In the modular multilevel converter (MMC) based high voltage direct current (HVDC) transmission system, the high-frequency negative damping effect of the MMC output impedance induces high frequency resonances. The existing active damping controls, such as the virtual series impedance, change the range of high-frequency negative damping effects, thereby suppressing the high-frequency resonances (HFRs). However, it can only be applied to the single operating condition of AC power grid because the single damping controller cannot effectively resha...
