2008 14th Symposium on Electromagnetic Launch Technology最新文献

{"title":"Implementation of a Three-Phase Switched Reluctance Generator System for Wind Power Applications","authors":"H. Chen","doi":"10.1109/ELT.2008.104","DOIUrl":"https://doi.org/10.1109/ELT.2008.104","url":null,"abstract":"The paper presents a developed switched reluctance wind power generator system. The block diagram and the elements of the system, such as generator, rotor position detector, excitation power converter and controller are described. The transient phase current analysis and the energy analysis of the switched reluctance generator are evaluated. The rotor position and the peak value of the phase current at three different conditions are given. The closed-loop output power control of the switched reluctance wind power generator system implemented by regulating the turn-on angle of the main switches with fuzzy logic algorithm and fixed turn-off angle of the main switches at a precisely optimized value is presented. There are two input control parameters in the fuzzy logic algorithm, namely the deviation of the average DC output current and the variation of the deviation of the average DC output current. The output control parameter of the fuzzy logic algorithm is the increment of the turn-on angle of the main switches. The photographs of the developed 500 W prototype are also given. The tested results show that the error of the closed-loop output power control is within 2.2%, while the rotor speed range is close to the ratio of 1 to 3 with the low rotor speed 405 r/min.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"299 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122795100","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":"Electrical Insulation Performance Comparisons between Kapton and Teflon Coil Insulation Systems for Pulse Power Applications","authors":"Jiing-Liang Wu, E.S. Ortoli, D. Hackworth","doi":"10.1109/ELT.2008.99","DOIUrl":"https://doi.org/10.1109/ELT.2008.99","url":null,"abstract":"Current pulse power alternator windings operate at high current densities and high electromagnetic field levels. Consequently, the winding insulation systems must be designed to withstand high electrical voltage stress and large mechanical loads. Finite element analysis of pulse alternator windings has indicated that good bonding strengths, inter-laminar tensile strength and inter-laminar shear strength, at winding insulation tape interfaces are required to maintain mechanical integrity. These bonding interfaces include the conductor to barrier tape (Teflon or Kapton), barrier tape to barrier tape, barrier tape to glass armor tape, glass armor tape to glass armor tape layers and glass armor tape to composite support structures. Although bonding strength data from adhesive manufacturers is available for bonding metal to metal, bonding strength data for Teflon/Teflon, Kapton/Kapton, Teflon/woven glass and Kapton/woven glass are practically non-existent. Therefore a testing program was developed to determine the mechanical properties of various combinations of barrier tapes and adhesives that were suitable for the high voltage pulse power application. A survey and an evaluation of adhesive properties and performance were conducted to select the prospective adhesives. A total of 11 adhesives were selected and matched with the two prospective barrier tapes: Kapton and Teflon. To further enhance bonding and adhesion, both sides of the tapes were chemically etched. In addition, an evaluation was performed of Teflon tape samples bonded using tapes which came with adhesive on one side with no etching on the opposite side. Multiple samples of all of the candidate barrier tape/adhesive combinations were manufactured and prepared for testing. Testing was performed per specification of ASTM D897 - 01, Standard Test Method for Tensile Properties of Adhesive Bonds. Three rounds of performance testing were conducted to down-select from the initial list of tape-adhesive combinations to the final one tape/adhesive combination that showed the best performance.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129531977","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":"Analysis and Suppression of Detent Force in Tubular Linear Electromagnetic Launcher for Space Use","authors":"Liyi Li, Chengming Zhang, B. Kou","doi":"10.1109/ELT.2008.17","DOIUrl":"https://doi.org/10.1109/ELT.2008.17","url":null,"abstract":"With the exploitation of the astrospace, platform is playing more and more important roles. Linear electromagnetic launcher offers a lot of merits such as high speed, precision- acceleration control, wide adjustable range of the initial launch velocity and projectile mass, high energy conversion efficiency, etc. So it will be the best choice of space platform launching in the future. The main problem that appears in all linear electromagnetic launchers is the cogging force. This paper deals with the cogging-force characteristics of short primary, long secondary tubular linear permanent magnet synchronous motors (TL-PMSM) for electromagnetic launcher (EML). Using finite element method (FEM) to analysis the magnet field and detent force of TLEML. The result shows that the end effect is the main reason for thrust ripple and the end effect force vary in periodicity of a pole pitch as the length of the primary armature increase. The periodicity of interior PM TLEML (IPM-TLEML) and surface-mounted PM TLEML (SPM-TLEML) are same but SPM-TLEML lags behind IPM-TLEML. For IPM-TLEML, when the side teeth-width/pole pitch is about 0.33-0.5, the cogging force is minimum. For SPM-TLEML, the minimum point is around 0.5. The detent force has nothing to with the size of external diameter. The configuration can only influence the magnitude of detent force, but not the cycle. Accordingly, optimizing the side teeth-width is very effective to reduce detent force while designing.