一种不依赖直流断路器的直流电网架构

提出一种不依赖直流断路器的直流电网架构和相应的控制保护策略。根据电压等级和端口特征,将直流电网划分为若干子系统,通过在子系统间的连接线上串入故障隔离设备,即可不依赖直流断路器,实现直流故障的就地处理,故障子系统的隔离及重启过程不影响健全子系统正常的功率传输。相应的功率调节策略和站间通信分层设计方案,可以有效降低定电压控制换流站的过负荷风险及站间通信系统的复杂度。PSCAD/EMTDC环境下的仿真结果验证了所提出的直流电网和对应控制保护策略的有效性。

Design of DC power grid without application of DC breaker

A DC power grid without application of DC breaker and its corresponding control and protection strategy are proposed. According to the voltage level and port characteristics, the DC power grid is divided into several sub-systems. By connecting the fault isolation equipment in series on the connecting line between the sub-systems, the DC fault can be handled locally without the help of DC breakers. The normal power transmission of perfect subsystem is not affected by the isolation and restart process of the fault sub-system. Relevant power regulation strategy and hierarchical design scheme of inter-station communication can effectively reduce the overload risk of constant voltage control converter station and the complexity of inter-station communication system. Based on PSCAD/EMTDC platform, the efficiency of the proposed DC grid and its corresponding control and protection strategy is validated by the simulative results.