Research on an AC/DC networking and transmission scheme for large-scale onshore hydro-wind-solar integrated bases

Abstract

The large-scale onshore hydro-wind-solar integrated bases in southwest China have great development potential， and it is necessary to determine a suitable scheme for power transmission to the eastern load center. In view of the boost collection inside the wind and solar energy base and problems of the traditional AC scheme such as reactive power and limited transmission distance， the paper studies the AC/DC networking and transmission scheme for large-scale onshore hydro-wind-solar integrated bases. First， it introduces the scheme from the aspects of the multi-voltage level DC system with the integration of photovoltaic and wind power and island transmission system of hydropower， and schemes for DC transformers of all levels are introduced. Then， the DC voltage control strategy and fault ride-through control strategy are expounded. Finally， based on PSCAD/EMTDC， a simulation model of AC/DC networking and transmission system for a 15，000 MW large-scale onshore hydro-wind-solar integrated base transmission is built， and the feasibility of the proposed scheme is verified.

Keywords

• hydro-wind-solar integrated bases
• ac/dc networking
• dc transformer
• control and protection strategy