Harmonic Power Detection-Based Adaptive Resonance Suppression for Power Converters

Converter-driven resonance issues are challenging to power system stability and security, due to the rapid increase in renewable energy and power converters. Research on this topic focuses on impedance analysis, and is devoted to eliminating converter negative damping from the view of the phase angle. However, two factors limit the application of this method: 1) positive damping characteristics cannot ensure the grid connection stability of new converters, because the grid might already include many negative damping devices; and 2) converters from different vendors might have different negative damping inducement, and hence a general solution to resolve their negative damping issues is difficult. To overcome these issues, this article proposes a general stability control concept for power converters from the view of the impedance magnitude. With the ability of wideband harmonic control, power converters can accurately follow grid perturbations and work as a “zero-harmonic” source in a wide band. The improved converter can be stably connected to different grids with no effects on the resonance characteristics of the existing grid. The effectiveness of the proposed method is validated by electromagnetic transient simulations in MATLAB/SIMULINK.