A trigger device and a triggered pseudospark switch （TPSS） were designed based on surface flashover technology, in order to meet the requirements from present pulse power technology and pulse current test technology...A trigger device and a triggered pseudospark switch （TPSS） were designed based on surface flashover technology, in order to meet the requirements from present pulse power technology and pulse current test technology such as a long lifetime, reliability in a wide voltage range, a short delay time, as well as small delay jitters. The trigger devices were made from different dielectric materials, with their permittivities from tens to thousands. The trigger characteristics of TPSS were investigated. The results indicate that the high-dielectric trigger device shows better performance and higher emitted charge of the electron emission within all adjusted parameters including the gas pressure and applied voltage. For the dielectric material with relative permittivity εr of 3460, when the gas pressure is 7 Pa, the hold-off voltage of TPSS is 28 kV, the minimum trigger switch voltage drops to 128 V, the minimum discharging delay time and delay jitter are less than 35ns and 6ns, respectively, and the reliable operation can be reached within a very large range of charging voltage, between 0.46% and 99% of its self-breakdown voltage.展开更多
Accurate and reliable triggering is one of the most important issues with high power pseudospark switch, because it not only has an impact on the design of discharge chamber of switch, but also has an influence on the...Accurate and reliable triggering is one of the most important issues with high power pseudospark switch, because it not only has an impact on the design of discharge chamber of switch, but also has an influence on the dynamic range of operation voltage, repetition frequencies and lifetime of switch. The unique feature of pseudospark switch is its hollow cathode geometry. The hollow cathode effect produced by the hollow cathode provides the protection of the switch for the triggering unit from erosion by high discharge plasma. In this paper, a zinc oxide (ZnO) surface flashover triggering is presented. This trigger unit possesses an excellent time delay (80 ns - 360 ns) and jitter (20 ns - 50 ns) at the switch voltage of 30 kV - 2 kV. The emitted plasma electron density is high enough to trigger switch reliably down to switch voltage of 440 V.展开更多
A crowbar impulse current circuit for testing the switch-type surge protective device （SPD） is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main dischar...A crowbar impulse current circuit for testing the switch-type surge protective device （SPD） is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main discharging switch, and a crowbar pseudospark switch. The active trigger technology was studied in the crowbar impulse current circuit. The circuit monitors the main discharging current and generates a trigger signal at a proper time for the crowbar pseudospark switch operation. The trigger characteristics of the main discharge switch and the crowbar pseu- dospark switch were investigated. By monitoring the preset applied capacitor voltage, the gap distance of the main discharging switch could be adjusted to ensure a discharging delay time less than 2 μs. Equipped with a surface ttashover trigger device made of high relative perimittivity dielectric material BaTiO3 （εr = 3460）, the discharge delay time of the crowbar pseudospark switch is less than 85 ns, and the minimum operating voltage is less than 1% of its self-breakdown voltage. With a storage capacitor of 9 μF , an inductor of 18 μH and a crowbar pseudospark switch, a load of 30 mΩ and an applied capacitor voltage of 40 kV, an impulse current waveform of maximum 25 kA was generated with a rise time and time to half peak value of 17.2 μs and 336μs respectively.展开更多
文摘A trigger device and a triggered pseudospark switch （TPSS） were designed based on surface flashover technology, in order to meet the requirements from present pulse power technology and pulse current test technology such as a long lifetime, reliability in a wide voltage range, a short delay time, as well as small delay jitters. The trigger devices were made from different dielectric materials, with their permittivities from tens to thousands. The trigger characteristics of TPSS were investigated. The results indicate that the high-dielectric trigger device shows better performance and higher emitted charge of the electron emission within all adjusted parameters including the gas pressure and applied voltage. For the dielectric material with relative permittivity εr of 3460, when the gas pressure is 7 Pa, the hold-off voltage of TPSS is 28 kV, the minimum trigger switch voltage drops to 128 V, the minimum discharging delay time and delay jitter are less than 35ns and 6ns, respectively, and the reliable operation can be reached within a very large range of charging voltage, between 0.46% and 99% of its self-breakdown voltage.
基金The project supported by the National Nature Science Foundation of China(No.10035020)
文摘Accurate and reliable triggering is one of the most important issues with high power pseudospark switch, because it not only has an impact on the design of discharge chamber of switch, but also has an influence on the dynamic range of operation voltage, repetition frequencies and lifetime of switch. The unique feature of pseudospark switch is its hollow cathode geometry. The hollow cathode effect produced by the hollow cathode provides the protection of the switch for the triggering unit from erosion by high discharge plasma. In this paper, a zinc oxide (ZnO) surface flashover triggering is presented. This trigger unit possesses an excellent time delay (80 ns - 360 ns) and jitter (20 ns - 50 ns) at the switch voltage of 30 kV - 2 kV. The emitted plasma electron density is high enough to trigger switch reliably down to switch voltage of 440 V.
文摘A crowbar impulse current circuit for testing the switch-type surge protective device （SPD） is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main discharging switch, and a crowbar pseudospark switch. The active trigger technology was studied in the crowbar impulse current circuit. The circuit monitors the main discharging current and generates a trigger signal at a proper time for the crowbar pseudospark switch operation. The trigger characteristics of the main discharge switch and the crowbar pseu- dospark switch were investigated. By monitoring the preset applied capacitor voltage, the gap distance of the main discharging switch could be adjusted to ensure a discharging delay time less than 2 μs. Equipped with a surface ttashover trigger device made of high relative perimittivity dielectric material BaTiO3 （εr = 3460）, the discharge delay time of the crowbar pseudospark switch is less than 85 ns, and the minimum operating voltage is less than 1% of its self-breakdown voltage. With a storage capacitor of 9 μF , an inductor of 18 μH and a crowbar pseudospark switch, a load of 30 mΩ and an applied capacitor voltage of 40 kV, an impulse current waveform of maximum 25 kA was generated with a rise time and time to half peak value of 17.2 μs and 336μs respectively.
