Analysis of Onshore Synthetic Inertia and Primary Control Reserve Contributions of Alternating Current-Side Meshed Offshore Grids with Voltage-Source Converter and Diode Rectifier Unit High-Voltage Direct Current Connections

The increasing use of renewable energy sources in place conventional generation units is leading to a reduction onshore inertia and the development offshore wind park grids connected by multiple high-voltage direct current (HVDC) connections alternating (AC) grid. For AC-side meshed with voltage-source converter (VSC) diode rectifier unit (DRU) HVDC towards grids, this study focuses on energetic feasibility synthetic (SI) primary control reserve (PCR) contributions triggered locally at converters both connection types. To end, obstacles preventing for VSC mechanisms allowing DRU are identified first. Based these findings, article proposes an enhancement controls that continuously active allows all types without using communication requiring only minimal system knowledge. Additional simulations confirm that, although active, operational performance normal grid operation its robustness against faults not affected.