Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009924
T. Sasaki, R. Mabe, Kazumasa Takahashi, T. Kikuchi
We have demonstrated a thin liquid-metal load for repeatable applications using pulsed-power discharge. To understand the liquid-metal behavior, we measured the liquid-metal diameter as a function of hydrodynamical normalized number. We found that the length and diameter of liquid-metal can use the hybrid X-pinch system. To demonstrate the thin liquid-metal load, we used a pulsed-power system using a magnetic switch. We demonstrated the repeatable discharge using pulsed-power system. The results show that the time-evolution of optical emission is reproduced within the experiments. It reveals that our proposed liquid-metal load is well repeatable applications for pulsed-power discharge.
{"title":"Fine Liquid-Metal Load for Repeatable Applications of Pulsed-power Discharge","authors":"T. Sasaki, R. Mabe, Kazumasa Takahashi, T. Kikuchi","doi":"10.1109/PPPS34859.2019.9009924","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009924","url":null,"abstract":"We have demonstrated a thin liquid-metal load for repeatable applications using pulsed-power discharge. To understand the liquid-metal behavior, we measured the liquid-metal diameter as a function of hydrodynamical normalized number. We found that the length and diameter of liquid-metal can use the hybrid X-pinch system. To demonstrate the thin liquid-metal load, we used a pulsed-power system using a magnetic switch. We demonstrated the repeatable discharge using pulsed-power system. The results show that the time-evolution of optical emission is reproduced within the experiments. It reveals that our proposed liquid-metal load is well repeatable applications for pulsed-power discharge.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115956647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009890
M. Sato, H. Takaura, T. Sakugawa, H. Hosano
This paper reports on the characteristics of shock waves generated by discharges with different electrode diameters. In the study, underwater discharges were generated by using a magnetic pulse compression (MPC) circuit. We used a pin-to-pin electrode to discharge between the electrodes and generate a shock wave. The electrode diameters used in the experiments were 0.8 mm, 1.2 mm and 1.5 mm and the gap distance were fixed at 0.2 mm. The shock waves were studied by pressure measurement through an elastic membrane using a fiber optic probe hydrophone (FOPH) pressure transducer. We describe the relationship between the peak voltage, the peak current and the discharge energy and the peak pressure of the shock waves. The discharge waveforms were changed under different experimental conditions. It was found that the maximum pressure of the shock wave became stronger as the current density increased. Also, we calculated the shock wave energy density from the obtained shock wave waveforms. As a result of examining the relationship between the maximum pressure and the shockwave energy density, it was found that the shock waves generated by the discharges with different electrode diameters had different shock wave energy density at the same peak pressures of the shock waves.
{"title":"Investigation on shock wave generated by underwater discharge due to different progress of plasma","authors":"M. Sato, H. Takaura, T. Sakugawa, H. Hosano","doi":"10.1109/PPPS34859.2019.9009890","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009890","url":null,"abstract":"This paper reports on the characteristics of shock waves generated by discharges with different electrode diameters. In the study, underwater discharges were generated by using a magnetic pulse compression (MPC) circuit. We used a pin-to-pin electrode to discharge between the electrodes and generate a shock wave. The electrode diameters used in the experiments were 0.8 mm, 1.2 mm and 1.5 mm and the gap distance were fixed at 0.2 mm. The shock waves were studied by pressure measurement through an elastic membrane using a fiber optic probe hydrophone (FOPH) pressure transducer. We describe the relationship between the peak voltage, the peak current and the discharge energy and the peak pressure of the shock waves. The discharge waveforms were changed under different experimental conditions. It was found that the maximum pressure of the shock wave became stronger as the current density increased. Also, we calculated the shock wave energy density from the obtained shock wave waveforms. As a result of examining the relationship between the maximum pressure and the shockwave energy density, it was found that the shock waves generated by the discharges with different electrode diameters had different shock wave energy density at the same peak pressures of the shock waves.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"155 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114734203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009978
Ruiyang Guan, Z. Jia
Arc accidents may cause serious problems in power grid. Yet, the progress of arc evolution is very complicated and rapidly changed, which can be easily disturbed by external factors. Here, in order to better describe DC arc mechanism and exclude external influence factors, a testing platform, which can produce a small DC arc in the condition of gap length less than 15 mm and current less than 60 mA, was built. Arc evolution and macroscopic forms were captured by a high-speed camera. Spectrums of various states of arc were measured by a multichannel spectrometer and the arc temperatures were calculated based on the spectral lines. The relationships between DC arc resistance and gap length and current were studied. The experimental results show that DC arc develops from the positive electrode rather than negative electrode. With the current increasing, the macroscopic forms of arc evolution progress are mainly consisted of 4 periods: spark, purple-arc, yellow-arc and flame-arc. The arc spectrogram reflects that the wavelengths of 4 maximum relative intensities are 315.86 nm, 337.107 nm, 357.65 nm and 391.42 nm, respectively. The relationship between arc resistance and current is a power function, while it is a linear function of gap length. The work in this paper is helpful to understand the progress of DC arc evolution.
