中压固态复合开关切除电容器组的建模与分析  

Modeling and Analysis of Medium-voltage Solid-state Hybrid Switch for Turning-off Capacitor Bank

作　　者：李卫国 肖湘宁 罗应立 邱宇峰 崔学深 

机构地区：[1]新能源电力系统国家级重点实验室(华北电力大学),北京市昌平区102206 [2]国网智能电网研究院,北京市昌平区102206

出　　处：《中国电机工程学报》2013年第3期163-170,2,共8页Proceedings of the CSEE

摘　　要：以真空断路器与晶闸管阀并联构成的中压固态复合开关切除电容器组的研究内容,主要是对电容器组负载电流由真空断路器至晶闸管阀之间电流转移这一暂态过程进行解析分析。首先基于真空断路器分段线性化电弧伏安特性曲线,并结合等效电路构建电流转移数学模型;然后据此推导出中压固态复合开关切除电容器组电流和晶闸管阀端电压解析解;最后据此可以得出晶闸管阀组最佳触发时刻、晶闸管阀组设计参数以及电流转移暂态过程中电流冲击程度。因为实现了由真空断路器至晶闸管阀的电流转移,所以电容器组在晶闸管阀电流自然过零时刻被切除,彻底克服固定电容器(fix capacitor,FC)开关分闸时造成的开关重燃和操作过电压。中压固态复合开关切除电容器负载暂态性能与晶闸管开关电容器(thyristor switch capacitor,TSC)性能基本一致,但却实现了紧凑化、低成本和高可靠性设计。利用仿真和现场录波波形验证了技术可行性。In a medium-voltage solid-state hybrid switch（MV SSHS） which is made of the vacuum breaker and the thyristor valve in parallel connection,the transient process of switching off capacitor load is that the capacitor load current transfers from the vacuum breaker to the thyristor valve,then it can be cut off at the crossing zero point.Transient parse of the capacitor current and the voltage of thyristor valve was deduced based on the mathematics model which consist of dynamic snubber circuits of the thyristor valve,the piecewise linear voltage-current characteristic curve of arc,the series-wound reactor and capacitor.Accordingly the following result can be drawn： the optimal trigger time of the thyristor valve and the theoretical foundation for thyristor valve design are established in order to transfer the current from vacuum breaker to the thyristor valve.It can overcome reignition and overvoltage by the current of capacitor switched off at the time of the crossing zero point.Transient capability of the middle-voltage solid-state hybrid switch is similar to TSC（thyristor switch capacitor）,but SSFC has advantages of compact,low cost and high reliability.The validity can be verified by Matlab simulation and engineering tests.

关 键 词：真空断路器 固态复合开关 电弧数学模型 晶闸管阀 电容器组 电流转移 

分 类 号：TM5[电气工程—电器]