中文摘要：

为研究脉冲磁场治疗肿瘤的效果与机理,结合脉冲功率技术和现代电力电子技术,采用固态开关IGBT单管并联作为高压大电流放电开关单元,采用聚焦线圈阵列实现脉冲磁场的空间聚焦,研制了一套输出双指数衰减脉冲波形的脉冲磁场发生器.首先建立了球面型磁场聚焦线圈阵列的几何模型,采用COMSOL Multiphysics有限元仿真软件和遗传算法对线圈阵列的磁场聚焦性能进行了优化,获得了取得最佳聚焦效果的线圈电流组合,并且对其实物进行了研制;然后对发生器电路结构进行设计,重点对并联IGBT单管的触发控制电路、驱动电路和IGBT并联电路进行了设计和研制;最后对发生器的输出脉冲电流和磁场波形以及磁场聚焦线圈的聚焦性能进行了实测.测试结果显示,该脉冲磁场发生器工作稳定可靠,输出磁感应强度幅值、重复频率灵活可调,焦点处脉冲磁场最大幅值为1 mT,上升时间1μs,脉宽3.5 μs;磁场聚焦线圈阵列聚焦效果明显,80％ Bm以上区域所对应的面积S80％约为2.6 × 10^-3 m^2,只占聚焦平面面积的2.07％,该脉冲磁场发生器的研制为后续医学实验奠定了基础.

英文摘要：

In order to study the effects and mechanisms of tumor treatment using pulsed magnetic field （PMF）, this paper develops a PMF generator with a set of outputs of double exponential damped pulsed waveforms through combining pulsed power technology and modern power electronic technology. Insulated gate bipolar transistors （IGBTs） are connected in parallel to act as the discharge switch carrying large impulse current. A focusing coil array is adopted to achieve the spatial focusing of the PMF. Firstly, a geometric model of the spherical magnetic field focusing coil array is established. An optimized set of current amplitude values are achieved by simulation using the finite element simulation software COMSOL Muhiphysics, and genetic algorithm are adopted to optimize the magnetic focusing performance of the coil array. The combination of the coil and current with optimal focusing effect was obtained, and a prototype of the focusing coil array was developed. After that, the circuit structure of the PMF generator was designed through electric circuit analysis using PSpice simulation; the IGBT trigger control circuit, the driving circuit and the IGBT parallel circuit were studied and designed especially, which makes the current sharing evenly in the paralleled IGBTs. Finally, the generator was tested to evaluate the performance of the output impulse current, PMF waveform and the focusing performance of the magnetic field focusing coil. The test results show that the PMF generator operates stably and reliably, the amplitude and repetition rate of the output magnetic induction intensity can be adjusted freely within large adjustment ranges. The maximum amplitude of the PMF at the focus point in focusing plane is about 1 mT, while the rise time and pulse width are 1 μs and 3.5μs, respectively. The PMF is focused successfully within a S80% area of about 2.6 × 10^-3 m^2, which is only 2.07% of the whole focusing plane area. The development of the PMF generator lays a foundation for future tumor treatment experiments