K. Eguchi, R. Fujita, D. Wang, K. Tomita, T. Namihira
{"title":"Laser Thomson Scattering Diagnostics for Streamer Discharge in HE Gas","authors":"K. Eguchi, R. Fujita, D. Wang, K. Tomita, T. Namihira","doi":"10.1109/PPPS34859.2019.9009628","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009628","url":null,"abstract":"Streamer discharge plasma, a type of non-thermal plasma, has received global attention as a source of reactive radicals, and is used for many applications such as ozone generation, decomposition of NOx and other gas pollutants, cleaning water, disinfection, deodorization, and medical applications. The tip of streamer discharge, known as the streamer head, in particular contributes to radical production. The peak electric field is located on the streamer head on the axis of symmetry of the discharge, likely resulting in many radical types. Very remarkable results in NO removal efficiency and superior ozone generation yield performed by streamer discharge have reported. Improving gas treatment methods requires understanding of physical characteristics of streamer discharge and streamer head, for example, electron temperature and electron density. This study investigates characteristics of streamer discharge by observing the propagation process of streamer head in a needle to conic electrode with positive voltage using a high speed gated emICCD camera. Then, incoherent laser Thomson scattering (LTS) diagnostic for streamer discharge and streamer head with positive voltage was performed. LTS diagnostic is considered to be the most reliable technique measuring electron temperature and density in plasma simultaneously. In addition, LTS diagnostic has high resolution temporally and spatially, therefore, LTS diagnostic can measure location dependence of electron temperature and density in streamer discharge including streamer head. The measurement point was 1 mm and 2 mm from tip of the high voltage needle electrode, and Thomson scattering signals were measured at the point of initial phase of streamer head propagation. In the results, electron temperature of streamer discharge was 4 to 6 eV, electron density of streamer discharge was 1021 m−3 order. This study has proven that LTS diagnostic can measure electron temperature and density in streamer discharge plasma.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"3 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":"130968499","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}
Jianhao Ma, Shoulong Dong, Hongmei Liu, Liang Yu, C. Yao
{"title":"A High-gain nanosecond pulse generator based on inductor energy storage and pulse forming line voltage superposition","authors":"Jianhao Ma, Shoulong Dong, Hongmei Liu, Liang Yu, C. Yao","doi":"10.1109/PPPS34859.2019.9009869","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009869","url":null,"abstract":"Pulsed gas discharge is an important means of generating low temperature plasma. Short pulses with fast frontier show superior performance in terms of increasing the active particle content, ionization coefficient and electron conversion rate due to its higher voltage rise rate. The common nanosecond pulse generator is based on capacitive energy storage. Compared with the nanosecond pulse generator based on capacitive energy storage, the inductive energy storage has outstanding advantages in energy storage density, miniaturization of the device, and less influence of loop inductance. However, the inductive energy storage also suffers from problems such as limitation of disconnect switch, uncontrollable outputs and waveform distortion. In this paper, the inductance unit in the transmission line is used as the energy storage inductance, and combined with the characteristics of the rectangular pulse output of the transmission line, and the modular voltage superposition is carried out by using the propagation delay of electromagnetic wave in the transmission line to achieve high-gain rectangular nanosecond pulse output. Then we expand the design of the terminal superposition structure, optimize the magnetic field distribution between the lines to reduce the waveform distortion, and output the nanosecond short pulse. Finally, the paper analyzes the load matching characteristics of the designed pulse generator and provides experimental support for the actual application of the generator. In this paper, the superposition experiment of 10-stage inductive energy storage modules was carried out. The experimental results show that the time-delay isolation method of transmission line can effectively isolate the pulse voltage at the front and rear. The volume of the 10-stage circuit module is 25 cm*6 cm*12 cm, rectangular waveform output, the charging voltage is DC 58 V, the voltage amplitude is 8.2 kV, the voltage gain is about 140 times, the pulse duration is 23 ns and the rise time is 8 ns.","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":"131037415","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":"Microsecond Fast, 100 kV Modular Pulse Charger","authors":"T. Klein, A. Neuber, J. Dickens","doi":"10.1109/PPPS34859.2019.9009641","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009641","url":null,"abstract":"A pulse charger module was designed and tested for use in a larger system Each pulse charger module is powered with a 12 V Lithium-ion battery and set to charge a nF sized capacitor up to 100 kV in less than 10 µs. This is achieved by initially charging a µF sized capacitor to 3 kV, then switching a thyristor to discharge this capacitor into a step-up pulse transformer to charge the load capacitor. A PIC 18F26K80 8-bit microcontroller in each pulse charger module will be used to control the module, communicate with other modules and a computer, and monitor voltages. The modules are programmed to automatically detect the total number of modules well as communication delays between each module at startup, allowing for synchronous triggering and induvial identification and control. Each module is kept in a low power mode when not in use, and fiber optic communication is used throughout such that electrical isolation between modules and the master computer is ensured.","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":"131056344","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}
