基于双电容器耦合和线性补偿的高稳定度平顶脉冲强磁场调控系统分析与设计  

Analysis and Design of a High-Stability Flat-Top Pulsed Magnetic Field Based on the Coupled Double Capacitor Bank Circuits and the Linear Compensation

作　　者：张绍哲 魏文琦 樊俊显 谢剑峰 韩小涛[1,2] Zhang Shaozhe;Wei Wenqi;Fan Junxian;Xie Jianfeng;Han Xiaotao(Wuhan National High Magnetic Field Center,Huazhong University of Science and Technology,Wuhan 430074 China;State Key Laboratory of Advanced Electromagnetic and Technology School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074 China)

机构地区：[1]华中科技大学国家脉冲强磁场科学中心,武汉430074 [2]强电磁技术全国重点实验室(华中科技大学电气与电子工程学院),武汉430074

出　　处：《电工技术学报》2024年第2期303-312,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金重点项目(U21A20458);国家自然科学基金青年基金项目(52107152);国家自然科学基金-创新群体项目(51821005);国家重点研发计划项目(2021YFA1600301)资助。

摘　　要：平顶脉冲磁场具备脉冲磁场强度高和稳态磁场稳定度高的双重优势,是现代物理科学研究的重要工具。为满足脉冲场核磁共振、I-V测量等科学实验对平顶脉冲磁场高稳定度的需求,该文提出基于双电容器回路耦合放电和线性补偿的平顶磁场调控方案。为此,理论分析双电容器回路耦合放电过程,建立配置主/辅回路电容电压和放电时序的优化方法,基于IGBT有源区的流控特性,设计线性调节补偿回路和前馈反馈相结合的控制器,研制与主磁体解耦的1 T补偿磁体,对双电容器回路耦合放电产生的背景磁场进行高精度调控,最终实现了强度为45.2 T、持续时间为8 ms以及稳定度为0.02%的平顶脉冲磁场,满足相关固态核磁共振等科学实验需求。Due to its high strength and stability,the flat-top pulsed magnetic field(FTPMF)is one of the most significant tools for studying the magnetization effect,magneto resistance effect,and electrical transport.The Wuhan National High Magnetic Field Center(WHMFC)in China has built experimental stations of nuclear magnetic resonance(NMR)and current voltage(I-V)based on FTPMF.It requires FTPMF strength exceeding 40 T,flat-top stability within 0.01%,and a flat-top duration exceeding 5 ms.Until now,only the institute of solid-state physics(ISSP)in Japan has achieved an FTPMF of this level based on a DC pulsed generator.However,constructing a large DC pulsed generator is costly and time-consuming.This paper proposes a high-stability FTPMF scheme to meet the requirements of NMR and I-V measurements,combined with coupled double capacitor bank circuits and linear magnetic field compensation.The coupled double capacitor bank circuits generate FTPMF with stability of about 1%,and the linear compensation circuit precisely adjusts the magnetic field to achieve high stability.Firstly,the circuit topology is expounded,including two capacitor circuits coupled by an air-core transformer,a main magnet,a compensating magnet embedded into the main magnet,and a linear regulating circuit of the compensating magnet.Then,the discharge process of the double capacitors is discussed based on circuit state equations.An optimized method for charging voltage and discharge sequence is proposed to generate the background magnetic field.A field-compensation magnet of 1 T is designed with three windings and two decoupling windings to reduce mutual inductance between the main magnet and the compensation magnet from 100μH to 10μH.A linear power supply is proposed based on the current control characteristics of the IGBT in the active region.The IGBT is connected in series with the compensation magnet.An IGBT driver with current and voltage feedback is designed to control the loop current through the gate voltage of the IGBT in the active region.A corr

关 键 词：平顶脉冲磁场 双电容器耦合 磁场补偿 线性调控 高稳定度 

分 类 号：TM15[电气工程—电工理论与新技术]