基于智能软开关与联络开关并联的柔性配电网互联结构与控制技术研究

Research on Interconnection Structure and Control Technology of Flexible Distribution Network Based on Soft Open Point in Parallel With Interconnection Switch

用智能软开关(soft open point,SOP)替代配电网传统联络开关,可提高配电网可控性、灵活性与可再生能源接纳能力,实现区域经济运行。与传统联络开关相比,SOP成本高昂、占地面积大,不考虑转供电工况时可通过规划算法优化SOP选点与容量,降低其综合成本。然而联络开关主要功能是转供电,若作为替代装置的SOP不满足该需求,其推广应用必然受限。为此,该文提出基于SOP与联络开关并联的配电网柔性互联方案,兼顾了SOP经济规划与转供电需求,降低了SOP转供电的附加成本,支撑了SOP在配电网的规模化应用。同时,基于该方案提出一种平滑切换控制策略,以实现SOP控制模式的无缝切换和联络开关无相差合闸,降低转供电过程对SOP的电压电流冲击。

The soft open point(SOP)are used to replace the traditional interconnection switch in distribution network,which can improve the controllability,flexibility and renewable energy capacity of distribution network,and realize economic operation of regional distribution network.Compared with the traditional interconnection switch,SOP is expensive and occupies a large area.The location and capacity of SOP can be optimized by planning algorithm to reduce its comprehensive cost without considering the condition of load transfer.However,the main function of interconnection switch is load transfer,if this demand cannot be met by SOP,the popularization and application of SOP will be limited.Therefore,a flexible interconnection scheme of distribution network based on SOP in parallel with interconnection switch was proposed,considering the economic planning and the demand of load transfer,to reduce the additional cost of load transfer from SOP,and support the large-scale application of SOP in distribution networks.Based on this scheme,a smooth switching control strategy was proposed to realize the seamless switching of SOP control mode and no phase difference closing of parallel interconnection switch,thus reducing the voltage and current surge on SOP in the process of load transfer.