摘要
获得更高峰值功率是高功率微波(HPM)技术的首要发展趋势,然而HPM在高峰值功率产生方面出现了脉冲缩短、脉冲功率源与微波源的阻抗匹配矛盾等物理和技术障碍。微波功率合成技术作为一种产生更高功率微波较为乐观、可行的途径,可以在一定程度上避免脉冲缩短物理障碍,但是也存在相位控制及阵元同步激励难以实现的技术问题,而且不能解决阻抗匹配矛盾。本文针对上述问题,提出了利用单脉冲功率源驱动高功率多电子束来产生多束微波,再经过功率合成获得更高功率微波的方案。作为该方案的前期研究,论文对单台加速器驱动双阴极二极管产生的强流同步双电子束进行了理论分析、粒子模拟和实验研究。
论文首先利用PIC软件对无磁场约束的强流双电子束进行了模拟,结果显示:(1)在阴阳极间输入电压为442.6kV时,双电子束流值分别为23.6kA和24.0kA,总电功率约20GW,双束流达到峰值的同步精度小于6ns,理论上可获得同步高功率双电子束;(2)双电子束在单漂移管中传输时,双束间存在空间电势叠加效应和电磁力相互吸引作用。同时,对双电子束在各种磁场控制模式下的双漂移管中的传输特性进行了模拟研究,提出了选择双束控制磁场方式的两点依据,确定采用双阴极分别深入到双漂移管磁场均匀区的双螺线管控制方案。
其次,在粒子模拟的基础上,对所需螺线管进行了理论和工程设计,绕制和测试了两个螺线管,同时设计并搭建了双电子束磁场控制系统。
最后,对单台加速器驱动的双阴极二极管进行了实验研究。
(1)强流双电子束轰击目击靶实验结果表明:在二极管电压为442.8 kV时,束流值总和为48.8 kA;双阴极二极管能够产生高功率双电子束,双束总电功率21GW,与模拟结果一致。
(2)在同步双电子束实验中,利用所设计法拉第筒对双束流参数进行了诊断,实验结果表明:在二极管电压约210 kV时,双束流值分别为4.55 kA和4.37 kA;双阴极二极管能够产生高同步双电子束,双束同步精度在4～6ns之内,与模拟结果符合较好。
(3)磁场引导环形双电子束实验结果显示:空心双阴极在二极管电压约380kV时,双环形束流值分别为5.10kA和4.92 kA;所设计磁场系统能够对环形双电子束进行有效约束,有效约束磁场强度约为0.5T。
To obtain higher output power is an important development trend of the high power microwave. However, high power microwave sources face the physical barrier of pulse shortening and the technical trouble of impedance matching contradiction of pulse power supply. As a quite optimistic and feasible way, microwave power combination can avoid pulse shortening barrier to some extent, but it cannot overcome the impedance matching contradiction or the synchro-control problem for array elements. In the thesis, a scheme is presented as follows. Firstly, multi-beam electrons are synchronally produced by utilizing one accelerator. Then multi-beam microwave is generated by the multi-beam electrons. At last, the higher power microwave is obtained by means of power combination of the multi-beam microwave. As a primary research, the intensive synchronal dual-beam electrons generated by one accelerator was studied.
Firstly, PIC simulation on the dual-cathode diode without confining magnetic field was presented with diode impedance of 10Ωand input voltage of 442.6kV. The results shows that a total beam of 47.6kA, gross power of 20GW, and synchronization precision less than 6ns has been obtained. When dual-beam transmits in a single drift tube, the effects of space electric potential superposition and significant electromagnetic interaction exist between the dual-beam electrons. At the same time, simulation investigation on the transmission characteristics of dual-beam current in dual-drift tube under various control magnetic field modes was presented.
Secondly, according to the above simulation results, a control magnetic field mode by using double confining magnetic field solenoides and letting the dual-cathode go deeply into the drift tube where the magnetic field is more symmetrical was adopted. Then, the control magnetic field system for dual-beam was constructed.
Finally, the experiment research on dual-beam electrons was presented based on the PIC simulation results. The experimental result of dual-beam electrons bombarding the witness target indicates that, at diode voltage of 442.8kV, total beam of 48.8kA, gross power of 21GW were obtained. The parameters of dual-beam currents were measured with the Faraday cups in the synchronization experiment, and synchronization precision of 4～6 ns was obtained. The experimental result is in a good agreement with the simulation one. Moreover, the experiment of dual-magnetic field solenoids controlling annular dual-beam current was presented. When diode voltage was 380 kV, total beam of 10 kA and effective confining magnetic density of 0.5 Tesla was obtained.
引文
[1].丁敦高.紧凑型L波段圆波导TM01-TM11模式转换器研究[D].长沙:国防科学技术大学,2006:1.2.
[2]Robert J.Barker,Edl Schamiloglu.High-Power Microwave Sources and Technologies[M].清华大学出版社,2005.6,第一版.
[3].林竞羽,侯德亭.高功率微波技术发展概述[J].航天电子对抗,2003(4):13-17.
[4].戴大富.高功率微波的发展与现状.真空电子技术,2004(5):18-24.
[5].罗勇,李宏福.高功率微波的需求及发展.真空电子技术,2004(1):4-7.
[6].Price.D,J.S.Levine,J.Benford.Diode Plasma Effects on the Microwave Pulse Length from Relativisitc Magnetrons[J],IEEE Trans.Plasma Sci.1998,(26):348.
[7].Miller,R.B.,C.A.Muehlenweg,K.W.Habinger.etal."Super-Reltron Progress."IEEE Trans.Plasma Sci.1994(22):701.
