适用于高压直流电网的直流开关场

Research on Direct-current Switchyard Suitable for High-voltage Direct-current Grids

基于电流转移原理的混合式直流断路器在应用于多线路的高压直流电网时一次建设成本过高,经济性差,而共用＂主断开关＂的直流开关场则是解决上述问题的有效途径。不同的直流开关场拓扑具有不同的特点,对其进行归纳、分析和比较将有助于加深对直流开关场拓扑的认识并为工程应用中的选型提供指导。为此根据电流转移方式将现有直流开关场分为3类：选择转移型、单转移型和全转移型,并对3类直流开关场的拓扑结构和工作原理分别进行介绍,归纳了未来高压直流电网对直流开关场的基本要求,对各类直流开关场重合闸功能、对快速机械开关的失灵保护功能、动作复杂程度、经济性进行了对比分析,进而得出结论：现阶段全转移型直流开关场是高压直流电网最有应用前景的直流开关场。最后还给出了适用于高压直流电网的直流开关场的相关研究建议。

Hybrid DC circuit breakers, based on current transfer principle, are uneconomical for the high construction cost when they are applied in multi-line high-voltage DC grids, and that DC switchyard shares ＂main breaker＂ is an effective way to solve the above problem. Different topologies of DC switchyard have different characteristics. Summarizing, analyzing, and comparing characteristics of different topologies of DC switchyard will help deepen the understanding of DC switchyard and provide a guidance for selection of engineering applications. In this paper, the proposed DC switchyard is divided into three types, based on three different kinds of current transfer modes of DC switchyard： selective transfer, single transfer, and all transfer,The topologies and working principles of different types of DC switchyard are introduced, and the basic requirements for the DC switchyard in the future high-voltage DC networks are summarized. Reclosing function, failure protection for ultra fast disconnector, complexity of action and economy of different kinds of DC switchyard are also compared and analyzed. It is concluded that transfer-type DC switchyard is the most promising DC switchyard in high-voltage DC power grids. Finally, the relative research recommendations of DC switchyard are given.