直流系统的故障隔离是保证直流系统稳定运行的重要技术。针对传统故障隔离策略对直流断路器(direct current circuit breaker, DCCB)的性能要求较高的问题,提出了一种利用柔性限流装置(flexible current limiting device,FCLD)与DCCB协...直流系统的故障隔离是保证直流系统稳定运行的重要技术。针对传统故障隔离策略对直流断路器(direct current circuit breaker, DCCB)的性能要求较高的问题,提出了一种利用柔性限流装置(flexible current limiting device,FCLD)与DCCB协同动作的故障隔离策略。首先,研究了直流系统永久性故障和瞬时性故障情况下FCLD与DCCB的协同作用机理。其次,分析考虑FCLD电流抑制作用下DCCB开断过程的电弧暂态特性。最后,在Matlab/Simulink平台中进行仿真,验证所提协同策略的可行性。结果表明:FCLD可有效抑制DCCB的开断电弧;基于所提故障隔离策略,直流系统可在瞬时故障情况下实现平稳穿越,永久故障情况下实现DCCB的无弧开断。该策略降低了直流系统故障隔离过程中对DCCB的开断要求,提升了直流系统的故障穿越能力。展开更多
能量路由器的核心元件为双有源桥(dual active bridge,DAB)直流变压器,针对其短路故障时电流上升速率快,峰值大,导致DAB内部电力电子器件闭锁的问题,该文提出一种具有限流型结构的直流变压器,限流装置结构为从DAB高压侧H桥连接单相整流...能量路由器的核心元件为双有源桥(dual active bridge,DAB)直流变压器,针对其短路故障时电流上升速率快,峰值大,导致DAB内部电力电子器件闭锁的问题,该文提出一种具有限流型结构的直流变压器,限流装置结构为从DAB高压侧H桥连接单相整流桥,再与输出端口的限流电感相连。当直流系统发生短路故障时,限流型直流变压器采用混合控制算法进行整流,为限流电感提供钳位电压,限制故障电流的峰值,并与断路器配合实现无弧开断,该方法避免DAB中电力电子器件发生闭锁,快速实现故障限流和隔离。在仿真系统中搭建了基于10kV/750V直流变压器的限流型直流变压器的模型,仿真结果表明限流型直流变压器与断路器配合实现故障限流和隔离的有效性和可行性。展开更多
High voltage direct current(HVDC)systems are efficient solutions for the integration of large-scale renewable energy sources with the main power grids.The rapid development of the HVDC grid has resulted in a growing i...High voltage direct current(HVDC)systems are efficient solutions for the integration of large-scale renewable energy sources with the main power grids.The rapid development of the HVDC grid has resulted in a growing interest in DC circuit breakers(DCCBs).A fast and reliable circuit breaker is a necessary requirement in the development of large scale HVDC grids.This paper provides a comprehensive review and survey of the HVDC CBs and discusses potential research directions.Operational principles and the main features of various DCCBs are described and their merits and shortcomings are also highlighted.展开更多
文摘直流系统的故障隔离是保证直流系统稳定运行的重要技术。针对传统故障隔离策略对直流断路器(direct current circuit breaker, DCCB)的性能要求较高的问题,提出了一种利用柔性限流装置(flexible current limiting device,FCLD)与DCCB协同动作的故障隔离策略。首先,研究了直流系统永久性故障和瞬时性故障情况下FCLD与DCCB的协同作用机理。其次,分析考虑FCLD电流抑制作用下DCCB开断过程的电弧暂态特性。最后,在Matlab/Simulink平台中进行仿真,验证所提协同策略的可行性。结果表明:FCLD可有效抑制DCCB的开断电弧;基于所提故障隔离策略,直流系统可在瞬时故障情况下实现平稳穿越,永久故障情况下实现DCCB的无弧开断。该策略降低了直流系统故障隔离过程中对DCCB的开断要求,提升了直流系统的故障穿越能力。
文摘能量路由器的核心元件为双有源桥(dual active bridge,DAB)直流变压器,针对其短路故障时电流上升速率快,峰值大,导致DAB内部电力电子器件闭锁的问题,该文提出一种具有限流型结构的直流变压器,限流装置结构为从DAB高压侧H桥连接单相整流桥,再与输出端口的限流电感相连。当直流系统发生短路故障时,限流型直流变压器采用混合控制算法进行整流,为限流电感提供钳位电压,限制故障电流的峰值,并与断路器配合实现无弧开断,该方法避免DAB中电力电子器件发生闭锁,快速实现故障限流和隔离。在仿真系统中搭建了基于10kV/750V直流变压器的限流型直流变压器的模型,仿真结果表明限流型直流变压器与断路器配合实现故障限流和隔离的有效性和可行性。
文摘High voltage direct current(HVDC)systems are efficient solutions for the integration of large-scale renewable energy sources with the main power grids.The rapid development of the HVDC grid has resulted in a growing interest in DC circuit breakers(DCCBs).A fast and reliable circuit breaker is a necessary requirement in the development of large scale HVDC grids.This paper provides a comprehensive review and survey of the HVDC CBs and discusses potential research directions.Operational principles and the main features of various DCCBs are described and their merits and shortcomings are also highlighted.
