面向新型电力系统的直流输电换流器统一拓扑架构

Unified High Voltage Direct Current Converter Topology Dedicated for New Power Systems

新型电力系统对直流输电技术提出了更高需求。该文首先介绍了直流输电的发展历程,并基于新型电力系统发展带来的挑战分析了常规直流输电和柔性直流输电两类技术的优势和不足。为此,从换流器拓扑入手,突破同构串联和异构并联两种常见拓扑架构,以晶闸管换流器和模块化多电平换流器为基础,提出了面向新型电力系统的异构串联型换流器统一拓扑架构。从运行区间、无闭锁故障穿越等技术性能和经济性、易实现性等工程应用角度综合对比分析了多种结构的换流器,证明了异构串联型换流器的优越性。最后,介绍了异构串联拓扑架构的两种具体应用,指出了未来发展方向。

New power systems put forward higher demands for DC transmission technologies.Firstly,we briefly reviewed the development of HVDC power transmission.Based on the challenges resulting from developing the new power systems,we analyzed the advantages and disadvantages of conventional DC transmission and flexible DC transmission technologies.Then,based on thyristor converters and modular multilevel converters,we proposed a unified heterogeneous series converter topology for the new power systems,which breaks through the common homogeneous series topology and heterogeneous parallel topology.The advantages of the heterogeneous series converters were proved by comprehensive comparison and analysis of the converters of various structures from the aspect of technical performance such as the operation range,nonblocking fault ride-through capability and so on,and from the aspect of engineering application such as economy,ease of implementation and so on.Finally,two engineering applications were introduced and the future development directions of the heterogeneous series converters were summarized.