柔性直流配网直流变压器涌流机理分析与抑制  

Analysis and Suppression of Inrush Current Mechanism of DC Transformer in Flexible DC Distribution Network

作　　者：李唯草 吴晓颖 LI Weicao;WU Xiaoying(Wuhan Institute of Marine Electric Propulsion,Wuhan 430000;No.709 Canglong Avenue,Jiangxia District of Wuhan,Wuhan 430205)

机构地区：[1]武汉船用电力推进装置研究所,武汉430000 [2]武汉市江夏区,武汉430205

出　　处：《舰船电子工程》2022年第7期184-190,共7页Ship Electronic Engineering

摘　　要：多端互联柔直配电网是建立新型电力系统的重要载体。多端柔直配电网端口特性复杂、节点多,单端交流故障闭锁瞬间造成各端口潮流阶跃式波动,容易涌入阻抗小的直流变压器触发保护停机。论文依托大型实际工程建设以及运行中出现的技术难题,采用一种T接星型多端柔性直流配电网拓扑作为系统结构,建立以双端有源桥为单元的直流变压器的稳态模型,分析揭示了直流变压器存在潜在流通回路的涌流机理,综合分析了直流变压器参数设计依据。针对变压器瞬间涌流的问题,提出了一种H桥暂时性闭锁+DAB不闭锁抑制策略,通过DAB模块的电抗串入增强了涌流抑制能力,暂时性闭锁策略迅速解除提升系统运行可靠性。最后通过仿真和实际大型工程试验运行结果验证了论文方法的有效性和实用性,具有工程实用化价值。Although flexible DC distribution network is an important carrier to build a new power system,it has complex port characteristics and many nodes.The single terminal AC fault causes the power flow step fluctuation of each port,which is easy to rush into the DC transformer due to small impedance,triggering the protection shutdown.This paper takes a T-connected star type multi-terminal flexible DC distribution network topology as the system structure,establishes the steady-state model of the DAB based DC transformer,analyzes and reveals the inrush current mechanism.The design of DC transformer parameters is analyzed comprehensively.A suppression strategy of H-bridge temporary blocking and DAB not blocking is proposed.The over current sup⁃pression ability is enhanced by the reactance of DAB module in series,and the temporary blocking strategy is removed quickly to improve the system operation reliability.Finally,the effectiveness and practicability of the proposed method are verified by actual large-scale engineering test results,which has engineering practical value.

关 键 词：多端互联柔直配电网 直流变压器 涌流机理 暂时性闭锁 大型实际工程 

分 类 号：U46[机械工程—车辆工程]