{"title":"Researches on Spectrums and Macroscopic Forms of DC Arc in a Short Air Gap","authors":"Ruiyang Guan, Z. Jia","doi":"10.1109/PPPS34859.2019.9009978","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009978","url":null,"abstract":"Arc accidents may cause serious problems in power grid. Yet, the progress of arc evolution is very complicated and rapidly changed, which can be easily disturbed by external factors. Here, in order to better describe DC arc mechanism and exclude external influence factors, a testing platform, which can produce a small DC arc in the condition of gap length less than 15 mm and current less than 60 mA, was built. Arc evolution and macroscopic forms were captured by a high-speed camera. Spectrums of various states of arc were measured by a multichannel spectrometer and the arc temperatures were calculated based on the spectral lines. The relationships between DC arc resistance and gap length and current were studied. The experimental results show that DC arc develops from the positive electrode rather than negative electrode. With the current increasing, the macroscopic forms of arc evolution progress are mainly consisted of 4 periods: spark, purple-arc, yellow-arc and flame-arc. The arc spectrogram reflects that the wavelengths of 4 maximum relative intensities are 315.86 nm, 337.107 nm, 357.65 nm and 391.42 nm, respectively. The relationship between arc resistance and current is a power function, while it is a linear function of gap length. The work in this paper is helpful to understand the progress of DC arc evolution.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125431916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009621
David Alderman, Christopher Tremble, Shutong Song, C. Jiang, J. Sanders, D. Singleton
Combustion efficiency and rate of ignition were shown to be improved when fuel-air ignition was initiated with highly non-equilibrium plasmas generated by highvoltage, nanosecond pulses, also known as transient plasma ignition (TPI). In order to optimize the pulse power parameters for plasma ignition for combustion, detailed experimental investigations of the effect of risetime and pulse repetition frequency (PRF) were conducted for atmospheric pressure static methane/air ignitions. Plasmas driven by 10 ns, 12 kV pulses at a range of PRF from 1 kHz to 10kHz were generated for combustion ignition with a conventional spark plug electrode configuration. Experiments revealed that a different mode in the plasma was initiated when the fuel/air mixture was ignited. At constant pulse duration and PRF, this plasma occurred earlier for the faster rise time (e.g. 4 ns) compared to the longer one (e.g. 8 ns) [1]. In addition, faster PRF favored the earlier plasma mode change or earlier ignition. Importantly, the kinetics of reactive plasma species that were generated during the TPI and combustion were investigated using optical emission spectroscopy (OES). Filtered high speed imaging in combination with electrical measurements are to help understand the plasma rotational temperature related to combustion that is initiated with different pulse rise times and PRFs at a constant pulse width of 10 ns. Gas temperature of the repetitively pulsed plasma ignition for combustion is discussed by measuring the rotational temperature of the second positive systems of nitrogen N2 (C-B).
