamics of the control loops. Thus, it is necessary to focus on an approach to model the behavior of the grid current considering the closed-loop disturbances. The proposed approach allows deriving an equation to predict the behavior of the current injected into the grid and estimate its harmonic distortion, becoming an important tool for optimal design of grid-connected inverters. To validate the accuracy of the developed methodology, experimental results are presented in different operating scenarios.

Leia Mais: https://onlinelibrary.wiley.com/doi/10.1002/cta.4314