直线变压器驱动源磁芯磁化过程的仿真研究  

Simulation Research on Magnetization Processes of Magnetic Cores in Linear Transformer Driver

作　　者：万臻博 丁卫东[1] 孙凤举[2] WAN Zhenbo;DING Weidong;SUN Fengju(School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Northwest Institute of Nuclear Technology,Xi’an 710024,China)

机构地区：[1]西安交通大学电气工程学院,西安710049 [2]西北核技术研究所,西安710024

出　　处：《高电压技术》2024年第4期1792-1800,共9页High Voltage Engineering

基　　金：国家自然科学基金(51790524,51790521)。

摘　　要：磁芯行为对于异常工况下直线变压器驱动源(linear transformer driver,LTD)的输出特性具有很大的影响,为了预测磁芯剩磁状况,为LTD装置调试和运行提供指导,基于磁芯的测试结果构建了准确的数值模型,并应用于LTD的电路仿真。基于4级串联共用腔体LTD数值仿真研究了开关理想时序放电、开关异常自放电、开关非理想时序触发放电及去磁状况下各级磁芯的磁场强度和磁感应强度变化过程。在±70 kV充电电压下的理想时序放电后,各级磁芯最大剩磁变化量为1.27 T,稳态剩磁约为-0.38 T;在±70 kV充电电压下的单支路开关自放电引起的磁芯最大剩磁变化量为1.88 T,稳态剩磁约0.39 T,多支路开关同时自放电将使磁芯快速饱和;当触发时序系数的绝对值>1时,除最先放电的模块,其余模块磁芯先受到反向励磁,然后再正常磁化;去磁过程中越靠近负载的磁芯越早被去磁,磁场强度随着各级磁芯依次去磁而呈现阶梯式上升。该研究结果能够有效地模拟各种工况下LTD磁芯的磁化过程与剩磁状态,判断当前磁芯剩磁对下一次放电脉冲的影响。Behaviors of magnetic cores have a great influence on the output characteristics of linear transformer driver(LTD)in abnormal conditions.In order to predict the residual magnetization of the cores and guide the commissioning and operation of LTD modules,a precise numerical model for circuit simulation of LTD was constructed by utilizing the test results of magnetic cores.The magnetic field intensity and magnetic induction intensity of magnetic cores at all stages were studied under normal discharge,abnormal prefire,and demagnetization through the numerical simulation of the four-stage shared cavity LTD module.With an ideal±70 kV charging voltage discharge sequence,each level of a magnetic core experiences a maximum remanence variation of 1.27 T with a steady remanence of approximately-0.38 T.The maximum remanence variation of the magnetic core due to single-branch self-discharge is 1.88 T under±70 kV charging voltage,with a steady-state remanence of about 0.39 T.The magnetic core becomes saturated immediately after multi-branch switches prefire.During the demagnetization process,the magnetic core closer to the load demagnetizes earlier,and the magnetic field intensity steps up with the demagnetization of all stages of magnetic core.Results in this paper can effectively simulate the magnetization process and remanent status of the LTD magnetic core in various conditions,and judge the influence of the current remanent magnetic core on the next discharge.

关 键 词：直线变压器驱动源 数值模拟 逆Preisach模型 磁化过程 剩磁 磁饱和 

分 类 号：TM40[电气工程—电器]