电磁脉冲模拟装置用3 MV中储电容器的研制

介绍了一台大型垂直极化有界波模拟装置所用中间储能电容器（简称中储电容器）的设计过程和实验结果。电容器采用基于元件和组件的模块化设计，呈锥台状结构，支撑壳体为真空工艺玻璃钢材料。电容器容值由模拟装置等效的二级脉冲压缩回路决定，取值为1.8 nF。电容器内部绝缘介质为十二烷基苯，外部绝缘介质为45#变压器油，设计耐压3 MV，其绝缘长度主要由元件的体绝缘特性决定。采用三维电磁仿真软件估算中储电容器与中储开关构成回路的电感为659 nH，接近于实测数据623 nH。电容器上脉冲电压的测量通过对电容器电流进行积分来获取，而电流的采集采用封装在SF₆气体中的3个膜电阻并联后所构成测量模块实现。实际运行数据表明，中储电容器容值达到设计值，测量探头标定系数稳定，在工作电压3.1 MV条件下未发生绝缘问题。

Development of a 3 MV transfer capacitor used in an electromagnetic pulse simulator

The design process and experimental results of a transfer capacitor used in a large vertical polarization bounded wave simulator are introduced. The capacitor adopts modular design based on capacitor elements and components, and forms a cone shape. The shell is made of vacuum process glass fiber reinforced plastic material. The capacitance value of capacitor is determined by the equivalent two-stage pulse compression circuit of the simulator, which is calculated to be 1.8 nF. The internal insulation medium of capacitor is dodecyl benzene, while the external insulation environment is 45# transformer oil. The designing working voltage is 3 MV, and the capacitor’s insulation length is mainly determined by the body insulation characteristics of capacitor elements. Three-dimensional electromagnetic simulation is used to estimate the inductance of the circuit composed of capacitor and switch, and the result is close to the measured data 623 nH. The measurement for the pulse voltage of capacitor is achieved by integrating the current of the capacitor, and the acquisition of the current is realized by a measurement module which consists of three oxidation film resistors in parallel and encapsulated in SF₆ gas. The actual operation data show that the designed capacity of the transfer capacitor is achieved and the calibration coefficient of the measuring device is stable and the working voltage can reach up to 3.1 MV.