Luo Cheng, Zhang Yongmin, Lu Yong, Zhang Shaojie, Wang Pengfei, Wang Haodong, Liu Zhi
State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
School of Electrical Engineering Xi'an Jiaotong University, Xi'an, Shaanxi, China.
Rev Sci Instrum. 2024 Aug 1;95(8). doi: 10.1063/5.0206865.
The discharge arc of a high-current gas spark switch has a strong mechanical effect on the electrode and adjacent objects. The measurement of this mechanical effect on the electrode plays a very important role in switch design and the theoretical study of spark discharge. However, in traditional stress measurement systems, the spatial electromagnetic interference caused by the discharge and the high electrode voltage affects the measurement accuracy and can even damage the experimental instrument. In this paper, an electrode impact stress measurement system based on PVDF piezoelectric film is designed to measure the electrode stress under a strong spatial electromagnetic field and high voltage. The experimental results show that the system can measure the impact pressure of high-voltage and high-current gas spark switch electrodes. The starting time of the stress measurement waveform shows that the shock to the electrode is formed in the initial stage of current buildup. The measured results clearly show the high magnetic field force component in the electrode impact pressure waveform. The shock waveforms induced by different pulse capacitor values, breakdown voltages, and loads are examined. It is found that the shock stress waveforms applied to the electrodes are affected by the peak value of the current, dI/dt, and the discharge duration.
高电流气体火花开关的放电电弧对电极及相邻物体具有很强的机械作用。测量这种对电极的机械作用在开关设计和火花放电的理论研究中起着非常重要的作用。然而,在传统的应力测量系统中,放电产生的空间电磁干扰以及高电极电压会影响测量精度,甚至可能损坏实验仪器。本文设计了一种基于聚偏二氟乙烯(PVDF)压电薄膜的电极冲击应力测量系统,用于测量强空间电磁场和高电压下的电极应力。实验结果表明,该系统能够测量高压高电流气体火花开关电极的冲击压力。应力测量波形的起始时间表明,在电流上升的初始阶段就对电极形成了冲击。测量结果清楚地显示了电极冲击压力波形中的高磁场力分量。研究了不同脉冲电容值、击穿电压和负载所引起的冲击波形。结果发现,施加在电极上的冲击应力波形受电流峰值、dI/dt和放电持续时间的影响。