S波段3.3 MW脉冲磁控管的可靠性技术研究

Research on Reliability Technology of 3.3 MW S-Band Pulsed Magnetrons

在S波段3.3 MW脉冲磁控管研制过程中,连续多支磁控管在工作比为1.05‰的条件下工作不足100 h,阳极端盖出现明显的氧化现象,经分析轴向电子轰击端盖产生局部高温是引起磁控管阳极端盖氧化的一个重要原因。本文对阴极发射体端部结构进行改进,仿真分析及实验结果证明了改进后的结构可实现对轴向电子的有效抑制。改进后的磁控管在脉冲电压为47.5 kV、脉冲电流为120 A、脉冲宽度为4.2μs、工作比为1.2‰的条件下,输出脉冲功率大于3.3 MW,磁控管已稳定工作超300 h,阳极端盖无氧化现象发生。实验结果为进一步提升磁控管技术性能及推广应用打下了良好基础。

In the developing process of 3.3 MW S-band pulsed magnetrons,the anode end covers of several magnetrons show obvious oxidation in less than 100 hours under a duty ratio of 1.05‰.It is analyzed that a main reason for the anode end covers oxidation is the local high temperature resulted by axial electron impacting.A novel cathode emitter structure is designed to suppress the axial electrons,the simulation and experiment results show that the improved structure works well.Under the anode pulse voltage of 47.5 kV,anode pulse current of 120 A,pulse width of 4.2μs and duty cycle of 1.2‰,the improved magnetron produces an output pulse power greater than 3.3 MW.Furthermore,it works stably for more than 300 hours without obvious oxidation on the anode end covers.The experimental results lay a good foundation for further improving the technical performance and application of magnetrons.