一种新型Z-Pinch PPT的设计和试验

提出一种基于Z-Pinch原理但无需火花塞而自点火新型微脉冲等离子体推力器（Z-Pinch SI PPT）。为了降低推力器的点火电压以及去掉尺寸减小和轻量化的限制，采用点火和放电一体化的改性聚四氟乙烯为推进剂，两个电极分别为钉状阳极和中心有孔的阴极。相比于传统Z Pinch PPT和平行板脉冲等离子体推力器，该推力器的优点是没有活动部件、火花塞以及为火花塞供电的电源，结构更加简单紧凑。目前研制的该型推力器本体尺寸包络仅有21mm左右，质量为15g。在保持较大推功比优势基础上，点火放电的电压峰值仅为同样自点火的同轴PPT的24%，气体PPT的2.4%。真空舱内多次点火实现累计脉冲1万多次的试验结果表明，该推力器点火电压为480V，推功比为17.83μN/W，平均推力为85.6μN。

Design and experiment of a new Z-Pinch PPT

A new type of pulsed plasma thrusters based on the Z-Pinch principle without igniters was developed. In order to reduce the discharge voltage and size, the discharge chamber consists of a solid inner anode and a hollow cathode with an orifice. The space between the electrodes is occupied by a hollow cylindrical bar of modified polytetrafluoroethylene (PTFE) propellant which can be self ignited. Compared with conventional Z-Pinch PPT and pulsed plasma thrusters in the literature, the advantages of this new PPT lie in no moving parts, igniter and igniter power supply. The envelope size of this PPT is about 21mm and the mass is 15g. Based on the advantage of high thrust to power ratio, the discharge voltage peak of the new PPT is 24% of the coaxial PPT, and 2.4% of the gas fed PPT. Experiment result based on over ten thousand shots shows that this PPT works well, and the ignition voltage is 480V, the thrust to power ratio is 17.83μN/W and thrust is 85.6μN.