常规直流工程送端柔性化应用方案研究

Research on Flexible Application Schemes for Sending-end System in LCC-HVDC

自“双碳”目标提出后,我国能源和电力工业发生深刻变革,特别是促进了新能源的高速发展。目前,已投运的常规直流工程日内功率调节频次有限,送电曲线与新能源出力曲线匹配性较差,必须依托较大规模的火电、水电等稳定电源调峰,才能满足电力电量外送需求,限制了新能源输电比重的进一步提升。结合柔性直流输电技术特点,提出常规直流工程柔性化应用方案,其中包括柔性化运行方案、柔性化改造方案及构建多端混合直流方案,可以有效增强常规直流工程运行灵活性,充分发挥跨区输电通道新能源广域优化配置作用,为在运常规直流工程柔性化应用提供方案。

After the proposal of“dual carbon”target,the energy and the power industry has undergone profound reform in China,especially promoting the rapid development of new power.At present,the power adjustment times of the existing line commutated converterbased high voltage direct currentl(LCC-HVDC)projects in one day are limited,and the matching between the LCC-HVDC power transmission curve and the new power generation curve is poor,therefore large-scale stabilized power supplies such as coal-fired power plants and hydropower plants are needed to satisfy the transmission demand of electric power and quantity,which will restrict the increase of the renewable energy transmission proportion.Based on the technical features of voltage source converterbased high voltage direct current(VSC-HVDC),the flexible application schemes for sending-end system in LCC-HVDC are proposed,including the flexible operation scheme,the flexible retrofitting scheme,and the hybrid HVDC scheme,in order to improve the adaptability of LCC-HVDC project and make full use of cross-district transmission capacity,which will provide reference for the further development direction of the existing LCC-HVDC projects.