Table 6 Topology of DR-HVDC for OWFs
Topology types | Benefits | Challenges | Feasibility |
|---|---|---|---|
DR- series MMC | •  AC voltage control is enhanced •  Investment cost, power losses, and volume are reduced •  Reliability is improved | •  Power rating of MMC •  Line maintenance | *** |
DR-parallel MMC | •  Volume, weight, and cost are reduced •  Harmonic currents are reduced •  Active power flow distribution is improved | •  MMC-HVDC link overloaded •  DR-HVDC overloaded | *** |
DR(MERS)-CSI [125] | •  MPPT is achieved •  Controllability and robustness are enhanced Generator voltage utilization is improved | •  Cost of DR •  Equipment maintenance | ** |