通过直流断路器切除故障是柔性直流电网中最具前景的故障隔离方法.目前,主断支路串联大量全控型电力电子器件的传统混合式直流断路器存在成本高、技术难度大等问题.文中提出一种基于晶闸管的电容换相式混合直流断路器(Thyristor Based Capacitor Commutation Hybrid DC Circuit Breaker,TCC-HDCCB)拓扑.该断路器通过晶闸管和电容配合完成双向故障换流、断流和自适应重合闸功能且利用直流系统本身对换相电容进行预充电,大大降低了造价和控制难度.文中首先介绍了TCC-HDCCB的拓扑结构、工作原理;然后给出了关键器件参数选取方法;最后在PSCAD/EMTDC4.5 软件平台中搭建TCC-HDCCB仿真模型,在单端和四端柔性直流电网中进行仿真验证,并从性能以及经济性与有关方案进行对比分析,验证方案的可行性.
Thyristor Based Capacitor Commutator Hybrid DC Circuit Breaker Topology
It is the most promising fault isolation method in flexible DC power network to remove faults by DC circuit breaker.At present,the traditional hybrid DC circuit breaker with a large number of fully controlled power electronic devices connected in series by main and branch has many problems such as high cost and technical difficulty.A Thyristor based Capacitor commutation hybrid DC circuit breaker topology(TCC-HDCCB)is proposed.The circuit breaker realizes the functions of two-way fault commutation,cut-off and adaptive reclosing through the combination of thyristor and capacitor,and uses the DC system itself to pre-charge the commutation capacitor,which greatly reduces the cost and control difficulty.In this paper,the topological structure and working principle of TCC-HDCCB are first introduced,and then the selection method of key device parameters is given.Finally,the simulation model of TCC-HDCCB is built in the software platform of PSCAD/EMTDC4.5,and the simulation verification is carried out in the single terminal and four terminal flexible DC power grid.The feasibility of the scheme is verified by comparing the performance and economy with the relevant schemes.
DC circuit breakerthyristorcapacitanceadaptive reclosingpre-chargeeconomy
NETL
NSTL
万方数据
