Control Scheme of ±800kV/10000MW HVDC Transmission System for Large-Scale Renewable Energy Bases in Gobi Areas

Developing large-scale renewable energy bases is the key task in China’s 14th Five-Year Plan of modern energy systems. Aiming at transmitting large-scale wind power and photovoltaic power in the Gobi areas, two topologies suitable for ±800kV/10000MW HVDC transmission system are studied, namely wind-photovoltaic-bundled three-terminal MMC-HVDC system and heterogeneous series and parallel HVDC system with multiple DC voltage levels. Then, the voltage/power balance control between converters are analyzed in detail, and respective control strategies of multiple converters in the HVDC system are designed. Based on this, the overall control schemes of the two topologies are proposed. Finally, the feasibility of the proposed control strategies are verified using PSCAD/EMTDC.