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.
Study of Current-limited DC Transformer Topology and Its Transient Characteristics
The core component of the energy router is a dual active bridge(DAB)DC transformer,for which the current rise rate is fast,and the peak value is large during short-circuit faults,leading to the problem of blocking the power electronics inside the DAB.This paper presents a DC transformer with a current-limiting type structure.The current limiting device is structured as a single-phase rectifier bridge connected from the DAB high-voltage side H-bridge and then connected to the current limiting inductor at the output port.When a short-circuit fault occurs in the DC system,the current-limiting DC transformer uses a Hybrid control algorithm to rectify the current,provide a clamp voltage for the current-limiting inductor,limit the peak value of the fault current,and cooperate with the circuit breaker to achieve arc-free opening and closing,which avoids latching of the power electronics in the DAB and quickly achieves fault current limiting and isolation.The model of a limiting DC transformer based on a 10kV/750V DC transformer is built in the simulation system,and the simulation results show the effectiveness and feasibility of a limiting DC transformer with a circuit breaker to realize fault current limiting and isolation.
current limiting DC transformerhybrid control algorithmscircuit breaker arc-free openingfault limiting and isolation
万方数据
维普