[8].James Benford,John Swegle(著),吴诗信 莫伯锦(译),刘盛纲(校).High Power Microwave[M].电子科技大学出版社.
[9].Jennifer M.Butler,Charles B.Wharton.Twin traveling-wave tube amplifier driven by a Relativistic Backward-Wave Oscillator[J],IEEE Trans.Plasma Sci.1996(24):884.
[10].Levine,J.,N.Aiello,J.Benford,and B.Harteneck.Design and Operation of a Module of Phase-locked Relativistic Magnetrons[J].J.Appl.Phys.1991(70):2838.
[11].Marder,B.,M.C.Clark,L.Bacon,J.Hoffman,R.Lemke,and P.Coleman.The Split-Cavity Oscillator:A High Power E-Beam Modulator and Microwave Source[J].IEEE Trans.Plasma Sci.1992(20):312.
[12].高桂友,陈昆和.微波功率合成方法[J].无线通信技术,2002,2:45-47.
[13].钟哲夫.阵列馈源偏置抛物面天线合成高功率微波的研究[J].强激光与粒子束,2003.15(5):467-470.
[14].李浩,李家胤等.地基HPM空间功率合成系统初探[A].全国第六届高功率微波学术研讨会论文集[C].太原,2004:533-536.
[15].E.A.Gelvich,L.M.Borisov,Y.V.Zhary.etc.The new generation of high-power multiple-beam klystrons[J],IEEE Trans.Microwabe Theory and Tech.1993(41):27
[16].L.Ives,G.Miram,M.Read,M.Mizuhara.etc.Multiple beam gtms for high power RF applications[J],Proceedings of the 2003 Particle Accelerator Conference.
[17].J.Davis,R.Fulton,D.Sherwood and T.kwan.Enhanced-efficiency,narrow-band gigawatt microwave output of the reditron oscillator[J].IEEE Trans.Plasma Sci.1990(18):611.
[18].W.Jiang,J.Dickens,and M.Kristiansen.Efficiency Enhancement of a Coaxial Virtual Cathode Oscillator[J],IEEE Trans.Plasma Sci.1999(27):1543.
[19].H.Sze,D.Price,and B.Harteneck.Phase Locking of Two Strongly Coupled Vircator[J].J.Appl.Phys.1990,67(5):2278-2282.
[20].M.Blank,B.G.Danly,B.Levush,J.P.Calarne,K.Nguyen,J.Petillo,T.A.Hargreave,R.B.True,A.J.Thesis,G.R.Good.Phy.Plasmas.1999(6):4405.
[21].K.R.Varia.Power combining in a single multiple-diode cavity[J].IEEE,MTTS,Int Microwave Syrup.Dig.1978:344-345.
[22].Y.Ma,C.Sun.1-W millimeter-wave Gunn diode combiner[J].IEEE Trans.MTT,1980,28(12):1460-1463.
[23].汪海洋.高功率微波功率合成技术研究[D].电子科技大学,2003:1-3.
[24].张嘉焱.高功率微波空间功率合成的初步研究[D].长沙:国防科学技术大学,2006:56-57.
[25].R.B.米勒.强流带电粒子束物理学导论[M].北京:原子能出版社,1990,第一版.
[26].王乃彦.强流非箍缩型相对论性电子束的产生及其特性的研究[A].全国高功率粒子束十年文集[C].绵阳,1995.494-504.
[27].彭建昌.强流脉冲电子束二极管等离子体漂移速度的研究[J].强激光与粒子束,2001,13(5):654-656.
[28].刘锡三.高功率脉冲功率技术[M].北京:国防工业出版社,2005.8,第一版.
[29].Lovelace R V,E.ott Phys fluids,1974,(17):1263.
[30].Jones M.LA-UR-79-3109,1979.
[31].A.Balkcum,E.Wright,H.Bohlen.etal.Design of a Multiple Beam Klystron for TESLA[J].2003 4~(th) IEEE International Conference on Vacuum Electronics,2003,28(30):263-264.
[32].丁耀根.多注速调管双间隙耦合腔特性的三维计算[A].中国电子学会真空电子学分会第十一届学术年会论文集[C].青岛,1997.8:122-144.
[33].B.Ch.Djubua.Modern Effective Cathodes[J].Radio Technology,1999(4):55-60.
[34].赵凯华,陈熙谋.电磁学[M].北京:人民教育出版社,1978.
[35].魏群.螺线管磁场分布特征[J].长春工业大学学报,2003,24(3):68-70.
[36].谢祖荣,靳其兵,曾建唐.电容放电脉冲充磁技术中放电回路参数的选择[J].辽宁工程技术大学学报(自然科学版),2002,21(2):187-189.
[37].[苏]П.Л.卡兰塔罗夫,Л.А.采伊特林[著].陈汤铭,刘保安等[译].电感计算手册[M].机械工业出版社,第一版:252-253.
[38].彭涛,辜承林.脉冲强磁场及其发展动态[J].电工技术杂志,2002,(11):2-3.
[39].侯昭武.通电螺线管空间点的磁场[J].广西民族学院学报(自然科学版),2005,11(1):105-108.
[40].李立民.高功率二极管碳纤维阴极的研究[D].长沙:国防科学技术大学,2004:33-51.
[41].夏连胜,王勐,黄子平.等.强流电子二极管中阴极等离子体的膨胀[J].物理学报,2004,53(10):3435-3439.
[42].曾正中.实用脉冲功率技术引论[M].陕西科学技术出版社,2003.9:64.