{"title":"Plasma kinetics study of a repetitive 10-NS pulsed plasma ignition for combustion","authors":"David Alderman, Christopher Tremble, Shutong Song, C. Jiang, J. Sanders, D. Singleton","doi":"10.1109/PPPS34859.2019.9009621","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009621","url":null,"abstract":"Combustion efficiency and rate of ignition were shown to be improved when fuel-air ignition was initiated with highly non-equilibrium plasmas generated by highvoltage, nanosecond pulses, also known as transient plasma ignition (TPI). In order to optimize the pulse power parameters for plasma ignition for combustion, detailed experimental investigations of the effect of risetime and pulse repetition frequency (PRF) were conducted for atmospheric pressure static methane/air ignitions. Plasmas driven by 10 ns, 12 kV pulses at a range of PRF from 1 kHz to 10kHz were generated for combustion ignition with a conventional spark plug electrode configuration. Experiments revealed that a different mode in the plasma was initiated when the fuel/air mixture was ignited. At constant pulse duration and PRF, this plasma occurred earlier for the faster rise time (e.g. 4 ns) compared to the longer one (e.g. 8 ns) [1]. In addition, faster PRF favored the earlier plasma mode change or earlier ignition. Importantly, the kinetics of reactive plasma species that were generated during the TPI and combustion were investigated using optical emission spectroscopy (OES). Filtered high speed imaging in combination with electrical measurements are to help understand the plasma rotational temperature related to combustion that is initiated with different pulse rise times and PRFs at a constant pulse width of 10 ns. Gas temperature of the repetitively pulsed plasma ignition for combustion is discussed by measuring the rotational temperature of the second positive systems of nitrogen N2 (C-B).","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126602417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009828
D. Pastor, V. Senaj, T. Kramer
Reliable operation of the Large Hadron Collider Beam Dumping System (LBDS) is crucial for machine safety. The LBDS is composed of pulse generators, containing HV semiconductors, which are susceptible to Single Event Burnout (SEB) - a catastrophic phenomenon for HV semiconductors - due to High Energy Hadrons (HEH). In order to better assess the HEH flux and impact, development of an HEH monitor, based on the SEB phenomenon in HV Si diodes, is ongoing. This will improve the accuracy of SEB related failure rate estimation and will help to guide mitigation measures. A low cost acquisition system for the HEH monitor has been developed. The acquisition system is based on a microcontroller Arduino Yun, which is in charge of counting the SEBs, sending the data to a MySQL® Database and store them in an internal USB or SD card as a backup. In addition, periodic ‘alive’ signals and remote control of sensitivity have been developed. The whole system has already experienced several irradiation campaigns without any malfunction.
{"title":"Data Acquisition System for HEH Monitor","authors":"D. Pastor, V. Senaj, T. Kramer","doi":"10.1109/PPPS34859.2019.9009828","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009828","url":null,"abstract":"Reliable operation of the Large Hadron Collider Beam Dumping System (LBDS) is crucial for machine safety. The LBDS is composed of pulse generators, containing HV semiconductors, which are susceptible to Single Event Burnout (SEB) - a catastrophic phenomenon for HV semiconductors - due to High Energy Hadrons (HEH). In order to better assess the HEH flux and impact, development of an HEH monitor, based on the SEB phenomenon in HV Si diodes, is ongoing. This will improve the accuracy of SEB related failure rate estimation and will help to guide mitigation measures. A low cost acquisition system for the HEH monitor has been developed. The acquisition system is based on a microcontroller Arduino Yun, which is in charge of counting the SEBs, sending the data to a MySQL® Database and store them in an internal USB or SD card as a backup. In addition, periodic ‘alive’ signals and remote control of sensitivity have been developed. The whole system has already experienced several irradiation campaigns without any malfunction.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"680 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115119478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009935
T. Hayashi, Souhei Toyoda, Tomokazu Kanna, T. Sakugawa
There are many reports reporting chemically active species using underwater discharge plasma. Another method is to bubble in water to produce chemically active species. However, it is difficult to measure the active species by spectroscopy in the discharge in water. We generated chemically active species utilizing streamer discharge generated on the water surface and measured spectroscopic measurements. A magnetic pulse compression circuit was used to generate streamer discharge. For spectroscopic measurement, a high sensitive spectroscopy capable of time resolved spectroscopy was used. Discharge on the water surface randomly propagations, so it is difficult to perform spectroscopic measurement at a fixed point. Therefore, we could develop a discharge chamber that can control the direction of progress of the streamer in one direction, and we were able to perform stable spectroscopic measurements. Particularly chemically active species are OH, $mathrm{H}alpha, mathrm{H}beta$. The generation characteristics of these chemically active species were examined when the ground electrode was installed in the medium chamber and when it was installed outside the chamber. As a result, strong emission of OH radicals are observed at the high-speed rise of the pulse voltage.
