M. Savage, K. Struve, K. Austin, S. Coffey, P.A. Jones, N. Joseph, D. Kirschner, J. Lott, B. Oliver, R. Spielman
{"title":"Considerations for improvements to the 25 TW Saturn high-current driver","authors":"M. Savage, K. Struve, K. Austin, S. Coffey, P.A. Jones, N. Joseph, D. Kirschner, J. Lott, B. Oliver, R. Spielman","doi":"10.1109/PPPS34859.2019.9009671","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009671","url":null,"abstract":"The Saturn X-ray generator is a 2.5 megavolt, 10 megampere electrical driver at Sandia National Laboratories. Saturn has been in operation for more than 30 years. Work is underway to identify key areas of the machine, improvement of which would benefit operational efficiency and reproducibility of the system. Saturn is used to create high-dose, short-pulse intense ionizing radiation environments for testing electronic and mechanical systems. Saturn has 36 identical modules driving a common electron beam bremsstrahlung load. Each module utilizes a microsecond Marx generator, a megavolt gas switch, and untriggered water switches in a largely conventional pulse-forming system. Achieving predictable and reliable radiation exposure is critical for users of the facility. Saturn has endured decades of continual use with minimal opportunities for research, improvements, or significant preventive maintenance. Because of degradation in components and limited attention to electrical performance, the facility has declined both in the number of useful tests per year and their repeatability. The Saturn system resides in a cylindrical tank 33m in diameter, and stores 5.6 MJ at the nominal operating Marx charge voltage. The system today is essentially identical to that described by Bloomquist in 1987. [1] Advances in technology for large pulsed power systems affords opportunities to improve the performance and more efficiently utilize the energy stored. Increased efficiency can improve reliability and reduce maintenance. The goals for the Saturn improvement work are increased shot rate, reduced X-ray dose shot-to-shot dose fluctuation, and reduced required maintenance. Major redesign with alternate pulsed power technology is considered outside the scope of this effort. More X-ray dose, larger exposure area, and lower X-ray endpoint energy are also important considerations but also deemed outside the scope of the present project due to schedule and resource constraints. The first considerations, described here, are improving the present design with better components.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"1 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":"130321470","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}
{"title":"A Study on Attenuation Characteristics of Explosive Emission Cathode Plasma Based on Ultra-High Speed Camera Technology","authors":"Tengfang Wang, Shuming Peng","doi":"10.1109/PPPS34859.2019.9009710","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009710","url":null,"abstract":"Explode emission cathodes can be used to generate intense-current relativistic electron beams(IREBs) required for high-power microwave(HPM) systems, its characteristics affect the performance of HPM system. This type of cathode forms a plasma on the surface of the cathode during the emission process, and the electron beam is mainly obtained from the plasma. Therefore, the characteristics of the plasma are directly related to the beam characteristics, including the uniformity of plasma generation, the rate of expansion and attenuation. The attenuation characteristics are related to the repetitive performance of the cathode. In this paper, a ultra-high speed framing camera is used to construct a diagnostic system to take pictures of cathode plasma luminescence. The camera has 12 channels and can perform up to 24 frames. By setting the exposure time and delay timing of different channels, high-speed photography can be performed over a long time to obtain state information of cathode plasma at different time points during the attenuation process after the explosion emission, the result is very intuitive. The intense-current emission experiment was carried out by using a ring-shaped stainless steel cathode. The camera photographed the plasma luminescence on the front the cathode. The image processing and analysis showed that the attenuation time of the explosion emission cathode plasma was about 42µs, and the plasma gradually expanded from the cathode surface to the anode during the attenuation process. The expansion rate is on the order of cm/µs and is affected by the guiding magnetic field, and the distribution is very uneven. This result has important reference significance for studying the characteristics of explode emission cathode plasma.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"51 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":"127601215","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}
Maliang Wan, Wenzhong Zhou, Zhencheng Mu, Li Jian, Xu Xi’nan, Meifei Liu, Wang Bo, Linyan Rong, Zhexin Xie
{"title":"Design of High-Voltage Pulse Generator Control System for CSNS Linac RF System","authors":"Maliang Wan, Wenzhong Zhou, Zhencheng Mu, Li Jian, Xu Xi’nan, Meifei Liu, Wang Bo, Linyan Rong, Zhexin Xie","doi":"10.1109/PPPS34859.2019.9009742","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009742","url":null,"abstract":"China Spallation Neutron Source (CSNS) is the first neutron source facility in developing countries. it includes a powerful linear proton accelerator, a rapid circling synchrotron, a target station and three neutron instruments[1]. As one of the largest science and technology infrastructure projects in China, CSNS is expected to have positive effects in promoting the sciences, high-tech development and national security. Klystron power supply of CSNS is an important part of linac. High-voltage pulse generator is used for the mod_anode of Klystron. High-voltage pulse generator is composed of 400Hz series-resonant DC high-voltage power supply and solid state modulator. it includes variable frequency power supply (50Hz converted to 400Hz), step-up transformer (0.5kV-6kV), 400Hz series-resonant L/C, energy storage capacitor bank and high-voltage pulse modulator. This paper introduces the structure and principle of the high-voltage pulse generator, Focusing on the introduction of high-voltage pulse generator control system, test and operation of high-voltage pulse generator.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"36 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":"127737560","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}
