在进行某变电站新投运设备(新安装一年)的例行预防性试验时,发现其中一台500k V HGIS断路器在进行合闸时间测试时出现三相不同期现象。随后对该断路器进行机械特性和电气特性两方面的测试,并根据测试结果对出现该现象产生的原因进行了...在进行某变电站新投运设备(新安装一年)的例行预防性试验时,发现其中一台500k V HGIS断路器在进行合闸时间测试时出现三相不同期现象。随后对该断路器进行机械特性和电气特性两方面的测试,并根据测试结果对出现该现象产生的原因进行了简单分析。展开更多
In this work, the field plate termination is studied for Ga2O3Schottky barrier diodes(SBDs) by simulation. The influence of field plate overlap, dielectric material and thickness on the termination electric field dist...In this work, the field plate termination is studied for Ga2O3Schottky barrier diodes(SBDs) by simulation. The influence of field plate overlap, dielectric material and thickness on the termination electric field distribution are demonstrated.It is found that the optimal thickness increases with reverse bias increasing for all the three dielectrics of SiO2, Al2O3, and HfO2. As the thickness increases, the maximum electric field intensity decreases in SiO2and Al2O3, but increases in HfO2.Furthermore, it is found that SiO2and HfO2are suitable for the 600 V rate Ga2O3SBD, and Al2O3is suitable for both600 V and 1200 V rate Ga2O3SBD. In addition, the comparison of Ga2O3SBDs between the SiC and GaN counterpart reveals that for Ga2O3, the breakdown voltage bottleneck is the dielectric. While, for SiC and GaN, the bottleneck is mainly the semiconductor itself.展开更多
文摘在不同的温度条件下,采用实验生态学方法,研究了氨氮对不同年龄阶段泥蚶的急性毒性试验。经双因子方差分析表明:氨氮浓度、温度以及氨氮浓度和温度的相互作用均极显著地影响二龄和三龄泥蚶96 h的成活率。在24℃、28℃、32℃时,总氨氮对二龄泥蚶的96 h LC50分别为348.40、312.99、219.06 mg/L,SC分别为34.84、31.30、21.91 mg/L;总氨氮对三龄泥蚶的96 h LC50分别为681.25、443.20、285.84 mg/L,SC分别为68.13、44.32、28.58 mg/L。
基金Project supported by the Research Fund of Low Cost Fabrication of GaN Power Devices and System Integration,China(Grant No.JCYJ20160226192639004)the Research Fund of AlGaN HEMT MEMS Sensor for Work in Extreme Environment,China(Grant No.JCYJ20170412153356899)the Research Fund of Reliability Mechanism and Circuit Simulation of GaN HEMT,China(Grant No.2017A050506002)
文摘In this work, the field plate termination is studied for Ga2O3Schottky barrier diodes(SBDs) by simulation. The influence of field plate overlap, dielectric material and thickness on the termination electric field distribution are demonstrated.It is found that the optimal thickness increases with reverse bias increasing for all the three dielectrics of SiO2, Al2O3, and HfO2. As the thickness increases, the maximum electric field intensity decreases in SiO2and Al2O3, but increases in HfO2.Furthermore, it is found that SiO2and HfO2are suitable for the 600 V rate Ga2O3SBD, and Al2O3is suitable for both600 V and 1200 V rate Ga2O3SBD. In addition, the comparison of Ga2O3SBDs between the SiC and GaN counterpart reveals that for Ga2O3, the breakdown voltage bottleneck is the dielectric. While, for SiC and GaN, the bottleneck is mainly the semiconductor itself.