A New Strategy for Decoupling Direct and Quadrature Currents in a Rotating Frame Current Regulator. Application to a Single-Phase Three-Level Boost Rectifier

A new Direct and Quadrature current decoupling strategy is presented which uses a filtering block placed between the current regulation and the modulation stages. This decoupling system is very easy to implement and it represents a clear improvement over the conventional feedforward method in relation to the closed loop system stability, the achieved current decoupling degree and the transient response speed. Simulation and experimental results have been obtained in the case of a single-phase three-level Neutral Point Clamped ac-dc converter which validate the effectiveness of this new technique.