This paper analyzes the different discharge processes occurring at normal temperatures and high temperatures. The theoretical results show that the net charges in the streamer channel at normal temperatures are zero...This paper analyzes the different discharge processes occurring at normal temperatures and high temperatures. The theoretical results show that the net charges in the streamer channel at normal temperatures are zero, but they are positive at high temperatures so that the advancing field is reinforced more than that at normal temperatures. Therefore, the field required for streamer propagation is reduced at high temperatures. The sparkover voltage is largely reduced with increased temperature, which is influenced by the solid materials in the flame.展开更多
More and more high voltage transmission lines make use of rubber housed ZnO arresters in series with another air gap (for example, the insulator gap) as lighting protection elements. Many test results of ZnO arreste...More and more high voltage transmission lines make use of rubber housed ZnO arresters in series with another air gap (for example, the insulator gap) as lighting protection elements. Many test results of ZnO arresters protection performance show that this insulation arrangement is suitable for practical lines according to results based on only simple impulse voltage. This paper uses a composite voltage (switching impulse voltage/alternating voltage) to determine the air breakdown behavior of the conductor rod gap in series with the sphere gap. In the test, the switching impulse voltage is applied to the conductor while the alternating voltage is applied to the rod and one sphere and the other sphere is grounded. The results show that in some cases, the value of the U 50% sparkover voltage for the conductor rod gap with the composite voltage is nearly only half of that for just the simple impulse voltage.展开更多
The human body model（HBM） stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge,including current waveforms and peak current under varied stress voltage and d...The human body model（HBM） stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge,including current waveforms and peak current under varied stress voltage and device failure voltage.A new discharge model called the ＂sparkover-induced model＂ is proposed based on the results.Then,failure mechanism analysis and model simulation are performed to prove that the transient peak current caused by a sparkover of low arc impedance will result in the devices＇ premature damage when the potential difference between the no-connect metal cover and the chip exceeds the threshold voltage of sparkover.展开更多
文摘This paper analyzes the different discharge processes occurring at normal temperatures and high temperatures. The theoretical results show that the net charges in the streamer channel at normal temperatures are zero, but they are positive at high temperatures so that the advancing field is reinforced more than that at normal temperatures. Therefore, the field required for streamer propagation is reduced at high temperatures. The sparkover voltage is largely reduced with increased temperature, which is influenced by the solid materials in the flame.
文摘More and more high voltage transmission lines make use of rubber housed ZnO arresters in series with another air gap (for example, the insulator gap) as lighting protection elements. Many test results of ZnO arresters protection performance show that this insulation arrangement is suitable for practical lines according to results based on only simple impulse voltage. This paper uses a composite voltage (switching impulse voltage/alternating voltage) to determine the air breakdown behavior of the conductor rod gap in series with the sphere gap. In the test, the switching impulse voltage is applied to the conductor while the alternating voltage is applied to the rod and one sphere and the other sphere is grounded. The results show that in some cases, the value of the U 50% sparkover voltage for the conductor rod gap with the composite voltage is nearly only half of that for just the simple impulse voltage.
基金supported by the National Natural Science Foundation of China(No.60927006)
文摘The human body model（HBM） stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge,including current waveforms and peak current under varied stress voltage and device failure voltage.A new discharge model called the ＂sparkover-induced model＂ is proposed based on the results.Then,failure mechanism analysis and model simulation are performed to prove that the transient peak current caused by a sparkover of low arc impedance will result in the devices＇ premature damage when the potential difference between the no-connect metal cover and the chip exceeds the threshold voltage of sparkover.