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"187 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134190777","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":"Development of a Capacitive Pulsed Power Supply for High-Current High-Velocity Sliding Electrical Contact Studies","authors":"Shengguo Xia, Junjia He, Lixue Chen, Zheng Xiao, Zijian Wang, Manling Dong, Jun Li, Yingchun Gui, Peizhu Liu, Shizhong Li","doi":"10.1109/ELT.2008.97","DOIUrl":"https://doi.org/10.1109/ELT.2008.97","url":null,"abstract":"A pulsed power supply of a 1.5-MJ capacitor bank has been developed for high-current high-velocity sliding electrical contact studies in railgun launches. The system consists of 8 small modules, each with a capacitance of 15 mF, and one large module with a capacitance of 54 mF. All of nine modules use triggered spark gaps as the main switches. Various shapes of high-current pulse can be formed by controlling the charging voltage and firing time of each module. The small module has been designed for the maximum operating voltage of 5 kV, the peak current of 140 kA, the pulse rise time of 0.9 ms, in which semiconducting diode stack is used as crowbar switch. Since the large module has no crowbar switch and relatively small pulse forming inductance, it can supply high-amplitude oscillating current waveform. The effects of the large module are threefold. First, the large module provides a basic current on which the currents of small modules superimpose to form a nearly constant driving current of armature. Second, the oscillating nature of the current can drastically reduce the muzzle arc current; hence suppression of the muzzle arc can be obtained. Third, the crowbar switch can be removed and therefore the cost of the system can be reduced. The experiments were performed to verify the operation performances of the two kinds of modules, where the modules were discharged simultaneously and/or sequentially. The feasibility of large module on the muzzle arc control is also examined. The results of the experiments show that a total current of 400 kA with a 1.5 ms flat-top time can be obtained and all the modules show good performance during the railgun firing.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134564188","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 Speed Water-Cooled Permanent Magnet Motor for Pulse Alternator-Based Pulse Power Systems","authors":"J. E. King, R. M. Kobuck, J. Repp","doi":"10.1109/ELT.2008.101","DOIUrl":"https://doi.org/10.1109/ELT.2008.101","url":null,"abstract":"Pulse alternator-based pulse power systems for electromagnetic rail guns store the required energy for powering the rail gun as stored mechanical inertial energy in the rotating member. The pulse alternator (PA) converts the stored inertial energy into electrical energy that is supplied to the rail gun terminals. The losses in the system and energy delivered to the rail gun projectile reduce the stored inertial energy of the pulse alternator by reducing the operating speed. Pulse alternators require a charging mechanism to accelerate the rotor of the alternator to the desired speed, providing the mechanical stored energy. This is generally accomplished by a motor attached to the alternator shaft. This paper describes the design, manufacture and initial testing of a high speed, water- cooled permanent-magnet (PM) synchronous motor specially designed to accelerate a high speed pulse alternator. The charging motor has been designed to accelerate the pulse alternator from zero speed to full rated alternator speed and to accelerate the alternator back to rated speed after the pulse discharge. Two PM motors are also used to synchronize two separate paralleled pulse alternators prior to discharge into a rail gun load. The PM motor is directly attached to the PA shaft and designed to minimize the axial footprint of the assembly. The motor is operated in a continuous duty cycle which requires water cooling of the stator assembly and air cooling of the rotor. The PM synchronous motor is powered by a variable-frequency, variable voltage electronic drive and operated in a constant torque mode.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"329 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132987415","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":"Multi-Mission Electromagnetic Launcher","authors":"B.D. Skurdal, R.L. Gaigler","doi":"10.1109/ELT.2008.59","DOIUrl":"https://doi.org/10.1109/ELT.2008.59","url":null,"abstract":"The multi-mission electromagnetic launching system employs induction coilgun technology. The system is composed of a launcher, electromagnetic pulse power supply, control system, support equipment and multiple launch packages. The goal of the system is to extend countermeasure decoy effectiveness and expand electromagnetic launch missions. A series of concept feasibility demonstrations were conducted in 2005 and 2006. Concept feasibility demonstrations for the launcher and pulse power supply were conducted in 2005. Launch package concept feasibility demonstrations for a countermeasure decoy were conducted in 2006. In 2007 and 2008, we developed and tested prototype propulsion coil technology to address tactical application capabilities. Results will be discussed for all series of demonstrations. Lockheed Martin MS2 has performed the system concept feasibility demonstrations and prototype testing with support from Sandia National Laboratories1.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133810764","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":"Power Supply Design for High Voltage Capacitor Discharge Railgun Supply Using Thyristors","authors":"A. Julian, J. Black, W. Maier","doi":"10.1109/ELT.2008.110","DOIUrl":"https://doi.org/10.1109/ELT.2008.110","url":null,"abstract":"The detailed design and analysis of a thyristor based capacitor discharge power supply is important in the development of pulsed power technology to accurately predict the voltage and current stress of each component. Simulation of the switching predicts how the voltage is shared by series thyristors and helps size the thyristor snubber circuits. The peak current in the thyristor is predicted. When parallel capacitor discharge supplies are used to drive a railgun the simulation predicts the shape of the current depending on the initial capacitor voltages, delay time between discharge pulses and circuit parameters. A simplified model of the electromechanical behavior of a railgun is developed in order to predict the electrical stress on a solid state switching power supply. A capacitor discharge power supply design is then presented and the behavior is simulated.