{"title":"High Sensitivity HEH Monitor","authors":"V. Senaj, D. Pastor, T. Kramer","doi":"10.1109/PPPS34859.2019.9009620","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009620","url":null,"abstract":"The most critical failure mode of HV semiconductors exposed to radiation is Single Event Burnout (SEB). The probability of this catastrophic failure mode is strongly dependent on the applied bias voltage and is triggered by either heavy ions or High Energy Hadrons (HEH). The Large Hadron Collider (LHC) Beam Dumping System (LBDS) comprises 50 pulse generators operating at up to 28 kV and contains 800 HV GTOs and 480 HV IGBTs for the triggering system. All generators are installed underground in the galleries parallel to and shielded from the LHC tunnel but some HEH leak from the tunnel into the galleries via interconnecting cable ducts. Failure of a HV semiconductor due to SEB can lead to system malfunction and potential deterioration of downstream equipment. Shielding of the cable ducts has been done in the past, HEH flux is most likely well under 106 HEH/cm2/year, and therefore below the sensitivity of presently used neutron SRAM SEU monitors, showing zero counts until now. Future operation with increased beam energy will result in increased voltage applied to the GTOs and consequently higher SEB probability. In order to improve the accuracy of the failure rate estimation necessary for preparing mitigation measures, more sensitive HEH flux measurements are necessary.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"46 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":"125693214","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}
Yilin Wang, Jianhao Ma, Weirong Zeng, Shoulong Dong, Liang Yu, C. Yao
{"title":"The Development of All Solid-state Multi-turn Linear Transformer Driver","authors":"Yilin Wang, Jianhao Ma, Weirong Zeng, Shoulong Dong, Liang Yu, C. Yao","doi":"10.1109/PPPS34859.2019.9009675","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009675","url":null,"abstract":"An all solid-state multi-turn linear transformer driver is designed for the application of pulse power techniques with high-voltage, large-current and wide pulse width in pulsed electromagnetic biomedical applications. The magnetic core of the LTD pulse generator adopts the method of multi-turn winding, which can output pulse of wide pulse width. The isolation of drive power supply and energy charging with co-direction winding of LTD modules is designed, and the isolation voltage of magnetic cores is the working voltage of LTD modules. The multi-turn LTD pulse generator is composed of 10 LTD modules. Each module is connected in parallel by 18 energy storage capacitors and MOSFETs discharge switches, and its synchronous drive circuit is designed. Through the analysis and selection of the components model and circuit, a modular all-solid-state pulse generator based on multi-turn LTD is development, which can output pulse parameters for the voltage amplitude 0–5 kV, the output pulse current up to 500 A, pulse width 200 ns-5 µs, pulse rise time 30 ns, falling time 16 ns, and its parameters can adjusted flexibly such as pulse width and amplitude.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"37 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":"130059755","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}
A. Young, R. Speer, A. Ferriera, G. Mease, A. Pearson, A. Ray
{"title":"On the Performance of Triggered Closing Switches Deployed in High Explosive Pulsed Power Experiments","authors":"A. Young, R. Speer, A. Ferriera, G. Mease, A. Pearson, A. Ray","doi":"10.1109/PPPS34859.2019.9009992","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009992","url":null,"abstract":"Reported in this paper are the results of efforts to improve the performance of a triggered closing switch system used in a 450 kilojoule capacitor bank, which is used as a seed current source for magnetic flux compression generator experiments. The capacitor bank switch utilizes two different high power closing switches: a commercial-off-the-shelf pressurized spark gap and a custom designed solid dielectric puncture switch. Discussion of the spark gap will focus on the results of an investigation aimed at determining the pre-fire rates, self-break voltage distributions, function times and jitter characteristics of two different switches. A campaign aimed at improving the function time and jitter of a Mylar® solid dielectric puncture switch resulted in almost a two-fold decrease in switching characteristics after reducing the thickness of the solid dielectric.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"107 2 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":"130469023","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}
{"title":"Study on aging characteristics of DC transmission line arrester considering impact load","authors":"Li Mengzhen, Guo Jie, Le Bo, Gao Zihao, Wu Yuying","doi":"10.1109/PPPS34859.2019.9009849","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009849","url":null,"abstract":"Metal oxide arrester (MOA) is the main equipment to limit overvoltage in power system. It has been widely used in UHVDC project in China. The UHVDC system has longer deliver distance. Under the influence of various external factors, the state characteristic parameters of MOA will change and its performance will decline, which is called the aging problem. Unlike the arrester in AC system whose continuous operating voltage is power frequency voltage, the aging of MOA resistors in DC system is more complicated. Based on a ±1100kV UHVDC system in China, this paper studies voltage load waveforms of transmission line arrester in UHVDC system under different operating conditions, and analyzes its amplitude by mathematical methods. Based on simulation, the impedance characteristics and power consumption characteristics of DC line MOA proportional components under multi-factors were studied. Considering the influence of impact load, the long-term integrated DC aging characteristics of MOA were studied. The comprehensive aging test results show that during the aging test, the DC reference voltage of the mainstream formula has an increasing trend, which increases by a maximum of 6.05%; the DC leakage current shows a decreasing trend with a maximum reduction of 76%; the power loss shows a decreasing trend with a maximum of 71.4%. The AC reference voltage shows an increasing trend. The full current, resistive fundamental wave, and third harmonic show a decreasing trend. The capacitance and tanδ decrease slightly, and the residual voltage does not change significantly. The influence of different impact loads on DC aging of MOV from the most to the least is: square wave>lightning wave>high current.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"99 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":"132999943","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}
