【作者】 蒋成玺；

【导师】 潘垣； 丁洪发；

【作者基本信息】 华中科技大学 ， 电力系统及其自动化， 2013， 博士

【摘要】 强磁场作为一种基础研究的重要极端条件，在凝聚态物理、材料科学等研究领域发挥着不可替代的作用。作为获得高场强磁场有效方法的脉冲强磁场实验装置，在全世界范围内受到广泛关注和大力发展。脉冲强磁场电源为脉冲强磁场实验装置提供能量，并影响磁场的强度、波形和质量，是装置的关键和核心部件。本文根据各类脉冲强磁场电源的特点和优劣，并结合华中科技大学国家脉冲强磁场科学中心（筹）现有条件和规划，选择电容器型电源与脉冲发电机型电源作为脉冲强磁场装置的能量来源，重点研究了这两种脉冲强磁场电源系统的具体设计与实现方案。针对磁体供电要求，以及电容器型电源单模块和多模块并联两种工作状态，分析了电容器型电源主要参数对磁场强度、波形的影响，并提出了12.6MJ/25kV电容器型电源系统的总体设计方案；根据电容器型电源模块可靠性及稳定运行的要求，确定各组成部分的功能及其参数要求，重点设计了脉冲电容器及阻尼电感、放电开关及保护电感、续流二极管及续流电阻、极性转换开关等主要元件的实现方案。在电容器型电源系统研制过程中，对该电源系统的主要元件和整个系统的性能和参数进行了测试和分析，验证了设计方案的可行性，并通过对模块阻抗的测试，建立了精确的电容器型电源模块模型，为后续分析奠定模型基础；针对电容器型电源放电瞬间因线路寄生参数引起的瞬态过电压问题，分析了引起瞬态过电压的具体因素，并设计了相应的阻容吸收支路，实验表明该阻容吸收支路能有效抑制瞬态过电压幅值。在脉冲发电机型电源系统设计方面，分析了现有的100MVA/185MJ脉冲发电机系统和磁体需求，优化了脉冲整流器系统的直流侧参数，提出了135MVA脉冲整流器系统的整体设计方案；根据系统特点提出了由晶闸管开关和机械开关并联组成的Crowbar支路作为直流侧故障保护方案；以规划50T/100ms磁体作为负载，仿真分析了脉冲发电机型电源系统的整体工作情况，验证了该设计方案的可行性。在脉冲发电机型电源系统纹波分析及控制策略研究方面，分析了单线圈和双线圈磁体的供电方式和影响平顶磁场纹波的主要因素，以磁场纹波最小化为目标，提出了交流电压，出口电抗器，线路阻抗等参数的系统配置原则；针对双线圈磁体等效电路，提出了全电流平顶、无电流平顶、半电流平顶三种控制策略，分析了各自的优缺点和适用场合，并通过实验验证了无电流平顶控制策略的有效性；针对阶梯波单线圈磁体，分析了在串联12脉波与串联24脉波整流器两种拓扑电路下，两个整流器触发角不对称运行方式时产生的磁场纹波，并给出了纹波最小要求下的最优触发角分配曲线。更多还原

【Abstract】 The high magnetic field is one of the important and basic research tools in condensedmatter physics, materials science and other research areas. Therefore, the pulsed highmagnetic field facility is vigorously developed worldwide as an effective way to obtainhigh magnetic field. The pulsed power supply is one of the core elements of the highmagnetic field facility. The pulsed magnet is energized by the pulsed power supply, whichdirectly determines the strength, waveform and quality of the high magnetic field.Considering the advantages and disadvantages of various pulsed magnetic field powersupplies, and the present conditions and planning of the Wuhan National High MagneticField Center in Huazhong University of Science and Technology, the pulsed capacitor bankand the pulsed generator are selected as the high magnetic field power supply. This paperstudies the design and realization of these two kinds of pulsed power supply for highmagnetic field.According to the single module and multi-module two operation modes of pulsedcapacitor bank power supply, the relation of the main parameters of pulsed capacitor bankpower supply and the strength, waveform of magnetic field is analyzed, and the overalldesign of the pulsed capacitor bank power supply system is proposed. According to thedesign requirements of the main components of the pulsed capacitor bank power supplymodule, the specific design of the pulsed capacitor with the damping inductor, the dischargeswitch with the protection inductor, crowbar branch is present.The pulsed capacitor bank power supply system testing includes main componentstesting and power supply module testing, wherein the module impedance test builds themore precise model of the pulsed capacitor bank power supply module for subsequentanalysis. The circuit with the parasitic capacitance of the cable is analyzed for the transientovervoltage occurred at the moment of discharge, and a RC snubber circuit branch isdesigned to absorb the transient overvoltage.This paper analyses the demand of pulsed generator system and pulsed magnet, anddetermined the DC parameters of the pulse rectifier system, then the overall design of thepulsed rectifier system is proposed. According to the characteristics of the pulsed rectifiersystem, the crowbar branch consisted of a thyristor crowbar branch and a mechanical switch is designed as the protection of DC fault. At last, the overall design of the pulsedrectifier system is verified through the simulation with the planning pulsed magnet.With the analysis of the monocoil magnet circuit and flat-top magnetic field ripple, thesystem configuration principles about AC voltage, export reactor and line impedance isproposed for the magnetic field ripple minimization. According to the analysis of dual-coilmagnet circuit, three control strategies, full current flat-top, no current flat-top, semi-currentflat-top are proposed. The optimal control strategy and the system configuration, which areput forward for the magnetic field ripple minimization, and verified by experiment.According to the analysis of the magnetic field ripple of two topologies,12-pulse rectifierin series and24-pulse rectifier in series, the optimal firing angle distribution curve, underthe asymmetrical trigger angle mode, is obtained.更多还原