Tuning of resonant controllers applied to the current control of Voltage-Source Converters

The current control of a Voltage-Source Converter (VSC) requires continuous innovation due to the increasing demands on the permissible level of harmonics in the mains. Nowadays, one of the most used techniques is the resonant control, which can be implemented in various ways, all having in common that they have a theoretical infinite gain at the resonant frequency. Four of those ways are discussed in this paper, comparing their results when applying them to the current control of a VSC. Two of them were originally used to implement the voltage control of a converter and they have now been applied to the current control of a grid-connected power converter. Simulation and experimental results are provided in order to compare their performance in a grid whose harmonic content includes harmonic sixth, analyzing typical control parameters such as settling time, maximum overshoot and steady-state error.