N. Matsumoto, M. Yano, M. Shigeishi, D. Wang, T. Namihira
{"title":"Production of Crushed Sand Using Underwater Pulsed Dsicharge","authors":"N. Matsumoto, M. Yano, M. Shigeishi, D. Wang, T. Namihira","doi":"10.1109/PPPS34859.2019.9009977","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009977","url":null,"abstract":"Concrete consists of coarse aggregates, fine aggregates, and cement pastes. The coarse aggregates can be supplied from either crushed stone from mountains or recycled coarse aggregates from waste concrete. Recently, the fine aggregates can be supplied either from crushed sand which made from crushed stone or recycled fine aggregates from waste concrete. In previous days, the fine aggregate could be collected from river, but now become difficult due to regulations. Therefore, the demand for regenerated fine aggregate and crushed sand is expected to increase. Thus, a new recycling and crushing technique is required, and it is considered that crushing technology using pulsed power can be used as one of them. In this study, the coarse aggregate was crushed by underwater pulsed discharge to produce crushed sand, and the voltage condition with good treatment efficiency was optimized. Oven-dry density and water absorption ration of crushed sand were measured and evaluated as to whether it meets the industrial standards. Also, the particle size distribution and generation amount of fine particles were compared between underwater pulsed discharge method and the conventional jaw crusher method.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"32 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":"122825135","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":"Design and Testing of a Compact 40 KV Capacitor Based on Nanodielectric Composites","authors":"K. O'connor, Robert B. Kutz, M. Miranda, R. Curry","doi":"10.1109/PPPS34859.2019.9009679","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009679","url":null,"abstract":"Compact pulsed power systems are often limited by the size and shape of the capacitors required for high voltage energy storage. Marx banks, pulse forming networks, and other devices requiring multiple capacitors are larger than necessary due to the size and shape of the capacitors as well as the geometry of the connection terminals. The size and weight of the capacitor are determined by the energy density of the capacitor dielectric and the dielectric strength of the surrounding insulation. While doorknob-style capacitors are commonly implemented in these devices, the cylindrical shape does not permit efficient packing of multiple capacitors to fill the available volume. Alternative capacitors, such as those based on mica films, have an improved form factor but have end terminations that add inductance in many assemblies. A new effort is addressing these design issues by building the capacitor with nanodielectric composites. The nanodielectric composites combine high dielectric constant ceramic particles with low dielectric constant, high dielectric strength polymers to produce materials with both high dielectric constant and high dielectric strength [1]. The combination of these two properties enables higher energy densities than possible with conventional ceramics. The composite materials can also be formed or machined into complex shapes, including rectangular, cylindrical, or coaxial form factors, to improve capacitor packing density while maintaining low inductance connections. The present effort is focused on development of 40 kV, 2.5 nF capacitors for compact capacitor banks in a counter-materiel program. In this contribution, the tradeoffs are discussed in the design and simulation of the new capacitors. The first prototypes are described with preliminary test results.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"12 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":"125987090","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":"Packaging and Evaluation of 100 kV Photoconductive Switches","authors":"J. Culpepper, A. Miller, A. Neuber, J. Dickens","doi":"10.1109/PPPS34859.2019.9009753","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009753","url":null,"abstract":"It is desired to integrate a photoconductive semiconductor switch (PCSS) capable of holding off and switching 100 kV into a package with small parasitic inductance such that sub-nanosecond rise time is still achievable at current amplitudes of hundreds of amperes. A GaAs based PCSS is utilized, which makes it necessary to address the filamentary nature of the current, which may lead to a shortening of device lifetime. In order to design a practical package, COMSOL based 2D electric field simulations have been utilized to aid in shaping the field between the PCSS semiconductor, the electrodes, and the high voltage encapsulant. To deal with the unavoidable high field stresses in the small package, the switch is brought to voltage within a few microseconds only, and then closed. Thus, keeping the duration of voltage stress very short, and the risk of self-triggering due to leakage current low.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"13 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":"126471162","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":"The Push-Pull Plasma Power Supply - A Combining Technique for Increased Stability","authors":"P. Krupski, H. Stryczewska, G. Komarzyniec","doi":"10.1109/PPPS34859.2019.9009934","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009934","url":null,"abstract":"During the operation with a double-electrode Non-thermal Plasma (NTP) reactor with a Gliding Arc Discharge (GAD) there are many technical difficulties [1]. The reactor is the resistance energy receiver with a strongly non-linear characteristics. What is more, high voltages above 10 kV are needed for pre-ionisation during the ignition process, while after ignition, the maintaining voltage is several times less. There is also a need to limit the current immediately for keeping non-thermal conditions in the reactor. A plasma reactor used here is briefly described in the Polish patent [2]. In order to meet the requirements of the reactor's supply, there is a strong suggestion