Provision of Synthetic Inertia by Alternate Arm Converters in VSC-HVDC Systems

This paper demonstrates the integration of virtual synchronous generator (VSG) control into alternate arm converters (AAC), enabling the converter to provide inertia. Combined with frequency and voltage primary droop control, the converter can further participate into the regulation of the grid in the event of frequency or voltage disturbance. This can be realized by absorbing or releasing the energy from the DC-link of AAC terminal. Integrating VSG control, following the regulation of active and reactive power output, the overcurrent and voltage ripples of AAC are limited and acceptable during the disturbance period. A case study of a 800 MW VSG-based AAC system is tested on Simulink/Plecs to validate the AAC response with VSG control.