Harmonic Stability of Grid-connected Voltage Source Converters Considering Parameter Sensitivity

This paper deals with the problem of harmonic stabilization based on the parametric sensitivity of voltage source converters (VSCs) operating in parallel. In wind farms and HVDC systems, it needs to take into account the performance of inner current loop or outer voltage loop with the change of the system damping. Uncertainty parameter of controllers can affect the possibility to damp oscillations. This paper proposes a new way using a controlled voltage source to replace VSCs as well as using eigenvalue analysis method for assessing undesirable effects of variable controller parameters on the non-harmonic excitation. Analyzing the simulation results of a representative system in MATLAB/Simulink demonstrate the effectiveness of the proposed method in clarifying harmonic interaction of parallel VSC controllers.