{"title":"Spectroscopic Measurement of Active Species Generated in Streamer Discharge on Water Surface","authors":"T. Hayashi, Souhei Toyoda, Tomokazu Kanna, T. Sakugawa","doi":"10.1109/PPPS34859.2019.9009935","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009935","url":null,"abstract":"There are many reports reporting chemically active species using underwater discharge plasma. Another method is to bubble in water to produce chemically active species. However, it is difficult to measure the active species by spectroscopy in the discharge in water. We generated chemically active species utilizing streamer discharge generated on the water surface and measured spectroscopic measurements. A magnetic pulse compression circuit was used to generate streamer discharge. For spectroscopic measurement, a high sensitive spectroscopy capable of time resolved spectroscopy was used. Discharge on the water surface randomly propagations, so it is difficult to perform spectroscopic measurement at a fixed point. Therefore, we could develop a discharge chamber that can control the direction of progress of the streamer in one direction, and we were able to perform stable spectroscopic measurements. Particularly chemically active species are OH, $mathrm{H}alpha, mathrm{H}beta$. The generation characteristics of these chemically active species were examined when the ground electrode was installed in the medium chamber and when it was installed outside the chamber. As a result, strong emission of OH radicals are observed at the high-speed rise of the pulse voltage.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123487896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009876
K. Nagao, K. Sakurai, W. Takatsu, P. V. Thuần, T. Sugai, W. Jiang
The virtual cathode oscillator (vircator) is one of the promising devices oscillating high-power microwaves. Simplicity and high-power capability are advantages. However, the low efficiency and frequency stability are serious problems. To improve oscillation efficiency, strengthen the feedback of the electromagnetic wave to the electron beam by pre-modulating the injected electron beam. Using double-anode and configuring a cavity is effective. In this paper, we dealt a double-anode to improve output power. Experiments were carried out on a repetitively pulsed power generator “ETIGO-IV” (maximum output: 400 kV, 13 kA, 120 ns, 1 Hz). The output microwaves are diagnosed for peak power and energy by using horn antennas. The microwave frequency is obtained by fast-Fourier analysis of the signal recorded by a high-speed digital oscilloscope. From the experimental result, the microwaves are obtained peak power of ~100MW. These results are shown that the output of the virtual cathode oscillator can be progress by using the double-anode. In addition, particle-in-cell simulations were carried out by using a simulation code “MAGIC.” Simulation results are compared with experimental results to examine the effect of the double-anode and possible ways of further improvement of microwave efficiency.
虚阴极振荡器(vircator)是一种很有前途的大功率微波振荡器件。简单和高性能是优点。然而，效率低和频率不稳定是严重的问题。为了提高振荡效率，通过对注入的电子束进行预调制，加强电磁波对电子束的反馈。采用双阳极和配置空腔是有效的。在本文中，我们讨论了双阳极来提高输出功率。实验在重复脉冲发电机“ETIGO-IV”上进行(最大输出:400 kV, 13 kA, 120 ns, 1 Hz)。利用喇叭天线对输出微波进行峰值功率和能量诊断。通过对高速数字示波器记录的信号进行快速傅立叶分析，得到微波频率。实验结果表明，微波峰值功率为~100MW。结果表明，采用双阳极可以提高虚阴极振荡器的输出效率。此外，使用模拟代码“MAGIC”进行了细胞内粒子的模拟。将模拟结果与实验结果进行了比较，探讨了双阳极的效果以及进一步提高微波效率的可能途径。
{"title":"High-Power Microwave Generation by Double-Anode Virtual Cathode Oscillator","authors":"K. Nagao, K. Sakurai, W. Takatsu, P. V. Thuần, T. Sugai, W. Jiang","doi":"10.1109/PPPS34859.2019.9009876","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009876","url":null,"abstract":"The virtual cathode oscillator (vircator) is one of the promising devices oscillating high-power microwaves. Simplicity and high-power capability are advantages. However, the low efficiency and frequency stability are serious problems. To improve oscillation efficiency, strengthen the feedback of the electromagnetic wave to the electron beam by pre-modulating the injected electron beam. Using double-anode and configuring a cavity is effective. In this paper, we dealt a double-anode to improve output power. Experiments were carried out on a repetitively pulsed power generator “ETIGO-IV” (maximum output: 400 kV, 13 kA, 120 ns, 1 Hz). The output microwaves are diagnosed for peak power and energy by using horn antennas. The microwave frequency is obtained by fast-Fourier analysis of the signal recorded by a high-speed digital oscilloscope. From the experimental result, the microwaves are obtained peak power of ~100MW. These results are shown that the output of the virtual cathode oscillator can be progress by using the double-anode. In addition, particle-in-cell simulations were carried out by using a simulation code “MAGIC.” Simulation results are compared with experimental results to examine the effect of the double-anode and possible ways of further improvement of microwave efficiency.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121688667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009981
Zhang Lisong, Y. Mingtian, P. Lei, Z. Qiaogen
The paper is devoted to the calculation of equilibrium compositions, thermodynamic properties (mass density, enthalpy and specific heat at constant pressure) and transport coefficients (electrical conductivity, viscosity and thermal conductivity) of C4F7N/CO2 thermal plasma. Assuming local thermodynamic equilibrium, the species composition is determined using the principle of minimization of the Gibbs free energy. The transport properties are calculated by the Chapman-Enskog method. Some recently updated cross-sections or interaction potentials in the literature is adopted to obtain collision integrals. These data are computed in the temperature range between 300 K-30 kK, for a pressure between 0.1 MPa and 1 MPa and for several CO2 proportions. Transport coefficients of pure CO2 plasma are also compared with previously published values. The results clarify some basic chemical process in C4F7N/CO2 mixtures and provide reliable reference data for the arc simulations.
