It is difficult to detect and extinguish direct current(DC)arc in power electronics systems,and the arc could easily lead to a fire and cause great damage to surrounding equipment.A DC arc generation simulation unit i...It is difficult to detect and extinguish direct current(DC)arc in power electronics systems,and the arc could easily lead to a fire and cause great damage to surrounding equipment.A DC arc generation simulation unit is established,in which DC series arcs are generated by dragging the moving electrode away from the fixed one with the help of the stepper motor.In addition,a ferrite rod antenna is used to receive the electromagnetic radiation signals induced by the arcs.Based on experiments using the unit,the general characteristics of DC arc,including the pulse characteristics of arc current and source output in corresponding time window,and the frequency-domain characteristics of arc current,are studied.With discussion on three detection methods,it is concluded that the variation of current and voltage of arc,the spectrum of the arc current during the discontinuous intervals and the radiating electromagnetic signal are all features that can be adopted for detecting DC series arc.Therefore,a synthetic judgment method is suggested for further study.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
基金Project supported by International Cooperation Project in Shaanxi Province of China(2012KW-01)
文摘It is difficult to detect and extinguish direct current(DC)arc in power electronics systems,and the arc could easily lead to a fire and cause great damage to surrounding equipment.A DC arc generation simulation unit is established,in which DC series arcs are generated by dragging the moving electrode away from the fixed one with the help of the stepper motor.In addition,a ferrite rod antenna is used to receive the electromagnetic radiation signals induced by the arcs.Based on experiments using the unit,the general characteristics of DC arc,including the pulse characteristics of arc current and source output in corresponding time window,and the frequency-domain characteristics of arc current,are studied.With discussion on three detection methods,it is concluded that the variation of current and voltage of arc,the spectrum of the arc current during the discontinuous intervals and the radiating electromagnetic signal are all features that can be adopted for detecting DC series arc.Therefore,a synthetic judgment method is suggested for further study.
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。
