外文翻譯---晶閘管的高能脈沖式開關(guān)特性

1、外文原文與譯文 外文原文與譯文High-Energy Pulse-Switching Characteristics of Thyristors AbstractExperiments were conducted to study the high energy, high dildt pulse-switching characteristics of SCR's with and without the amplifyin

2、g gate. High dildt. high-energy single- shot experiments were first done. Devices without the amplifying gate performed much better than the devices with the amplifying gate. A physical model is presented to describe th

3、e role of the amplifying gate in the turn-on process, thereby explaining the differences in the switching characteristics. The turn-on area for the failure of the devices was theoretically estimated and correlated with o

4、bservations. This allowed calculation of the current density required for failure. Since the failure of these devices under high dildt conditions was thermal in nature, a simulation using a finite-element method was pe

5、rformed to estimate the temperature rise in the devices. The results from this simulation showed that the temperature rise was significantly higher in the devices with the amplifying gate than in the devices without the

6、 amplifying gate. From these results, the safe operating frequencies for all the devices under high dildt conditions was estimated. These estimates were confirmed by experimentally stressing the devices under high di/dt

7、 repetitive operation. I. INTRODUCTION Recent innovations in semiconductor device designs and advances in manufacturing technologies have helped evolve high-power thyristors. These devices are designed to operate in a

8、 continuous mode for applications such as ac- to-dc power conversion and motor drives. Until recently, their application to high-power pulse switching was mostly unknown. One of the main reasons that has discouraged the

9、 use of thyristors for high-speed, high-energy switching is their low dildt rating. The limiting value of the dildt before damage occurs is related to the size of the initial turn-on area and the spreading velocity [I]

10、. Recent experimental results presented in [2]-[4] show that with increased gate device, SCR's and GTO's having highly interdigitated gate-cathode structures can reliably operate under high dildt conditions on a

11、 single-shot basis. Previously, SCR's have also been used for repetitive switching of 1 kA, 10 ps wide pulses having a dildt of about 10 000 Alps, at 500 and 800 Hz for a 10 h period [SI. It is reported in [6] that

12、 GTO modules (five devices in series) can block 11.5 kV and switch 4.5 kA pulses having a dildt of 2500 A/ks at frequencies of 100 Hz. Asymmetric devices, such as the ASCR's in a stack assisted by saturable inductor

13、s, of failure around the amplifying gate can be seen as a hot spot. All these results point to the fact that the conduction area near the amplifying gate region in the unshorted device is very small. This leads to an in

14、crease in current density in the device and, therefore, the instantaneous rise in temperature exceeds the threshold value for failure: about 1100°C [9]. TABLE1 SINGLE-SHOT EXPERIMENTAL RESUILSTSFig. 1. Typical (CH

15、1) and (CH2) switching waveforms of the unshorted A I AK Vdevice, CH1-1931 A/div, CH2-500 V/div, Timebase-100ns/div.111. ROLEOF THE AMPLIFYING GATE The results presented in the previous section show that the devices wit

16、hout the amplifying gate (shorted devices) better than the devices with the amplifying gate (unshorted devices). The typical switching waveforms of the unshorted and the shorted devices are shown in Figs. 1 and 2, resp

17、ectively. In the case of the unshorted device, the anode current rises to a certain value and remains at that value for about ns before rising further its peak value (when the resistance of the device reduces as a resu

18、lt of more turned-on area). This behavior is not seen when the shorted device is used for switching. The anode current switched by the shorted devices has a smooth rising edge. The dynamic resistance of the two devices