A generalized approach for harmonics and unbalanced current compensation through inverter interfaced distributed generator

Harmonics and unbalanced current compensation in the distribution grid has become a major concern due to connections of nonlinear and unbalanced loads and high penetration of renewable energy sources. To tackle this problem, the increasing integration of inverter interfaced distributed generation (DG) may actually be considered able to provide ancillary service for power quality support, if controlled and regulated properly. The challenging part consists of precisely extracting the current to be compensated in a fast dynamics and accurately tracking the compensation reference as close and as fast as possible. Most of the existing control methods are developed for selected harmonics compensation, thus not appropriate for the scenarios with wide range of harmonics due to the increasing implementation complexity. Therefore, this work proposes an approach to compensate harmonics and unbalance in a generalized way aiming to correctly compensate wide range of harmonics with less complexity and computation effort. Simulation and hardware-in-the-loop (HIL) experiment results are provided to validate the proposed approach.