An OCC-APF control strategy for unbalanced grid conditions

In this work it is proposed a DSP based, OCC control strategy for APF, which is able to work in case of unbalanced grid voltage, i.e. when it is affected by a common mode voltage. Proposed strategy is based on an OCC rectifier control which utilizes an input resistance control to set up dc-link voltage and achieve a unity power factor as well, and a lead-lag compensator to average phase current. In this sense, APF proposed strategy uses input resistance control while lead-lag compensator is used to filter harmonics in grid current. Simulation and experimental results confirm present proposal.