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"130 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128715793","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":"Review on the Technology Characteristics and the Military Application of Railgun","authors":"Q. Lv, Zhi-yuan Li, Bin Lei, Qiuxue Yang, Ke-yi Zhao, Hong-jun Xiang","doi":"10.1109/ELT.2008.72","DOIUrl":"https://doi.org/10.1109/ELT.2008.72","url":null,"abstract":"The technology characteristics of the railgun were analyzed and concluded, and the corresponding military application was deduced and reviewed. The pulsed power supplies (PPSs) such as the capacitor bank with pulsed forming network (PFN), the CPA as rotary MFCG, the HPG, and the piston-type MFCG were briefly introduced, and the last one is most suitable for the railgun. The metal armature has higher efficiency than the plasma one. Cooperated with the stripped rails, the metal armature can push the light projectile to a velocity of 4.6 km/s without erosion. The simple two-rail railgun has such intrinsic characteristics as low inductance and low breech voltage, only suitable to accelerate the light bullets with high efficiency, while the multi-turn railgun can launch the little heavier bullets as a result of high inductance gradient. The enhanced magnetic field made by the assistant rails or magnets can help to accelerate the armature further, the balance criterion of the energy distribution between the external magnetic field and the railgun current is necessary to optimize the railgun parameters. In a word, the railgun can accelerate a light projectile to a high speed with a high efficiency. On the ground, the dense air prevents the light projectile flying far. In the sky of the satellite orbit, the bulky, heavy and energy-consuming PPS refuses the railgun to be a convenient weapon. But upon the big aeroplane with an altitude of more than 16 km, the railgun with compact MFCG has such advantages as quick response, long combat range, high intercepting precision, and anti-EM-jamming. The weapon system may be a kind of valid weapons to destroy the enemy's missiles, planes, or satellites.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124301356","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":"Analysis of Distributed Energy Railguns to Suppress Secondary Arc Formation","authors":"R. Karhi, J. Mankowski, M. Kristiansen","doi":"10.1109/ELT.2008.95","DOIUrl":"https://doi.org/10.1109/ELT.2008.95","url":null,"abstract":"An investigation into arc splitting at distributed energy feed locations is presented. Distributed energy scheme experiments conducted at Texas Tech University reveal secondary arc formation by arc splitting at distributed current feeds. At these locations, dynamic magnetic pressure regions are believed to perturb the plasma and lead to its division into two separate current carrying bodies. Continuing research into this hypothesis and viable methods of prevention are discussed. A two stage distributed energy railgun is utilized for this analysis. Diagnostics including armature B-dots and a photodiode array facilitate an understanding of the plasma dynamics in the complex multi-stage railgun environment. The length of the free- running plasma arc allegedly is believed to be a contributing parameter into the arc splitting phenomenon. These luminosity data collected from the photodiodes provides an arc length measurement of the light emitting particles within the plasma body. This length is observed to expand and contract in accordance with the corresponding magnetic pressure present within the railgun bore.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123135850","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":"Progress in the Development of a Solid-Projectile Helical Electromagnetic Launcher for Low and Medium Velocity Applications","authors":"T. Engel, J. Neri, M. Veracka, S. Swanekamp","doi":"10.1109/ELT.2008.64","DOIUrl":"https://doi.org/10.1109/ELT.2008.64","url":null,"abstract":"Helical electromagnetic launchers (HEML's) can operate at significantly lower currents and higher efficiency in comparison to conventional railgun and induction coilgun launchers. The HEML's versatility is due, in part, to its large inductance gradient which is typically 2 to 3 orders of magnitude greater than a conventional railgun and can be tailored to almost any value in that range. The University of Missouri (MU) has focused on the development of a low current, high efficiency launcher for low to medium velocity applications. To this end, MU has demonstrated a 40 mm bore times 750 mm length HEML's to launch ~500 gram projectiles to 150 m/s operating at 12 to 15 kA peak currents, 400 to 800 V peak voltages, and measured efficiencies as high as 32%. While this particular HEML used hollow-projectiles, present research efforts at MU are focused on the development of a solid-projectile HEML. This presentation describes a 40 mm bore times 750 mm length solid projectile HEML. The goal of this research is to demonstrate the solid-projectile HEML concept and to measure its performance, relative to the hollow-projectile HEML. The research investigates both a constant gradient HEML and a variable gradient HEML. The variable gradient HEML is a new launcher geometry that operates at constant voltage and current. Compared to the constant gradient HEML, it represents a constant impedance load to the pulse power supply and can have up to 50% lower current.","PeriodicalId":170049,"journal":{"name":"2008 14th Symposium on Electromagnetic Launch Technology","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132101915","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}