In this paper, we investigated the di/dt capability and the turn-on action of conventional thyristors (including common thyristor and GTO) under short pulse conditions. Although the common thyristor is proven to be not adequate for pulse application, the GTO behaves excellently and it exhibits the potential of being operated in the case of much higher di/dt and pulse current than its rated values. Multi-cell PSpice simulation model of GTO was developed to evaluate influence factors of current distribution in thousands units of the GTO. It was found that forward transport time (TF) of excess carriers flowing through base region in each unit mainly determines the current distribution. If some unit has smaller TF, it will bear larger current compared with others in the turn-on process and thus has the risk of overheating. The use of magnetic switch in series with GTO can greatly reduce the power dissipation in the process and guarantee the GTO''s safe operation. Our tests have originally resulted in a maximum di/dt of 6 kA/μs for a 10-μs half-sine wave current pulse of 17.3 kA amplitude by using a GTO, whose rated RMS on-state current is 1500 A and di/dt capability is 800 A/μs. The measurements show that turn-on losses and conduction losses are less than 0.5 J.
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机译：在本文中，我们研究了在短脉冲条件下常规晶闸管（包括普通晶闸管和GTO）的di / dt能力和导通作用。尽管事实证明普通晶闸管不适合脉冲应用，但GTO表现出色，并且在di / dt和脉冲电流比其额定值高得多的情况下，它具有工作的潜力。开发了GTO的多单元PSpice仿真模型，以评估数千个GTO中电流分布的影响因素。发现在每个单元中流过基极区的多余载流子的前向传输时间（TF）主要决定电流分布。如果某些单元的TF较小，则在开启过程中它将承受比其他单元更大的电流，因此有过热的风险。与GTO串联使用电磁开关可以大大减少过程中的功耗，并确保GTO的安全运行。我们的测试最初通过使用GTO（额定RMS导通电流为1500 A和di / dt）对一个17.3 kA振幅的10μs半正弦波电流脉冲产生了最大di / dt为6 kA /μs。容量为800 A /μs。测量表明导通损耗和传导损耗小于0.5J。
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