Modeling Methods for the Main Switch of High Pulsed-Power Facilities Based on Transmission Line Code

Based on the transmission line code （TLCODE）, a circuit model is developed here for analyses of main switches in the high pulsed-power facilities. With the structure of the ZR main switch as an example, a circuit model topology of the switch is proposed, and in particular, calculation methods of the dynamic inductance and resistance of the switching arc are described. Moreover, a set of closed equations used for calculations of various node voltages are theoretically derived and numericMly discretized. Based on these discrete equations and the Matlab program, a simulation procedure is established for analyses of the ZR main switch. Voltages and currents at different key points are obtained, and comparisons are made with those of a PSpice L-C model. The comparison results show that these two models are perfectly in accord with each other with discrepancy less than 0.1%, which verifies the effectiveness of the TLCODE model to a certain extent.     

Simulational Investigation of a High-Efficiency X-Band Magnetically Insulated Line Oscillator

The magnetically insulated line oscillator(MILO) is a gigawatt-class, coaxial crossed-field microwave tube, which is at present a major hotspot in the field of high-power microwaves(HPM) research. In order to improve the power conversion efficiency and eliminate or at least minimize anode plasma formation in the load region and radio frequency(RF) breakdown in the slow wave structure(SWS) section, an X-band MILO is presented and investigated numerically with KARAT code. The design idea is briefly presented and the simulation results are given and discussed. In the simulation, HPM is generated with peak power of 3.4 GW, maximum electric field of about 1 MV/cm, and peak power conversion efficiency of 14.0%, when the voltage is 559.1 kV and the current is 43.2 kA. The microwave frequency is pure and falls in the X-band of 9.0 GHz. The theoretical investigation and the simulation results are given to prove that the anode plasma formation and the RF breakdown can be effectively avoided or at least minimized,respectively.     

电子直线加速器计算机控制系统的研制

电子直线加速器作为射线源可用于工业探伤、工业CT、集装箱检测、辐照等领域。本工作所研制的加速器计算机控制系统采用分布式网络控制 ,分三级进行监测和控制 ,可方便地将探伤工艺、CT设备、辐照等的相关控制纳入控制系统中。系统的前端设备通过网络通讯方式联成控制网络 ,分别对各子系统进行采集、测量、控制、保护 ,用软件代替部分硬件 ,在满足原有功能的基础上实现很多新功能 ,且易于测试、生产、维修和维护升级     

Design of the Transmission Lines for 140 GHz ECRH System on HL-2A

A new 140 GHz/2 MW/3 s electron cyclotron resonance heating （ECRH） system composed of two units is now being constructed on HL-2A. As a part of the system, two trans- mission lines marked No.7 ＆ 8 play the role of carrying microwave power from two gyrotrons to the tokamak port. Based on the oversized circular corrugated waveguide technology, an evacu~ ated transmission system with high power capability and high transmission efficiency is designed. Details are presented for the design of the corrugated waveguide, the layout of the proposed lines and the vacuum pumping system. Then mode conversion losses due to coupling, misalignment, bends and gaps are discussed to serve as a reference for analyzing the transmission efficiency and alignment. Finally, a dual-modes propagation case consisting of the HEll and LPn even modes is discussed.     

HI-13串列加速器AMS交替注入系统研制

介绍ＨＩ－１３串列加速器ＡＭＳ离子交替注入系统的结构及主要部件的设计,给出了部分测量结果。     

基于电偶极子辐射模型的三维成像算法

提出了一种基于电偶极子辐射模型的三维成像算法.在研究后向投影算法原理的基础上,利用散射模型分析了近、远场成像的关系,提出先采用电偶极子辐射模型对采样数据进行近场化处理,再将处理后的数据反向投影到成像区域,获得成像图像.利用FDTD数值仿真实现对目标的三维成像,验证了算法的有效性,分析了耦合对成像效果的影响.