大规模新能源超远距离送出的柔性直流系统集成设计方案OA北大核心CSTPCD

Large-scale renewable energy transmission from desert,Gobi and wilderness to load centers is critical measure to achieve the goals of"Carbon Peak and Carbon Neutrality".Two large-scale renewable energy ultra-long-distance transmission schemes are introduced,including line commutated converter based high voltage direct current(LCC-HVDC)and voltage source convert based high voltage direct current(VSC-HVDC).The two schemes are compared in terms of their applicable scenarios,overvoltage,voltage and reactive power adjustment capabilities,and economy,to highlight their respective advantages and disadvantages.VSC-HVDC is superior in terms of technology and economy.An integrated design scheme of±800 kV/10 GW four-terminal VSC-HVDC system for 10 gigawatt renewable energy ultra-long-distance transmission is proposed,which includes the electrical main wiring,main circuit parameters,coordinated control strategy,and the configuration of AC/DC choppers.Key technologies such as bipolar single-valve and high-low valve scheme selection,AC voltage coordinated control of multi-valve at the sending end,and DC voltage balance control of high-low valve are studied,and the configuration scheme and switching strategy of the configuration of AC/DC choppers are proposed.The effectiveness of the HVDC transmission system scheme is verified through electromagnetic transient simulation.