{"title":"Pulse Power System","authors":"P. Stone, Aka P.V. Vassioukevitch","doi":"10.1109/PPPS34859.2019.9009982","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009982","url":null,"abstract":"This article is a continuation of the research of Pulse Power Systems [1], [2]. Current features as well as complications of Electromagnetic Launchers (EL) of projectile are well known. The low efficiency of EL prompted the research for a fundamentally new type of devices, as well as a new type of electromagnetic energy sources. This article is considering a new type of EL combined with modified Bitter Magnet and High-Frequency Pulse energy generator as a power source for sections of EL. Devices are protected by international applications for inventions. The absence of galvanic contact between the accelerated projectile and the EL barrel resolving the issue of friction and overheating. Also Sectional design of the EL resolving the issue of useless accumulation of electromagnetic energy in the barrel. Using modified Bitter Magnet in EL sections allows to create magnetic fields tens of times higher density than in a well known EL, which increases the electromagnetic pressure by hundreds of times to accelerate the projectile. This article illustrates EL in greater details along with a test result of the EL prototype.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"21 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":"132336993","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}
Kiyotaka Okada, Kazuki Oishi, S. Kodama, Douyan Wang, T. Namihira
{"title":"Quantification of OH radicals generated by nanosecond pulsed discharge plasma","authors":"Kiyotaka Okada, Kazuki Oishi, S. Kodama, Douyan Wang, T. Namihira","doi":"10.1109/PPPS34859.2019.9009980","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009980","url":null,"abstract":"In conventional water treatment, wastewater is purified by a biological method. However, this method has some problems, such as dissipation of time, high cost for treatment, necessity of large facilities, and existence of some pollutants that are not easily to be decomposed. Therefore, the development of advanced water treatment technologies that can solve those problems is required. In recent years, discharge plasmas have been used as effective method for purifying environmentally polluted water. Some researchers reported that the species which have high oxidation potential, such as OH radical, O radical, O3 and etc., are produced by pulsed discharge plasmas generated in water surface. Among them, OH radicals have the highest oxidizing power. In this work, OH radicals generated by the nanosecond pulsed discharge was evaluated using a chemical prove method. In this method, terephthalic acid (TA) was used as an OH radical scavenger and the given fluorescence of the resulted 2-hydroxyterephthalic acid (HTA) was measured. However, it can be estimated that the HTA in the reaction process could be decomposed by discharge afterwards. Furthermore, there is no report of OH radical measurement based on the amount of HTA decomposition. This means, the accuracy of OH radical evaluation needs room to improve. Therefore, we measured the amount of HTA decomposition by nanosecond pulsed discharge, and successfully examined the decomposition amount of HTA. As the result, the generated OH radicals with consideration of HTA decomposition is successfully evaluated.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"57 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":"132683237","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}
T. Boutraa, Sahar A. Fadhlalmawla, Jamal Q. M. Almarashi, A. Mohamed
{"title":"Argon Cold Atmospheric Pressure Plasma Jet Enhancing Seed Germination of Fenugreek (Trigonella Foenum-Graecum)","authors":"T. Boutraa, Sahar A. Fadhlalmawla, Jamal Q. M. Almarashi, A. Mohamed","doi":"10.1109/PPPS34859.2019.9009694","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009694","url":null,"abstract":"Atmospheric pressure cold plasma jet gained a great interest overall the world due to its wide band of application in medicine, industry and agriculture. Therefore, in this work we investigated the impact of cold atmospheric pressure argon plasma jet on the germination of fenugreek (Trigonella foenum-graecum L.). The current-voltage sinusoidal waveforms show that two current pulses per each half a cycle of applied voltage was used in this experiment. The generated plasm jet emission spectrum show the presence of O and OH radicals. The gas temperature of the plasma jet was found to be 310 k at 2mm below the jet nozzle. The plasma jet system is a two-electrode system used with two exposure times; 1-min and 15-min, with and without accelerated grounded electrode (AGE) to investigate the effect of cold plasma on seeds germination. The results showed that plasma jet had a significant effect on seed germination at both exposure times. The effect of the three parameters; O-radicals, enhancement of the electric field and streamers, might be the cause of seed germination improvement by the plasma jet. The findings of this study suggested that cold plasma could stimulate the germination, taking in consideration that cold plasma is an economic and pollution-free method in plant productivity improvement.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"72 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":"115643000","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}