多棒极型触发真空开关触发特性  

Triggering Characteristics of Multi-Electrode Type Triggered Vacuum Switch

作　　者：李化[1] 龙兆芝[1] 林福昌[1] 胡晓斌[1] 何正浩[1] 李文婷[1] 王蕾[1] 

机构地区：[1]华中科技大学电气与电子工程学院,武汉430074

出　　处：《电工技术学报》2009年第11期61-67,共7页Transactions of China Electrotechnical Society

摘　　要：主要研究多棒极型触发真空开关(TVS)的触发特性及其影响因素。研究表明,真空开关的触发时延主要由导通时延决定,增加触发电流的幅值和陡度(di/dt)可减小TVS的导通时延及其分散性。脉冲变压器直接触发TVS,可通过减小变压器漏感、提高触发电容的充电电压或增加触发电容电容量来降低导通时延及其分散性,但触发电容增加到一定值后对增加触发能量无帮助,没有必要继续增加。变压器直接触发方式可使导通时延减小至4μs左右,但分散性较大,且存在较小的触发回路电流导致的触发极熄弧现象。在脉冲变压器直接触发回路的基础上设计并研究了两种改进的触发回路:一种为脉冲变压器匹配续流回路,TVS导通时,通过续流回路的充电电容续流可使触发电流达kA级,导通时延减小至2～4μs,由于回路结构复杂,受到杂散参数影响,触发电流的幅值和陡度受到限制;一种为改进的触发回路,在触发极和阴极两端直接并接电容,导通时延可保持在1μs之内。最后研究并确定了并接电容选取依据和取值区间;对触发电压较小的TVS可在并接电容和触发极之间串联间隙,增大电容的充电电压和触发极能量,达到TVS可靠、精确触发的目的。The paper mainly studies a kind multi-electrode type triggered vacuum switch （TVS） and its trigger characteristics. The research first indicated that the trigger delay time was mainly decided by conduction delay time of TVS. And the increase of amplitude and steepness of triggered current can decrease the trigger delay time and its jitter. In the pulse transformer direct trigger mode, by reducing the leakage inductance of transformer, increasing the charging voltage or capacitance of trigger circuit capacitor could decrease conduction delay time and its jitter. But the trigger capacitance could not be continuously enlarged for a limitation of trigger energy with the capacitance keeping rise. The conduction delay time can be decreased to about 4μs. And the shortcoming of direct trigger mode is the large jitter and an easy-arc-extinguished phenomenon brought from a small triggered current for none infinite small leakage inductance. Two other kinds of trigger circuits were designed and discussed on the base of pulse transformer direct trigger mode： ① Matching a continuous-flow current circuit to pulse transformer trigger circuit. The trigger current could be enlarged and uninterrupted by the discharge of capacitor in continuous-flow current circuit. In this mode, the trigger current could increase to magnitude of kA and conduction delay time decreased to 2-4μs. And amplitude and steepness of trigger current is limited by the influencing of stay parameters in complex circuit.② Improved circuit based on pulse transformer trigger circuit. By directly paralleling a capacitor between the trigger electrode and cathode, the conduction delay time could be hold on within 1μs stably wltn a small jitter. At last, the choice of maximum and minimum value of paralleled capacitor was then identified by theoretical analysis and experimental study of trigger characteristics of TVS. A more reliable and accurate trigger mode could be achieved by installing a series air gap between paralleled capacitor and trigger electrod

关 键 词：触发真空开关 触发电流 漏感 续流回路 导通时延 

分 类 号：TM56[电气工程—电器]