{"title":"Thermodynamic properties and transport coefficients of C4F7N/CO2 thermal plasma as an alternative to SF6","authors":"Zhang Lisong, Y. Mingtian, P. Lei, Z. Qiaogen","doi":"10.1109/PPPS34859.2019.9009981","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009981","url":null,"abstract":"The paper is devoted to the calculation of equilibrium compositions, thermodynamic properties (mass density, enthalpy and specific heat at constant pressure) and transport coefficients (electrical conductivity, viscosity and thermal conductivity) of C4F7N/CO2 thermal plasma. Assuming local thermodynamic equilibrium, the species composition is determined using the principle of minimization of the Gibbs free energy. The transport properties are calculated by the Chapman-Enskog method. Some recently updated cross-sections or interaction potentials in the literature is adopted to obtain collision integrals. These data are computed in the temperature range between 300 K-30 kK, for a pressure between 0.1 MPa and 1 MPa and for several CO2 proportions. Transport coefficients of pure CO2 plasma are also compared with previously published values. The results clarify some basic chemical process in C4F7N/CO2 mixtures and provide reliable reference data for the arc simulations.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122754966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009859
Xu Lin, Zhang Jun, Dong Jiannian, Wan Hao, S. Hao
This paper has designed a 200-KJ pulsed power system (PPS) for Electrothermal-Chemical Launch (ETCL). The PPS consists of pulsed power module, high voltage charger, remote control system and high power connector. Two independent 100-KJ pulse forming units (PFUs) are integrated in one pulse power module and are charged to the same voltage by one HV charger. In each PFU, a pulse capacitor, a semiconductor switch stack, an inductor, a dump system and a data acquisition system were integrated. The PFU was designed to achieve a peak current up to 50KA at a maximum charging voltage of 10KV. The high voltage charger was integrated into the pulse power module. The experimental data of PPS showed that output current meets the requirement.
{"title":"Design of a Vehicular 200-Kj Pulsed Power System for Electrothermal-Chemical Launch Experiment","authors":"Xu Lin, Zhang Jun, Dong Jiannian, Wan Hao, S. Hao","doi":"10.1109/PPPS34859.2019.9009859","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009859","url":null,"abstract":"This paper has designed a 200-KJ pulsed power system (PPS) for Electrothermal-Chemical Launch (ETCL). The PPS consists of pulsed power module, high voltage charger, remote control system and high power connector. Two independent 100-KJ pulse forming units (PFUs) are integrated in one pulse power module and are charged to the same voltage by one HV charger. In each PFU, a pulse capacitor, a semiconductor switch stack, an inductor, a dump system and a data acquisition system were integrated. The PFU was designed to achieve a peak current up to 50KA at a maximum charging voltage of 10KV. The high voltage charger was integrated into the pulse power module. The experimental data of PPS showed that output current meets the requirement.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131677935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-01DOI: 10.1109/PPPS34859.2019.9009950
C. J. Buchenauer, J. Pouncey, J. Lehr
Efficient pulse charging of small high-voltage capacitive loads with Marx generators is limited by the parasitic capacitance of the Marx network. Yet stray capacitance to ground can not be much smaller than the inter-stage capacitance for proper Marx erection. In earlier work, Marx network designs were found that transferred energy with perfect efficiency [1][2]. Ideal network designs were determined by constraints imposed by energy and charge conservation, and by waveform and resonant frequency symmetries. Lossless linear networks that transform Energy between states of purely magnetic and/or purely electrostatically stored energy must exhibit waveforms that are periodic in time [3][4]. The final step involves the assignment of the network resonant frequencies to the fundamental and only even harmonics of the fundamental. Simultaneous switch closure is also required. For regular network solutions, only the lower-order harmonics possess appreciable energy, and suitable approximate solutions may be found by ignoring the higher-order resonant modes and allowing stray capacitances to possess common optimal values. Sequential Marx-switch triggering produces a mixed initial state that compromises the viable solutions. The few percent of energy remaining induces high frequency oscillations in the circuit that could lead to early component failure. Correction attempts have had limited success except for mid-stage Marx triggering, which shows significant benefits. Simultaneous laser triggering is a promising ultimate solution to this problem [5].
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