高电压技术2018，Vol.44Issue(2)：388-394,7.DOI:10.13336/j.1003-6520.hve.20180131007
基于串联晶闸管强迫过零关断技术的混合式高压直流断路器
Hybrid HVDC Circuit Breaker Based on Series-connected Thyristors with Forced Zero Crossing Technique
摘要
Abstract
To improve the interruption capability and reduce the semiconductor cost of the hybrid DC circuit breaker,we proposed a new hybrid DC circuit breaker topology with bidirectional interruption based on forced zero crossing series-connected thyristors technique.By analyzing the breaking principle,we derived the parameters of voltage balancing circuit for the series-connected thyristors and diodes valves during the reverse recovery stage.Then,taking a 10 kV prototype for example,we carried out the devices selection and parameters design of the main and transfer branch.At last,a 10 kV DC breaker principle prototype and its test circuit were set up.The study results show that,in normal operation,the mechanical switch and small amount of series-connected full-controlled devices in main branch handle the low conduction loss.In case of interruption,the fault current is commutated to thyristors valve,and the current of thyristors valve is forced to zero by injecting current inversely for turning offthyristors.At last the inductive energy is dissipated by the energy absorbing branch.The principal prototype breaks the short current of 8.8 kA peak value under 10 kV voltage where the interruption time is less than 3 ms.The voltage rating and fault current withstanding capability of the breaker can be easily improved by adjusting the series-connected number and type of the semiconductor devices in the transfer branch.The diode valves can suppress the over-voltage of thyristor devices during reverse recovery under the high current interruption transient condition to decrease the risk of damage for thyristors.There is no need to adjust triggering time and match parameters for thyristors in series during the commutation and interruption stage of the hybrid breakers.In conclusion,the proposed hybrid DC breaker has the short-circuit fault fast cleating capability,so it is more suitable for the practical project of the future flexible high-voltage DC grid.关键词
混合式/断路器/串联/晶闸管/高压直流/电压源换流器Key words
hybrid/circuit breaker/series-connected/thyristor/high voltage direct current/voltage source converter引用本文复制引用
封磊,苟锐锋,杨晓平,王江涛,李超,卓放..基于串联晶闸管强迫过零关断技术的混合式高压直流断路器[J].高电压技术,2018,44(2):388-394,7.基金项目
国家重点基础研究发展计划(973计划)(2015CB251001 （973计划）
2015CB251004).Project supported by National Basic Research Program of China(973 Program) (2015CB251001,2015CB251004). （973 Program）
