Analysis of Grid-Connected VSCs Subject to Voltage Harmonic Disturbances: Prediction and Design Tool of Resonant Controllers

The influence of current and voltage harmonics in the power quality of electrical facilities is currently an important topic in discussion. Considering that in Voltage Source Converter (VSC) applications it is common to utilize resonant controllers to mitigate characteristic current harmonics, this work proposes a methodology to allow the tuning of resonant controllers through a power quality criterion during the design process, enabling the designer to select between harmonic content and stability. The disturbance rejection model that relates the output harmonic currents with the grid voltage harmonics is utilized as basis for the methodology, also providing an analytical calculation of the resonant controller gain according to the imposed harmonic limitations, both for VSCs with regular L as with LCL output filters. Simulations and experiments validate the proposal.