to use a Switched- Mode Power Supply (SMPS), the construction of which combines many interesting features that are not commonly encountered. The push-pull topology is not commonly used in such applications. As a standard, it is used in inverters where the low input voltage is processed. The topology requires a primary winding with special symmetry and the alternating current on the secondary side is obtained by switching the primary current between the two halves of the primary coil by delivering current to the centre tap of the primary coil. In this case, the primary current is switched by IGBT transistors. The control can take place both from the microcontroller and the integrated analogue controller, whose advantage is resistance to radiated disturbances. The power supply can successfully achieve power above 1 kW; however, when working with Micro Gliding Arc Plasma Reactor (MGAPR), such power ranges are not required [3]. In addition, the project is seen to have broad scientific perspectives of development. Improvements of ignition properties were obtained using achievements resulting from work on switching overvoltages. The power supply has a power and frequency regulation. Both of them can work in control feedback loops, but here in the experiment they are not used. The features mentioned are exceptional for the power supply and provide a wide range of possibilities in supplying the nonthermal plasma reactors. There are very wide adjustment properties in the range of 13–26 kHz and it has been proven to be exceptionally efficient in fulfilling its purposes.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"48 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":"125914814","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}
M. Jaritz, T. Franz, R. Christen, M. Bucher, M. Schueller, J. Smajic, A. Stoeckli, M. Bader
{"title":"A Comprehensive Design Procedure for High Voltage Pulse Power Transformers","authors":"M. Jaritz, T. Franz, R. Christen, M. Bucher, M. Schueller, J. Smajic, A. Stoeckli, M. Bader","doi":"10.1109/PPPS34859.2019.9009630","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009630","url":null,"abstract":"In this paper, a comprehensive design procedure for high voltage pulse power transformers is presented. The procedure is based on the finite element method (FEM) and contains an electrical model, a magnetical model, a thermal model of the transformer and a procedure for the isolation design. In addition, to avoid overvoltages within the winding, a model for the dynamic voltage distribution is included in the approach, as well. For validation of the models and the design procedure, a prototype has been built. There, the main focus is on evaluating the parasitics, which are crucial for the shape of the output voltage pulse. Further, the isolation design will be proofed by high voltage impulse tests. In the considered application, the required nominal pulse voltage amplitude is 44.2 kV with a pulse power of 4.42 MW, a pulse length of 5 µs and a maximal rise time of 1 µs.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"29 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":"114433628","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}
M. Mallon, M. Kühn-Kauffeldt, J. Marqués, J. Schein
{"title":"Simplified Radiation Model for Atmospheric Plasma","authors":"M. Mallon, M. Kühn-Kauffeldt, J. Marqués, J. Schein","doi":"10.1109/PPPS34859.2019.9009975","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009975","url":null,"abstract":"The use of Stark broadening in plasma diagnostics is a common tool to derive information about electron density and temperature distributions. In contrast, only limited theoretical work is available, which can be used to interpret experimentally acquired spectra. Current ab initio models do not give a sufficient explanation on the driving effect of radiation interaction with the plasma particles especially in gas mixtures, which are of great importance for technical applications. This work seizes the concept of a radiation model, which calculates the net energy emission intensity within a given spectral window for a specific gas mixture. The line profile in this case derives from a quantum physical description of the dominant effect on spectral lines for thermal plasma - Stark broadening. The model is built on a simplified geometry. Here a plasma cylinder is situated between two electrodes. However, it incorporates radiative emission and absorption phenomena of spectral lines depending on the underlying electron density distribution and influencing the same vice versa. The model generates information on the spectrally resolved net emission intensity and calculates the resulting electron density and temperature profile for a given input current and a given distance to a cooling wall. The method proposed has been calculated for pure Argon and Argon-Helium gas mixtures and compared to experimental spectra as well as plasma parameters acquired from Thomson scattering measurements. Furthermore, the impact of laser energy on the temperature distribution is covered.","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":"131114113","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}
H. Nakajima, M. Akemoto, M. Kawamura, T. Natsui, W. Jiang, T. Sugai, A. Tokuchi, Y. Sawamura
{"title":"Present Status of the Chopper-Type Marx Modulator Development at Kek","authors":"H. Nakajima, M. Akemoto, M. Kawamura, T. Natsui, W. Jiang, T. Sugai, A. Tokuchi, Y. Sawamura","doi":"10.1109/PPPS34859.2019.9009767","DOIUrl":"https://doi.org/10.1109/PPPS34859.2019.9009767","url":null,"abstract":"A Chopper-type Marx modulator is being developed to drive a 10 MW L-band multi-beam klystron for the international linear collider at the High Energy Accelerator Research Organization (KEK). Twenty units are connected in series to provide the klystron with a −120 kV, 140 A, 1.65 ms pulse at a repetition rate of 5 pps. This paper describes the present status of the Chopper-type Marx modulator being developed at KEK.","PeriodicalId":103240,"journal":{"name":"2019 IEEE Pulsed Power & Plasma Science (PPPS)","volume":"371 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":"129161916","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}